移动通信与仿真TDSCDMA

TD-SCDMA吴伟民电子与信息工程系1TD-SCDMAEvolutionPathTD-SCDMA:FrequencyBandTD-SCDMAVsW-CDMASystemParamtersFrameStructurePhysicalChannelsSynchronizationChannelsDownlinkSynchronizationUplinkSynchronizationMultiplexingChannelsJointDetectionBatonHandoverN-FrequencyCell

TD-SCDMAEvolutionPath3GPPLCRTDD（R4）LCRTDD（R5）LCRTDD(R6)LCRTDD(R7)LTETDD

CCSAChinaCommunicationsStandardsTD-SCDMAStageIII（R7）OFDM/SC-FDMAAssociationTD-SCDMAStageI（R42023/03）

NFrequency CellTD-SCDMAStageII（R5）

Multi-carrierStandardization2023ShortTermEvolution

2023LongTermEvolutionTD-SCDMA:FrequencyBand175517851850188019201980202320252110217023002400SatelliteSatellite

30MHz60MHz

40MHz

15MHz100MHzFDDTDDTD-SCDMAVsW-CDMACode

C3

C2FrequencyUser3

User2

User1C1CDMATime

1userW-CDMA1CodeSpreadingFactorMax512CodesTD-SCDMASpreadingFactorMax16CodesTDSCDMAVsW-CDMAcodetimeUser1User2W-CDMAULDLfrequency5MHz190MHz

code

time16codeTD-SCDMAfrequencycanbeusedTDSCDMAVsW-CDMA3simultaneoustechnologiesTDSCDMAVsW-CDMAAvantagesofTD-SCDMA:☺Efficientspectrumallocation☺Supportforasymmetrictrafficandservices☺EquivalentChannelintheUplinkandDownlink(Fadingandmulti-path)☺Eliminationofintra-cellandinter-cellinterference.☺Lowpowerconsumption☺Batonhandover☺LowcostfortheRFfrontendDisdavantagesofTD-SCDMA:▼Requiresaccuratesynchronization▼Limitedsupportforhighspeed/mobilityusers▼Complexandexpensivetechnologies7TDSCDMASystemParameters

ParameterCarrierbandwidthCarrierspacingChiprateDuplextypeMultipleaccessschemeFramelengthNumberofslots/sub-framesRadioframelengthRadio-subframelengthDatamodulationVoicedatarateReceiverSpreadingfactorsMaxdatarateperuser(theoretical)SynchronizationAntennaprocessing

Value

1.6MHz 1.6MHz 1.28Mcps TDD TDMA,CDMA,FDMA 10ms 10ms 5ms QPSKor8-PSK 8Kbit/s Jointdetector(rakeinUE) 1,2,4,8and16 2Mbps DownlinkanduplinkSmartantennawithbeamformingTDSCDMA:FrameStructure

Chiprate:1.28Mcps

10msRadioframe#i 5ms

Radioframe#i+15ms

Bandwidth:1.6MHz

Modulation:QPSK/8PSK/16QAM

Duplex:TDDDwPTS:DownlinkPilotTimeSlot(96chips)Sub-frame#1Sub-frame#2UpPTS:UplinkPilotTimeSlot(160chips)DwPTSGP1UpPTSTS0TS1TS2TS3TS4TS5TS6352chips

Data1

144chipsMidamble352chips

Data2GP316chipsFirstSwitchPoint:GP1(96chips),SecondSwitchPoint:afterTS1DLULUL/DLGPGP16CP--

TDSCDMA:PhysicalChannelDPCH:DedicatedPhysicalChannel,Rec25.221§5A.2

BurststructureofthetrafficburstformatDatasymbols 352chipsMidamble144chipsDatasymbols 352chips864*Tc

16SF=16codechannelpertimeslotperCarrierSpreadingfactor(Q)

1 2 4 8 16Numberofsymbols(N)perdatafieldinBurst

352 176 88 44 22ThecontentsofthetrafficburstformatfieldsChipnumber (CN)

0-351 352-495 496-847 848-863Lengthoffieldin chips

352 144 352 16Lengthoffieldin symbols

cftable8A cftable8A

Contentsof fieldDatasymbols MidambleDatasymbolsGuardperiod1st23PP31strdPP

TDSCDMA:PhysicalChannel

PositionoftheTFCIcodewordinthetrafficburstincaseofnoTPCandSSpartofTFCIcodewordndpartofTFCIcodewordrdpartofTFCIcodeword4thpartofTFCIcodewordGGDatasymbolsMidambleDatasymbolsDatasymbolsMidambleDatasymbolsTimeslotx(864Chips) Sub-frame5msTimeslotx(864Chips) Sub-frame5ms

RadioFrame10msPositionoftheTFCIcodewordinthetrafficburstincaseofTPCandSSpartofTFCIcodewordSS

TPCsymbolssymbols 2ndpartofTFCIcodewordpartofTFCIcodeword SSsymbolsTPCsymbols 4thpartofTFCIcodewordGGDatasymbolsMidambleDatasymbolsDatasymbolsMidambleDatasymbolsTimeslotx(864Chips)Timeslotx(864Chips)Sub-frame5msRadioFrame10msSub-frame5msGP01

TDSCDMA:PhysicalChannel

PositionofTPCinformationinthetrafficburstindownlinkanduplinkSSsymbol(s)TPCsymbol(s)DatasymbolsMidambleDatasymbols144chips864Chips

CodingoftheSSforQPSKTPCBitPatternforBPSKSSBitsSScommandMeaningbTPCTPCMeaning00'Down'Decreasesynchronisationshiftbyk/8commandTc'Down' 'Up'DecreaseTxPowerIncreaseTxPower1101

'Up'‘Donothing’Increasesynchronisationshiftbyk/8TcNochangeTPCBitPatternfor8PSKCodingoftheSSfor8PSKTPCBits

000 110TPCcommand

'Down' 'Up'MeaningDecreaseTxPowerIncreaseTxPowerSSBits

000SScommand

'Down'

MeaningDecreasesynchronisationshiftbyk/8Tc110011

'Up'‘Donothing’Increasesynchronisationshiftbyk/8TcNochangeTheSSisutilisedtocommandatimingadjustmentby(k/8)TceachMsub-frames,whereTcisthechipperiod.ThekandMvaluesaresignalledbythenetwork.field(1)TDSCDMA:PhysicalChannelDPCH:TimeslotFormats

TimeslotformatsfortheDownlink

QPSK

TimeslotformatsfortheUplink

SlotFormat #

0 1 2 22 23 24

SlotFormat #

0 1 2 10

25 40 69Spreading Factor

16 16 16 1 1 1Spreading Factor

16 16 16 8

4 2 1Midamble length (chips)

144 144 144 144 144 144

Midamble length (chips)

144 144 144 144

144 144 144

NTFCIcodeword

(bits)

0 4 8 8 16 32

NTFCI codeword

(bits)

0 4 8 0

0 0 32NSS&NTPC

(bits)

0&0 0&0 0&0 32&32 32&32 32&32

NSS& NTPC

(bits)

0&0 0&0 0&0 0&0

0&0 0&0 32&

Bits/slot

88 88 88 1408 1408 1408Bits/slot

88 88 88 176

352 704 1408

NData/Slot

(bits)

88 86 84 1340 1336 1328NData/Slot

(bits)

88 86 84 176

352 7041328

Ndata/data

(bits)

44 42 42 702 700 696

Ndata/data

(bits)field(1)

44 42 42 88

176 352 696

Ndata/data field(2)

(bits)

44 44 42 638 636 632Ndata/data field(2)

(bits)

44 44 42 88

176 352 63232t

TDSCDMA:PhysicalChannelDPCH:TimeslotFormatsSlotSpreadingMidambleNTFCINSS&Bits/sloNData/SlotNdata/dataNdata/data8PSKFormat #Factorlength(chips)codeword

(bits)

NTPC(bits)(bits)field(1)(bits)field(2)(bits)012111144144144

0 6120&00&00&0211221122112211221092106105610531053105610561053Timeslotformatsforthe Downlink&Uplink…

20 21 22 23 24…

16 16 16 16 16…

144 144 144 144 144…

0 6 12 24 48

…3&33&33&33&33&3…

132 132 132 132 132…

126 123 120 114 102…

66 63 63 60 54…

60 60 57 54 481

2

TDSCDMA:PhysicalChannel

‘CommonTransportChannels’ismappedontothe PrimaryCommonControlPhysicalChannels(P-CCPCH1andP-CCPCH2)

TheP-CCPCHsaremappedontothefirsttwocodechannelsoftimeslot#0withspreadingfactorof16cQk=16cQk=16BCHDatasymbols 352chipsMidamble144chipsDatasymbols 352chipsGP16CP

864*TcNoTFCIisappliedfortheP-CCPCH1st2P-GP16CP

TDSCDMA:PhysicalChannel

ThetimeslotandcodesusedfortheS-CCPCHarebroadcastontheBCH Inamulti--frequencycellS--CCPCHshallbetransmittedonlyontheprimary frequencypartofTFCIcodewordndpartofTFCIcodewordGDatasymbols

MidambleTimeslotx(864Chips)DatasymbolsTFCIisappliedfortheS-CCPCH

FixedSF=16Datasymbols 352chipsMidamble144chipsDatasymbols 352chips

864*TcNoTFCIisappliedfortheS-CCPCH

TDSCDMA:PhysicalChannel

TheRACHismappedontooneormoreuplinkphysicalrandomaccesschannels(PRACH). InsuchawaythecapacityofRACHcanbeflexiblyscaleddependingontheoperatorsneed.Datasymbols 352chipsMidamble144chipsDatasymbols 352chipsGP16CP

864*TcPRACHtimeslotformatsSpreading Factor

16 8 4SlotFormat #

0 10 25Inamulti-frequencycellthePRACHshallbetransmittedonlyontheprimaryfrequency.1129(LSB)7GP16CP

TDSCDMA:PhysicalChannel

TheFPACHisusedfortheacknowledgementofadetectedsignaturewithtimingandpowerleveladjustmentindicationtoanuserequipment. FPACHmakesuseofonecodewithspreadingfactor16,sothatitsburstiscomposedby44symbols.Thespreadingcode,trainingsequenceandtimeslotpositionareconfiguredbythenetworkandsignalledontheBCH.

Inamulti-frequencycelltheFPACHistransmittedontheprimaryfrequency.TheFPACHmayalsobealsotransmittedonthesecondaryfrequencyincaseofhandover.

FPACHinformation32bitsdescription

InformationfieldLength(inbits)SignatureReferenceNumber3(MSB)RelativeSub-FrameNumberReceivedstartingpositionoftheUpPCH(UpPCHPOS)TransmitPowerLevelCommandforRACHmessageReservedbits(defaultvalue:0)

SignatureReferenceNumber:bitsequence(000)correspondstothefirstsignatureofthecell;…;bitsequence(111)correspondstothe8thsignatureofthecell. RelativeSub-Frame:bitsequence(00)indicatesonesub-framedifference;…;bitsequence(11)indicates4sub-framedifference ReceivedstartingpositionoftheUpPCH:range0–8191 Transmitpowerlevelcommandistransmittedin7bitsDatasymbols 352chipsMidamble144chips 864*TcDatasymbols 352chipsTheFPACHusesslotformat#0,SF=16••••

TDSCDMA:PhysicalChannelsDwPTS(75us)GP1(75us)UpPTS(125us)GP2SYNC_DLSYNC_ULGP2TS0(32chips)(64chips)(128chips)(32chips)TS1DwPCH:DownlinkPilotChannel32SYNC_DLavalaiblecodes1cell<->SYNC_DLcodeUpPCH:UplinkPilotChannel

256SYNC_ULcodes 32Groups,8codespergroup

Inamulti-frequencycelltheDwPCHshallbetransmittedonlyontheprimary frequency. TheUpPCHistransmittedontheprimaryfrequency.TheUpPCHmayalsobetransmittedonthesecondaryfrequenciesincaseofhandover.()codesS1S20123

TDSCDMA:SynchronizationChannels

DownlinkPilotCHannel,Rec25.223§8.1ForthegenerationofthecomplexvaluedSYNC-DLcodesoflength64,thebasicbinarySYNC-DL

s=S1,s2,...,s64

SYNC-DLisQPSKmodulatedandthephaseoftheSYNC-DLisusedtosignalthepresenceof theP-CCPCH. TheSYNC-DLcodeisnotscrambled. Fourconsecutivephases(phasequadruple)oftheSYNC-DLareusedtoindicatethe presenceoftheP-CCPCHinthefollowing4sub-frames

SequencesforthephasemodulationfortheSYNC-DLName

Phasequadruple135,45,225,135

MeaningThereisaP-CCPCHinthenext4sub-framesTableAA.1:32BasicSYNC-DLCodes315,225,315,45ThereisnoP-CCPCHinthenext4sub-framesCodeIDSYNC-DLCodesof

length64B3A7CC05A98688E4 9D559BD2906067912CE7BA12A017C3A2 34511D20672F4712….28293031

…..D4354B2FE02361CC5383AB6C8A10CE84 D417A730F2F12244ABF0A0D905A939C4s0123456251252253254255

TDSCDMA:SynchronizationChannels

UplinkPilotCHannel,Rec25.223§8.2UpPCH:generationofthecomplexvaluedSYNC-ULcodesoflength128

s=(1,s2,...,s128)

TableAA.2:256BasicSYNC-ULCodesCodeID

…

SYNC-ULCodesoflength128C11C20F0D1807DB8859175B798EC094A91278068081EC8E74543DBC1C9AD423538F5AEE2E513DB12A663BA04160103E57AA8A0A210F12A1E4332F2EDD33011FCC180EA3B9BA1774EB9611BD249C4A508B072A2C839489D496B98CE9D0132FBC9 B2723EAC6EB01667F2B33961C8074234 ….68FC090C2221AA98BF0D24E85066EFC29E26CEC67832FC42A87E92FA1015212E ACD889634F79506F2582EA03240F2A07AA65407E1F4A33BF9A62860A3D6A4CC0B1B950AC76A608AA32D04B03C7FF24D3

TDSCDMA:SynchronizationChannelsCodeAllocation,Rec25.223§8.3

CodeGroupAssociatedCodesSYNC-DL IDSYNC-UL IDScramblingCode IDBasicMidambleCode IDGroup100...700123123Group218...1544...567567Group3231248...255124124125126127125126127Inamulti-frequencycell,primaryfrequencyandsecondaryfrequencyusethe samescramblingcodeandbasicmidamblecode.1234

TDSCDMA:DownlinkSynchronizationCellSearchSearchforDwPTSScramblingandMidambleCodeIdentificationControlMulti-frameSyncReadtheBCH•32SYNC_DLcodes •SYNC_DLcode->4BasicMidambleCode •Scramblingcode<->BasicMidambleCode •PhaseSequencesofDwPTSsTDSCDMA:UplinkSynchronizationBasedonDLsynchronizationEstablishULsynchronization

RandomAccess

Two-stepapproachUpPTSULTrafficSlots

SYNC_UL FPACH PRACHMaintainULsynchronization

Midamble SSSS

MidambleSYNC-UL ss

ULburstofUETDSCDMA:MultiplexingChannelsControlPlaneUserPlaneBCCHPCCHDCCHCCCHCTCHDTCH

LogicalChannelsMAClayerBCHPCHRACHFACHDCHTransportChannelsPHYlayerP-CCPCHS-CCPCHPRACHDPCH

PhysicalChannelsTDSCDMA:MultiplexingChannelsTFCI1+TFCI2+TFCI3+TFCI41CCTrCH

1fullframe(2sub-frames)

TransportChannel1PhysicalChannel1

TransportChannel2

CCTrCHPhysicalChannel2

TD-SCMDA1UEmayhaveupto 4CCTrCHsTransportChannel3EnergyTDSCDMA:JointDetectionMobileradiopropagationisaffected:multiplereflectionsdiffractionsattenuationsEachCDMAsignalisoverlaidwithallothersinthesameradiocarrierandthereceived(wide-band)signalcanbebelowthethermalnoise.SpreadSignalsReceivedSignal=Σ-EnergyofSpreadSignalsFrequencyAcorrelationreceiver(MatchedFilterCorrelator)is