LDPC編碼的分布式空時(shí)合作通信系統(tǒng).pdf

1、浙江大學(xué)碩士學(xué)位論文LDPC編碼的分布式空時(shí)合作通信系統(tǒng)姓名：董波申請(qǐng)學(xué)位級(jí)別：碩士專業(yè)：信息與通信工程指導(dǎo)教師：仇佩亮20060501浙江大學(xué)碩士學(xué)位論文LDPC編碼的分布式空時(shí)合作通信系統(tǒng)LDPCCodedDistributedSpaceTimeCooperativeCommunicationSystemAbstractDiversityisalleffectivetechniquetocombatmultipathfadingan

2、dcochannelinterferenceinthewirelesscommunicationsystemComparewiththetimeandfrequencydiversitySpacediversitygivesdramaticperformancegainswithouttheadditionalexpenditureoftransmissiontimeorbandwidthAnewformofsingleuserspac

3、ediversityforthedistributedcommunicationsystemhasbeenproposed，whichiscalled“cooperativediversity”DistributednodesinthewirelessnetworkarecollectedsothatthenodesformavirtualantennaarrayThen，thecooperationofthenodesisutiliz

4、edtoachievethesDacediversityThemostcornmorlcooperativediversityprotocolsalefixedrelaying，selectionrelayingandincrementalrelaying111erelayinthesystemCallemploydifferenttypesofprocessing，suchasampli鳥一andforward(AF)，decodea

5、ndforward(DF)ItisfoundthatdifierentprotocolshavedistinctdiversityordersSpacetimebasedcooperativediversitycallachievefullsDatialdiversityinthenumberofcooperatingterminalsInthisdissertation，wefirstintroducethecommoncoopera

6、tivediversityprotocolsAndthen，bystudying也econventionalonerelayandtworelaydis仃ibutedspacetimecooperative(DSTC)systems，weproposethetwelayDSTCsystemwithfeedbackinformationThespecificimplementationsoftheproposedsystemaredisc

7、ussedinbotlltheAFmodeandDFmodeTheproposedsystemutilizesthenodesinnetworkmoreefficientlysoitcanreducethetransmissionerrorandofferhigherdiversityorderbutthelocationoftherelayshasprofoundimpactonthesystemperformanceSpacediv

8、ersitycanbecombinedwithgooderrorcorrectingcodestoobtalnmoreexcellentperformanceThelowdenstiyparity—check(LDPC)codeisalinearblockcodenleperformanceoftheLDPCcodescangetclosetotheShannonlimit，andthecomplexityofthedecodingal

9、godthmislinearwiththecodelength’11lcconcatenationschemeofLDPCcodesandspace—timeblockcoding(LDPC—STBC)areanalyzedDuetotheadvantageoftheLDPCSTBCintheconventionalmulti。antenasystem，thisschemeisextendedtothedistributedcommun

10、icationsystem，andtheLDPCcodeddistributedspace—timecooperativesystem(LDPC—DSTC)isproposedIntheAFmode，thefixedrelayingprotocolisemployed，andseverlsignalprocessmgschemesareproposed；intheDFmode，theselectionrelayingprotocolsi

11、semployed，andthepucturedLDPCandthechangeofLDPCsetsareutilizedtoimplementtheproposedsystemTheLDPC—DSTCsystemcanofferboththediversitygainandcodinggainFinallytheoptimizationoftheLDPCcodesintheDSTCsystemsisdiscussedKeywords：