基于mimo-ofdm系统的正交空时分组码+单位抗衰落复正交空时分组码级联的turbo码 毕业论文外文翻译

《基于mimo-ofdm系统的正交空时分组码+单位抗衰落复正交空时分组码级联的turbo码 毕业论文外文翻译》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。

1、外文资料（一）OnOrthogonalSpace-TimeBlockCodesforMIMO-OFDMSystemsSpace-timecodeinmobilecommunicationsystem,andorthogonaldesinginmultiple-antennasscnemearedicsussed.Bythemethods,dataisencodedusingaspace-timeblockcodeandissplitintoseveralstreamswhicharesimultaneouslytransmitt

2、edbyantennas.Soamaximum-likelihooddecodingalgorithmcanbeusedatthereceivertoachievethemaximumdiversityorderIntroductionMostworkonwirelesscommunicationshadfocusedonhavinganantennaarrayatonlyoneendofthewirelesslink—usuallyatthereceiver.SeminalpapersbyGerardJ.Foschiniand

3、MichaelJ.Gans[1],Foschini[2]andEmreTelatar[3]enlargedthescopeofwirelesscommunicationpossibilitiesbyshowingthatforthehighly-scatteringenvironmentsubstantialcapacitygainsareenabledwhenantennaarraysareusedatbothendsofalink.Analternativeapproachtoutilizingmultipleantenna

4、sreliesonhavingmultipletransmitantennasandonlyoptionallymultiplereceiveantennas.ProposedbyVahidTarokh,NambiSeshadriandRobertCalderbank,thesespace–timecodes(STCs)achievesignificanterrorrateimprovementsoversingle-antennasystems.Theiroriginalschemewasbasedontrelliscodes

5、butthesimplerblockcodeswereutilizedbySiavashAlamouti,andlaterVahidTarokh,HamidJafarkhaniandRobertCalderbanktodevelopspace–timeblock-codes(STBCs)[4].STCinvolvesthetransmissionofmultipleredundantcopiesofdatatocompensateforfadingandthermalnoiseinthehopethatsomeofthemmay

6、arriveatthereceiverinabetterstatethanothers.InthecaseofSTBCinparticular,thedatastreamtobetransmittedisencodedinblocks,whicharedistributedamongspacedantennasandacrosstime.Whileitisnecessarytohavemultipletransmitantennas,itisnotnecessarytohavemultiplereceiveantennas,al

7、thoughtodosoimprovesperformance.ThisprocessofreceivingdiversecopiesofthedataisknownasdiversityreceptionandiswhatwaslargelystudieduntilFoschini's1998paper.AnSTBCisusuallyrepresentedbyamatrix.Eachrowrepresentsatimeslotandeachcolumnrepresentsoneantenna'stransmissionsove

8、rtime.Here,sijisthemodulatedsymboltobetransmittedintimeslotifromantennaj.TherearetobeTtimeslotsandnTtransmitantennasaswellasnRrecei