MIMO DFT-S-OFDM系統(tǒng)中的信道估計和迭代檢測譯碼技術(shù)研究.pdf

1、東南大學(xué)碩士學(xué)位論文MIMODFTSOFDM系統(tǒng)中的信道估計和迭代檢測譯碼技術(shù)研究姓名：龔希陶申請學(xué)位級別：碩士專業(yè)：通信與信息系統(tǒng)指導(dǎo)教師：高西奇20070301ABSTRACTABSTRACTDFTSpreadoFDM(DFTSoFDM)isthetransmissionschemcwhichallowsnexiblealocationofsubca玎iersandimproVedcoVerageowingtothelowpeak_

2、to—aVeragepowerratjo(fHPR)featLlrecomparabletosingle—ca喇ertransmissionsystemsEfncientlinkperfbmanceisgainedwtlenfkquencydomainequaljZa面onisexploitedatthereceiVerendTherefore，DFTSoFDMhasbeenpmposedby3GPPasthepromisingsche

3、mefnE己JTRAupIinktransmissionMuItipIeinputmultipleouIput(M1MO)systemo行erssignificamimproVementInperfoHllanceandcapacityandbecomesthekeyschemeinwirelessInob訂ecommunicationChannelestimationandtheiterativereceiverinMIMODFT_S

4、OFDMsystemsarethefocusesofthjsdissertati鋤TheaccuratechannelestimationisessentjaItoimproVetIleperfonnallceofiterativereceiVetThepilotaidedchanne】estimadonisjnVeStjgatedinthjsdissertationFirSny，mest】1lctLlreandgeneralionof

5、pilotsequencesarethorou曲】yaIlalyzedwimregardtothesubf‰estmctureFurthe瑚ore，chatlneles“mationinmefrequencyselectjVechannelsisjnVestigatedbothinthescenariOsofsingjetraIlsmitantennaaIldMIMosystems：theleastsquare(Ls)andmjnimu

6、mmeansquareerror(MMsE)channelestim撕onsarecondhcted，lhena船rtheDFTbasedoversafnplingntclpolationa11dtimedomaininterpoIation，challIlelfrequencyresponsesestimationinlongblockareobtamedComparedwithconventionalDFr_basedchannel

7、estimationschemes，theproposedalgorithmsestimateboththeoccupiedsubcarriersandtheVinualsubcarriersinShortblockThereforc，theleak唔ee圩色ctofchannelilllplllseresponseisdecreasedMSEanalysisa11dnumericalresultsshowthatinlowmobmty

8、eⅡv由]nment，TheBERandMSEperfbnTlancesofMMSE—basedchanneles廿mation印pmacht110seofideaIchaTlnelestimation；whjlethechaIlIleltrackingperformanceunderperfomlsforfbtchaIlIlelVarjatoninahi曲mobilityenVironment，thereforecausesthede

9、gradationofBERperfoml柚ceHoweveLTheBERperfonnanceofMMSE七asedcha|lneleslimationstiIIoutperfbnnsLSbaSedchanneIestimationwithapparemgainFinally，theiterativedetectionaflddecodingforspatialmu】tiplexing(SM)andspace—timeblockcod

10、e(STBC)codedDFTSOFDMsystemsarejnVestigatedByutilizingpmpeniesofcyclcprenxbasedcransmissionsystem，theLinearMMSE(LMMSE)somInputsoftouIput(SIso)detectjonispmposedinSMcodedDFT_S—OFDMSystem，thenthebIockwisejterativedelecliona

11、nddecodngisconductedThedetectjonalgonthmisfur[hersimpli稈edjnmu】tiuserSTBCcodedDFT_S—oFDMsystembyexp】oitlngt11epmpertiesofSTBCstmctureSimula“onsshowlhatthepmposediteratiVedetectjona11ddecodingsigni右ca工ltlyimproVetheBERper