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Agenda.GSM900/DCS1800.TheGSMNetwork&AirInterface.TechnicalBasics.SpeechCoding.TypesofChannel.MakingaPhoneCallGlobalSystemforMobile(GroupeSpecialMobile)GSM1982GroupeSpecialMobile?iscreatedwithinCEPT1986APermanentNucleusissetup1987Mainradiotransmissiontechniquesarechosen,basedonprototypeevalution(1986)1989GSMbecomesanETSItechnicalcommitte1990Thephase1GSM900specificationsarefinalized1991Firstsystemsarerunning1992AllmajorEuropeanGSM900operatorsbegincommercialoperatorGSMDevelopmentHistory•SpeechServices•DataServices•ShortMessageServices(SMS)•SupplementaryServices•SubscriberIdentityModule(SIM)•SecurityFunctionGSM/DCS1800FunctionalitiesRFAspects•TDMA•0.3GMSKModulation•BurstPowerTransmission•NeighbourCellsMeasurement•Hopping•Uplink/DownlinkDTx•BER&ReceiverTestingGSM900GSM900DCS1800DCS1800PCS1900Uplink890to880to1710to1710to1850to915MHz915MHz1785MHz1785MHz1910MHzDownlink935to925to1805to1805to1930to960MHz960MHz1880MHz1880MHz1990MHzARFCNrange1to1240to124and512to885512to885512to810975to1023TX/RXSpacing45MHz45MHz95MHz95MHz80MHz(Freq.)TX/RXSpacing3Timeslots(Time)ModulationData270.833kbit/sRateFramePeriod4.615msTimeslotPeriod576.9usBitPeriod3.692usModulation0.3GMSKChannelSpacing200KHzTDMAMux8MSMaxPower20W(8Wis8W8W1W1Wmaxinuse)MSMinPower13dBm5dBm4dBm0dBm0dBmMSPower5to190to150to1530,31,0to15ControlStepsVoiceCoderBit13kbit/s13kbit/s13kbit/s13kbit/s13kbit/sRate6.5kbit/s6.5kbit/sGSM900/DCS1800/PCS1900GSMFrequencyRange•890-915MHzUplink/MSTransmit•935-960MHzDownlink/BSTransmit•DuplexOffset45MHz•ChannelSpacing200kHz•Channelnumbering1-124•TransmissionSpeed270KbitsDCS1800FrequencyRange•1710-1785MHzUplink/MSTransmit•1805-1880MHzDownlink/BSTransmit•DuplexOffset95MHz•ChannelSpacing200kHz•Channelnumbering512-885•TransmissionSpeed270KbitsGSMPrimaryBand890900910920930940950960Freq45MHzUplink(MobiletoBase)Downlink(BasetoMobile)DCS1800PrimaryBand17101735176017851800182518501875Freq95MHzUplink(MobiletoBase)Downlink(BasetoMobile)CarriersattheborderoftheGSMband890.2890.4890.6890.8FreqGSMband200kHzCarriersattheborderoftheDCS1800band1710.21710.41710.61710.8FreqDCS1800band200kHzGSMNetworksBSCBTSBTSBTSBSSBSCBTSBTSBTSBSSMSCMSCOMCOMCADCNMCVLRVLRHLRAUCEIRInterfacetoothernetworkMSGSMNetworksTerminology:MS-MobileStation(移动台)BSS-BaseStationSystem(基站系统)BTS-BaseTransceiverStation(基站收发台)BSC-BaseStationController(基站控制器)MSC-MobileSwitchingCentre(移动业务交换中心)OMC-OperationsandMaintenanceCentre(操作与维护中心)NMC-NetworkManagementCentre(网络管理中心)AUC-AuthenticationCentre(鉴权中心)HLR-HomeLocationRegister(归属位置寄存器)VLR-VisitorsLocationRegister(来访位置寄存器)EIR-EquipmentIdentityRegister(设备标识寄存器)MSCBSCBSCBSCPSTNBTSBTSBTSAirInterfaceAbisInterfaceSS#7SS#7GSMInterfaceMSGMSKModulation110010110010PSKGuassianFilterSpectrum200kHzFcFc+67.708KHzFc+67.708KHz+67.708KHz-67.708KHzDataType?0DataType?1Modulation401234567123456FrequencyAmplitudeARFCNTimeslotPhysicalChannelisanARFCNandTimeslotTDMAandFDMATDMAandFDMATerminology:FDMA-FrequencyDivisionMultipleAccessTDMA-TimeDivisionMultipleAccessARFCN-AbsoluteRFChannelNumberTS-TimeslotPhysical-TheCombinationofaTSnumberChannelsandARFCN.Logical-AreMappedonPhysicalChannelsChannels10us10us10us10us8us8us3311575726148ActiveBits,546.42us147UsefulBits542.8us-70dB-30dB-6dB+4dB-6dB-30dB-70dBTol-1.0dBTol+1.0dBGSMTDMAPowerBurstPowerTimeTemplate542.8us/147Bits1081010810TimePower-700dBUpperLimitLowerLimitActualusNormalBurstPowerTimeTemplate321.23us/87Bits1081010810TimePower-700dBUpperLimitLowerLimitActualusAccessBurst87bitsUplink&DownlinkDownlink/MSReceive5670123456701342067012345671342Uplink/MSTransmit5Uplink&DownlinkARFCN02473601350614725312645724603571321045670123456700345670123451ARFCNUPLINKDOWNLINK45MHz.UplinkLagsDownlinkby3Timeslotperiods.UplinkandDownlinkusesameTimeslotNumber.UplinkandDownlinkusesameChannelNumber(ARFCN).UplinkandDownlinkusedifferentbands(45MHzapartforGSM900)FrequencyHoppingMODCouplerSwitchSynthRegisterControlUplinkBS1BS2MonitoringRXLevRXQualDownlink165124165124HomeBS20msBlocksSpeechCoderBitsOrdered260Bits260Bits5013278.RELPandLTPCoderRELP-Residual-ExcitedLinearPredictionCoderLTP-LongTermPrediction.ConvertsSpeechtoLowDataRate.20msSpeechmakes260Bits.Output13kbit/sVeryImportantBitsImportantBitsOtherBitsSpeechCoderErrorCorrectionTypeIa50TypeIb132TypeII7850132783TypeIaCRCTypeIbTypeIIBlockCode256625663478Re-ordering37878Halfrateconvolutionalcode456Bitsfrom20msofSpeechTypeIaTypeIbTypeIbTypeIaTailTypeIICRC262BitsIn456BitsOutDiagonalInterleaving456Bitsfrom20msofSpeech456Bitsfrom20msofSpeech575757575757575757575757575757575757575757575757575757575757TCHTrafficChannel(TCH)BurstsCarryTwo57BitsBlocks(114)Each120msofSpeech=456x6=2736bits2736/114=24burstsI.e.24frames(mobiletransmitsonceperframe)Multiframehas26framesin120msThereare2spareframes厖OneSACCH,oneIdlewww.3722.cn中国最大的资料库下载SpeechtoRadio/RadiotoSpeechChannelcodingSpeechDigitizingandSourcecodingInterleavingBurstformattingCipheringModulationChanneldecodingSpeechSourcedecodingDe-interleavingBurstformattingDecipheringDemodulationMSCamponFlowChartMSTurnOnMSsearcheschannelsandordersbysignalstrengthMSStongestBCCHF