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Research ArticleDesign and Improvement of Routing Protocol for FieldObservation Instrument Networking Based on LEACH Protocol
Jiuyuan Huo Xingyue Deng and Hamzah Murad Mohammed Al-Neshmi
School of Electronic and Information Engineering Lanzhou Jiaotong University Lanzhou 730070 China
Correspondence should be addressed to Jiuyuan Huo huojyfoxmailcom
Received 3 May 2020 Accepted 13 August 2020 Published 1 September 2020
Academic Editor Jose Luis Domınguez-Garcıa
Copyright copy 2020 Jiuyuan Huo et al is is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited
Field observation instruments in cold and arid areas are deployed with many difficulties caused by the harsh natural en-vironment which leads to the lag of information acquisition ability and severely restricts the geoscience research in these areaserefore it is urgent to study the suitable routing technology of observation instrument networks according to the char-acteristics of cold and arid areas In this paper we have studied and designed an improved routing protocol for the fieldobservation instruments network based on the LEACH protocol (FOI-LEACH) Firstly the FOI-LEACH was proposed tomainly improve the LEACH protocol in three aspects (1) the network nodes are heterogeneous and combined with thecharacteristics of field observation instrument networking e residual energy and the rechargeable energy of nodes are addedin the process of cluster head (CH) election to reduce the risk of premature death of CHs and shortened network life cyclecaused by the selection of nodes with less energy as CH (2) In the process of cluster forming the distance from CH to the basestation (BS) and the residual energy of CH is considered when setting the cluster radius to reasonably plan the cluster size andalleviate the ldquohot spotrdquo problem e nonuniform distribution of clusters in the network is enhanced to balance the totalnetwork energy consumption (3) e autonomous zone-based multihop routing mechanism is adopted to solve the lowreliability of data transmission caused by the poor quality of intercluster communication links and premature death of nodes inlong-distance transmission en MATLAB was used to compare the network routing protocol model of the observationinstrument from four aspects network life energy consumption rate stability and throughput e results showed that theimproved algorithm FOI-LEACH balances the network energy consumption and alleviates the ldquohot spotrdquo problem to extendthe lifetime of network nodes
1 Introduction
e cold and arid areas in China represent more than two-thirds of the country e ecological environment in cold andarid areas is fragile but contains indispensable resources of thenational economy and has a prominent strategic position [1]Moreover these areas have formed a field monitoring networksystem composed of three-level positioning observation andresearch stations at the national hospital and institute levelssupplemented by other semipositioning observations andcovering themain ecological environment areas in the cold andarid areas of our country rough observation experimentand demonstration the field monitoring network systemprovides an essential scientific basis for scientific research insuch areas It has become an indispensable and irreplaceable
research force and support platform for scientific research inthese areas However the field stations of cold and arid areasare located in the harsh natural environment which leads to thelag of information acquisition ability and severely restricts thegeological research in these areas [2] erefore it is urgent tostudy the suitable routing technology for observation instru-ment networks according to the characteristics of these areas
To establish the field observation instrument networks incold and arid areas and promote full automation and real-time transmission of field observation data we designed aninstrument network node and gateway node [1] e ob-servation instrument network is mostly deployed in a harshenvironment Although the limited energy of nodes is im-proved by an auxiliary power supply of solar cells the harshenvironment leads to the problem of insufficient battery
HindawiJournal of Electrical and Computer EngineeringVolume 2020 Article ID 8059353 19 pageshttpsdoiorg10115520208059353
charging and the demand of uninterrupted data transmis-sion Hence it is necessary to design a networking routingprotocol with energy supply
It is found that there are certain similarities between theinvestigation and analysis of the field observation envi-ronment in cold and arid areas on the one hand and thecomparative analysis of wireless sensor network (WSN) [3]with highly integrated knowledge and well-advanced tech-nology on the other hand which are self-organizing net-work dynamic topology wireless transmission mediumand multihop network erefore according to the char-acteristics of field observation instrument networking andWSN the routing protocol is improved and optimized
In WSNs the Low Energy Adaptive Clustering Hier-archy (LEACH) [4] designed by Heinzehnan et al ofMassachusetts Institute of Technology in the USA is aclassical and effective energy routing protocol based onclustering As shown in Figure 1 the LEACH protocolbelongs to the hierarchical routing protocols [5] whichclusters nodes in the network and reduces the amount ofsent information by using data fusion technology esensor node does not need to maintain the routing table withcomprehensive information which can effectively improvethe energy utilization of nodes and extend the averageworking time of the network At the same time the hier-archical structure improves the scalability of the WSN
Networks are usually deployed in open unattended en-vironments which make them more vulnerable to attackserefore it is crucial to devise security solutions to thesenetworks But LEACH is more robust against insider attacksthan most other routing protocols [6] In contrast to moreconventional multihop schemes where nodes around the BSare especially attractive for compromise (because they con-centrate all network-to-BS communication flows) CHs inLEACH communicate directly with the BS can be anywherein the network and change from round to round All thesecharacteristics make it harder for an adversary to identify andcompromise strategically more important nodes [7]
However the LEACH algorithm still faces many chal-lenges For example without considering the residual energyof nodes and the distance to the base station (BS) therandomness of cluster head election may cause the far awayfrom the BS cluster head to die quickly due to excessive long-distance communication energy consumption which affectsthe survival time of the whole network In order to solvethese problems in the LEACH protocol FOI-LEACH animproved algorithm for network energy balance was pro-posed considering the energy supply e algorithm wasmainly improved from the following three aspects
(1) e network nodes are heterogeneous and combinedwith the characteristics of field observation instru-ment networking e residual energy and the re-chargeable energy of nodes are added in the processof CH election to reduce the risk of premature deathof CHs and shortened the network life cycle causedby the selection of nodes with less energy as CH
(2) In the process of cluster forming the distance fromCH to the BS and the residual energy of CH is
considered when setting the cluster radius to rea-sonably plan the cluster size and alleviate the ldquohotspotrdquo problem e nonuniform distribution ofclusters in the network is enhanced to balance thetotal network energy consumption
(3) e autonomous zone-based multihop routingmechanism [8] is adopted to solve the low reliabilityof data transmission caused by the poor quality ofintercluster communication links and prematuredeath of nodes in long-distance transmission
e paper is organized as follows the related work wasbriefly described and reviewed in Section 2 in Section 3 theproposed FOI-LEACH protocol is described in detail thenetwork model of field observation instruments is estab-lished and analyzed in Section 4 the experiment settingsresults and corresponding analyses were discussed inSection 5 and finally the conclusions are presented inSection 6
2 Related Works
LEACH routing protocol is a WSN routing algorithmdesigned by Heinzehnan et al from MIT in the UnitedStates which is the earliest typical hierarchical routingprotocol [9] LEACH protocol adopts the method of dis-tributed CH election in which some nodes are randomlyselected from the network as CHs and other nodes becomecluster member nodes [10] e CH broadcasts the messagethat it becomes a CH and other nodes select the CHwith thestrongest received signal to join to form a cluster [9] ecluster member node collects data and transmits it to theCH which receives data and transmits it to the BS throughsingle-hop communication e CHs undertake the heavytasks including managing the member nodes of the clustercollecting the data transmitted by the member nodes datafusion and intercluster forwardingerefore to balance theenergy consumption of nodes CHs rotate and the clusterstructure is updated periodically
e basic idea of the LEACH protocol is to divide thenetwork into clusters of equal size e CH rotates peri-odically and each cycle is called a ldquoroundrdquo Each round is
Cluster headCluster memberSink
Figure 1 e hierarchical model of the LEACH protocol
2 Journal of Electrical and Computer Engineering
divided into two stages the establishment stage of the clusterand the stable transmission stage [10]
In the establishment stage of the cluster each nodegenerates a random number from 0 to 1 and the thresholdT(n) is calculated according to equation (1) en therandom number generated by each node is compared withT(n) If the value is less than T(n) the node is selected as theCH
T(n)
p
1 minus plowast (rmod((1p))) n isin G
0 n notin G
⎧⎪⎪⎪⎨
⎪⎪⎪⎩
(1)
where p is the percentage of CH in all nodes r is the numberof current election rounds rmod (1p) is the number ofnodes that have been selected in this round and G is the setof nodes without CHs selected in this round After the end ofeach CH selection round each selected CH broadcasts itsmessage of becoming a CH to other nodes After receivingthe broadcast message other nodes choose to join a clusteraccording to the received signal strength and send theirjoining message to the selected CH [11] Each CH createsand assigns a TDMA schedule between each member nodeafter its member nodes are joined en end the clusterestablishment stage and start the data transmission stage
In the data transmission stage each member node sendsdata to the CH within its allocated period and the CHtransmits data to the BS after data fusion erefore CHsconsume more energy than member nodes LEACH ensuresthat all nodes are equally likely to act as CHs employing cyclecirculation so that the nodes consume energy in a relativelybalanced manner However factors such as residual energyof nodes and distance from the BS are still not considerede randomness of the CH election may lead to the death ofthe CH far away from the BS due to the rapid exhaustion ofenergy which affects the survival time of the whole network
To address these issues the researchers have proposedmany improvements to the LEACH protocol for each stageHowever because of the difficulty high cost and time-consuming problems of deploying nodes in the field theresearchers use MATLAB NS2 OMNeT++ OPNET andother simulation software to simulate the network whichcan provide objective and reliable data for network planningand design shorten the network simulation time and reducethe investment cost In this paper we will use the MATLABsimulation platform to test and evaluate experimentalperformance Heinzelman et al proposed a centralizedLEACH (C-LEACH) to improve the LEACH protocolperformance Instead of sensor nodes themselves the sinkselects CHs in C-LEACH and the algorithm gives betterresults than the LEACH algorithm [12] In the case of CHelection one improvement scheme is to improve thethreshold T(n) For example Sara al-sodairi considered thecurrent residual energy of nodes to reduce the possibilitythat nodes with less energy are selected as CHs [13]However as the network runs for a long time all the sur-viving nodes will have less energy e correspondingthreshold T(n) also becomes smaller that is the probability
of ordinary nodes being selected as CHs becomes smallerand the number of CHs selected in each round decreasessuccessively which leads to unbalanced network energyconsumption and shorter network survival time Lots ofresearchers put forward methods for the cluster headelection by considering more factors In the hybrid energy-efficient distributed (HEED) protocol cluster heads areselected based on the nodesrsquo remaining energy and nodedegree [14] HEED can asymptotically almost surely guar-antee connectivity of clustered networks and simulationresults demonstrated that it is effective in prolonging thenetwork lifetime and supporting scalable data aggregationBinbing Chen considered the current residual energy of thenode and considered the current average energy of thenetwork [15] As the nodersquos current energy value is less thanthe average energy value it cannot be selected as the CHCompared with the original LEACH protocol better qualitynodes can be selected as CHs which can improve networkperformance and prolong the network life cycle to someextent However it does not prevent the CH from con-sumingmore energy due to the heavy load and long-distancecommunication In [16] fuzzy multiple attribute decision-making (MADM) approach is used to select CHs using threecriteria including residual energy number of neighbors andthe distance from the base station of the nodes e sim-ulation results demonstrated that it is more effective inprolonging the network lifetime in homogeneous environ-ments Soro and Heinzelman proposed cluster head electiontechniques for coverage preservation in WSN based on a setof coverage-aware cost metrics that favor nodes deployed indensely populated network areas as better candidates forcluster head nodes active sensor nodes and routers [17]Compared with the traditional energy-based selectionmethods the methods can increase the clustered sensornetwork lifetimeakkar took into account the factors suchas residual energy the mean value and standard deviation ofthe current network energy and the distance from the nodeto the BS [18] e added energy factor and distance factorcan make the network energy change relatively stable andthe nodes close to the BS are more likely to be selected asCHs so the energy consumption of CHs is relatively bal-anced Compared with the original LEACH the protocol hasa longer stable period and enhances the network stabilityHowever due to the randomness of the clusters generated ineach round the maximum and minimum clusters may beformed making the distribution of network energy con-sumption unreasonable and shortening the network lifecycle In [19] Chang et al solved the possibility of minimumclusters and maximum clusters In the clustering stage thenode selects the CH according to the received broadcastsignal strength and adds a parameter based on the clusteringe parameter comprehensively takes into account thedistance between the node to each CH and the energy factorsof the CHe algorithm can optimize the clustering processto reduce the occurrence of extreme cases such as maximumand minimum clusters and form a more reasonable clusterIt makes the distribution of energy consumption morereasonable and prolongs the life cycle of the network Mehraet al proposed the SE-LEACH protocol in [20] which
Journal of Electrical and Computer Engineering 3
considers the node density residual energy distance fromthe BS and power consumption in selecting the CH At thesame time the non-CH selects the CH according to theresidual energy node density the power dissipated by theCH in the process of operation and the distance to the CHis protocol can increase the stable area of WSN balancethe load and ensure that all nodes similarly consume power
Some scholars have also proposed routing protocols forheterogeneous network structures Smaragdakis et al pro-posed a stable heterogeneous election protocol SEP [21] Inthe SEP protocol two kinds of nodes with different initialenergy are proposed which are the normal node with lessinitial energy and the advanced node with more initialenergy e advanced node is more likely to become a CHthan a normal node In general as the initial energy of thenetwork increases the overall lifetime of the network alsoincreases and the instability period decreases Howeverfactors such as energy and distance are not taken into ac-count in the CH election process so that the energy con-sumption of CH is not balanced
In the improved scheme of intercluster communicationHu and Xiao constructed intercluster multihop routing bycombining the idea of node chain in the PEGASIS protocol[22] Finally the node acting as a Leader on the chainundertakes the task of communication with the BS eprotocol reduces the energy consumed by direct commu-nication between multiple CHs and the BS in the LEACHprotocol At the same time the multihop transmissionbetween CHs also enhances the scalability of the network Liet al considered the ldquohot spotrdquo problem in multihop wirelesssensor networks [23]e hot spot problem refers to that theCH closer to the BS needs to bear more relay traffic thanother CHs leading to the premature death of the CH closerto the BS resulting in the exposure of the network area andpartitioning of network us the author divides the nodesinto clusters of different sizes e cluster radius increaseswith the distance between the CH and the BS In this way theCHs close to the BS bear less relay traffic which relativelybalances the network energy consumption and extends thenetwork life Furthermore in [24] the MHT-LEACHmethod proposed by Emad Alnawafa can determine whetherit is possible to transmit their data to BS through inter-mediate nodes according to its location and distance fromBS Compared with the LEACH protocol MHT-LEACHimproves network life stability and throughput enAlnawafa and Marghescu proposed the IMHT-LEACHmethod in [25] to solve the problem that MHT-LEACHrequires a large amount of energy to transfer data to the CHof the inner group IMHT-LEACH can reduce the energycost of data transfer to BS especially in the huge deploymentarea or the large distance from the sensor area to BSCompared with LEACH and MHT-LEACH protocolsIMHT-LEACH protocol can prolong the lifetime improvethe stability period and increase the throughput of thesensor network
ese protocols significantly reduce energy consump-tion in the data transmission phase but consume muchenergy in the process of establishing routing While ensuringhigh efficiency the efforts must be taken to avoid consuming
too much energy in establishing routes erefore we havemade the following contributions
(1) First of all we consider the factors such as energy inthe cluster head election stage and the clusteringstage solve the energy balance and ldquohot spotrdquoproblems and reduce the risk of premature death ofthe network
(2) en the regional autonomous intercluster multi-hop routing mechanism is adopted in the datatransmission phase to solve the problem of prema-ture death of nodes and achieve the purpose ofbalancing network energy consumption
(3) Finally simulation experiments are carried out onthe protocol and the results show that the networklifetime energy consumption rate stability andthroughput have been improved
3 FOI-LEACH Routing Protocol
Compared with WSNs the network of field observationinstruments is connected with data acquisition equipmentby network nodes Data acquisition instruments are gen-erally connected with several or dozens of sensor devices[26] which can observe a large number of observation el-ements It has the characteristics of large data storagecomplex network structure and so on e network hasrelatively few nodes which have strong processing capacityto process data and instructions to complete the commu-nication with the data acquisition equipment and othertasks ere is auxiliary power supply from solar cells fornetworking nodes but because the field observation in-strument networks are usually deployed in a harsh envi-ronment the problem of energy consumption must be fullyconsidered erefore we proposed an improved routingprotocol based on LEACH protocol to meet the needs of thefield observation instrument networking
31 Improvement in CH Election (reshold At the stage ofCH election the random election method of the originalLEACH protocol may let the nodes with less energy beselected as CHs leading to the premature death of net-working nodes To solve the energy consumption problem inthe harsh environment the energy factor of the node wasconsidered and the concept of ldquoself-energyrdquo was introducedto recharge the node With the continuous development andprogress of environmental energy collection technologyresearchers have been able to collect energy in the envi-ronment such as solar light mechanical vibration and heatand apply them to WSN [27] design sensors that can au-tomatically collect environmental energy e sensor nodecan convert the solar energy vibration energy and thermalenergy in the environment into usable electric energy andautomatically recharge energy for itself forming aWSNwiththe characteristics of self-energy [28] In order to achievelong-term observation and data transmission we adoptedthe solar cell power supply in the field observation instru-ment network so that the energy of network nodes can be
4 Journal of Electrical and Computer Engineering
recharged Correspondingly the election threshold of CHs ismodified to reduce the possibility that nodes with lowerenergy are elected as CHs
e threshold formula of node i in round r is shown asfollows
T(i)
popt
1 minus popt times mod r round 1popt1113872 11138731113872 1113873
timesEr(i) + Eh(i r minus 1)
Eo
i isin G
0 i notin G
⎧⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎨
⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎩
(2)
where popt is the optimal probability of a node becoming aCH Eo is the initial energy of the node Er(i) is the residualenergy of the current node and Eh(i r minus 1) is the energyobtained by the current node in the previous round Sincethe energy acquisition environment of each node is notconstant the energy acquisition rate of node i in k units oftime is denoted as αi(k) and the energy acquired by node iin the rminus 1 round [29] is denoted in the following equation
Eh(i r minus 1) 1113944
T(r)
kT(rminus1)
αi(k) (3)
According to the above analysis in the CH election theimproved threshold should consider the total number ofCHs needed by the network and the number of times eachnode has become a CH as well as the initial energy value ofthe node the residual energy value of the node in theprevious round and the supplied energy value of the nodeIn the process of cluster establishment of the r round eachnode firstly needs to count the initial energy value and thecurrent residual energy value and calculate the energy valueobtained in the previous round according to the energyrecharging status If the residual energy and recharge energyof the node are both low the probability of the node be-coming a CH in the r+ 1 round is reduced to avoid its deathdue to excessive energy consumption On the contrary whenthe residual energy and replenishment energy of the nodeare sufficient the probability of the node becoming a CH isincreased
32 Improvement in ClusteringMethod After the election ofthe CH the clustering operation is performed Since theLEACH protocol divides the network into clusters of equalsize the CHs near the BS not only have to bear the energyconsumed by the data transmission within their clusters butalso the forwarding energy brought by the CHs far awayfrom the BS which leads to unbalanced traffic load betweennodes and form a ldquohot spotrdquo problem In order to alleviateand avoid the ldquohot spotrdquo problem an energy-efficient andbalanced network clustering routing protocol for observa-tion instruments in harsh areas is constructed In the routingprotocol clusters of unequal sizes are constructed and thesize of the cluster is proportional to the distance between theCH and the BS In other words the closer it is to the BS the
smaller the cluster is and it consumes less energy in thecommunication within the cluster and more energy in theintercluster communication On the contrary the fartheraway from the BS the larger the cluster is and the more theenergy it consumes is concentrated in the communicationwithin the cluster Moreover since the node has differentenergy levels in the heterogeneous network not only thedistance between the node and the BS but also the currentresidual energy and recharge energy of the node should beconsidered to calculate the competitive radius [30] whichwas shown in the following equation
Rc 1 minus α timesdmax minus d(i BS)
dmax minus dminminus β times 1 minus
Er(i) + Eh(i r minus 1)
Eo
1113888 11138891113890 1113891 times R0c
(4)
in which α and β are the weighted factors of the value in [01] and satisfy the condition that α + β 1R0
c is the maxi-mum competitive radius dmax and dmin are the maximumand minimum values from nodes to BS in the networkd(i BS) is the distance between the current node i and theBS By dividing the network into clusters of different sizesaccording to the distance from the nodes to the BS thecurrent residual energy and the supply energy of the nodesthe CHs near or far away the BS consume approximatelyequal energy so as to achieve the purpose of energy balancein the field instrument network
33 Improvement in Communication Method After theelection of CHs and the formation of clusters the networkenters the stable transmission stage In general the time ofstable transmission is longer than that of cluster formationIn the LEACH protocol data transmission is a single-hoptransmission at is all member nodes send the collecteddata information to the CH of the cluster and the CH sendsit to the BS after data fusion is causes the CH far awayfrom the BS to consumemore energy so that it may die in thetransmission process and fail to transmit data successfullywhich significantly reduces the network efficiency ere-fore a multihop approach to data transmission was con-sidered and the concept of ldquozonerdquo was introduced in thispaper e zone especially refers to the ring bands formed bytaking the BS as the center of the circle and the adjacentcircumferential lines with different lengths as the radius Azone can contain several clusters and a cluster must belongto a specific zone [8] e BS controls the transmissionenergy broadcasts the information of different intensitiesand divides the monitoring area into three-ring zones A Band C as shown in Figure 2 e data communicationmethod adopts the principle of nearest partitioning that isthe CH in zone C selects the CH closest to it in zone B as thenext hop Similarly the CH in zone B selects the nearest CHin zone A as the next hop e CH in zone A communicatesdirectly with the BS According to the characteristics ofpartitioning because cluster nodes in zone A and zone Bneed to bear more energy consumed by data fusion andforwarding only the nodes in zone A and zone B arepowered by solar cells
Journal of Electrical and Computer Engineering 5
34 Analysis of Heterogeneity In this paper in order toprolong the stable stage of the network we adopted the valueof heterogeneity set in literature [21] to set up two kinds ofnodes with different initial energies namely the normalnodes with lower initial energy and the advanced nodes withhigher initial energy Advanced nodes are more likely tobecome CHs and not easy to die than normal nodes which isto balance energy consumption At the same time the totalenergy of the network has changed If the initial energy of thenormal node is Eo the initial energy of the advanced node is(1 + a) middot Eo So the total energy of the network is changed to(1 minus m) middot Eo + m middot (1 + a) middot Eo (1 + a middot m) middot Eo that is thetotal energy of the network has increased by 1 + am timesAccordingly in the CH election the optimal probability ofthe node becoming the CH has also been changed e
weighted probabilities of normal nodes and advanced nodesare shown in the following equations respectively
pnrm popt
1 + α middot m (5)
padv popt
1 + αmtimes(1 + a) (6)
e optimal CH number is kopt n2π
radicmiddot
EfsEmp
1113969middot
md2toBS [30] where kopt represents the optimal cluster
number n is the number of nodes set in the monitoring areaMtimesM and dtoBS represents the distance between the CHand the BS
For normal nodes the modified election threshold isshown in equation (7) Similarly the election threshold foradvanced nodes is shown in equation (8)
T(i)
pnrm
1 minus pnrm times mod r round 1pnrm( 1113857( 1113857times
Er(i) + Eh(i r minus 1)
Eo
i isin G
0 i notin G
⎧⎪⎪⎪⎪⎨
⎪⎪⎪⎪⎩
(7)
T(i)
padv
1 minus padv times mod r round 1padv( 1113857( 1113857times
Er(i) + Eh(i r minus 1)
Eo
i isin G
0 i notin G
⎧⎪⎪⎨
⎪⎪⎩(8)
In the above two threshold equations it can be foundthat the weighted probabilities are different because theadvanced node has more initial energy Due to the energyfactor is taken into account when electing the CH the higherthe energy is the easier it is to become the CH so theadvanced nodes are more likely to become the CHs than thenormal nodes
35 FOI-LEACH Routing Protocol FOI-LEACH protocolintroduces the concepts of ldquoself-energizedrdquo and ldquozonerdquocombined with the characteristics of field instrument net-working In addition the CH election stage and cluster
formation stage are carried out in each zone respectivelye flow of each round of the FOI-LEACH protocol isshown in Figure 3 and the specific operation steps aredescribed as follows
(1) After the deployment of the network nodes eachnode estimates the distance from the BS according tothe signal strength transmitted by the BS judges andidentifies the zone to which it belongs
(2) At the beginning of the CH election the nodegenerates a random number from 0 to 1 counts thecurrent residual energy Er(i) and the previous roundof energy replenishment Eh(i r minus 1) and determines
ABC
Figure 2 Partitioning method in the routing protocol
6 Journal of Electrical and Computer Engineering
whether the node is an advanced node Moreover ifit is an advanced node it calculates the threshold asshown in equation (8) otherwise it calculates thethreshold as shown in equation (7) and then judgeswhether the random number generated by the nodeis lower than the threshold if so announce themessage that it becomes the CH otherwise it be-comes a member node and waits for the schedulingof the CH
(3) After the CH election according to the BS radiomessage all the nodes maximum distance dmax andminimum dmin of network nodes to the BS and thedistance d(i BS) of the current node to the BS arestatistically counted and the current residual energy ofthe node Er(i) and the energy supply of the previousround Eh(i r minus 1) are calculated and then clustercompetition radii are computed e node detects thereceived announcement message and determineswhether the CH exists within the competition radiusof the zone If so a CH is selected according to thecompetition radius to join and form a cluster If thereis no CH within the competitive radius it automat-ically becomes a CH and publishes a notice
(4) After the cluster is formed the CH creates a TDMAschedule and the member nodes in the cluster waitfor the CH to be scheduled
(5) In the data transmission stage cluster member nodescollect data regularly and send the data directly to theCH through the single-hop transmission e CHcompresses and fuses the received data and thensends it to the nearest CH in the next zone until it istransmitted to the BS Loop through steps 1 to 5 untilthe network fails
4 Network Model of FieldObservation Instruments
41 Network Model In this paper we consider the randomdeployment of n nodes in a square monitoring area with asize of MtimesM e assumptions for the networking envi-ronment are as follows
All networking nodes have unique IDs and areheterogeneousAll networking nodes are randomly deployed in themonitoring area and cannot be moved afterdeploymentAll networking nodes know their residual energy andsome nodes can supplement the energyAll networking nodes can determine the distance fromthe information source according to the intensity of thereceived information
Start
Base station broadcastscluster head election
Node i generatesrandom number t (01)
Is it an advancednode
Becomes the ordinary node and waits for the cluster head node
to broadcast information
Yes
Request to join the nearest cluster
Enter the data transfer phasepartition autonomous multihop
mechanism
Waiting for the scheduling of the cluster head
Cluster headselection
The formationof the cluster
Create aschedule
Datatransmission
After a period oftime
NotltT(n)nrm tltT(n)advYes
Becomes the clusterhead nodes and
broadcasts the message
Waiting for theordinary node to
request to join
Create the TDMAschedule table
Yes
No No
The node performsself-energizing
End
Becomes the clusterhead node and
broadcasts the message
Waiting for theordinary node to
request to join
Create the TDMAschedule table
Figure 3 Flow chart of operation in each round of FOI-LEACH protocol
Journal of Electrical and Computer Engineering 7
e BS is located outside the monitoring area it hassufficient energy resources and each node knows thelocation of the BS
42 Energy Model Energy consumption is an importantcriterion to evaluate the performance of a routing protocole network life mainly depends on the energy consumed indata sending and data receiving Meanwhile the energyconsumed by the CH when using the fusion technologyshould be considered and the energy consumption of thenode in the process of calculation and storage should beneglected LEACH protocol uses first-order wireless mode inWSNs so it adopts a simple energy consumptionmodel [12]e model defines that the energy consumed by each l bitdata sent by the wireless circuit is
ETx(l d) ETxminuselec(l d) + ETxminusamp(l d)
lEelec + lEfsd
2 dlt d0
lEelec + lEmpd4 dge d0
⎧⎨
⎩
(9)
When receiving information the energy consumed bythe wireless circuit receiving l bit data is
ERx(l d) ERxminuselec(l d) lEelec (10)
e energy consumed by data fusion is
EGx lEgather (11)
In equations (9)-(10) d represents the distance betweenthe sending node and the receiving node and Eelec representsthe energy consumed for each bit of data sent or received Inequation (9) Efsd
2 is the energy consumed by the free spacemodel for each l bit of data amplification and Empd4 is theenergy consumed by the multipath attenuation model foreach l bit of data amplification Obviously when the distancebetween nodes becomes more extensive the energy con-sumption increases exponentially erefore if you want toreduce the energy consumption of data transmission youmust reduce the distance between nodes e Egather inequation (11) is expressed as the energy consumed by datafusion for each processing of 1 bit the d0 in equation (9) is athreshold which is determined by the equation (12) and isdefined as 87m in this paper
d0
Efs
Emp
1113971
(12)
5 Simulation Experiments and Analysis
51 Experimental Setting In order to analyze the perfor-mance of the FOI-LEACH protocol this paper conductssimulation experiments onMATLAB simulation platform tocompare it with the original LEACH protocol [4] SEPprotocol [21] and PECRP protocol [31] e simulationexperiments were carried out under the monitoring area of100mtimes 100m and the BS is located outside the monitoringarea with the coordinate of (150 50) As shown in Figure 4
the initial node distribution map distinguishes the nodes ineach zone by color in which red represents the nodes in zoneA blue represents the nodes in zone B and the greenrepresents the nodes in zone C And ldquordquo means the normalnode ldquo+rdquo means the advanced node and ldquotimesrdquo means BS
In the self-energy experiment all the surviving nodes inthe network are replenished with energy once every fiverounds until the simulation end e recharge energy isdistributed randomly to all remaining surviving nodes in thenetwork e total energy of the first replenishment is set to035 J In the later replenishment in order to prevent thenodes in the network from dying when there are too fewnodes We set the attenuation factor alpha to 09 that is theenergy replenishment to all the nodes in the network is 09times of the previous timee initial energy and topology ofall the experimental networks were set to the same envi-ronment When all the nodes in the network die the net-work is considered to be invalid Experiments proved thatthe network works best when the parameters are set to thefollowing valuesm is set to 01 a is set to 2 α is set to 03 andβ is set to 07e range of optimal CH number is [1 14] and10 is taken in this paper the probability of optimal CHnumber is popt 0 1 e three-partition system shown inFigure 2 was adopted in the routing protocol e specificparameters of the simulation experiments are listed inTable 1
52 Determination of the Partitioning Scheme e FOI-LEACH protocol proposed in this paper is based on theimprovement of the LEACH protocol In the initial stage ofnode deployment the distance between the node and the BSis obtained according to the signal strength of the BS re-ceived by the node en the monitoring area is partitionedaccording to the distance To determine the optimal parti-tioning scheme in the FOI-LEACH protocol we proposedthe following five schemes for the protocol and tested themin the partitioning experiment
Scheme 1 e monitoring area is divided into twozones A and B and the zone SA of A is equal to thezone SB of B as shown in Figure 5 (partitioning scheme1) e CH in zone B chooses the CH in zone A closest
0 50 100 1500
10
20
30
40
50
60
70
80
90
100
Advanced node
Normal node
BS
Figure 4 Distribution diagram of initial nodes
8 Journal of Electrical and Computer Engineering
to it for forwarding data and the CHs in zone Acommunicates directly with the BSScheme 2 As shown in Figure 5 (partitioning scheme2) the monitoring area is divided into two zones A andB and the SA of zone A is smaller than the area SB ofzone BScheme 3 e monitoring area is divided into threezones A B and C and the area SA of zone A is equalto the area SB of zone B and smaller than the area SC
of zone C as shown in Figure 5 (partitioning scheme3)Scheme 4 e monitoring area is divided into threezones A B and C and the area SA of zone A is smallerthan the area SB of zone B and smaller than the area SC
of zone C as shown in Figure 5 (partitioning scheme 4)Scheme 5 e monitoring area is divided into threezones A B and C and the area SA of zone A is equal tothe area SC of zone C and smaller than the area SB ofzone B as shown in Figure 5 (partitioning scheme 5)
e survival nodes and the average residual energy ineach round of the five partitioning schemes are drawn inFigures 6 and 7 respectively Based on the experimentalanalysis it can be found that Scheme 3 indicated as a redcurve in the figures has a better performance In scheme 3ie SA SB lt SC the first dead node appears in the 587thround which is later than other schemes that is thestability period is more extended than other schemes eaverage residual energy consumption rate of nodes is alsolower than that of other schemes is is because zones Aand B need to bear more forwarding energy so when thesetwo zones are smaller than zone C the network energyconsumption is more balanced erefore we adopted thepartitioning method of scheme 3 to carry out the simu-lation experiments
53 Analysis of Parameters In equation (4) parameters αand β determine the difference in cluster size erefore therelationship between these two parameters and network lifewas observed by taking α from 0 to 1 and β from 1 to 0 eresults of parameters analysis are shown in Figure 8 whichalso proves the rationality of our unequal clusteringmechanism When parameter α increases from 0 to 1 theeffect of the unequal clustering method is noticeableHowever the impact of parameter β on the network shouldalso be considered If the value of α is too large the lifetimeof the system will be shortened It is because too manyclusters will be generated near the BS and each cluster sendspackets to the BS which results in the waste of energyerefore it needs to determine the optimal values forparameters α and β In this experiment we can concludefrom Figure 8 that when α 0 3 and β 0 7 the death timeof the first node is later and the network is more stable
54 Experimental Comparison Analysis is paper mainlyevaluates the performance of the observation instrumentnetwork routing protocol with and without energy supplythrough the following evaluation elements
Network lifetime the network lifetime is measured bythe survival rate of the whole network nodes whichgenerally represents a certain proportion of the energyloss of the network node In this paper we took thedeath time interval from the beginning of the networkto the last surviving node as the lifetime of the networkEnergy consumption rate it usually refers to the av-erage energy consumption of a node sending or re-ceiving a byte of data It is essential to evaluate theperformance of routing algorithmsStability the stability of the field instruments obser-vation network was evaluated from two aspects thetime interval from the beginning of the network to thedeath of the first node and the number of CHsNetwork throughput the indicator to measure theefficiency of the network which is usually judged by thetotal number of packets sent to BS and the total numberof packets sent to CH
541 Experiments without Energy Supply
(1) Network Lifetime Figure 9 shows the number of sur-viving nodes in the network when the network runs for 2100rounds without being self-energized According to thestatistics of the number of rounds of death node in Table 2the network failure of the LEACH protocol occurs at round276 the network of SEP protocol expires at 462 rounds andnetwork failure of the PECRP protocol at round 438However the FOI-LEACH protocol was not expired untilround 2042 which significantly increased the networksurvival time It is because the FOI-LEACH protocol con-siders such factors as energy and distance in stages of CHelection cluster formation and intercluster communication
Table 1 Parameters in the simulation experiments
Parameter ValueTotal number of nodes N 100Network area (m) 100times100Coordinates of BS (m) (150 50)Data packet size L (bit) 4000Initial energy of normal node (J) 01Initial energy of advanced node (J) 03Energy consumption of transmitting circuit ETX (nJbit) 50
Energy consumption of receiving circuit ERX (nJbit) 50Free space model energy Efs (pJbitm
2) 10Multipath attenuation model energy Emp (pJbitm2) 00013Energy consumption of data fusion EDA (nJbit) 5Probability of the optimal number of CHs popt 01Maximum cluster radius in zone A RcA (m) 125Maximum cluster radius in zone B RcB (m) 125Maximum cluster radius in zone C RcC (m) 25Attenuation factor alpha 09M 01A 2α 03β 07
Journal of Electrical and Computer Engineering 9
AB
(a)
AB
(b)
ABC
(c)
ABC
(d)
ABC
(e)
Figure 5 Partitioning scheme (a) Partitioning scheme 1 SaltSb (b) Partitioning scheme 2 SaSb (c) Partitioning scheme 1 SaSbltSc (d)Partitioning scheme 1 SaltSbltSc (e) Partitioning scheme 1 SaScltSb
AeqBAsBAeqBsC
AsBsCAeqCsB
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
Figure 6 Comparison of active nodes in each round
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
002
004
006
008
01
012
Ave
rage
resid
ual e
nerg
y
AeqBAsBAeqBsC
AsBsCAeqCsB
Figure 7 Comparison of average residual energy in each round
10 Journal of Electrical and Computer Engineering
(2) Average Residual Energy and Energy Dissipation RateFigure 10 shows the graph of the average residual energy ofthe network running 2100 rounds without being self-en-ergized Combined with the network average residual en-ergy which is shown in Table 3 it can be drawn that the FOI-LEACH protocol is more slowly energy consumed Besidesit can be seen from Figure 10 that the energy consumption
rate of the improved network is significantly reduced toachieve the purpose of delaying energy consumption andextending network life
(3) Stability e stability of networking was evaluated fromtwo aspects First it can be seen from Figure 9 that the FOI-LEACH protocol significantly extends the death time of the
Self-energized
400
420
440
460
480
500
520
540
Dea
th ti
me o
f the
firs
t nod
e
01 02 03 04 05 06 07 08 09 10α
Figure 8 Impact of parameters α and β on the network lifetime
LEACHSEP
PECRPImproved protocol
400
160060
0
2000
1000
1200
140020
0
1800
21000
800
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
Figure 9 Comparison of live nodes in each round without power supply
Table 2 Statistics number of rounds of dead nodes of the four protocols without power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 135 160 204 276SEP 174 191 226 462PECRP 338 374 412 438FOI-LEACH 481 684 1272 2042
Journal of Electrical and Computer Engineering 11
first node For the LEACH protocol the nodes began to dieat round 135 SEP protocol at round 174 and PECRPprotocol at round 338 Because the energy factor is takeninto account in selecting the CH energy and distance factorsare taken into account in clustering and the adopted zone-based autonomous multihop communication model mini-mizes the Hello control package the nodes die at round 481for the FOI-LEACH protocol As a result the FOI-LEACHprotocol has better performance than other protocols
Figure 11 shows the distribution of the number ofclusters of the four protocols without energy supply simulatedfor 10 rounds of random elections in which Figure 11(a)represents the statistics number of CHs in each zone of theFOI-LEACH protocol and Figure 11(b) represents the sta-tistics number of CHs in the whole network of FOI-LEACHprotocol Figures 11(c)ndash11(e) represent the statistics numberof CHs of LEACH SEP and PECRP protocols respectively Itcan be seen that the number of CHs of FOI-LEACH protocolis more stable than that of LEACH SEP and PECRP BecauseLEACH and SEP randomly select CHs the number of CHsproduced was unstable e FOI-LEACH protocol formsclusters by selecting CHs with a competitive radius and thenumber of CHs is relatively stable
(4) Network (roughput Figure 12 shows that in theLEACH protocol SEP protocol PECRP protocol and ourproposed FOI-LEACH protocol the total number of packets
sent to BS is approximately 900 2580 2980 and 11140respectively Moreover Figure 13 shows that in the LEACHprotocol SEP protocol PECRP protocol and FOI-LEACHprotocol the total number of packages sent to CHs is ap-proximately 7500 21000 38200 and 119000 respectively Itis because the proposed scheme has a high network lifetimethe total number of packets sent to BS and CHs is muchhigher than other protocols
542 Experiments with Energy Supply
(1) Network Lifetime Figure 14 shows the number of sur-viving nodes in the network when the network runs for 2300rounds self-energized According to the statistics of deathnodes in Table 4 we can find that the network lifetime of thefour protocols all has been extended e network failure ofthe LEACH protocol occurred at round 341 the network ofthe SEP protocol expires at round 665 and network failure ofPECRP protocol at round 530 and the FOI-LEACH pro-tocol was not expired until round 2246 which significantlyincreased the network survival time It is demonstrated thatthe improved schemes can work well in both the environ-ments with or without power supply
(2) Average Residual Energy and Energy Dissipation RateFigure 15 shows the graph of the average residual energy ofthe network running 2300 rounds self-energized Combinedwith the network average residual energy which shown inTable 5 it can be drawn that the FOI-LEACH protocol ismore slowly energy consumed Besides it can be seen fromFigure 15 that the energy consumption rate of the improvednetwork is significantly reduced to achieve the purpose ofdelaying energy consumption and extending network life
(3) Stability For the stability of field instruments net-working it can be seen from Figure 14 that the FOI-LEACHprotocol significantly extends the death time of the first
1800
2000
1000
1600
210060
0
200
8000
120040
0
1400
Number of rounds
0
002
004
006
008
01
012
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 10 Comparison of average residual energy in each round without power supply
Table 3 Statistics of the average residual energy (J) of nodes of thefour protocols without power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0075 0007 0 0SEP 0094 002 0 0PECRP 0088 0053 0 0FOI-LEACH 0113 0092 0043 152times10minus5
12 Journal of Electrical and Computer Engineering
ABC
0
1
2
3
4
5
6
7Co
mpa
rison
of C
Hs i
n ea
ch re
gion
2 3 4 5 6 7 8 9 101Number of rounds
(a)
0
2
4
6
8
10
12
14
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(d)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 11 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol without power supply
Journal of Electrical and Computer Engineering 13
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
2000
4000
6000
8000
10000
12000
Pack
ets t
o BS
LEACHSEP
PECRPImproved protocol
Figure 12 Comparison of packets sent to BS from CHs without power supply
times104
200
400
600
800
1000
1200
2000
1800
21000
1400
1600
Number of rounds
0
2
4
6
8
10
12
Pack
ets t
o CH
LEACHSEP
PECRPImproved protocol
Figure 13 Comparison of packets sent to CHs from member nodes without power supply
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
LEACHSEP
PECRPImproved protocol
Figure 14 Comparison of live nodes in each round with power supply
14 Journal of Electrical and Computer Engineering
Table 4 Statistics number of rounds of dead nodes of the four protocols with power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 177 204 232 341SEP 185 210 264 665PECRP 392 430 493 530FOI-LEACH 555 716 1238 2246
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
002
004
006
008
01
012
014
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 15 Comparison of average residual energy in each round with power supply
Table 5 Statistics of the average residual energy (J) of nodes of the four protocols with power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0086 0018 0 0SEP 0105 0036 0001 0PECRP 0099 007 0 0FOI-LEACH 0124 0109 0062 0001
0
1
2
3
4
5
6
7
8
Com
paris
on o
f CH
s in
each
regi
on
2 3 4 5 6 7 8 9 101Number of rounds
ABC
(a)
0
2
4
6
8
10
12
1415
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
Figure 16 Continued
Journal of Electrical and Computer Engineering 15
0
2
4
6
8
10
12
14
16N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14
16
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(d)
0
2
4
6
8
10
12
14
16
18
20
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 16 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol with power supply
0
2000
4000
6000
8000
10000
12000
14000
Pack
ets t
o BS
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 17 Comparison of packets sent to BS from CHs with power supply
16 Journal of Electrical and Computer Engineering
node e supplied energy promotes the extension of thenetwork lifetime and the stability of the networking for thefour protocols in varying degrees For the LEACH protocolthe node began to die at round 177 SEP protocol at round185 PECRP protocol at round 392 and round 555 for theimproved FOI-LEACH protocol
e distributions of the number of clusters in the fourprotocols with energy supply simulated for 10 rounds ofrandom elections are shown in Figure 16 Like the previousfigures Figure 16(a) represents the statistics number of CHsof each zone of FOI-LEACH protocol Figures 16(b)ndash16(e)represent the statistics number of CHs of FOI-LEACHprotocol LEACH protocol SEP protocol and PECRPprotocol respectively Due to the efficient schemes of CHselecting and clustering the FOI-LEACH protocol showssignificantly better performance than the other threeprotocols
(4) Network (roughput In the environment of self-energyas shown in Figure 17 the total number of packets sent toBS of the LEACH protocol SEP protocol PECRP protocoland the proposed FOI-LEACH protocol is approximately2428 3080 3746 and 13265 respectively Moreover inFigure 18 the total number of packages sent to CHs of theLEACH protocol SEP protocol PECRP protocol andFOI-LEACH protocol is approximately 21400 2430044000 and 123200 respectively We can find that the totalnumber of packets sent by our protocol to BS and CHs ismuch higher than the other protocols which also dem-onstrated that the proposed protocol has a better networkthroughout
6 Conclusions
According to the characteristics of field observation in-strument networking an improved protocol FOI-LEACHbased on LEACH protocol was proposed in this paper Byconsidering the energy factor in the CH election threshold
and referring to the SEP protocol to set up two kinds ofnodes with different initial energies which are calledadvanced nodes and normal nodes the network model offield observation instruments has been established Inaddition to solve the problem that the LEACH protocolconsumes much energy during transmission and results inuneven energy consumption for the direct and long-distance transmission the improved protocol adopted the3 zones of partitioning mechanism and the multihoptransmission mechanism to alleviate and avoid the ldquohotspotrdquo problems Furthermore energy supplies were addedto the nodes in A and B zones that are responsible formore energy transmission so as to balance the energyconsumption of the network and prolong the networklifetime In the simulation experiments we compared theperformance of the FOI-LEACH protocol with theLEACH SEP and PECRP protocols in two cases with orwithout energy supply Comparing performance indica-tors of network lifetime energy consumption rate sta-bility and network throughput the proposed FOI-LEACH protocol can slow down the death of nodes andthe energy consumption rate obviously and shows asignificantly better performance than other three proto-cols e experimental results demonstrated that the FOI-LEACH protocol could balance network energy con-sumption and alleviate the ldquohot spotrdquo problem to extendthe lifetime of network nodes in the field observationinstruments network e future work is to implementand port the improved protocol to the hardware of net-working node we designed and developed previously andtest and verify the feasibility and stability of the protocolin the actual situation
Data Availability
e initial nodes are generated randomly in the networkand there are no observation data used in the simulationexperiments
0
20000
40000
60000
80000
100000
120000
140000
Pack
ets t
o CH
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 18 Comparison of packets sent to CHs from nodes with power supply
Journal of Electrical and Computer Engineering 17
Conflicts of Interest
e authors declare that there are no conflicts of interest
Acknowledgments
is work was supported by the National Nature ScienceFoundation of China (Grant no 61862038) the LanzhouTalent Innovation and Entrepreneurship Technology PlanProject (no 2019-RC-14) and the Foundation of a HundredYouth Talents Training Program of Lanzhou JiaotongUniversity
References
[1] J Y Huo Z N Ren and Y R Yang A Kind of InstrumentNetwork Node Equipment and Monitoring System ChinesePatents Beijing China 2017
[2] J Y Huo Key Technology and Application Research ofE-Science Virtual Joint Observation System for Geoscience inCold and Dry Regions University of Chinese Academy ofSciences Beijing China 2012
[3] I F Akyildiz W L Weilian Su Y Sankarasubramaniam andE Cayirci ldquoA survey on sensor networksrdquo IEEE Communi-cations Magazine vol 40 no 8 pp 102ndash114 2002
[4] W R Heinzelman A Chandrakasan and H BalakrishnanldquoEnergy-efficient communication protocol for wirelessmicrosensor networksrdquo in Proceedings of the 33rd HawaiiIntentional Conference on System Sciences Maui HI USAJanuary 2000
[5] D Mehta and S Saxena ldquoA comparative analysis of energyefficient hierarchical routing protocols for wireless sensornetworksrdquo in Proceedings of the 2018 4th InternationalConference on Computing Sciences (ICCS) pp 53ndash58Jalandhar India August 2018
[6] C Karlof and D Wagner ldquoSecure routing in wireless sensornetworks attacks and countermeasuresrdquo Ad Hoc Networksvol 1 2003
[7] L B Oliveira A Ferreira M A Vilaca et al ldquoSecLEACH-onthe security of clustered sensor networksrdquo Signal Processingvol 87 2007
[8] Y Y Gu GW Bai and J J Tao ldquoAZM-LEACH autonomouszone-based multi-hop routing protocol in WSNsrdquo ComputerEngineering and Applications vol 47 no 20 pp 58ndash61 2011
[9] L XWang Research on Routing Technology ofWireless SensorNetworks Based on Data Aggregation Shenyang LigongUniversity Shenyang China 2015
[10] J P Shao Research on Key Energy-Efficient Routing Tech-nology of WSN Based on Cluster Shenyang Ligong UniversityShenyang China 2015
[11] V K Arora V Sharma and M Sachdeva ldquoA survey onLEACH and otherrsquos routing protocols in wireless sensornetworkrdquo Optik vol 127 no 16 pp 6590ndash6600 2016
[12] W B Heinzelman A P Chandrakasan and H BalakrishnanldquoAn application-specific protocol architecture for wirelessmicrosensor networksrdquo IEEE Transactions on WirelessCommunications vol 1 no 4 pp 660ndash670 2002
[13] S Al-Sodairi and R Ouni ldquoReliable and energy-efficientmulti-hop LEACH-based clustering protocol for wirelesssensor networksrdquo Sustainable Computing Informatics andSystems vol 20 pp 1ndash13 2018
[14] O Younis and S Fahmy ldquoHEED a hybrid energy-efficientdistributed clustering approach for ad hoc sensor networksrdquo
IEEE Transactions on Mobile Computing vol 3 no 4pp 366ndash379 2004
[15] B B Chen and Y L Shi ldquoWSN routing protocol based oncluster heads selection in regionsrdquo Computer Engineeringvol 37 no 19 pp 96ndash98 2011
[16] P Azada ldquoCluster head selection in wireless sensor networksunder fuzzy environmentrdquo ISRN Sensor Networks vol 2013Article ID 909086 8 pages 2013
[17] S Soro and W B Heinzelman ldquoCluster head election tech-niques for coverage preservation in wireless sensor networksrdquoAd Hoc Networks vol 7 no 5 pp 955ndash972 2009
[18] A akkar ldquoDEAL distance and energy based advancedleach protocolrdquo in Proceedings of the International Conferenceon Information and Communication Technology for IntelligentSystems pp 370ndash376 Ahmedabad India March 2017
[19] T Y Chang W N Liu Y Zhang and H Y Li ldquoOptimizedLEACH protocol based on distance and energy of clusterheadrdquo Journal of Hebei University (Natural Science Edition)vol 39 no 2 pp 194ndash200 2019
[20] P Mehra M Doja and B Alam ldquoStability enhancement inLEACH (SE-LEACH) for homogeneousWSNrdquo EAI EndorsedTransactions on Scalable Information Systems vol 6 no 20pp 1ndash9 2019
[21] G Smaragdakis I Matta and A Bestavros ldquoSEP a stableelection protocol for clustered heterogeneous wireless sensornetworksrdquo in Proceedings of the Second InternationalWorkshop on Sensor and Actor Network Protocols and Ap-plications (SANPA 2004) pp 1ndash11 Boston MA USA June2004
[22] F S Hu and Q Xiao ldquoMulti-hop routing algorithm of energy-balancing based on LEACHrdquo Journal of Chinese ComputerSystems vol 35 no 1 pp 72ndash75 2014
[23] C F Li M Ye G H Chen and J Wu ldquoAn energy-efficientunequal clustering mechanism for wireless sensor networksrdquoin Proceedings of the IEEE International Conference on MobileAdhoc and Sensor Systems Conference p 604 WashingtonDC USA November 2005
[24] E Alnawafa I Marghescu and MHT ldquoMulti-hop techniquefor the improvement of leach protocolrdquo in Proceedings of the2016 15th RoEduNet Conference Networking in Education andResearch pp 1ndash5 Bucharest Romania September 2016
[25] E Alnawafa and I Marghescu ldquoIMHT improved MHT-LEACH protocol for wireless sensor networksrdquo in Proceedingsof the 2017 8th International Conference on Information andCommunication Systems (ICICS) pp 246ndash251 Irbid JordanApril 2017
[26] J Y Huo Z Zhang and C Tao ldquoUsing IPv6 address ad-vantage to build Network Node of Field observation In-struments in cold and arid areasrdquo China Education Networkno 5 pp 45-46 2018
[27] L Mateu and F Moll ldquoReview of energy harvesting tech-niques and applications for microelectronicsrdquo in Proceedingsof the International Society for Optical Engineering pp 359ndash373 Bellingham WA USA October 2005
[28] G Wang and R Y Wang ldquoRouting algorithm based oncluster-head optimization for self-energized wireless sensornetworkrdquo Journal of Computer Applications vol 38 no 334pp 201ndash216 2018
[29] X P Fan X Yang S Q Liu and Z H Qu ldquoClusteringrouting algorithm for wireless sensor networks with powerharvestingrdquo Computer Engineering vol 39 no 11 pp 126ndash134 2008
18 Journal of Electrical and Computer Engineering
[30] C H Zhang ldquoStudy on the energy heterogeneous clusteringrouting protocol for wireless sensor networksrdquo Science ampTechnology Vision no 13 pp 71+164ndash165 2012
[31] T Liu and F Li ldquoPower-efficient clustering routing protocolbased on applications in wireless sensor networkrdquo in Pro-ceedings of the International Conference on Wireless Com-munications IEEE Press Melbourne Australia September2009
Journal of Electrical and Computer Engineering 19
charging and the demand of uninterrupted data transmis-sion Hence it is necessary to design a networking routingprotocol with energy supply
It is found that there are certain similarities between theinvestigation and analysis of the field observation envi-ronment in cold and arid areas on the one hand and thecomparative analysis of wireless sensor network (WSN) [3]with highly integrated knowledge and well-advanced tech-nology on the other hand which are self-organizing net-work dynamic topology wireless transmission mediumand multihop network erefore according to the char-acteristics of field observation instrument networking andWSN the routing protocol is improved and optimized
In WSNs the Low Energy Adaptive Clustering Hier-archy (LEACH) [4] designed by Heinzehnan et al ofMassachusetts Institute of Technology in the USA is aclassical and effective energy routing protocol based onclustering As shown in Figure 1 the LEACH protocolbelongs to the hierarchical routing protocols [5] whichclusters nodes in the network and reduces the amount ofsent information by using data fusion technology esensor node does not need to maintain the routing table withcomprehensive information which can effectively improvethe energy utilization of nodes and extend the averageworking time of the network At the same time the hier-archical structure improves the scalability of the WSN
Networks are usually deployed in open unattended en-vironments which make them more vulnerable to attackserefore it is crucial to devise security solutions to thesenetworks But LEACH is more robust against insider attacksthan most other routing protocols [6] In contrast to moreconventional multihop schemes where nodes around the BSare especially attractive for compromise (because they con-centrate all network-to-BS communication flows) CHs inLEACH communicate directly with the BS can be anywherein the network and change from round to round All thesecharacteristics make it harder for an adversary to identify andcompromise strategically more important nodes [7]
However the LEACH algorithm still faces many chal-lenges For example without considering the residual energyof nodes and the distance to the base station (BS) therandomness of cluster head election may cause the far awayfrom the BS cluster head to die quickly due to excessive long-distance communication energy consumption which affectsthe survival time of the whole network In order to solvethese problems in the LEACH protocol FOI-LEACH animproved algorithm for network energy balance was pro-posed considering the energy supply e algorithm wasmainly improved from the following three aspects
(1) e network nodes are heterogeneous and combinedwith the characteristics of field observation instru-ment networking e residual energy and the re-chargeable energy of nodes are added in the processof CH election to reduce the risk of premature deathof CHs and shortened the network life cycle causedby the selection of nodes with less energy as CH
(2) In the process of cluster forming the distance fromCH to the BS and the residual energy of CH is
considered when setting the cluster radius to rea-sonably plan the cluster size and alleviate the ldquohotspotrdquo problem e nonuniform distribution ofclusters in the network is enhanced to balance thetotal network energy consumption
(3) e autonomous zone-based multihop routingmechanism [8] is adopted to solve the low reliabilityof data transmission caused by the poor quality ofintercluster communication links and prematuredeath of nodes in long-distance transmission
e paper is organized as follows the related work wasbriefly described and reviewed in Section 2 in Section 3 theproposed FOI-LEACH protocol is described in detail thenetwork model of field observation instruments is estab-lished and analyzed in Section 4 the experiment settingsresults and corresponding analyses were discussed inSection 5 and finally the conclusions are presented inSection 6
2 Related Works
LEACH routing protocol is a WSN routing algorithmdesigned by Heinzehnan et al from MIT in the UnitedStates which is the earliest typical hierarchical routingprotocol [9] LEACH protocol adopts the method of dis-tributed CH election in which some nodes are randomlyselected from the network as CHs and other nodes becomecluster member nodes [10] e CH broadcasts the messagethat it becomes a CH and other nodes select the CHwith thestrongest received signal to join to form a cluster [9] ecluster member node collects data and transmits it to theCH which receives data and transmits it to the BS throughsingle-hop communication e CHs undertake the heavytasks including managing the member nodes of the clustercollecting the data transmitted by the member nodes datafusion and intercluster forwardingerefore to balance theenergy consumption of nodes CHs rotate and the clusterstructure is updated periodically
e basic idea of the LEACH protocol is to divide thenetwork into clusters of equal size e CH rotates peri-odically and each cycle is called a ldquoroundrdquo Each round is
Cluster headCluster memberSink
Figure 1 e hierarchical model of the LEACH protocol
2 Journal of Electrical and Computer Engineering
divided into two stages the establishment stage of the clusterand the stable transmission stage [10]
In the establishment stage of the cluster each nodegenerates a random number from 0 to 1 and the thresholdT(n) is calculated according to equation (1) en therandom number generated by each node is compared withT(n) If the value is less than T(n) the node is selected as theCH
T(n)
p
1 minus plowast (rmod((1p))) n isin G
0 n notin G
⎧⎪⎪⎪⎨
⎪⎪⎪⎩
(1)
where p is the percentage of CH in all nodes r is the numberof current election rounds rmod (1p) is the number ofnodes that have been selected in this round and G is the setof nodes without CHs selected in this round After the end ofeach CH selection round each selected CH broadcasts itsmessage of becoming a CH to other nodes After receivingthe broadcast message other nodes choose to join a clusteraccording to the received signal strength and send theirjoining message to the selected CH [11] Each CH createsand assigns a TDMA schedule between each member nodeafter its member nodes are joined en end the clusterestablishment stage and start the data transmission stage
In the data transmission stage each member node sendsdata to the CH within its allocated period and the CHtransmits data to the BS after data fusion erefore CHsconsume more energy than member nodes LEACH ensuresthat all nodes are equally likely to act as CHs employing cyclecirculation so that the nodes consume energy in a relativelybalanced manner However factors such as residual energyof nodes and distance from the BS are still not considerede randomness of the CH election may lead to the death ofthe CH far away from the BS due to the rapid exhaustion ofenergy which affects the survival time of the whole network
To address these issues the researchers have proposedmany improvements to the LEACH protocol for each stageHowever because of the difficulty high cost and time-consuming problems of deploying nodes in the field theresearchers use MATLAB NS2 OMNeT++ OPNET andother simulation software to simulate the network whichcan provide objective and reliable data for network planningand design shorten the network simulation time and reducethe investment cost In this paper we will use the MATLABsimulation platform to test and evaluate experimentalperformance Heinzelman et al proposed a centralizedLEACH (C-LEACH) to improve the LEACH protocolperformance Instead of sensor nodes themselves the sinkselects CHs in C-LEACH and the algorithm gives betterresults than the LEACH algorithm [12] In the case of CHelection one improvement scheme is to improve thethreshold T(n) For example Sara al-sodairi considered thecurrent residual energy of nodes to reduce the possibilitythat nodes with less energy are selected as CHs [13]However as the network runs for a long time all the sur-viving nodes will have less energy e correspondingthreshold T(n) also becomes smaller that is the probability
of ordinary nodes being selected as CHs becomes smallerand the number of CHs selected in each round decreasessuccessively which leads to unbalanced network energyconsumption and shorter network survival time Lots ofresearchers put forward methods for the cluster headelection by considering more factors In the hybrid energy-efficient distributed (HEED) protocol cluster heads areselected based on the nodesrsquo remaining energy and nodedegree [14] HEED can asymptotically almost surely guar-antee connectivity of clustered networks and simulationresults demonstrated that it is effective in prolonging thenetwork lifetime and supporting scalable data aggregationBinbing Chen considered the current residual energy of thenode and considered the current average energy of thenetwork [15] As the nodersquos current energy value is less thanthe average energy value it cannot be selected as the CHCompared with the original LEACH protocol better qualitynodes can be selected as CHs which can improve networkperformance and prolong the network life cycle to someextent However it does not prevent the CH from con-sumingmore energy due to the heavy load and long-distancecommunication In [16] fuzzy multiple attribute decision-making (MADM) approach is used to select CHs using threecriteria including residual energy number of neighbors andthe distance from the base station of the nodes e sim-ulation results demonstrated that it is more effective inprolonging the network lifetime in homogeneous environ-ments Soro and Heinzelman proposed cluster head electiontechniques for coverage preservation in WSN based on a setof coverage-aware cost metrics that favor nodes deployed indensely populated network areas as better candidates forcluster head nodes active sensor nodes and routers [17]Compared with the traditional energy-based selectionmethods the methods can increase the clustered sensornetwork lifetimeakkar took into account the factors suchas residual energy the mean value and standard deviation ofthe current network energy and the distance from the nodeto the BS [18] e added energy factor and distance factorcan make the network energy change relatively stable andthe nodes close to the BS are more likely to be selected asCHs so the energy consumption of CHs is relatively bal-anced Compared with the original LEACH the protocol hasa longer stable period and enhances the network stabilityHowever due to the randomness of the clusters generated ineach round the maximum and minimum clusters may beformed making the distribution of network energy con-sumption unreasonable and shortening the network lifecycle In [19] Chang et al solved the possibility of minimumclusters and maximum clusters In the clustering stage thenode selects the CH according to the received broadcastsignal strength and adds a parameter based on the clusteringe parameter comprehensively takes into account thedistance between the node to each CH and the energy factorsof the CHe algorithm can optimize the clustering processto reduce the occurrence of extreme cases such as maximumand minimum clusters and form a more reasonable clusterIt makes the distribution of energy consumption morereasonable and prolongs the life cycle of the network Mehraet al proposed the SE-LEACH protocol in [20] which
Journal of Electrical and Computer Engineering 3
considers the node density residual energy distance fromthe BS and power consumption in selecting the CH At thesame time the non-CH selects the CH according to theresidual energy node density the power dissipated by theCH in the process of operation and the distance to the CHis protocol can increase the stable area of WSN balancethe load and ensure that all nodes similarly consume power
Some scholars have also proposed routing protocols forheterogeneous network structures Smaragdakis et al pro-posed a stable heterogeneous election protocol SEP [21] Inthe SEP protocol two kinds of nodes with different initialenergy are proposed which are the normal node with lessinitial energy and the advanced node with more initialenergy e advanced node is more likely to become a CHthan a normal node In general as the initial energy of thenetwork increases the overall lifetime of the network alsoincreases and the instability period decreases Howeverfactors such as energy and distance are not taken into ac-count in the CH election process so that the energy con-sumption of CH is not balanced
In the improved scheme of intercluster communicationHu and Xiao constructed intercluster multihop routing bycombining the idea of node chain in the PEGASIS protocol[22] Finally the node acting as a Leader on the chainundertakes the task of communication with the BS eprotocol reduces the energy consumed by direct commu-nication between multiple CHs and the BS in the LEACHprotocol At the same time the multihop transmissionbetween CHs also enhances the scalability of the network Liet al considered the ldquohot spotrdquo problem in multihop wirelesssensor networks [23]e hot spot problem refers to that theCH closer to the BS needs to bear more relay traffic thanother CHs leading to the premature death of the CH closerto the BS resulting in the exposure of the network area andpartitioning of network us the author divides the nodesinto clusters of different sizes e cluster radius increaseswith the distance between the CH and the BS In this way theCHs close to the BS bear less relay traffic which relativelybalances the network energy consumption and extends thenetwork life Furthermore in [24] the MHT-LEACHmethod proposed by Emad Alnawafa can determine whetherit is possible to transmit their data to BS through inter-mediate nodes according to its location and distance fromBS Compared with the LEACH protocol MHT-LEACHimproves network life stability and throughput enAlnawafa and Marghescu proposed the IMHT-LEACHmethod in [25] to solve the problem that MHT-LEACHrequires a large amount of energy to transfer data to the CHof the inner group IMHT-LEACH can reduce the energycost of data transfer to BS especially in the huge deploymentarea or the large distance from the sensor area to BSCompared with LEACH and MHT-LEACH protocolsIMHT-LEACH protocol can prolong the lifetime improvethe stability period and increase the throughput of thesensor network
ese protocols significantly reduce energy consump-tion in the data transmission phase but consume muchenergy in the process of establishing routing While ensuringhigh efficiency the efforts must be taken to avoid consuming
too much energy in establishing routes erefore we havemade the following contributions
(1) First of all we consider the factors such as energy inthe cluster head election stage and the clusteringstage solve the energy balance and ldquohot spotrdquoproblems and reduce the risk of premature death ofthe network
(2) en the regional autonomous intercluster multi-hop routing mechanism is adopted in the datatransmission phase to solve the problem of prema-ture death of nodes and achieve the purpose ofbalancing network energy consumption
(3) Finally simulation experiments are carried out onthe protocol and the results show that the networklifetime energy consumption rate stability andthroughput have been improved
3 FOI-LEACH Routing Protocol
Compared with WSNs the network of field observationinstruments is connected with data acquisition equipmentby network nodes Data acquisition instruments are gen-erally connected with several or dozens of sensor devices[26] which can observe a large number of observation el-ements It has the characteristics of large data storagecomplex network structure and so on e network hasrelatively few nodes which have strong processing capacityto process data and instructions to complete the commu-nication with the data acquisition equipment and othertasks ere is auxiliary power supply from solar cells fornetworking nodes but because the field observation in-strument networks are usually deployed in a harsh envi-ronment the problem of energy consumption must be fullyconsidered erefore we proposed an improved routingprotocol based on LEACH protocol to meet the needs of thefield observation instrument networking
31 Improvement in CH Election (reshold At the stage ofCH election the random election method of the originalLEACH protocol may let the nodes with less energy beselected as CHs leading to the premature death of net-working nodes To solve the energy consumption problem inthe harsh environment the energy factor of the node wasconsidered and the concept of ldquoself-energyrdquo was introducedto recharge the node With the continuous development andprogress of environmental energy collection technologyresearchers have been able to collect energy in the envi-ronment such as solar light mechanical vibration and heatand apply them to WSN [27] design sensors that can au-tomatically collect environmental energy e sensor nodecan convert the solar energy vibration energy and thermalenergy in the environment into usable electric energy andautomatically recharge energy for itself forming aWSNwiththe characteristics of self-energy [28] In order to achievelong-term observation and data transmission we adoptedthe solar cell power supply in the field observation instru-ment network so that the energy of network nodes can be
4 Journal of Electrical and Computer Engineering
recharged Correspondingly the election threshold of CHs ismodified to reduce the possibility that nodes with lowerenergy are elected as CHs
e threshold formula of node i in round r is shown asfollows
T(i)
popt
1 minus popt times mod r round 1popt1113872 11138731113872 1113873
timesEr(i) + Eh(i r minus 1)
Eo
i isin G
0 i notin G
⎧⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎨
⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎩
(2)
where popt is the optimal probability of a node becoming aCH Eo is the initial energy of the node Er(i) is the residualenergy of the current node and Eh(i r minus 1) is the energyobtained by the current node in the previous round Sincethe energy acquisition environment of each node is notconstant the energy acquisition rate of node i in k units oftime is denoted as αi(k) and the energy acquired by node iin the rminus 1 round [29] is denoted in the following equation
Eh(i r minus 1) 1113944
T(r)
kT(rminus1)
αi(k) (3)
According to the above analysis in the CH election theimproved threshold should consider the total number ofCHs needed by the network and the number of times eachnode has become a CH as well as the initial energy value ofthe node the residual energy value of the node in theprevious round and the supplied energy value of the nodeIn the process of cluster establishment of the r round eachnode firstly needs to count the initial energy value and thecurrent residual energy value and calculate the energy valueobtained in the previous round according to the energyrecharging status If the residual energy and recharge energyof the node are both low the probability of the node be-coming a CH in the r+ 1 round is reduced to avoid its deathdue to excessive energy consumption On the contrary whenthe residual energy and replenishment energy of the nodeare sufficient the probability of the node becoming a CH isincreased
32 Improvement in ClusteringMethod After the election ofthe CH the clustering operation is performed Since theLEACH protocol divides the network into clusters of equalsize the CHs near the BS not only have to bear the energyconsumed by the data transmission within their clusters butalso the forwarding energy brought by the CHs far awayfrom the BS which leads to unbalanced traffic load betweennodes and form a ldquohot spotrdquo problem In order to alleviateand avoid the ldquohot spotrdquo problem an energy-efficient andbalanced network clustering routing protocol for observa-tion instruments in harsh areas is constructed In the routingprotocol clusters of unequal sizes are constructed and thesize of the cluster is proportional to the distance between theCH and the BS In other words the closer it is to the BS the
smaller the cluster is and it consumes less energy in thecommunication within the cluster and more energy in theintercluster communication On the contrary the fartheraway from the BS the larger the cluster is and the more theenergy it consumes is concentrated in the communicationwithin the cluster Moreover since the node has differentenergy levels in the heterogeneous network not only thedistance between the node and the BS but also the currentresidual energy and recharge energy of the node should beconsidered to calculate the competitive radius [30] whichwas shown in the following equation
Rc 1 minus α timesdmax minus d(i BS)
dmax minus dminminus β times 1 minus
Er(i) + Eh(i r minus 1)
Eo
1113888 11138891113890 1113891 times R0c
(4)
in which α and β are the weighted factors of the value in [01] and satisfy the condition that α + β 1R0
c is the maxi-mum competitive radius dmax and dmin are the maximumand minimum values from nodes to BS in the networkd(i BS) is the distance between the current node i and theBS By dividing the network into clusters of different sizesaccording to the distance from the nodes to the BS thecurrent residual energy and the supply energy of the nodesthe CHs near or far away the BS consume approximatelyequal energy so as to achieve the purpose of energy balancein the field instrument network
33 Improvement in Communication Method After theelection of CHs and the formation of clusters the networkenters the stable transmission stage In general the time ofstable transmission is longer than that of cluster formationIn the LEACH protocol data transmission is a single-hoptransmission at is all member nodes send the collecteddata information to the CH of the cluster and the CH sendsit to the BS after data fusion is causes the CH far awayfrom the BS to consumemore energy so that it may die in thetransmission process and fail to transmit data successfullywhich significantly reduces the network efficiency ere-fore a multihop approach to data transmission was con-sidered and the concept of ldquozonerdquo was introduced in thispaper e zone especially refers to the ring bands formed bytaking the BS as the center of the circle and the adjacentcircumferential lines with different lengths as the radius Azone can contain several clusters and a cluster must belongto a specific zone [8] e BS controls the transmissionenergy broadcasts the information of different intensitiesand divides the monitoring area into three-ring zones A Band C as shown in Figure 2 e data communicationmethod adopts the principle of nearest partitioning that isthe CH in zone C selects the CH closest to it in zone B as thenext hop Similarly the CH in zone B selects the nearest CHin zone A as the next hop e CH in zone A communicatesdirectly with the BS According to the characteristics ofpartitioning because cluster nodes in zone A and zone Bneed to bear more energy consumed by data fusion andforwarding only the nodes in zone A and zone B arepowered by solar cells
Journal of Electrical and Computer Engineering 5
34 Analysis of Heterogeneity In this paper in order toprolong the stable stage of the network we adopted the valueof heterogeneity set in literature [21] to set up two kinds ofnodes with different initial energies namely the normalnodes with lower initial energy and the advanced nodes withhigher initial energy Advanced nodes are more likely tobecome CHs and not easy to die than normal nodes which isto balance energy consumption At the same time the totalenergy of the network has changed If the initial energy of thenormal node is Eo the initial energy of the advanced node is(1 + a) middot Eo So the total energy of the network is changed to(1 minus m) middot Eo + m middot (1 + a) middot Eo (1 + a middot m) middot Eo that is thetotal energy of the network has increased by 1 + am timesAccordingly in the CH election the optimal probability ofthe node becoming the CH has also been changed e
weighted probabilities of normal nodes and advanced nodesare shown in the following equations respectively
pnrm popt
1 + α middot m (5)
padv popt
1 + αmtimes(1 + a) (6)
e optimal CH number is kopt n2π
radicmiddot
EfsEmp
1113969middot
md2toBS [30] where kopt represents the optimal cluster
number n is the number of nodes set in the monitoring areaMtimesM and dtoBS represents the distance between the CHand the BS
For normal nodes the modified election threshold isshown in equation (7) Similarly the election threshold foradvanced nodes is shown in equation (8)
T(i)
pnrm
1 minus pnrm times mod r round 1pnrm( 1113857( 1113857times
Er(i) + Eh(i r minus 1)
Eo
i isin G
0 i notin G
⎧⎪⎪⎪⎪⎨
⎪⎪⎪⎪⎩
(7)
T(i)
padv
1 minus padv times mod r round 1padv( 1113857( 1113857times
Er(i) + Eh(i r minus 1)
Eo
i isin G
0 i notin G
⎧⎪⎪⎨
⎪⎪⎩(8)
In the above two threshold equations it can be foundthat the weighted probabilities are different because theadvanced node has more initial energy Due to the energyfactor is taken into account when electing the CH the higherthe energy is the easier it is to become the CH so theadvanced nodes are more likely to become the CHs than thenormal nodes
35 FOI-LEACH Routing Protocol FOI-LEACH protocolintroduces the concepts of ldquoself-energizedrdquo and ldquozonerdquocombined with the characteristics of field instrument net-working In addition the CH election stage and cluster
formation stage are carried out in each zone respectivelye flow of each round of the FOI-LEACH protocol isshown in Figure 3 and the specific operation steps aredescribed as follows
(1) After the deployment of the network nodes eachnode estimates the distance from the BS according tothe signal strength transmitted by the BS judges andidentifies the zone to which it belongs
(2) At the beginning of the CH election the nodegenerates a random number from 0 to 1 counts thecurrent residual energy Er(i) and the previous roundof energy replenishment Eh(i r minus 1) and determines
ABC
Figure 2 Partitioning method in the routing protocol
6 Journal of Electrical and Computer Engineering
whether the node is an advanced node Moreover ifit is an advanced node it calculates the threshold asshown in equation (8) otherwise it calculates thethreshold as shown in equation (7) and then judgeswhether the random number generated by the nodeis lower than the threshold if so announce themessage that it becomes the CH otherwise it be-comes a member node and waits for the schedulingof the CH
(3) After the CH election according to the BS radiomessage all the nodes maximum distance dmax andminimum dmin of network nodes to the BS and thedistance d(i BS) of the current node to the BS arestatistically counted and the current residual energy ofthe node Er(i) and the energy supply of the previousround Eh(i r minus 1) are calculated and then clustercompetition radii are computed e node detects thereceived announcement message and determineswhether the CH exists within the competition radiusof the zone If so a CH is selected according to thecompetition radius to join and form a cluster If thereis no CH within the competitive radius it automat-ically becomes a CH and publishes a notice
(4) After the cluster is formed the CH creates a TDMAschedule and the member nodes in the cluster waitfor the CH to be scheduled
(5) In the data transmission stage cluster member nodescollect data regularly and send the data directly to theCH through the single-hop transmission e CHcompresses and fuses the received data and thensends it to the nearest CH in the next zone until it istransmitted to the BS Loop through steps 1 to 5 untilthe network fails
4 Network Model of FieldObservation Instruments
41 Network Model In this paper we consider the randomdeployment of n nodes in a square monitoring area with asize of MtimesM e assumptions for the networking envi-ronment are as follows
All networking nodes have unique IDs and areheterogeneousAll networking nodes are randomly deployed in themonitoring area and cannot be moved afterdeploymentAll networking nodes know their residual energy andsome nodes can supplement the energyAll networking nodes can determine the distance fromthe information source according to the intensity of thereceived information
Start
Base station broadcastscluster head election
Node i generatesrandom number t (01)
Is it an advancednode
Becomes the ordinary node and waits for the cluster head node
to broadcast information
Yes
Request to join the nearest cluster
Enter the data transfer phasepartition autonomous multihop
mechanism
Waiting for the scheduling of the cluster head
Cluster headselection
The formationof the cluster
Create aschedule
Datatransmission
After a period oftime
NotltT(n)nrm tltT(n)advYes
Becomes the clusterhead nodes and
broadcasts the message
Waiting for theordinary node to
request to join
Create the TDMAschedule table
Yes
No No
The node performsself-energizing
End
Becomes the clusterhead node and
broadcasts the message
Waiting for theordinary node to
request to join
Create the TDMAschedule table
Figure 3 Flow chart of operation in each round of FOI-LEACH protocol
Journal of Electrical and Computer Engineering 7
e BS is located outside the monitoring area it hassufficient energy resources and each node knows thelocation of the BS
42 Energy Model Energy consumption is an importantcriterion to evaluate the performance of a routing protocole network life mainly depends on the energy consumed indata sending and data receiving Meanwhile the energyconsumed by the CH when using the fusion technologyshould be considered and the energy consumption of thenode in the process of calculation and storage should beneglected LEACH protocol uses first-order wireless mode inWSNs so it adopts a simple energy consumptionmodel [12]e model defines that the energy consumed by each l bitdata sent by the wireless circuit is
ETx(l d) ETxminuselec(l d) + ETxminusamp(l d)
lEelec + lEfsd
2 dlt d0
lEelec + lEmpd4 dge d0
⎧⎨
⎩
(9)
When receiving information the energy consumed bythe wireless circuit receiving l bit data is
ERx(l d) ERxminuselec(l d) lEelec (10)
e energy consumed by data fusion is
EGx lEgather (11)
In equations (9)-(10) d represents the distance betweenthe sending node and the receiving node and Eelec representsthe energy consumed for each bit of data sent or received Inequation (9) Efsd
2 is the energy consumed by the free spacemodel for each l bit of data amplification and Empd4 is theenergy consumed by the multipath attenuation model foreach l bit of data amplification Obviously when the distancebetween nodes becomes more extensive the energy con-sumption increases exponentially erefore if you want toreduce the energy consumption of data transmission youmust reduce the distance between nodes e Egather inequation (11) is expressed as the energy consumed by datafusion for each processing of 1 bit the d0 in equation (9) is athreshold which is determined by the equation (12) and isdefined as 87m in this paper
d0
Efs
Emp
1113971
(12)
5 Simulation Experiments and Analysis
51 Experimental Setting In order to analyze the perfor-mance of the FOI-LEACH protocol this paper conductssimulation experiments onMATLAB simulation platform tocompare it with the original LEACH protocol [4] SEPprotocol [21] and PECRP protocol [31] e simulationexperiments were carried out under the monitoring area of100mtimes 100m and the BS is located outside the monitoringarea with the coordinate of (150 50) As shown in Figure 4
the initial node distribution map distinguishes the nodes ineach zone by color in which red represents the nodes in zoneA blue represents the nodes in zone B and the greenrepresents the nodes in zone C And ldquordquo means the normalnode ldquo+rdquo means the advanced node and ldquotimesrdquo means BS
In the self-energy experiment all the surviving nodes inthe network are replenished with energy once every fiverounds until the simulation end e recharge energy isdistributed randomly to all remaining surviving nodes in thenetwork e total energy of the first replenishment is set to035 J In the later replenishment in order to prevent thenodes in the network from dying when there are too fewnodes We set the attenuation factor alpha to 09 that is theenergy replenishment to all the nodes in the network is 09times of the previous timee initial energy and topology ofall the experimental networks were set to the same envi-ronment When all the nodes in the network die the net-work is considered to be invalid Experiments proved thatthe network works best when the parameters are set to thefollowing valuesm is set to 01 a is set to 2 α is set to 03 andβ is set to 07e range of optimal CH number is [1 14] and10 is taken in this paper the probability of optimal CHnumber is popt 0 1 e three-partition system shown inFigure 2 was adopted in the routing protocol e specificparameters of the simulation experiments are listed inTable 1
52 Determination of the Partitioning Scheme e FOI-LEACH protocol proposed in this paper is based on theimprovement of the LEACH protocol In the initial stage ofnode deployment the distance between the node and the BSis obtained according to the signal strength of the BS re-ceived by the node en the monitoring area is partitionedaccording to the distance To determine the optimal parti-tioning scheme in the FOI-LEACH protocol we proposedthe following five schemes for the protocol and tested themin the partitioning experiment
Scheme 1 e monitoring area is divided into twozones A and B and the zone SA of A is equal to thezone SB of B as shown in Figure 5 (partitioning scheme1) e CH in zone B chooses the CH in zone A closest
0 50 100 1500
10
20
30
40
50
60
70
80
90
100
Advanced node
Normal node
BS
Figure 4 Distribution diagram of initial nodes
8 Journal of Electrical and Computer Engineering
to it for forwarding data and the CHs in zone Acommunicates directly with the BSScheme 2 As shown in Figure 5 (partitioning scheme2) the monitoring area is divided into two zones A andB and the SA of zone A is smaller than the area SB ofzone BScheme 3 e monitoring area is divided into threezones A B and C and the area SA of zone A is equalto the area SB of zone B and smaller than the area SC
of zone C as shown in Figure 5 (partitioning scheme3)Scheme 4 e monitoring area is divided into threezones A B and C and the area SA of zone A is smallerthan the area SB of zone B and smaller than the area SC
of zone C as shown in Figure 5 (partitioning scheme 4)Scheme 5 e monitoring area is divided into threezones A B and C and the area SA of zone A is equal tothe area SC of zone C and smaller than the area SB ofzone B as shown in Figure 5 (partitioning scheme 5)
e survival nodes and the average residual energy ineach round of the five partitioning schemes are drawn inFigures 6 and 7 respectively Based on the experimentalanalysis it can be found that Scheme 3 indicated as a redcurve in the figures has a better performance In scheme 3ie SA SB lt SC the first dead node appears in the 587thround which is later than other schemes that is thestability period is more extended than other schemes eaverage residual energy consumption rate of nodes is alsolower than that of other schemes is is because zones Aand B need to bear more forwarding energy so when thesetwo zones are smaller than zone C the network energyconsumption is more balanced erefore we adopted thepartitioning method of scheme 3 to carry out the simu-lation experiments
53 Analysis of Parameters In equation (4) parameters αand β determine the difference in cluster size erefore therelationship between these two parameters and network lifewas observed by taking α from 0 to 1 and β from 1 to 0 eresults of parameters analysis are shown in Figure 8 whichalso proves the rationality of our unequal clusteringmechanism When parameter α increases from 0 to 1 theeffect of the unequal clustering method is noticeableHowever the impact of parameter β on the network shouldalso be considered If the value of α is too large the lifetimeof the system will be shortened It is because too manyclusters will be generated near the BS and each cluster sendspackets to the BS which results in the waste of energyerefore it needs to determine the optimal values forparameters α and β In this experiment we can concludefrom Figure 8 that when α 0 3 and β 0 7 the death timeof the first node is later and the network is more stable
54 Experimental Comparison Analysis is paper mainlyevaluates the performance of the observation instrumentnetwork routing protocol with and without energy supplythrough the following evaluation elements
Network lifetime the network lifetime is measured bythe survival rate of the whole network nodes whichgenerally represents a certain proportion of the energyloss of the network node In this paper we took thedeath time interval from the beginning of the networkto the last surviving node as the lifetime of the networkEnergy consumption rate it usually refers to the av-erage energy consumption of a node sending or re-ceiving a byte of data It is essential to evaluate theperformance of routing algorithmsStability the stability of the field instruments obser-vation network was evaluated from two aspects thetime interval from the beginning of the network to thedeath of the first node and the number of CHsNetwork throughput the indicator to measure theefficiency of the network which is usually judged by thetotal number of packets sent to BS and the total numberof packets sent to CH
541 Experiments without Energy Supply
(1) Network Lifetime Figure 9 shows the number of sur-viving nodes in the network when the network runs for 2100rounds without being self-energized According to thestatistics of the number of rounds of death node in Table 2the network failure of the LEACH protocol occurs at round276 the network of SEP protocol expires at 462 rounds andnetwork failure of the PECRP protocol at round 438However the FOI-LEACH protocol was not expired untilround 2042 which significantly increased the networksurvival time It is because the FOI-LEACH protocol con-siders such factors as energy and distance in stages of CHelection cluster formation and intercluster communication
Table 1 Parameters in the simulation experiments
Parameter ValueTotal number of nodes N 100Network area (m) 100times100Coordinates of BS (m) (150 50)Data packet size L (bit) 4000Initial energy of normal node (J) 01Initial energy of advanced node (J) 03Energy consumption of transmitting circuit ETX (nJbit) 50
Energy consumption of receiving circuit ERX (nJbit) 50Free space model energy Efs (pJbitm
2) 10Multipath attenuation model energy Emp (pJbitm2) 00013Energy consumption of data fusion EDA (nJbit) 5Probability of the optimal number of CHs popt 01Maximum cluster radius in zone A RcA (m) 125Maximum cluster radius in zone B RcB (m) 125Maximum cluster radius in zone C RcC (m) 25Attenuation factor alpha 09M 01A 2α 03β 07
Journal of Electrical and Computer Engineering 9
AB
(a)
AB
(b)
ABC
(c)
ABC
(d)
ABC
(e)
Figure 5 Partitioning scheme (a) Partitioning scheme 1 SaltSb (b) Partitioning scheme 2 SaSb (c) Partitioning scheme 1 SaSbltSc (d)Partitioning scheme 1 SaltSbltSc (e) Partitioning scheme 1 SaScltSb
AeqBAsBAeqBsC
AsBsCAeqCsB
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
Figure 6 Comparison of active nodes in each round
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
002
004
006
008
01
012
Ave
rage
resid
ual e
nerg
y
AeqBAsBAeqBsC
AsBsCAeqCsB
Figure 7 Comparison of average residual energy in each round
10 Journal of Electrical and Computer Engineering
(2) Average Residual Energy and Energy Dissipation RateFigure 10 shows the graph of the average residual energy ofthe network running 2100 rounds without being self-en-ergized Combined with the network average residual en-ergy which is shown in Table 3 it can be drawn that the FOI-LEACH protocol is more slowly energy consumed Besidesit can be seen from Figure 10 that the energy consumption
rate of the improved network is significantly reduced toachieve the purpose of delaying energy consumption andextending network life
(3) Stability e stability of networking was evaluated fromtwo aspects First it can be seen from Figure 9 that the FOI-LEACH protocol significantly extends the death time of the
Self-energized
400
420
440
460
480
500
520
540
Dea
th ti
me o
f the
firs
t nod
e
01 02 03 04 05 06 07 08 09 10α
Figure 8 Impact of parameters α and β on the network lifetime
LEACHSEP
PECRPImproved protocol
400
160060
0
2000
1000
1200
140020
0
1800
21000
800
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
Figure 9 Comparison of live nodes in each round without power supply
Table 2 Statistics number of rounds of dead nodes of the four protocols without power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 135 160 204 276SEP 174 191 226 462PECRP 338 374 412 438FOI-LEACH 481 684 1272 2042
Journal of Electrical and Computer Engineering 11
first node For the LEACH protocol the nodes began to dieat round 135 SEP protocol at round 174 and PECRPprotocol at round 338 Because the energy factor is takeninto account in selecting the CH energy and distance factorsare taken into account in clustering and the adopted zone-based autonomous multihop communication model mini-mizes the Hello control package the nodes die at round 481for the FOI-LEACH protocol As a result the FOI-LEACHprotocol has better performance than other protocols
Figure 11 shows the distribution of the number ofclusters of the four protocols without energy supply simulatedfor 10 rounds of random elections in which Figure 11(a)represents the statistics number of CHs in each zone of theFOI-LEACH protocol and Figure 11(b) represents the sta-tistics number of CHs in the whole network of FOI-LEACHprotocol Figures 11(c)ndash11(e) represent the statistics numberof CHs of LEACH SEP and PECRP protocols respectively Itcan be seen that the number of CHs of FOI-LEACH protocolis more stable than that of LEACH SEP and PECRP BecauseLEACH and SEP randomly select CHs the number of CHsproduced was unstable e FOI-LEACH protocol formsclusters by selecting CHs with a competitive radius and thenumber of CHs is relatively stable
(4) Network (roughput Figure 12 shows that in theLEACH protocol SEP protocol PECRP protocol and ourproposed FOI-LEACH protocol the total number of packets
sent to BS is approximately 900 2580 2980 and 11140respectively Moreover Figure 13 shows that in the LEACHprotocol SEP protocol PECRP protocol and FOI-LEACHprotocol the total number of packages sent to CHs is ap-proximately 7500 21000 38200 and 119000 respectively Itis because the proposed scheme has a high network lifetimethe total number of packets sent to BS and CHs is muchhigher than other protocols
542 Experiments with Energy Supply
(1) Network Lifetime Figure 14 shows the number of sur-viving nodes in the network when the network runs for 2300rounds self-energized According to the statistics of deathnodes in Table 4 we can find that the network lifetime of thefour protocols all has been extended e network failure ofthe LEACH protocol occurred at round 341 the network ofthe SEP protocol expires at round 665 and network failure ofPECRP protocol at round 530 and the FOI-LEACH pro-tocol was not expired until round 2246 which significantlyincreased the network survival time It is demonstrated thatthe improved schemes can work well in both the environ-ments with or without power supply
(2) Average Residual Energy and Energy Dissipation RateFigure 15 shows the graph of the average residual energy ofthe network running 2300 rounds self-energized Combinedwith the network average residual energy which shown inTable 5 it can be drawn that the FOI-LEACH protocol ismore slowly energy consumed Besides it can be seen fromFigure 15 that the energy consumption rate of the improvednetwork is significantly reduced to achieve the purpose ofdelaying energy consumption and extending network life
(3) Stability For the stability of field instruments net-working it can be seen from Figure 14 that the FOI-LEACHprotocol significantly extends the death time of the first
1800
2000
1000
1600
210060
0
200
8000
120040
0
1400
Number of rounds
0
002
004
006
008
01
012
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 10 Comparison of average residual energy in each round without power supply
Table 3 Statistics of the average residual energy (J) of nodes of thefour protocols without power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0075 0007 0 0SEP 0094 002 0 0PECRP 0088 0053 0 0FOI-LEACH 0113 0092 0043 152times10minus5
12 Journal of Electrical and Computer Engineering
ABC
0
1
2
3
4
5
6
7Co
mpa
rison
of C
Hs i
n ea
ch re
gion
2 3 4 5 6 7 8 9 101Number of rounds
(a)
0
2
4
6
8
10
12
14
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(d)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 11 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol without power supply
Journal of Electrical and Computer Engineering 13
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
2000
4000
6000
8000
10000
12000
Pack
ets t
o BS
LEACHSEP
PECRPImproved protocol
Figure 12 Comparison of packets sent to BS from CHs without power supply
times104
200
400
600
800
1000
1200
2000
1800
21000
1400
1600
Number of rounds
0
2
4
6
8
10
12
Pack
ets t
o CH
LEACHSEP
PECRPImproved protocol
Figure 13 Comparison of packets sent to CHs from member nodes without power supply
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
LEACHSEP
PECRPImproved protocol
Figure 14 Comparison of live nodes in each round with power supply
14 Journal of Electrical and Computer Engineering
Table 4 Statistics number of rounds of dead nodes of the four protocols with power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 177 204 232 341SEP 185 210 264 665PECRP 392 430 493 530FOI-LEACH 555 716 1238 2246
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
002
004
006
008
01
012
014
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 15 Comparison of average residual energy in each round with power supply
Table 5 Statistics of the average residual energy (J) of nodes of the four protocols with power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0086 0018 0 0SEP 0105 0036 0001 0PECRP 0099 007 0 0FOI-LEACH 0124 0109 0062 0001
0
1
2
3
4
5
6
7
8
Com
paris
on o
f CH
s in
each
regi
on
2 3 4 5 6 7 8 9 101Number of rounds
ABC
(a)
0
2
4
6
8
10
12
1415
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
Figure 16 Continued
Journal of Electrical and Computer Engineering 15
0
2
4
6
8
10
12
14
16N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14
16
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(d)
0
2
4
6
8
10
12
14
16
18
20
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 16 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol with power supply
0
2000
4000
6000
8000
10000
12000
14000
Pack
ets t
o BS
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 17 Comparison of packets sent to BS from CHs with power supply
16 Journal of Electrical and Computer Engineering
node e supplied energy promotes the extension of thenetwork lifetime and the stability of the networking for thefour protocols in varying degrees For the LEACH protocolthe node began to die at round 177 SEP protocol at round185 PECRP protocol at round 392 and round 555 for theimproved FOI-LEACH protocol
e distributions of the number of clusters in the fourprotocols with energy supply simulated for 10 rounds ofrandom elections are shown in Figure 16 Like the previousfigures Figure 16(a) represents the statistics number of CHsof each zone of FOI-LEACH protocol Figures 16(b)ndash16(e)represent the statistics number of CHs of FOI-LEACHprotocol LEACH protocol SEP protocol and PECRPprotocol respectively Due to the efficient schemes of CHselecting and clustering the FOI-LEACH protocol showssignificantly better performance than the other threeprotocols
(4) Network (roughput In the environment of self-energyas shown in Figure 17 the total number of packets sent toBS of the LEACH protocol SEP protocol PECRP protocoland the proposed FOI-LEACH protocol is approximately2428 3080 3746 and 13265 respectively Moreover inFigure 18 the total number of packages sent to CHs of theLEACH protocol SEP protocol PECRP protocol andFOI-LEACH protocol is approximately 21400 2430044000 and 123200 respectively We can find that the totalnumber of packets sent by our protocol to BS and CHs ismuch higher than the other protocols which also dem-onstrated that the proposed protocol has a better networkthroughout
6 Conclusions
According to the characteristics of field observation in-strument networking an improved protocol FOI-LEACHbased on LEACH protocol was proposed in this paper Byconsidering the energy factor in the CH election threshold
and referring to the SEP protocol to set up two kinds ofnodes with different initial energies which are calledadvanced nodes and normal nodes the network model offield observation instruments has been established Inaddition to solve the problem that the LEACH protocolconsumes much energy during transmission and results inuneven energy consumption for the direct and long-distance transmission the improved protocol adopted the3 zones of partitioning mechanism and the multihoptransmission mechanism to alleviate and avoid the ldquohotspotrdquo problems Furthermore energy supplies were addedto the nodes in A and B zones that are responsible formore energy transmission so as to balance the energyconsumption of the network and prolong the networklifetime In the simulation experiments we compared theperformance of the FOI-LEACH protocol with theLEACH SEP and PECRP protocols in two cases with orwithout energy supply Comparing performance indica-tors of network lifetime energy consumption rate sta-bility and network throughput the proposed FOI-LEACH protocol can slow down the death of nodes andthe energy consumption rate obviously and shows asignificantly better performance than other three proto-cols e experimental results demonstrated that the FOI-LEACH protocol could balance network energy con-sumption and alleviate the ldquohot spotrdquo problem to extendthe lifetime of network nodes in the field observationinstruments network e future work is to implementand port the improved protocol to the hardware of net-working node we designed and developed previously andtest and verify the feasibility and stability of the protocolin the actual situation
Data Availability
e initial nodes are generated randomly in the networkand there are no observation data used in the simulationexperiments
0
20000
40000
60000
80000
100000
120000
140000
Pack
ets t
o CH
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 18 Comparison of packets sent to CHs from nodes with power supply
Journal of Electrical and Computer Engineering 17
Conflicts of Interest
e authors declare that there are no conflicts of interest
Acknowledgments
is work was supported by the National Nature ScienceFoundation of China (Grant no 61862038) the LanzhouTalent Innovation and Entrepreneurship Technology PlanProject (no 2019-RC-14) and the Foundation of a HundredYouth Talents Training Program of Lanzhou JiaotongUniversity
References
[1] J Y Huo Z N Ren and Y R Yang A Kind of InstrumentNetwork Node Equipment and Monitoring System ChinesePatents Beijing China 2017
[2] J Y Huo Key Technology and Application Research ofE-Science Virtual Joint Observation System for Geoscience inCold and Dry Regions University of Chinese Academy ofSciences Beijing China 2012
[3] I F Akyildiz W L Weilian Su Y Sankarasubramaniam andE Cayirci ldquoA survey on sensor networksrdquo IEEE Communi-cations Magazine vol 40 no 8 pp 102ndash114 2002
[4] W R Heinzelman A Chandrakasan and H BalakrishnanldquoEnergy-efficient communication protocol for wirelessmicrosensor networksrdquo in Proceedings of the 33rd HawaiiIntentional Conference on System Sciences Maui HI USAJanuary 2000
[5] D Mehta and S Saxena ldquoA comparative analysis of energyefficient hierarchical routing protocols for wireless sensornetworksrdquo in Proceedings of the 2018 4th InternationalConference on Computing Sciences (ICCS) pp 53ndash58Jalandhar India August 2018
[6] C Karlof and D Wagner ldquoSecure routing in wireless sensornetworks attacks and countermeasuresrdquo Ad Hoc Networksvol 1 2003
[7] L B Oliveira A Ferreira M A Vilaca et al ldquoSecLEACH-onthe security of clustered sensor networksrdquo Signal Processingvol 87 2007
[8] Y Y Gu GW Bai and J J Tao ldquoAZM-LEACH autonomouszone-based multi-hop routing protocol in WSNsrdquo ComputerEngineering and Applications vol 47 no 20 pp 58ndash61 2011
[9] L XWang Research on Routing Technology ofWireless SensorNetworks Based on Data Aggregation Shenyang LigongUniversity Shenyang China 2015
[10] J P Shao Research on Key Energy-Efficient Routing Tech-nology of WSN Based on Cluster Shenyang Ligong UniversityShenyang China 2015
[11] V K Arora V Sharma and M Sachdeva ldquoA survey onLEACH and otherrsquos routing protocols in wireless sensornetworkrdquo Optik vol 127 no 16 pp 6590ndash6600 2016
[12] W B Heinzelman A P Chandrakasan and H BalakrishnanldquoAn application-specific protocol architecture for wirelessmicrosensor networksrdquo IEEE Transactions on WirelessCommunications vol 1 no 4 pp 660ndash670 2002
[13] S Al-Sodairi and R Ouni ldquoReliable and energy-efficientmulti-hop LEACH-based clustering protocol for wirelesssensor networksrdquo Sustainable Computing Informatics andSystems vol 20 pp 1ndash13 2018
[14] O Younis and S Fahmy ldquoHEED a hybrid energy-efficientdistributed clustering approach for ad hoc sensor networksrdquo
IEEE Transactions on Mobile Computing vol 3 no 4pp 366ndash379 2004
[15] B B Chen and Y L Shi ldquoWSN routing protocol based oncluster heads selection in regionsrdquo Computer Engineeringvol 37 no 19 pp 96ndash98 2011
[16] P Azada ldquoCluster head selection in wireless sensor networksunder fuzzy environmentrdquo ISRN Sensor Networks vol 2013Article ID 909086 8 pages 2013
[17] S Soro and W B Heinzelman ldquoCluster head election tech-niques for coverage preservation in wireless sensor networksrdquoAd Hoc Networks vol 7 no 5 pp 955ndash972 2009
[18] A akkar ldquoDEAL distance and energy based advancedleach protocolrdquo in Proceedings of the International Conferenceon Information and Communication Technology for IntelligentSystems pp 370ndash376 Ahmedabad India March 2017
[19] T Y Chang W N Liu Y Zhang and H Y Li ldquoOptimizedLEACH protocol based on distance and energy of clusterheadrdquo Journal of Hebei University (Natural Science Edition)vol 39 no 2 pp 194ndash200 2019
[20] P Mehra M Doja and B Alam ldquoStability enhancement inLEACH (SE-LEACH) for homogeneousWSNrdquo EAI EndorsedTransactions on Scalable Information Systems vol 6 no 20pp 1ndash9 2019
[21] G Smaragdakis I Matta and A Bestavros ldquoSEP a stableelection protocol for clustered heterogeneous wireless sensornetworksrdquo in Proceedings of the Second InternationalWorkshop on Sensor and Actor Network Protocols and Ap-plications (SANPA 2004) pp 1ndash11 Boston MA USA June2004
[22] F S Hu and Q Xiao ldquoMulti-hop routing algorithm of energy-balancing based on LEACHrdquo Journal of Chinese ComputerSystems vol 35 no 1 pp 72ndash75 2014
[23] C F Li M Ye G H Chen and J Wu ldquoAn energy-efficientunequal clustering mechanism for wireless sensor networksrdquoin Proceedings of the IEEE International Conference on MobileAdhoc and Sensor Systems Conference p 604 WashingtonDC USA November 2005
[24] E Alnawafa I Marghescu and MHT ldquoMulti-hop techniquefor the improvement of leach protocolrdquo in Proceedings of the2016 15th RoEduNet Conference Networking in Education andResearch pp 1ndash5 Bucharest Romania September 2016
[25] E Alnawafa and I Marghescu ldquoIMHT improved MHT-LEACH protocol for wireless sensor networksrdquo in Proceedingsof the 2017 8th International Conference on Information andCommunication Systems (ICICS) pp 246ndash251 Irbid JordanApril 2017
[26] J Y Huo Z Zhang and C Tao ldquoUsing IPv6 address ad-vantage to build Network Node of Field observation In-struments in cold and arid areasrdquo China Education Networkno 5 pp 45-46 2018
[27] L Mateu and F Moll ldquoReview of energy harvesting tech-niques and applications for microelectronicsrdquo in Proceedingsof the International Society for Optical Engineering pp 359ndash373 Bellingham WA USA October 2005
[28] G Wang and R Y Wang ldquoRouting algorithm based oncluster-head optimization for self-energized wireless sensornetworkrdquo Journal of Computer Applications vol 38 no 334pp 201ndash216 2018
[29] X P Fan X Yang S Q Liu and Z H Qu ldquoClusteringrouting algorithm for wireless sensor networks with powerharvestingrdquo Computer Engineering vol 39 no 11 pp 126ndash134 2008
18 Journal of Electrical and Computer Engineering
[30] C H Zhang ldquoStudy on the energy heterogeneous clusteringrouting protocol for wireless sensor networksrdquo Science ampTechnology Vision no 13 pp 71+164ndash165 2012
[31] T Liu and F Li ldquoPower-efficient clustering routing protocolbased on applications in wireless sensor networkrdquo in Pro-ceedings of the International Conference on Wireless Com-munications IEEE Press Melbourne Australia September2009
Journal of Electrical and Computer Engineering 19
divided into two stages the establishment stage of the clusterand the stable transmission stage [10]
In the establishment stage of the cluster each nodegenerates a random number from 0 to 1 and the thresholdT(n) is calculated according to equation (1) en therandom number generated by each node is compared withT(n) If the value is less than T(n) the node is selected as theCH
T(n)
p
1 minus plowast (rmod((1p))) n isin G
0 n notin G
⎧⎪⎪⎪⎨
⎪⎪⎪⎩
(1)
where p is the percentage of CH in all nodes r is the numberof current election rounds rmod (1p) is the number ofnodes that have been selected in this round and G is the setof nodes without CHs selected in this round After the end ofeach CH selection round each selected CH broadcasts itsmessage of becoming a CH to other nodes After receivingthe broadcast message other nodes choose to join a clusteraccording to the received signal strength and send theirjoining message to the selected CH [11] Each CH createsand assigns a TDMA schedule between each member nodeafter its member nodes are joined en end the clusterestablishment stage and start the data transmission stage
In the data transmission stage each member node sendsdata to the CH within its allocated period and the CHtransmits data to the BS after data fusion erefore CHsconsume more energy than member nodes LEACH ensuresthat all nodes are equally likely to act as CHs employing cyclecirculation so that the nodes consume energy in a relativelybalanced manner However factors such as residual energyof nodes and distance from the BS are still not considerede randomness of the CH election may lead to the death ofthe CH far away from the BS due to the rapid exhaustion ofenergy which affects the survival time of the whole network
To address these issues the researchers have proposedmany improvements to the LEACH protocol for each stageHowever because of the difficulty high cost and time-consuming problems of deploying nodes in the field theresearchers use MATLAB NS2 OMNeT++ OPNET andother simulation software to simulate the network whichcan provide objective and reliable data for network planningand design shorten the network simulation time and reducethe investment cost In this paper we will use the MATLABsimulation platform to test and evaluate experimentalperformance Heinzelman et al proposed a centralizedLEACH (C-LEACH) to improve the LEACH protocolperformance Instead of sensor nodes themselves the sinkselects CHs in C-LEACH and the algorithm gives betterresults than the LEACH algorithm [12] In the case of CHelection one improvement scheme is to improve thethreshold T(n) For example Sara al-sodairi considered thecurrent residual energy of nodes to reduce the possibilitythat nodes with less energy are selected as CHs [13]However as the network runs for a long time all the sur-viving nodes will have less energy e correspondingthreshold T(n) also becomes smaller that is the probability
of ordinary nodes being selected as CHs becomes smallerand the number of CHs selected in each round decreasessuccessively which leads to unbalanced network energyconsumption and shorter network survival time Lots ofresearchers put forward methods for the cluster headelection by considering more factors In the hybrid energy-efficient distributed (HEED) protocol cluster heads areselected based on the nodesrsquo remaining energy and nodedegree [14] HEED can asymptotically almost surely guar-antee connectivity of clustered networks and simulationresults demonstrated that it is effective in prolonging thenetwork lifetime and supporting scalable data aggregationBinbing Chen considered the current residual energy of thenode and considered the current average energy of thenetwork [15] As the nodersquos current energy value is less thanthe average energy value it cannot be selected as the CHCompared with the original LEACH protocol better qualitynodes can be selected as CHs which can improve networkperformance and prolong the network life cycle to someextent However it does not prevent the CH from con-sumingmore energy due to the heavy load and long-distancecommunication In [16] fuzzy multiple attribute decision-making (MADM) approach is used to select CHs using threecriteria including residual energy number of neighbors andthe distance from the base station of the nodes e sim-ulation results demonstrated that it is more effective inprolonging the network lifetime in homogeneous environ-ments Soro and Heinzelman proposed cluster head electiontechniques for coverage preservation in WSN based on a setof coverage-aware cost metrics that favor nodes deployed indensely populated network areas as better candidates forcluster head nodes active sensor nodes and routers [17]Compared with the traditional energy-based selectionmethods the methods can increase the clustered sensornetwork lifetimeakkar took into account the factors suchas residual energy the mean value and standard deviation ofthe current network energy and the distance from the nodeto the BS [18] e added energy factor and distance factorcan make the network energy change relatively stable andthe nodes close to the BS are more likely to be selected asCHs so the energy consumption of CHs is relatively bal-anced Compared with the original LEACH the protocol hasa longer stable period and enhances the network stabilityHowever due to the randomness of the clusters generated ineach round the maximum and minimum clusters may beformed making the distribution of network energy con-sumption unreasonable and shortening the network lifecycle In [19] Chang et al solved the possibility of minimumclusters and maximum clusters In the clustering stage thenode selects the CH according to the received broadcastsignal strength and adds a parameter based on the clusteringe parameter comprehensively takes into account thedistance between the node to each CH and the energy factorsof the CHe algorithm can optimize the clustering processto reduce the occurrence of extreme cases such as maximumand minimum clusters and form a more reasonable clusterIt makes the distribution of energy consumption morereasonable and prolongs the life cycle of the network Mehraet al proposed the SE-LEACH protocol in [20] which
Journal of Electrical and Computer Engineering 3
considers the node density residual energy distance fromthe BS and power consumption in selecting the CH At thesame time the non-CH selects the CH according to theresidual energy node density the power dissipated by theCH in the process of operation and the distance to the CHis protocol can increase the stable area of WSN balancethe load and ensure that all nodes similarly consume power
Some scholars have also proposed routing protocols forheterogeneous network structures Smaragdakis et al pro-posed a stable heterogeneous election protocol SEP [21] Inthe SEP protocol two kinds of nodes with different initialenergy are proposed which are the normal node with lessinitial energy and the advanced node with more initialenergy e advanced node is more likely to become a CHthan a normal node In general as the initial energy of thenetwork increases the overall lifetime of the network alsoincreases and the instability period decreases Howeverfactors such as energy and distance are not taken into ac-count in the CH election process so that the energy con-sumption of CH is not balanced
In the improved scheme of intercluster communicationHu and Xiao constructed intercluster multihop routing bycombining the idea of node chain in the PEGASIS protocol[22] Finally the node acting as a Leader on the chainundertakes the task of communication with the BS eprotocol reduces the energy consumed by direct commu-nication between multiple CHs and the BS in the LEACHprotocol At the same time the multihop transmissionbetween CHs also enhances the scalability of the network Liet al considered the ldquohot spotrdquo problem in multihop wirelesssensor networks [23]e hot spot problem refers to that theCH closer to the BS needs to bear more relay traffic thanother CHs leading to the premature death of the CH closerto the BS resulting in the exposure of the network area andpartitioning of network us the author divides the nodesinto clusters of different sizes e cluster radius increaseswith the distance between the CH and the BS In this way theCHs close to the BS bear less relay traffic which relativelybalances the network energy consumption and extends thenetwork life Furthermore in [24] the MHT-LEACHmethod proposed by Emad Alnawafa can determine whetherit is possible to transmit their data to BS through inter-mediate nodes according to its location and distance fromBS Compared with the LEACH protocol MHT-LEACHimproves network life stability and throughput enAlnawafa and Marghescu proposed the IMHT-LEACHmethod in [25] to solve the problem that MHT-LEACHrequires a large amount of energy to transfer data to the CHof the inner group IMHT-LEACH can reduce the energycost of data transfer to BS especially in the huge deploymentarea or the large distance from the sensor area to BSCompared with LEACH and MHT-LEACH protocolsIMHT-LEACH protocol can prolong the lifetime improvethe stability period and increase the throughput of thesensor network
ese protocols significantly reduce energy consump-tion in the data transmission phase but consume muchenergy in the process of establishing routing While ensuringhigh efficiency the efforts must be taken to avoid consuming
too much energy in establishing routes erefore we havemade the following contributions
(1) First of all we consider the factors such as energy inthe cluster head election stage and the clusteringstage solve the energy balance and ldquohot spotrdquoproblems and reduce the risk of premature death ofthe network
(2) en the regional autonomous intercluster multi-hop routing mechanism is adopted in the datatransmission phase to solve the problem of prema-ture death of nodes and achieve the purpose ofbalancing network energy consumption
(3) Finally simulation experiments are carried out onthe protocol and the results show that the networklifetime energy consumption rate stability andthroughput have been improved
3 FOI-LEACH Routing Protocol
Compared with WSNs the network of field observationinstruments is connected with data acquisition equipmentby network nodes Data acquisition instruments are gen-erally connected with several or dozens of sensor devices[26] which can observe a large number of observation el-ements It has the characteristics of large data storagecomplex network structure and so on e network hasrelatively few nodes which have strong processing capacityto process data and instructions to complete the commu-nication with the data acquisition equipment and othertasks ere is auxiliary power supply from solar cells fornetworking nodes but because the field observation in-strument networks are usually deployed in a harsh envi-ronment the problem of energy consumption must be fullyconsidered erefore we proposed an improved routingprotocol based on LEACH protocol to meet the needs of thefield observation instrument networking
31 Improvement in CH Election (reshold At the stage ofCH election the random election method of the originalLEACH protocol may let the nodes with less energy beselected as CHs leading to the premature death of net-working nodes To solve the energy consumption problem inthe harsh environment the energy factor of the node wasconsidered and the concept of ldquoself-energyrdquo was introducedto recharge the node With the continuous development andprogress of environmental energy collection technologyresearchers have been able to collect energy in the envi-ronment such as solar light mechanical vibration and heatand apply them to WSN [27] design sensors that can au-tomatically collect environmental energy e sensor nodecan convert the solar energy vibration energy and thermalenergy in the environment into usable electric energy andautomatically recharge energy for itself forming aWSNwiththe characteristics of self-energy [28] In order to achievelong-term observation and data transmission we adoptedthe solar cell power supply in the field observation instru-ment network so that the energy of network nodes can be
4 Journal of Electrical and Computer Engineering
recharged Correspondingly the election threshold of CHs ismodified to reduce the possibility that nodes with lowerenergy are elected as CHs
e threshold formula of node i in round r is shown asfollows
T(i)
popt
1 minus popt times mod r round 1popt1113872 11138731113872 1113873
timesEr(i) + Eh(i r minus 1)
Eo
i isin G
0 i notin G
⎧⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎨
⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎩
(2)
where popt is the optimal probability of a node becoming aCH Eo is the initial energy of the node Er(i) is the residualenergy of the current node and Eh(i r minus 1) is the energyobtained by the current node in the previous round Sincethe energy acquisition environment of each node is notconstant the energy acquisition rate of node i in k units oftime is denoted as αi(k) and the energy acquired by node iin the rminus 1 round [29] is denoted in the following equation
Eh(i r minus 1) 1113944
T(r)
kT(rminus1)
αi(k) (3)
According to the above analysis in the CH election theimproved threshold should consider the total number ofCHs needed by the network and the number of times eachnode has become a CH as well as the initial energy value ofthe node the residual energy value of the node in theprevious round and the supplied energy value of the nodeIn the process of cluster establishment of the r round eachnode firstly needs to count the initial energy value and thecurrent residual energy value and calculate the energy valueobtained in the previous round according to the energyrecharging status If the residual energy and recharge energyof the node are both low the probability of the node be-coming a CH in the r+ 1 round is reduced to avoid its deathdue to excessive energy consumption On the contrary whenthe residual energy and replenishment energy of the nodeare sufficient the probability of the node becoming a CH isincreased
32 Improvement in ClusteringMethod After the election ofthe CH the clustering operation is performed Since theLEACH protocol divides the network into clusters of equalsize the CHs near the BS not only have to bear the energyconsumed by the data transmission within their clusters butalso the forwarding energy brought by the CHs far awayfrom the BS which leads to unbalanced traffic load betweennodes and form a ldquohot spotrdquo problem In order to alleviateand avoid the ldquohot spotrdquo problem an energy-efficient andbalanced network clustering routing protocol for observa-tion instruments in harsh areas is constructed In the routingprotocol clusters of unequal sizes are constructed and thesize of the cluster is proportional to the distance between theCH and the BS In other words the closer it is to the BS the
smaller the cluster is and it consumes less energy in thecommunication within the cluster and more energy in theintercluster communication On the contrary the fartheraway from the BS the larger the cluster is and the more theenergy it consumes is concentrated in the communicationwithin the cluster Moreover since the node has differentenergy levels in the heterogeneous network not only thedistance between the node and the BS but also the currentresidual energy and recharge energy of the node should beconsidered to calculate the competitive radius [30] whichwas shown in the following equation
Rc 1 minus α timesdmax minus d(i BS)
dmax minus dminminus β times 1 minus
Er(i) + Eh(i r minus 1)
Eo
1113888 11138891113890 1113891 times R0c
(4)
in which α and β are the weighted factors of the value in [01] and satisfy the condition that α + β 1R0
c is the maxi-mum competitive radius dmax and dmin are the maximumand minimum values from nodes to BS in the networkd(i BS) is the distance between the current node i and theBS By dividing the network into clusters of different sizesaccording to the distance from the nodes to the BS thecurrent residual energy and the supply energy of the nodesthe CHs near or far away the BS consume approximatelyequal energy so as to achieve the purpose of energy balancein the field instrument network
33 Improvement in Communication Method After theelection of CHs and the formation of clusters the networkenters the stable transmission stage In general the time ofstable transmission is longer than that of cluster formationIn the LEACH protocol data transmission is a single-hoptransmission at is all member nodes send the collecteddata information to the CH of the cluster and the CH sendsit to the BS after data fusion is causes the CH far awayfrom the BS to consumemore energy so that it may die in thetransmission process and fail to transmit data successfullywhich significantly reduces the network efficiency ere-fore a multihop approach to data transmission was con-sidered and the concept of ldquozonerdquo was introduced in thispaper e zone especially refers to the ring bands formed bytaking the BS as the center of the circle and the adjacentcircumferential lines with different lengths as the radius Azone can contain several clusters and a cluster must belongto a specific zone [8] e BS controls the transmissionenergy broadcasts the information of different intensitiesand divides the monitoring area into three-ring zones A Band C as shown in Figure 2 e data communicationmethod adopts the principle of nearest partitioning that isthe CH in zone C selects the CH closest to it in zone B as thenext hop Similarly the CH in zone B selects the nearest CHin zone A as the next hop e CH in zone A communicatesdirectly with the BS According to the characteristics ofpartitioning because cluster nodes in zone A and zone Bneed to bear more energy consumed by data fusion andforwarding only the nodes in zone A and zone B arepowered by solar cells
Journal of Electrical and Computer Engineering 5
34 Analysis of Heterogeneity In this paper in order toprolong the stable stage of the network we adopted the valueof heterogeneity set in literature [21] to set up two kinds ofnodes with different initial energies namely the normalnodes with lower initial energy and the advanced nodes withhigher initial energy Advanced nodes are more likely tobecome CHs and not easy to die than normal nodes which isto balance energy consumption At the same time the totalenergy of the network has changed If the initial energy of thenormal node is Eo the initial energy of the advanced node is(1 + a) middot Eo So the total energy of the network is changed to(1 minus m) middot Eo + m middot (1 + a) middot Eo (1 + a middot m) middot Eo that is thetotal energy of the network has increased by 1 + am timesAccordingly in the CH election the optimal probability ofthe node becoming the CH has also been changed e
weighted probabilities of normal nodes and advanced nodesare shown in the following equations respectively
pnrm popt
1 + α middot m (5)
padv popt
1 + αmtimes(1 + a) (6)
e optimal CH number is kopt n2π
radicmiddot
EfsEmp
1113969middot
md2toBS [30] where kopt represents the optimal cluster
number n is the number of nodes set in the monitoring areaMtimesM and dtoBS represents the distance between the CHand the BS
For normal nodes the modified election threshold isshown in equation (7) Similarly the election threshold foradvanced nodes is shown in equation (8)
T(i)
pnrm
1 minus pnrm times mod r round 1pnrm( 1113857( 1113857times
Er(i) + Eh(i r minus 1)
Eo
i isin G
0 i notin G
⎧⎪⎪⎪⎪⎨
⎪⎪⎪⎪⎩
(7)
T(i)
padv
1 minus padv times mod r round 1padv( 1113857( 1113857times
Er(i) + Eh(i r minus 1)
Eo
i isin G
0 i notin G
⎧⎪⎪⎨
⎪⎪⎩(8)
In the above two threshold equations it can be foundthat the weighted probabilities are different because theadvanced node has more initial energy Due to the energyfactor is taken into account when electing the CH the higherthe energy is the easier it is to become the CH so theadvanced nodes are more likely to become the CHs than thenormal nodes
35 FOI-LEACH Routing Protocol FOI-LEACH protocolintroduces the concepts of ldquoself-energizedrdquo and ldquozonerdquocombined with the characteristics of field instrument net-working In addition the CH election stage and cluster
formation stage are carried out in each zone respectivelye flow of each round of the FOI-LEACH protocol isshown in Figure 3 and the specific operation steps aredescribed as follows
(1) After the deployment of the network nodes eachnode estimates the distance from the BS according tothe signal strength transmitted by the BS judges andidentifies the zone to which it belongs
(2) At the beginning of the CH election the nodegenerates a random number from 0 to 1 counts thecurrent residual energy Er(i) and the previous roundof energy replenishment Eh(i r minus 1) and determines
ABC
Figure 2 Partitioning method in the routing protocol
6 Journal of Electrical and Computer Engineering
whether the node is an advanced node Moreover ifit is an advanced node it calculates the threshold asshown in equation (8) otherwise it calculates thethreshold as shown in equation (7) and then judgeswhether the random number generated by the nodeis lower than the threshold if so announce themessage that it becomes the CH otherwise it be-comes a member node and waits for the schedulingof the CH
(3) After the CH election according to the BS radiomessage all the nodes maximum distance dmax andminimum dmin of network nodes to the BS and thedistance d(i BS) of the current node to the BS arestatistically counted and the current residual energy ofthe node Er(i) and the energy supply of the previousround Eh(i r minus 1) are calculated and then clustercompetition radii are computed e node detects thereceived announcement message and determineswhether the CH exists within the competition radiusof the zone If so a CH is selected according to thecompetition radius to join and form a cluster If thereis no CH within the competitive radius it automat-ically becomes a CH and publishes a notice
(4) After the cluster is formed the CH creates a TDMAschedule and the member nodes in the cluster waitfor the CH to be scheduled
(5) In the data transmission stage cluster member nodescollect data regularly and send the data directly to theCH through the single-hop transmission e CHcompresses and fuses the received data and thensends it to the nearest CH in the next zone until it istransmitted to the BS Loop through steps 1 to 5 untilthe network fails
4 Network Model of FieldObservation Instruments
41 Network Model In this paper we consider the randomdeployment of n nodes in a square monitoring area with asize of MtimesM e assumptions for the networking envi-ronment are as follows
All networking nodes have unique IDs and areheterogeneousAll networking nodes are randomly deployed in themonitoring area and cannot be moved afterdeploymentAll networking nodes know their residual energy andsome nodes can supplement the energyAll networking nodes can determine the distance fromthe information source according to the intensity of thereceived information
Start
Base station broadcastscluster head election
Node i generatesrandom number t (01)
Is it an advancednode
Becomes the ordinary node and waits for the cluster head node
to broadcast information
Yes
Request to join the nearest cluster
Enter the data transfer phasepartition autonomous multihop
mechanism
Waiting for the scheduling of the cluster head
Cluster headselection
The formationof the cluster
Create aschedule
Datatransmission
After a period oftime
NotltT(n)nrm tltT(n)advYes
Becomes the clusterhead nodes and
broadcasts the message
Waiting for theordinary node to
request to join
Create the TDMAschedule table
Yes
No No
The node performsself-energizing
End
Becomes the clusterhead node and
broadcasts the message
Waiting for theordinary node to
request to join
Create the TDMAschedule table
Figure 3 Flow chart of operation in each round of FOI-LEACH protocol
Journal of Electrical and Computer Engineering 7
e BS is located outside the monitoring area it hassufficient energy resources and each node knows thelocation of the BS
42 Energy Model Energy consumption is an importantcriterion to evaluate the performance of a routing protocole network life mainly depends on the energy consumed indata sending and data receiving Meanwhile the energyconsumed by the CH when using the fusion technologyshould be considered and the energy consumption of thenode in the process of calculation and storage should beneglected LEACH protocol uses first-order wireless mode inWSNs so it adopts a simple energy consumptionmodel [12]e model defines that the energy consumed by each l bitdata sent by the wireless circuit is
ETx(l d) ETxminuselec(l d) + ETxminusamp(l d)
lEelec + lEfsd
2 dlt d0
lEelec + lEmpd4 dge d0
⎧⎨
⎩
(9)
When receiving information the energy consumed bythe wireless circuit receiving l bit data is
ERx(l d) ERxminuselec(l d) lEelec (10)
e energy consumed by data fusion is
EGx lEgather (11)
In equations (9)-(10) d represents the distance betweenthe sending node and the receiving node and Eelec representsthe energy consumed for each bit of data sent or received Inequation (9) Efsd
2 is the energy consumed by the free spacemodel for each l bit of data amplification and Empd4 is theenergy consumed by the multipath attenuation model foreach l bit of data amplification Obviously when the distancebetween nodes becomes more extensive the energy con-sumption increases exponentially erefore if you want toreduce the energy consumption of data transmission youmust reduce the distance between nodes e Egather inequation (11) is expressed as the energy consumed by datafusion for each processing of 1 bit the d0 in equation (9) is athreshold which is determined by the equation (12) and isdefined as 87m in this paper
d0
Efs
Emp
1113971
(12)
5 Simulation Experiments and Analysis
51 Experimental Setting In order to analyze the perfor-mance of the FOI-LEACH protocol this paper conductssimulation experiments onMATLAB simulation platform tocompare it with the original LEACH protocol [4] SEPprotocol [21] and PECRP protocol [31] e simulationexperiments were carried out under the monitoring area of100mtimes 100m and the BS is located outside the monitoringarea with the coordinate of (150 50) As shown in Figure 4
the initial node distribution map distinguishes the nodes ineach zone by color in which red represents the nodes in zoneA blue represents the nodes in zone B and the greenrepresents the nodes in zone C And ldquordquo means the normalnode ldquo+rdquo means the advanced node and ldquotimesrdquo means BS
In the self-energy experiment all the surviving nodes inthe network are replenished with energy once every fiverounds until the simulation end e recharge energy isdistributed randomly to all remaining surviving nodes in thenetwork e total energy of the first replenishment is set to035 J In the later replenishment in order to prevent thenodes in the network from dying when there are too fewnodes We set the attenuation factor alpha to 09 that is theenergy replenishment to all the nodes in the network is 09times of the previous timee initial energy and topology ofall the experimental networks were set to the same envi-ronment When all the nodes in the network die the net-work is considered to be invalid Experiments proved thatthe network works best when the parameters are set to thefollowing valuesm is set to 01 a is set to 2 α is set to 03 andβ is set to 07e range of optimal CH number is [1 14] and10 is taken in this paper the probability of optimal CHnumber is popt 0 1 e three-partition system shown inFigure 2 was adopted in the routing protocol e specificparameters of the simulation experiments are listed inTable 1
52 Determination of the Partitioning Scheme e FOI-LEACH protocol proposed in this paper is based on theimprovement of the LEACH protocol In the initial stage ofnode deployment the distance between the node and the BSis obtained according to the signal strength of the BS re-ceived by the node en the monitoring area is partitionedaccording to the distance To determine the optimal parti-tioning scheme in the FOI-LEACH protocol we proposedthe following five schemes for the protocol and tested themin the partitioning experiment
Scheme 1 e monitoring area is divided into twozones A and B and the zone SA of A is equal to thezone SB of B as shown in Figure 5 (partitioning scheme1) e CH in zone B chooses the CH in zone A closest
0 50 100 1500
10
20
30
40
50
60
70
80
90
100
Advanced node
Normal node
BS
Figure 4 Distribution diagram of initial nodes
8 Journal of Electrical and Computer Engineering
to it for forwarding data and the CHs in zone Acommunicates directly with the BSScheme 2 As shown in Figure 5 (partitioning scheme2) the monitoring area is divided into two zones A andB and the SA of zone A is smaller than the area SB ofzone BScheme 3 e monitoring area is divided into threezones A B and C and the area SA of zone A is equalto the area SB of zone B and smaller than the area SC
of zone C as shown in Figure 5 (partitioning scheme3)Scheme 4 e monitoring area is divided into threezones A B and C and the area SA of zone A is smallerthan the area SB of zone B and smaller than the area SC
of zone C as shown in Figure 5 (partitioning scheme 4)Scheme 5 e monitoring area is divided into threezones A B and C and the area SA of zone A is equal tothe area SC of zone C and smaller than the area SB ofzone B as shown in Figure 5 (partitioning scheme 5)
e survival nodes and the average residual energy ineach round of the five partitioning schemes are drawn inFigures 6 and 7 respectively Based on the experimentalanalysis it can be found that Scheme 3 indicated as a redcurve in the figures has a better performance In scheme 3ie SA SB lt SC the first dead node appears in the 587thround which is later than other schemes that is thestability period is more extended than other schemes eaverage residual energy consumption rate of nodes is alsolower than that of other schemes is is because zones Aand B need to bear more forwarding energy so when thesetwo zones are smaller than zone C the network energyconsumption is more balanced erefore we adopted thepartitioning method of scheme 3 to carry out the simu-lation experiments
53 Analysis of Parameters In equation (4) parameters αand β determine the difference in cluster size erefore therelationship between these two parameters and network lifewas observed by taking α from 0 to 1 and β from 1 to 0 eresults of parameters analysis are shown in Figure 8 whichalso proves the rationality of our unequal clusteringmechanism When parameter α increases from 0 to 1 theeffect of the unequal clustering method is noticeableHowever the impact of parameter β on the network shouldalso be considered If the value of α is too large the lifetimeof the system will be shortened It is because too manyclusters will be generated near the BS and each cluster sendspackets to the BS which results in the waste of energyerefore it needs to determine the optimal values forparameters α and β In this experiment we can concludefrom Figure 8 that when α 0 3 and β 0 7 the death timeof the first node is later and the network is more stable
54 Experimental Comparison Analysis is paper mainlyevaluates the performance of the observation instrumentnetwork routing protocol with and without energy supplythrough the following evaluation elements
Network lifetime the network lifetime is measured bythe survival rate of the whole network nodes whichgenerally represents a certain proportion of the energyloss of the network node In this paper we took thedeath time interval from the beginning of the networkto the last surviving node as the lifetime of the networkEnergy consumption rate it usually refers to the av-erage energy consumption of a node sending or re-ceiving a byte of data It is essential to evaluate theperformance of routing algorithmsStability the stability of the field instruments obser-vation network was evaluated from two aspects thetime interval from the beginning of the network to thedeath of the first node and the number of CHsNetwork throughput the indicator to measure theefficiency of the network which is usually judged by thetotal number of packets sent to BS and the total numberof packets sent to CH
541 Experiments without Energy Supply
(1) Network Lifetime Figure 9 shows the number of sur-viving nodes in the network when the network runs for 2100rounds without being self-energized According to thestatistics of the number of rounds of death node in Table 2the network failure of the LEACH protocol occurs at round276 the network of SEP protocol expires at 462 rounds andnetwork failure of the PECRP protocol at round 438However the FOI-LEACH protocol was not expired untilround 2042 which significantly increased the networksurvival time It is because the FOI-LEACH protocol con-siders such factors as energy and distance in stages of CHelection cluster formation and intercluster communication
Table 1 Parameters in the simulation experiments
Parameter ValueTotal number of nodes N 100Network area (m) 100times100Coordinates of BS (m) (150 50)Data packet size L (bit) 4000Initial energy of normal node (J) 01Initial energy of advanced node (J) 03Energy consumption of transmitting circuit ETX (nJbit) 50
Energy consumption of receiving circuit ERX (nJbit) 50Free space model energy Efs (pJbitm
2) 10Multipath attenuation model energy Emp (pJbitm2) 00013Energy consumption of data fusion EDA (nJbit) 5Probability of the optimal number of CHs popt 01Maximum cluster radius in zone A RcA (m) 125Maximum cluster radius in zone B RcB (m) 125Maximum cluster radius in zone C RcC (m) 25Attenuation factor alpha 09M 01A 2α 03β 07
Journal of Electrical and Computer Engineering 9
AB
(a)
AB
(b)
ABC
(c)
ABC
(d)
ABC
(e)
Figure 5 Partitioning scheme (a) Partitioning scheme 1 SaltSb (b) Partitioning scheme 2 SaSb (c) Partitioning scheme 1 SaSbltSc (d)Partitioning scheme 1 SaltSbltSc (e) Partitioning scheme 1 SaScltSb
AeqBAsBAeqBsC
AsBsCAeqCsB
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
Figure 6 Comparison of active nodes in each round
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
002
004
006
008
01
012
Ave
rage
resid
ual e
nerg
y
AeqBAsBAeqBsC
AsBsCAeqCsB
Figure 7 Comparison of average residual energy in each round
10 Journal of Electrical and Computer Engineering
(2) Average Residual Energy and Energy Dissipation RateFigure 10 shows the graph of the average residual energy ofthe network running 2100 rounds without being self-en-ergized Combined with the network average residual en-ergy which is shown in Table 3 it can be drawn that the FOI-LEACH protocol is more slowly energy consumed Besidesit can be seen from Figure 10 that the energy consumption
rate of the improved network is significantly reduced toachieve the purpose of delaying energy consumption andextending network life
(3) Stability e stability of networking was evaluated fromtwo aspects First it can be seen from Figure 9 that the FOI-LEACH protocol significantly extends the death time of the
Self-energized
400
420
440
460
480
500
520
540
Dea
th ti
me o
f the
firs
t nod
e
01 02 03 04 05 06 07 08 09 10α
Figure 8 Impact of parameters α and β on the network lifetime
LEACHSEP
PECRPImproved protocol
400
160060
0
2000
1000
1200
140020
0
1800
21000
800
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
Figure 9 Comparison of live nodes in each round without power supply
Table 2 Statistics number of rounds of dead nodes of the four protocols without power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 135 160 204 276SEP 174 191 226 462PECRP 338 374 412 438FOI-LEACH 481 684 1272 2042
Journal of Electrical and Computer Engineering 11
first node For the LEACH protocol the nodes began to dieat round 135 SEP protocol at round 174 and PECRPprotocol at round 338 Because the energy factor is takeninto account in selecting the CH energy and distance factorsare taken into account in clustering and the adopted zone-based autonomous multihop communication model mini-mizes the Hello control package the nodes die at round 481for the FOI-LEACH protocol As a result the FOI-LEACHprotocol has better performance than other protocols
Figure 11 shows the distribution of the number ofclusters of the four protocols without energy supply simulatedfor 10 rounds of random elections in which Figure 11(a)represents the statistics number of CHs in each zone of theFOI-LEACH protocol and Figure 11(b) represents the sta-tistics number of CHs in the whole network of FOI-LEACHprotocol Figures 11(c)ndash11(e) represent the statistics numberof CHs of LEACH SEP and PECRP protocols respectively Itcan be seen that the number of CHs of FOI-LEACH protocolis more stable than that of LEACH SEP and PECRP BecauseLEACH and SEP randomly select CHs the number of CHsproduced was unstable e FOI-LEACH protocol formsclusters by selecting CHs with a competitive radius and thenumber of CHs is relatively stable
(4) Network (roughput Figure 12 shows that in theLEACH protocol SEP protocol PECRP protocol and ourproposed FOI-LEACH protocol the total number of packets
sent to BS is approximately 900 2580 2980 and 11140respectively Moreover Figure 13 shows that in the LEACHprotocol SEP protocol PECRP protocol and FOI-LEACHprotocol the total number of packages sent to CHs is ap-proximately 7500 21000 38200 and 119000 respectively Itis because the proposed scheme has a high network lifetimethe total number of packets sent to BS and CHs is muchhigher than other protocols
542 Experiments with Energy Supply
(1) Network Lifetime Figure 14 shows the number of sur-viving nodes in the network when the network runs for 2300rounds self-energized According to the statistics of deathnodes in Table 4 we can find that the network lifetime of thefour protocols all has been extended e network failure ofthe LEACH protocol occurred at round 341 the network ofthe SEP protocol expires at round 665 and network failure ofPECRP protocol at round 530 and the FOI-LEACH pro-tocol was not expired until round 2246 which significantlyincreased the network survival time It is demonstrated thatthe improved schemes can work well in both the environ-ments with or without power supply
(2) Average Residual Energy and Energy Dissipation RateFigure 15 shows the graph of the average residual energy ofthe network running 2300 rounds self-energized Combinedwith the network average residual energy which shown inTable 5 it can be drawn that the FOI-LEACH protocol ismore slowly energy consumed Besides it can be seen fromFigure 15 that the energy consumption rate of the improvednetwork is significantly reduced to achieve the purpose ofdelaying energy consumption and extending network life
(3) Stability For the stability of field instruments net-working it can be seen from Figure 14 that the FOI-LEACHprotocol significantly extends the death time of the first
1800
2000
1000
1600
210060
0
200
8000
120040
0
1400
Number of rounds
0
002
004
006
008
01
012
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 10 Comparison of average residual energy in each round without power supply
Table 3 Statistics of the average residual energy (J) of nodes of thefour protocols without power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0075 0007 0 0SEP 0094 002 0 0PECRP 0088 0053 0 0FOI-LEACH 0113 0092 0043 152times10minus5
12 Journal of Electrical and Computer Engineering
ABC
0
1
2
3
4
5
6
7Co
mpa
rison
of C
Hs i
n ea
ch re
gion
2 3 4 5 6 7 8 9 101Number of rounds
(a)
0
2
4
6
8
10
12
14
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(d)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 11 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol without power supply
Journal of Electrical and Computer Engineering 13
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
2000
4000
6000
8000
10000
12000
Pack
ets t
o BS
LEACHSEP
PECRPImproved protocol
Figure 12 Comparison of packets sent to BS from CHs without power supply
times104
200
400
600
800
1000
1200
2000
1800
21000
1400
1600
Number of rounds
0
2
4
6
8
10
12
Pack
ets t
o CH
LEACHSEP
PECRPImproved protocol
Figure 13 Comparison of packets sent to CHs from member nodes without power supply
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
LEACHSEP
PECRPImproved protocol
Figure 14 Comparison of live nodes in each round with power supply
14 Journal of Electrical and Computer Engineering
Table 4 Statistics number of rounds of dead nodes of the four protocols with power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 177 204 232 341SEP 185 210 264 665PECRP 392 430 493 530FOI-LEACH 555 716 1238 2246
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
002
004
006
008
01
012
014
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 15 Comparison of average residual energy in each round with power supply
Table 5 Statistics of the average residual energy (J) of nodes of the four protocols with power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0086 0018 0 0SEP 0105 0036 0001 0PECRP 0099 007 0 0FOI-LEACH 0124 0109 0062 0001
0
1
2
3
4
5
6
7
8
Com
paris
on o
f CH
s in
each
regi
on
2 3 4 5 6 7 8 9 101Number of rounds
ABC
(a)
0
2
4
6
8
10
12
1415
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
Figure 16 Continued
Journal of Electrical and Computer Engineering 15
0
2
4
6
8
10
12
14
16N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14
16
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(d)
0
2
4
6
8
10
12
14
16
18
20
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 16 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol with power supply
0
2000
4000
6000
8000
10000
12000
14000
Pack
ets t
o BS
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 17 Comparison of packets sent to BS from CHs with power supply
16 Journal of Electrical and Computer Engineering
node e supplied energy promotes the extension of thenetwork lifetime and the stability of the networking for thefour protocols in varying degrees For the LEACH protocolthe node began to die at round 177 SEP protocol at round185 PECRP protocol at round 392 and round 555 for theimproved FOI-LEACH protocol
e distributions of the number of clusters in the fourprotocols with energy supply simulated for 10 rounds ofrandom elections are shown in Figure 16 Like the previousfigures Figure 16(a) represents the statistics number of CHsof each zone of FOI-LEACH protocol Figures 16(b)ndash16(e)represent the statistics number of CHs of FOI-LEACHprotocol LEACH protocol SEP protocol and PECRPprotocol respectively Due to the efficient schemes of CHselecting and clustering the FOI-LEACH protocol showssignificantly better performance than the other threeprotocols
(4) Network (roughput In the environment of self-energyas shown in Figure 17 the total number of packets sent toBS of the LEACH protocol SEP protocol PECRP protocoland the proposed FOI-LEACH protocol is approximately2428 3080 3746 and 13265 respectively Moreover inFigure 18 the total number of packages sent to CHs of theLEACH protocol SEP protocol PECRP protocol andFOI-LEACH protocol is approximately 21400 2430044000 and 123200 respectively We can find that the totalnumber of packets sent by our protocol to BS and CHs ismuch higher than the other protocols which also dem-onstrated that the proposed protocol has a better networkthroughout
6 Conclusions
According to the characteristics of field observation in-strument networking an improved protocol FOI-LEACHbased on LEACH protocol was proposed in this paper Byconsidering the energy factor in the CH election threshold
and referring to the SEP protocol to set up two kinds ofnodes with different initial energies which are calledadvanced nodes and normal nodes the network model offield observation instruments has been established Inaddition to solve the problem that the LEACH protocolconsumes much energy during transmission and results inuneven energy consumption for the direct and long-distance transmission the improved protocol adopted the3 zones of partitioning mechanism and the multihoptransmission mechanism to alleviate and avoid the ldquohotspotrdquo problems Furthermore energy supplies were addedto the nodes in A and B zones that are responsible formore energy transmission so as to balance the energyconsumption of the network and prolong the networklifetime In the simulation experiments we compared theperformance of the FOI-LEACH protocol with theLEACH SEP and PECRP protocols in two cases with orwithout energy supply Comparing performance indica-tors of network lifetime energy consumption rate sta-bility and network throughput the proposed FOI-LEACH protocol can slow down the death of nodes andthe energy consumption rate obviously and shows asignificantly better performance than other three proto-cols e experimental results demonstrated that the FOI-LEACH protocol could balance network energy con-sumption and alleviate the ldquohot spotrdquo problem to extendthe lifetime of network nodes in the field observationinstruments network e future work is to implementand port the improved protocol to the hardware of net-working node we designed and developed previously andtest and verify the feasibility and stability of the protocolin the actual situation
Data Availability
e initial nodes are generated randomly in the networkand there are no observation data used in the simulationexperiments
0
20000
40000
60000
80000
100000
120000
140000
Pack
ets t
o CH
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 18 Comparison of packets sent to CHs from nodes with power supply
Journal of Electrical and Computer Engineering 17
Conflicts of Interest
e authors declare that there are no conflicts of interest
Acknowledgments
is work was supported by the National Nature ScienceFoundation of China (Grant no 61862038) the LanzhouTalent Innovation and Entrepreneurship Technology PlanProject (no 2019-RC-14) and the Foundation of a HundredYouth Talents Training Program of Lanzhou JiaotongUniversity
References
[1] J Y Huo Z N Ren and Y R Yang A Kind of InstrumentNetwork Node Equipment and Monitoring System ChinesePatents Beijing China 2017
[2] J Y Huo Key Technology and Application Research ofE-Science Virtual Joint Observation System for Geoscience inCold and Dry Regions University of Chinese Academy ofSciences Beijing China 2012
[3] I F Akyildiz W L Weilian Su Y Sankarasubramaniam andE Cayirci ldquoA survey on sensor networksrdquo IEEE Communi-cations Magazine vol 40 no 8 pp 102ndash114 2002
[4] W R Heinzelman A Chandrakasan and H BalakrishnanldquoEnergy-efficient communication protocol for wirelessmicrosensor networksrdquo in Proceedings of the 33rd HawaiiIntentional Conference on System Sciences Maui HI USAJanuary 2000
[5] D Mehta and S Saxena ldquoA comparative analysis of energyefficient hierarchical routing protocols for wireless sensornetworksrdquo in Proceedings of the 2018 4th InternationalConference on Computing Sciences (ICCS) pp 53ndash58Jalandhar India August 2018
[6] C Karlof and D Wagner ldquoSecure routing in wireless sensornetworks attacks and countermeasuresrdquo Ad Hoc Networksvol 1 2003
[7] L B Oliveira A Ferreira M A Vilaca et al ldquoSecLEACH-onthe security of clustered sensor networksrdquo Signal Processingvol 87 2007
[8] Y Y Gu GW Bai and J J Tao ldquoAZM-LEACH autonomouszone-based multi-hop routing protocol in WSNsrdquo ComputerEngineering and Applications vol 47 no 20 pp 58ndash61 2011
[9] L XWang Research on Routing Technology ofWireless SensorNetworks Based on Data Aggregation Shenyang LigongUniversity Shenyang China 2015
[10] J P Shao Research on Key Energy-Efficient Routing Tech-nology of WSN Based on Cluster Shenyang Ligong UniversityShenyang China 2015
[11] V K Arora V Sharma and M Sachdeva ldquoA survey onLEACH and otherrsquos routing protocols in wireless sensornetworkrdquo Optik vol 127 no 16 pp 6590ndash6600 2016
[12] W B Heinzelman A P Chandrakasan and H BalakrishnanldquoAn application-specific protocol architecture for wirelessmicrosensor networksrdquo IEEE Transactions on WirelessCommunications vol 1 no 4 pp 660ndash670 2002
[13] S Al-Sodairi and R Ouni ldquoReliable and energy-efficientmulti-hop LEACH-based clustering protocol for wirelesssensor networksrdquo Sustainable Computing Informatics andSystems vol 20 pp 1ndash13 2018
[14] O Younis and S Fahmy ldquoHEED a hybrid energy-efficientdistributed clustering approach for ad hoc sensor networksrdquo
IEEE Transactions on Mobile Computing vol 3 no 4pp 366ndash379 2004
[15] B B Chen and Y L Shi ldquoWSN routing protocol based oncluster heads selection in regionsrdquo Computer Engineeringvol 37 no 19 pp 96ndash98 2011
[16] P Azada ldquoCluster head selection in wireless sensor networksunder fuzzy environmentrdquo ISRN Sensor Networks vol 2013Article ID 909086 8 pages 2013
[17] S Soro and W B Heinzelman ldquoCluster head election tech-niques for coverage preservation in wireless sensor networksrdquoAd Hoc Networks vol 7 no 5 pp 955ndash972 2009
[18] A akkar ldquoDEAL distance and energy based advancedleach protocolrdquo in Proceedings of the International Conferenceon Information and Communication Technology for IntelligentSystems pp 370ndash376 Ahmedabad India March 2017
[19] T Y Chang W N Liu Y Zhang and H Y Li ldquoOptimizedLEACH protocol based on distance and energy of clusterheadrdquo Journal of Hebei University (Natural Science Edition)vol 39 no 2 pp 194ndash200 2019
[20] P Mehra M Doja and B Alam ldquoStability enhancement inLEACH (SE-LEACH) for homogeneousWSNrdquo EAI EndorsedTransactions on Scalable Information Systems vol 6 no 20pp 1ndash9 2019
[21] G Smaragdakis I Matta and A Bestavros ldquoSEP a stableelection protocol for clustered heterogeneous wireless sensornetworksrdquo in Proceedings of the Second InternationalWorkshop on Sensor and Actor Network Protocols and Ap-plications (SANPA 2004) pp 1ndash11 Boston MA USA June2004
[22] F S Hu and Q Xiao ldquoMulti-hop routing algorithm of energy-balancing based on LEACHrdquo Journal of Chinese ComputerSystems vol 35 no 1 pp 72ndash75 2014
[23] C F Li M Ye G H Chen and J Wu ldquoAn energy-efficientunequal clustering mechanism for wireless sensor networksrdquoin Proceedings of the IEEE International Conference on MobileAdhoc and Sensor Systems Conference p 604 WashingtonDC USA November 2005
[24] E Alnawafa I Marghescu and MHT ldquoMulti-hop techniquefor the improvement of leach protocolrdquo in Proceedings of the2016 15th RoEduNet Conference Networking in Education andResearch pp 1ndash5 Bucharest Romania September 2016
[25] E Alnawafa and I Marghescu ldquoIMHT improved MHT-LEACH protocol for wireless sensor networksrdquo in Proceedingsof the 2017 8th International Conference on Information andCommunication Systems (ICICS) pp 246ndash251 Irbid JordanApril 2017
[26] J Y Huo Z Zhang and C Tao ldquoUsing IPv6 address ad-vantage to build Network Node of Field observation In-struments in cold and arid areasrdquo China Education Networkno 5 pp 45-46 2018
[27] L Mateu and F Moll ldquoReview of energy harvesting tech-niques and applications for microelectronicsrdquo in Proceedingsof the International Society for Optical Engineering pp 359ndash373 Bellingham WA USA October 2005
[28] G Wang and R Y Wang ldquoRouting algorithm based oncluster-head optimization for self-energized wireless sensornetworkrdquo Journal of Computer Applications vol 38 no 334pp 201ndash216 2018
[29] X P Fan X Yang S Q Liu and Z H Qu ldquoClusteringrouting algorithm for wireless sensor networks with powerharvestingrdquo Computer Engineering vol 39 no 11 pp 126ndash134 2008
18 Journal of Electrical and Computer Engineering
[30] C H Zhang ldquoStudy on the energy heterogeneous clusteringrouting protocol for wireless sensor networksrdquo Science ampTechnology Vision no 13 pp 71+164ndash165 2012
[31] T Liu and F Li ldquoPower-efficient clustering routing protocolbased on applications in wireless sensor networkrdquo in Pro-ceedings of the International Conference on Wireless Com-munications IEEE Press Melbourne Australia September2009
Journal of Electrical and Computer Engineering 19
considers the node density residual energy distance fromthe BS and power consumption in selecting the CH At thesame time the non-CH selects the CH according to theresidual energy node density the power dissipated by theCH in the process of operation and the distance to the CHis protocol can increase the stable area of WSN balancethe load and ensure that all nodes similarly consume power
Some scholars have also proposed routing protocols forheterogeneous network structures Smaragdakis et al pro-posed a stable heterogeneous election protocol SEP [21] Inthe SEP protocol two kinds of nodes with different initialenergy are proposed which are the normal node with lessinitial energy and the advanced node with more initialenergy e advanced node is more likely to become a CHthan a normal node In general as the initial energy of thenetwork increases the overall lifetime of the network alsoincreases and the instability period decreases Howeverfactors such as energy and distance are not taken into ac-count in the CH election process so that the energy con-sumption of CH is not balanced
In the improved scheme of intercluster communicationHu and Xiao constructed intercluster multihop routing bycombining the idea of node chain in the PEGASIS protocol[22] Finally the node acting as a Leader on the chainundertakes the task of communication with the BS eprotocol reduces the energy consumed by direct commu-nication between multiple CHs and the BS in the LEACHprotocol At the same time the multihop transmissionbetween CHs also enhances the scalability of the network Liet al considered the ldquohot spotrdquo problem in multihop wirelesssensor networks [23]e hot spot problem refers to that theCH closer to the BS needs to bear more relay traffic thanother CHs leading to the premature death of the CH closerto the BS resulting in the exposure of the network area andpartitioning of network us the author divides the nodesinto clusters of different sizes e cluster radius increaseswith the distance between the CH and the BS In this way theCHs close to the BS bear less relay traffic which relativelybalances the network energy consumption and extends thenetwork life Furthermore in [24] the MHT-LEACHmethod proposed by Emad Alnawafa can determine whetherit is possible to transmit their data to BS through inter-mediate nodes according to its location and distance fromBS Compared with the LEACH protocol MHT-LEACHimproves network life stability and throughput enAlnawafa and Marghescu proposed the IMHT-LEACHmethod in [25] to solve the problem that MHT-LEACHrequires a large amount of energy to transfer data to the CHof the inner group IMHT-LEACH can reduce the energycost of data transfer to BS especially in the huge deploymentarea or the large distance from the sensor area to BSCompared with LEACH and MHT-LEACH protocolsIMHT-LEACH protocol can prolong the lifetime improvethe stability period and increase the throughput of thesensor network
ese protocols significantly reduce energy consump-tion in the data transmission phase but consume muchenergy in the process of establishing routing While ensuringhigh efficiency the efforts must be taken to avoid consuming
too much energy in establishing routes erefore we havemade the following contributions
(1) First of all we consider the factors such as energy inthe cluster head election stage and the clusteringstage solve the energy balance and ldquohot spotrdquoproblems and reduce the risk of premature death ofthe network
(2) en the regional autonomous intercluster multi-hop routing mechanism is adopted in the datatransmission phase to solve the problem of prema-ture death of nodes and achieve the purpose ofbalancing network energy consumption
(3) Finally simulation experiments are carried out onthe protocol and the results show that the networklifetime energy consumption rate stability andthroughput have been improved
3 FOI-LEACH Routing Protocol
Compared with WSNs the network of field observationinstruments is connected with data acquisition equipmentby network nodes Data acquisition instruments are gen-erally connected with several or dozens of sensor devices[26] which can observe a large number of observation el-ements It has the characteristics of large data storagecomplex network structure and so on e network hasrelatively few nodes which have strong processing capacityto process data and instructions to complete the commu-nication with the data acquisition equipment and othertasks ere is auxiliary power supply from solar cells fornetworking nodes but because the field observation in-strument networks are usually deployed in a harsh envi-ronment the problem of energy consumption must be fullyconsidered erefore we proposed an improved routingprotocol based on LEACH protocol to meet the needs of thefield observation instrument networking
31 Improvement in CH Election (reshold At the stage ofCH election the random election method of the originalLEACH protocol may let the nodes with less energy beselected as CHs leading to the premature death of net-working nodes To solve the energy consumption problem inthe harsh environment the energy factor of the node wasconsidered and the concept of ldquoself-energyrdquo was introducedto recharge the node With the continuous development andprogress of environmental energy collection technologyresearchers have been able to collect energy in the envi-ronment such as solar light mechanical vibration and heatand apply them to WSN [27] design sensors that can au-tomatically collect environmental energy e sensor nodecan convert the solar energy vibration energy and thermalenergy in the environment into usable electric energy andautomatically recharge energy for itself forming aWSNwiththe characteristics of self-energy [28] In order to achievelong-term observation and data transmission we adoptedthe solar cell power supply in the field observation instru-ment network so that the energy of network nodes can be
4 Journal of Electrical and Computer Engineering
recharged Correspondingly the election threshold of CHs ismodified to reduce the possibility that nodes with lowerenergy are elected as CHs
e threshold formula of node i in round r is shown asfollows
T(i)
popt
1 minus popt times mod r round 1popt1113872 11138731113872 1113873
timesEr(i) + Eh(i r minus 1)
Eo
i isin G
0 i notin G
⎧⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎨
⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎩
(2)
where popt is the optimal probability of a node becoming aCH Eo is the initial energy of the node Er(i) is the residualenergy of the current node and Eh(i r minus 1) is the energyobtained by the current node in the previous round Sincethe energy acquisition environment of each node is notconstant the energy acquisition rate of node i in k units oftime is denoted as αi(k) and the energy acquired by node iin the rminus 1 round [29] is denoted in the following equation
Eh(i r minus 1) 1113944
T(r)
kT(rminus1)
αi(k) (3)
According to the above analysis in the CH election theimproved threshold should consider the total number ofCHs needed by the network and the number of times eachnode has become a CH as well as the initial energy value ofthe node the residual energy value of the node in theprevious round and the supplied energy value of the nodeIn the process of cluster establishment of the r round eachnode firstly needs to count the initial energy value and thecurrent residual energy value and calculate the energy valueobtained in the previous round according to the energyrecharging status If the residual energy and recharge energyof the node are both low the probability of the node be-coming a CH in the r+ 1 round is reduced to avoid its deathdue to excessive energy consumption On the contrary whenthe residual energy and replenishment energy of the nodeare sufficient the probability of the node becoming a CH isincreased
32 Improvement in ClusteringMethod After the election ofthe CH the clustering operation is performed Since theLEACH protocol divides the network into clusters of equalsize the CHs near the BS not only have to bear the energyconsumed by the data transmission within their clusters butalso the forwarding energy brought by the CHs far awayfrom the BS which leads to unbalanced traffic load betweennodes and form a ldquohot spotrdquo problem In order to alleviateand avoid the ldquohot spotrdquo problem an energy-efficient andbalanced network clustering routing protocol for observa-tion instruments in harsh areas is constructed In the routingprotocol clusters of unequal sizes are constructed and thesize of the cluster is proportional to the distance between theCH and the BS In other words the closer it is to the BS the
smaller the cluster is and it consumes less energy in thecommunication within the cluster and more energy in theintercluster communication On the contrary the fartheraway from the BS the larger the cluster is and the more theenergy it consumes is concentrated in the communicationwithin the cluster Moreover since the node has differentenergy levels in the heterogeneous network not only thedistance between the node and the BS but also the currentresidual energy and recharge energy of the node should beconsidered to calculate the competitive radius [30] whichwas shown in the following equation
Rc 1 minus α timesdmax minus d(i BS)
dmax minus dminminus β times 1 minus
Er(i) + Eh(i r minus 1)
Eo
1113888 11138891113890 1113891 times R0c
(4)
in which α and β are the weighted factors of the value in [01] and satisfy the condition that α + β 1R0
c is the maxi-mum competitive radius dmax and dmin are the maximumand minimum values from nodes to BS in the networkd(i BS) is the distance between the current node i and theBS By dividing the network into clusters of different sizesaccording to the distance from the nodes to the BS thecurrent residual energy and the supply energy of the nodesthe CHs near or far away the BS consume approximatelyequal energy so as to achieve the purpose of energy balancein the field instrument network
33 Improvement in Communication Method After theelection of CHs and the formation of clusters the networkenters the stable transmission stage In general the time ofstable transmission is longer than that of cluster formationIn the LEACH protocol data transmission is a single-hoptransmission at is all member nodes send the collecteddata information to the CH of the cluster and the CH sendsit to the BS after data fusion is causes the CH far awayfrom the BS to consumemore energy so that it may die in thetransmission process and fail to transmit data successfullywhich significantly reduces the network efficiency ere-fore a multihop approach to data transmission was con-sidered and the concept of ldquozonerdquo was introduced in thispaper e zone especially refers to the ring bands formed bytaking the BS as the center of the circle and the adjacentcircumferential lines with different lengths as the radius Azone can contain several clusters and a cluster must belongto a specific zone [8] e BS controls the transmissionenergy broadcasts the information of different intensitiesand divides the monitoring area into three-ring zones A Band C as shown in Figure 2 e data communicationmethod adopts the principle of nearest partitioning that isthe CH in zone C selects the CH closest to it in zone B as thenext hop Similarly the CH in zone B selects the nearest CHin zone A as the next hop e CH in zone A communicatesdirectly with the BS According to the characteristics ofpartitioning because cluster nodes in zone A and zone Bneed to bear more energy consumed by data fusion andforwarding only the nodes in zone A and zone B arepowered by solar cells
Journal of Electrical and Computer Engineering 5
34 Analysis of Heterogeneity In this paper in order toprolong the stable stage of the network we adopted the valueof heterogeneity set in literature [21] to set up two kinds ofnodes with different initial energies namely the normalnodes with lower initial energy and the advanced nodes withhigher initial energy Advanced nodes are more likely tobecome CHs and not easy to die than normal nodes which isto balance energy consumption At the same time the totalenergy of the network has changed If the initial energy of thenormal node is Eo the initial energy of the advanced node is(1 + a) middot Eo So the total energy of the network is changed to(1 minus m) middot Eo + m middot (1 + a) middot Eo (1 + a middot m) middot Eo that is thetotal energy of the network has increased by 1 + am timesAccordingly in the CH election the optimal probability ofthe node becoming the CH has also been changed e
weighted probabilities of normal nodes and advanced nodesare shown in the following equations respectively
pnrm popt
1 + α middot m (5)
padv popt
1 + αmtimes(1 + a) (6)
e optimal CH number is kopt n2π
radicmiddot
EfsEmp
1113969middot
md2toBS [30] where kopt represents the optimal cluster
number n is the number of nodes set in the monitoring areaMtimesM and dtoBS represents the distance between the CHand the BS
For normal nodes the modified election threshold isshown in equation (7) Similarly the election threshold foradvanced nodes is shown in equation (8)
T(i)
pnrm
1 minus pnrm times mod r round 1pnrm( 1113857( 1113857times
Er(i) + Eh(i r minus 1)
Eo
i isin G
0 i notin G
⎧⎪⎪⎪⎪⎨
⎪⎪⎪⎪⎩
(7)
T(i)
padv
1 minus padv times mod r round 1padv( 1113857( 1113857times
Er(i) + Eh(i r minus 1)
Eo
i isin G
0 i notin G
⎧⎪⎪⎨
⎪⎪⎩(8)
In the above two threshold equations it can be foundthat the weighted probabilities are different because theadvanced node has more initial energy Due to the energyfactor is taken into account when electing the CH the higherthe energy is the easier it is to become the CH so theadvanced nodes are more likely to become the CHs than thenormal nodes
35 FOI-LEACH Routing Protocol FOI-LEACH protocolintroduces the concepts of ldquoself-energizedrdquo and ldquozonerdquocombined with the characteristics of field instrument net-working In addition the CH election stage and cluster
formation stage are carried out in each zone respectivelye flow of each round of the FOI-LEACH protocol isshown in Figure 3 and the specific operation steps aredescribed as follows
(1) After the deployment of the network nodes eachnode estimates the distance from the BS according tothe signal strength transmitted by the BS judges andidentifies the zone to which it belongs
(2) At the beginning of the CH election the nodegenerates a random number from 0 to 1 counts thecurrent residual energy Er(i) and the previous roundof energy replenishment Eh(i r minus 1) and determines
ABC
Figure 2 Partitioning method in the routing protocol
6 Journal of Electrical and Computer Engineering
whether the node is an advanced node Moreover ifit is an advanced node it calculates the threshold asshown in equation (8) otherwise it calculates thethreshold as shown in equation (7) and then judgeswhether the random number generated by the nodeis lower than the threshold if so announce themessage that it becomes the CH otherwise it be-comes a member node and waits for the schedulingof the CH
(3) After the CH election according to the BS radiomessage all the nodes maximum distance dmax andminimum dmin of network nodes to the BS and thedistance d(i BS) of the current node to the BS arestatistically counted and the current residual energy ofthe node Er(i) and the energy supply of the previousround Eh(i r minus 1) are calculated and then clustercompetition radii are computed e node detects thereceived announcement message and determineswhether the CH exists within the competition radiusof the zone If so a CH is selected according to thecompetition radius to join and form a cluster If thereis no CH within the competitive radius it automat-ically becomes a CH and publishes a notice
(4) After the cluster is formed the CH creates a TDMAschedule and the member nodes in the cluster waitfor the CH to be scheduled
(5) In the data transmission stage cluster member nodescollect data regularly and send the data directly to theCH through the single-hop transmission e CHcompresses and fuses the received data and thensends it to the nearest CH in the next zone until it istransmitted to the BS Loop through steps 1 to 5 untilthe network fails
4 Network Model of FieldObservation Instruments
41 Network Model In this paper we consider the randomdeployment of n nodes in a square monitoring area with asize of MtimesM e assumptions for the networking envi-ronment are as follows
All networking nodes have unique IDs and areheterogeneousAll networking nodes are randomly deployed in themonitoring area and cannot be moved afterdeploymentAll networking nodes know their residual energy andsome nodes can supplement the energyAll networking nodes can determine the distance fromthe information source according to the intensity of thereceived information
Start
Base station broadcastscluster head election
Node i generatesrandom number t (01)
Is it an advancednode
Becomes the ordinary node and waits for the cluster head node
to broadcast information
Yes
Request to join the nearest cluster
Enter the data transfer phasepartition autonomous multihop
mechanism
Waiting for the scheduling of the cluster head
Cluster headselection
The formationof the cluster
Create aschedule
Datatransmission
After a period oftime
NotltT(n)nrm tltT(n)advYes
Becomes the clusterhead nodes and
broadcasts the message
Waiting for theordinary node to
request to join
Create the TDMAschedule table
Yes
No No
The node performsself-energizing
End
Becomes the clusterhead node and
broadcasts the message
Waiting for theordinary node to
request to join
Create the TDMAschedule table
Figure 3 Flow chart of operation in each round of FOI-LEACH protocol
Journal of Electrical and Computer Engineering 7
e BS is located outside the monitoring area it hassufficient energy resources and each node knows thelocation of the BS
42 Energy Model Energy consumption is an importantcriterion to evaluate the performance of a routing protocole network life mainly depends on the energy consumed indata sending and data receiving Meanwhile the energyconsumed by the CH when using the fusion technologyshould be considered and the energy consumption of thenode in the process of calculation and storage should beneglected LEACH protocol uses first-order wireless mode inWSNs so it adopts a simple energy consumptionmodel [12]e model defines that the energy consumed by each l bitdata sent by the wireless circuit is
ETx(l d) ETxminuselec(l d) + ETxminusamp(l d)
lEelec + lEfsd
2 dlt d0
lEelec + lEmpd4 dge d0
⎧⎨
⎩
(9)
When receiving information the energy consumed bythe wireless circuit receiving l bit data is
ERx(l d) ERxminuselec(l d) lEelec (10)
e energy consumed by data fusion is
EGx lEgather (11)
In equations (9)-(10) d represents the distance betweenthe sending node and the receiving node and Eelec representsthe energy consumed for each bit of data sent or received Inequation (9) Efsd
2 is the energy consumed by the free spacemodel for each l bit of data amplification and Empd4 is theenergy consumed by the multipath attenuation model foreach l bit of data amplification Obviously when the distancebetween nodes becomes more extensive the energy con-sumption increases exponentially erefore if you want toreduce the energy consumption of data transmission youmust reduce the distance between nodes e Egather inequation (11) is expressed as the energy consumed by datafusion for each processing of 1 bit the d0 in equation (9) is athreshold which is determined by the equation (12) and isdefined as 87m in this paper
d0
Efs
Emp
1113971
(12)
5 Simulation Experiments and Analysis
51 Experimental Setting In order to analyze the perfor-mance of the FOI-LEACH protocol this paper conductssimulation experiments onMATLAB simulation platform tocompare it with the original LEACH protocol [4] SEPprotocol [21] and PECRP protocol [31] e simulationexperiments were carried out under the monitoring area of100mtimes 100m and the BS is located outside the monitoringarea with the coordinate of (150 50) As shown in Figure 4
the initial node distribution map distinguishes the nodes ineach zone by color in which red represents the nodes in zoneA blue represents the nodes in zone B and the greenrepresents the nodes in zone C And ldquordquo means the normalnode ldquo+rdquo means the advanced node and ldquotimesrdquo means BS
In the self-energy experiment all the surviving nodes inthe network are replenished with energy once every fiverounds until the simulation end e recharge energy isdistributed randomly to all remaining surviving nodes in thenetwork e total energy of the first replenishment is set to035 J In the later replenishment in order to prevent thenodes in the network from dying when there are too fewnodes We set the attenuation factor alpha to 09 that is theenergy replenishment to all the nodes in the network is 09times of the previous timee initial energy and topology ofall the experimental networks were set to the same envi-ronment When all the nodes in the network die the net-work is considered to be invalid Experiments proved thatthe network works best when the parameters are set to thefollowing valuesm is set to 01 a is set to 2 α is set to 03 andβ is set to 07e range of optimal CH number is [1 14] and10 is taken in this paper the probability of optimal CHnumber is popt 0 1 e three-partition system shown inFigure 2 was adopted in the routing protocol e specificparameters of the simulation experiments are listed inTable 1
52 Determination of the Partitioning Scheme e FOI-LEACH protocol proposed in this paper is based on theimprovement of the LEACH protocol In the initial stage ofnode deployment the distance between the node and the BSis obtained according to the signal strength of the BS re-ceived by the node en the monitoring area is partitionedaccording to the distance To determine the optimal parti-tioning scheme in the FOI-LEACH protocol we proposedthe following five schemes for the protocol and tested themin the partitioning experiment
Scheme 1 e monitoring area is divided into twozones A and B and the zone SA of A is equal to thezone SB of B as shown in Figure 5 (partitioning scheme1) e CH in zone B chooses the CH in zone A closest
0 50 100 1500
10
20
30
40
50
60
70
80
90
100
Advanced node
Normal node
BS
Figure 4 Distribution diagram of initial nodes
8 Journal of Electrical and Computer Engineering
to it for forwarding data and the CHs in zone Acommunicates directly with the BSScheme 2 As shown in Figure 5 (partitioning scheme2) the monitoring area is divided into two zones A andB and the SA of zone A is smaller than the area SB ofzone BScheme 3 e monitoring area is divided into threezones A B and C and the area SA of zone A is equalto the area SB of zone B and smaller than the area SC
of zone C as shown in Figure 5 (partitioning scheme3)Scheme 4 e monitoring area is divided into threezones A B and C and the area SA of zone A is smallerthan the area SB of zone B and smaller than the area SC
of zone C as shown in Figure 5 (partitioning scheme 4)Scheme 5 e monitoring area is divided into threezones A B and C and the area SA of zone A is equal tothe area SC of zone C and smaller than the area SB ofzone B as shown in Figure 5 (partitioning scheme 5)
e survival nodes and the average residual energy ineach round of the five partitioning schemes are drawn inFigures 6 and 7 respectively Based on the experimentalanalysis it can be found that Scheme 3 indicated as a redcurve in the figures has a better performance In scheme 3ie SA SB lt SC the first dead node appears in the 587thround which is later than other schemes that is thestability period is more extended than other schemes eaverage residual energy consumption rate of nodes is alsolower than that of other schemes is is because zones Aand B need to bear more forwarding energy so when thesetwo zones are smaller than zone C the network energyconsumption is more balanced erefore we adopted thepartitioning method of scheme 3 to carry out the simu-lation experiments
53 Analysis of Parameters In equation (4) parameters αand β determine the difference in cluster size erefore therelationship between these two parameters and network lifewas observed by taking α from 0 to 1 and β from 1 to 0 eresults of parameters analysis are shown in Figure 8 whichalso proves the rationality of our unequal clusteringmechanism When parameter α increases from 0 to 1 theeffect of the unequal clustering method is noticeableHowever the impact of parameter β on the network shouldalso be considered If the value of α is too large the lifetimeof the system will be shortened It is because too manyclusters will be generated near the BS and each cluster sendspackets to the BS which results in the waste of energyerefore it needs to determine the optimal values forparameters α and β In this experiment we can concludefrom Figure 8 that when α 0 3 and β 0 7 the death timeof the first node is later and the network is more stable
54 Experimental Comparison Analysis is paper mainlyevaluates the performance of the observation instrumentnetwork routing protocol with and without energy supplythrough the following evaluation elements
Network lifetime the network lifetime is measured bythe survival rate of the whole network nodes whichgenerally represents a certain proportion of the energyloss of the network node In this paper we took thedeath time interval from the beginning of the networkto the last surviving node as the lifetime of the networkEnergy consumption rate it usually refers to the av-erage energy consumption of a node sending or re-ceiving a byte of data It is essential to evaluate theperformance of routing algorithmsStability the stability of the field instruments obser-vation network was evaluated from two aspects thetime interval from the beginning of the network to thedeath of the first node and the number of CHsNetwork throughput the indicator to measure theefficiency of the network which is usually judged by thetotal number of packets sent to BS and the total numberof packets sent to CH
541 Experiments without Energy Supply
(1) Network Lifetime Figure 9 shows the number of sur-viving nodes in the network when the network runs for 2100rounds without being self-energized According to thestatistics of the number of rounds of death node in Table 2the network failure of the LEACH protocol occurs at round276 the network of SEP protocol expires at 462 rounds andnetwork failure of the PECRP protocol at round 438However the FOI-LEACH protocol was not expired untilround 2042 which significantly increased the networksurvival time It is because the FOI-LEACH protocol con-siders such factors as energy and distance in stages of CHelection cluster formation and intercluster communication
Table 1 Parameters in the simulation experiments
Parameter ValueTotal number of nodes N 100Network area (m) 100times100Coordinates of BS (m) (150 50)Data packet size L (bit) 4000Initial energy of normal node (J) 01Initial energy of advanced node (J) 03Energy consumption of transmitting circuit ETX (nJbit) 50
Energy consumption of receiving circuit ERX (nJbit) 50Free space model energy Efs (pJbitm
2) 10Multipath attenuation model energy Emp (pJbitm2) 00013Energy consumption of data fusion EDA (nJbit) 5Probability of the optimal number of CHs popt 01Maximum cluster radius in zone A RcA (m) 125Maximum cluster radius in zone B RcB (m) 125Maximum cluster radius in zone C RcC (m) 25Attenuation factor alpha 09M 01A 2α 03β 07
Journal of Electrical and Computer Engineering 9
AB
(a)
AB
(b)
ABC
(c)
ABC
(d)
ABC
(e)
Figure 5 Partitioning scheme (a) Partitioning scheme 1 SaltSb (b) Partitioning scheme 2 SaSb (c) Partitioning scheme 1 SaSbltSc (d)Partitioning scheme 1 SaltSbltSc (e) Partitioning scheme 1 SaScltSb
AeqBAsBAeqBsC
AsBsCAeqCsB
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
Figure 6 Comparison of active nodes in each round
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
002
004
006
008
01
012
Ave
rage
resid
ual e
nerg
y
AeqBAsBAeqBsC
AsBsCAeqCsB
Figure 7 Comparison of average residual energy in each round
10 Journal of Electrical and Computer Engineering
(2) Average Residual Energy and Energy Dissipation RateFigure 10 shows the graph of the average residual energy ofthe network running 2100 rounds without being self-en-ergized Combined with the network average residual en-ergy which is shown in Table 3 it can be drawn that the FOI-LEACH protocol is more slowly energy consumed Besidesit can be seen from Figure 10 that the energy consumption
rate of the improved network is significantly reduced toachieve the purpose of delaying energy consumption andextending network life
(3) Stability e stability of networking was evaluated fromtwo aspects First it can be seen from Figure 9 that the FOI-LEACH protocol significantly extends the death time of the
Self-energized
400
420
440
460
480
500
520
540
Dea
th ti
me o
f the
firs
t nod
e
01 02 03 04 05 06 07 08 09 10α
Figure 8 Impact of parameters α and β on the network lifetime
LEACHSEP
PECRPImproved protocol
400
160060
0
2000
1000
1200
140020
0
1800
21000
800
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
Figure 9 Comparison of live nodes in each round without power supply
Table 2 Statistics number of rounds of dead nodes of the four protocols without power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 135 160 204 276SEP 174 191 226 462PECRP 338 374 412 438FOI-LEACH 481 684 1272 2042
Journal of Electrical and Computer Engineering 11
first node For the LEACH protocol the nodes began to dieat round 135 SEP protocol at round 174 and PECRPprotocol at round 338 Because the energy factor is takeninto account in selecting the CH energy and distance factorsare taken into account in clustering and the adopted zone-based autonomous multihop communication model mini-mizes the Hello control package the nodes die at round 481for the FOI-LEACH protocol As a result the FOI-LEACHprotocol has better performance than other protocols
Figure 11 shows the distribution of the number ofclusters of the four protocols without energy supply simulatedfor 10 rounds of random elections in which Figure 11(a)represents the statistics number of CHs in each zone of theFOI-LEACH protocol and Figure 11(b) represents the sta-tistics number of CHs in the whole network of FOI-LEACHprotocol Figures 11(c)ndash11(e) represent the statistics numberof CHs of LEACH SEP and PECRP protocols respectively Itcan be seen that the number of CHs of FOI-LEACH protocolis more stable than that of LEACH SEP and PECRP BecauseLEACH and SEP randomly select CHs the number of CHsproduced was unstable e FOI-LEACH protocol formsclusters by selecting CHs with a competitive radius and thenumber of CHs is relatively stable
(4) Network (roughput Figure 12 shows that in theLEACH protocol SEP protocol PECRP protocol and ourproposed FOI-LEACH protocol the total number of packets
sent to BS is approximately 900 2580 2980 and 11140respectively Moreover Figure 13 shows that in the LEACHprotocol SEP protocol PECRP protocol and FOI-LEACHprotocol the total number of packages sent to CHs is ap-proximately 7500 21000 38200 and 119000 respectively Itis because the proposed scheme has a high network lifetimethe total number of packets sent to BS and CHs is muchhigher than other protocols
542 Experiments with Energy Supply
(1) Network Lifetime Figure 14 shows the number of sur-viving nodes in the network when the network runs for 2300rounds self-energized According to the statistics of deathnodes in Table 4 we can find that the network lifetime of thefour protocols all has been extended e network failure ofthe LEACH protocol occurred at round 341 the network ofthe SEP protocol expires at round 665 and network failure ofPECRP protocol at round 530 and the FOI-LEACH pro-tocol was not expired until round 2246 which significantlyincreased the network survival time It is demonstrated thatthe improved schemes can work well in both the environ-ments with or without power supply
(2) Average Residual Energy and Energy Dissipation RateFigure 15 shows the graph of the average residual energy ofthe network running 2300 rounds self-energized Combinedwith the network average residual energy which shown inTable 5 it can be drawn that the FOI-LEACH protocol ismore slowly energy consumed Besides it can be seen fromFigure 15 that the energy consumption rate of the improvednetwork is significantly reduced to achieve the purpose ofdelaying energy consumption and extending network life
(3) Stability For the stability of field instruments net-working it can be seen from Figure 14 that the FOI-LEACHprotocol significantly extends the death time of the first
1800
2000
1000
1600
210060
0
200
8000
120040
0
1400
Number of rounds
0
002
004
006
008
01
012
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 10 Comparison of average residual energy in each round without power supply
Table 3 Statistics of the average residual energy (J) of nodes of thefour protocols without power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0075 0007 0 0SEP 0094 002 0 0PECRP 0088 0053 0 0FOI-LEACH 0113 0092 0043 152times10minus5
12 Journal of Electrical and Computer Engineering
ABC
0
1
2
3
4
5
6
7Co
mpa
rison
of C
Hs i
n ea
ch re
gion
2 3 4 5 6 7 8 9 101Number of rounds
(a)
0
2
4
6
8
10
12
14
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(d)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 11 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol without power supply
Journal of Electrical and Computer Engineering 13
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
2000
4000
6000
8000
10000
12000
Pack
ets t
o BS
LEACHSEP
PECRPImproved protocol
Figure 12 Comparison of packets sent to BS from CHs without power supply
times104
200
400
600
800
1000
1200
2000
1800
21000
1400
1600
Number of rounds
0
2
4
6
8
10
12
Pack
ets t
o CH
LEACHSEP
PECRPImproved protocol
Figure 13 Comparison of packets sent to CHs from member nodes without power supply
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
LEACHSEP
PECRPImproved protocol
Figure 14 Comparison of live nodes in each round with power supply
14 Journal of Electrical and Computer Engineering
Table 4 Statistics number of rounds of dead nodes of the four protocols with power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 177 204 232 341SEP 185 210 264 665PECRP 392 430 493 530FOI-LEACH 555 716 1238 2246
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
002
004
006
008
01
012
014
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 15 Comparison of average residual energy in each round with power supply
Table 5 Statistics of the average residual energy (J) of nodes of the four protocols with power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0086 0018 0 0SEP 0105 0036 0001 0PECRP 0099 007 0 0FOI-LEACH 0124 0109 0062 0001
0
1
2
3
4
5
6
7
8
Com
paris
on o
f CH
s in
each
regi
on
2 3 4 5 6 7 8 9 101Number of rounds
ABC
(a)
0
2
4
6
8
10
12
1415
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
Figure 16 Continued
Journal of Electrical and Computer Engineering 15
0
2
4
6
8
10
12
14
16N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14
16
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(d)
0
2
4
6
8
10
12
14
16
18
20
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 16 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol with power supply
0
2000
4000
6000
8000
10000
12000
14000
Pack
ets t
o BS
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 17 Comparison of packets sent to BS from CHs with power supply
16 Journal of Electrical and Computer Engineering
node e supplied energy promotes the extension of thenetwork lifetime and the stability of the networking for thefour protocols in varying degrees For the LEACH protocolthe node began to die at round 177 SEP protocol at round185 PECRP protocol at round 392 and round 555 for theimproved FOI-LEACH protocol
e distributions of the number of clusters in the fourprotocols with energy supply simulated for 10 rounds ofrandom elections are shown in Figure 16 Like the previousfigures Figure 16(a) represents the statistics number of CHsof each zone of FOI-LEACH protocol Figures 16(b)ndash16(e)represent the statistics number of CHs of FOI-LEACHprotocol LEACH protocol SEP protocol and PECRPprotocol respectively Due to the efficient schemes of CHselecting and clustering the FOI-LEACH protocol showssignificantly better performance than the other threeprotocols
(4) Network (roughput In the environment of self-energyas shown in Figure 17 the total number of packets sent toBS of the LEACH protocol SEP protocol PECRP protocoland the proposed FOI-LEACH protocol is approximately2428 3080 3746 and 13265 respectively Moreover inFigure 18 the total number of packages sent to CHs of theLEACH protocol SEP protocol PECRP protocol andFOI-LEACH protocol is approximately 21400 2430044000 and 123200 respectively We can find that the totalnumber of packets sent by our protocol to BS and CHs ismuch higher than the other protocols which also dem-onstrated that the proposed protocol has a better networkthroughout
6 Conclusions
According to the characteristics of field observation in-strument networking an improved protocol FOI-LEACHbased on LEACH protocol was proposed in this paper Byconsidering the energy factor in the CH election threshold
and referring to the SEP protocol to set up two kinds ofnodes with different initial energies which are calledadvanced nodes and normal nodes the network model offield observation instruments has been established Inaddition to solve the problem that the LEACH protocolconsumes much energy during transmission and results inuneven energy consumption for the direct and long-distance transmission the improved protocol adopted the3 zones of partitioning mechanism and the multihoptransmission mechanism to alleviate and avoid the ldquohotspotrdquo problems Furthermore energy supplies were addedto the nodes in A and B zones that are responsible formore energy transmission so as to balance the energyconsumption of the network and prolong the networklifetime In the simulation experiments we compared theperformance of the FOI-LEACH protocol with theLEACH SEP and PECRP protocols in two cases with orwithout energy supply Comparing performance indica-tors of network lifetime energy consumption rate sta-bility and network throughput the proposed FOI-LEACH protocol can slow down the death of nodes andthe energy consumption rate obviously and shows asignificantly better performance than other three proto-cols e experimental results demonstrated that the FOI-LEACH protocol could balance network energy con-sumption and alleviate the ldquohot spotrdquo problem to extendthe lifetime of network nodes in the field observationinstruments network e future work is to implementand port the improved protocol to the hardware of net-working node we designed and developed previously andtest and verify the feasibility and stability of the protocolin the actual situation
Data Availability
e initial nodes are generated randomly in the networkand there are no observation data used in the simulationexperiments
0
20000
40000
60000
80000
100000
120000
140000
Pack
ets t
o CH
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 18 Comparison of packets sent to CHs from nodes with power supply
Journal of Electrical and Computer Engineering 17
Conflicts of Interest
e authors declare that there are no conflicts of interest
Acknowledgments
is work was supported by the National Nature ScienceFoundation of China (Grant no 61862038) the LanzhouTalent Innovation and Entrepreneurship Technology PlanProject (no 2019-RC-14) and the Foundation of a HundredYouth Talents Training Program of Lanzhou JiaotongUniversity
References
[1] J Y Huo Z N Ren and Y R Yang A Kind of InstrumentNetwork Node Equipment and Monitoring System ChinesePatents Beijing China 2017
[2] J Y Huo Key Technology and Application Research ofE-Science Virtual Joint Observation System for Geoscience inCold and Dry Regions University of Chinese Academy ofSciences Beijing China 2012
[3] I F Akyildiz W L Weilian Su Y Sankarasubramaniam andE Cayirci ldquoA survey on sensor networksrdquo IEEE Communi-cations Magazine vol 40 no 8 pp 102ndash114 2002
[4] W R Heinzelman A Chandrakasan and H BalakrishnanldquoEnergy-efficient communication protocol for wirelessmicrosensor networksrdquo in Proceedings of the 33rd HawaiiIntentional Conference on System Sciences Maui HI USAJanuary 2000
[5] D Mehta and S Saxena ldquoA comparative analysis of energyefficient hierarchical routing protocols for wireless sensornetworksrdquo in Proceedings of the 2018 4th InternationalConference on Computing Sciences (ICCS) pp 53ndash58Jalandhar India August 2018
[6] C Karlof and D Wagner ldquoSecure routing in wireless sensornetworks attacks and countermeasuresrdquo Ad Hoc Networksvol 1 2003
[7] L B Oliveira A Ferreira M A Vilaca et al ldquoSecLEACH-onthe security of clustered sensor networksrdquo Signal Processingvol 87 2007
[8] Y Y Gu GW Bai and J J Tao ldquoAZM-LEACH autonomouszone-based multi-hop routing protocol in WSNsrdquo ComputerEngineering and Applications vol 47 no 20 pp 58ndash61 2011
[9] L XWang Research on Routing Technology ofWireless SensorNetworks Based on Data Aggregation Shenyang LigongUniversity Shenyang China 2015
[10] J P Shao Research on Key Energy-Efficient Routing Tech-nology of WSN Based on Cluster Shenyang Ligong UniversityShenyang China 2015
[11] V K Arora V Sharma and M Sachdeva ldquoA survey onLEACH and otherrsquos routing protocols in wireless sensornetworkrdquo Optik vol 127 no 16 pp 6590ndash6600 2016
[12] W B Heinzelman A P Chandrakasan and H BalakrishnanldquoAn application-specific protocol architecture for wirelessmicrosensor networksrdquo IEEE Transactions on WirelessCommunications vol 1 no 4 pp 660ndash670 2002
[13] S Al-Sodairi and R Ouni ldquoReliable and energy-efficientmulti-hop LEACH-based clustering protocol for wirelesssensor networksrdquo Sustainable Computing Informatics andSystems vol 20 pp 1ndash13 2018
[14] O Younis and S Fahmy ldquoHEED a hybrid energy-efficientdistributed clustering approach for ad hoc sensor networksrdquo
IEEE Transactions on Mobile Computing vol 3 no 4pp 366ndash379 2004
[15] B B Chen and Y L Shi ldquoWSN routing protocol based oncluster heads selection in regionsrdquo Computer Engineeringvol 37 no 19 pp 96ndash98 2011
[16] P Azada ldquoCluster head selection in wireless sensor networksunder fuzzy environmentrdquo ISRN Sensor Networks vol 2013Article ID 909086 8 pages 2013
[17] S Soro and W B Heinzelman ldquoCluster head election tech-niques for coverage preservation in wireless sensor networksrdquoAd Hoc Networks vol 7 no 5 pp 955ndash972 2009
[18] A akkar ldquoDEAL distance and energy based advancedleach protocolrdquo in Proceedings of the International Conferenceon Information and Communication Technology for IntelligentSystems pp 370ndash376 Ahmedabad India March 2017
[19] T Y Chang W N Liu Y Zhang and H Y Li ldquoOptimizedLEACH protocol based on distance and energy of clusterheadrdquo Journal of Hebei University (Natural Science Edition)vol 39 no 2 pp 194ndash200 2019
[20] P Mehra M Doja and B Alam ldquoStability enhancement inLEACH (SE-LEACH) for homogeneousWSNrdquo EAI EndorsedTransactions on Scalable Information Systems vol 6 no 20pp 1ndash9 2019
[21] G Smaragdakis I Matta and A Bestavros ldquoSEP a stableelection protocol for clustered heterogeneous wireless sensornetworksrdquo in Proceedings of the Second InternationalWorkshop on Sensor and Actor Network Protocols and Ap-plications (SANPA 2004) pp 1ndash11 Boston MA USA June2004
[22] F S Hu and Q Xiao ldquoMulti-hop routing algorithm of energy-balancing based on LEACHrdquo Journal of Chinese ComputerSystems vol 35 no 1 pp 72ndash75 2014
[23] C F Li M Ye G H Chen and J Wu ldquoAn energy-efficientunequal clustering mechanism for wireless sensor networksrdquoin Proceedings of the IEEE International Conference on MobileAdhoc and Sensor Systems Conference p 604 WashingtonDC USA November 2005
[24] E Alnawafa I Marghescu and MHT ldquoMulti-hop techniquefor the improvement of leach protocolrdquo in Proceedings of the2016 15th RoEduNet Conference Networking in Education andResearch pp 1ndash5 Bucharest Romania September 2016
[25] E Alnawafa and I Marghescu ldquoIMHT improved MHT-LEACH protocol for wireless sensor networksrdquo in Proceedingsof the 2017 8th International Conference on Information andCommunication Systems (ICICS) pp 246ndash251 Irbid JordanApril 2017
[26] J Y Huo Z Zhang and C Tao ldquoUsing IPv6 address ad-vantage to build Network Node of Field observation In-struments in cold and arid areasrdquo China Education Networkno 5 pp 45-46 2018
[27] L Mateu and F Moll ldquoReview of energy harvesting tech-niques and applications for microelectronicsrdquo in Proceedingsof the International Society for Optical Engineering pp 359ndash373 Bellingham WA USA October 2005
[28] G Wang and R Y Wang ldquoRouting algorithm based oncluster-head optimization for self-energized wireless sensornetworkrdquo Journal of Computer Applications vol 38 no 334pp 201ndash216 2018
[29] X P Fan X Yang S Q Liu and Z H Qu ldquoClusteringrouting algorithm for wireless sensor networks with powerharvestingrdquo Computer Engineering vol 39 no 11 pp 126ndash134 2008
18 Journal of Electrical and Computer Engineering
[30] C H Zhang ldquoStudy on the energy heterogeneous clusteringrouting protocol for wireless sensor networksrdquo Science ampTechnology Vision no 13 pp 71+164ndash165 2012
[31] T Liu and F Li ldquoPower-efficient clustering routing protocolbased on applications in wireless sensor networkrdquo in Pro-ceedings of the International Conference on Wireless Com-munications IEEE Press Melbourne Australia September2009
Journal of Electrical and Computer Engineering 19
recharged Correspondingly the election threshold of CHs ismodified to reduce the possibility that nodes with lowerenergy are elected as CHs
e threshold formula of node i in round r is shown asfollows
T(i)
popt
1 minus popt times mod r round 1popt1113872 11138731113872 1113873
timesEr(i) + Eh(i r minus 1)
Eo
i isin G
0 i notin G
⎧⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎨
⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎩
(2)
where popt is the optimal probability of a node becoming aCH Eo is the initial energy of the node Er(i) is the residualenergy of the current node and Eh(i r minus 1) is the energyobtained by the current node in the previous round Sincethe energy acquisition environment of each node is notconstant the energy acquisition rate of node i in k units oftime is denoted as αi(k) and the energy acquired by node iin the rminus 1 round [29] is denoted in the following equation
Eh(i r minus 1) 1113944
T(r)
kT(rminus1)
αi(k) (3)
According to the above analysis in the CH election theimproved threshold should consider the total number ofCHs needed by the network and the number of times eachnode has become a CH as well as the initial energy value ofthe node the residual energy value of the node in theprevious round and the supplied energy value of the nodeIn the process of cluster establishment of the r round eachnode firstly needs to count the initial energy value and thecurrent residual energy value and calculate the energy valueobtained in the previous round according to the energyrecharging status If the residual energy and recharge energyof the node are both low the probability of the node be-coming a CH in the r+ 1 round is reduced to avoid its deathdue to excessive energy consumption On the contrary whenthe residual energy and replenishment energy of the nodeare sufficient the probability of the node becoming a CH isincreased
32 Improvement in ClusteringMethod After the election ofthe CH the clustering operation is performed Since theLEACH protocol divides the network into clusters of equalsize the CHs near the BS not only have to bear the energyconsumed by the data transmission within their clusters butalso the forwarding energy brought by the CHs far awayfrom the BS which leads to unbalanced traffic load betweennodes and form a ldquohot spotrdquo problem In order to alleviateand avoid the ldquohot spotrdquo problem an energy-efficient andbalanced network clustering routing protocol for observa-tion instruments in harsh areas is constructed In the routingprotocol clusters of unequal sizes are constructed and thesize of the cluster is proportional to the distance between theCH and the BS In other words the closer it is to the BS the
smaller the cluster is and it consumes less energy in thecommunication within the cluster and more energy in theintercluster communication On the contrary the fartheraway from the BS the larger the cluster is and the more theenergy it consumes is concentrated in the communicationwithin the cluster Moreover since the node has differentenergy levels in the heterogeneous network not only thedistance between the node and the BS but also the currentresidual energy and recharge energy of the node should beconsidered to calculate the competitive radius [30] whichwas shown in the following equation
Rc 1 minus α timesdmax minus d(i BS)
dmax minus dminminus β times 1 minus
Er(i) + Eh(i r minus 1)
Eo
1113888 11138891113890 1113891 times R0c
(4)
in which α and β are the weighted factors of the value in [01] and satisfy the condition that α + β 1R0
c is the maxi-mum competitive radius dmax and dmin are the maximumand minimum values from nodes to BS in the networkd(i BS) is the distance between the current node i and theBS By dividing the network into clusters of different sizesaccording to the distance from the nodes to the BS thecurrent residual energy and the supply energy of the nodesthe CHs near or far away the BS consume approximatelyequal energy so as to achieve the purpose of energy balancein the field instrument network
33 Improvement in Communication Method After theelection of CHs and the formation of clusters the networkenters the stable transmission stage In general the time ofstable transmission is longer than that of cluster formationIn the LEACH protocol data transmission is a single-hoptransmission at is all member nodes send the collecteddata information to the CH of the cluster and the CH sendsit to the BS after data fusion is causes the CH far awayfrom the BS to consumemore energy so that it may die in thetransmission process and fail to transmit data successfullywhich significantly reduces the network efficiency ere-fore a multihop approach to data transmission was con-sidered and the concept of ldquozonerdquo was introduced in thispaper e zone especially refers to the ring bands formed bytaking the BS as the center of the circle and the adjacentcircumferential lines with different lengths as the radius Azone can contain several clusters and a cluster must belongto a specific zone [8] e BS controls the transmissionenergy broadcasts the information of different intensitiesand divides the monitoring area into three-ring zones A Band C as shown in Figure 2 e data communicationmethod adopts the principle of nearest partitioning that isthe CH in zone C selects the CH closest to it in zone B as thenext hop Similarly the CH in zone B selects the nearest CHin zone A as the next hop e CH in zone A communicatesdirectly with the BS According to the characteristics ofpartitioning because cluster nodes in zone A and zone Bneed to bear more energy consumed by data fusion andforwarding only the nodes in zone A and zone B arepowered by solar cells
Journal of Electrical and Computer Engineering 5
34 Analysis of Heterogeneity In this paper in order toprolong the stable stage of the network we adopted the valueof heterogeneity set in literature [21] to set up two kinds ofnodes with different initial energies namely the normalnodes with lower initial energy and the advanced nodes withhigher initial energy Advanced nodes are more likely tobecome CHs and not easy to die than normal nodes which isto balance energy consumption At the same time the totalenergy of the network has changed If the initial energy of thenormal node is Eo the initial energy of the advanced node is(1 + a) middot Eo So the total energy of the network is changed to(1 minus m) middot Eo + m middot (1 + a) middot Eo (1 + a middot m) middot Eo that is thetotal energy of the network has increased by 1 + am timesAccordingly in the CH election the optimal probability ofthe node becoming the CH has also been changed e
weighted probabilities of normal nodes and advanced nodesare shown in the following equations respectively
pnrm popt
1 + α middot m (5)
padv popt
1 + αmtimes(1 + a) (6)
e optimal CH number is kopt n2π
radicmiddot
EfsEmp
1113969middot
md2toBS [30] where kopt represents the optimal cluster
number n is the number of nodes set in the monitoring areaMtimesM and dtoBS represents the distance between the CHand the BS
For normal nodes the modified election threshold isshown in equation (7) Similarly the election threshold foradvanced nodes is shown in equation (8)
T(i)
pnrm
1 minus pnrm times mod r round 1pnrm( 1113857( 1113857times
Er(i) + Eh(i r minus 1)
Eo
i isin G
0 i notin G
⎧⎪⎪⎪⎪⎨
⎪⎪⎪⎪⎩
(7)
T(i)
padv
1 minus padv times mod r round 1padv( 1113857( 1113857times
Er(i) + Eh(i r minus 1)
Eo
i isin G
0 i notin G
⎧⎪⎪⎨
⎪⎪⎩(8)
In the above two threshold equations it can be foundthat the weighted probabilities are different because theadvanced node has more initial energy Due to the energyfactor is taken into account when electing the CH the higherthe energy is the easier it is to become the CH so theadvanced nodes are more likely to become the CHs than thenormal nodes
35 FOI-LEACH Routing Protocol FOI-LEACH protocolintroduces the concepts of ldquoself-energizedrdquo and ldquozonerdquocombined with the characteristics of field instrument net-working In addition the CH election stage and cluster
formation stage are carried out in each zone respectivelye flow of each round of the FOI-LEACH protocol isshown in Figure 3 and the specific operation steps aredescribed as follows
(1) After the deployment of the network nodes eachnode estimates the distance from the BS according tothe signal strength transmitted by the BS judges andidentifies the zone to which it belongs
(2) At the beginning of the CH election the nodegenerates a random number from 0 to 1 counts thecurrent residual energy Er(i) and the previous roundof energy replenishment Eh(i r minus 1) and determines
ABC
Figure 2 Partitioning method in the routing protocol
6 Journal of Electrical and Computer Engineering
whether the node is an advanced node Moreover ifit is an advanced node it calculates the threshold asshown in equation (8) otherwise it calculates thethreshold as shown in equation (7) and then judgeswhether the random number generated by the nodeis lower than the threshold if so announce themessage that it becomes the CH otherwise it be-comes a member node and waits for the schedulingof the CH
(3) After the CH election according to the BS radiomessage all the nodes maximum distance dmax andminimum dmin of network nodes to the BS and thedistance d(i BS) of the current node to the BS arestatistically counted and the current residual energy ofthe node Er(i) and the energy supply of the previousround Eh(i r minus 1) are calculated and then clustercompetition radii are computed e node detects thereceived announcement message and determineswhether the CH exists within the competition radiusof the zone If so a CH is selected according to thecompetition radius to join and form a cluster If thereis no CH within the competitive radius it automat-ically becomes a CH and publishes a notice
(4) After the cluster is formed the CH creates a TDMAschedule and the member nodes in the cluster waitfor the CH to be scheduled
(5) In the data transmission stage cluster member nodescollect data regularly and send the data directly to theCH through the single-hop transmission e CHcompresses and fuses the received data and thensends it to the nearest CH in the next zone until it istransmitted to the BS Loop through steps 1 to 5 untilthe network fails
4 Network Model of FieldObservation Instruments
41 Network Model In this paper we consider the randomdeployment of n nodes in a square monitoring area with asize of MtimesM e assumptions for the networking envi-ronment are as follows
All networking nodes have unique IDs and areheterogeneousAll networking nodes are randomly deployed in themonitoring area and cannot be moved afterdeploymentAll networking nodes know their residual energy andsome nodes can supplement the energyAll networking nodes can determine the distance fromthe information source according to the intensity of thereceived information
Start
Base station broadcastscluster head election
Node i generatesrandom number t (01)
Is it an advancednode
Becomes the ordinary node and waits for the cluster head node
to broadcast information
Yes
Request to join the nearest cluster
Enter the data transfer phasepartition autonomous multihop
mechanism
Waiting for the scheduling of the cluster head
Cluster headselection
The formationof the cluster
Create aschedule
Datatransmission
After a period oftime
NotltT(n)nrm tltT(n)advYes
Becomes the clusterhead nodes and
broadcasts the message
Waiting for theordinary node to
request to join
Create the TDMAschedule table
Yes
No No
The node performsself-energizing
End
Becomes the clusterhead node and
broadcasts the message
Waiting for theordinary node to
request to join
Create the TDMAschedule table
Figure 3 Flow chart of operation in each round of FOI-LEACH protocol
Journal of Electrical and Computer Engineering 7
e BS is located outside the monitoring area it hassufficient energy resources and each node knows thelocation of the BS
42 Energy Model Energy consumption is an importantcriterion to evaluate the performance of a routing protocole network life mainly depends on the energy consumed indata sending and data receiving Meanwhile the energyconsumed by the CH when using the fusion technologyshould be considered and the energy consumption of thenode in the process of calculation and storage should beneglected LEACH protocol uses first-order wireless mode inWSNs so it adopts a simple energy consumptionmodel [12]e model defines that the energy consumed by each l bitdata sent by the wireless circuit is
ETx(l d) ETxminuselec(l d) + ETxminusamp(l d)
lEelec + lEfsd
2 dlt d0
lEelec + lEmpd4 dge d0
⎧⎨
⎩
(9)
When receiving information the energy consumed bythe wireless circuit receiving l bit data is
ERx(l d) ERxminuselec(l d) lEelec (10)
e energy consumed by data fusion is
EGx lEgather (11)
In equations (9)-(10) d represents the distance betweenthe sending node and the receiving node and Eelec representsthe energy consumed for each bit of data sent or received Inequation (9) Efsd
2 is the energy consumed by the free spacemodel for each l bit of data amplification and Empd4 is theenergy consumed by the multipath attenuation model foreach l bit of data amplification Obviously when the distancebetween nodes becomes more extensive the energy con-sumption increases exponentially erefore if you want toreduce the energy consumption of data transmission youmust reduce the distance between nodes e Egather inequation (11) is expressed as the energy consumed by datafusion for each processing of 1 bit the d0 in equation (9) is athreshold which is determined by the equation (12) and isdefined as 87m in this paper
d0
Efs
Emp
1113971
(12)
5 Simulation Experiments and Analysis
51 Experimental Setting In order to analyze the perfor-mance of the FOI-LEACH protocol this paper conductssimulation experiments onMATLAB simulation platform tocompare it with the original LEACH protocol [4] SEPprotocol [21] and PECRP protocol [31] e simulationexperiments were carried out under the monitoring area of100mtimes 100m and the BS is located outside the monitoringarea with the coordinate of (150 50) As shown in Figure 4
the initial node distribution map distinguishes the nodes ineach zone by color in which red represents the nodes in zoneA blue represents the nodes in zone B and the greenrepresents the nodes in zone C And ldquordquo means the normalnode ldquo+rdquo means the advanced node and ldquotimesrdquo means BS
In the self-energy experiment all the surviving nodes inthe network are replenished with energy once every fiverounds until the simulation end e recharge energy isdistributed randomly to all remaining surviving nodes in thenetwork e total energy of the first replenishment is set to035 J In the later replenishment in order to prevent thenodes in the network from dying when there are too fewnodes We set the attenuation factor alpha to 09 that is theenergy replenishment to all the nodes in the network is 09times of the previous timee initial energy and topology ofall the experimental networks were set to the same envi-ronment When all the nodes in the network die the net-work is considered to be invalid Experiments proved thatthe network works best when the parameters are set to thefollowing valuesm is set to 01 a is set to 2 α is set to 03 andβ is set to 07e range of optimal CH number is [1 14] and10 is taken in this paper the probability of optimal CHnumber is popt 0 1 e three-partition system shown inFigure 2 was adopted in the routing protocol e specificparameters of the simulation experiments are listed inTable 1
52 Determination of the Partitioning Scheme e FOI-LEACH protocol proposed in this paper is based on theimprovement of the LEACH protocol In the initial stage ofnode deployment the distance between the node and the BSis obtained according to the signal strength of the BS re-ceived by the node en the monitoring area is partitionedaccording to the distance To determine the optimal parti-tioning scheme in the FOI-LEACH protocol we proposedthe following five schemes for the protocol and tested themin the partitioning experiment
Scheme 1 e monitoring area is divided into twozones A and B and the zone SA of A is equal to thezone SB of B as shown in Figure 5 (partitioning scheme1) e CH in zone B chooses the CH in zone A closest
0 50 100 1500
10
20
30
40
50
60
70
80
90
100
Advanced node
Normal node
BS
Figure 4 Distribution diagram of initial nodes
8 Journal of Electrical and Computer Engineering
to it for forwarding data and the CHs in zone Acommunicates directly with the BSScheme 2 As shown in Figure 5 (partitioning scheme2) the monitoring area is divided into two zones A andB and the SA of zone A is smaller than the area SB ofzone BScheme 3 e monitoring area is divided into threezones A B and C and the area SA of zone A is equalto the area SB of zone B and smaller than the area SC
of zone C as shown in Figure 5 (partitioning scheme3)Scheme 4 e monitoring area is divided into threezones A B and C and the area SA of zone A is smallerthan the area SB of zone B and smaller than the area SC
of zone C as shown in Figure 5 (partitioning scheme 4)Scheme 5 e monitoring area is divided into threezones A B and C and the area SA of zone A is equal tothe area SC of zone C and smaller than the area SB ofzone B as shown in Figure 5 (partitioning scheme 5)
e survival nodes and the average residual energy ineach round of the five partitioning schemes are drawn inFigures 6 and 7 respectively Based on the experimentalanalysis it can be found that Scheme 3 indicated as a redcurve in the figures has a better performance In scheme 3ie SA SB lt SC the first dead node appears in the 587thround which is later than other schemes that is thestability period is more extended than other schemes eaverage residual energy consumption rate of nodes is alsolower than that of other schemes is is because zones Aand B need to bear more forwarding energy so when thesetwo zones are smaller than zone C the network energyconsumption is more balanced erefore we adopted thepartitioning method of scheme 3 to carry out the simu-lation experiments
53 Analysis of Parameters In equation (4) parameters αand β determine the difference in cluster size erefore therelationship between these two parameters and network lifewas observed by taking α from 0 to 1 and β from 1 to 0 eresults of parameters analysis are shown in Figure 8 whichalso proves the rationality of our unequal clusteringmechanism When parameter α increases from 0 to 1 theeffect of the unequal clustering method is noticeableHowever the impact of parameter β on the network shouldalso be considered If the value of α is too large the lifetimeof the system will be shortened It is because too manyclusters will be generated near the BS and each cluster sendspackets to the BS which results in the waste of energyerefore it needs to determine the optimal values forparameters α and β In this experiment we can concludefrom Figure 8 that when α 0 3 and β 0 7 the death timeof the first node is later and the network is more stable
54 Experimental Comparison Analysis is paper mainlyevaluates the performance of the observation instrumentnetwork routing protocol with and without energy supplythrough the following evaluation elements
Network lifetime the network lifetime is measured bythe survival rate of the whole network nodes whichgenerally represents a certain proportion of the energyloss of the network node In this paper we took thedeath time interval from the beginning of the networkto the last surviving node as the lifetime of the networkEnergy consumption rate it usually refers to the av-erage energy consumption of a node sending or re-ceiving a byte of data It is essential to evaluate theperformance of routing algorithmsStability the stability of the field instruments obser-vation network was evaluated from two aspects thetime interval from the beginning of the network to thedeath of the first node and the number of CHsNetwork throughput the indicator to measure theefficiency of the network which is usually judged by thetotal number of packets sent to BS and the total numberof packets sent to CH
541 Experiments without Energy Supply
(1) Network Lifetime Figure 9 shows the number of sur-viving nodes in the network when the network runs for 2100rounds without being self-energized According to thestatistics of the number of rounds of death node in Table 2the network failure of the LEACH protocol occurs at round276 the network of SEP protocol expires at 462 rounds andnetwork failure of the PECRP protocol at round 438However the FOI-LEACH protocol was not expired untilround 2042 which significantly increased the networksurvival time It is because the FOI-LEACH protocol con-siders such factors as energy and distance in stages of CHelection cluster formation and intercluster communication
Table 1 Parameters in the simulation experiments
Parameter ValueTotal number of nodes N 100Network area (m) 100times100Coordinates of BS (m) (150 50)Data packet size L (bit) 4000Initial energy of normal node (J) 01Initial energy of advanced node (J) 03Energy consumption of transmitting circuit ETX (nJbit) 50
Energy consumption of receiving circuit ERX (nJbit) 50Free space model energy Efs (pJbitm
2) 10Multipath attenuation model energy Emp (pJbitm2) 00013Energy consumption of data fusion EDA (nJbit) 5Probability of the optimal number of CHs popt 01Maximum cluster radius in zone A RcA (m) 125Maximum cluster radius in zone B RcB (m) 125Maximum cluster radius in zone C RcC (m) 25Attenuation factor alpha 09M 01A 2α 03β 07
Journal of Electrical and Computer Engineering 9
AB
(a)
AB
(b)
ABC
(c)
ABC
(d)
ABC
(e)
Figure 5 Partitioning scheme (a) Partitioning scheme 1 SaltSb (b) Partitioning scheme 2 SaSb (c) Partitioning scheme 1 SaSbltSc (d)Partitioning scheme 1 SaltSbltSc (e) Partitioning scheme 1 SaScltSb
AeqBAsBAeqBsC
AsBsCAeqCsB
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
Figure 6 Comparison of active nodes in each round
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
002
004
006
008
01
012
Ave
rage
resid
ual e
nerg
y
AeqBAsBAeqBsC
AsBsCAeqCsB
Figure 7 Comparison of average residual energy in each round
10 Journal of Electrical and Computer Engineering
(2) Average Residual Energy and Energy Dissipation RateFigure 10 shows the graph of the average residual energy ofthe network running 2100 rounds without being self-en-ergized Combined with the network average residual en-ergy which is shown in Table 3 it can be drawn that the FOI-LEACH protocol is more slowly energy consumed Besidesit can be seen from Figure 10 that the energy consumption
rate of the improved network is significantly reduced toachieve the purpose of delaying energy consumption andextending network life
(3) Stability e stability of networking was evaluated fromtwo aspects First it can be seen from Figure 9 that the FOI-LEACH protocol significantly extends the death time of the
Self-energized
400
420
440
460
480
500
520
540
Dea
th ti
me o
f the
firs
t nod
e
01 02 03 04 05 06 07 08 09 10α
Figure 8 Impact of parameters α and β on the network lifetime
LEACHSEP
PECRPImproved protocol
400
160060
0
2000
1000
1200
140020
0
1800
21000
800
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
Figure 9 Comparison of live nodes in each round without power supply
Table 2 Statistics number of rounds of dead nodes of the four protocols without power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 135 160 204 276SEP 174 191 226 462PECRP 338 374 412 438FOI-LEACH 481 684 1272 2042
Journal of Electrical and Computer Engineering 11
first node For the LEACH protocol the nodes began to dieat round 135 SEP protocol at round 174 and PECRPprotocol at round 338 Because the energy factor is takeninto account in selecting the CH energy and distance factorsare taken into account in clustering and the adopted zone-based autonomous multihop communication model mini-mizes the Hello control package the nodes die at round 481for the FOI-LEACH protocol As a result the FOI-LEACHprotocol has better performance than other protocols
Figure 11 shows the distribution of the number ofclusters of the four protocols without energy supply simulatedfor 10 rounds of random elections in which Figure 11(a)represents the statistics number of CHs in each zone of theFOI-LEACH protocol and Figure 11(b) represents the sta-tistics number of CHs in the whole network of FOI-LEACHprotocol Figures 11(c)ndash11(e) represent the statistics numberof CHs of LEACH SEP and PECRP protocols respectively Itcan be seen that the number of CHs of FOI-LEACH protocolis more stable than that of LEACH SEP and PECRP BecauseLEACH and SEP randomly select CHs the number of CHsproduced was unstable e FOI-LEACH protocol formsclusters by selecting CHs with a competitive radius and thenumber of CHs is relatively stable
(4) Network (roughput Figure 12 shows that in theLEACH protocol SEP protocol PECRP protocol and ourproposed FOI-LEACH protocol the total number of packets
sent to BS is approximately 900 2580 2980 and 11140respectively Moreover Figure 13 shows that in the LEACHprotocol SEP protocol PECRP protocol and FOI-LEACHprotocol the total number of packages sent to CHs is ap-proximately 7500 21000 38200 and 119000 respectively Itis because the proposed scheme has a high network lifetimethe total number of packets sent to BS and CHs is muchhigher than other protocols
542 Experiments with Energy Supply
(1) Network Lifetime Figure 14 shows the number of sur-viving nodes in the network when the network runs for 2300rounds self-energized According to the statistics of deathnodes in Table 4 we can find that the network lifetime of thefour protocols all has been extended e network failure ofthe LEACH protocol occurred at round 341 the network ofthe SEP protocol expires at round 665 and network failure ofPECRP protocol at round 530 and the FOI-LEACH pro-tocol was not expired until round 2246 which significantlyincreased the network survival time It is demonstrated thatthe improved schemes can work well in both the environ-ments with or without power supply
(2) Average Residual Energy and Energy Dissipation RateFigure 15 shows the graph of the average residual energy ofthe network running 2300 rounds self-energized Combinedwith the network average residual energy which shown inTable 5 it can be drawn that the FOI-LEACH protocol ismore slowly energy consumed Besides it can be seen fromFigure 15 that the energy consumption rate of the improvednetwork is significantly reduced to achieve the purpose ofdelaying energy consumption and extending network life
(3) Stability For the stability of field instruments net-working it can be seen from Figure 14 that the FOI-LEACHprotocol significantly extends the death time of the first
1800
2000
1000
1600
210060
0
200
8000
120040
0
1400
Number of rounds
0
002
004
006
008
01
012
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 10 Comparison of average residual energy in each round without power supply
Table 3 Statistics of the average residual energy (J) of nodes of thefour protocols without power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0075 0007 0 0SEP 0094 002 0 0PECRP 0088 0053 0 0FOI-LEACH 0113 0092 0043 152times10minus5
12 Journal of Electrical and Computer Engineering
ABC
0
1
2
3
4
5
6
7Co
mpa
rison
of C
Hs i
n ea
ch re
gion
2 3 4 5 6 7 8 9 101Number of rounds
(a)
0
2
4
6
8
10
12
14
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(d)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 11 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol without power supply
Journal of Electrical and Computer Engineering 13
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
2000
4000
6000
8000
10000
12000
Pack
ets t
o BS
LEACHSEP
PECRPImproved protocol
Figure 12 Comparison of packets sent to BS from CHs without power supply
times104
200
400
600
800
1000
1200
2000
1800
21000
1400
1600
Number of rounds
0
2
4
6
8
10
12
Pack
ets t
o CH
LEACHSEP
PECRPImproved protocol
Figure 13 Comparison of packets sent to CHs from member nodes without power supply
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
LEACHSEP
PECRPImproved protocol
Figure 14 Comparison of live nodes in each round with power supply
14 Journal of Electrical and Computer Engineering
Table 4 Statistics number of rounds of dead nodes of the four protocols with power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 177 204 232 341SEP 185 210 264 665PECRP 392 430 493 530FOI-LEACH 555 716 1238 2246
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
002
004
006
008
01
012
014
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 15 Comparison of average residual energy in each round with power supply
Table 5 Statistics of the average residual energy (J) of nodes of the four protocols with power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0086 0018 0 0SEP 0105 0036 0001 0PECRP 0099 007 0 0FOI-LEACH 0124 0109 0062 0001
0
1
2
3
4
5
6
7
8
Com
paris
on o
f CH
s in
each
regi
on
2 3 4 5 6 7 8 9 101Number of rounds
ABC
(a)
0
2
4
6
8
10
12
1415
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
Figure 16 Continued
Journal of Electrical and Computer Engineering 15
0
2
4
6
8
10
12
14
16N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14
16
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(d)
0
2
4
6
8
10
12
14
16
18
20
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 16 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol with power supply
0
2000
4000
6000
8000
10000
12000
14000
Pack
ets t
o BS
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 17 Comparison of packets sent to BS from CHs with power supply
16 Journal of Electrical and Computer Engineering
node e supplied energy promotes the extension of thenetwork lifetime and the stability of the networking for thefour protocols in varying degrees For the LEACH protocolthe node began to die at round 177 SEP protocol at round185 PECRP protocol at round 392 and round 555 for theimproved FOI-LEACH protocol
e distributions of the number of clusters in the fourprotocols with energy supply simulated for 10 rounds ofrandom elections are shown in Figure 16 Like the previousfigures Figure 16(a) represents the statistics number of CHsof each zone of FOI-LEACH protocol Figures 16(b)ndash16(e)represent the statistics number of CHs of FOI-LEACHprotocol LEACH protocol SEP protocol and PECRPprotocol respectively Due to the efficient schemes of CHselecting and clustering the FOI-LEACH protocol showssignificantly better performance than the other threeprotocols
(4) Network (roughput In the environment of self-energyas shown in Figure 17 the total number of packets sent toBS of the LEACH protocol SEP protocol PECRP protocoland the proposed FOI-LEACH protocol is approximately2428 3080 3746 and 13265 respectively Moreover inFigure 18 the total number of packages sent to CHs of theLEACH protocol SEP protocol PECRP protocol andFOI-LEACH protocol is approximately 21400 2430044000 and 123200 respectively We can find that the totalnumber of packets sent by our protocol to BS and CHs ismuch higher than the other protocols which also dem-onstrated that the proposed protocol has a better networkthroughout
6 Conclusions
According to the characteristics of field observation in-strument networking an improved protocol FOI-LEACHbased on LEACH protocol was proposed in this paper Byconsidering the energy factor in the CH election threshold
and referring to the SEP protocol to set up two kinds ofnodes with different initial energies which are calledadvanced nodes and normal nodes the network model offield observation instruments has been established Inaddition to solve the problem that the LEACH protocolconsumes much energy during transmission and results inuneven energy consumption for the direct and long-distance transmission the improved protocol adopted the3 zones of partitioning mechanism and the multihoptransmission mechanism to alleviate and avoid the ldquohotspotrdquo problems Furthermore energy supplies were addedto the nodes in A and B zones that are responsible formore energy transmission so as to balance the energyconsumption of the network and prolong the networklifetime In the simulation experiments we compared theperformance of the FOI-LEACH protocol with theLEACH SEP and PECRP protocols in two cases with orwithout energy supply Comparing performance indica-tors of network lifetime energy consumption rate sta-bility and network throughput the proposed FOI-LEACH protocol can slow down the death of nodes andthe energy consumption rate obviously and shows asignificantly better performance than other three proto-cols e experimental results demonstrated that the FOI-LEACH protocol could balance network energy con-sumption and alleviate the ldquohot spotrdquo problem to extendthe lifetime of network nodes in the field observationinstruments network e future work is to implementand port the improved protocol to the hardware of net-working node we designed and developed previously andtest and verify the feasibility and stability of the protocolin the actual situation
Data Availability
e initial nodes are generated randomly in the networkand there are no observation data used in the simulationexperiments
0
20000
40000
60000
80000
100000
120000
140000
Pack
ets t
o CH
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 18 Comparison of packets sent to CHs from nodes with power supply
Journal of Electrical and Computer Engineering 17
Conflicts of Interest
e authors declare that there are no conflicts of interest
Acknowledgments
is work was supported by the National Nature ScienceFoundation of China (Grant no 61862038) the LanzhouTalent Innovation and Entrepreneurship Technology PlanProject (no 2019-RC-14) and the Foundation of a HundredYouth Talents Training Program of Lanzhou JiaotongUniversity
References
[1] J Y Huo Z N Ren and Y R Yang A Kind of InstrumentNetwork Node Equipment and Monitoring System ChinesePatents Beijing China 2017
[2] J Y Huo Key Technology and Application Research ofE-Science Virtual Joint Observation System for Geoscience inCold and Dry Regions University of Chinese Academy ofSciences Beijing China 2012
[3] I F Akyildiz W L Weilian Su Y Sankarasubramaniam andE Cayirci ldquoA survey on sensor networksrdquo IEEE Communi-cations Magazine vol 40 no 8 pp 102ndash114 2002
[4] W R Heinzelman A Chandrakasan and H BalakrishnanldquoEnergy-efficient communication protocol for wirelessmicrosensor networksrdquo in Proceedings of the 33rd HawaiiIntentional Conference on System Sciences Maui HI USAJanuary 2000
[5] D Mehta and S Saxena ldquoA comparative analysis of energyefficient hierarchical routing protocols for wireless sensornetworksrdquo in Proceedings of the 2018 4th InternationalConference on Computing Sciences (ICCS) pp 53ndash58Jalandhar India August 2018
[6] C Karlof and D Wagner ldquoSecure routing in wireless sensornetworks attacks and countermeasuresrdquo Ad Hoc Networksvol 1 2003
[7] L B Oliveira A Ferreira M A Vilaca et al ldquoSecLEACH-onthe security of clustered sensor networksrdquo Signal Processingvol 87 2007
[8] Y Y Gu GW Bai and J J Tao ldquoAZM-LEACH autonomouszone-based multi-hop routing protocol in WSNsrdquo ComputerEngineering and Applications vol 47 no 20 pp 58ndash61 2011
[9] L XWang Research on Routing Technology ofWireless SensorNetworks Based on Data Aggregation Shenyang LigongUniversity Shenyang China 2015
[10] J P Shao Research on Key Energy-Efficient Routing Tech-nology of WSN Based on Cluster Shenyang Ligong UniversityShenyang China 2015
[11] V K Arora V Sharma and M Sachdeva ldquoA survey onLEACH and otherrsquos routing protocols in wireless sensornetworkrdquo Optik vol 127 no 16 pp 6590ndash6600 2016
[12] W B Heinzelman A P Chandrakasan and H BalakrishnanldquoAn application-specific protocol architecture for wirelessmicrosensor networksrdquo IEEE Transactions on WirelessCommunications vol 1 no 4 pp 660ndash670 2002
[13] S Al-Sodairi and R Ouni ldquoReliable and energy-efficientmulti-hop LEACH-based clustering protocol for wirelesssensor networksrdquo Sustainable Computing Informatics andSystems vol 20 pp 1ndash13 2018
[14] O Younis and S Fahmy ldquoHEED a hybrid energy-efficientdistributed clustering approach for ad hoc sensor networksrdquo
IEEE Transactions on Mobile Computing vol 3 no 4pp 366ndash379 2004
[15] B B Chen and Y L Shi ldquoWSN routing protocol based oncluster heads selection in regionsrdquo Computer Engineeringvol 37 no 19 pp 96ndash98 2011
[16] P Azada ldquoCluster head selection in wireless sensor networksunder fuzzy environmentrdquo ISRN Sensor Networks vol 2013Article ID 909086 8 pages 2013
[17] S Soro and W B Heinzelman ldquoCluster head election tech-niques for coverage preservation in wireless sensor networksrdquoAd Hoc Networks vol 7 no 5 pp 955ndash972 2009
[18] A akkar ldquoDEAL distance and energy based advancedleach protocolrdquo in Proceedings of the International Conferenceon Information and Communication Technology for IntelligentSystems pp 370ndash376 Ahmedabad India March 2017
[19] T Y Chang W N Liu Y Zhang and H Y Li ldquoOptimizedLEACH protocol based on distance and energy of clusterheadrdquo Journal of Hebei University (Natural Science Edition)vol 39 no 2 pp 194ndash200 2019
[20] P Mehra M Doja and B Alam ldquoStability enhancement inLEACH (SE-LEACH) for homogeneousWSNrdquo EAI EndorsedTransactions on Scalable Information Systems vol 6 no 20pp 1ndash9 2019
[21] G Smaragdakis I Matta and A Bestavros ldquoSEP a stableelection protocol for clustered heterogeneous wireless sensornetworksrdquo in Proceedings of the Second InternationalWorkshop on Sensor and Actor Network Protocols and Ap-plications (SANPA 2004) pp 1ndash11 Boston MA USA June2004
[22] F S Hu and Q Xiao ldquoMulti-hop routing algorithm of energy-balancing based on LEACHrdquo Journal of Chinese ComputerSystems vol 35 no 1 pp 72ndash75 2014
[23] C F Li M Ye G H Chen and J Wu ldquoAn energy-efficientunequal clustering mechanism for wireless sensor networksrdquoin Proceedings of the IEEE International Conference on MobileAdhoc and Sensor Systems Conference p 604 WashingtonDC USA November 2005
[24] E Alnawafa I Marghescu and MHT ldquoMulti-hop techniquefor the improvement of leach protocolrdquo in Proceedings of the2016 15th RoEduNet Conference Networking in Education andResearch pp 1ndash5 Bucharest Romania September 2016
[25] E Alnawafa and I Marghescu ldquoIMHT improved MHT-LEACH protocol for wireless sensor networksrdquo in Proceedingsof the 2017 8th International Conference on Information andCommunication Systems (ICICS) pp 246ndash251 Irbid JordanApril 2017
[26] J Y Huo Z Zhang and C Tao ldquoUsing IPv6 address ad-vantage to build Network Node of Field observation In-struments in cold and arid areasrdquo China Education Networkno 5 pp 45-46 2018
[27] L Mateu and F Moll ldquoReview of energy harvesting tech-niques and applications for microelectronicsrdquo in Proceedingsof the International Society for Optical Engineering pp 359ndash373 Bellingham WA USA October 2005
[28] G Wang and R Y Wang ldquoRouting algorithm based oncluster-head optimization for self-energized wireless sensornetworkrdquo Journal of Computer Applications vol 38 no 334pp 201ndash216 2018
[29] X P Fan X Yang S Q Liu and Z H Qu ldquoClusteringrouting algorithm for wireless sensor networks with powerharvestingrdquo Computer Engineering vol 39 no 11 pp 126ndash134 2008
18 Journal of Electrical and Computer Engineering
[30] C H Zhang ldquoStudy on the energy heterogeneous clusteringrouting protocol for wireless sensor networksrdquo Science ampTechnology Vision no 13 pp 71+164ndash165 2012
[31] T Liu and F Li ldquoPower-efficient clustering routing protocolbased on applications in wireless sensor networkrdquo in Pro-ceedings of the International Conference on Wireless Com-munications IEEE Press Melbourne Australia September2009
Journal of Electrical and Computer Engineering 19
34 Analysis of Heterogeneity In this paper in order toprolong the stable stage of the network we adopted the valueof heterogeneity set in literature [21] to set up two kinds ofnodes with different initial energies namely the normalnodes with lower initial energy and the advanced nodes withhigher initial energy Advanced nodes are more likely tobecome CHs and not easy to die than normal nodes which isto balance energy consumption At the same time the totalenergy of the network has changed If the initial energy of thenormal node is Eo the initial energy of the advanced node is(1 + a) middot Eo So the total energy of the network is changed to(1 minus m) middot Eo + m middot (1 + a) middot Eo (1 + a middot m) middot Eo that is thetotal energy of the network has increased by 1 + am timesAccordingly in the CH election the optimal probability ofthe node becoming the CH has also been changed e
weighted probabilities of normal nodes and advanced nodesare shown in the following equations respectively
pnrm popt
1 + α middot m (5)
padv popt
1 + αmtimes(1 + a) (6)
e optimal CH number is kopt n2π
radicmiddot
EfsEmp
1113969middot
md2toBS [30] where kopt represents the optimal cluster
number n is the number of nodes set in the monitoring areaMtimesM and dtoBS represents the distance between the CHand the BS
For normal nodes the modified election threshold isshown in equation (7) Similarly the election threshold foradvanced nodes is shown in equation (8)
T(i)
pnrm
1 minus pnrm times mod r round 1pnrm( 1113857( 1113857times
Er(i) + Eh(i r minus 1)
Eo
i isin G
0 i notin G
⎧⎪⎪⎪⎪⎨
⎪⎪⎪⎪⎩
(7)
T(i)
padv
1 minus padv times mod r round 1padv( 1113857( 1113857times
Er(i) + Eh(i r minus 1)
Eo
i isin G
0 i notin G
⎧⎪⎪⎨
⎪⎪⎩(8)
In the above two threshold equations it can be foundthat the weighted probabilities are different because theadvanced node has more initial energy Due to the energyfactor is taken into account when electing the CH the higherthe energy is the easier it is to become the CH so theadvanced nodes are more likely to become the CHs than thenormal nodes
35 FOI-LEACH Routing Protocol FOI-LEACH protocolintroduces the concepts of ldquoself-energizedrdquo and ldquozonerdquocombined with the characteristics of field instrument net-working In addition the CH election stage and cluster
formation stage are carried out in each zone respectivelye flow of each round of the FOI-LEACH protocol isshown in Figure 3 and the specific operation steps aredescribed as follows
(1) After the deployment of the network nodes eachnode estimates the distance from the BS according tothe signal strength transmitted by the BS judges andidentifies the zone to which it belongs
(2) At the beginning of the CH election the nodegenerates a random number from 0 to 1 counts thecurrent residual energy Er(i) and the previous roundof energy replenishment Eh(i r minus 1) and determines
ABC
Figure 2 Partitioning method in the routing protocol
6 Journal of Electrical and Computer Engineering
whether the node is an advanced node Moreover ifit is an advanced node it calculates the threshold asshown in equation (8) otherwise it calculates thethreshold as shown in equation (7) and then judgeswhether the random number generated by the nodeis lower than the threshold if so announce themessage that it becomes the CH otherwise it be-comes a member node and waits for the schedulingof the CH
(3) After the CH election according to the BS radiomessage all the nodes maximum distance dmax andminimum dmin of network nodes to the BS and thedistance d(i BS) of the current node to the BS arestatistically counted and the current residual energy ofthe node Er(i) and the energy supply of the previousround Eh(i r minus 1) are calculated and then clustercompetition radii are computed e node detects thereceived announcement message and determineswhether the CH exists within the competition radiusof the zone If so a CH is selected according to thecompetition radius to join and form a cluster If thereis no CH within the competitive radius it automat-ically becomes a CH and publishes a notice
(4) After the cluster is formed the CH creates a TDMAschedule and the member nodes in the cluster waitfor the CH to be scheduled
(5) In the data transmission stage cluster member nodescollect data regularly and send the data directly to theCH through the single-hop transmission e CHcompresses and fuses the received data and thensends it to the nearest CH in the next zone until it istransmitted to the BS Loop through steps 1 to 5 untilthe network fails
4 Network Model of FieldObservation Instruments
41 Network Model In this paper we consider the randomdeployment of n nodes in a square monitoring area with asize of MtimesM e assumptions for the networking envi-ronment are as follows
All networking nodes have unique IDs and areheterogeneousAll networking nodes are randomly deployed in themonitoring area and cannot be moved afterdeploymentAll networking nodes know their residual energy andsome nodes can supplement the energyAll networking nodes can determine the distance fromthe information source according to the intensity of thereceived information
Start
Base station broadcastscluster head election
Node i generatesrandom number t (01)
Is it an advancednode
Becomes the ordinary node and waits for the cluster head node
to broadcast information
Yes
Request to join the nearest cluster
Enter the data transfer phasepartition autonomous multihop
mechanism
Waiting for the scheduling of the cluster head
Cluster headselection
The formationof the cluster
Create aschedule
Datatransmission
After a period oftime
NotltT(n)nrm tltT(n)advYes
Becomes the clusterhead nodes and
broadcasts the message
Waiting for theordinary node to
request to join
Create the TDMAschedule table
Yes
No No
The node performsself-energizing
End
Becomes the clusterhead node and
broadcasts the message
Waiting for theordinary node to
request to join
Create the TDMAschedule table
Figure 3 Flow chart of operation in each round of FOI-LEACH protocol
Journal of Electrical and Computer Engineering 7
e BS is located outside the monitoring area it hassufficient energy resources and each node knows thelocation of the BS
42 Energy Model Energy consumption is an importantcriterion to evaluate the performance of a routing protocole network life mainly depends on the energy consumed indata sending and data receiving Meanwhile the energyconsumed by the CH when using the fusion technologyshould be considered and the energy consumption of thenode in the process of calculation and storage should beneglected LEACH protocol uses first-order wireless mode inWSNs so it adopts a simple energy consumptionmodel [12]e model defines that the energy consumed by each l bitdata sent by the wireless circuit is
ETx(l d) ETxminuselec(l d) + ETxminusamp(l d)
lEelec + lEfsd
2 dlt d0
lEelec + lEmpd4 dge d0
⎧⎨
⎩
(9)
When receiving information the energy consumed bythe wireless circuit receiving l bit data is
ERx(l d) ERxminuselec(l d) lEelec (10)
e energy consumed by data fusion is
EGx lEgather (11)
In equations (9)-(10) d represents the distance betweenthe sending node and the receiving node and Eelec representsthe energy consumed for each bit of data sent or received Inequation (9) Efsd
2 is the energy consumed by the free spacemodel for each l bit of data amplification and Empd4 is theenergy consumed by the multipath attenuation model foreach l bit of data amplification Obviously when the distancebetween nodes becomes more extensive the energy con-sumption increases exponentially erefore if you want toreduce the energy consumption of data transmission youmust reduce the distance between nodes e Egather inequation (11) is expressed as the energy consumed by datafusion for each processing of 1 bit the d0 in equation (9) is athreshold which is determined by the equation (12) and isdefined as 87m in this paper
d0
Efs
Emp
1113971
(12)
5 Simulation Experiments and Analysis
51 Experimental Setting In order to analyze the perfor-mance of the FOI-LEACH protocol this paper conductssimulation experiments onMATLAB simulation platform tocompare it with the original LEACH protocol [4] SEPprotocol [21] and PECRP protocol [31] e simulationexperiments were carried out under the monitoring area of100mtimes 100m and the BS is located outside the monitoringarea with the coordinate of (150 50) As shown in Figure 4
the initial node distribution map distinguishes the nodes ineach zone by color in which red represents the nodes in zoneA blue represents the nodes in zone B and the greenrepresents the nodes in zone C And ldquordquo means the normalnode ldquo+rdquo means the advanced node and ldquotimesrdquo means BS
In the self-energy experiment all the surviving nodes inthe network are replenished with energy once every fiverounds until the simulation end e recharge energy isdistributed randomly to all remaining surviving nodes in thenetwork e total energy of the first replenishment is set to035 J In the later replenishment in order to prevent thenodes in the network from dying when there are too fewnodes We set the attenuation factor alpha to 09 that is theenergy replenishment to all the nodes in the network is 09times of the previous timee initial energy and topology ofall the experimental networks were set to the same envi-ronment When all the nodes in the network die the net-work is considered to be invalid Experiments proved thatthe network works best when the parameters are set to thefollowing valuesm is set to 01 a is set to 2 α is set to 03 andβ is set to 07e range of optimal CH number is [1 14] and10 is taken in this paper the probability of optimal CHnumber is popt 0 1 e three-partition system shown inFigure 2 was adopted in the routing protocol e specificparameters of the simulation experiments are listed inTable 1
52 Determination of the Partitioning Scheme e FOI-LEACH protocol proposed in this paper is based on theimprovement of the LEACH protocol In the initial stage ofnode deployment the distance between the node and the BSis obtained according to the signal strength of the BS re-ceived by the node en the monitoring area is partitionedaccording to the distance To determine the optimal parti-tioning scheme in the FOI-LEACH protocol we proposedthe following five schemes for the protocol and tested themin the partitioning experiment
Scheme 1 e monitoring area is divided into twozones A and B and the zone SA of A is equal to thezone SB of B as shown in Figure 5 (partitioning scheme1) e CH in zone B chooses the CH in zone A closest
0 50 100 1500
10
20
30
40
50
60
70
80
90
100
Advanced node
Normal node
BS
Figure 4 Distribution diagram of initial nodes
8 Journal of Electrical and Computer Engineering
to it for forwarding data and the CHs in zone Acommunicates directly with the BSScheme 2 As shown in Figure 5 (partitioning scheme2) the monitoring area is divided into two zones A andB and the SA of zone A is smaller than the area SB ofzone BScheme 3 e monitoring area is divided into threezones A B and C and the area SA of zone A is equalto the area SB of zone B and smaller than the area SC
of zone C as shown in Figure 5 (partitioning scheme3)Scheme 4 e monitoring area is divided into threezones A B and C and the area SA of zone A is smallerthan the area SB of zone B and smaller than the area SC
of zone C as shown in Figure 5 (partitioning scheme 4)Scheme 5 e monitoring area is divided into threezones A B and C and the area SA of zone A is equal tothe area SC of zone C and smaller than the area SB ofzone B as shown in Figure 5 (partitioning scheme 5)
e survival nodes and the average residual energy ineach round of the five partitioning schemes are drawn inFigures 6 and 7 respectively Based on the experimentalanalysis it can be found that Scheme 3 indicated as a redcurve in the figures has a better performance In scheme 3ie SA SB lt SC the first dead node appears in the 587thround which is later than other schemes that is thestability period is more extended than other schemes eaverage residual energy consumption rate of nodes is alsolower than that of other schemes is is because zones Aand B need to bear more forwarding energy so when thesetwo zones are smaller than zone C the network energyconsumption is more balanced erefore we adopted thepartitioning method of scheme 3 to carry out the simu-lation experiments
53 Analysis of Parameters In equation (4) parameters αand β determine the difference in cluster size erefore therelationship between these two parameters and network lifewas observed by taking α from 0 to 1 and β from 1 to 0 eresults of parameters analysis are shown in Figure 8 whichalso proves the rationality of our unequal clusteringmechanism When parameter α increases from 0 to 1 theeffect of the unequal clustering method is noticeableHowever the impact of parameter β on the network shouldalso be considered If the value of α is too large the lifetimeof the system will be shortened It is because too manyclusters will be generated near the BS and each cluster sendspackets to the BS which results in the waste of energyerefore it needs to determine the optimal values forparameters α and β In this experiment we can concludefrom Figure 8 that when α 0 3 and β 0 7 the death timeof the first node is later and the network is more stable
54 Experimental Comparison Analysis is paper mainlyevaluates the performance of the observation instrumentnetwork routing protocol with and without energy supplythrough the following evaluation elements
Network lifetime the network lifetime is measured bythe survival rate of the whole network nodes whichgenerally represents a certain proportion of the energyloss of the network node In this paper we took thedeath time interval from the beginning of the networkto the last surviving node as the lifetime of the networkEnergy consumption rate it usually refers to the av-erage energy consumption of a node sending or re-ceiving a byte of data It is essential to evaluate theperformance of routing algorithmsStability the stability of the field instruments obser-vation network was evaluated from two aspects thetime interval from the beginning of the network to thedeath of the first node and the number of CHsNetwork throughput the indicator to measure theefficiency of the network which is usually judged by thetotal number of packets sent to BS and the total numberof packets sent to CH
541 Experiments without Energy Supply
(1) Network Lifetime Figure 9 shows the number of sur-viving nodes in the network when the network runs for 2100rounds without being self-energized According to thestatistics of the number of rounds of death node in Table 2the network failure of the LEACH protocol occurs at round276 the network of SEP protocol expires at 462 rounds andnetwork failure of the PECRP protocol at round 438However the FOI-LEACH protocol was not expired untilround 2042 which significantly increased the networksurvival time It is because the FOI-LEACH protocol con-siders such factors as energy and distance in stages of CHelection cluster formation and intercluster communication
Table 1 Parameters in the simulation experiments
Parameter ValueTotal number of nodes N 100Network area (m) 100times100Coordinates of BS (m) (150 50)Data packet size L (bit) 4000Initial energy of normal node (J) 01Initial energy of advanced node (J) 03Energy consumption of transmitting circuit ETX (nJbit) 50
Energy consumption of receiving circuit ERX (nJbit) 50Free space model energy Efs (pJbitm
2) 10Multipath attenuation model energy Emp (pJbitm2) 00013Energy consumption of data fusion EDA (nJbit) 5Probability of the optimal number of CHs popt 01Maximum cluster radius in zone A RcA (m) 125Maximum cluster radius in zone B RcB (m) 125Maximum cluster radius in zone C RcC (m) 25Attenuation factor alpha 09M 01A 2α 03β 07
Journal of Electrical and Computer Engineering 9
AB
(a)
AB
(b)
ABC
(c)
ABC
(d)
ABC
(e)
Figure 5 Partitioning scheme (a) Partitioning scheme 1 SaltSb (b) Partitioning scheme 2 SaSb (c) Partitioning scheme 1 SaSbltSc (d)Partitioning scheme 1 SaltSbltSc (e) Partitioning scheme 1 SaScltSb
AeqBAsBAeqBsC
AsBsCAeqCsB
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
Figure 6 Comparison of active nodes in each round
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
002
004
006
008
01
012
Ave
rage
resid
ual e
nerg
y
AeqBAsBAeqBsC
AsBsCAeqCsB
Figure 7 Comparison of average residual energy in each round
10 Journal of Electrical and Computer Engineering
(2) Average Residual Energy and Energy Dissipation RateFigure 10 shows the graph of the average residual energy ofthe network running 2100 rounds without being self-en-ergized Combined with the network average residual en-ergy which is shown in Table 3 it can be drawn that the FOI-LEACH protocol is more slowly energy consumed Besidesit can be seen from Figure 10 that the energy consumption
rate of the improved network is significantly reduced toachieve the purpose of delaying energy consumption andextending network life
(3) Stability e stability of networking was evaluated fromtwo aspects First it can be seen from Figure 9 that the FOI-LEACH protocol significantly extends the death time of the
Self-energized
400
420
440
460
480
500
520
540
Dea
th ti
me o
f the
firs
t nod
e
01 02 03 04 05 06 07 08 09 10α
Figure 8 Impact of parameters α and β on the network lifetime
LEACHSEP
PECRPImproved protocol
400
160060
0
2000
1000
1200
140020
0
1800
21000
800
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
Figure 9 Comparison of live nodes in each round without power supply
Table 2 Statistics number of rounds of dead nodes of the four protocols without power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 135 160 204 276SEP 174 191 226 462PECRP 338 374 412 438FOI-LEACH 481 684 1272 2042
Journal of Electrical and Computer Engineering 11
first node For the LEACH protocol the nodes began to dieat round 135 SEP protocol at round 174 and PECRPprotocol at round 338 Because the energy factor is takeninto account in selecting the CH energy and distance factorsare taken into account in clustering and the adopted zone-based autonomous multihop communication model mini-mizes the Hello control package the nodes die at round 481for the FOI-LEACH protocol As a result the FOI-LEACHprotocol has better performance than other protocols
Figure 11 shows the distribution of the number ofclusters of the four protocols without energy supply simulatedfor 10 rounds of random elections in which Figure 11(a)represents the statistics number of CHs in each zone of theFOI-LEACH protocol and Figure 11(b) represents the sta-tistics number of CHs in the whole network of FOI-LEACHprotocol Figures 11(c)ndash11(e) represent the statistics numberof CHs of LEACH SEP and PECRP protocols respectively Itcan be seen that the number of CHs of FOI-LEACH protocolis more stable than that of LEACH SEP and PECRP BecauseLEACH and SEP randomly select CHs the number of CHsproduced was unstable e FOI-LEACH protocol formsclusters by selecting CHs with a competitive radius and thenumber of CHs is relatively stable
(4) Network (roughput Figure 12 shows that in theLEACH protocol SEP protocol PECRP protocol and ourproposed FOI-LEACH protocol the total number of packets
sent to BS is approximately 900 2580 2980 and 11140respectively Moreover Figure 13 shows that in the LEACHprotocol SEP protocol PECRP protocol and FOI-LEACHprotocol the total number of packages sent to CHs is ap-proximately 7500 21000 38200 and 119000 respectively Itis because the proposed scheme has a high network lifetimethe total number of packets sent to BS and CHs is muchhigher than other protocols
542 Experiments with Energy Supply
(1) Network Lifetime Figure 14 shows the number of sur-viving nodes in the network when the network runs for 2300rounds self-energized According to the statistics of deathnodes in Table 4 we can find that the network lifetime of thefour protocols all has been extended e network failure ofthe LEACH protocol occurred at round 341 the network ofthe SEP protocol expires at round 665 and network failure ofPECRP protocol at round 530 and the FOI-LEACH pro-tocol was not expired until round 2246 which significantlyincreased the network survival time It is demonstrated thatthe improved schemes can work well in both the environ-ments with or without power supply
(2) Average Residual Energy and Energy Dissipation RateFigure 15 shows the graph of the average residual energy ofthe network running 2300 rounds self-energized Combinedwith the network average residual energy which shown inTable 5 it can be drawn that the FOI-LEACH protocol ismore slowly energy consumed Besides it can be seen fromFigure 15 that the energy consumption rate of the improvednetwork is significantly reduced to achieve the purpose ofdelaying energy consumption and extending network life
(3) Stability For the stability of field instruments net-working it can be seen from Figure 14 that the FOI-LEACHprotocol significantly extends the death time of the first
1800
2000
1000
1600
210060
0
200
8000
120040
0
1400
Number of rounds
0
002
004
006
008
01
012
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 10 Comparison of average residual energy in each round without power supply
Table 3 Statistics of the average residual energy (J) of nodes of thefour protocols without power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0075 0007 0 0SEP 0094 002 0 0PECRP 0088 0053 0 0FOI-LEACH 0113 0092 0043 152times10minus5
12 Journal of Electrical and Computer Engineering
ABC
0
1
2
3
4
5
6
7Co
mpa
rison
of C
Hs i
n ea
ch re
gion
2 3 4 5 6 7 8 9 101Number of rounds
(a)
0
2
4
6
8
10
12
14
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(d)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 11 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol without power supply
Journal of Electrical and Computer Engineering 13
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
2000
4000
6000
8000
10000
12000
Pack
ets t
o BS
LEACHSEP
PECRPImproved protocol
Figure 12 Comparison of packets sent to BS from CHs without power supply
times104
200
400
600
800
1000
1200
2000
1800
21000
1400
1600
Number of rounds
0
2
4
6
8
10
12
Pack
ets t
o CH
LEACHSEP
PECRPImproved protocol
Figure 13 Comparison of packets sent to CHs from member nodes without power supply
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
LEACHSEP
PECRPImproved protocol
Figure 14 Comparison of live nodes in each round with power supply
14 Journal of Electrical and Computer Engineering
Table 4 Statistics number of rounds of dead nodes of the four protocols with power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 177 204 232 341SEP 185 210 264 665PECRP 392 430 493 530FOI-LEACH 555 716 1238 2246
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
002
004
006
008
01
012
014
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 15 Comparison of average residual energy in each round with power supply
Table 5 Statistics of the average residual energy (J) of nodes of the four protocols with power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0086 0018 0 0SEP 0105 0036 0001 0PECRP 0099 007 0 0FOI-LEACH 0124 0109 0062 0001
0
1
2
3
4
5
6
7
8
Com
paris
on o
f CH
s in
each
regi
on
2 3 4 5 6 7 8 9 101Number of rounds
ABC
(a)
0
2
4
6
8
10
12
1415
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
Figure 16 Continued
Journal of Electrical and Computer Engineering 15
0
2
4
6
8
10
12
14
16N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14
16
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(d)
0
2
4
6
8
10
12
14
16
18
20
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 16 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol with power supply
0
2000
4000
6000
8000
10000
12000
14000
Pack
ets t
o BS
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 17 Comparison of packets sent to BS from CHs with power supply
16 Journal of Electrical and Computer Engineering
node e supplied energy promotes the extension of thenetwork lifetime and the stability of the networking for thefour protocols in varying degrees For the LEACH protocolthe node began to die at round 177 SEP protocol at round185 PECRP protocol at round 392 and round 555 for theimproved FOI-LEACH protocol
e distributions of the number of clusters in the fourprotocols with energy supply simulated for 10 rounds ofrandom elections are shown in Figure 16 Like the previousfigures Figure 16(a) represents the statistics number of CHsof each zone of FOI-LEACH protocol Figures 16(b)ndash16(e)represent the statistics number of CHs of FOI-LEACHprotocol LEACH protocol SEP protocol and PECRPprotocol respectively Due to the efficient schemes of CHselecting and clustering the FOI-LEACH protocol showssignificantly better performance than the other threeprotocols
(4) Network (roughput In the environment of self-energyas shown in Figure 17 the total number of packets sent toBS of the LEACH protocol SEP protocol PECRP protocoland the proposed FOI-LEACH protocol is approximately2428 3080 3746 and 13265 respectively Moreover inFigure 18 the total number of packages sent to CHs of theLEACH protocol SEP protocol PECRP protocol andFOI-LEACH protocol is approximately 21400 2430044000 and 123200 respectively We can find that the totalnumber of packets sent by our protocol to BS and CHs ismuch higher than the other protocols which also dem-onstrated that the proposed protocol has a better networkthroughout
6 Conclusions
According to the characteristics of field observation in-strument networking an improved protocol FOI-LEACHbased on LEACH protocol was proposed in this paper Byconsidering the energy factor in the CH election threshold
and referring to the SEP protocol to set up two kinds ofnodes with different initial energies which are calledadvanced nodes and normal nodes the network model offield observation instruments has been established Inaddition to solve the problem that the LEACH protocolconsumes much energy during transmission and results inuneven energy consumption for the direct and long-distance transmission the improved protocol adopted the3 zones of partitioning mechanism and the multihoptransmission mechanism to alleviate and avoid the ldquohotspotrdquo problems Furthermore energy supplies were addedto the nodes in A and B zones that are responsible formore energy transmission so as to balance the energyconsumption of the network and prolong the networklifetime In the simulation experiments we compared theperformance of the FOI-LEACH protocol with theLEACH SEP and PECRP protocols in two cases with orwithout energy supply Comparing performance indica-tors of network lifetime energy consumption rate sta-bility and network throughput the proposed FOI-LEACH protocol can slow down the death of nodes andthe energy consumption rate obviously and shows asignificantly better performance than other three proto-cols e experimental results demonstrated that the FOI-LEACH protocol could balance network energy con-sumption and alleviate the ldquohot spotrdquo problem to extendthe lifetime of network nodes in the field observationinstruments network e future work is to implementand port the improved protocol to the hardware of net-working node we designed and developed previously andtest and verify the feasibility and stability of the protocolin the actual situation
Data Availability
e initial nodes are generated randomly in the networkand there are no observation data used in the simulationexperiments
0
20000
40000
60000
80000
100000
120000
140000
Pack
ets t
o CH
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 18 Comparison of packets sent to CHs from nodes with power supply
Journal of Electrical and Computer Engineering 17
Conflicts of Interest
e authors declare that there are no conflicts of interest
Acknowledgments
is work was supported by the National Nature ScienceFoundation of China (Grant no 61862038) the LanzhouTalent Innovation and Entrepreneurship Technology PlanProject (no 2019-RC-14) and the Foundation of a HundredYouth Talents Training Program of Lanzhou JiaotongUniversity
References
[1] J Y Huo Z N Ren and Y R Yang A Kind of InstrumentNetwork Node Equipment and Monitoring System ChinesePatents Beijing China 2017
[2] J Y Huo Key Technology and Application Research ofE-Science Virtual Joint Observation System for Geoscience inCold and Dry Regions University of Chinese Academy ofSciences Beijing China 2012
[3] I F Akyildiz W L Weilian Su Y Sankarasubramaniam andE Cayirci ldquoA survey on sensor networksrdquo IEEE Communi-cations Magazine vol 40 no 8 pp 102ndash114 2002
[4] W R Heinzelman A Chandrakasan and H BalakrishnanldquoEnergy-efficient communication protocol for wirelessmicrosensor networksrdquo in Proceedings of the 33rd HawaiiIntentional Conference on System Sciences Maui HI USAJanuary 2000
[5] D Mehta and S Saxena ldquoA comparative analysis of energyefficient hierarchical routing protocols for wireless sensornetworksrdquo in Proceedings of the 2018 4th InternationalConference on Computing Sciences (ICCS) pp 53ndash58Jalandhar India August 2018
[6] C Karlof and D Wagner ldquoSecure routing in wireless sensornetworks attacks and countermeasuresrdquo Ad Hoc Networksvol 1 2003
[7] L B Oliveira A Ferreira M A Vilaca et al ldquoSecLEACH-onthe security of clustered sensor networksrdquo Signal Processingvol 87 2007
[8] Y Y Gu GW Bai and J J Tao ldquoAZM-LEACH autonomouszone-based multi-hop routing protocol in WSNsrdquo ComputerEngineering and Applications vol 47 no 20 pp 58ndash61 2011
[9] L XWang Research on Routing Technology ofWireless SensorNetworks Based on Data Aggregation Shenyang LigongUniversity Shenyang China 2015
[10] J P Shao Research on Key Energy-Efficient Routing Tech-nology of WSN Based on Cluster Shenyang Ligong UniversityShenyang China 2015
[11] V K Arora V Sharma and M Sachdeva ldquoA survey onLEACH and otherrsquos routing protocols in wireless sensornetworkrdquo Optik vol 127 no 16 pp 6590ndash6600 2016
[12] W B Heinzelman A P Chandrakasan and H BalakrishnanldquoAn application-specific protocol architecture for wirelessmicrosensor networksrdquo IEEE Transactions on WirelessCommunications vol 1 no 4 pp 660ndash670 2002
[13] S Al-Sodairi and R Ouni ldquoReliable and energy-efficientmulti-hop LEACH-based clustering protocol for wirelesssensor networksrdquo Sustainable Computing Informatics andSystems vol 20 pp 1ndash13 2018
[14] O Younis and S Fahmy ldquoHEED a hybrid energy-efficientdistributed clustering approach for ad hoc sensor networksrdquo
IEEE Transactions on Mobile Computing vol 3 no 4pp 366ndash379 2004
[15] B B Chen and Y L Shi ldquoWSN routing protocol based oncluster heads selection in regionsrdquo Computer Engineeringvol 37 no 19 pp 96ndash98 2011
[16] P Azada ldquoCluster head selection in wireless sensor networksunder fuzzy environmentrdquo ISRN Sensor Networks vol 2013Article ID 909086 8 pages 2013
[17] S Soro and W B Heinzelman ldquoCluster head election tech-niques for coverage preservation in wireless sensor networksrdquoAd Hoc Networks vol 7 no 5 pp 955ndash972 2009
[18] A akkar ldquoDEAL distance and energy based advancedleach protocolrdquo in Proceedings of the International Conferenceon Information and Communication Technology for IntelligentSystems pp 370ndash376 Ahmedabad India March 2017
[19] T Y Chang W N Liu Y Zhang and H Y Li ldquoOptimizedLEACH protocol based on distance and energy of clusterheadrdquo Journal of Hebei University (Natural Science Edition)vol 39 no 2 pp 194ndash200 2019
[20] P Mehra M Doja and B Alam ldquoStability enhancement inLEACH (SE-LEACH) for homogeneousWSNrdquo EAI EndorsedTransactions on Scalable Information Systems vol 6 no 20pp 1ndash9 2019
[21] G Smaragdakis I Matta and A Bestavros ldquoSEP a stableelection protocol for clustered heterogeneous wireless sensornetworksrdquo in Proceedings of the Second InternationalWorkshop on Sensor and Actor Network Protocols and Ap-plications (SANPA 2004) pp 1ndash11 Boston MA USA June2004
[22] F S Hu and Q Xiao ldquoMulti-hop routing algorithm of energy-balancing based on LEACHrdquo Journal of Chinese ComputerSystems vol 35 no 1 pp 72ndash75 2014
[23] C F Li M Ye G H Chen and J Wu ldquoAn energy-efficientunequal clustering mechanism for wireless sensor networksrdquoin Proceedings of the IEEE International Conference on MobileAdhoc and Sensor Systems Conference p 604 WashingtonDC USA November 2005
[24] E Alnawafa I Marghescu and MHT ldquoMulti-hop techniquefor the improvement of leach protocolrdquo in Proceedings of the2016 15th RoEduNet Conference Networking in Education andResearch pp 1ndash5 Bucharest Romania September 2016
[25] E Alnawafa and I Marghescu ldquoIMHT improved MHT-LEACH protocol for wireless sensor networksrdquo in Proceedingsof the 2017 8th International Conference on Information andCommunication Systems (ICICS) pp 246ndash251 Irbid JordanApril 2017
[26] J Y Huo Z Zhang and C Tao ldquoUsing IPv6 address ad-vantage to build Network Node of Field observation In-struments in cold and arid areasrdquo China Education Networkno 5 pp 45-46 2018
[27] L Mateu and F Moll ldquoReview of energy harvesting tech-niques and applications for microelectronicsrdquo in Proceedingsof the International Society for Optical Engineering pp 359ndash373 Bellingham WA USA October 2005
[28] G Wang and R Y Wang ldquoRouting algorithm based oncluster-head optimization for self-energized wireless sensornetworkrdquo Journal of Computer Applications vol 38 no 334pp 201ndash216 2018
[29] X P Fan X Yang S Q Liu and Z H Qu ldquoClusteringrouting algorithm for wireless sensor networks with powerharvestingrdquo Computer Engineering vol 39 no 11 pp 126ndash134 2008
18 Journal of Electrical and Computer Engineering
[30] C H Zhang ldquoStudy on the energy heterogeneous clusteringrouting protocol for wireless sensor networksrdquo Science ampTechnology Vision no 13 pp 71+164ndash165 2012
[31] T Liu and F Li ldquoPower-efficient clustering routing protocolbased on applications in wireless sensor networkrdquo in Pro-ceedings of the International Conference on Wireless Com-munications IEEE Press Melbourne Australia September2009
Journal of Electrical and Computer Engineering 19
whether the node is an advanced node Moreover ifit is an advanced node it calculates the threshold asshown in equation (8) otherwise it calculates thethreshold as shown in equation (7) and then judgeswhether the random number generated by the nodeis lower than the threshold if so announce themessage that it becomes the CH otherwise it be-comes a member node and waits for the schedulingof the CH
(3) After the CH election according to the BS radiomessage all the nodes maximum distance dmax andminimum dmin of network nodes to the BS and thedistance d(i BS) of the current node to the BS arestatistically counted and the current residual energy ofthe node Er(i) and the energy supply of the previousround Eh(i r minus 1) are calculated and then clustercompetition radii are computed e node detects thereceived announcement message and determineswhether the CH exists within the competition radiusof the zone If so a CH is selected according to thecompetition radius to join and form a cluster If thereis no CH within the competitive radius it automat-ically becomes a CH and publishes a notice
(4) After the cluster is formed the CH creates a TDMAschedule and the member nodes in the cluster waitfor the CH to be scheduled
(5) In the data transmission stage cluster member nodescollect data regularly and send the data directly to theCH through the single-hop transmission e CHcompresses and fuses the received data and thensends it to the nearest CH in the next zone until it istransmitted to the BS Loop through steps 1 to 5 untilthe network fails
4 Network Model of FieldObservation Instruments
41 Network Model In this paper we consider the randomdeployment of n nodes in a square monitoring area with asize of MtimesM e assumptions for the networking envi-ronment are as follows
All networking nodes have unique IDs and areheterogeneousAll networking nodes are randomly deployed in themonitoring area and cannot be moved afterdeploymentAll networking nodes know their residual energy andsome nodes can supplement the energyAll networking nodes can determine the distance fromthe information source according to the intensity of thereceived information
Start
Base station broadcastscluster head election
Node i generatesrandom number t (01)
Is it an advancednode
Becomes the ordinary node and waits for the cluster head node
to broadcast information
Yes
Request to join the nearest cluster
Enter the data transfer phasepartition autonomous multihop
mechanism
Waiting for the scheduling of the cluster head
Cluster headselection
The formationof the cluster
Create aschedule
Datatransmission
After a period oftime
NotltT(n)nrm tltT(n)advYes
Becomes the clusterhead nodes and
broadcasts the message
Waiting for theordinary node to
request to join
Create the TDMAschedule table
Yes
No No
The node performsself-energizing
End
Becomes the clusterhead node and
broadcasts the message
Waiting for theordinary node to
request to join
Create the TDMAschedule table
Figure 3 Flow chart of operation in each round of FOI-LEACH protocol
Journal of Electrical and Computer Engineering 7
e BS is located outside the monitoring area it hassufficient energy resources and each node knows thelocation of the BS
42 Energy Model Energy consumption is an importantcriterion to evaluate the performance of a routing protocole network life mainly depends on the energy consumed indata sending and data receiving Meanwhile the energyconsumed by the CH when using the fusion technologyshould be considered and the energy consumption of thenode in the process of calculation and storage should beneglected LEACH protocol uses first-order wireless mode inWSNs so it adopts a simple energy consumptionmodel [12]e model defines that the energy consumed by each l bitdata sent by the wireless circuit is
ETx(l d) ETxminuselec(l d) + ETxminusamp(l d)
lEelec + lEfsd
2 dlt d0
lEelec + lEmpd4 dge d0
⎧⎨
⎩
(9)
When receiving information the energy consumed bythe wireless circuit receiving l bit data is
ERx(l d) ERxminuselec(l d) lEelec (10)
e energy consumed by data fusion is
EGx lEgather (11)
In equations (9)-(10) d represents the distance betweenthe sending node and the receiving node and Eelec representsthe energy consumed for each bit of data sent or received Inequation (9) Efsd
2 is the energy consumed by the free spacemodel for each l bit of data amplification and Empd4 is theenergy consumed by the multipath attenuation model foreach l bit of data amplification Obviously when the distancebetween nodes becomes more extensive the energy con-sumption increases exponentially erefore if you want toreduce the energy consumption of data transmission youmust reduce the distance between nodes e Egather inequation (11) is expressed as the energy consumed by datafusion for each processing of 1 bit the d0 in equation (9) is athreshold which is determined by the equation (12) and isdefined as 87m in this paper
d0
Efs
Emp
1113971
(12)
5 Simulation Experiments and Analysis
51 Experimental Setting In order to analyze the perfor-mance of the FOI-LEACH protocol this paper conductssimulation experiments onMATLAB simulation platform tocompare it with the original LEACH protocol [4] SEPprotocol [21] and PECRP protocol [31] e simulationexperiments were carried out under the monitoring area of100mtimes 100m and the BS is located outside the monitoringarea with the coordinate of (150 50) As shown in Figure 4
the initial node distribution map distinguishes the nodes ineach zone by color in which red represents the nodes in zoneA blue represents the nodes in zone B and the greenrepresents the nodes in zone C And ldquordquo means the normalnode ldquo+rdquo means the advanced node and ldquotimesrdquo means BS
In the self-energy experiment all the surviving nodes inthe network are replenished with energy once every fiverounds until the simulation end e recharge energy isdistributed randomly to all remaining surviving nodes in thenetwork e total energy of the first replenishment is set to035 J In the later replenishment in order to prevent thenodes in the network from dying when there are too fewnodes We set the attenuation factor alpha to 09 that is theenergy replenishment to all the nodes in the network is 09times of the previous timee initial energy and topology ofall the experimental networks were set to the same envi-ronment When all the nodes in the network die the net-work is considered to be invalid Experiments proved thatthe network works best when the parameters are set to thefollowing valuesm is set to 01 a is set to 2 α is set to 03 andβ is set to 07e range of optimal CH number is [1 14] and10 is taken in this paper the probability of optimal CHnumber is popt 0 1 e three-partition system shown inFigure 2 was adopted in the routing protocol e specificparameters of the simulation experiments are listed inTable 1
52 Determination of the Partitioning Scheme e FOI-LEACH protocol proposed in this paper is based on theimprovement of the LEACH protocol In the initial stage ofnode deployment the distance between the node and the BSis obtained according to the signal strength of the BS re-ceived by the node en the monitoring area is partitionedaccording to the distance To determine the optimal parti-tioning scheme in the FOI-LEACH protocol we proposedthe following five schemes for the protocol and tested themin the partitioning experiment
Scheme 1 e monitoring area is divided into twozones A and B and the zone SA of A is equal to thezone SB of B as shown in Figure 5 (partitioning scheme1) e CH in zone B chooses the CH in zone A closest
0 50 100 1500
10
20
30
40
50
60
70
80
90
100
Advanced node
Normal node
BS
Figure 4 Distribution diagram of initial nodes
8 Journal of Electrical and Computer Engineering
to it for forwarding data and the CHs in zone Acommunicates directly with the BSScheme 2 As shown in Figure 5 (partitioning scheme2) the monitoring area is divided into two zones A andB and the SA of zone A is smaller than the area SB ofzone BScheme 3 e monitoring area is divided into threezones A B and C and the area SA of zone A is equalto the area SB of zone B and smaller than the area SC
of zone C as shown in Figure 5 (partitioning scheme3)Scheme 4 e monitoring area is divided into threezones A B and C and the area SA of zone A is smallerthan the area SB of zone B and smaller than the area SC
of zone C as shown in Figure 5 (partitioning scheme 4)Scheme 5 e monitoring area is divided into threezones A B and C and the area SA of zone A is equal tothe area SC of zone C and smaller than the area SB ofzone B as shown in Figure 5 (partitioning scheme 5)
e survival nodes and the average residual energy ineach round of the five partitioning schemes are drawn inFigures 6 and 7 respectively Based on the experimentalanalysis it can be found that Scheme 3 indicated as a redcurve in the figures has a better performance In scheme 3ie SA SB lt SC the first dead node appears in the 587thround which is later than other schemes that is thestability period is more extended than other schemes eaverage residual energy consumption rate of nodes is alsolower than that of other schemes is is because zones Aand B need to bear more forwarding energy so when thesetwo zones are smaller than zone C the network energyconsumption is more balanced erefore we adopted thepartitioning method of scheme 3 to carry out the simu-lation experiments
53 Analysis of Parameters In equation (4) parameters αand β determine the difference in cluster size erefore therelationship between these two parameters and network lifewas observed by taking α from 0 to 1 and β from 1 to 0 eresults of parameters analysis are shown in Figure 8 whichalso proves the rationality of our unequal clusteringmechanism When parameter α increases from 0 to 1 theeffect of the unequal clustering method is noticeableHowever the impact of parameter β on the network shouldalso be considered If the value of α is too large the lifetimeof the system will be shortened It is because too manyclusters will be generated near the BS and each cluster sendspackets to the BS which results in the waste of energyerefore it needs to determine the optimal values forparameters α and β In this experiment we can concludefrom Figure 8 that when α 0 3 and β 0 7 the death timeof the first node is later and the network is more stable
54 Experimental Comparison Analysis is paper mainlyevaluates the performance of the observation instrumentnetwork routing protocol with and without energy supplythrough the following evaluation elements
Network lifetime the network lifetime is measured bythe survival rate of the whole network nodes whichgenerally represents a certain proportion of the energyloss of the network node In this paper we took thedeath time interval from the beginning of the networkto the last surviving node as the lifetime of the networkEnergy consumption rate it usually refers to the av-erage energy consumption of a node sending or re-ceiving a byte of data It is essential to evaluate theperformance of routing algorithmsStability the stability of the field instruments obser-vation network was evaluated from two aspects thetime interval from the beginning of the network to thedeath of the first node and the number of CHsNetwork throughput the indicator to measure theefficiency of the network which is usually judged by thetotal number of packets sent to BS and the total numberof packets sent to CH
541 Experiments without Energy Supply
(1) Network Lifetime Figure 9 shows the number of sur-viving nodes in the network when the network runs for 2100rounds without being self-energized According to thestatistics of the number of rounds of death node in Table 2the network failure of the LEACH protocol occurs at round276 the network of SEP protocol expires at 462 rounds andnetwork failure of the PECRP protocol at round 438However the FOI-LEACH protocol was not expired untilround 2042 which significantly increased the networksurvival time It is because the FOI-LEACH protocol con-siders such factors as energy and distance in stages of CHelection cluster formation and intercluster communication
Table 1 Parameters in the simulation experiments
Parameter ValueTotal number of nodes N 100Network area (m) 100times100Coordinates of BS (m) (150 50)Data packet size L (bit) 4000Initial energy of normal node (J) 01Initial energy of advanced node (J) 03Energy consumption of transmitting circuit ETX (nJbit) 50
Energy consumption of receiving circuit ERX (nJbit) 50Free space model energy Efs (pJbitm
2) 10Multipath attenuation model energy Emp (pJbitm2) 00013Energy consumption of data fusion EDA (nJbit) 5Probability of the optimal number of CHs popt 01Maximum cluster radius in zone A RcA (m) 125Maximum cluster radius in zone B RcB (m) 125Maximum cluster radius in zone C RcC (m) 25Attenuation factor alpha 09M 01A 2α 03β 07
Journal of Electrical and Computer Engineering 9
AB
(a)
AB
(b)
ABC
(c)
ABC
(d)
ABC
(e)
Figure 5 Partitioning scheme (a) Partitioning scheme 1 SaltSb (b) Partitioning scheme 2 SaSb (c) Partitioning scheme 1 SaSbltSc (d)Partitioning scheme 1 SaltSbltSc (e) Partitioning scheme 1 SaScltSb
AeqBAsBAeqBsC
AsBsCAeqCsB
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
Figure 6 Comparison of active nodes in each round
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
002
004
006
008
01
012
Ave
rage
resid
ual e
nerg
y
AeqBAsBAeqBsC
AsBsCAeqCsB
Figure 7 Comparison of average residual energy in each round
10 Journal of Electrical and Computer Engineering
(2) Average Residual Energy and Energy Dissipation RateFigure 10 shows the graph of the average residual energy ofthe network running 2100 rounds without being self-en-ergized Combined with the network average residual en-ergy which is shown in Table 3 it can be drawn that the FOI-LEACH protocol is more slowly energy consumed Besidesit can be seen from Figure 10 that the energy consumption
rate of the improved network is significantly reduced toachieve the purpose of delaying energy consumption andextending network life
(3) Stability e stability of networking was evaluated fromtwo aspects First it can be seen from Figure 9 that the FOI-LEACH protocol significantly extends the death time of the
Self-energized
400
420
440
460
480
500
520
540
Dea
th ti
me o
f the
firs
t nod
e
01 02 03 04 05 06 07 08 09 10α
Figure 8 Impact of parameters α and β on the network lifetime
LEACHSEP
PECRPImproved protocol
400
160060
0
2000
1000
1200
140020
0
1800
21000
800
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
Figure 9 Comparison of live nodes in each round without power supply
Table 2 Statistics number of rounds of dead nodes of the four protocols without power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 135 160 204 276SEP 174 191 226 462PECRP 338 374 412 438FOI-LEACH 481 684 1272 2042
Journal of Electrical and Computer Engineering 11
first node For the LEACH protocol the nodes began to dieat round 135 SEP protocol at round 174 and PECRPprotocol at round 338 Because the energy factor is takeninto account in selecting the CH energy and distance factorsare taken into account in clustering and the adopted zone-based autonomous multihop communication model mini-mizes the Hello control package the nodes die at round 481for the FOI-LEACH protocol As a result the FOI-LEACHprotocol has better performance than other protocols
Figure 11 shows the distribution of the number ofclusters of the four protocols without energy supply simulatedfor 10 rounds of random elections in which Figure 11(a)represents the statistics number of CHs in each zone of theFOI-LEACH protocol and Figure 11(b) represents the sta-tistics number of CHs in the whole network of FOI-LEACHprotocol Figures 11(c)ndash11(e) represent the statistics numberof CHs of LEACH SEP and PECRP protocols respectively Itcan be seen that the number of CHs of FOI-LEACH protocolis more stable than that of LEACH SEP and PECRP BecauseLEACH and SEP randomly select CHs the number of CHsproduced was unstable e FOI-LEACH protocol formsclusters by selecting CHs with a competitive radius and thenumber of CHs is relatively stable
(4) Network (roughput Figure 12 shows that in theLEACH protocol SEP protocol PECRP protocol and ourproposed FOI-LEACH protocol the total number of packets
sent to BS is approximately 900 2580 2980 and 11140respectively Moreover Figure 13 shows that in the LEACHprotocol SEP protocol PECRP protocol and FOI-LEACHprotocol the total number of packages sent to CHs is ap-proximately 7500 21000 38200 and 119000 respectively Itis because the proposed scheme has a high network lifetimethe total number of packets sent to BS and CHs is muchhigher than other protocols
542 Experiments with Energy Supply
(1) Network Lifetime Figure 14 shows the number of sur-viving nodes in the network when the network runs for 2300rounds self-energized According to the statistics of deathnodes in Table 4 we can find that the network lifetime of thefour protocols all has been extended e network failure ofthe LEACH protocol occurred at round 341 the network ofthe SEP protocol expires at round 665 and network failure ofPECRP protocol at round 530 and the FOI-LEACH pro-tocol was not expired until round 2246 which significantlyincreased the network survival time It is demonstrated thatthe improved schemes can work well in both the environ-ments with or without power supply
(2) Average Residual Energy and Energy Dissipation RateFigure 15 shows the graph of the average residual energy ofthe network running 2300 rounds self-energized Combinedwith the network average residual energy which shown inTable 5 it can be drawn that the FOI-LEACH protocol ismore slowly energy consumed Besides it can be seen fromFigure 15 that the energy consumption rate of the improvednetwork is significantly reduced to achieve the purpose ofdelaying energy consumption and extending network life
(3) Stability For the stability of field instruments net-working it can be seen from Figure 14 that the FOI-LEACHprotocol significantly extends the death time of the first
1800
2000
1000
1600
210060
0
200
8000
120040
0
1400
Number of rounds
0
002
004
006
008
01
012
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 10 Comparison of average residual energy in each round without power supply
Table 3 Statistics of the average residual energy (J) of nodes of thefour protocols without power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0075 0007 0 0SEP 0094 002 0 0PECRP 0088 0053 0 0FOI-LEACH 0113 0092 0043 152times10minus5
12 Journal of Electrical and Computer Engineering
ABC
0
1
2
3
4
5
6
7Co
mpa
rison
of C
Hs i
n ea
ch re
gion
2 3 4 5 6 7 8 9 101Number of rounds
(a)
0
2
4
6
8
10
12
14
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(d)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 11 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol without power supply
Journal of Electrical and Computer Engineering 13
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
2000
4000
6000
8000
10000
12000
Pack
ets t
o BS
LEACHSEP
PECRPImproved protocol
Figure 12 Comparison of packets sent to BS from CHs without power supply
times104
200
400
600
800
1000
1200
2000
1800
21000
1400
1600
Number of rounds
0
2
4
6
8
10
12
Pack
ets t
o CH
LEACHSEP
PECRPImproved protocol
Figure 13 Comparison of packets sent to CHs from member nodes without power supply
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
LEACHSEP
PECRPImproved protocol
Figure 14 Comparison of live nodes in each round with power supply
14 Journal of Electrical and Computer Engineering
Table 4 Statistics number of rounds of dead nodes of the four protocols with power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 177 204 232 341SEP 185 210 264 665PECRP 392 430 493 530FOI-LEACH 555 716 1238 2246
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
002
004
006
008
01
012
014
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 15 Comparison of average residual energy in each round with power supply
Table 5 Statistics of the average residual energy (J) of nodes of the four protocols with power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0086 0018 0 0SEP 0105 0036 0001 0PECRP 0099 007 0 0FOI-LEACH 0124 0109 0062 0001
0
1
2
3
4
5
6
7
8
Com
paris
on o
f CH
s in
each
regi
on
2 3 4 5 6 7 8 9 101Number of rounds
ABC
(a)
0
2
4
6
8
10
12
1415
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
Figure 16 Continued
Journal of Electrical and Computer Engineering 15
0
2
4
6
8
10
12
14
16N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14
16
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(d)
0
2
4
6
8
10
12
14
16
18
20
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 16 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol with power supply
0
2000
4000
6000
8000
10000
12000
14000
Pack
ets t
o BS
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 17 Comparison of packets sent to BS from CHs with power supply
16 Journal of Electrical and Computer Engineering
node e supplied energy promotes the extension of thenetwork lifetime and the stability of the networking for thefour protocols in varying degrees For the LEACH protocolthe node began to die at round 177 SEP protocol at round185 PECRP protocol at round 392 and round 555 for theimproved FOI-LEACH protocol
e distributions of the number of clusters in the fourprotocols with energy supply simulated for 10 rounds ofrandom elections are shown in Figure 16 Like the previousfigures Figure 16(a) represents the statistics number of CHsof each zone of FOI-LEACH protocol Figures 16(b)ndash16(e)represent the statistics number of CHs of FOI-LEACHprotocol LEACH protocol SEP protocol and PECRPprotocol respectively Due to the efficient schemes of CHselecting and clustering the FOI-LEACH protocol showssignificantly better performance than the other threeprotocols
(4) Network (roughput In the environment of self-energyas shown in Figure 17 the total number of packets sent toBS of the LEACH protocol SEP protocol PECRP protocoland the proposed FOI-LEACH protocol is approximately2428 3080 3746 and 13265 respectively Moreover inFigure 18 the total number of packages sent to CHs of theLEACH protocol SEP protocol PECRP protocol andFOI-LEACH protocol is approximately 21400 2430044000 and 123200 respectively We can find that the totalnumber of packets sent by our protocol to BS and CHs ismuch higher than the other protocols which also dem-onstrated that the proposed protocol has a better networkthroughout
6 Conclusions
According to the characteristics of field observation in-strument networking an improved protocol FOI-LEACHbased on LEACH protocol was proposed in this paper Byconsidering the energy factor in the CH election threshold
and referring to the SEP protocol to set up two kinds ofnodes with different initial energies which are calledadvanced nodes and normal nodes the network model offield observation instruments has been established Inaddition to solve the problem that the LEACH protocolconsumes much energy during transmission and results inuneven energy consumption for the direct and long-distance transmission the improved protocol adopted the3 zones of partitioning mechanism and the multihoptransmission mechanism to alleviate and avoid the ldquohotspotrdquo problems Furthermore energy supplies were addedto the nodes in A and B zones that are responsible formore energy transmission so as to balance the energyconsumption of the network and prolong the networklifetime In the simulation experiments we compared theperformance of the FOI-LEACH protocol with theLEACH SEP and PECRP protocols in two cases with orwithout energy supply Comparing performance indica-tors of network lifetime energy consumption rate sta-bility and network throughput the proposed FOI-LEACH protocol can slow down the death of nodes andthe energy consumption rate obviously and shows asignificantly better performance than other three proto-cols e experimental results demonstrated that the FOI-LEACH protocol could balance network energy con-sumption and alleviate the ldquohot spotrdquo problem to extendthe lifetime of network nodes in the field observationinstruments network e future work is to implementand port the improved protocol to the hardware of net-working node we designed and developed previously andtest and verify the feasibility and stability of the protocolin the actual situation
Data Availability
e initial nodes are generated randomly in the networkand there are no observation data used in the simulationexperiments
0
20000
40000
60000
80000
100000
120000
140000
Pack
ets t
o CH
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 18 Comparison of packets sent to CHs from nodes with power supply
Journal of Electrical and Computer Engineering 17
Conflicts of Interest
e authors declare that there are no conflicts of interest
Acknowledgments
is work was supported by the National Nature ScienceFoundation of China (Grant no 61862038) the LanzhouTalent Innovation and Entrepreneurship Technology PlanProject (no 2019-RC-14) and the Foundation of a HundredYouth Talents Training Program of Lanzhou JiaotongUniversity
References
[1] J Y Huo Z N Ren and Y R Yang A Kind of InstrumentNetwork Node Equipment and Monitoring System ChinesePatents Beijing China 2017
[2] J Y Huo Key Technology and Application Research ofE-Science Virtual Joint Observation System for Geoscience inCold and Dry Regions University of Chinese Academy ofSciences Beijing China 2012
[3] I F Akyildiz W L Weilian Su Y Sankarasubramaniam andE Cayirci ldquoA survey on sensor networksrdquo IEEE Communi-cations Magazine vol 40 no 8 pp 102ndash114 2002
[4] W R Heinzelman A Chandrakasan and H BalakrishnanldquoEnergy-efficient communication protocol for wirelessmicrosensor networksrdquo in Proceedings of the 33rd HawaiiIntentional Conference on System Sciences Maui HI USAJanuary 2000
[5] D Mehta and S Saxena ldquoA comparative analysis of energyefficient hierarchical routing protocols for wireless sensornetworksrdquo in Proceedings of the 2018 4th InternationalConference on Computing Sciences (ICCS) pp 53ndash58Jalandhar India August 2018
[6] C Karlof and D Wagner ldquoSecure routing in wireless sensornetworks attacks and countermeasuresrdquo Ad Hoc Networksvol 1 2003
[7] L B Oliveira A Ferreira M A Vilaca et al ldquoSecLEACH-onthe security of clustered sensor networksrdquo Signal Processingvol 87 2007
[8] Y Y Gu GW Bai and J J Tao ldquoAZM-LEACH autonomouszone-based multi-hop routing protocol in WSNsrdquo ComputerEngineering and Applications vol 47 no 20 pp 58ndash61 2011
[9] L XWang Research on Routing Technology ofWireless SensorNetworks Based on Data Aggregation Shenyang LigongUniversity Shenyang China 2015
[10] J P Shao Research on Key Energy-Efficient Routing Tech-nology of WSN Based on Cluster Shenyang Ligong UniversityShenyang China 2015
[11] V K Arora V Sharma and M Sachdeva ldquoA survey onLEACH and otherrsquos routing protocols in wireless sensornetworkrdquo Optik vol 127 no 16 pp 6590ndash6600 2016
[12] W B Heinzelman A P Chandrakasan and H BalakrishnanldquoAn application-specific protocol architecture for wirelessmicrosensor networksrdquo IEEE Transactions on WirelessCommunications vol 1 no 4 pp 660ndash670 2002
[13] S Al-Sodairi and R Ouni ldquoReliable and energy-efficientmulti-hop LEACH-based clustering protocol for wirelesssensor networksrdquo Sustainable Computing Informatics andSystems vol 20 pp 1ndash13 2018
[14] O Younis and S Fahmy ldquoHEED a hybrid energy-efficientdistributed clustering approach for ad hoc sensor networksrdquo
IEEE Transactions on Mobile Computing vol 3 no 4pp 366ndash379 2004
[15] B B Chen and Y L Shi ldquoWSN routing protocol based oncluster heads selection in regionsrdquo Computer Engineeringvol 37 no 19 pp 96ndash98 2011
[16] P Azada ldquoCluster head selection in wireless sensor networksunder fuzzy environmentrdquo ISRN Sensor Networks vol 2013Article ID 909086 8 pages 2013
[17] S Soro and W B Heinzelman ldquoCluster head election tech-niques for coverage preservation in wireless sensor networksrdquoAd Hoc Networks vol 7 no 5 pp 955ndash972 2009
[18] A akkar ldquoDEAL distance and energy based advancedleach protocolrdquo in Proceedings of the International Conferenceon Information and Communication Technology for IntelligentSystems pp 370ndash376 Ahmedabad India March 2017
[19] T Y Chang W N Liu Y Zhang and H Y Li ldquoOptimizedLEACH protocol based on distance and energy of clusterheadrdquo Journal of Hebei University (Natural Science Edition)vol 39 no 2 pp 194ndash200 2019
[20] P Mehra M Doja and B Alam ldquoStability enhancement inLEACH (SE-LEACH) for homogeneousWSNrdquo EAI EndorsedTransactions on Scalable Information Systems vol 6 no 20pp 1ndash9 2019
[21] G Smaragdakis I Matta and A Bestavros ldquoSEP a stableelection protocol for clustered heterogeneous wireless sensornetworksrdquo in Proceedings of the Second InternationalWorkshop on Sensor and Actor Network Protocols and Ap-plications (SANPA 2004) pp 1ndash11 Boston MA USA June2004
[22] F S Hu and Q Xiao ldquoMulti-hop routing algorithm of energy-balancing based on LEACHrdquo Journal of Chinese ComputerSystems vol 35 no 1 pp 72ndash75 2014
[23] C F Li M Ye G H Chen and J Wu ldquoAn energy-efficientunequal clustering mechanism for wireless sensor networksrdquoin Proceedings of the IEEE International Conference on MobileAdhoc and Sensor Systems Conference p 604 WashingtonDC USA November 2005
[24] E Alnawafa I Marghescu and MHT ldquoMulti-hop techniquefor the improvement of leach protocolrdquo in Proceedings of the2016 15th RoEduNet Conference Networking in Education andResearch pp 1ndash5 Bucharest Romania September 2016
[25] E Alnawafa and I Marghescu ldquoIMHT improved MHT-LEACH protocol for wireless sensor networksrdquo in Proceedingsof the 2017 8th International Conference on Information andCommunication Systems (ICICS) pp 246ndash251 Irbid JordanApril 2017
[26] J Y Huo Z Zhang and C Tao ldquoUsing IPv6 address ad-vantage to build Network Node of Field observation In-struments in cold and arid areasrdquo China Education Networkno 5 pp 45-46 2018
[27] L Mateu and F Moll ldquoReview of energy harvesting tech-niques and applications for microelectronicsrdquo in Proceedingsof the International Society for Optical Engineering pp 359ndash373 Bellingham WA USA October 2005
[28] G Wang and R Y Wang ldquoRouting algorithm based oncluster-head optimization for self-energized wireless sensornetworkrdquo Journal of Computer Applications vol 38 no 334pp 201ndash216 2018
[29] X P Fan X Yang S Q Liu and Z H Qu ldquoClusteringrouting algorithm for wireless sensor networks with powerharvestingrdquo Computer Engineering vol 39 no 11 pp 126ndash134 2008
18 Journal of Electrical and Computer Engineering
[30] C H Zhang ldquoStudy on the energy heterogeneous clusteringrouting protocol for wireless sensor networksrdquo Science ampTechnology Vision no 13 pp 71+164ndash165 2012
[31] T Liu and F Li ldquoPower-efficient clustering routing protocolbased on applications in wireless sensor networkrdquo in Pro-ceedings of the International Conference on Wireless Com-munications IEEE Press Melbourne Australia September2009
Journal of Electrical and Computer Engineering 19
e BS is located outside the monitoring area it hassufficient energy resources and each node knows thelocation of the BS
42 Energy Model Energy consumption is an importantcriterion to evaluate the performance of a routing protocole network life mainly depends on the energy consumed indata sending and data receiving Meanwhile the energyconsumed by the CH when using the fusion technologyshould be considered and the energy consumption of thenode in the process of calculation and storage should beneglected LEACH protocol uses first-order wireless mode inWSNs so it adopts a simple energy consumptionmodel [12]e model defines that the energy consumed by each l bitdata sent by the wireless circuit is
ETx(l d) ETxminuselec(l d) + ETxminusamp(l d)
lEelec + lEfsd
2 dlt d0
lEelec + lEmpd4 dge d0
⎧⎨
⎩
(9)
When receiving information the energy consumed bythe wireless circuit receiving l bit data is
ERx(l d) ERxminuselec(l d) lEelec (10)
e energy consumed by data fusion is
EGx lEgather (11)
In equations (9)-(10) d represents the distance betweenthe sending node and the receiving node and Eelec representsthe energy consumed for each bit of data sent or received Inequation (9) Efsd
2 is the energy consumed by the free spacemodel for each l bit of data amplification and Empd4 is theenergy consumed by the multipath attenuation model foreach l bit of data amplification Obviously when the distancebetween nodes becomes more extensive the energy con-sumption increases exponentially erefore if you want toreduce the energy consumption of data transmission youmust reduce the distance between nodes e Egather inequation (11) is expressed as the energy consumed by datafusion for each processing of 1 bit the d0 in equation (9) is athreshold which is determined by the equation (12) and isdefined as 87m in this paper
d0
Efs
Emp
1113971
(12)
5 Simulation Experiments and Analysis
51 Experimental Setting In order to analyze the perfor-mance of the FOI-LEACH protocol this paper conductssimulation experiments onMATLAB simulation platform tocompare it with the original LEACH protocol [4] SEPprotocol [21] and PECRP protocol [31] e simulationexperiments were carried out under the monitoring area of100mtimes 100m and the BS is located outside the monitoringarea with the coordinate of (150 50) As shown in Figure 4
the initial node distribution map distinguishes the nodes ineach zone by color in which red represents the nodes in zoneA blue represents the nodes in zone B and the greenrepresents the nodes in zone C And ldquordquo means the normalnode ldquo+rdquo means the advanced node and ldquotimesrdquo means BS
In the self-energy experiment all the surviving nodes inthe network are replenished with energy once every fiverounds until the simulation end e recharge energy isdistributed randomly to all remaining surviving nodes in thenetwork e total energy of the first replenishment is set to035 J In the later replenishment in order to prevent thenodes in the network from dying when there are too fewnodes We set the attenuation factor alpha to 09 that is theenergy replenishment to all the nodes in the network is 09times of the previous timee initial energy and topology ofall the experimental networks were set to the same envi-ronment When all the nodes in the network die the net-work is considered to be invalid Experiments proved thatthe network works best when the parameters are set to thefollowing valuesm is set to 01 a is set to 2 α is set to 03 andβ is set to 07e range of optimal CH number is [1 14] and10 is taken in this paper the probability of optimal CHnumber is popt 0 1 e three-partition system shown inFigure 2 was adopted in the routing protocol e specificparameters of the simulation experiments are listed inTable 1
52 Determination of the Partitioning Scheme e FOI-LEACH protocol proposed in this paper is based on theimprovement of the LEACH protocol In the initial stage ofnode deployment the distance between the node and the BSis obtained according to the signal strength of the BS re-ceived by the node en the monitoring area is partitionedaccording to the distance To determine the optimal parti-tioning scheme in the FOI-LEACH protocol we proposedthe following five schemes for the protocol and tested themin the partitioning experiment
Scheme 1 e monitoring area is divided into twozones A and B and the zone SA of A is equal to thezone SB of B as shown in Figure 5 (partitioning scheme1) e CH in zone B chooses the CH in zone A closest
0 50 100 1500
10
20
30
40
50
60
70
80
90
100
Advanced node
Normal node
BS
Figure 4 Distribution diagram of initial nodes
8 Journal of Electrical and Computer Engineering
to it for forwarding data and the CHs in zone Acommunicates directly with the BSScheme 2 As shown in Figure 5 (partitioning scheme2) the monitoring area is divided into two zones A andB and the SA of zone A is smaller than the area SB ofzone BScheme 3 e monitoring area is divided into threezones A B and C and the area SA of zone A is equalto the area SB of zone B and smaller than the area SC
of zone C as shown in Figure 5 (partitioning scheme3)Scheme 4 e monitoring area is divided into threezones A B and C and the area SA of zone A is smallerthan the area SB of zone B and smaller than the area SC
of zone C as shown in Figure 5 (partitioning scheme 4)Scheme 5 e monitoring area is divided into threezones A B and C and the area SA of zone A is equal tothe area SC of zone C and smaller than the area SB ofzone B as shown in Figure 5 (partitioning scheme 5)
e survival nodes and the average residual energy ineach round of the five partitioning schemes are drawn inFigures 6 and 7 respectively Based on the experimentalanalysis it can be found that Scheme 3 indicated as a redcurve in the figures has a better performance In scheme 3ie SA SB lt SC the first dead node appears in the 587thround which is later than other schemes that is thestability period is more extended than other schemes eaverage residual energy consumption rate of nodes is alsolower than that of other schemes is is because zones Aand B need to bear more forwarding energy so when thesetwo zones are smaller than zone C the network energyconsumption is more balanced erefore we adopted thepartitioning method of scheme 3 to carry out the simu-lation experiments
53 Analysis of Parameters In equation (4) parameters αand β determine the difference in cluster size erefore therelationship between these two parameters and network lifewas observed by taking α from 0 to 1 and β from 1 to 0 eresults of parameters analysis are shown in Figure 8 whichalso proves the rationality of our unequal clusteringmechanism When parameter α increases from 0 to 1 theeffect of the unequal clustering method is noticeableHowever the impact of parameter β on the network shouldalso be considered If the value of α is too large the lifetimeof the system will be shortened It is because too manyclusters will be generated near the BS and each cluster sendspackets to the BS which results in the waste of energyerefore it needs to determine the optimal values forparameters α and β In this experiment we can concludefrom Figure 8 that when α 0 3 and β 0 7 the death timeof the first node is later and the network is more stable
54 Experimental Comparison Analysis is paper mainlyevaluates the performance of the observation instrumentnetwork routing protocol with and without energy supplythrough the following evaluation elements
Network lifetime the network lifetime is measured bythe survival rate of the whole network nodes whichgenerally represents a certain proportion of the energyloss of the network node In this paper we took thedeath time interval from the beginning of the networkto the last surviving node as the lifetime of the networkEnergy consumption rate it usually refers to the av-erage energy consumption of a node sending or re-ceiving a byte of data It is essential to evaluate theperformance of routing algorithmsStability the stability of the field instruments obser-vation network was evaluated from two aspects thetime interval from the beginning of the network to thedeath of the first node and the number of CHsNetwork throughput the indicator to measure theefficiency of the network which is usually judged by thetotal number of packets sent to BS and the total numberof packets sent to CH
541 Experiments without Energy Supply
(1) Network Lifetime Figure 9 shows the number of sur-viving nodes in the network when the network runs for 2100rounds without being self-energized According to thestatistics of the number of rounds of death node in Table 2the network failure of the LEACH protocol occurs at round276 the network of SEP protocol expires at 462 rounds andnetwork failure of the PECRP protocol at round 438However the FOI-LEACH protocol was not expired untilround 2042 which significantly increased the networksurvival time It is because the FOI-LEACH protocol con-siders such factors as energy and distance in stages of CHelection cluster formation and intercluster communication
Table 1 Parameters in the simulation experiments
Parameter ValueTotal number of nodes N 100Network area (m) 100times100Coordinates of BS (m) (150 50)Data packet size L (bit) 4000Initial energy of normal node (J) 01Initial energy of advanced node (J) 03Energy consumption of transmitting circuit ETX (nJbit) 50
Energy consumption of receiving circuit ERX (nJbit) 50Free space model energy Efs (pJbitm
2) 10Multipath attenuation model energy Emp (pJbitm2) 00013Energy consumption of data fusion EDA (nJbit) 5Probability of the optimal number of CHs popt 01Maximum cluster radius in zone A RcA (m) 125Maximum cluster radius in zone B RcB (m) 125Maximum cluster radius in zone C RcC (m) 25Attenuation factor alpha 09M 01A 2α 03β 07
Journal of Electrical and Computer Engineering 9
AB
(a)
AB
(b)
ABC
(c)
ABC
(d)
ABC
(e)
Figure 5 Partitioning scheme (a) Partitioning scheme 1 SaltSb (b) Partitioning scheme 2 SaSb (c) Partitioning scheme 1 SaSbltSc (d)Partitioning scheme 1 SaltSbltSc (e) Partitioning scheme 1 SaScltSb
AeqBAsBAeqBsC
AsBsCAeqCsB
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
Figure 6 Comparison of active nodes in each round
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
002
004
006
008
01
012
Ave
rage
resid
ual e
nerg
y
AeqBAsBAeqBsC
AsBsCAeqCsB
Figure 7 Comparison of average residual energy in each round
10 Journal of Electrical and Computer Engineering
(2) Average Residual Energy and Energy Dissipation RateFigure 10 shows the graph of the average residual energy ofthe network running 2100 rounds without being self-en-ergized Combined with the network average residual en-ergy which is shown in Table 3 it can be drawn that the FOI-LEACH protocol is more slowly energy consumed Besidesit can be seen from Figure 10 that the energy consumption
rate of the improved network is significantly reduced toachieve the purpose of delaying energy consumption andextending network life
(3) Stability e stability of networking was evaluated fromtwo aspects First it can be seen from Figure 9 that the FOI-LEACH protocol significantly extends the death time of the
Self-energized
400
420
440
460
480
500
520
540
Dea
th ti
me o
f the
firs
t nod
e
01 02 03 04 05 06 07 08 09 10α
Figure 8 Impact of parameters α and β on the network lifetime
LEACHSEP
PECRPImproved protocol
400
160060
0
2000
1000
1200
140020
0
1800
21000
800
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
Figure 9 Comparison of live nodes in each round without power supply
Table 2 Statistics number of rounds of dead nodes of the four protocols without power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 135 160 204 276SEP 174 191 226 462PECRP 338 374 412 438FOI-LEACH 481 684 1272 2042
Journal of Electrical and Computer Engineering 11
first node For the LEACH protocol the nodes began to dieat round 135 SEP protocol at round 174 and PECRPprotocol at round 338 Because the energy factor is takeninto account in selecting the CH energy and distance factorsare taken into account in clustering and the adopted zone-based autonomous multihop communication model mini-mizes the Hello control package the nodes die at round 481for the FOI-LEACH protocol As a result the FOI-LEACHprotocol has better performance than other protocols
Figure 11 shows the distribution of the number ofclusters of the four protocols without energy supply simulatedfor 10 rounds of random elections in which Figure 11(a)represents the statistics number of CHs in each zone of theFOI-LEACH protocol and Figure 11(b) represents the sta-tistics number of CHs in the whole network of FOI-LEACHprotocol Figures 11(c)ndash11(e) represent the statistics numberof CHs of LEACH SEP and PECRP protocols respectively Itcan be seen that the number of CHs of FOI-LEACH protocolis more stable than that of LEACH SEP and PECRP BecauseLEACH and SEP randomly select CHs the number of CHsproduced was unstable e FOI-LEACH protocol formsclusters by selecting CHs with a competitive radius and thenumber of CHs is relatively stable
(4) Network (roughput Figure 12 shows that in theLEACH protocol SEP protocol PECRP protocol and ourproposed FOI-LEACH protocol the total number of packets
sent to BS is approximately 900 2580 2980 and 11140respectively Moreover Figure 13 shows that in the LEACHprotocol SEP protocol PECRP protocol and FOI-LEACHprotocol the total number of packages sent to CHs is ap-proximately 7500 21000 38200 and 119000 respectively Itis because the proposed scheme has a high network lifetimethe total number of packets sent to BS and CHs is muchhigher than other protocols
542 Experiments with Energy Supply
(1) Network Lifetime Figure 14 shows the number of sur-viving nodes in the network when the network runs for 2300rounds self-energized According to the statistics of deathnodes in Table 4 we can find that the network lifetime of thefour protocols all has been extended e network failure ofthe LEACH protocol occurred at round 341 the network ofthe SEP protocol expires at round 665 and network failure ofPECRP protocol at round 530 and the FOI-LEACH pro-tocol was not expired until round 2246 which significantlyincreased the network survival time It is demonstrated thatthe improved schemes can work well in both the environ-ments with or without power supply
(2) Average Residual Energy and Energy Dissipation RateFigure 15 shows the graph of the average residual energy ofthe network running 2300 rounds self-energized Combinedwith the network average residual energy which shown inTable 5 it can be drawn that the FOI-LEACH protocol ismore slowly energy consumed Besides it can be seen fromFigure 15 that the energy consumption rate of the improvednetwork is significantly reduced to achieve the purpose ofdelaying energy consumption and extending network life
(3) Stability For the stability of field instruments net-working it can be seen from Figure 14 that the FOI-LEACHprotocol significantly extends the death time of the first
1800
2000
1000
1600
210060
0
200
8000
120040
0
1400
Number of rounds
0
002
004
006
008
01
012
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 10 Comparison of average residual energy in each round without power supply
Table 3 Statistics of the average residual energy (J) of nodes of thefour protocols without power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0075 0007 0 0SEP 0094 002 0 0PECRP 0088 0053 0 0FOI-LEACH 0113 0092 0043 152times10minus5
12 Journal of Electrical and Computer Engineering
ABC
0
1
2
3
4
5
6
7Co
mpa
rison
of C
Hs i
n ea
ch re
gion
2 3 4 5 6 7 8 9 101Number of rounds
(a)
0
2
4
6
8
10
12
14
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(d)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 11 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol without power supply
Journal of Electrical and Computer Engineering 13
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
2000
4000
6000
8000
10000
12000
Pack
ets t
o BS
LEACHSEP
PECRPImproved protocol
Figure 12 Comparison of packets sent to BS from CHs without power supply
times104
200
400
600
800
1000
1200
2000
1800
21000
1400
1600
Number of rounds
0
2
4
6
8
10
12
Pack
ets t
o CH
LEACHSEP
PECRPImproved protocol
Figure 13 Comparison of packets sent to CHs from member nodes without power supply
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
LEACHSEP
PECRPImproved protocol
Figure 14 Comparison of live nodes in each round with power supply
14 Journal of Electrical and Computer Engineering
Table 4 Statistics number of rounds of dead nodes of the four protocols with power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 177 204 232 341SEP 185 210 264 665PECRP 392 430 493 530FOI-LEACH 555 716 1238 2246
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
002
004
006
008
01
012
014
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 15 Comparison of average residual energy in each round with power supply
Table 5 Statistics of the average residual energy (J) of nodes of the four protocols with power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0086 0018 0 0SEP 0105 0036 0001 0PECRP 0099 007 0 0FOI-LEACH 0124 0109 0062 0001
0
1
2
3
4
5
6
7
8
Com
paris
on o
f CH
s in
each
regi
on
2 3 4 5 6 7 8 9 101Number of rounds
ABC
(a)
0
2
4
6
8
10
12
1415
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
Figure 16 Continued
Journal of Electrical and Computer Engineering 15
0
2
4
6
8
10
12
14
16N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14
16
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(d)
0
2
4
6
8
10
12
14
16
18
20
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 16 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol with power supply
0
2000
4000
6000
8000
10000
12000
14000
Pack
ets t
o BS
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 17 Comparison of packets sent to BS from CHs with power supply
16 Journal of Electrical and Computer Engineering
node e supplied energy promotes the extension of thenetwork lifetime and the stability of the networking for thefour protocols in varying degrees For the LEACH protocolthe node began to die at round 177 SEP protocol at round185 PECRP protocol at round 392 and round 555 for theimproved FOI-LEACH protocol
e distributions of the number of clusters in the fourprotocols with energy supply simulated for 10 rounds ofrandom elections are shown in Figure 16 Like the previousfigures Figure 16(a) represents the statistics number of CHsof each zone of FOI-LEACH protocol Figures 16(b)ndash16(e)represent the statistics number of CHs of FOI-LEACHprotocol LEACH protocol SEP protocol and PECRPprotocol respectively Due to the efficient schemes of CHselecting and clustering the FOI-LEACH protocol showssignificantly better performance than the other threeprotocols
(4) Network (roughput In the environment of self-energyas shown in Figure 17 the total number of packets sent toBS of the LEACH protocol SEP protocol PECRP protocoland the proposed FOI-LEACH protocol is approximately2428 3080 3746 and 13265 respectively Moreover inFigure 18 the total number of packages sent to CHs of theLEACH protocol SEP protocol PECRP protocol andFOI-LEACH protocol is approximately 21400 2430044000 and 123200 respectively We can find that the totalnumber of packets sent by our protocol to BS and CHs ismuch higher than the other protocols which also dem-onstrated that the proposed protocol has a better networkthroughout
6 Conclusions
According to the characteristics of field observation in-strument networking an improved protocol FOI-LEACHbased on LEACH protocol was proposed in this paper Byconsidering the energy factor in the CH election threshold
and referring to the SEP protocol to set up two kinds ofnodes with different initial energies which are calledadvanced nodes and normal nodes the network model offield observation instruments has been established Inaddition to solve the problem that the LEACH protocolconsumes much energy during transmission and results inuneven energy consumption for the direct and long-distance transmission the improved protocol adopted the3 zones of partitioning mechanism and the multihoptransmission mechanism to alleviate and avoid the ldquohotspotrdquo problems Furthermore energy supplies were addedto the nodes in A and B zones that are responsible formore energy transmission so as to balance the energyconsumption of the network and prolong the networklifetime In the simulation experiments we compared theperformance of the FOI-LEACH protocol with theLEACH SEP and PECRP protocols in two cases with orwithout energy supply Comparing performance indica-tors of network lifetime energy consumption rate sta-bility and network throughput the proposed FOI-LEACH protocol can slow down the death of nodes andthe energy consumption rate obviously and shows asignificantly better performance than other three proto-cols e experimental results demonstrated that the FOI-LEACH protocol could balance network energy con-sumption and alleviate the ldquohot spotrdquo problem to extendthe lifetime of network nodes in the field observationinstruments network e future work is to implementand port the improved protocol to the hardware of net-working node we designed and developed previously andtest and verify the feasibility and stability of the protocolin the actual situation
Data Availability
e initial nodes are generated randomly in the networkand there are no observation data used in the simulationexperiments
0
20000
40000
60000
80000
100000
120000
140000
Pack
ets t
o CH
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 18 Comparison of packets sent to CHs from nodes with power supply
Journal of Electrical and Computer Engineering 17
Conflicts of Interest
e authors declare that there are no conflicts of interest
Acknowledgments
is work was supported by the National Nature ScienceFoundation of China (Grant no 61862038) the LanzhouTalent Innovation and Entrepreneurship Technology PlanProject (no 2019-RC-14) and the Foundation of a HundredYouth Talents Training Program of Lanzhou JiaotongUniversity
References
[1] J Y Huo Z N Ren and Y R Yang A Kind of InstrumentNetwork Node Equipment and Monitoring System ChinesePatents Beijing China 2017
[2] J Y Huo Key Technology and Application Research ofE-Science Virtual Joint Observation System for Geoscience inCold and Dry Regions University of Chinese Academy ofSciences Beijing China 2012
[3] I F Akyildiz W L Weilian Su Y Sankarasubramaniam andE Cayirci ldquoA survey on sensor networksrdquo IEEE Communi-cations Magazine vol 40 no 8 pp 102ndash114 2002
[4] W R Heinzelman A Chandrakasan and H BalakrishnanldquoEnergy-efficient communication protocol for wirelessmicrosensor networksrdquo in Proceedings of the 33rd HawaiiIntentional Conference on System Sciences Maui HI USAJanuary 2000
[5] D Mehta and S Saxena ldquoA comparative analysis of energyefficient hierarchical routing protocols for wireless sensornetworksrdquo in Proceedings of the 2018 4th InternationalConference on Computing Sciences (ICCS) pp 53ndash58Jalandhar India August 2018
[6] C Karlof and D Wagner ldquoSecure routing in wireless sensornetworks attacks and countermeasuresrdquo Ad Hoc Networksvol 1 2003
[7] L B Oliveira A Ferreira M A Vilaca et al ldquoSecLEACH-onthe security of clustered sensor networksrdquo Signal Processingvol 87 2007
[8] Y Y Gu GW Bai and J J Tao ldquoAZM-LEACH autonomouszone-based multi-hop routing protocol in WSNsrdquo ComputerEngineering and Applications vol 47 no 20 pp 58ndash61 2011
[9] L XWang Research on Routing Technology ofWireless SensorNetworks Based on Data Aggregation Shenyang LigongUniversity Shenyang China 2015
[10] J P Shao Research on Key Energy-Efficient Routing Tech-nology of WSN Based on Cluster Shenyang Ligong UniversityShenyang China 2015
[11] V K Arora V Sharma and M Sachdeva ldquoA survey onLEACH and otherrsquos routing protocols in wireless sensornetworkrdquo Optik vol 127 no 16 pp 6590ndash6600 2016
[12] W B Heinzelman A P Chandrakasan and H BalakrishnanldquoAn application-specific protocol architecture for wirelessmicrosensor networksrdquo IEEE Transactions on WirelessCommunications vol 1 no 4 pp 660ndash670 2002
[13] S Al-Sodairi and R Ouni ldquoReliable and energy-efficientmulti-hop LEACH-based clustering protocol for wirelesssensor networksrdquo Sustainable Computing Informatics andSystems vol 20 pp 1ndash13 2018
[14] O Younis and S Fahmy ldquoHEED a hybrid energy-efficientdistributed clustering approach for ad hoc sensor networksrdquo
IEEE Transactions on Mobile Computing vol 3 no 4pp 366ndash379 2004
[15] B B Chen and Y L Shi ldquoWSN routing protocol based oncluster heads selection in regionsrdquo Computer Engineeringvol 37 no 19 pp 96ndash98 2011
[16] P Azada ldquoCluster head selection in wireless sensor networksunder fuzzy environmentrdquo ISRN Sensor Networks vol 2013Article ID 909086 8 pages 2013
[17] S Soro and W B Heinzelman ldquoCluster head election tech-niques for coverage preservation in wireless sensor networksrdquoAd Hoc Networks vol 7 no 5 pp 955ndash972 2009
[18] A akkar ldquoDEAL distance and energy based advancedleach protocolrdquo in Proceedings of the International Conferenceon Information and Communication Technology for IntelligentSystems pp 370ndash376 Ahmedabad India March 2017
[19] T Y Chang W N Liu Y Zhang and H Y Li ldquoOptimizedLEACH protocol based on distance and energy of clusterheadrdquo Journal of Hebei University (Natural Science Edition)vol 39 no 2 pp 194ndash200 2019
[20] P Mehra M Doja and B Alam ldquoStability enhancement inLEACH (SE-LEACH) for homogeneousWSNrdquo EAI EndorsedTransactions on Scalable Information Systems vol 6 no 20pp 1ndash9 2019
[21] G Smaragdakis I Matta and A Bestavros ldquoSEP a stableelection protocol for clustered heterogeneous wireless sensornetworksrdquo in Proceedings of the Second InternationalWorkshop on Sensor and Actor Network Protocols and Ap-plications (SANPA 2004) pp 1ndash11 Boston MA USA June2004
[22] F S Hu and Q Xiao ldquoMulti-hop routing algorithm of energy-balancing based on LEACHrdquo Journal of Chinese ComputerSystems vol 35 no 1 pp 72ndash75 2014
[23] C F Li M Ye G H Chen and J Wu ldquoAn energy-efficientunequal clustering mechanism for wireless sensor networksrdquoin Proceedings of the IEEE International Conference on MobileAdhoc and Sensor Systems Conference p 604 WashingtonDC USA November 2005
[24] E Alnawafa I Marghescu and MHT ldquoMulti-hop techniquefor the improvement of leach protocolrdquo in Proceedings of the2016 15th RoEduNet Conference Networking in Education andResearch pp 1ndash5 Bucharest Romania September 2016
[25] E Alnawafa and I Marghescu ldquoIMHT improved MHT-LEACH protocol for wireless sensor networksrdquo in Proceedingsof the 2017 8th International Conference on Information andCommunication Systems (ICICS) pp 246ndash251 Irbid JordanApril 2017
[26] J Y Huo Z Zhang and C Tao ldquoUsing IPv6 address ad-vantage to build Network Node of Field observation In-struments in cold and arid areasrdquo China Education Networkno 5 pp 45-46 2018
[27] L Mateu and F Moll ldquoReview of energy harvesting tech-niques and applications for microelectronicsrdquo in Proceedingsof the International Society for Optical Engineering pp 359ndash373 Bellingham WA USA October 2005
[28] G Wang and R Y Wang ldquoRouting algorithm based oncluster-head optimization for self-energized wireless sensornetworkrdquo Journal of Computer Applications vol 38 no 334pp 201ndash216 2018
[29] X P Fan X Yang S Q Liu and Z H Qu ldquoClusteringrouting algorithm for wireless sensor networks with powerharvestingrdquo Computer Engineering vol 39 no 11 pp 126ndash134 2008
18 Journal of Electrical and Computer Engineering
[30] C H Zhang ldquoStudy on the energy heterogeneous clusteringrouting protocol for wireless sensor networksrdquo Science ampTechnology Vision no 13 pp 71+164ndash165 2012
[31] T Liu and F Li ldquoPower-efficient clustering routing protocolbased on applications in wireless sensor networkrdquo in Pro-ceedings of the International Conference on Wireless Com-munications IEEE Press Melbourne Australia September2009
Journal of Electrical and Computer Engineering 19
to it for forwarding data and the CHs in zone Acommunicates directly with the BSScheme 2 As shown in Figure 5 (partitioning scheme2) the monitoring area is divided into two zones A andB and the SA of zone A is smaller than the area SB ofzone BScheme 3 e monitoring area is divided into threezones A B and C and the area SA of zone A is equalto the area SB of zone B and smaller than the area SC
of zone C as shown in Figure 5 (partitioning scheme3)Scheme 4 e monitoring area is divided into threezones A B and C and the area SA of zone A is smallerthan the area SB of zone B and smaller than the area SC
of zone C as shown in Figure 5 (partitioning scheme 4)Scheme 5 e monitoring area is divided into threezones A B and C and the area SA of zone A is equal tothe area SC of zone C and smaller than the area SB ofzone B as shown in Figure 5 (partitioning scheme 5)
e survival nodes and the average residual energy ineach round of the five partitioning schemes are drawn inFigures 6 and 7 respectively Based on the experimentalanalysis it can be found that Scheme 3 indicated as a redcurve in the figures has a better performance In scheme 3ie SA SB lt SC the first dead node appears in the 587thround which is later than other schemes that is thestability period is more extended than other schemes eaverage residual energy consumption rate of nodes is alsolower than that of other schemes is is because zones Aand B need to bear more forwarding energy so when thesetwo zones are smaller than zone C the network energyconsumption is more balanced erefore we adopted thepartitioning method of scheme 3 to carry out the simu-lation experiments
53 Analysis of Parameters In equation (4) parameters αand β determine the difference in cluster size erefore therelationship between these two parameters and network lifewas observed by taking α from 0 to 1 and β from 1 to 0 eresults of parameters analysis are shown in Figure 8 whichalso proves the rationality of our unequal clusteringmechanism When parameter α increases from 0 to 1 theeffect of the unequal clustering method is noticeableHowever the impact of parameter β on the network shouldalso be considered If the value of α is too large the lifetimeof the system will be shortened It is because too manyclusters will be generated near the BS and each cluster sendspackets to the BS which results in the waste of energyerefore it needs to determine the optimal values forparameters α and β In this experiment we can concludefrom Figure 8 that when α 0 3 and β 0 7 the death timeof the first node is later and the network is more stable
54 Experimental Comparison Analysis is paper mainlyevaluates the performance of the observation instrumentnetwork routing protocol with and without energy supplythrough the following evaluation elements
Network lifetime the network lifetime is measured bythe survival rate of the whole network nodes whichgenerally represents a certain proportion of the energyloss of the network node In this paper we took thedeath time interval from the beginning of the networkto the last surviving node as the lifetime of the networkEnergy consumption rate it usually refers to the av-erage energy consumption of a node sending or re-ceiving a byte of data It is essential to evaluate theperformance of routing algorithmsStability the stability of the field instruments obser-vation network was evaluated from two aspects thetime interval from the beginning of the network to thedeath of the first node and the number of CHsNetwork throughput the indicator to measure theefficiency of the network which is usually judged by thetotal number of packets sent to BS and the total numberof packets sent to CH
541 Experiments without Energy Supply
(1) Network Lifetime Figure 9 shows the number of sur-viving nodes in the network when the network runs for 2100rounds without being self-energized According to thestatistics of the number of rounds of death node in Table 2the network failure of the LEACH protocol occurs at round276 the network of SEP protocol expires at 462 rounds andnetwork failure of the PECRP protocol at round 438However the FOI-LEACH protocol was not expired untilround 2042 which significantly increased the networksurvival time It is because the FOI-LEACH protocol con-siders such factors as energy and distance in stages of CHelection cluster formation and intercluster communication
Table 1 Parameters in the simulation experiments
Parameter ValueTotal number of nodes N 100Network area (m) 100times100Coordinates of BS (m) (150 50)Data packet size L (bit) 4000Initial energy of normal node (J) 01Initial energy of advanced node (J) 03Energy consumption of transmitting circuit ETX (nJbit) 50
Energy consumption of receiving circuit ERX (nJbit) 50Free space model energy Efs (pJbitm
2) 10Multipath attenuation model energy Emp (pJbitm2) 00013Energy consumption of data fusion EDA (nJbit) 5Probability of the optimal number of CHs popt 01Maximum cluster radius in zone A RcA (m) 125Maximum cluster radius in zone B RcB (m) 125Maximum cluster radius in zone C RcC (m) 25Attenuation factor alpha 09M 01A 2α 03β 07
Journal of Electrical and Computer Engineering 9
AB
(a)
AB
(b)
ABC
(c)
ABC
(d)
ABC
(e)
Figure 5 Partitioning scheme (a) Partitioning scheme 1 SaltSb (b) Partitioning scheme 2 SaSb (c) Partitioning scheme 1 SaSbltSc (d)Partitioning scheme 1 SaltSbltSc (e) Partitioning scheme 1 SaScltSb
AeqBAsBAeqBsC
AsBsCAeqCsB
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
Figure 6 Comparison of active nodes in each round
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
002
004
006
008
01
012
Ave
rage
resid
ual e
nerg
y
AeqBAsBAeqBsC
AsBsCAeqCsB
Figure 7 Comparison of average residual energy in each round
10 Journal of Electrical and Computer Engineering
(2) Average Residual Energy and Energy Dissipation RateFigure 10 shows the graph of the average residual energy ofthe network running 2100 rounds without being self-en-ergized Combined with the network average residual en-ergy which is shown in Table 3 it can be drawn that the FOI-LEACH protocol is more slowly energy consumed Besidesit can be seen from Figure 10 that the energy consumption
rate of the improved network is significantly reduced toachieve the purpose of delaying energy consumption andextending network life
(3) Stability e stability of networking was evaluated fromtwo aspects First it can be seen from Figure 9 that the FOI-LEACH protocol significantly extends the death time of the
Self-energized
400
420
440
460
480
500
520
540
Dea
th ti
me o
f the
firs
t nod
e
01 02 03 04 05 06 07 08 09 10α
Figure 8 Impact of parameters α and β on the network lifetime
LEACHSEP
PECRPImproved protocol
400
160060
0
2000
1000
1200
140020
0
1800
21000
800
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
Figure 9 Comparison of live nodes in each round without power supply
Table 2 Statistics number of rounds of dead nodes of the four protocols without power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 135 160 204 276SEP 174 191 226 462PECRP 338 374 412 438FOI-LEACH 481 684 1272 2042
Journal of Electrical and Computer Engineering 11
first node For the LEACH protocol the nodes began to dieat round 135 SEP protocol at round 174 and PECRPprotocol at round 338 Because the energy factor is takeninto account in selecting the CH energy and distance factorsare taken into account in clustering and the adopted zone-based autonomous multihop communication model mini-mizes the Hello control package the nodes die at round 481for the FOI-LEACH protocol As a result the FOI-LEACHprotocol has better performance than other protocols
Figure 11 shows the distribution of the number ofclusters of the four protocols without energy supply simulatedfor 10 rounds of random elections in which Figure 11(a)represents the statistics number of CHs in each zone of theFOI-LEACH protocol and Figure 11(b) represents the sta-tistics number of CHs in the whole network of FOI-LEACHprotocol Figures 11(c)ndash11(e) represent the statistics numberof CHs of LEACH SEP and PECRP protocols respectively Itcan be seen that the number of CHs of FOI-LEACH protocolis more stable than that of LEACH SEP and PECRP BecauseLEACH and SEP randomly select CHs the number of CHsproduced was unstable e FOI-LEACH protocol formsclusters by selecting CHs with a competitive radius and thenumber of CHs is relatively stable
(4) Network (roughput Figure 12 shows that in theLEACH protocol SEP protocol PECRP protocol and ourproposed FOI-LEACH protocol the total number of packets
sent to BS is approximately 900 2580 2980 and 11140respectively Moreover Figure 13 shows that in the LEACHprotocol SEP protocol PECRP protocol and FOI-LEACHprotocol the total number of packages sent to CHs is ap-proximately 7500 21000 38200 and 119000 respectively Itis because the proposed scheme has a high network lifetimethe total number of packets sent to BS and CHs is muchhigher than other protocols
542 Experiments with Energy Supply
(1) Network Lifetime Figure 14 shows the number of sur-viving nodes in the network when the network runs for 2300rounds self-energized According to the statistics of deathnodes in Table 4 we can find that the network lifetime of thefour protocols all has been extended e network failure ofthe LEACH protocol occurred at round 341 the network ofthe SEP protocol expires at round 665 and network failure ofPECRP protocol at round 530 and the FOI-LEACH pro-tocol was not expired until round 2246 which significantlyincreased the network survival time It is demonstrated thatthe improved schemes can work well in both the environ-ments with or without power supply
(2) Average Residual Energy and Energy Dissipation RateFigure 15 shows the graph of the average residual energy ofthe network running 2300 rounds self-energized Combinedwith the network average residual energy which shown inTable 5 it can be drawn that the FOI-LEACH protocol ismore slowly energy consumed Besides it can be seen fromFigure 15 that the energy consumption rate of the improvednetwork is significantly reduced to achieve the purpose ofdelaying energy consumption and extending network life
(3) Stability For the stability of field instruments net-working it can be seen from Figure 14 that the FOI-LEACHprotocol significantly extends the death time of the first
1800
2000
1000
1600
210060
0
200
8000
120040
0
1400
Number of rounds
0
002
004
006
008
01
012
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 10 Comparison of average residual energy in each round without power supply
Table 3 Statistics of the average residual energy (J) of nodes of thefour protocols without power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0075 0007 0 0SEP 0094 002 0 0PECRP 0088 0053 0 0FOI-LEACH 0113 0092 0043 152times10minus5
12 Journal of Electrical and Computer Engineering
ABC
0
1
2
3
4
5
6
7Co
mpa
rison
of C
Hs i
n ea
ch re
gion
2 3 4 5 6 7 8 9 101Number of rounds
(a)
0
2
4
6
8
10
12
14
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(d)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 11 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol without power supply
Journal of Electrical and Computer Engineering 13
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
2000
4000
6000
8000
10000
12000
Pack
ets t
o BS
LEACHSEP
PECRPImproved protocol
Figure 12 Comparison of packets sent to BS from CHs without power supply
times104
200
400
600
800
1000
1200
2000
1800
21000
1400
1600
Number of rounds
0
2
4
6
8
10
12
Pack
ets t
o CH
LEACHSEP
PECRPImproved protocol
Figure 13 Comparison of packets sent to CHs from member nodes without power supply
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
LEACHSEP
PECRPImproved protocol
Figure 14 Comparison of live nodes in each round with power supply
14 Journal of Electrical and Computer Engineering
Table 4 Statistics number of rounds of dead nodes of the four protocols with power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 177 204 232 341SEP 185 210 264 665PECRP 392 430 493 530FOI-LEACH 555 716 1238 2246
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
002
004
006
008
01
012
014
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 15 Comparison of average residual energy in each round with power supply
Table 5 Statistics of the average residual energy (J) of nodes of the four protocols with power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0086 0018 0 0SEP 0105 0036 0001 0PECRP 0099 007 0 0FOI-LEACH 0124 0109 0062 0001
0
1
2
3
4
5
6
7
8
Com
paris
on o
f CH
s in
each
regi
on
2 3 4 5 6 7 8 9 101Number of rounds
ABC
(a)
0
2
4
6
8
10
12
1415
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
Figure 16 Continued
Journal of Electrical and Computer Engineering 15
0
2
4
6
8
10
12
14
16N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14
16
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(d)
0
2
4
6
8
10
12
14
16
18
20
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 16 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol with power supply
0
2000
4000
6000
8000
10000
12000
14000
Pack
ets t
o BS
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 17 Comparison of packets sent to BS from CHs with power supply
16 Journal of Electrical and Computer Engineering
node e supplied energy promotes the extension of thenetwork lifetime and the stability of the networking for thefour protocols in varying degrees For the LEACH protocolthe node began to die at round 177 SEP protocol at round185 PECRP protocol at round 392 and round 555 for theimproved FOI-LEACH protocol
e distributions of the number of clusters in the fourprotocols with energy supply simulated for 10 rounds ofrandom elections are shown in Figure 16 Like the previousfigures Figure 16(a) represents the statistics number of CHsof each zone of FOI-LEACH protocol Figures 16(b)ndash16(e)represent the statistics number of CHs of FOI-LEACHprotocol LEACH protocol SEP protocol and PECRPprotocol respectively Due to the efficient schemes of CHselecting and clustering the FOI-LEACH protocol showssignificantly better performance than the other threeprotocols
(4) Network (roughput In the environment of self-energyas shown in Figure 17 the total number of packets sent toBS of the LEACH protocol SEP protocol PECRP protocoland the proposed FOI-LEACH protocol is approximately2428 3080 3746 and 13265 respectively Moreover inFigure 18 the total number of packages sent to CHs of theLEACH protocol SEP protocol PECRP protocol andFOI-LEACH protocol is approximately 21400 2430044000 and 123200 respectively We can find that the totalnumber of packets sent by our protocol to BS and CHs ismuch higher than the other protocols which also dem-onstrated that the proposed protocol has a better networkthroughout
6 Conclusions
According to the characteristics of field observation in-strument networking an improved protocol FOI-LEACHbased on LEACH protocol was proposed in this paper Byconsidering the energy factor in the CH election threshold
and referring to the SEP protocol to set up two kinds ofnodes with different initial energies which are calledadvanced nodes and normal nodes the network model offield observation instruments has been established Inaddition to solve the problem that the LEACH protocolconsumes much energy during transmission and results inuneven energy consumption for the direct and long-distance transmission the improved protocol adopted the3 zones of partitioning mechanism and the multihoptransmission mechanism to alleviate and avoid the ldquohotspotrdquo problems Furthermore energy supplies were addedto the nodes in A and B zones that are responsible formore energy transmission so as to balance the energyconsumption of the network and prolong the networklifetime In the simulation experiments we compared theperformance of the FOI-LEACH protocol with theLEACH SEP and PECRP protocols in two cases with orwithout energy supply Comparing performance indica-tors of network lifetime energy consumption rate sta-bility and network throughput the proposed FOI-LEACH protocol can slow down the death of nodes andthe energy consumption rate obviously and shows asignificantly better performance than other three proto-cols e experimental results demonstrated that the FOI-LEACH protocol could balance network energy con-sumption and alleviate the ldquohot spotrdquo problem to extendthe lifetime of network nodes in the field observationinstruments network e future work is to implementand port the improved protocol to the hardware of net-working node we designed and developed previously andtest and verify the feasibility and stability of the protocolin the actual situation
Data Availability
e initial nodes are generated randomly in the networkand there are no observation data used in the simulationexperiments
0
20000
40000
60000
80000
100000
120000
140000
Pack
ets t
o CH
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 18 Comparison of packets sent to CHs from nodes with power supply
Journal of Electrical and Computer Engineering 17
Conflicts of Interest
e authors declare that there are no conflicts of interest
Acknowledgments
is work was supported by the National Nature ScienceFoundation of China (Grant no 61862038) the LanzhouTalent Innovation and Entrepreneurship Technology PlanProject (no 2019-RC-14) and the Foundation of a HundredYouth Talents Training Program of Lanzhou JiaotongUniversity
References
[1] J Y Huo Z N Ren and Y R Yang A Kind of InstrumentNetwork Node Equipment and Monitoring System ChinesePatents Beijing China 2017
[2] J Y Huo Key Technology and Application Research ofE-Science Virtual Joint Observation System for Geoscience inCold and Dry Regions University of Chinese Academy ofSciences Beijing China 2012
[3] I F Akyildiz W L Weilian Su Y Sankarasubramaniam andE Cayirci ldquoA survey on sensor networksrdquo IEEE Communi-cations Magazine vol 40 no 8 pp 102ndash114 2002
[4] W R Heinzelman A Chandrakasan and H BalakrishnanldquoEnergy-efficient communication protocol for wirelessmicrosensor networksrdquo in Proceedings of the 33rd HawaiiIntentional Conference on System Sciences Maui HI USAJanuary 2000
[5] D Mehta and S Saxena ldquoA comparative analysis of energyefficient hierarchical routing protocols for wireless sensornetworksrdquo in Proceedings of the 2018 4th InternationalConference on Computing Sciences (ICCS) pp 53ndash58Jalandhar India August 2018
[6] C Karlof and D Wagner ldquoSecure routing in wireless sensornetworks attacks and countermeasuresrdquo Ad Hoc Networksvol 1 2003
[7] L B Oliveira A Ferreira M A Vilaca et al ldquoSecLEACH-onthe security of clustered sensor networksrdquo Signal Processingvol 87 2007
[8] Y Y Gu GW Bai and J J Tao ldquoAZM-LEACH autonomouszone-based multi-hop routing protocol in WSNsrdquo ComputerEngineering and Applications vol 47 no 20 pp 58ndash61 2011
[9] L XWang Research on Routing Technology ofWireless SensorNetworks Based on Data Aggregation Shenyang LigongUniversity Shenyang China 2015
[10] J P Shao Research on Key Energy-Efficient Routing Tech-nology of WSN Based on Cluster Shenyang Ligong UniversityShenyang China 2015
[11] V K Arora V Sharma and M Sachdeva ldquoA survey onLEACH and otherrsquos routing protocols in wireless sensornetworkrdquo Optik vol 127 no 16 pp 6590ndash6600 2016
[12] W B Heinzelman A P Chandrakasan and H BalakrishnanldquoAn application-specific protocol architecture for wirelessmicrosensor networksrdquo IEEE Transactions on WirelessCommunications vol 1 no 4 pp 660ndash670 2002
[13] S Al-Sodairi and R Ouni ldquoReliable and energy-efficientmulti-hop LEACH-based clustering protocol for wirelesssensor networksrdquo Sustainable Computing Informatics andSystems vol 20 pp 1ndash13 2018
[14] O Younis and S Fahmy ldquoHEED a hybrid energy-efficientdistributed clustering approach for ad hoc sensor networksrdquo
IEEE Transactions on Mobile Computing vol 3 no 4pp 366ndash379 2004
[15] B B Chen and Y L Shi ldquoWSN routing protocol based oncluster heads selection in regionsrdquo Computer Engineeringvol 37 no 19 pp 96ndash98 2011
[16] P Azada ldquoCluster head selection in wireless sensor networksunder fuzzy environmentrdquo ISRN Sensor Networks vol 2013Article ID 909086 8 pages 2013
[17] S Soro and W B Heinzelman ldquoCluster head election tech-niques for coverage preservation in wireless sensor networksrdquoAd Hoc Networks vol 7 no 5 pp 955ndash972 2009
[18] A akkar ldquoDEAL distance and energy based advancedleach protocolrdquo in Proceedings of the International Conferenceon Information and Communication Technology for IntelligentSystems pp 370ndash376 Ahmedabad India March 2017
[19] T Y Chang W N Liu Y Zhang and H Y Li ldquoOptimizedLEACH protocol based on distance and energy of clusterheadrdquo Journal of Hebei University (Natural Science Edition)vol 39 no 2 pp 194ndash200 2019
[20] P Mehra M Doja and B Alam ldquoStability enhancement inLEACH (SE-LEACH) for homogeneousWSNrdquo EAI EndorsedTransactions on Scalable Information Systems vol 6 no 20pp 1ndash9 2019
[21] G Smaragdakis I Matta and A Bestavros ldquoSEP a stableelection protocol for clustered heterogeneous wireless sensornetworksrdquo in Proceedings of the Second InternationalWorkshop on Sensor and Actor Network Protocols and Ap-plications (SANPA 2004) pp 1ndash11 Boston MA USA June2004
[22] F S Hu and Q Xiao ldquoMulti-hop routing algorithm of energy-balancing based on LEACHrdquo Journal of Chinese ComputerSystems vol 35 no 1 pp 72ndash75 2014
[23] C F Li M Ye G H Chen and J Wu ldquoAn energy-efficientunequal clustering mechanism for wireless sensor networksrdquoin Proceedings of the IEEE International Conference on MobileAdhoc and Sensor Systems Conference p 604 WashingtonDC USA November 2005
[24] E Alnawafa I Marghescu and MHT ldquoMulti-hop techniquefor the improvement of leach protocolrdquo in Proceedings of the2016 15th RoEduNet Conference Networking in Education andResearch pp 1ndash5 Bucharest Romania September 2016
[25] E Alnawafa and I Marghescu ldquoIMHT improved MHT-LEACH protocol for wireless sensor networksrdquo in Proceedingsof the 2017 8th International Conference on Information andCommunication Systems (ICICS) pp 246ndash251 Irbid JordanApril 2017
[26] J Y Huo Z Zhang and C Tao ldquoUsing IPv6 address ad-vantage to build Network Node of Field observation In-struments in cold and arid areasrdquo China Education Networkno 5 pp 45-46 2018
[27] L Mateu and F Moll ldquoReview of energy harvesting tech-niques and applications for microelectronicsrdquo in Proceedingsof the International Society for Optical Engineering pp 359ndash373 Bellingham WA USA October 2005
[28] G Wang and R Y Wang ldquoRouting algorithm based oncluster-head optimization for self-energized wireless sensornetworkrdquo Journal of Computer Applications vol 38 no 334pp 201ndash216 2018
[29] X P Fan X Yang S Q Liu and Z H Qu ldquoClusteringrouting algorithm for wireless sensor networks with powerharvestingrdquo Computer Engineering vol 39 no 11 pp 126ndash134 2008
18 Journal of Electrical and Computer Engineering
[30] C H Zhang ldquoStudy on the energy heterogeneous clusteringrouting protocol for wireless sensor networksrdquo Science ampTechnology Vision no 13 pp 71+164ndash165 2012
[31] T Liu and F Li ldquoPower-efficient clustering routing protocolbased on applications in wireless sensor networkrdquo in Pro-ceedings of the International Conference on Wireless Com-munications IEEE Press Melbourne Australia September2009
Journal of Electrical and Computer Engineering 19
AB
(a)
AB
(b)
ABC
(c)
ABC
(d)
ABC
(e)
Figure 5 Partitioning scheme (a) Partitioning scheme 1 SaltSb (b) Partitioning scheme 2 SaSb (c) Partitioning scheme 1 SaSbltSc (d)Partitioning scheme 1 SaltSbltSc (e) Partitioning scheme 1 SaScltSb
AeqBAsBAeqBsC
AsBsCAeqCsB
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
Figure 6 Comparison of active nodes in each round
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
002
004
006
008
01
012
Ave
rage
resid
ual e
nerg
y
AeqBAsBAeqBsC
AsBsCAeqCsB
Figure 7 Comparison of average residual energy in each round
10 Journal of Electrical and Computer Engineering
(2) Average Residual Energy and Energy Dissipation RateFigure 10 shows the graph of the average residual energy ofthe network running 2100 rounds without being self-en-ergized Combined with the network average residual en-ergy which is shown in Table 3 it can be drawn that the FOI-LEACH protocol is more slowly energy consumed Besidesit can be seen from Figure 10 that the energy consumption
rate of the improved network is significantly reduced toachieve the purpose of delaying energy consumption andextending network life
(3) Stability e stability of networking was evaluated fromtwo aspects First it can be seen from Figure 9 that the FOI-LEACH protocol significantly extends the death time of the
Self-energized
400
420
440
460
480
500
520
540
Dea
th ti
me o
f the
firs
t nod
e
01 02 03 04 05 06 07 08 09 10α
Figure 8 Impact of parameters α and β on the network lifetime
LEACHSEP
PECRPImproved protocol
400
160060
0
2000
1000
1200
140020
0
1800
21000
800
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
Figure 9 Comparison of live nodes in each round without power supply
Table 2 Statistics number of rounds of dead nodes of the four protocols without power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 135 160 204 276SEP 174 191 226 462PECRP 338 374 412 438FOI-LEACH 481 684 1272 2042
Journal of Electrical and Computer Engineering 11
first node For the LEACH protocol the nodes began to dieat round 135 SEP protocol at round 174 and PECRPprotocol at round 338 Because the energy factor is takeninto account in selecting the CH energy and distance factorsare taken into account in clustering and the adopted zone-based autonomous multihop communication model mini-mizes the Hello control package the nodes die at round 481for the FOI-LEACH protocol As a result the FOI-LEACHprotocol has better performance than other protocols
Figure 11 shows the distribution of the number ofclusters of the four protocols without energy supply simulatedfor 10 rounds of random elections in which Figure 11(a)represents the statistics number of CHs in each zone of theFOI-LEACH protocol and Figure 11(b) represents the sta-tistics number of CHs in the whole network of FOI-LEACHprotocol Figures 11(c)ndash11(e) represent the statistics numberof CHs of LEACH SEP and PECRP protocols respectively Itcan be seen that the number of CHs of FOI-LEACH protocolis more stable than that of LEACH SEP and PECRP BecauseLEACH and SEP randomly select CHs the number of CHsproduced was unstable e FOI-LEACH protocol formsclusters by selecting CHs with a competitive radius and thenumber of CHs is relatively stable
(4) Network (roughput Figure 12 shows that in theLEACH protocol SEP protocol PECRP protocol and ourproposed FOI-LEACH protocol the total number of packets
sent to BS is approximately 900 2580 2980 and 11140respectively Moreover Figure 13 shows that in the LEACHprotocol SEP protocol PECRP protocol and FOI-LEACHprotocol the total number of packages sent to CHs is ap-proximately 7500 21000 38200 and 119000 respectively Itis because the proposed scheme has a high network lifetimethe total number of packets sent to BS and CHs is muchhigher than other protocols
542 Experiments with Energy Supply
(1) Network Lifetime Figure 14 shows the number of sur-viving nodes in the network when the network runs for 2300rounds self-energized According to the statistics of deathnodes in Table 4 we can find that the network lifetime of thefour protocols all has been extended e network failure ofthe LEACH protocol occurred at round 341 the network ofthe SEP protocol expires at round 665 and network failure ofPECRP protocol at round 530 and the FOI-LEACH pro-tocol was not expired until round 2246 which significantlyincreased the network survival time It is demonstrated thatthe improved schemes can work well in both the environ-ments with or without power supply
(2) Average Residual Energy and Energy Dissipation RateFigure 15 shows the graph of the average residual energy ofthe network running 2300 rounds self-energized Combinedwith the network average residual energy which shown inTable 5 it can be drawn that the FOI-LEACH protocol ismore slowly energy consumed Besides it can be seen fromFigure 15 that the energy consumption rate of the improvednetwork is significantly reduced to achieve the purpose ofdelaying energy consumption and extending network life
(3) Stability For the stability of field instruments net-working it can be seen from Figure 14 that the FOI-LEACHprotocol significantly extends the death time of the first
1800
2000
1000
1600
210060
0
200
8000
120040
0
1400
Number of rounds
0
002
004
006
008
01
012
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 10 Comparison of average residual energy in each round without power supply
Table 3 Statistics of the average residual energy (J) of nodes of thefour protocols without power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0075 0007 0 0SEP 0094 002 0 0PECRP 0088 0053 0 0FOI-LEACH 0113 0092 0043 152times10minus5
12 Journal of Electrical and Computer Engineering
ABC
0
1
2
3
4
5
6
7Co
mpa
rison
of C
Hs i
n ea
ch re
gion
2 3 4 5 6 7 8 9 101Number of rounds
(a)
0
2
4
6
8
10
12
14
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(d)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 11 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol without power supply
Journal of Electrical and Computer Engineering 13
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
2000
4000
6000
8000
10000
12000
Pack
ets t
o BS
LEACHSEP
PECRPImproved protocol
Figure 12 Comparison of packets sent to BS from CHs without power supply
times104
200
400
600
800
1000
1200
2000
1800
21000
1400
1600
Number of rounds
0
2
4
6
8
10
12
Pack
ets t
o CH
LEACHSEP
PECRPImproved protocol
Figure 13 Comparison of packets sent to CHs from member nodes without power supply
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
LEACHSEP
PECRPImproved protocol
Figure 14 Comparison of live nodes in each round with power supply
14 Journal of Electrical and Computer Engineering
Table 4 Statistics number of rounds of dead nodes of the four protocols with power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 177 204 232 341SEP 185 210 264 665PECRP 392 430 493 530FOI-LEACH 555 716 1238 2246
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
002
004
006
008
01
012
014
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 15 Comparison of average residual energy in each round with power supply
Table 5 Statistics of the average residual energy (J) of nodes of the four protocols with power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0086 0018 0 0SEP 0105 0036 0001 0PECRP 0099 007 0 0FOI-LEACH 0124 0109 0062 0001
0
1
2
3
4
5
6
7
8
Com
paris
on o
f CH
s in
each
regi
on
2 3 4 5 6 7 8 9 101Number of rounds
ABC
(a)
0
2
4
6
8
10
12
1415
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
Figure 16 Continued
Journal of Electrical and Computer Engineering 15
0
2
4
6
8
10
12
14
16N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14
16
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(d)
0
2
4
6
8
10
12
14
16
18
20
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 16 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol with power supply
0
2000
4000
6000
8000
10000
12000
14000
Pack
ets t
o BS
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 17 Comparison of packets sent to BS from CHs with power supply
16 Journal of Electrical and Computer Engineering
node e supplied energy promotes the extension of thenetwork lifetime and the stability of the networking for thefour protocols in varying degrees For the LEACH protocolthe node began to die at round 177 SEP protocol at round185 PECRP protocol at round 392 and round 555 for theimproved FOI-LEACH protocol
e distributions of the number of clusters in the fourprotocols with energy supply simulated for 10 rounds ofrandom elections are shown in Figure 16 Like the previousfigures Figure 16(a) represents the statistics number of CHsof each zone of FOI-LEACH protocol Figures 16(b)ndash16(e)represent the statistics number of CHs of FOI-LEACHprotocol LEACH protocol SEP protocol and PECRPprotocol respectively Due to the efficient schemes of CHselecting and clustering the FOI-LEACH protocol showssignificantly better performance than the other threeprotocols
(4) Network (roughput In the environment of self-energyas shown in Figure 17 the total number of packets sent toBS of the LEACH protocol SEP protocol PECRP protocoland the proposed FOI-LEACH protocol is approximately2428 3080 3746 and 13265 respectively Moreover inFigure 18 the total number of packages sent to CHs of theLEACH protocol SEP protocol PECRP protocol andFOI-LEACH protocol is approximately 21400 2430044000 and 123200 respectively We can find that the totalnumber of packets sent by our protocol to BS and CHs ismuch higher than the other protocols which also dem-onstrated that the proposed protocol has a better networkthroughout
6 Conclusions
According to the characteristics of field observation in-strument networking an improved protocol FOI-LEACHbased on LEACH protocol was proposed in this paper Byconsidering the energy factor in the CH election threshold
and referring to the SEP protocol to set up two kinds ofnodes with different initial energies which are calledadvanced nodes and normal nodes the network model offield observation instruments has been established Inaddition to solve the problem that the LEACH protocolconsumes much energy during transmission and results inuneven energy consumption for the direct and long-distance transmission the improved protocol adopted the3 zones of partitioning mechanism and the multihoptransmission mechanism to alleviate and avoid the ldquohotspotrdquo problems Furthermore energy supplies were addedto the nodes in A and B zones that are responsible formore energy transmission so as to balance the energyconsumption of the network and prolong the networklifetime In the simulation experiments we compared theperformance of the FOI-LEACH protocol with theLEACH SEP and PECRP protocols in two cases with orwithout energy supply Comparing performance indica-tors of network lifetime energy consumption rate sta-bility and network throughput the proposed FOI-LEACH protocol can slow down the death of nodes andthe energy consumption rate obviously and shows asignificantly better performance than other three proto-cols e experimental results demonstrated that the FOI-LEACH protocol could balance network energy con-sumption and alleviate the ldquohot spotrdquo problem to extendthe lifetime of network nodes in the field observationinstruments network e future work is to implementand port the improved protocol to the hardware of net-working node we designed and developed previously andtest and verify the feasibility and stability of the protocolin the actual situation
Data Availability
e initial nodes are generated randomly in the networkand there are no observation data used in the simulationexperiments
0
20000
40000
60000
80000
100000
120000
140000
Pack
ets t
o CH
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 18 Comparison of packets sent to CHs from nodes with power supply
Journal of Electrical and Computer Engineering 17
Conflicts of Interest
e authors declare that there are no conflicts of interest
Acknowledgments
is work was supported by the National Nature ScienceFoundation of China (Grant no 61862038) the LanzhouTalent Innovation and Entrepreneurship Technology PlanProject (no 2019-RC-14) and the Foundation of a HundredYouth Talents Training Program of Lanzhou JiaotongUniversity
References
[1] J Y Huo Z N Ren and Y R Yang A Kind of InstrumentNetwork Node Equipment and Monitoring System ChinesePatents Beijing China 2017
[2] J Y Huo Key Technology and Application Research ofE-Science Virtual Joint Observation System for Geoscience inCold and Dry Regions University of Chinese Academy ofSciences Beijing China 2012
[3] I F Akyildiz W L Weilian Su Y Sankarasubramaniam andE Cayirci ldquoA survey on sensor networksrdquo IEEE Communi-cations Magazine vol 40 no 8 pp 102ndash114 2002
[4] W R Heinzelman A Chandrakasan and H BalakrishnanldquoEnergy-efficient communication protocol for wirelessmicrosensor networksrdquo in Proceedings of the 33rd HawaiiIntentional Conference on System Sciences Maui HI USAJanuary 2000
[5] D Mehta and S Saxena ldquoA comparative analysis of energyefficient hierarchical routing protocols for wireless sensornetworksrdquo in Proceedings of the 2018 4th InternationalConference on Computing Sciences (ICCS) pp 53ndash58Jalandhar India August 2018
[6] C Karlof and D Wagner ldquoSecure routing in wireless sensornetworks attacks and countermeasuresrdquo Ad Hoc Networksvol 1 2003
[7] L B Oliveira A Ferreira M A Vilaca et al ldquoSecLEACH-onthe security of clustered sensor networksrdquo Signal Processingvol 87 2007
[8] Y Y Gu GW Bai and J J Tao ldquoAZM-LEACH autonomouszone-based multi-hop routing protocol in WSNsrdquo ComputerEngineering and Applications vol 47 no 20 pp 58ndash61 2011
[9] L XWang Research on Routing Technology ofWireless SensorNetworks Based on Data Aggregation Shenyang LigongUniversity Shenyang China 2015
[10] J P Shao Research on Key Energy-Efficient Routing Tech-nology of WSN Based on Cluster Shenyang Ligong UniversityShenyang China 2015
[11] V K Arora V Sharma and M Sachdeva ldquoA survey onLEACH and otherrsquos routing protocols in wireless sensornetworkrdquo Optik vol 127 no 16 pp 6590ndash6600 2016
[12] W B Heinzelman A P Chandrakasan and H BalakrishnanldquoAn application-specific protocol architecture for wirelessmicrosensor networksrdquo IEEE Transactions on WirelessCommunications vol 1 no 4 pp 660ndash670 2002
[13] S Al-Sodairi and R Ouni ldquoReliable and energy-efficientmulti-hop LEACH-based clustering protocol for wirelesssensor networksrdquo Sustainable Computing Informatics andSystems vol 20 pp 1ndash13 2018
[14] O Younis and S Fahmy ldquoHEED a hybrid energy-efficientdistributed clustering approach for ad hoc sensor networksrdquo
IEEE Transactions on Mobile Computing vol 3 no 4pp 366ndash379 2004
[15] B B Chen and Y L Shi ldquoWSN routing protocol based oncluster heads selection in regionsrdquo Computer Engineeringvol 37 no 19 pp 96ndash98 2011
[16] P Azada ldquoCluster head selection in wireless sensor networksunder fuzzy environmentrdquo ISRN Sensor Networks vol 2013Article ID 909086 8 pages 2013
[17] S Soro and W B Heinzelman ldquoCluster head election tech-niques for coverage preservation in wireless sensor networksrdquoAd Hoc Networks vol 7 no 5 pp 955ndash972 2009
[18] A akkar ldquoDEAL distance and energy based advancedleach protocolrdquo in Proceedings of the International Conferenceon Information and Communication Technology for IntelligentSystems pp 370ndash376 Ahmedabad India March 2017
[19] T Y Chang W N Liu Y Zhang and H Y Li ldquoOptimizedLEACH protocol based on distance and energy of clusterheadrdquo Journal of Hebei University (Natural Science Edition)vol 39 no 2 pp 194ndash200 2019
[20] P Mehra M Doja and B Alam ldquoStability enhancement inLEACH (SE-LEACH) for homogeneousWSNrdquo EAI EndorsedTransactions on Scalable Information Systems vol 6 no 20pp 1ndash9 2019
[21] G Smaragdakis I Matta and A Bestavros ldquoSEP a stableelection protocol for clustered heterogeneous wireless sensornetworksrdquo in Proceedings of the Second InternationalWorkshop on Sensor and Actor Network Protocols and Ap-plications (SANPA 2004) pp 1ndash11 Boston MA USA June2004
[22] F S Hu and Q Xiao ldquoMulti-hop routing algorithm of energy-balancing based on LEACHrdquo Journal of Chinese ComputerSystems vol 35 no 1 pp 72ndash75 2014
[23] C F Li M Ye G H Chen and J Wu ldquoAn energy-efficientunequal clustering mechanism for wireless sensor networksrdquoin Proceedings of the IEEE International Conference on MobileAdhoc and Sensor Systems Conference p 604 WashingtonDC USA November 2005
[24] E Alnawafa I Marghescu and MHT ldquoMulti-hop techniquefor the improvement of leach protocolrdquo in Proceedings of the2016 15th RoEduNet Conference Networking in Education andResearch pp 1ndash5 Bucharest Romania September 2016
[25] E Alnawafa and I Marghescu ldquoIMHT improved MHT-LEACH protocol for wireless sensor networksrdquo in Proceedingsof the 2017 8th International Conference on Information andCommunication Systems (ICICS) pp 246ndash251 Irbid JordanApril 2017
[26] J Y Huo Z Zhang and C Tao ldquoUsing IPv6 address ad-vantage to build Network Node of Field observation In-struments in cold and arid areasrdquo China Education Networkno 5 pp 45-46 2018
[27] L Mateu and F Moll ldquoReview of energy harvesting tech-niques and applications for microelectronicsrdquo in Proceedingsof the International Society for Optical Engineering pp 359ndash373 Bellingham WA USA October 2005
[28] G Wang and R Y Wang ldquoRouting algorithm based oncluster-head optimization for self-energized wireless sensornetworkrdquo Journal of Computer Applications vol 38 no 334pp 201ndash216 2018
[29] X P Fan X Yang S Q Liu and Z H Qu ldquoClusteringrouting algorithm for wireless sensor networks with powerharvestingrdquo Computer Engineering vol 39 no 11 pp 126ndash134 2008
18 Journal of Electrical and Computer Engineering
[30] C H Zhang ldquoStudy on the energy heterogeneous clusteringrouting protocol for wireless sensor networksrdquo Science ampTechnology Vision no 13 pp 71+164ndash165 2012
[31] T Liu and F Li ldquoPower-efficient clustering routing protocolbased on applications in wireless sensor networkrdquo in Pro-ceedings of the International Conference on Wireless Com-munications IEEE Press Melbourne Australia September2009
Journal of Electrical and Computer Engineering 19
(2) Average Residual Energy and Energy Dissipation RateFigure 10 shows the graph of the average residual energy ofthe network running 2100 rounds without being self-en-ergized Combined with the network average residual en-ergy which is shown in Table 3 it can be drawn that the FOI-LEACH protocol is more slowly energy consumed Besidesit can be seen from Figure 10 that the energy consumption
rate of the improved network is significantly reduced toachieve the purpose of delaying energy consumption andextending network life
(3) Stability e stability of networking was evaluated fromtwo aspects First it can be seen from Figure 9 that the FOI-LEACH protocol significantly extends the death time of the
Self-energized
400
420
440
460
480
500
520
540
Dea
th ti
me o
f the
firs
t nod
e
01 02 03 04 05 06 07 08 09 10α
Figure 8 Impact of parameters α and β on the network lifetime
LEACHSEP
PECRPImproved protocol
400
160060
0
2000
1000
1200
140020
0
1800
21000
800
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
Figure 9 Comparison of live nodes in each round without power supply
Table 2 Statistics number of rounds of dead nodes of the four protocols without power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 135 160 204 276SEP 174 191 226 462PECRP 338 374 412 438FOI-LEACH 481 684 1272 2042
Journal of Electrical and Computer Engineering 11
first node For the LEACH protocol the nodes began to dieat round 135 SEP protocol at round 174 and PECRPprotocol at round 338 Because the energy factor is takeninto account in selecting the CH energy and distance factorsare taken into account in clustering and the adopted zone-based autonomous multihop communication model mini-mizes the Hello control package the nodes die at round 481for the FOI-LEACH protocol As a result the FOI-LEACHprotocol has better performance than other protocols
Figure 11 shows the distribution of the number ofclusters of the four protocols without energy supply simulatedfor 10 rounds of random elections in which Figure 11(a)represents the statistics number of CHs in each zone of theFOI-LEACH protocol and Figure 11(b) represents the sta-tistics number of CHs in the whole network of FOI-LEACHprotocol Figures 11(c)ndash11(e) represent the statistics numberof CHs of LEACH SEP and PECRP protocols respectively Itcan be seen that the number of CHs of FOI-LEACH protocolis more stable than that of LEACH SEP and PECRP BecauseLEACH and SEP randomly select CHs the number of CHsproduced was unstable e FOI-LEACH protocol formsclusters by selecting CHs with a competitive radius and thenumber of CHs is relatively stable
(4) Network (roughput Figure 12 shows that in theLEACH protocol SEP protocol PECRP protocol and ourproposed FOI-LEACH protocol the total number of packets
sent to BS is approximately 900 2580 2980 and 11140respectively Moreover Figure 13 shows that in the LEACHprotocol SEP protocol PECRP protocol and FOI-LEACHprotocol the total number of packages sent to CHs is ap-proximately 7500 21000 38200 and 119000 respectively Itis because the proposed scheme has a high network lifetimethe total number of packets sent to BS and CHs is muchhigher than other protocols
542 Experiments with Energy Supply
(1) Network Lifetime Figure 14 shows the number of sur-viving nodes in the network when the network runs for 2300rounds self-energized According to the statistics of deathnodes in Table 4 we can find that the network lifetime of thefour protocols all has been extended e network failure ofthe LEACH protocol occurred at round 341 the network ofthe SEP protocol expires at round 665 and network failure ofPECRP protocol at round 530 and the FOI-LEACH pro-tocol was not expired until round 2246 which significantlyincreased the network survival time It is demonstrated thatthe improved schemes can work well in both the environ-ments with or without power supply
(2) Average Residual Energy and Energy Dissipation RateFigure 15 shows the graph of the average residual energy ofthe network running 2300 rounds self-energized Combinedwith the network average residual energy which shown inTable 5 it can be drawn that the FOI-LEACH protocol ismore slowly energy consumed Besides it can be seen fromFigure 15 that the energy consumption rate of the improvednetwork is significantly reduced to achieve the purpose ofdelaying energy consumption and extending network life
(3) Stability For the stability of field instruments net-working it can be seen from Figure 14 that the FOI-LEACHprotocol significantly extends the death time of the first
1800
2000
1000
1600
210060
0
200
8000
120040
0
1400
Number of rounds
0
002
004
006
008
01
012
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 10 Comparison of average residual energy in each round without power supply
Table 3 Statistics of the average residual energy (J) of nodes of thefour protocols without power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0075 0007 0 0SEP 0094 002 0 0PECRP 0088 0053 0 0FOI-LEACH 0113 0092 0043 152times10minus5
12 Journal of Electrical and Computer Engineering
ABC
0
1
2
3
4
5
6
7Co
mpa
rison
of C
Hs i
n ea
ch re
gion
2 3 4 5 6 7 8 9 101Number of rounds
(a)
0
2
4
6
8
10
12
14
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(d)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 11 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol without power supply
Journal of Electrical and Computer Engineering 13
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
2000
4000
6000
8000
10000
12000
Pack
ets t
o BS
LEACHSEP
PECRPImproved protocol
Figure 12 Comparison of packets sent to BS from CHs without power supply
times104
200
400
600
800
1000
1200
2000
1800
21000
1400
1600
Number of rounds
0
2
4
6
8
10
12
Pack
ets t
o CH
LEACHSEP
PECRPImproved protocol
Figure 13 Comparison of packets sent to CHs from member nodes without power supply
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
LEACHSEP
PECRPImproved protocol
Figure 14 Comparison of live nodes in each round with power supply
14 Journal of Electrical and Computer Engineering
Table 4 Statistics number of rounds of dead nodes of the four protocols with power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 177 204 232 341SEP 185 210 264 665PECRP 392 430 493 530FOI-LEACH 555 716 1238 2246
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
002
004
006
008
01
012
014
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 15 Comparison of average residual energy in each round with power supply
Table 5 Statistics of the average residual energy (J) of nodes of the four protocols with power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0086 0018 0 0SEP 0105 0036 0001 0PECRP 0099 007 0 0FOI-LEACH 0124 0109 0062 0001
0
1
2
3
4
5
6
7
8
Com
paris
on o
f CH
s in
each
regi
on
2 3 4 5 6 7 8 9 101Number of rounds
ABC
(a)
0
2
4
6
8
10
12
1415
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
Figure 16 Continued
Journal of Electrical and Computer Engineering 15
0
2
4
6
8
10
12
14
16N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14
16
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(d)
0
2
4
6
8
10
12
14
16
18
20
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 16 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol with power supply
0
2000
4000
6000
8000
10000
12000
14000
Pack
ets t
o BS
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 17 Comparison of packets sent to BS from CHs with power supply
16 Journal of Electrical and Computer Engineering
node e supplied energy promotes the extension of thenetwork lifetime and the stability of the networking for thefour protocols in varying degrees For the LEACH protocolthe node began to die at round 177 SEP protocol at round185 PECRP protocol at round 392 and round 555 for theimproved FOI-LEACH protocol
e distributions of the number of clusters in the fourprotocols with energy supply simulated for 10 rounds ofrandom elections are shown in Figure 16 Like the previousfigures Figure 16(a) represents the statistics number of CHsof each zone of FOI-LEACH protocol Figures 16(b)ndash16(e)represent the statistics number of CHs of FOI-LEACHprotocol LEACH protocol SEP protocol and PECRPprotocol respectively Due to the efficient schemes of CHselecting and clustering the FOI-LEACH protocol showssignificantly better performance than the other threeprotocols
(4) Network (roughput In the environment of self-energyas shown in Figure 17 the total number of packets sent toBS of the LEACH protocol SEP protocol PECRP protocoland the proposed FOI-LEACH protocol is approximately2428 3080 3746 and 13265 respectively Moreover inFigure 18 the total number of packages sent to CHs of theLEACH protocol SEP protocol PECRP protocol andFOI-LEACH protocol is approximately 21400 2430044000 and 123200 respectively We can find that the totalnumber of packets sent by our protocol to BS and CHs ismuch higher than the other protocols which also dem-onstrated that the proposed protocol has a better networkthroughout
6 Conclusions
According to the characteristics of field observation in-strument networking an improved protocol FOI-LEACHbased on LEACH protocol was proposed in this paper Byconsidering the energy factor in the CH election threshold
and referring to the SEP protocol to set up two kinds ofnodes with different initial energies which are calledadvanced nodes and normal nodes the network model offield observation instruments has been established Inaddition to solve the problem that the LEACH protocolconsumes much energy during transmission and results inuneven energy consumption for the direct and long-distance transmission the improved protocol adopted the3 zones of partitioning mechanism and the multihoptransmission mechanism to alleviate and avoid the ldquohotspotrdquo problems Furthermore energy supplies were addedto the nodes in A and B zones that are responsible formore energy transmission so as to balance the energyconsumption of the network and prolong the networklifetime In the simulation experiments we compared theperformance of the FOI-LEACH protocol with theLEACH SEP and PECRP protocols in two cases with orwithout energy supply Comparing performance indica-tors of network lifetime energy consumption rate sta-bility and network throughput the proposed FOI-LEACH protocol can slow down the death of nodes andthe energy consumption rate obviously and shows asignificantly better performance than other three proto-cols e experimental results demonstrated that the FOI-LEACH protocol could balance network energy con-sumption and alleviate the ldquohot spotrdquo problem to extendthe lifetime of network nodes in the field observationinstruments network e future work is to implementand port the improved protocol to the hardware of net-working node we designed and developed previously andtest and verify the feasibility and stability of the protocolin the actual situation
Data Availability
e initial nodes are generated randomly in the networkand there are no observation data used in the simulationexperiments
0
20000
40000
60000
80000
100000
120000
140000
Pack
ets t
o CH
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 18 Comparison of packets sent to CHs from nodes with power supply
Journal of Electrical and Computer Engineering 17
Conflicts of Interest
e authors declare that there are no conflicts of interest
Acknowledgments
is work was supported by the National Nature ScienceFoundation of China (Grant no 61862038) the LanzhouTalent Innovation and Entrepreneurship Technology PlanProject (no 2019-RC-14) and the Foundation of a HundredYouth Talents Training Program of Lanzhou JiaotongUniversity
References
[1] J Y Huo Z N Ren and Y R Yang A Kind of InstrumentNetwork Node Equipment and Monitoring System ChinesePatents Beijing China 2017
[2] J Y Huo Key Technology and Application Research ofE-Science Virtual Joint Observation System for Geoscience inCold and Dry Regions University of Chinese Academy ofSciences Beijing China 2012
[3] I F Akyildiz W L Weilian Su Y Sankarasubramaniam andE Cayirci ldquoA survey on sensor networksrdquo IEEE Communi-cations Magazine vol 40 no 8 pp 102ndash114 2002
[4] W R Heinzelman A Chandrakasan and H BalakrishnanldquoEnergy-efficient communication protocol for wirelessmicrosensor networksrdquo in Proceedings of the 33rd HawaiiIntentional Conference on System Sciences Maui HI USAJanuary 2000
[5] D Mehta and S Saxena ldquoA comparative analysis of energyefficient hierarchical routing protocols for wireless sensornetworksrdquo in Proceedings of the 2018 4th InternationalConference on Computing Sciences (ICCS) pp 53ndash58Jalandhar India August 2018
[6] C Karlof and D Wagner ldquoSecure routing in wireless sensornetworks attacks and countermeasuresrdquo Ad Hoc Networksvol 1 2003
[7] L B Oliveira A Ferreira M A Vilaca et al ldquoSecLEACH-onthe security of clustered sensor networksrdquo Signal Processingvol 87 2007
[8] Y Y Gu GW Bai and J J Tao ldquoAZM-LEACH autonomouszone-based multi-hop routing protocol in WSNsrdquo ComputerEngineering and Applications vol 47 no 20 pp 58ndash61 2011
[9] L XWang Research on Routing Technology ofWireless SensorNetworks Based on Data Aggregation Shenyang LigongUniversity Shenyang China 2015
[10] J P Shao Research on Key Energy-Efficient Routing Tech-nology of WSN Based on Cluster Shenyang Ligong UniversityShenyang China 2015
[11] V K Arora V Sharma and M Sachdeva ldquoA survey onLEACH and otherrsquos routing protocols in wireless sensornetworkrdquo Optik vol 127 no 16 pp 6590ndash6600 2016
[12] W B Heinzelman A P Chandrakasan and H BalakrishnanldquoAn application-specific protocol architecture for wirelessmicrosensor networksrdquo IEEE Transactions on WirelessCommunications vol 1 no 4 pp 660ndash670 2002
[13] S Al-Sodairi and R Ouni ldquoReliable and energy-efficientmulti-hop LEACH-based clustering protocol for wirelesssensor networksrdquo Sustainable Computing Informatics andSystems vol 20 pp 1ndash13 2018
[14] O Younis and S Fahmy ldquoHEED a hybrid energy-efficientdistributed clustering approach for ad hoc sensor networksrdquo
IEEE Transactions on Mobile Computing vol 3 no 4pp 366ndash379 2004
[15] B B Chen and Y L Shi ldquoWSN routing protocol based oncluster heads selection in regionsrdquo Computer Engineeringvol 37 no 19 pp 96ndash98 2011
[16] P Azada ldquoCluster head selection in wireless sensor networksunder fuzzy environmentrdquo ISRN Sensor Networks vol 2013Article ID 909086 8 pages 2013
[17] S Soro and W B Heinzelman ldquoCluster head election tech-niques for coverage preservation in wireless sensor networksrdquoAd Hoc Networks vol 7 no 5 pp 955ndash972 2009
[18] A akkar ldquoDEAL distance and energy based advancedleach protocolrdquo in Proceedings of the International Conferenceon Information and Communication Technology for IntelligentSystems pp 370ndash376 Ahmedabad India March 2017
[19] T Y Chang W N Liu Y Zhang and H Y Li ldquoOptimizedLEACH protocol based on distance and energy of clusterheadrdquo Journal of Hebei University (Natural Science Edition)vol 39 no 2 pp 194ndash200 2019
[20] P Mehra M Doja and B Alam ldquoStability enhancement inLEACH (SE-LEACH) for homogeneousWSNrdquo EAI EndorsedTransactions on Scalable Information Systems vol 6 no 20pp 1ndash9 2019
[21] G Smaragdakis I Matta and A Bestavros ldquoSEP a stableelection protocol for clustered heterogeneous wireless sensornetworksrdquo in Proceedings of the Second InternationalWorkshop on Sensor and Actor Network Protocols and Ap-plications (SANPA 2004) pp 1ndash11 Boston MA USA June2004
[22] F S Hu and Q Xiao ldquoMulti-hop routing algorithm of energy-balancing based on LEACHrdquo Journal of Chinese ComputerSystems vol 35 no 1 pp 72ndash75 2014
[23] C F Li M Ye G H Chen and J Wu ldquoAn energy-efficientunequal clustering mechanism for wireless sensor networksrdquoin Proceedings of the IEEE International Conference on MobileAdhoc and Sensor Systems Conference p 604 WashingtonDC USA November 2005
[24] E Alnawafa I Marghescu and MHT ldquoMulti-hop techniquefor the improvement of leach protocolrdquo in Proceedings of the2016 15th RoEduNet Conference Networking in Education andResearch pp 1ndash5 Bucharest Romania September 2016
[25] E Alnawafa and I Marghescu ldquoIMHT improved MHT-LEACH protocol for wireless sensor networksrdquo in Proceedingsof the 2017 8th International Conference on Information andCommunication Systems (ICICS) pp 246ndash251 Irbid JordanApril 2017
[26] J Y Huo Z Zhang and C Tao ldquoUsing IPv6 address ad-vantage to build Network Node of Field observation In-struments in cold and arid areasrdquo China Education Networkno 5 pp 45-46 2018
[27] L Mateu and F Moll ldquoReview of energy harvesting tech-niques and applications for microelectronicsrdquo in Proceedingsof the International Society for Optical Engineering pp 359ndash373 Bellingham WA USA October 2005
[28] G Wang and R Y Wang ldquoRouting algorithm based oncluster-head optimization for self-energized wireless sensornetworkrdquo Journal of Computer Applications vol 38 no 334pp 201ndash216 2018
[29] X P Fan X Yang S Q Liu and Z H Qu ldquoClusteringrouting algorithm for wireless sensor networks with powerharvestingrdquo Computer Engineering vol 39 no 11 pp 126ndash134 2008
18 Journal of Electrical and Computer Engineering
[30] C H Zhang ldquoStudy on the energy heterogeneous clusteringrouting protocol for wireless sensor networksrdquo Science ampTechnology Vision no 13 pp 71+164ndash165 2012
[31] T Liu and F Li ldquoPower-efficient clustering routing protocolbased on applications in wireless sensor networkrdquo in Pro-ceedings of the International Conference on Wireless Com-munications IEEE Press Melbourne Australia September2009
Journal of Electrical and Computer Engineering 19
first node For the LEACH protocol the nodes began to dieat round 135 SEP protocol at round 174 and PECRPprotocol at round 338 Because the energy factor is takeninto account in selecting the CH energy and distance factorsare taken into account in clustering and the adopted zone-based autonomous multihop communication model mini-mizes the Hello control package the nodes die at round 481for the FOI-LEACH protocol As a result the FOI-LEACHprotocol has better performance than other protocols
Figure 11 shows the distribution of the number ofclusters of the four protocols without energy supply simulatedfor 10 rounds of random elections in which Figure 11(a)represents the statistics number of CHs in each zone of theFOI-LEACH protocol and Figure 11(b) represents the sta-tistics number of CHs in the whole network of FOI-LEACHprotocol Figures 11(c)ndash11(e) represent the statistics numberof CHs of LEACH SEP and PECRP protocols respectively Itcan be seen that the number of CHs of FOI-LEACH protocolis more stable than that of LEACH SEP and PECRP BecauseLEACH and SEP randomly select CHs the number of CHsproduced was unstable e FOI-LEACH protocol formsclusters by selecting CHs with a competitive radius and thenumber of CHs is relatively stable
(4) Network (roughput Figure 12 shows that in theLEACH protocol SEP protocol PECRP protocol and ourproposed FOI-LEACH protocol the total number of packets
sent to BS is approximately 900 2580 2980 and 11140respectively Moreover Figure 13 shows that in the LEACHprotocol SEP protocol PECRP protocol and FOI-LEACHprotocol the total number of packages sent to CHs is ap-proximately 7500 21000 38200 and 119000 respectively Itis because the proposed scheme has a high network lifetimethe total number of packets sent to BS and CHs is muchhigher than other protocols
542 Experiments with Energy Supply
(1) Network Lifetime Figure 14 shows the number of sur-viving nodes in the network when the network runs for 2300rounds self-energized According to the statistics of deathnodes in Table 4 we can find that the network lifetime of thefour protocols all has been extended e network failure ofthe LEACH protocol occurred at round 341 the network ofthe SEP protocol expires at round 665 and network failure ofPECRP protocol at round 530 and the FOI-LEACH pro-tocol was not expired until round 2246 which significantlyincreased the network survival time It is demonstrated thatthe improved schemes can work well in both the environ-ments with or without power supply
(2) Average Residual Energy and Energy Dissipation RateFigure 15 shows the graph of the average residual energy ofthe network running 2300 rounds self-energized Combinedwith the network average residual energy which shown inTable 5 it can be drawn that the FOI-LEACH protocol ismore slowly energy consumed Besides it can be seen fromFigure 15 that the energy consumption rate of the improvednetwork is significantly reduced to achieve the purpose ofdelaying energy consumption and extending network life
(3) Stability For the stability of field instruments net-working it can be seen from Figure 14 that the FOI-LEACHprotocol significantly extends the death time of the first
1800
2000
1000
1600
210060
0
200
8000
120040
0
1400
Number of rounds
0
002
004
006
008
01
012
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 10 Comparison of average residual energy in each round without power supply
Table 3 Statistics of the average residual energy (J) of nodes of thefour protocols without power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0075 0007 0 0SEP 0094 002 0 0PECRP 0088 0053 0 0FOI-LEACH 0113 0092 0043 152times10minus5
12 Journal of Electrical and Computer Engineering
ABC
0
1
2
3
4
5
6
7Co
mpa
rison
of C
Hs i
n ea
ch re
gion
2 3 4 5 6 7 8 9 101Number of rounds
(a)
0
2
4
6
8
10
12
14
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(d)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 11 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol without power supply
Journal of Electrical and Computer Engineering 13
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
2000
4000
6000
8000
10000
12000
Pack
ets t
o BS
LEACHSEP
PECRPImproved protocol
Figure 12 Comparison of packets sent to BS from CHs without power supply
times104
200
400
600
800
1000
1200
2000
1800
21000
1400
1600
Number of rounds
0
2
4
6
8
10
12
Pack
ets t
o CH
LEACHSEP
PECRPImproved protocol
Figure 13 Comparison of packets sent to CHs from member nodes without power supply
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
LEACHSEP
PECRPImproved protocol
Figure 14 Comparison of live nodes in each round with power supply
14 Journal of Electrical and Computer Engineering
Table 4 Statistics number of rounds of dead nodes of the four protocols with power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 177 204 232 341SEP 185 210 264 665PECRP 392 430 493 530FOI-LEACH 555 716 1238 2246
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
002
004
006
008
01
012
014
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 15 Comparison of average residual energy in each round with power supply
Table 5 Statistics of the average residual energy (J) of nodes of the four protocols with power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0086 0018 0 0SEP 0105 0036 0001 0PECRP 0099 007 0 0FOI-LEACH 0124 0109 0062 0001
0
1
2
3
4
5
6
7
8
Com
paris
on o
f CH
s in
each
regi
on
2 3 4 5 6 7 8 9 101Number of rounds
ABC
(a)
0
2
4
6
8
10
12
1415
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
Figure 16 Continued
Journal of Electrical and Computer Engineering 15
0
2
4
6
8
10
12
14
16N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14
16
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(d)
0
2
4
6
8
10
12
14
16
18
20
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 16 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol with power supply
0
2000
4000
6000
8000
10000
12000
14000
Pack
ets t
o BS
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 17 Comparison of packets sent to BS from CHs with power supply
16 Journal of Electrical and Computer Engineering
node e supplied energy promotes the extension of thenetwork lifetime and the stability of the networking for thefour protocols in varying degrees For the LEACH protocolthe node began to die at round 177 SEP protocol at round185 PECRP protocol at round 392 and round 555 for theimproved FOI-LEACH protocol
e distributions of the number of clusters in the fourprotocols with energy supply simulated for 10 rounds ofrandom elections are shown in Figure 16 Like the previousfigures Figure 16(a) represents the statistics number of CHsof each zone of FOI-LEACH protocol Figures 16(b)ndash16(e)represent the statistics number of CHs of FOI-LEACHprotocol LEACH protocol SEP protocol and PECRPprotocol respectively Due to the efficient schemes of CHselecting and clustering the FOI-LEACH protocol showssignificantly better performance than the other threeprotocols
(4) Network (roughput In the environment of self-energyas shown in Figure 17 the total number of packets sent toBS of the LEACH protocol SEP protocol PECRP protocoland the proposed FOI-LEACH protocol is approximately2428 3080 3746 and 13265 respectively Moreover inFigure 18 the total number of packages sent to CHs of theLEACH protocol SEP protocol PECRP protocol andFOI-LEACH protocol is approximately 21400 2430044000 and 123200 respectively We can find that the totalnumber of packets sent by our protocol to BS and CHs ismuch higher than the other protocols which also dem-onstrated that the proposed protocol has a better networkthroughout
6 Conclusions
According to the characteristics of field observation in-strument networking an improved protocol FOI-LEACHbased on LEACH protocol was proposed in this paper Byconsidering the energy factor in the CH election threshold
and referring to the SEP protocol to set up two kinds ofnodes with different initial energies which are calledadvanced nodes and normal nodes the network model offield observation instruments has been established Inaddition to solve the problem that the LEACH protocolconsumes much energy during transmission and results inuneven energy consumption for the direct and long-distance transmission the improved protocol adopted the3 zones of partitioning mechanism and the multihoptransmission mechanism to alleviate and avoid the ldquohotspotrdquo problems Furthermore energy supplies were addedto the nodes in A and B zones that are responsible formore energy transmission so as to balance the energyconsumption of the network and prolong the networklifetime In the simulation experiments we compared theperformance of the FOI-LEACH protocol with theLEACH SEP and PECRP protocols in two cases with orwithout energy supply Comparing performance indica-tors of network lifetime energy consumption rate sta-bility and network throughput the proposed FOI-LEACH protocol can slow down the death of nodes andthe energy consumption rate obviously and shows asignificantly better performance than other three proto-cols e experimental results demonstrated that the FOI-LEACH protocol could balance network energy con-sumption and alleviate the ldquohot spotrdquo problem to extendthe lifetime of network nodes in the field observationinstruments network e future work is to implementand port the improved protocol to the hardware of net-working node we designed and developed previously andtest and verify the feasibility and stability of the protocolin the actual situation
Data Availability
e initial nodes are generated randomly in the networkand there are no observation data used in the simulationexperiments
0
20000
40000
60000
80000
100000
120000
140000
Pack
ets t
o CH
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 18 Comparison of packets sent to CHs from nodes with power supply
Journal of Electrical and Computer Engineering 17
Conflicts of Interest
e authors declare that there are no conflicts of interest
Acknowledgments
is work was supported by the National Nature ScienceFoundation of China (Grant no 61862038) the LanzhouTalent Innovation and Entrepreneurship Technology PlanProject (no 2019-RC-14) and the Foundation of a HundredYouth Talents Training Program of Lanzhou JiaotongUniversity
References
[1] J Y Huo Z N Ren and Y R Yang A Kind of InstrumentNetwork Node Equipment and Monitoring System ChinesePatents Beijing China 2017
[2] J Y Huo Key Technology and Application Research ofE-Science Virtual Joint Observation System for Geoscience inCold and Dry Regions University of Chinese Academy ofSciences Beijing China 2012
[3] I F Akyildiz W L Weilian Su Y Sankarasubramaniam andE Cayirci ldquoA survey on sensor networksrdquo IEEE Communi-cations Magazine vol 40 no 8 pp 102ndash114 2002
[4] W R Heinzelman A Chandrakasan and H BalakrishnanldquoEnergy-efficient communication protocol for wirelessmicrosensor networksrdquo in Proceedings of the 33rd HawaiiIntentional Conference on System Sciences Maui HI USAJanuary 2000
[5] D Mehta and S Saxena ldquoA comparative analysis of energyefficient hierarchical routing protocols for wireless sensornetworksrdquo in Proceedings of the 2018 4th InternationalConference on Computing Sciences (ICCS) pp 53ndash58Jalandhar India August 2018
[6] C Karlof and D Wagner ldquoSecure routing in wireless sensornetworks attacks and countermeasuresrdquo Ad Hoc Networksvol 1 2003
[7] L B Oliveira A Ferreira M A Vilaca et al ldquoSecLEACH-onthe security of clustered sensor networksrdquo Signal Processingvol 87 2007
[8] Y Y Gu GW Bai and J J Tao ldquoAZM-LEACH autonomouszone-based multi-hop routing protocol in WSNsrdquo ComputerEngineering and Applications vol 47 no 20 pp 58ndash61 2011
[9] L XWang Research on Routing Technology ofWireless SensorNetworks Based on Data Aggregation Shenyang LigongUniversity Shenyang China 2015
[10] J P Shao Research on Key Energy-Efficient Routing Tech-nology of WSN Based on Cluster Shenyang Ligong UniversityShenyang China 2015
[11] V K Arora V Sharma and M Sachdeva ldquoA survey onLEACH and otherrsquos routing protocols in wireless sensornetworkrdquo Optik vol 127 no 16 pp 6590ndash6600 2016
[12] W B Heinzelman A P Chandrakasan and H BalakrishnanldquoAn application-specific protocol architecture for wirelessmicrosensor networksrdquo IEEE Transactions on WirelessCommunications vol 1 no 4 pp 660ndash670 2002
[13] S Al-Sodairi and R Ouni ldquoReliable and energy-efficientmulti-hop LEACH-based clustering protocol for wirelesssensor networksrdquo Sustainable Computing Informatics andSystems vol 20 pp 1ndash13 2018
[14] O Younis and S Fahmy ldquoHEED a hybrid energy-efficientdistributed clustering approach for ad hoc sensor networksrdquo
IEEE Transactions on Mobile Computing vol 3 no 4pp 366ndash379 2004
[15] B B Chen and Y L Shi ldquoWSN routing protocol based oncluster heads selection in regionsrdquo Computer Engineeringvol 37 no 19 pp 96ndash98 2011
[16] P Azada ldquoCluster head selection in wireless sensor networksunder fuzzy environmentrdquo ISRN Sensor Networks vol 2013Article ID 909086 8 pages 2013
[17] S Soro and W B Heinzelman ldquoCluster head election tech-niques for coverage preservation in wireless sensor networksrdquoAd Hoc Networks vol 7 no 5 pp 955ndash972 2009
[18] A akkar ldquoDEAL distance and energy based advancedleach protocolrdquo in Proceedings of the International Conferenceon Information and Communication Technology for IntelligentSystems pp 370ndash376 Ahmedabad India March 2017
[19] T Y Chang W N Liu Y Zhang and H Y Li ldquoOptimizedLEACH protocol based on distance and energy of clusterheadrdquo Journal of Hebei University (Natural Science Edition)vol 39 no 2 pp 194ndash200 2019
[20] P Mehra M Doja and B Alam ldquoStability enhancement inLEACH (SE-LEACH) for homogeneousWSNrdquo EAI EndorsedTransactions on Scalable Information Systems vol 6 no 20pp 1ndash9 2019
[21] G Smaragdakis I Matta and A Bestavros ldquoSEP a stableelection protocol for clustered heterogeneous wireless sensornetworksrdquo in Proceedings of the Second InternationalWorkshop on Sensor and Actor Network Protocols and Ap-plications (SANPA 2004) pp 1ndash11 Boston MA USA June2004
[22] F S Hu and Q Xiao ldquoMulti-hop routing algorithm of energy-balancing based on LEACHrdquo Journal of Chinese ComputerSystems vol 35 no 1 pp 72ndash75 2014
[23] C F Li M Ye G H Chen and J Wu ldquoAn energy-efficientunequal clustering mechanism for wireless sensor networksrdquoin Proceedings of the IEEE International Conference on MobileAdhoc and Sensor Systems Conference p 604 WashingtonDC USA November 2005
[24] E Alnawafa I Marghescu and MHT ldquoMulti-hop techniquefor the improvement of leach protocolrdquo in Proceedings of the2016 15th RoEduNet Conference Networking in Education andResearch pp 1ndash5 Bucharest Romania September 2016
[25] E Alnawafa and I Marghescu ldquoIMHT improved MHT-LEACH protocol for wireless sensor networksrdquo in Proceedingsof the 2017 8th International Conference on Information andCommunication Systems (ICICS) pp 246ndash251 Irbid JordanApril 2017
[26] J Y Huo Z Zhang and C Tao ldquoUsing IPv6 address ad-vantage to build Network Node of Field observation In-struments in cold and arid areasrdquo China Education Networkno 5 pp 45-46 2018
[27] L Mateu and F Moll ldquoReview of energy harvesting tech-niques and applications for microelectronicsrdquo in Proceedingsof the International Society for Optical Engineering pp 359ndash373 Bellingham WA USA October 2005
[28] G Wang and R Y Wang ldquoRouting algorithm based oncluster-head optimization for self-energized wireless sensornetworkrdquo Journal of Computer Applications vol 38 no 334pp 201ndash216 2018
[29] X P Fan X Yang S Q Liu and Z H Qu ldquoClusteringrouting algorithm for wireless sensor networks with powerharvestingrdquo Computer Engineering vol 39 no 11 pp 126ndash134 2008
18 Journal of Electrical and Computer Engineering
[30] C H Zhang ldquoStudy on the energy heterogeneous clusteringrouting protocol for wireless sensor networksrdquo Science ampTechnology Vision no 13 pp 71+164ndash165 2012
[31] T Liu and F Li ldquoPower-efficient clustering routing protocolbased on applications in wireless sensor networkrdquo in Pro-ceedings of the International Conference on Wireless Com-munications IEEE Press Melbourne Australia September2009
Journal of Electrical and Computer Engineering 19
ABC
0
1
2
3
4
5
6
7Co
mpa
rison
of C
Hs i
n ea
ch re
gion
2 3 4 5 6 7 8 9 101Number of rounds
(a)
0
2
4
6
8
10
12
14
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(d)
0
5
10
15
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 11 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol without power supply
Journal of Electrical and Computer Engineering 13
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
2000
4000
6000
8000
10000
12000
Pack
ets t
o BS
LEACHSEP
PECRPImproved protocol
Figure 12 Comparison of packets sent to BS from CHs without power supply
times104
200
400
600
800
1000
1200
2000
1800
21000
1400
1600
Number of rounds
0
2
4
6
8
10
12
Pack
ets t
o CH
LEACHSEP
PECRPImproved protocol
Figure 13 Comparison of packets sent to CHs from member nodes without power supply
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
LEACHSEP
PECRPImproved protocol
Figure 14 Comparison of live nodes in each round with power supply
14 Journal of Electrical and Computer Engineering
Table 4 Statistics number of rounds of dead nodes of the four protocols with power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 177 204 232 341SEP 185 210 264 665PECRP 392 430 493 530FOI-LEACH 555 716 1238 2246
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
002
004
006
008
01
012
014
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 15 Comparison of average residual energy in each round with power supply
Table 5 Statistics of the average residual energy (J) of nodes of the four protocols with power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0086 0018 0 0SEP 0105 0036 0001 0PECRP 0099 007 0 0FOI-LEACH 0124 0109 0062 0001
0
1
2
3
4
5
6
7
8
Com
paris
on o
f CH
s in
each
regi
on
2 3 4 5 6 7 8 9 101Number of rounds
ABC
(a)
0
2
4
6
8
10
12
1415
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
Figure 16 Continued
Journal of Electrical and Computer Engineering 15
0
2
4
6
8
10
12
14
16N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14
16
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(d)
0
2
4
6
8
10
12
14
16
18
20
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 16 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol with power supply
0
2000
4000
6000
8000
10000
12000
14000
Pack
ets t
o BS
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 17 Comparison of packets sent to BS from CHs with power supply
16 Journal of Electrical and Computer Engineering
node e supplied energy promotes the extension of thenetwork lifetime and the stability of the networking for thefour protocols in varying degrees For the LEACH protocolthe node began to die at round 177 SEP protocol at round185 PECRP protocol at round 392 and round 555 for theimproved FOI-LEACH protocol
e distributions of the number of clusters in the fourprotocols with energy supply simulated for 10 rounds ofrandom elections are shown in Figure 16 Like the previousfigures Figure 16(a) represents the statistics number of CHsof each zone of FOI-LEACH protocol Figures 16(b)ndash16(e)represent the statistics number of CHs of FOI-LEACHprotocol LEACH protocol SEP protocol and PECRPprotocol respectively Due to the efficient schemes of CHselecting and clustering the FOI-LEACH protocol showssignificantly better performance than the other threeprotocols
(4) Network (roughput In the environment of self-energyas shown in Figure 17 the total number of packets sent toBS of the LEACH protocol SEP protocol PECRP protocoland the proposed FOI-LEACH protocol is approximately2428 3080 3746 and 13265 respectively Moreover inFigure 18 the total number of packages sent to CHs of theLEACH protocol SEP protocol PECRP protocol andFOI-LEACH protocol is approximately 21400 2430044000 and 123200 respectively We can find that the totalnumber of packets sent by our protocol to BS and CHs ismuch higher than the other protocols which also dem-onstrated that the proposed protocol has a better networkthroughout
6 Conclusions
According to the characteristics of field observation in-strument networking an improved protocol FOI-LEACHbased on LEACH protocol was proposed in this paper Byconsidering the energy factor in the CH election threshold
and referring to the SEP protocol to set up two kinds ofnodes with different initial energies which are calledadvanced nodes and normal nodes the network model offield observation instruments has been established Inaddition to solve the problem that the LEACH protocolconsumes much energy during transmission and results inuneven energy consumption for the direct and long-distance transmission the improved protocol adopted the3 zones of partitioning mechanism and the multihoptransmission mechanism to alleviate and avoid the ldquohotspotrdquo problems Furthermore energy supplies were addedto the nodes in A and B zones that are responsible formore energy transmission so as to balance the energyconsumption of the network and prolong the networklifetime In the simulation experiments we compared theperformance of the FOI-LEACH protocol with theLEACH SEP and PECRP protocols in two cases with orwithout energy supply Comparing performance indica-tors of network lifetime energy consumption rate sta-bility and network throughput the proposed FOI-LEACH protocol can slow down the death of nodes andthe energy consumption rate obviously and shows asignificantly better performance than other three proto-cols e experimental results demonstrated that the FOI-LEACH protocol could balance network energy con-sumption and alleviate the ldquohot spotrdquo problem to extendthe lifetime of network nodes in the field observationinstruments network e future work is to implementand port the improved protocol to the hardware of net-working node we designed and developed previously andtest and verify the feasibility and stability of the protocolin the actual situation
Data Availability
e initial nodes are generated randomly in the networkand there are no observation data used in the simulationexperiments
0
20000
40000
60000
80000
100000
120000
140000
Pack
ets t
o CH
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 18 Comparison of packets sent to CHs from nodes with power supply
Journal of Electrical and Computer Engineering 17
Conflicts of Interest
e authors declare that there are no conflicts of interest
Acknowledgments
is work was supported by the National Nature ScienceFoundation of China (Grant no 61862038) the LanzhouTalent Innovation and Entrepreneurship Technology PlanProject (no 2019-RC-14) and the Foundation of a HundredYouth Talents Training Program of Lanzhou JiaotongUniversity
References
[1] J Y Huo Z N Ren and Y R Yang A Kind of InstrumentNetwork Node Equipment and Monitoring System ChinesePatents Beijing China 2017
[2] J Y Huo Key Technology and Application Research ofE-Science Virtual Joint Observation System for Geoscience inCold and Dry Regions University of Chinese Academy ofSciences Beijing China 2012
[3] I F Akyildiz W L Weilian Su Y Sankarasubramaniam andE Cayirci ldquoA survey on sensor networksrdquo IEEE Communi-cations Magazine vol 40 no 8 pp 102ndash114 2002
[4] W R Heinzelman A Chandrakasan and H BalakrishnanldquoEnergy-efficient communication protocol for wirelessmicrosensor networksrdquo in Proceedings of the 33rd HawaiiIntentional Conference on System Sciences Maui HI USAJanuary 2000
[5] D Mehta and S Saxena ldquoA comparative analysis of energyefficient hierarchical routing protocols for wireless sensornetworksrdquo in Proceedings of the 2018 4th InternationalConference on Computing Sciences (ICCS) pp 53ndash58Jalandhar India August 2018
[6] C Karlof and D Wagner ldquoSecure routing in wireless sensornetworks attacks and countermeasuresrdquo Ad Hoc Networksvol 1 2003
[7] L B Oliveira A Ferreira M A Vilaca et al ldquoSecLEACH-onthe security of clustered sensor networksrdquo Signal Processingvol 87 2007
[8] Y Y Gu GW Bai and J J Tao ldquoAZM-LEACH autonomouszone-based multi-hop routing protocol in WSNsrdquo ComputerEngineering and Applications vol 47 no 20 pp 58ndash61 2011
[9] L XWang Research on Routing Technology ofWireless SensorNetworks Based on Data Aggregation Shenyang LigongUniversity Shenyang China 2015
[10] J P Shao Research on Key Energy-Efficient Routing Tech-nology of WSN Based on Cluster Shenyang Ligong UniversityShenyang China 2015
[11] V K Arora V Sharma and M Sachdeva ldquoA survey onLEACH and otherrsquos routing protocols in wireless sensornetworkrdquo Optik vol 127 no 16 pp 6590ndash6600 2016
[12] W B Heinzelman A P Chandrakasan and H BalakrishnanldquoAn application-specific protocol architecture for wirelessmicrosensor networksrdquo IEEE Transactions on WirelessCommunications vol 1 no 4 pp 660ndash670 2002
[13] S Al-Sodairi and R Ouni ldquoReliable and energy-efficientmulti-hop LEACH-based clustering protocol for wirelesssensor networksrdquo Sustainable Computing Informatics andSystems vol 20 pp 1ndash13 2018
[14] O Younis and S Fahmy ldquoHEED a hybrid energy-efficientdistributed clustering approach for ad hoc sensor networksrdquo
IEEE Transactions on Mobile Computing vol 3 no 4pp 366ndash379 2004
[15] B B Chen and Y L Shi ldquoWSN routing protocol based oncluster heads selection in regionsrdquo Computer Engineeringvol 37 no 19 pp 96ndash98 2011
[16] P Azada ldquoCluster head selection in wireless sensor networksunder fuzzy environmentrdquo ISRN Sensor Networks vol 2013Article ID 909086 8 pages 2013
[17] S Soro and W B Heinzelman ldquoCluster head election tech-niques for coverage preservation in wireless sensor networksrdquoAd Hoc Networks vol 7 no 5 pp 955ndash972 2009
[18] A akkar ldquoDEAL distance and energy based advancedleach protocolrdquo in Proceedings of the International Conferenceon Information and Communication Technology for IntelligentSystems pp 370ndash376 Ahmedabad India March 2017
[19] T Y Chang W N Liu Y Zhang and H Y Li ldquoOptimizedLEACH protocol based on distance and energy of clusterheadrdquo Journal of Hebei University (Natural Science Edition)vol 39 no 2 pp 194ndash200 2019
[20] P Mehra M Doja and B Alam ldquoStability enhancement inLEACH (SE-LEACH) for homogeneousWSNrdquo EAI EndorsedTransactions on Scalable Information Systems vol 6 no 20pp 1ndash9 2019
[21] G Smaragdakis I Matta and A Bestavros ldquoSEP a stableelection protocol for clustered heterogeneous wireless sensornetworksrdquo in Proceedings of the Second InternationalWorkshop on Sensor and Actor Network Protocols and Ap-plications (SANPA 2004) pp 1ndash11 Boston MA USA June2004
[22] F S Hu and Q Xiao ldquoMulti-hop routing algorithm of energy-balancing based on LEACHrdquo Journal of Chinese ComputerSystems vol 35 no 1 pp 72ndash75 2014
[23] C F Li M Ye G H Chen and J Wu ldquoAn energy-efficientunequal clustering mechanism for wireless sensor networksrdquoin Proceedings of the IEEE International Conference on MobileAdhoc and Sensor Systems Conference p 604 WashingtonDC USA November 2005
[24] E Alnawafa I Marghescu and MHT ldquoMulti-hop techniquefor the improvement of leach protocolrdquo in Proceedings of the2016 15th RoEduNet Conference Networking in Education andResearch pp 1ndash5 Bucharest Romania September 2016
[25] E Alnawafa and I Marghescu ldquoIMHT improved MHT-LEACH protocol for wireless sensor networksrdquo in Proceedingsof the 2017 8th International Conference on Information andCommunication Systems (ICICS) pp 246ndash251 Irbid JordanApril 2017
[26] J Y Huo Z Zhang and C Tao ldquoUsing IPv6 address ad-vantage to build Network Node of Field observation In-struments in cold and arid areasrdquo China Education Networkno 5 pp 45-46 2018
[27] L Mateu and F Moll ldquoReview of energy harvesting tech-niques and applications for microelectronicsrdquo in Proceedingsof the International Society for Optical Engineering pp 359ndash373 Bellingham WA USA October 2005
[28] G Wang and R Y Wang ldquoRouting algorithm based oncluster-head optimization for self-energized wireless sensornetworkrdquo Journal of Computer Applications vol 38 no 334pp 201ndash216 2018
[29] X P Fan X Yang S Q Liu and Z H Qu ldquoClusteringrouting algorithm for wireless sensor networks with powerharvestingrdquo Computer Engineering vol 39 no 11 pp 126ndash134 2008
18 Journal of Electrical and Computer Engineering
[30] C H Zhang ldquoStudy on the energy heterogeneous clusteringrouting protocol for wireless sensor networksrdquo Science ampTechnology Vision no 13 pp 71+164ndash165 2012
[31] T Liu and F Li ldquoPower-efficient clustering routing protocolbased on applications in wireless sensor networkrdquo in Pro-ceedings of the International Conference on Wireless Com-munications IEEE Press Melbourne Australia September2009
Journal of Electrical and Computer Engineering 19
200
400
600
800
1000
1200
1400
1600
1800
2000
21000
Number of rounds
0
2000
4000
6000
8000
10000
12000
Pack
ets t
o BS
LEACHSEP
PECRPImproved protocol
Figure 12 Comparison of packets sent to BS from CHs without power supply
times104
200
400
600
800
1000
1200
2000
1800
21000
1400
1600
Number of rounds
0
2
4
6
8
10
12
Pack
ets t
o CH
LEACHSEP
PECRPImproved protocol
Figure 13 Comparison of packets sent to CHs from member nodes without power supply
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
10
20
30
40
50
60
70
80
90
100
Num
ber o
f aliv
e nod
es
LEACHSEP
PECRPImproved protocol
Figure 14 Comparison of live nodes in each round with power supply
14 Journal of Electrical and Computer Engineering
Table 4 Statistics number of rounds of dead nodes of the four protocols with power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 177 204 232 341SEP 185 210 264 665PECRP 392 430 493 530FOI-LEACH 555 716 1238 2246
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
002
004
006
008
01
012
014
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 15 Comparison of average residual energy in each round with power supply
Table 5 Statistics of the average residual energy (J) of nodes of the four protocols with power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0086 0018 0 0SEP 0105 0036 0001 0PECRP 0099 007 0 0FOI-LEACH 0124 0109 0062 0001
0
1
2
3
4
5
6
7
8
Com
paris
on o
f CH
s in
each
regi
on
2 3 4 5 6 7 8 9 101Number of rounds
ABC
(a)
0
2
4
6
8
10
12
1415
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
Figure 16 Continued
Journal of Electrical and Computer Engineering 15
0
2
4
6
8
10
12
14
16N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14
16
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(d)
0
2
4
6
8
10
12
14
16
18
20
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 16 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol with power supply
0
2000
4000
6000
8000
10000
12000
14000
Pack
ets t
o BS
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 17 Comparison of packets sent to BS from CHs with power supply
16 Journal of Electrical and Computer Engineering
node e supplied energy promotes the extension of thenetwork lifetime and the stability of the networking for thefour protocols in varying degrees For the LEACH protocolthe node began to die at round 177 SEP protocol at round185 PECRP protocol at round 392 and round 555 for theimproved FOI-LEACH protocol
e distributions of the number of clusters in the fourprotocols with energy supply simulated for 10 rounds ofrandom elections are shown in Figure 16 Like the previousfigures Figure 16(a) represents the statistics number of CHsof each zone of FOI-LEACH protocol Figures 16(b)ndash16(e)represent the statistics number of CHs of FOI-LEACHprotocol LEACH protocol SEP protocol and PECRPprotocol respectively Due to the efficient schemes of CHselecting and clustering the FOI-LEACH protocol showssignificantly better performance than the other threeprotocols
(4) Network (roughput In the environment of self-energyas shown in Figure 17 the total number of packets sent toBS of the LEACH protocol SEP protocol PECRP protocoland the proposed FOI-LEACH protocol is approximately2428 3080 3746 and 13265 respectively Moreover inFigure 18 the total number of packages sent to CHs of theLEACH protocol SEP protocol PECRP protocol andFOI-LEACH protocol is approximately 21400 2430044000 and 123200 respectively We can find that the totalnumber of packets sent by our protocol to BS and CHs ismuch higher than the other protocols which also dem-onstrated that the proposed protocol has a better networkthroughout
6 Conclusions
According to the characteristics of field observation in-strument networking an improved protocol FOI-LEACHbased on LEACH protocol was proposed in this paper Byconsidering the energy factor in the CH election threshold
and referring to the SEP protocol to set up two kinds ofnodes with different initial energies which are calledadvanced nodes and normal nodes the network model offield observation instruments has been established Inaddition to solve the problem that the LEACH protocolconsumes much energy during transmission and results inuneven energy consumption for the direct and long-distance transmission the improved protocol adopted the3 zones of partitioning mechanism and the multihoptransmission mechanism to alleviate and avoid the ldquohotspotrdquo problems Furthermore energy supplies were addedto the nodes in A and B zones that are responsible formore energy transmission so as to balance the energyconsumption of the network and prolong the networklifetime In the simulation experiments we compared theperformance of the FOI-LEACH protocol with theLEACH SEP and PECRP protocols in two cases with orwithout energy supply Comparing performance indica-tors of network lifetime energy consumption rate sta-bility and network throughput the proposed FOI-LEACH protocol can slow down the death of nodes andthe energy consumption rate obviously and shows asignificantly better performance than other three proto-cols e experimental results demonstrated that the FOI-LEACH protocol could balance network energy con-sumption and alleviate the ldquohot spotrdquo problem to extendthe lifetime of network nodes in the field observationinstruments network e future work is to implementand port the improved protocol to the hardware of net-working node we designed and developed previously andtest and verify the feasibility and stability of the protocolin the actual situation
Data Availability
e initial nodes are generated randomly in the networkand there are no observation data used in the simulationexperiments
0
20000
40000
60000
80000
100000
120000
140000
Pack
ets t
o CH
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 18 Comparison of packets sent to CHs from nodes with power supply
Journal of Electrical and Computer Engineering 17
Conflicts of Interest
e authors declare that there are no conflicts of interest
Acknowledgments
is work was supported by the National Nature ScienceFoundation of China (Grant no 61862038) the LanzhouTalent Innovation and Entrepreneurship Technology PlanProject (no 2019-RC-14) and the Foundation of a HundredYouth Talents Training Program of Lanzhou JiaotongUniversity
References
[1] J Y Huo Z N Ren and Y R Yang A Kind of InstrumentNetwork Node Equipment and Monitoring System ChinesePatents Beijing China 2017
[2] J Y Huo Key Technology and Application Research ofE-Science Virtual Joint Observation System for Geoscience inCold and Dry Regions University of Chinese Academy ofSciences Beijing China 2012
[3] I F Akyildiz W L Weilian Su Y Sankarasubramaniam andE Cayirci ldquoA survey on sensor networksrdquo IEEE Communi-cations Magazine vol 40 no 8 pp 102ndash114 2002
[4] W R Heinzelman A Chandrakasan and H BalakrishnanldquoEnergy-efficient communication protocol for wirelessmicrosensor networksrdquo in Proceedings of the 33rd HawaiiIntentional Conference on System Sciences Maui HI USAJanuary 2000
[5] D Mehta and S Saxena ldquoA comparative analysis of energyefficient hierarchical routing protocols for wireless sensornetworksrdquo in Proceedings of the 2018 4th InternationalConference on Computing Sciences (ICCS) pp 53ndash58Jalandhar India August 2018
[6] C Karlof and D Wagner ldquoSecure routing in wireless sensornetworks attacks and countermeasuresrdquo Ad Hoc Networksvol 1 2003
[7] L B Oliveira A Ferreira M A Vilaca et al ldquoSecLEACH-onthe security of clustered sensor networksrdquo Signal Processingvol 87 2007
[8] Y Y Gu GW Bai and J J Tao ldquoAZM-LEACH autonomouszone-based multi-hop routing protocol in WSNsrdquo ComputerEngineering and Applications vol 47 no 20 pp 58ndash61 2011
[9] L XWang Research on Routing Technology ofWireless SensorNetworks Based on Data Aggregation Shenyang LigongUniversity Shenyang China 2015
[10] J P Shao Research on Key Energy-Efficient Routing Tech-nology of WSN Based on Cluster Shenyang Ligong UniversityShenyang China 2015
[11] V K Arora V Sharma and M Sachdeva ldquoA survey onLEACH and otherrsquos routing protocols in wireless sensornetworkrdquo Optik vol 127 no 16 pp 6590ndash6600 2016
[12] W B Heinzelman A P Chandrakasan and H BalakrishnanldquoAn application-specific protocol architecture for wirelessmicrosensor networksrdquo IEEE Transactions on WirelessCommunications vol 1 no 4 pp 660ndash670 2002
[13] S Al-Sodairi and R Ouni ldquoReliable and energy-efficientmulti-hop LEACH-based clustering protocol for wirelesssensor networksrdquo Sustainable Computing Informatics andSystems vol 20 pp 1ndash13 2018
[14] O Younis and S Fahmy ldquoHEED a hybrid energy-efficientdistributed clustering approach for ad hoc sensor networksrdquo
IEEE Transactions on Mobile Computing vol 3 no 4pp 366ndash379 2004
[15] B B Chen and Y L Shi ldquoWSN routing protocol based oncluster heads selection in regionsrdquo Computer Engineeringvol 37 no 19 pp 96ndash98 2011
[16] P Azada ldquoCluster head selection in wireless sensor networksunder fuzzy environmentrdquo ISRN Sensor Networks vol 2013Article ID 909086 8 pages 2013
[17] S Soro and W B Heinzelman ldquoCluster head election tech-niques for coverage preservation in wireless sensor networksrdquoAd Hoc Networks vol 7 no 5 pp 955ndash972 2009
[18] A akkar ldquoDEAL distance and energy based advancedleach protocolrdquo in Proceedings of the International Conferenceon Information and Communication Technology for IntelligentSystems pp 370ndash376 Ahmedabad India March 2017
[19] T Y Chang W N Liu Y Zhang and H Y Li ldquoOptimizedLEACH protocol based on distance and energy of clusterheadrdquo Journal of Hebei University (Natural Science Edition)vol 39 no 2 pp 194ndash200 2019
[20] P Mehra M Doja and B Alam ldquoStability enhancement inLEACH (SE-LEACH) for homogeneousWSNrdquo EAI EndorsedTransactions on Scalable Information Systems vol 6 no 20pp 1ndash9 2019
[21] G Smaragdakis I Matta and A Bestavros ldquoSEP a stableelection protocol for clustered heterogeneous wireless sensornetworksrdquo in Proceedings of the Second InternationalWorkshop on Sensor and Actor Network Protocols and Ap-plications (SANPA 2004) pp 1ndash11 Boston MA USA June2004
[22] F S Hu and Q Xiao ldquoMulti-hop routing algorithm of energy-balancing based on LEACHrdquo Journal of Chinese ComputerSystems vol 35 no 1 pp 72ndash75 2014
[23] C F Li M Ye G H Chen and J Wu ldquoAn energy-efficientunequal clustering mechanism for wireless sensor networksrdquoin Proceedings of the IEEE International Conference on MobileAdhoc and Sensor Systems Conference p 604 WashingtonDC USA November 2005
[24] E Alnawafa I Marghescu and MHT ldquoMulti-hop techniquefor the improvement of leach protocolrdquo in Proceedings of the2016 15th RoEduNet Conference Networking in Education andResearch pp 1ndash5 Bucharest Romania September 2016
[25] E Alnawafa and I Marghescu ldquoIMHT improved MHT-LEACH protocol for wireless sensor networksrdquo in Proceedingsof the 2017 8th International Conference on Information andCommunication Systems (ICICS) pp 246ndash251 Irbid JordanApril 2017
[26] J Y Huo Z Zhang and C Tao ldquoUsing IPv6 address ad-vantage to build Network Node of Field observation In-struments in cold and arid areasrdquo China Education Networkno 5 pp 45-46 2018
[27] L Mateu and F Moll ldquoReview of energy harvesting tech-niques and applications for microelectronicsrdquo in Proceedingsof the International Society for Optical Engineering pp 359ndash373 Bellingham WA USA October 2005
[28] G Wang and R Y Wang ldquoRouting algorithm based oncluster-head optimization for self-energized wireless sensornetworkrdquo Journal of Computer Applications vol 38 no 334pp 201ndash216 2018
[29] X P Fan X Yang S Q Liu and Z H Qu ldquoClusteringrouting algorithm for wireless sensor networks with powerharvestingrdquo Computer Engineering vol 39 no 11 pp 126ndash134 2008
18 Journal of Electrical and Computer Engineering
[30] C H Zhang ldquoStudy on the energy heterogeneous clusteringrouting protocol for wireless sensor networksrdquo Science ampTechnology Vision no 13 pp 71+164ndash165 2012
[31] T Liu and F Li ldquoPower-efficient clustering routing protocolbased on applications in wireless sensor networkrdquo in Pro-ceedings of the International Conference on Wireless Com-munications IEEE Press Melbourne Australia September2009
Journal of Electrical and Computer Engineering 19
Table 4 Statistics number of rounds of dead nodes of the four protocols with power supply
Protocol First node dies 10 of nodes die 50 of nodes die 100 of nodes dieLEACH 177 204 232 341SEP 185 210 264 665PECRP 392 430 493 530FOI-LEACH 555 716 1238 2246
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
23000
Number of rounds
0
002
004
006
008
01
012
014
Ave
rage
ener
gy d
issip
atio
n ev
ery
roun
d
LEACHSEP
PECRPImproved protocol
Figure 15 Comparison of average residual energy in each round with power supply
Table 5 Statistics of the average residual energy (J) of nodes of the four protocols with power supply
Protocol 50 rounds 200 rounds 600 rounds 2000 roundsLEACH 0086 0018 0 0SEP 0105 0036 0001 0PECRP 0099 007 0 0FOI-LEACH 0124 0109 0062 0001
0
1
2
3
4
5
6
7
8
Com
paris
on o
f CH
s in
each
regi
on
2 3 4 5 6 7 8 9 101Number of rounds
ABC
(a)
0
2
4
6
8
10
12
1415
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(b)
Figure 16 Continued
Journal of Electrical and Computer Engineering 15
0
2
4
6
8
10
12
14
16N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14
16
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(d)
0
2
4
6
8
10
12
14
16
18
20
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 16 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol with power supply
0
2000
4000
6000
8000
10000
12000
14000
Pack
ets t
o BS
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 17 Comparison of packets sent to BS from CHs with power supply
16 Journal of Electrical and Computer Engineering
node e supplied energy promotes the extension of thenetwork lifetime and the stability of the networking for thefour protocols in varying degrees For the LEACH protocolthe node began to die at round 177 SEP protocol at round185 PECRP protocol at round 392 and round 555 for theimproved FOI-LEACH protocol
e distributions of the number of clusters in the fourprotocols with energy supply simulated for 10 rounds ofrandom elections are shown in Figure 16 Like the previousfigures Figure 16(a) represents the statistics number of CHsof each zone of FOI-LEACH protocol Figures 16(b)ndash16(e)represent the statistics number of CHs of FOI-LEACHprotocol LEACH protocol SEP protocol and PECRPprotocol respectively Due to the efficient schemes of CHselecting and clustering the FOI-LEACH protocol showssignificantly better performance than the other threeprotocols
(4) Network (roughput In the environment of self-energyas shown in Figure 17 the total number of packets sent toBS of the LEACH protocol SEP protocol PECRP protocoland the proposed FOI-LEACH protocol is approximately2428 3080 3746 and 13265 respectively Moreover inFigure 18 the total number of packages sent to CHs of theLEACH protocol SEP protocol PECRP protocol andFOI-LEACH protocol is approximately 21400 2430044000 and 123200 respectively We can find that the totalnumber of packets sent by our protocol to BS and CHs ismuch higher than the other protocols which also dem-onstrated that the proposed protocol has a better networkthroughout
6 Conclusions
According to the characteristics of field observation in-strument networking an improved protocol FOI-LEACHbased on LEACH protocol was proposed in this paper Byconsidering the energy factor in the CH election threshold
and referring to the SEP protocol to set up two kinds ofnodes with different initial energies which are calledadvanced nodes and normal nodes the network model offield observation instruments has been established Inaddition to solve the problem that the LEACH protocolconsumes much energy during transmission and results inuneven energy consumption for the direct and long-distance transmission the improved protocol adopted the3 zones of partitioning mechanism and the multihoptransmission mechanism to alleviate and avoid the ldquohotspotrdquo problems Furthermore energy supplies were addedto the nodes in A and B zones that are responsible formore energy transmission so as to balance the energyconsumption of the network and prolong the networklifetime In the simulation experiments we compared theperformance of the FOI-LEACH protocol with theLEACH SEP and PECRP protocols in two cases with orwithout energy supply Comparing performance indica-tors of network lifetime energy consumption rate sta-bility and network throughput the proposed FOI-LEACH protocol can slow down the death of nodes andthe energy consumption rate obviously and shows asignificantly better performance than other three proto-cols e experimental results demonstrated that the FOI-LEACH protocol could balance network energy con-sumption and alleviate the ldquohot spotrdquo problem to extendthe lifetime of network nodes in the field observationinstruments network e future work is to implementand port the improved protocol to the hardware of net-working node we designed and developed previously andtest and verify the feasibility and stability of the protocolin the actual situation
Data Availability
e initial nodes are generated randomly in the networkand there are no observation data used in the simulationexperiments
0
20000
40000
60000
80000
100000
120000
140000
Pack
ets t
o CH
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 18 Comparison of packets sent to CHs from nodes with power supply
Journal of Electrical and Computer Engineering 17
Conflicts of Interest
e authors declare that there are no conflicts of interest
Acknowledgments
is work was supported by the National Nature ScienceFoundation of China (Grant no 61862038) the LanzhouTalent Innovation and Entrepreneurship Technology PlanProject (no 2019-RC-14) and the Foundation of a HundredYouth Talents Training Program of Lanzhou JiaotongUniversity
References
[1] J Y Huo Z N Ren and Y R Yang A Kind of InstrumentNetwork Node Equipment and Monitoring System ChinesePatents Beijing China 2017
[2] J Y Huo Key Technology and Application Research ofE-Science Virtual Joint Observation System for Geoscience inCold and Dry Regions University of Chinese Academy ofSciences Beijing China 2012
[3] I F Akyildiz W L Weilian Su Y Sankarasubramaniam andE Cayirci ldquoA survey on sensor networksrdquo IEEE Communi-cations Magazine vol 40 no 8 pp 102ndash114 2002
[4] W R Heinzelman A Chandrakasan and H BalakrishnanldquoEnergy-efficient communication protocol for wirelessmicrosensor networksrdquo in Proceedings of the 33rd HawaiiIntentional Conference on System Sciences Maui HI USAJanuary 2000
[5] D Mehta and S Saxena ldquoA comparative analysis of energyefficient hierarchical routing protocols for wireless sensornetworksrdquo in Proceedings of the 2018 4th InternationalConference on Computing Sciences (ICCS) pp 53ndash58Jalandhar India August 2018
[6] C Karlof and D Wagner ldquoSecure routing in wireless sensornetworks attacks and countermeasuresrdquo Ad Hoc Networksvol 1 2003
[7] L B Oliveira A Ferreira M A Vilaca et al ldquoSecLEACH-onthe security of clustered sensor networksrdquo Signal Processingvol 87 2007
[8] Y Y Gu GW Bai and J J Tao ldquoAZM-LEACH autonomouszone-based multi-hop routing protocol in WSNsrdquo ComputerEngineering and Applications vol 47 no 20 pp 58ndash61 2011
[9] L XWang Research on Routing Technology ofWireless SensorNetworks Based on Data Aggregation Shenyang LigongUniversity Shenyang China 2015
[10] J P Shao Research on Key Energy-Efficient Routing Tech-nology of WSN Based on Cluster Shenyang Ligong UniversityShenyang China 2015
[11] V K Arora V Sharma and M Sachdeva ldquoA survey onLEACH and otherrsquos routing protocols in wireless sensornetworkrdquo Optik vol 127 no 16 pp 6590ndash6600 2016
[12] W B Heinzelman A P Chandrakasan and H BalakrishnanldquoAn application-specific protocol architecture for wirelessmicrosensor networksrdquo IEEE Transactions on WirelessCommunications vol 1 no 4 pp 660ndash670 2002
[13] S Al-Sodairi and R Ouni ldquoReliable and energy-efficientmulti-hop LEACH-based clustering protocol for wirelesssensor networksrdquo Sustainable Computing Informatics andSystems vol 20 pp 1ndash13 2018
[14] O Younis and S Fahmy ldquoHEED a hybrid energy-efficientdistributed clustering approach for ad hoc sensor networksrdquo
IEEE Transactions on Mobile Computing vol 3 no 4pp 366ndash379 2004
[15] B B Chen and Y L Shi ldquoWSN routing protocol based oncluster heads selection in regionsrdquo Computer Engineeringvol 37 no 19 pp 96ndash98 2011
[16] P Azada ldquoCluster head selection in wireless sensor networksunder fuzzy environmentrdquo ISRN Sensor Networks vol 2013Article ID 909086 8 pages 2013
[17] S Soro and W B Heinzelman ldquoCluster head election tech-niques for coverage preservation in wireless sensor networksrdquoAd Hoc Networks vol 7 no 5 pp 955ndash972 2009
[18] A akkar ldquoDEAL distance and energy based advancedleach protocolrdquo in Proceedings of the International Conferenceon Information and Communication Technology for IntelligentSystems pp 370ndash376 Ahmedabad India March 2017
[19] T Y Chang W N Liu Y Zhang and H Y Li ldquoOptimizedLEACH protocol based on distance and energy of clusterheadrdquo Journal of Hebei University (Natural Science Edition)vol 39 no 2 pp 194ndash200 2019
[20] P Mehra M Doja and B Alam ldquoStability enhancement inLEACH (SE-LEACH) for homogeneousWSNrdquo EAI EndorsedTransactions on Scalable Information Systems vol 6 no 20pp 1ndash9 2019
[21] G Smaragdakis I Matta and A Bestavros ldquoSEP a stableelection protocol for clustered heterogeneous wireless sensornetworksrdquo in Proceedings of the Second InternationalWorkshop on Sensor and Actor Network Protocols and Ap-plications (SANPA 2004) pp 1ndash11 Boston MA USA June2004
[22] F S Hu and Q Xiao ldquoMulti-hop routing algorithm of energy-balancing based on LEACHrdquo Journal of Chinese ComputerSystems vol 35 no 1 pp 72ndash75 2014
[23] C F Li M Ye G H Chen and J Wu ldquoAn energy-efficientunequal clustering mechanism for wireless sensor networksrdquoin Proceedings of the IEEE International Conference on MobileAdhoc and Sensor Systems Conference p 604 WashingtonDC USA November 2005
[24] E Alnawafa I Marghescu and MHT ldquoMulti-hop techniquefor the improvement of leach protocolrdquo in Proceedings of the2016 15th RoEduNet Conference Networking in Education andResearch pp 1ndash5 Bucharest Romania September 2016
[25] E Alnawafa and I Marghescu ldquoIMHT improved MHT-LEACH protocol for wireless sensor networksrdquo in Proceedingsof the 2017 8th International Conference on Information andCommunication Systems (ICICS) pp 246ndash251 Irbid JordanApril 2017
[26] J Y Huo Z Zhang and C Tao ldquoUsing IPv6 address ad-vantage to build Network Node of Field observation In-struments in cold and arid areasrdquo China Education Networkno 5 pp 45-46 2018
[27] L Mateu and F Moll ldquoReview of energy harvesting tech-niques and applications for microelectronicsrdquo in Proceedingsof the International Society for Optical Engineering pp 359ndash373 Bellingham WA USA October 2005
[28] G Wang and R Y Wang ldquoRouting algorithm based oncluster-head optimization for self-energized wireless sensornetworkrdquo Journal of Computer Applications vol 38 no 334pp 201ndash216 2018
[29] X P Fan X Yang S Q Liu and Z H Qu ldquoClusteringrouting algorithm for wireless sensor networks with powerharvestingrdquo Computer Engineering vol 39 no 11 pp 126ndash134 2008
18 Journal of Electrical and Computer Engineering
[30] C H Zhang ldquoStudy on the energy heterogeneous clusteringrouting protocol for wireless sensor networksrdquo Science ampTechnology Vision no 13 pp 71+164ndash165 2012
[31] T Liu and F Li ldquoPower-efficient clustering routing protocolbased on applications in wireless sensor networkrdquo in Pro-ceedings of the International Conference on Wireless Com-munications IEEE Press Melbourne Australia September2009
Journal of Electrical and Computer Engineering 19
0
2
4
6
8
10
12
14
16N
umbe
r of C
Hs
2 4 6 8 10 120Number of rounds
(c)
0
2
4
6
8
10
12
14
16
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(d)
0
2
4
6
8
10
12
14
16
18
20
Num
ber o
f CH
s
2 4 6 8 10 120Number of rounds
(e)
Figure 16 Statistics of CHs (a) in each zone of FOI-LEACH protocol (b) of FOI-LEACH protocol (c) of LEACH protocol (d) of SEPprotocol and (e) of PECRP protocol with power supply
0
2000
4000
6000
8000
10000
12000
14000
Pack
ets t
o BS
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 17 Comparison of packets sent to BS from CHs with power supply
16 Journal of Electrical and Computer Engineering
node e supplied energy promotes the extension of thenetwork lifetime and the stability of the networking for thefour protocols in varying degrees For the LEACH protocolthe node began to die at round 177 SEP protocol at round185 PECRP protocol at round 392 and round 555 for theimproved FOI-LEACH protocol
e distributions of the number of clusters in the fourprotocols with energy supply simulated for 10 rounds ofrandom elections are shown in Figure 16 Like the previousfigures Figure 16(a) represents the statistics number of CHsof each zone of FOI-LEACH protocol Figures 16(b)ndash16(e)represent the statistics number of CHs of FOI-LEACHprotocol LEACH protocol SEP protocol and PECRPprotocol respectively Due to the efficient schemes of CHselecting and clustering the FOI-LEACH protocol showssignificantly better performance than the other threeprotocols
(4) Network (roughput In the environment of self-energyas shown in Figure 17 the total number of packets sent toBS of the LEACH protocol SEP protocol PECRP protocoland the proposed FOI-LEACH protocol is approximately2428 3080 3746 and 13265 respectively Moreover inFigure 18 the total number of packages sent to CHs of theLEACH protocol SEP protocol PECRP protocol andFOI-LEACH protocol is approximately 21400 2430044000 and 123200 respectively We can find that the totalnumber of packets sent by our protocol to BS and CHs ismuch higher than the other protocols which also dem-onstrated that the proposed protocol has a better networkthroughout
6 Conclusions
According to the characteristics of field observation in-strument networking an improved protocol FOI-LEACHbased on LEACH protocol was proposed in this paper Byconsidering the energy factor in the CH election threshold
and referring to the SEP protocol to set up two kinds ofnodes with different initial energies which are calledadvanced nodes and normal nodes the network model offield observation instruments has been established Inaddition to solve the problem that the LEACH protocolconsumes much energy during transmission and results inuneven energy consumption for the direct and long-distance transmission the improved protocol adopted the3 zones of partitioning mechanism and the multihoptransmission mechanism to alleviate and avoid the ldquohotspotrdquo problems Furthermore energy supplies were addedto the nodes in A and B zones that are responsible formore energy transmission so as to balance the energyconsumption of the network and prolong the networklifetime In the simulation experiments we compared theperformance of the FOI-LEACH protocol with theLEACH SEP and PECRP protocols in two cases with orwithout energy supply Comparing performance indica-tors of network lifetime energy consumption rate sta-bility and network throughput the proposed FOI-LEACH protocol can slow down the death of nodes andthe energy consumption rate obviously and shows asignificantly better performance than other three proto-cols e experimental results demonstrated that the FOI-LEACH protocol could balance network energy con-sumption and alleviate the ldquohot spotrdquo problem to extendthe lifetime of network nodes in the field observationinstruments network e future work is to implementand port the improved protocol to the hardware of net-working node we designed and developed previously andtest and verify the feasibility and stability of the protocolin the actual situation
Data Availability
e initial nodes are generated randomly in the networkand there are no observation data used in the simulationexperiments
0
20000
40000
60000
80000
100000
120000
140000
Pack
ets t
o CH
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 18 Comparison of packets sent to CHs from nodes with power supply
Journal of Electrical and Computer Engineering 17
Conflicts of Interest
e authors declare that there are no conflicts of interest
Acknowledgments
is work was supported by the National Nature ScienceFoundation of China (Grant no 61862038) the LanzhouTalent Innovation and Entrepreneurship Technology PlanProject (no 2019-RC-14) and the Foundation of a HundredYouth Talents Training Program of Lanzhou JiaotongUniversity
References
[1] J Y Huo Z N Ren and Y R Yang A Kind of InstrumentNetwork Node Equipment and Monitoring System ChinesePatents Beijing China 2017
[2] J Y Huo Key Technology and Application Research ofE-Science Virtual Joint Observation System for Geoscience inCold and Dry Regions University of Chinese Academy ofSciences Beijing China 2012
[3] I F Akyildiz W L Weilian Su Y Sankarasubramaniam andE Cayirci ldquoA survey on sensor networksrdquo IEEE Communi-cations Magazine vol 40 no 8 pp 102ndash114 2002
[4] W R Heinzelman A Chandrakasan and H BalakrishnanldquoEnergy-efficient communication protocol for wirelessmicrosensor networksrdquo in Proceedings of the 33rd HawaiiIntentional Conference on System Sciences Maui HI USAJanuary 2000
[5] D Mehta and S Saxena ldquoA comparative analysis of energyefficient hierarchical routing protocols for wireless sensornetworksrdquo in Proceedings of the 2018 4th InternationalConference on Computing Sciences (ICCS) pp 53ndash58Jalandhar India August 2018
[6] C Karlof and D Wagner ldquoSecure routing in wireless sensornetworks attacks and countermeasuresrdquo Ad Hoc Networksvol 1 2003
[7] L B Oliveira A Ferreira M A Vilaca et al ldquoSecLEACH-onthe security of clustered sensor networksrdquo Signal Processingvol 87 2007
[8] Y Y Gu GW Bai and J J Tao ldquoAZM-LEACH autonomouszone-based multi-hop routing protocol in WSNsrdquo ComputerEngineering and Applications vol 47 no 20 pp 58ndash61 2011
[9] L XWang Research on Routing Technology ofWireless SensorNetworks Based on Data Aggregation Shenyang LigongUniversity Shenyang China 2015
[10] J P Shao Research on Key Energy-Efficient Routing Tech-nology of WSN Based on Cluster Shenyang Ligong UniversityShenyang China 2015
[11] V K Arora V Sharma and M Sachdeva ldquoA survey onLEACH and otherrsquos routing protocols in wireless sensornetworkrdquo Optik vol 127 no 16 pp 6590ndash6600 2016
[12] W B Heinzelman A P Chandrakasan and H BalakrishnanldquoAn application-specific protocol architecture for wirelessmicrosensor networksrdquo IEEE Transactions on WirelessCommunications vol 1 no 4 pp 660ndash670 2002
[13] S Al-Sodairi and R Ouni ldquoReliable and energy-efficientmulti-hop LEACH-based clustering protocol for wirelesssensor networksrdquo Sustainable Computing Informatics andSystems vol 20 pp 1ndash13 2018
[14] O Younis and S Fahmy ldquoHEED a hybrid energy-efficientdistributed clustering approach for ad hoc sensor networksrdquo
IEEE Transactions on Mobile Computing vol 3 no 4pp 366ndash379 2004
[15] B B Chen and Y L Shi ldquoWSN routing protocol based oncluster heads selection in regionsrdquo Computer Engineeringvol 37 no 19 pp 96ndash98 2011
[16] P Azada ldquoCluster head selection in wireless sensor networksunder fuzzy environmentrdquo ISRN Sensor Networks vol 2013Article ID 909086 8 pages 2013
[17] S Soro and W B Heinzelman ldquoCluster head election tech-niques for coverage preservation in wireless sensor networksrdquoAd Hoc Networks vol 7 no 5 pp 955ndash972 2009
[18] A akkar ldquoDEAL distance and energy based advancedleach protocolrdquo in Proceedings of the International Conferenceon Information and Communication Technology for IntelligentSystems pp 370ndash376 Ahmedabad India March 2017
[19] T Y Chang W N Liu Y Zhang and H Y Li ldquoOptimizedLEACH protocol based on distance and energy of clusterheadrdquo Journal of Hebei University (Natural Science Edition)vol 39 no 2 pp 194ndash200 2019
[20] P Mehra M Doja and B Alam ldquoStability enhancement inLEACH (SE-LEACH) for homogeneousWSNrdquo EAI EndorsedTransactions on Scalable Information Systems vol 6 no 20pp 1ndash9 2019
[21] G Smaragdakis I Matta and A Bestavros ldquoSEP a stableelection protocol for clustered heterogeneous wireless sensornetworksrdquo in Proceedings of the Second InternationalWorkshop on Sensor and Actor Network Protocols and Ap-plications (SANPA 2004) pp 1ndash11 Boston MA USA June2004
[22] F S Hu and Q Xiao ldquoMulti-hop routing algorithm of energy-balancing based on LEACHrdquo Journal of Chinese ComputerSystems vol 35 no 1 pp 72ndash75 2014
[23] C F Li M Ye G H Chen and J Wu ldquoAn energy-efficientunequal clustering mechanism for wireless sensor networksrdquoin Proceedings of the IEEE International Conference on MobileAdhoc and Sensor Systems Conference p 604 WashingtonDC USA November 2005
[24] E Alnawafa I Marghescu and MHT ldquoMulti-hop techniquefor the improvement of leach protocolrdquo in Proceedings of the2016 15th RoEduNet Conference Networking in Education andResearch pp 1ndash5 Bucharest Romania September 2016
[25] E Alnawafa and I Marghescu ldquoIMHT improved MHT-LEACH protocol for wireless sensor networksrdquo in Proceedingsof the 2017 8th International Conference on Information andCommunication Systems (ICICS) pp 246ndash251 Irbid JordanApril 2017
[26] J Y Huo Z Zhang and C Tao ldquoUsing IPv6 address ad-vantage to build Network Node of Field observation In-struments in cold and arid areasrdquo China Education Networkno 5 pp 45-46 2018
[27] L Mateu and F Moll ldquoReview of energy harvesting tech-niques and applications for microelectronicsrdquo in Proceedingsof the International Society for Optical Engineering pp 359ndash373 Bellingham WA USA October 2005
[28] G Wang and R Y Wang ldquoRouting algorithm based oncluster-head optimization for self-energized wireless sensornetworkrdquo Journal of Computer Applications vol 38 no 334pp 201ndash216 2018
[29] X P Fan X Yang S Q Liu and Z H Qu ldquoClusteringrouting algorithm for wireless sensor networks with powerharvestingrdquo Computer Engineering vol 39 no 11 pp 126ndash134 2008
18 Journal of Electrical and Computer Engineering
[30] C H Zhang ldquoStudy on the energy heterogeneous clusteringrouting protocol for wireless sensor networksrdquo Science ampTechnology Vision no 13 pp 71+164ndash165 2012
[31] T Liu and F Li ldquoPower-efficient clustering routing protocolbased on applications in wireless sensor networkrdquo in Pro-ceedings of the International Conference on Wireless Com-munications IEEE Press Melbourne Australia September2009
Journal of Electrical and Computer Engineering 19
node e supplied energy promotes the extension of thenetwork lifetime and the stability of the networking for thefour protocols in varying degrees For the LEACH protocolthe node began to die at round 177 SEP protocol at round185 PECRP protocol at round 392 and round 555 for theimproved FOI-LEACH protocol
e distributions of the number of clusters in the fourprotocols with energy supply simulated for 10 rounds ofrandom elections are shown in Figure 16 Like the previousfigures Figure 16(a) represents the statistics number of CHsof each zone of FOI-LEACH protocol Figures 16(b)ndash16(e)represent the statistics number of CHs of FOI-LEACHprotocol LEACH protocol SEP protocol and PECRPprotocol respectively Due to the efficient schemes of CHselecting and clustering the FOI-LEACH protocol showssignificantly better performance than the other threeprotocols
(4) Network (roughput In the environment of self-energyas shown in Figure 17 the total number of packets sent toBS of the LEACH protocol SEP protocol PECRP protocoland the proposed FOI-LEACH protocol is approximately2428 3080 3746 and 13265 respectively Moreover inFigure 18 the total number of packages sent to CHs of theLEACH protocol SEP protocol PECRP protocol andFOI-LEACH protocol is approximately 21400 2430044000 and 123200 respectively We can find that the totalnumber of packets sent by our protocol to BS and CHs ismuch higher than the other protocols which also dem-onstrated that the proposed protocol has a better networkthroughout
6 Conclusions
According to the characteristics of field observation in-strument networking an improved protocol FOI-LEACHbased on LEACH protocol was proposed in this paper Byconsidering the energy factor in the CH election threshold
and referring to the SEP protocol to set up two kinds ofnodes with different initial energies which are calledadvanced nodes and normal nodes the network model offield observation instruments has been established Inaddition to solve the problem that the LEACH protocolconsumes much energy during transmission and results inuneven energy consumption for the direct and long-distance transmission the improved protocol adopted the3 zones of partitioning mechanism and the multihoptransmission mechanism to alleviate and avoid the ldquohotspotrdquo problems Furthermore energy supplies were addedto the nodes in A and B zones that are responsible formore energy transmission so as to balance the energyconsumption of the network and prolong the networklifetime In the simulation experiments we compared theperformance of the FOI-LEACH protocol with theLEACH SEP and PECRP protocols in two cases with orwithout energy supply Comparing performance indica-tors of network lifetime energy consumption rate sta-bility and network throughput the proposed FOI-LEACH protocol can slow down the death of nodes andthe energy consumption rate obviously and shows asignificantly better performance than other three proto-cols e experimental results demonstrated that the FOI-LEACH protocol could balance network energy con-sumption and alleviate the ldquohot spotrdquo problem to extendthe lifetime of network nodes in the field observationinstruments network e future work is to implementand port the improved protocol to the hardware of net-working node we designed and developed previously andtest and verify the feasibility and stability of the protocolin the actual situation
Data Availability
e initial nodes are generated randomly in the networkand there are no observation data used in the simulationexperiments
0
20000
40000
60000
80000
100000
120000
140000
Pack
ets t
o CH
200
400
600
800
2200
1200
1800
2000
1400
1600
23000
1000
Number of rounds
LEACHSEP
PECRPImproved protocol
Figure 18 Comparison of packets sent to CHs from nodes with power supply
Journal of Electrical and Computer Engineering 17
Conflicts of Interest
e authors declare that there are no conflicts of interest
Acknowledgments
is work was supported by the National Nature ScienceFoundation of China (Grant no 61862038) the LanzhouTalent Innovation and Entrepreneurship Technology PlanProject (no 2019-RC-14) and the Foundation of a HundredYouth Talents Training Program of Lanzhou JiaotongUniversity
References
[1] J Y Huo Z N Ren and Y R Yang A Kind of InstrumentNetwork Node Equipment and Monitoring System ChinesePatents Beijing China 2017
[2] J Y Huo Key Technology and Application Research ofE-Science Virtual Joint Observation System for Geoscience inCold and Dry Regions University of Chinese Academy ofSciences Beijing China 2012
[3] I F Akyildiz W L Weilian Su Y Sankarasubramaniam andE Cayirci ldquoA survey on sensor networksrdquo IEEE Communi-cations Magazine vol 40 no 8 pp 102ndash114 2002
[4] W R Heinzelman A Chandrakasan and H BalakrishnanldquoEnergy-efficient communication protocol for wirelessmicrosensor networksrdquo in Proceedings of the 33rd HawaiiIntentional Conference on System Sciences Maui HI USAJanuary 2000
[5] D Mehta and S Saxena ldquoA comparative analysis of energyefficient hierarchical routing protocols for wireless sensornetworksrdquo in Proceedings of the 2018 4th InternationalConference on Computing Sciences (ICCS) pp 53ndash58Jalandhar India August 2018
[6] C Karlof and D Wagner ldquoSecure routing in wireless sensornetworks attacks and countermeasuresrdquo Ad Hoc Networksvol 1 2003
[7] L B Oliveira A Ferreira M A Vilaca et al ldquoSecLEACH-onthe security of clustered sensor networksrdquo Signal Processingvol 87 2007
[8] Y Y Gu GW Bai and J J Tao ldquoAZM-LEACH autonomouszone-based multi-hop routing protocol in WSNsrdquo ComputerEngineering and Applications vol 47 no 20 pp 58ndash61 2011
[9] L XWang Research on Routing Technology ofWireless SensorNetworks Based on Data Aggregation Shenyang LigongUniversity Shenyang China 2015
[10] J P Shao Research on Key Energy-Efficient Routing Tech-nology of WSN Based on Cluster Shenyang Ligong UniversityShenyang China 2015
[11] V K Arora V Sharma and M Sachdeva ldquoA survey onLEACH and otherrsquos routing protocols in wireless sensornetworkrdquo Optik vol 127 no 16 pp 6590ndash6600 2016
[12] W B Heinzelman A P Chandrakasan and H BalakrishnanldquoAn application-specific protocol architecture for wirelessmicrosensor networksrdquo IEEE Transactions on WirelessCommunications vol 1 no 4 pp 660ndash670 2002
[13] S Al-Sodairi and R Ouni ldquoReliable and energy-efficientmulti-hop LEACH-based clustering protocol for wirelesssensor networksrdquo Sustainable Computing Informatics andSystems vol 20 pp 1ndash13 2018
[14] O Younis and S Fahmy ldquoHEED a hybrid energy-efficientdistributed clustering approach for ad hoc sensor networksrdquo
IEEE Transactions on Mobile Computing vol 3 no 4pp 366ndash379 2004
[15] B B Chen and Y L Shi ldquoWSN routing protocol based oncluster heads selection in regionsrdquo Computer Engineeringvol 37 no 19 pp 96ndash98 2011
[16] P Azada ldquoCluster head selection in wireless sensor networksunder fuzzy environmentrdquo ISRN Sensor Networks vol 2013Article ID 909086 8 pages 2013
[17] S Soro and W B Heinzelman ldquoCluster head election tech-niques for coverage preservation in wireless sensor networksrdquoAd Hoc Networks vol 7 no 5 pp 955ndash972 2009
[18] A akkar ldquoDEAL distance and energy based advancedleach protocolrdquo in Proceedings of the International Conferenceon Information and Communication Technology for IntelligentSystems pp 370ndash376 Ahmedabad India March 2017
[19] T Y Chang W N Liu Y Zhang and H Y Li ldquoOptimizedLEACH protocol based on distance and energy of clusterheadrdquo Journal of Hebei University (Natural Science Edition)vol 39 no 2 pp 194ndash200 2019
[20] P Mehra M Doja and B Alam ldquoStability enhancement inLEACH (SE-LEACH) for homogeneousWSNrdquo EAI EndorsedTransactions on Scalable Information Systems vol 6 no 20pp 1ndash9 2019
[21] G Smaragdakis I Matta and A Bestavros ldquoSEP a stableelection protocol for clustered heterogeneous wireless sensornetworksrdquo in Proceedings of the Second InternationalWorkshop on Sensor and Actor Network Protocols and Ap-plications (SANPA 2004) pp 1ndash11 Boston MA USA June2004
[22] F S Hu and Q Xiao ldquoMulti-hop routing algorithm of energy-balancing based on LEACHrdquo Journal of Chinese ComputerSystems vol 35 no 1 pp 72ndash75 2014
[23] C F Li M Ye G H Chen and J Wu ldquoAn energy-efficientunequal clustering mechanism for wireless sensor networksrdquoin Proceedings of the IEEE International Conference on MobileAdhoc and Sensor Systems Conference p 604 WashingtonDC USA November 2005
[24] E Alnawafa I Marghescu and MHT ldquoMulti-hop techniquefor the improvement of leach protocolrdquo in Proceedings of the2016 15th RoEduNet Conference Networking in Education andResearch pp 1ndash5 Bucharest Romania September 2016
[25] E Alnawafa and I Marghescu ldquoIMHT improved MHT-LEACH protocol for wireless sensor networksrdquo in Proceedingsof the 2017 8th International Conference on Information andCommunication Systems (ICICS) pp 246ndash251 Irbid JordanApril 2017
[26] J Y Huo Z Zhang and C Tao ldquoUsing IPv6 address ad-vantage to build Network Node of Field observation In-struments in cold and arid areasrdquo China Education Networkno 5 pp 45-46 2018
[27] L Mateu and F Moll ldquoReview of energy harvesting tech-niques and applications for microelectronicsrdquo in Proceedingsof the International Society for Optical Engineering pp 359ndash373 Bellingham WA USA October 2005
[28] G Wang and R Y Wang ldquoRouting algorithm based oncluster-head optimization for self-energized wireless sensornetworkrdquo Journal of Computer Applications vol 38 no 334pp 201ndash216 2018
[29] X P Fan X Yang S Q Liu and Z H Qu ldquoClusteringrouting algorithm for wireless sensor networks with powerharvestingrdquo Computer Engineering vol 39 no 11 pp 126ndash134 2008
18 Journal of Electrical and Computer Engineering
[30] C H Zhang ldquoStudy on the energy heterogeneous clusteringrouting protocol for wireless sensor networksrdquo Science ampTechnology Vision no 13 pp 71+164ndash165 2012
[31] T Liu and F Li ldquoPower-efficient clustering routing protocolbased on applications in wireless sensor networkrdquo in Pro-ceedings of the International Conference on Wireless Com-munications IEEE Press Melbourne Australia September2009
Journal of Electrical and Computer Engineering 19
Conflicts of Interest
e authors declare that there are no conflicts of interest
Acknowledgments
is work was supported by the National Nature ScienceFoundation of China (Grant no 61862038) the LanzhouTalent Innovation and Entrepreneurship Technology PlanProject (no 2019-RC-14) and the Foundation of a HundredYouth Talents Training Program of Lanzhou JiaotongUniversity
References
[1] J Y Huo Z N Ren and Y R Yang A Kind of InstrumentNetwork Node Equipment and Monitoring System ChinesePatents Beijing China 2017
[2] J Y Huo Key Technology and Application Research ofE-Science Virtual Joint Observation System for Geoscience inCold and Dry Regions University of Chinese Academy ofSciences Beijing China 2012
[3] I F Akyildiz W L Weilian Su Y Sankarasubramaniam andE Cayirci ldquoA survey on sensor networksrdquo IEEE Communi-cations Magazine vol 40 no 8 pp 102ndash114 2002
[4] W R Heinzelman A Chandrakasan and H BalakrishnanldquoEnergy-efficient communication protocol for wirelessmicrosensor networksrdquo in Proceedings of the 33rd HawaiiIntentional Conference on System Sciences Maui HI USAJanuary 2000
[5] D Mehta and S Saxena ldquoA comparative analysis of energyefficient hierarchical routing protocols for wireless sensornetworksrdquo in Proceedings of the 2018 4th InternationalConference on Computing Sciences (ICCS) pp 53ndash58Jalandhar India August 2018
[6] C Karlof and D Wagner ldquoSecure routing in wireless sensornetworks attacks and countermeasuresrdquo Ad Hoc Networksvol 1 2003
[7] L B Oliveira A Ferreira M A Vilaca et al ldquoSecLEACH-onthe security of clustered sensor networksrdquo Signal Processingvol 87 2007
[8] Y Y Gu GW Bai and J J Tao ldquoAZM-LEACH autonomouszone-based multi-hop routing protocol in WSNsrdquo ComputerEngineering and Applications vol 47 no 20 pp 58ndash61 2011
[9] L XWang Research on Routing Technology ofWireless SensorNetworks Based on Data Aggregation Shenyang LigongUniversity Shenyang China 2015
[10] J P Shao Research on Key Energy-Efficient Routing Tech-nology of WSN Based on Cluster Shenyang Ligong UniversityShenyang China 2015
[11] V K Arora V Sharma and M Sachdeva ldquoA survey onLEACH and otherrsquos routing protocols in wireless sensornetworkrdquo Optik vol 127 no 16 pp 6590ndash6600 2016
[12] W B Heinzelman A P Chandrakasan and H BalakrishnanldquoAn application-specific protocol architecture for wirelessmicrosensor networksrdquo IEEE Transactions on WirelessCommunications vol 1 no 4 pp 660ndash670 2002
[13] S Al-Sodairi and R Ouni ldquoReliable and energy-efficientmulti-hop LEACH-based clustering protocol for wirelesssensor networksrdquo Sustainable Computing Informatics andSystems vol 20 pp 1ndash13 2018
[14] O Younis and S Fahmy ldquoHEED a hybrid energy-efficientdistributed clustering approach for ad hoc sensor networksrdquo
IEEE Transactions on Mobile Computing vol 3 no 4pp 366ndash379 2004
[15] B B Chen and Y L Shi ldquoWSN routing protocol based oncluster heads selection in regionsrdquo Computer Engineeringvol 37 no 19 pp 96ndash98 2011
[16] P Azada ldquoCluster head selection in wireless sensor networksunder fuzzy environmentrdquo ISRN Sensor Networks vol 2013Article ID 909086 8 pages 2013
[17] S Soro and W B Heinzelman ldquoCluster head election tech-niques for coverage preservation in wireless sensor networksrdquoAd Hoc Networks vol 7 no 5 pp 955ndash972 2009
[18] A akkar ldquoDEAL distance and energy based advancedleach protocolrdquo in Proceedings of the International Conferenceon Information and Communication Technology for IntelligentSystems pp 370ndash376 Ahmedabad India March 2017
[19] T Y Chang W N Liu Y Zhang and H Y Li ldquoOptimizedLEACH protocol based on distance and energy of clusterheadrdquo Journal of Hebei University (Natural Science Edition)vol 39 no 2 pp 194ndash200 2019
[20] P Mehra M Doja and B Alam ldquoStability enhancement inLEACH (SE-LEACH) for homogeneousWSNrdquo EAI EndorsedTransactions on Scalable Information Systems vol 6 no 20pp 1ndash9 2019
[21] G Smaragdakis I Matta and A Bestavros ldquoSEP a stableelection protocol for clustered heterogeneous wireless sensornetworksrdquo in Proceedings of the Second InternationalWorkshop on Sensor and Actor Network Protocols and Ap-plications (SANPA 2004) pp 1ndash11 Boston MA USA June2004
[22] F S Hu and Q Xiao ldquoMulti-hop routing algorithm of energy-balancing based on LEACHrdquo Journal of Chinese ComputerSystems vol 35 no 1 pp 72ndash75 2014
[23] C F Li M Ye G H Chen and J Wu ldquoAn energy-efficientunequal clustering mechanism for wireless sensor networksrdquoin Proceedings of the IEEE International Conference on MobileAdhoc and Sensor Systems Conference p 604 WashingtonDC USA November 2005
[24] E Alnawafa I Marghescu and MHT ldquoMulti-hop techniquefor the improvement of leach protocolrdquo in Proceedings of the2016 15th RoEduNet Conference Networking in Education andResearch pp 1ndash5 Bucharest Romania September 2016
[25] E Alnawafa and I Marghescu ldquoIMHT improved MHT-LEACH protocol for wireless sensor networksrdquo in Proceedingsof the 2017 8th International Conference on Information andCommunication Systems (ICICS) pp 246ndash251 Irbid JordanApril 2017
[26] J Y Huo Z Zhang and C Tao ldquoUsing IPv6 address ad-vantage to build Network Node of Field observation In-struments in cold and arid areasrdquo China Education Networkno 5 pp 45-46 2018
[27] L Mateu and F Moll ldquoReview of energy harvesting tech-niques and applications for microelectronicsrdquo in Proceedingsof the International Society for Optical Engineering pp 359ndash373 Bellingham WA USA October 2005
[28] G Wang and R Y Wang ldquoRouting algorithm based oncluster-head optimization for self-energized wireless sensornetworkrdquo Journal of Computer Applications vol 38 no 334pp 201ndash216 2018
[29] X P Fan X Yang S Q Liu and Z H Qu ldquoClusteringrouting algorithm for wireless sensor networks with powerharvestingrdquo Computer Engineering vol 39 no 11 pp 126ndash134 2008
18 Journal of Electrical and Computer Engineering
[30] C H Zhang ldquoStudy on the energy heterogeneous clusteringrouting protocol for wireless sensor networksrdquo Science ampTechnology Vision no 13 pp 71+164ndash165 2012
[31] T Liu and F Li ldquoPower-efficient clustering routing protocolbased on applications in wireless sensor networkrdquo in Pro-ceedings of the International Conference on Wireless Com-munications IEEE Press Melbourne Australia September2009
Journal of Electrical and Computer Engineering 19
[30] C H Zhang ldquoStudy on the energy heterogeneous clusteringrouting protocol for wireless sensor networksrdquo Science ampTechnology Vision no 13 pp 71+164ndash165 2012
[31] T Liu and F Li ldquoPower-efficient clustering routing protocolbased on applications in wireless sensor networkrdquo in Pro-ceedings of the International Conference on Wireless Com-munications IEEE Press Melbourne Australia September2009
Journal of Electrical and Computer Engineering 19