(08.06.12 update) LTE_TDD_Uplink_Phy_Chan

LTETDDUplinkPhysicalChannel&ModulationJiangZhiningHuangWu2008-06-12AllRightsReserved©Alcatel-Lucent2006,#####2|LTETDDPhysicalLayerProcedure1UplinkoverviewAllRightsReserved©Alcatel-Lucent2006,#####3|LTETDDPhysicalLayerProcedureUplinkOverviewPhysicalchannelsPhysicalUplinkSharedChannel,PUSCHPhysicalUplinkControlChannel,PUCCHPhysicalRandomAccessChannel,PRACHPhysicalSignalsDemodulationReferenceSignal,DMRS–ForPUSCH–ForPUCCHSoundingReferenceSignalAllRightsReserved©Alcatel-Lucent2006,#####4|LTETDDPhysicalLayerProcedureUplinkOverview12/2/212,RBscULRBRBscULRBs,CP)(NNNNkTNtfkjlklleatsResourceelementmapperScramblingModulationmapperTransformPrecoderIFFTaddCP7.5kFrequencyShiftifftN212nje•Basebandsignal•TwiddlefactorPUSCHModulationmapperPUCCHRSgeneratorReferenceSignalwhereicibib,2mod)()()(~cellID9s14RNTIinit222NnncQPSK,16QAM,64QAMbitMPUCCHformatModulationscheme1N/AN/A1aBPSK11bQPSK22QPSK202aQPSK+BPSK212bQPSK+QPSK22bitMAllRightsReserved©Alcatel-Lucent2006,#####5|LTETDDPhysicalLayerProcedureUplinkOverview0m0m1m1m2m2m3m3mOnesubframe0PRBn1ULRBPRBNn•PUCCHResourceMappingPUCCHformatSetofvalueforlNormalcyclicprefixExtendedcyclicprefix1,1a,1b2,3,42,32,2a,2b1,53•DMRSlocationforPUCCH•PUCCHformat1/1a/1b•DMRSforPUCCH•format1/1a/1b•PUCCHformat2/2a/2b•DMRSforPUCCH•format2/2a/2bAllRightsReserved©Alcatel-Lucent2006,#####6|LTETDDPhysicalLayerProcedureUplinkOverview•PUSCH+DMRSforPUSCH+SRSResourceMapping•DMRSforPUSCH:l=3of2slotsofresourceblocksforPUSCH•Soundingreferencesignal:l=0persub-frameintheresourceblockforPUSCH•PUSCH•SoundingRS•DMRSforPUSCHAllRightsReserved©Alcatel-Lucent2006,#####7|LTETDDPhysicalLayerProcedureULRxoverviewRemoveCPFFTwithtwiddlefactorResourceElementDe-mapperDMRSChannelestimationFrequencyoffsetcompensationChannelestimationresultTimingadvancecommandEqualizationforPUSCHDemodulation(LLRcalculation)RateDe-matchingIDFTSINRmeasurementPUCCHDecodingCQI,ACK/NACKUserdataFrequencyoffsetestimationDemodulationRSEstimatedCFOChannelDe-interleaverDecoderTimingOffsetestimationChannelestimationresult(afterCFOcompensation)De-scramblingHARQ(softCombining)AllRightsReserved©Alcatel-Lucent2006,#####8|LTETDDPhysicalLayerProcedure2ULFrequencySynchronizationAllRightsReserved©Alcatel-Lucent2006,#####9|LTETDDPhysicalLayerProcedureImpactsofFrequencyoffsetFrequencyoffsetcanleadtoInter-Channel(sub-carrier)Interference(ICI)Thereceivedfrequencyresponseissubjecttointerferencefromtheneighboursub-carriers456789x105-0.200.20.40.60.811/Tf•Perfectfreqsync•freqoffsetleadtoICIAllRightsReserved©Alcatel-Lucent2006,#####10|LTETDDPhysicalLayerProcedureULfrequencyoffsetestimationThetotalrangeoffrequencyoffsetintheULisrathersmallFractionalfrequencyoffsetestimationbasedonDMRS(orSRS)isenoughkHzecf22ms5.02,)10(R)3(R1M0k*kkpuschscllangleDMRS0.5msecDMRS)10(R0)3(R0)3(Rk)10(Rk)3(R1）（10R1sub-carrier3l10l……jePhasedifferencejePhasedifferencejePhasedifferenceAllRightsReserved©Alcatel-Lucent2006,#####11|LTETDDPhysicalLayerProcedureULfrequencyoffsetcompensationFFTNnje/21RxdataPUSCH/DMRSForuser1FFTNnje/22RxdataPUSCH/DMRSForuser2FFTRxdataPUSCH/DMRSForuser1FIRfilter1FIRfilter2PUSCH/DMRSForuser2FrequencydomainfilterComputationloadtoohighAllRightsReserved©Alcatel-Lucent2006,#####12|LTETDDPhysicalLayerProcedureULfrequencyoffsetcompensationfrequencyoffsetcorrectionsequenceWhereisthenormalizedfrequencyoffsetbasedonthecarrierfrequencyoffsetestimationresult.Ifissmall,theenergyofmainlyconcentrateonseveralpoints.ThisdecreasethenumberoftapsofFIRfilterThetapsoffiltercanbesetto3,4,5orhighervalueNkNjkeNkkNeDFTNnj/1/sinsin),(F/2kFAllRightsReserved©Alcatel-Lucent2006,#####13|LTETDDPhysicalLayerProcedure3ULTimingSynchronizationAllRightsReserved©Alcatel-Lucent2006,#####14|LTETDDPhysicalLayerProcedureULtimingoffsetThereareseveralfactorsleadingtoULtimingsynclossTimingdriftduetoUEmovingclosertoorawayfromtheeNodeBMultipathchannelchange(thestrongestpathchange)InaccurateUEoscillatorInitialtimingadvanceisacquiredafterthedetectionofRACHpreambleTimingoffsetshallbeestimatedperuserThetimingadvanceupdateperiodinLTE_ACTIVEstateTimingadvanceupdateperiodshallbeshortenoughtocopewiththeabovefactors–e.g.severalhundredmillisecondsmaybeenoughTAcommandshouldnotbetoofrequentinavoidofunnecessaryTAestimationerrorAllRightsReserved©Alcatel-Lucent2006,#####15|LTETDDPhysicalLayerProcedureTimingAdvance(TA)CommandForLTETDD,thetimingoffsetshallalsoconsidertheUL-DLtimingswitchingpoint.Thegranularityoftimeadvancecommandis16*Ts.•0•2•3•4•NB•UE•0•2•3•4TpTUDPUSCH/PUCCH•1TA=2Tp+TUD•1Tp•D•S•U•D•DTDUDwPTSUpPTSGPPUSCH/PUCCHRACHformat0RACHformat0TpAllRightsReserved©Alcatel-Lucent2006,#####16|LTETDDPhysicalLayerProcedureULtimingoffsetOption1.ThetimingoffsetcanbeestimatedatthetimedomainFirstperformIFFTofthechannelfrequencyresponse(withzeropadding)inordertogetthechannelpulseresponseatthetimedomainThechanneldelayprofilemainlyconcentratesatatimedomainwindow,thenfindthetimingoffsetofthiswindowOncet