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E1 E1-E2 CM E2 CM RF Planning and Drive Test RF Planning and Drive Test for BSNL internal circulation only RF Planning and Drive Test RF Planning and Drive Test for BSNL internal circulation only

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Microsoft PowerPoint - 03.RF Planning and Drive Test.ppt [Compatibility Mode]RF Planning and Drive Test RF Planning and Drive Test
for BSNL internal circulation only
RF Planning and Drive Test RF Planning and Drive Test
for BSNL internal circulation only
A cell can be defined
as the area covered
Main Elements of Radio
– Capacity requirements
for BSNL internal circulation only
• Quality of service for the air interface, in terms GoS
– Coverage requirements
• Determine number of cells required for capacity
by using Erlang formula.
by using Erlang formula.
by using propagation model.
uses one traffic channel for one hour.
for BSNL internal circulation only
ERLANG TABLES
– Erlang B
– Erlang C
for BSNL internal circulation only
then they get dropped (i.e. no queuing possible).
• Erlang C considers that if a call does not get
through then it will wait in a queue.
ERLANG TABLES
generated by X No. of TRXs for different Grades
of Service.
POSSIBLE CHANNEL COMBINATIONS
TCH TCHTCH
CM
TCH TCH TCH TCH TCH TCH TCH TCH
TCH TCH TCH TCH TCH TCH TCH
FREQUENCY RE-USE
– the average number of the transceivers
– the total number of frequencies.
for BSNL internal circulation only
FREQUENCY RE-USE FACTOR
• If there are 3 TRX that are used per base station
and the total number of frequencies available is
27.The total number of frequencies available for
for BSNL internal circulation only
re-use is 27/3 = 9
loss.
loss.
caution .
models with terrain data.
– Walfisch-ikegami model
• Pre planning
• Site survey
• Frequency allocation
• Frequency allocation
• Parameter planning
parameters like power budget calculations and
considering path loss calculations.
improving the performance of the radio network.
for BSNL internal circulation only
WHAT IS OPTIMIZATION
OPTIMISATION
transmission antennas.
for BSNL internal circulation only
DIVERSITY
the reception power of the receiving antenna.
• Major diversity techniques are
– frequency diversity
– polarization diversity
RADIO NETWORK PLANNING
o Application of suitable propagation model
for BSNL internal circulation only
o Application of suitable propagation model
o Methods to improve signal received by MS
o Study of RRM ( Radio resource management)
o Study of KPI’s( Key performance parameters)
MS BTS MSCBSC
LAPD m
MTP
functions related to
– mobile location updation
LINK PROTOCOLS
information flow (traffic and signalling) takes
place via three protocols, known as link
for BSNL internal circulation only
protocols .
• LAPD over the BTS-BSC connection.
• MTP is used for signalling transport over the
for BSNL internal circulation only
SS7 network.
operational, its performance is monitored.
• The performance is compared against chosen
key performance indicators (KPIs).
• After fine-tuning, the results are then applied to
the network to get the desired performance.
STUDY OF KPIs
• KPls can be subdivided according to the areas of functioning, such as – area level
– cell level
– TRX level.
• Area-level KPls can include – SDCCH requests
– dropped SDCCH total
– outgoing BSC control HO attempts
– intra-cell HO attempts, etc.
• Selection of the drive testing path.
• To have the appropriate kits including
for BSNL internal circulation only
– Mobile equipment (usually three mobiles)
– Drive testing software (on a laptop)
– A GPS (global positioning system) unit.
USB2 USB1
1. Scanner
for BSNL internal circulation only
Com 1
gap of few seconds (usually 15-20 s).
• The third mobile is usually used for testing the
for BSNL internal circulation only
coverage.
drops it will attempt another call.
DRIVE TEST PROCESS
speed and in a reasonable time.
• If there are lots of dropped calls, the problem is
for BSNL internal circulation only
analysed to find a solution for it and to propose
changes.
• Antenna orientation adjustment
finalisation of Radio network planning.
DRIVE TEST TOOL
– Optimizing
– Troubleshooting
costs.
diagnosing and benchmarking in order to make
best use of available resources.
for BSNL internal circulation only
• They also enable engineers to troubleshoot
problems quickly.
for mobile radio network planning.
• It is a
– highly graphical
TEMS CELLPLANNER UNIVERSAL
• It assists the user in a number of complex tasks,
including
– traffic planning
– site configuration
– frequency planning.
– iDEN
– CDMA,CDMA2000 1xRTT
for BSNL internal circulation only