水声CDMA多用户通信系统仿真研究.pdf

27420104

:1006-9348(2010)04-0099-03

CDMA

和麟,孙超

(,710072)

:,

,(MIMO)

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1516dB14dB,,

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:TN9115:A

SimulationofCDMAMultiuserCommunicationSystem

forUnderwaterAcousticChannels

HELin,SUNhao

(InstituteofAcousticEngineering,NorthwesternPolytechnicalUniversity,XianShanxi710072,hina)

ABSTRACT:Theperformanceofdirect-sequencecode-divisionmultiple-access(DMA)syetemdependspri

marilyontheorthogonalityofthecodes,whichisdestroyedbythemultipathpropagationoftheunderwateracoustic

channel.Inthispaper,aDMAmultiuserunderwateracousticcommunicationsystemisproposed.AMIMOdecision

-feed-backequalizerisemployedtocanceltheintersymbolinterference(ISI)andsupressmultiple-accessinter

ference(MAI).Thissystemhashighleveloftoleranceforthenear-fareffectduetoanextraspreadspectrumgain.

Smiulationsareperformedtostudytheperformanceonnear-fareffectsupressionandtmiedelaybewteenusers.Smi

ulationresultsshowthatiftheweakeruserssignalpoweris14dBlowerthanthestrongerone,thereceivercanstill

distinguishallthethreeusersdatawithouterrorwhenspreadingfactoris15andinputSNRis16dB.

KEYWRDS:Underwateracousticcommunication;Multiuser;DMA;MIMOequalization;Near-fareffect

(DMA)MAI,(ISI)

1[3]

,DMA

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