GSM Principles Com 4

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Generation Roadmap forGeneration Roadmap forCellular TelephonyCellular Telephony

Prepared by:Prepared by:MIHIR KUMBHAKARMIHIR KUMBHAKAR

AGM(CMTS)AGM(CMTS)Dated:10.03.07


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Wireless technology is accelerating veryWireless technology is accelerating veryfast.fast.

It is quickly moving into 1G,2G,2.5G,3G ,It is quickly moving into 1G,2G,2.5G,3G ,4G and NGN4G and NGN


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11 stst GenerationGeneration

The first generation of mobile cellular The first generation of mobile cellular telecommunications systems appeared in thetelecommunications systems appeared in the

1980s.1980s.The first generation used analog transmissionThe first generation used analog transmissiontechniques for traffic, which was almost entirelytechniques for traffic, which was almost entirelyvoice.voice.There was no dominant standard but severalThere was no dominant standard but severalcompeting ones.competing ones.


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Such asSuch as Nordic Mobile TelephoneNordic Mobile Telephone (NMT)(NMT) used in used inScandinavia,southern EuropeScandinavia,southern Europe etcetc

It comes in two variations:It comes in two variations:oo NMT-450NMT-450

oo NMT-900NMT-900 Total Access Communications SystemTotal Access Communications System (TACS)(TACS) used usedin UK,and middle Eastern countries.It uses 900MHz band.in UK,and middle Eastern countries.It uses 900MHz band. Advanced Mobile Phone ServiceAdvanced Mobile Phone Service (AMPS(AMPS )).- used in.- used in

US,Australia,New Zealand.It uses 800MHz bandUS,Australia,New Zealand.It uses 800MHz band


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22 ndnd GenerationGeneration It has been introduced from the year 1992.It has been introduced from the year 1992.It uses digital radio transmis-sion for traffic.It uses digital radio transmis-sion for traffic.The 2G networks have much higher capacity than theThe 2G networks have much higher capacity than the

first-generation systems.first-generation systems.

GSM is by far the most successful and widely used 2GGSM is by far the most successful and widely used 2Gsystem.system.Data rate supported : 9.6kbps to 14.4 kbpsData rate supported : 9.6kbps to 14.4 kbpsIt uses Circuit switchingIt uses Circuit switching


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There are several standards for 2G systems.such as-There are several standards for 2G systems.such as-

##Global System for MobileGlobal System for Mobile (GSM) communications(GSM) communications -Designed and developed by a-Designed and developed by a

number of different organization working together.number of different organization working together.## code-division multiple accesscode-division multiple access (CDMA) IS-95(CDMA) IS-95 -Designed and developed by a single-Designed and developed by a single

company,Qualcomm.company,Qualcomm.

v CDMA uses different codes to separate transmissions on the samev CDMA uses different codes to separate transmissions on the samefrequency.frequency.

v IS-95 is the only 2G CDMA standard so far to be operatedv IS-95 is the only 2G CDMA standard so far to be operatedcommercially.commercially.v It is used in the United States, South Korea, Hong Kong, Japan,v It is used in the United States, South Korea, Hong Kong, Japan,Singapore etc.Singapore etc.


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Generation 2.5Generation 2.5It has been introduced in the year 2000-2001It has been introduced in the year 2000-2001

Generation 2.5 is a designation that broadly includes all advanced upgrades for the 2G networksGeneration 2.5 is a designation that broadly includes all advanced upgrades for the 2G networks

2.5G GSM system includes2.5G GSM system includes General Packet Radio ServicesGeneral Packet Radio Services (GPRS), and(GPRS), and Enhanced Data Rates for Enhanced Data Rates for Global EvolutionGlobal Evolution (EDGE) in addition to the 2G systems(EDGE) in addition to the 2G systems ..

Data rate supported: depending on the coding scheme(CS) and the no. of time slots used( 1 up to 8)Data rate supported: depending on the coding scheme(CS) and the no. of time slots used( 1 up to 8)

It uses circuit switching and packet switching bothIt uses circuit switching and packet switching both

It supports the data rate up to 384 kbpsIt supports the data rate up to 384 kbps


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33 rd rd GenerationGeneration It has been introduced in the year 2001 as trial versionIt has been introduced in the year 2001 as trial version

It supports the data rate up to 2 mbpsIt supports the data rate up to 2 mbps

Evolution of GSM and CDMA has taken them as W-Evolution of GSM and CDMA has taken them as W-CDMA(UMTS) and CDMA-2000 in third generation.CDMA(UMTS) and CDMA-2000 in third generation.

It supports both circuit switching and packet switchingIt supports both circuit switching and packet switching


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44 thth generation and NGNgeneration and NGN This technology is expected to arrive not before the year 2010 .

It will support the data rate up to 100 mbps.

Multimedia, mobile TV,mobile broadband wireless access etcwill be possible because of its high band width.

It will support both circuit switching and packet switching


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GSM OverviewGSM Overview>GSM stands for Global System for Mobile communication >GSM Technology is one of the different types of the wireless

communication available in the world.

Frequency range-*Uplink Frequency: 890 Mhz 915Mhz*Downlink Frequency: 935Mhz- 960Mhz.

Modulation Technique- GMSK


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Speech is divided into 20 msec sample.Each20ms sample is encoded using 260 bits.(Thatrequires 13 kbps.)

Band width:each radio channel in the GSM systemhas a frequency bandwidth of 200khz.

Number of Channels:124 radio channel.


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GSM NetworkGSM Network


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BSSBSSBSSBSS - Controls radio link with mobile station.- Controls radio link with mobile station.

It consists of It consists of BTSBTS (Base transreceiver Station)-It defines a cell(Base transreceiver Station)-It defines a cell

and is responsible to establish the radio linkand is responsible to establish the radio linkcontrol protocol with MS.control protocol with MS.

BSCBSC (Base Station Controller)-Controls multiple(Base Station Controller)-Controls multipleBTSs and manages radio channel set up andBTSs and manages radio channel set up and

handovers.BSC is the connection between BTShandovers.BSC is the connection between BTSand the MSCs.and the MSCs.


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NSSNSSNetwork & Switching Subsystem(NSS)Network & Switching Subsystem(NSS) -Mobility-Mobilitymanagement and Switching of calls between mobilemanagement and Switching of calls between mobileusers and between mobile and fixed network users.users and between mobile and fixed network users.

It consists of :It consists of : MSCMSC - is the central component of the NSS.- is the central component of the NSS.Operates all switching functions for mobilesOperates all switching functions for mobiles

within its jurisdiction.Interfaces with mobile andwithin its jurisdiction.Interfaces with mobile andother (Including fixed) networks.other (Including fixed) networks.

Manages the location of mobileManages the location of mobile


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ContinuedContinued

Switches callsSwitches callsManages security features.Manages security features.

Controls hand over between BSCsControls hand over between BSCsResources managementResources managementInterworks with and manages networkInterworks with and manages networkdatabase.database.

Collect call billing data and sends to BillingCollect call billing data and sends to Billingcenter.center.Collects traffic statistics for performanceCollects traffic statistics for performancemonitoring.monitoring.


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Continued..Continued..HLRHLR -Contains all subscriber information for the-Contains all subscriber information for the

purposes of call control and location determination.purposes of call control and location determination.

VLRVLR - is only a temporary storage while the particular- is only a temporary storage while the particularsubscriber is located in the geographical areasubscriber is located in the geographical areacontrolled by the MSC/VLR.controlled by the MSC/VLR.

AUCAUC - Is a protected database that stores the security- Is a protected database that stores the securityinformation for each subscriber.(A copy of the secretinformation for each subscriber.(A copy of the secretkey is stored in the SIM)key is stored in the SIM)


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ContinuedContinued

EIREIR -It contains three list of IMEI-It contains three list of IMEInumber.number.

White listWhite list .-Valid mobile equipment in.-Valid mobile equipment in

thethe networknetwork Grey listGrey list .- Suspected numbers.- Suspected numbers Black listBlack list -Totally barred.-Totally barred.


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Logical ChannelsLogical ChannelsFive types of logical channels:Five types of logical channels:1.Traffic Channels1.Traffic Channels** TCHTCH - Used to carry traffic.- Used to carry traffic.

2.Broadcast channels.2.Broadcast channels.*BCCH-*BCCH- used to carry signaling and control infoused to carry signaling and control info* FCCH-* FCCH- used to correct the frequency of Mobileused to correct the frequency of Mobile* SCH-* SCH- used for synchronization of the base stationused for synchronization of the base station

3.common control channels3.common control channels*PCH-*PCH- used to page the mobileused to page the mobile*AGCH-*AGCH- used to access the signaling channelused to access the signaling channel

*RACH-*RACH- used by MS to request for signaling channelused by MS to request for signaling channel4.Dedicated Control Channels4.Dedicated Control Channels*SDCCH-*SDCCH- used as signaling channelused as signaling channel*SACCH-*SACCH- used to carry measurement reportsused to carry measurement reports*FACCH-*FACCH- used during handoverused during handover

5.CellBroad cast channel5.CellBroad cast channel*CBCH-*CBCH- used to broadcast short messages in cellsused to broadcast short messages in cells


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MSISDNMSISDNThe only important number for a user of GSM is theThe only important number for a user of GSM is thephone number i.e.MSISDN.phone number i.e.MSISDN.

The MSISDN follows the ITU-T standard E.164 forThe MSISDN follows the ITU-T standard E.164 foraddresses as it is also used in fixed ISDN networks.addresses as it is also used in fixed ISDN networks.

This number consists of theThis number consists of the country code(cc)country code(cc) ( 91 for( 91 forIndia),the national destination codeIndia),the national destination code (NDC)(NDC) (the address(the addressof the network provider ; e.,g., 9434 for BSNL WB) andof the network provider ; e.,g., 9434 for BSNL WB) andthe subscriber numberthe subscriber number (SN)(SN) ..


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IMSIIMSIGSM uses the IMSI for internal unique identification of aGSM uses the IMSI for internal unique identification of asubscriber.subscriber.

The IMSI follows the ITU-T standard E.212 NumberThe IMSI follows the ITU-T standard E.212 Numberseries.series.

IMSI consists of mobile country codeIMSI consists of mobile country code (MCC)(MCC) (e.g.,404 for(e.g.,404 forIndia),the mobile network codeIndia),the mobile network code (MNC)(MNC) (i.e.,code of the(i.e.,code of theHLR; e.g.,74 of BSNL WB),and finally the mobileHLR; e.g.,74 of BSNL WB),and finally the mobilesubscriber identification numbersubscriber identification number (MSIN).(MSIN).


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Location Updating (LU)Location Updating (LU)When the LU request is received by the new VLR,authenticationWhen the LU request is received by the new VLR,authenticationis performed.is performed.

If authentication is successful,the VLR checks its database toIf authentication is successful,the VLR checks its database todetermine whether it has a record for this MS-subscription.determine whether it has a record for this MS-subscription.

When VLR finds no record for the MS,it sends a request to theWhen VLR finds no record for the MS,it sends a request to thesubscribers HLR for a copy of the MS-subscription.subscribers HLR for a copy of the MS-subscription.

The HLR passes the information to the VLR and updates itsThe HLR passes the information to the VLR and updates itslocation information for the subs.The HLR instructs the old VLR tolocation information for the subs.The HLR instructs the old VLR to

delete the information it has about the MS- subscription.delete the information it has about the MS- subscription.


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Inbound Roamer registrationInbound Roamer registration- Location Update-Diagram- Location Update-Diagram

1. UpLoc

1. UpLoc1. UpLoc

WB BSNL

NLDHLR

UK Subscriber

GMSC

VMSC/VLR

3. ISD_resp

UK

HLRGMSC

SCCPCdPA: 44-181-123456(MGT derived fromIMSIS analysis)CgPA: 919434099995(VLR)

MAPIMSI: 234-15-123456MSC/VLR: 919434099995

SCCPCdPA: 44-181-HLRUK

CgPA: 919434099995(VLR1 )

3. ISD_resp

2. ISD

4. UPL_resp

SCCPCdPA: 919434099995(VLR) CgPA: 44-181-HLRofUK1

MAPIMSI: 234-15-123456MSISDN: 44-181-654321

2.ISD

2.ISD

4. UPL_resp


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Call from an MS(MO Calls)Call from an MS(MO Calls)The MS uses RACH to ask for a signaling channel.The MS uses RACH to ask for a signaling channel.

The BSC/TRC allocates a signaling channel,using AGCH.The BSC/TRC allocates a signaling channel,using AGCH.

The MS sends a call set-up request via SDCCH to theThe MS sends a call set-up request via SDCCH to theMSC/VLR.Over SDCCH all signaling preceding a callMSC/VLR.Over SDCCH all signaling preceding a calltakes place (e.g.,authentication, ciphering,sending B-takes place (e.g.,authentication, ciphering,sending B-subscribers number,checking of o/g barring parametersubscribers number,checking of o/g barring parameteretc.).etc.).


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MO CALL Continued..MO CALL Continued..The MSC/VLR instructs the BSC/TRC to allocate anThe MSC/VLR instructs the BSC/TRC to allocate anidle TCH.The RBS and MS are told to tune to theidle TCH.The RBS and MS are told to tune to theTCH.TCH.

The MSC/VLR forwards the B-number to anThe MSC/VLR forwards the B-number to anexchange in the PSTN,which establishes aexchange in the PSTN,which establishes aconnection to the subscriber.connection to the subscriber.

If the B-subscriber answers,the connection isIf the B-subscriber answers,the connection isestablished.established.


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Call to an MS (MT Calls)Call to an MS (MT Calls)The PSTN subscriber dials in the MSs telephone numberThe PSTN subscriber dials in the MSs telephone number(MSISDN).The MSISDN is analyzed in the PSTN,which(MSISDN).The MSISDN is analyzed in the PSTN,whichidentifies that this is a call to a mobile network subscriber.Aidentifies that this is a call to a mobile network subscriber.Aconnection is established to the MSs home GMSC.connection is established to the MSs home GMSC.

The GMSC analyzes the MSISDN to find out which HLR theThe GMSC analyzes the MSISDN to find out which HLR the

MS is registered in,and queries the HLR for informationMS is registered in,and queries the HLR for informationabout how to route the call to the serving MSC/VLR.about how to route the call to the serving MSC/VLR.

The HLR translates MSISDN into IMSI,and determines whichThe HLR translates MSISDN into IMSI,and determines whichMSC/VLR is currentlyMSC/VLR is currently serving the MS.serving the MS.


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MT Calls continued..MT Calls continued..The HLR requests an MSRN from the servingThe HLR requests an MSRN from the servingMSC/VLR.The MSC/VLR returns an MSRN via HLR to theMSC/VLR.The MSC/VLR returns an MSRN via HLR to theGMSC.GMSC.

The GMSC analyses the MSRN and routes the call to theThe GMSC analyses the MSRN and routes the call to theMSC/VLR.MSC/VLR.

The MSC/VLR knows which LA the MS is located in.AThe MSC/VLR knows which LA the MS is located in.Apaging message is sent to the BSCs controlling the LA.paging message is sent to the BSCs controlling the LA.

The BSCs distribute the paging message to the RBSsThe BSCs distribute the paging message to the RBSsin the desired LA.in the desired LA.

ll dMT C ll i d


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MT Calls continued..MT Calls continued..The RBSs transmit the message over the air interface using PCH withThe RBSs transmit the message over the air interface using PCH withIMSI/TMSI.IMSI/TMSI.

When the MS detects the paging message,it sends a requests on RACH for aWhen the MS detects the paging message,it sends a requests on RACH for aSDCCH.SDCCH.

The BSC provides a SDCCH,using AGCH.The BSC provides a SDCCH,using AGCH.

SDCCH is used for the call set-up procedures.Over the SDCCH all signalingSDCCH is used for the call set-up procedures.Over the SDCCH all signaling

preceding takes place.preceding takes place.

The MSC/VLR instructs the BSC/TRC to allocate an idle TCH.The RBS and MSThe MSC/VLR instructs the BSC/TRC to allocate an idle TCH.The RBS and MSare told to tune to the TCH.The mobile phone rings.If subscriber answers,theare told to tune to the TCH.The mobile phone rings.If subscriber answers,theconnection is established.connection is established.


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Call to an MS(MT Calls) inCall to an MS(MT Calls) inRoaming-DiagramRoaming-Diagram

WB BSNL

NLDHLR

UK Subscriber

GMSC

VMSC/VLR

UK

HLR

GMSC

44-181-123456

PSTN

DIALS

IAM

1.SRI2.PRN

2.PRN2.PRN

MSISDN

IMSI

2.PRN3.PRNACK

3.PRNACK

3.PRNACK

3.PRNACK

MSRN MSRN

4.SRIACK

MSRN

5.ISUPIAM

5.ISUPIAM

5.ISUPIAM

6.PAGING

6.ACM

6.ACM

6.ACM

7.ANM

7.ANM

7.ANM

8.Disconnect

8.REL

8.REL

9.RELACK

9.RELACK

9.RELACK


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MO SMS -DiagramMO SMS -DiagramWB BSNL

NLDHLR

UK Subscriber

GMSC

VMSC/VLR

UK

HLRGMSC

SCCPCdPA: 44-181-123456(MGT derived fromIMSIS analysis)CgPA: 919434099995(VLR)

MAPIMSI: 234-15-123456

SCCPCdPA: 919434099995(VLR) CgPA: 44-181-HLRofUK1

MO -FSM MO -FSM

SMSC

MO-FSM-RSP MO -FSM

MO-FSM-RSPMO-FSM-RSP

An MS establishes a connection to the network,An MS establishes a connection to the network,

as in the normal call set-up.as in the normal call set-up.The MS sends the short message using SDCCH toThe MS sends the short message using SDCCH to

SMSC via MSC/VLR.The SMSC in turn forwards theSMSC via MSC/VLR.The SMSC in turn forwards themessage to its destination.message to its destination.


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MT SMSMT SMSA user sends a message to a SMSC.A user sends a message to a SMSC.

The SMSC sends the message to the SMS-GMSC.The SMSC sends the message to the SMS-GMSC.

The SMS-GMSC queries the HLR for routing information.The SMS-GMSC queries the HLR for routing information.

The HLR returns routing information to the SMS-GMSC.The HLR returns routing information to the SMS-GMSC.

The SMS-GMSC reroutes the message to the MSC/VLR.The SMS-GMSC reroutes the message to the MSC/VLR.

The MS is paged and a connection is set up between the MSThe MS is paged and a connection is set up between the MSand the network,as in the normal call set-up case.and the network,as in the normal call set-up case.


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MT SMS ContinuedMT SMS ContinuedThe MSC/VLR delivers the message to the MS.ShortThe MSC/VLR delivers the message to the MS.Shortmessages are transmitted on SDCCH.messages are transmitted on SDCCH.

If the delivery was successful,a report is sent from theIf the delivery was successful,a report is sent from theMSC/VLR to the SMSC,if not,the HLR is informed by theMSC/VLR to the SMSC,if not,the HLR is informed by the

MSC/VLR, and a failure report is sent to SMSC.MSC/VLR, and a failure report is sent to SMSC.

The HLR then informs the SMSC when the MS becomesThe HLR then informs the SMSC when the MS becomesavailable.available.


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MT SMS -DiagramMT SMS -DiagramWB BSNL-Circle1

NLDHLR

UK Subscriber

GMSC

VMSC/VLR

UK

HLRGMSC

SMSC

SMS

CdPA: 44-181-123456

SCCPCdPA: 44-181-SMSCofUK1CgPA: 919434099995(MSC/VLR)

SCCP

CdPA: 91-9434099995 MSC/VLR CgPA: 44-181-SMSCofUK1

1. MT-FSM

1. MT-FSM1.MT- FSM

1. MT-FSM

5. MT-FSM_resp5. MT-FSM_resp

5. MT-FSM_resp

SRI-SM

SRI-SM ACK


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PREPAID SYSTEMPREPAID SYSTEMPrepaid system adds few other nodes than the existing GSMPrepaid system adds few other nodes than the existing GSMnetwork.network.

It is the IN system which handles the prepaid subscriber.It is the IN system which handles the prepaid subscriber.

IN system consist of MainlyIN system consist of Mainly1.SCF1.SCF

2.SDP2.SDP3.PPAS3.PPAS4.IVR4.IVR

In MSC SSF module handles the prepaid call Scenario in MSCIn MSC SSF module handles the prepaid call Scenario in MSCside.side.


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GPRSGPRS

GPRS Core network consists of GPRS Core network consists of

SGSNSGSN

:Serving GPRS Support Node; the:Serving GPRS Support Node; the

gateway between the RNC and the coregateway between the RNC and the corenetwork in a GPRS/UMTS networknetwork in a GPRS/UMTS network

GGSNGGSN :Gateway GPRS Support Node; the:Gateway GPRS Support Node; thegateway between a cellular network and a IPgateway between a cellular network and a IPnetwork.network.


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GPRS RELATED LINKSGPRS RELATED LINKSGc-The interface between the GGSN and the HLR in a GSM/GPRS networkGc-The interface between the GGSN and the HLR in a GSM/GPRS network

Gd-The interface between the SGSN and the SMSC in a GSM/GPRSGd-The interface between the SGSN and the SMSC in a GSM/GPRSnetworknetworkGf-The interface between the SGSN and the EIR in a GSM/GPRS networkGf-The interface between the SGSN and the EIR in a GSM/GPRS network

Gi-The interface between the GGSN and the Internet in a GPRS networkGi-The interface between the GGSN and the Internet in a GPRS network

Gn-The interface between the GGSN and the SGSN in a GPRS networkGn-The interface between the GGSN and the SGSN in a GPRS network

Gp-The interfaces between the GGSN/SGSN and the Border Gateway in aGp-The interfaces between the GGSN/SGSN and the Border Gateway in aGPRS networkGPRS networkGr-The interface between the SGSN and the HLR in a GPRS networkGr-The interface between the SGSN and the HLR in a GPRS network

Gs-The interface between the SGSN and the MSC in a GSM/GPRS networkGs-The interface between the SGSN and the MSC in a GSM/GPRS network


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GPRS ATTACHGPRS ATTACH

SGSN

EIR

HLR

1.GPRS ATTACHREQUEST

2.Authenticationrequest

3.Athentication

res

4.Equipmentidentity check

5.Equipment idemtity check response

6.update location

7.ISD

8.ISDACK

9.GPRS attachaccepted


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CDMA (IS-95) TECHNOLOGYCDMA (IS-95) TECHNOLOGY Code-Division Multiple Access, a digital cellular technology that usesCode-Division Multiple Access, a digital cellular technology that uses

spread-spectrum techniquesspread-spectrum techniques

IS-95 CDMA system operates in 800 MhzIS-95 CDMA system operates in 800 Mhz

CdmaOne is the brand name of IS-95 technology from 1997.CdmaOne is the brand name of IS-95 technology from 1997.

CdmaOne is basically an air-interface standard.CdmaOne is basically an air-interface standard.

IS-95 uses Frequency division duplex.Forward link and reverse link IS-95 uses Frequency division duplex.Forward link and reverse link transmission occur in different frequency band.transmission occur in different frequency band.


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Duplex separation used in IS-95 is 45MhzDuplex separation used in IS-95 is 45Mhz

Carrier spacing is 1.25 MhzCarrier spacing is 1.25 Mhz

Forward link frequency: 824-849MhzForward link frequency: 824-849Mhz

Reverse Link frequency: 869Mhz-894MhzReverse Link frequency: 869Mhz-894Mhz

The forward link consists of Base station(BS) transmitter,radioThe forward link consists of Base station(BS) transmitter,radiochannel and the MS receiver.channel and the MS receiver.

CDMA ContinuesCDMA Continues


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CDMA ContinuesCDMA ContinuesCdmaOne system supports four different types of forward channelsCdmaOne system supports four different types of forward channels

##Pilot channel Pilot channel -is continuously transmitted by each CDMA carrier and is used by MS to identif -is continuously transmitted by each CDMA carrier and is used by MS to identifythe BS and to asses the suitability of the cell hand over.In this respect it may be likened to thethe BS and to asses the suitability of the cell hand over.In this respect it may be likened to theBCCH carrier in GSM system.BCCH carrier in GSM system.

##Synchronous channel Synchronous channel --ItIt allows MS to achieve time synchronization with BS and the network allows MS to achieve time synchronization with BS and the network ..

##Paging channel Paging channel --is used to page MSs to alert them to an incoming call.is used to page MSs to alert them to an incoming call.

##Traffic channel Traffic channel --are assigned to the users as required and they may carry speech or user data atare assigned to the users as required and they may carry speech or user data atbit rates of up to 9.6 kbps.bit rates of up to 9.6 kbps.


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Each forward channel on a CDMA carrier is assigned a different 64-bit Walsh code.Each forward channel on a CDMA carrier is assigned a different 64-bit Walsh code.

The reverse link radio path consists of the Mobile station(MS) transmitter,the radio channelThe reverse link radio path consists of the Mobile station(MS) transmitter,the radio channeland the base station(BS).and the base station(BS).

CdmaOne system supports two different types of radio channel on reverse link CdmaOne system supports two different types of radio channel on reverse link

##Access channel Access channel --as its name would suggest,is used by MS initially to access theas its name would suggest,is used by MS initially to access thenetwork,e.g. at call initiation or in response to a paging message.Each Base Station maynetwork,e.g. at call initiation or in response to a paging message.Each Base Station maysupport 32 access channels per forward link paging channel and the MSs within a CeLL aresupport 32 access channels per forward link paging channel and the MSs within a CeLL arepseudo-randomly distributed between the access channels.pseudo-randomly distributed between the access channels.


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CDMA ContinuesCDMA Continues

Access channel data are presented in the form of one 96-Access channel data are presented in the form of one 96-bit frame every 20 ms.Of this 96 bits,88 are used tobit frame every 20 ms.Of this 96 bits,88 are used tocarry information and remaing eight are encoder tailcarry information and remaing eight are encoder tailbits.bits.

## Traffic channelTraffic channel -are assigned to the individual user as-are assigned to the individual user asrequired.A reverse link traffic channel may carry speechrequired.A reverse link traffic channel may carry speech

and data at bit rates up to 9.6 kbps.and data at bit rates up to 9.6 kbps.


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The cdmaOne MS does not transmit a pilot signal as thisThe cdmaOne MS does not transmit a pilot signal as thiswould significantly decrease reverse link capacity.would significantly decrease reverse link capacity.

BS receiver uses RAKE receiver to demodulate the reverseBS receiver uses RAKE receiver to demodulate the reverselink signal from a particular MS.link signal from a particular MS.

MS handover process occur by measuring the strength of theMS handover process occur by measuring the strength of the

pilot channels signal from a BS other than its current BS.pilot channels signal from a BS other than its current BS.

CdmaOne system supports three main types of handover CdmaOne system supports three main types of handover


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CDMA ContinuesCDMA Continues ## Idle mode handover Idle mode handover -It occurs when an MS moves from the coverage area-It occurs when an MS moves from the coverage area

of one BS into the coverage area of a second BS while an MS is an idleof one BS into the coverage area of a second BS while an MS is an idlemode.mode.

## Soft handover Soft handover - is used between BSs having CDMA carriers with- is used between BSs having CDMA carriers withidentical frequency assignments.identical frequency assignments.

## Hard handover Hard handover - occur when a mobile is switched between two BSs- occur when a mobile is switched between two BSsusing different carriers.using different carriers.


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Simplified data flow for the access procedure of Simplified data flow for the access procedure of a mobile terminated call.a mobile terminated call.


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Basic cdmaOne diagram Basic cdmaOne diagram

CDMA 2000CDMA 2000


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CDMA 2000CDMA 2000 This is the evaluated 3G version of IS-95/cdmaOne technology.This is the evaluated 3G version of IS-95/cdmaOne technology.

CDMA2000 is an ITU-approved standard that was the first 3G technologiesCDMA2000 is an ITU-approved standard that was the first 3G technologies(October,2000).(October,2000).

provides advanced voice communications and high-speed data connectivity, includingprovides advanced voice communications and high-speed data connectivity, includingaccess to the Internet, mobile data applications and multimedia content.access to the Internet, mobile data applications and multimedia content.

Supports data services at minimum transmission rates of 144 kbps in mobile (outdoor)Supports data services at minimum transmission rates of 144 kbps in mobile (outdoor)and 2 Mbps in fixed (indoor) environments.and 2 Mbps in fixed (indoor) environments.

The world's first 3G commercial system was launched by SK Telecom (South Korea) inThe world's first 3G commercial system was launched by SK Telecom (South Korea) inOctober 2000 using CDMA2000October 2000 using CDMA2000


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CDMA2000 represents a family of standards andCDMA2000 represents a family of standards andincludesincludes>CDMA2000 1X>CDMA2000 1xEV-DO Technologies>CDMA2000 1xEV-DO Rev A

>CDMA2000 1xEV-DO Rev B>Ultra Mobile Broadband - UMB (CDMA20001xEV-DO Rev C)

CDMA 2000 iCDMA 2000 ti


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CDMA 2000 continuesCDMA 2000 continues

CDMA2000 builds on the inherent advantages of CDMACDMA2000 builds on the inherent advantages of CDMAtechnologies,such astechnologies,such as

>introduction of Orthogonal Frequency Division Multiplexing (OFDM>introduction of Orthogonal Frequency Division Multiplexing (OFDMand OFDMA)and OFDMA)

>advanced control and signaling mechanisms>advanced control and signaling mechanisms

>improved interference management techniques end-to-end Quality of >improved interference management techniques end-to-end Quality of

Service (QoS)Service (QoS)


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>new antenna techniques such as Multiple>new antenna techniques such as MultipleInputs Multiple Outputs (MIMO) and SpaceInputs Multiple Outputs (MIMO) and Space

Division Multiple Access (SDMA) toDivision Multiple Access (SDMA) toincrease data throughput rates and quality of increase data throughput rates and quality of serviceservice

>improving network capacity and reducing>improving network capacity and reducingdelivery cost.delivery cost.

CDMA2000 Advantages:CDMA2000 Advantages:


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CDMA2000 Advantages:CDMA2000 Advantages: >>Superior Voice qualitySuperior Voice quality

>>High-Speed Broadband Data connectivityHigh-Speed Broadband Data connectivity

>> Increased Voice and Data Throughput capacityIncreased Voice and Data Throughput capacity

>>Long-Term, Robust and Evolutionary Migration Path withLong-Term, Robust and Evolutionary Migration Path withForward and Backward CompatibilityForward and Backward Compatibility

>>Differentiated Value-Added Services such as VoIP, PTT,Differentiated Value-Added Services such as VoIP, PTT,Multicasting, Position Location, etc.Multicasting, Position Location, etc.


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>>Flexible Network Architecture with connectivity to ANSI-41, GSM-MAPFlexible Network Architecture with connectivity to ANSI-41, GSM-MAPand IP-based Networks and flexible Backhaul Connectivityand IP-based Networks and flexible Backhaul Connectivity

>>Flexible Spectrum Allocations with Excellent Propagation CharacteristicsFlexible Spectrum Allocations with Excellent Propagation Characteristics

>>Robust Link Budget for Extended Coverage and Increased DataRobust Link Budget for Extended Coverage and Increased DataThroughputs at the Cell EdgeThroughputs at the Cell Edge

>> Improved Security and PrivacyImproved Security and Privacy


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CDMA 2000 NETWORK DIAGRAMCDMA 2000 NETWORK DIAGRAM

UMTS/WCDMAUMTS/WCDMA


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UMTS/WCDMA UMTS/WCDMA UMTS (WCDMA)is a 3G evolution of GSM and GPRSUMTS (WCDMA)is a 3G evolution of GSM and GPRS

UMTS is one of the Third Generation (3G) mobile systems being developedUMTS is one of the Third Generation (3G) mobile systems being developedwithin the ITU's IMT-2000 framework within the ITU's IMT-2000 framework

The coverage will be provided by a combination of cell sizes ranging from 'inThe coverage will be provided by a combination of cell sizes ranging from 'inbuilding' Pico Cells to Global Cells provided by satellite, giving service to thebuilding' Pico Cells to Global Cells provided by satellite, giving service to theremote regions of the worldremote regions of the world

created a platform to converge the worlds of speech, data services and thecreated a platform to converge the worlds of speech, data services and theInternet to create a global market for mobile multimedia.Internet to create a global market for mobile multimedia.

UMTS is designed to increase a subscribers data rates and system capacity.UMTS is designed to increase a subscribers data rates and system capacity.


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Technical Features:Technical Features: Modulation Techniques used QPSK Modulation Techniques used QPSK

Multiple access technology used as CDMAMultiple access technology used as CDMA

Frequency reuse pattern : 1*1 (cell*sector)Frequency reuse pattern : 1*1 (cell*sector)

Maximum data rates supported: 384kbps to 2 mbpsMaximum data rates supported: 384kbps to 2 mbps

Both packect switch and circuit switch are supportedBoth packect switch and circuit switch are supported


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Radio channels are 5MHz wideRadio channels are 5MHz wide

ChipChip (fundamental unit of transmission in a(fundamental unit of transmission in a CDMACDMA system) rate of system) rate of 3.84 Mcps3.84 Mcps

Supports two basic modes of duplex, frequency division and timeSupports two basic modes of duplex, frequency division and timedivision. Current systems use frequency division, one frequency for division. Current systems use frequency division, one frequency for uplink and one for downlink. For time division, UMTS uses 15uplink and one for downlink. For time division, UMTS uses 15slots per radio frame.slots per radio frame.

ec n ca ea ures


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ec n ca ea urescontinues .continues .

>>Employs coherent detection on uplink and downlink based on the use of pilotEmploys coherent detection on uplink and downlink based on the use of pilot

symbolssymbols

>> Supports inter-cell asynchronous operationSupports inter-cell asynchronous operation

>>Variable mission on a 10 ms frame basisVariable mission on a 10 ms frame basis

>>Adaptive power controlAdaptive power control

>> Multiuser detection and smart antennas can be used to increase capacityMultiuser detection and smart antennas can be used to increase capacityand coverage.and coverage.


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>>initially poor coverage due to the time it takes to build ainitially poor coverage due to the time it takes to build anetwork network

>>for fully fledged UMTS incorporatingfor fully fledged UMTS incorporating Video on DemandVideo on Demand features, onefeatures, one base stationbase station needs to be set up every 11.5needs to be set up every 11.5kmkm (0.620.93(0.620.93 mimi ). While this is economically feasible). While this is economically feasible

in urbanin urban areas, it is infeasible in less populated suburbanareas, it is infeasible in less populated suburbanand rural areas.and rural areas.

>Requires huge frequency spectrum>Requires huge frequency spectrum

UMTS Network ArchitechtureUMTS Network Architechture


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UMTS Network ArchitechtureUMTS Network Architechture

UMTS N k A hi hUMTS N t k A hit ht


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UMTS Network ArchitechtureUMTS Network Architechture UMTS core network architechturally a GSM phase 2+UMTS core network architechturally a GSM phase 2+

Core network that is power up so that it can also handle the higher volume,higher bitCore network that is power up so that it can also handle the higher volume,higher bitrate,UMTS traffic.rate,UMTS traffic.

RNS(Radio network subsystem) is the additional part for UMTS network than GSM PhaseRNS(Radio network subsystem) is the additional part for UMTS network than GSM Phase2 + network.2 + network.

RNS consists of RNC (Radio network Controller) and Node B(part of User Equipment andRNS consists of RNC (Radio network Controller) and Node B(part of User Equipment andBase station)Base station)

The UMTS terrestrial Radio interface(UTRA) frequency duplex(FDD) mode is the W-The UMTS terrestrial Radio interface(UTRA) frequency duplex(FDD) mode is the W-CDMA radio interface of the UMTS.CDMA radio interface of the UMTS.

Carrier frequency is defined by the UTRA absolute radio frequency channelCarrier frequency is defined by the UTRA absolute radio frequency channelnumber(UARFCN).number(UARFCN).


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Physical ChannelsPhysical Channels there are two basic types of physical channels.there are two basic types of physical channels.

# # Dedicated ChannelsDedicated Channels -These are used by UEs for the duration of the call.There are two-These are used by UEs for the duration of the call.There are twoDedicated channels-Dedicated channels->>PCCHPCCH -Dedicated physical control channel carries-Dedicated physical control channel carries physical layer control informationphysical layer control information

>>DPDCHDPDCH -Dedicated physical data channel-Dedicated physical data channel transports the user traffic.transports the user traffic.

##Common channelsCommon channels -- these are used to carry information to the UEs within a cell and arethese are used to carry information to the UEs within a cell and areused by the UEs to access the network.used by the UEs to access the network. Common channels are of two types:Common channels are of two types: CommonCommonchannels are of two types:channels are of two types: 1.1. Down link common channelsDown link common channels

2.2. Uplink common channelsUplink common channels


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Down link common channelsDown link common channels

CPICH CPICH -Common Pilot Channel provides a common demodulation reference-Common Pilot Channel provides a common demodulation referenceover all or part of a cell.over all or part of a cell.

P-CCPCH P-CCPCH -Primary common control physical channel caries general network -Primary common control physical channel caries general network information.information.

S-CCPCH S-CCPCH -Secondary common control physical channel is used for paging and-Secondary common control physical channel is used for paging andpacket datapacket data

SCH SCH -Synchronisation channel is used by UE for its initial cell search-Synchronisation channel is used by UE for its initial cell search

AICH AICH -Acquisition indication channel controls the use of common uplink -Acquisition indication channel controls the use of common uplink channels.channels.

UP Li k h i lUP Li k h i l


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UP Link common physicalUP Link common physicalchannelschannels

PRACH PRACH -Physical Random Access Channels used by UEs-Physical Random Access Channels used by UEsinitially to access the network initially to access the network

PC-PCH PC-PCH -Physical Common Packet Channel allows-Physical Common Packet Channel allowsbursts of data to be transferred from UEs to thebursts of data to be transferred from UEs to thenetwork.CPCH is typically used for short,infrequent burstnetwork.CPCH is typically used for short,infrequent burst

of data where as dedicated channels are more suited toof data where as dedicated channels are more suited tolong burst.long burst.

UMTS Frame structureUMTS Frame structure


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UMTS Frame structureUMTS Frame structureThe duration of a frame is 10msThe duration of a frame is 10ms

One frame contains 15 slotsOne frame contains 15 slots

Each slot duration =0.667 msEach slot duration =0.667 ms

Each slot contains 2560 chipsEach slot contains 2560 chips

Chip rate=3.838Mchips/sChip rate=3.838Mchips/s

One super frame =72 frame= 720ms durationOne super frame =72 frame= 720ms duration

Difference between CDMA2000Difference between CDMA2000


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and UMTS technologyand UMTS technology>>Cdma2000 and UMTS were developed separately and are 2Cdma2000 and UMTS were developed separately and are 2

separate ITU approved 3G standardsseparate ITU approved 3G standards

>cdma2000 were developed to be backward compatible with>cdma2000 were developed to be backward compatible withcdmaOne but UMTS phones are not meant to be backwardcdmaOne but UMTS phones are not meant to be backwardcompatible with GSM systems.compatible with GSM systems.

>Cdma2000 is easy to implement because operators do not need>Cdma2000 is easy to implement because operators do not neednew frequencies but implementation of UMTS is very difficultnew frequencies but implementation of UMTS is very difficultbecause of its new requirement of wide range of frequency andbecause of its new requirement of wide range of frequency and

new implementation of the radio access network.new implementation of the radio access network.


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GSM Principles Com 4