multistream distributed cophasing 2017 ribhu chopra参考.pdf

该【multistream distributed cophasing 2017 ribhu chopra参考 】是由【小舍儿】上传分享，文档一共【16】页，该文档可以免费在线阅读，需要了解更多关于【multistream distributed cophasing 2017 ribhu chopra参考 】的内容，可以使用淘豆网的站内搜索功能，选择自己适合的文档，以下文字是截取该文章内的部分文字，如需要获得完整电子版，请下载此文档到您的设备，方便您编辑和打印。:..1042IEEETRANSACTIONSONSIGNALPROCESSING,,,FEBRUARY15,2017MultistreamDistributedCophasingRibhuChopra,StudentMember,IEEE,,SeniorMember,IEEE,andRameshAnnavajjala,SeniorMember,IEEEAbstract?Inthispaper,?tsofrequiringa?xedpower(DCP)techniqueforphysicallayerfusionofmultipledatastreamstransmissionfromthenodes,isrobusttochannelestimationworkwithmultipledestinationnodes(DNs).errors,andit’sfeasibilityinpracticalimplementationiswellTheDNscaneitherbeconnectedtoafusioncenter(referredtoascentralizeddataprocessing;CDP)orprocessdataindependentlyestablished[5].Further,DCPisinherentlysecure:whenmul-municatewitheachotherviaarate-limitedlink(binestoasdistributeddataprocessing;DDP).Inthe?rststageofthisoverthechannelatagivendestination,itgetsincoherentlytwo-stagecophasingscheme,binedatanyunintendedreceiver,therebymakingithardDNsusingpilotsymbolstransmittedbythelatter;-,,?rststage,theDNstransmitknownpilotaleast-squares-basediterativealgorithmforblindchannelesti-symbolstotheSNsinaroundrobinfashion,usingwhichthemationinCDP?,wedevelopamessagepass-ingbasedblindchannelestimationalgorithmforDDP?,thesecondstage,theSNssynchronouslytransmittheirdatatotheproposedblindchannelestimationalgorithmachievesaprob-theDNsbypre-rotatingthedatabytheestimatedchannelphase,biningofthedataintendedtotheDNs,-pressionsfortheerrorprobabilityperformanceoftheproposedschemeworkswhenthechannelisquasi-staticandreciprocaluracyusing[5],[6].TransmissionofpilotsfromtheDNs,,hasmultipleadvantages:itsavespowerattheSNs;theDNsIndexTerms?Distributedco-phasing,datafusion,MIMO,blindaretypicallyconnectedtothemainsandarecapableoftrans-channelestimation,messagepassing,-starvedSNs;anditismoreef?,--work(WSN)applications,sationoftheinter-[2],[3].Here,asetofdistributedsensornodes(SNs)mondatatooneormoredestinationnodes(DNs),andinparticular,distributedco-municationfrommultiple(DCP),isaphysicallayertechniquethatcanbeusedtoprovidedistributedtransmittedantennastoadistantreceiveantennabininggainaswellasspatialdiversitygainforwas?rststudiedin[3],whereamasterslavearchitecturedatafusioninWSNs[4].InDCP,[3]wasextendedtofadingchannelsin[5].ManuscriptreceivedApril17,2016;revisedAugust26,2016andSeptemberDistributedtransmitbeamforming(DTB)systemsrequire30,2016;acceptedOctober17,,2016;carrierfrequencysynchronizationacrosstheSNs;itsfeasibilitydateofcurrentversionDecember9,[5]and[7].-frequencysynchronizationhasbeenachieved,theSNsneedmunications,Edinburgh,.,ordancewiththeDTB2016[1].,Bangalore560012,India(e-mail:ribhu@;cmurthy1@).,,Boston,MA02115DTBschemesisstudiedin[8].FeedbackbasedapproachesforUSA(e-mail:@).DTBinvolvingrandomanddeterministicphaseperturbationsinColorversionsofoneormoreofthe?guresinthispaperareavailableonlineathttp://ieeexplore..thedatasentbytheDNsarestudiedin[6]and[9],respectively,DigitalObjectIdenti?.2625263andtheirconvergenceisstudiedin[10].TheproblemofDTB1053-587X?,butrepublication/.:..CHOPRAetal.:MULTISTREAMDISTRIBUTEDCOPHASING1043hasalsobeenstudiedinthecontextofrelaypowerallocation3)Inspiredbythesigni?cantperformanceimprovementmunicatewithabasestationin[11].achievableevenintheabsenceofCSIattheDNs,weIn[12],theauthorsproposetouseDTBinacellularsystemwithdevelopaniterativeblindalgorithmforchannelestima-amulti-antennabasestationreceiverandasingle-antennausertionattheDNsforCDP-DCP.(SeeSectionIV.)-antennafusioncentersforWSNsareconsidered4)Motivatedbythesigni?cantgapbetweenperformanceofin[13]and[14].AsymptoticresultsarederivedtoshowtheCDP-DCPandDDP-DCP,wedevelopamessagepass-effectofmultipleantennasonaWSNsysteminthepresenceofingbasedchannelestimationalgorithmforinterferencesensingandchannelnoiseunderbothfullandphaseonlyCSImitigationatthereceivers.(SeeSectionV.)atthesensorsin[13].In[14],paretheperfor-5)WederiveapproximateanalyticalexpressionsforthemanceoftwodifferentdecisionfusionschemesforaMIMOprobabilityofsymbolerrorforbothCDP-DCPandDDP--PSKsignaling.(seeSectionVI.)In[15],theBERperformanceofDCPwithBPSKmodula-6)Viadetailedsimulations,mendedparedagainstthatofmaximumratiotransmission,systemparameterssuchasthedataandpilotsignal-to-censoredtransmission,(SNR),thenumberofDNs,andthenumberofassumedin[15]thattheCSIisnotestimatedatthefusioncen-sensornodestoachieveadesiredrateandreliability.(Seeter(FC),andtherefore,parisonislimitedtoconstantSectionVII.)modulusconstellationssuchasM-,MS-DCPalongwiththeproposedblindchannelnon-constantmodulusconstellationsin[16],anditisshownestimationalgorithmsisastrongcandidateforreliableanden-thathigherorderconstellationscanincreasetherateachiev-ergyef?,,[16]alsodevelopsthenotionofchannelestimationalgorithmscanberelevantinjointdatade-channelcorruptionforDCPsystemstoanalyticallycharacterizetectionandchannelestimationforotherchannelswithknownthe?;ourNotation:BoldfacelowercaseanduppercaselettersrepresentfocusinthispaperisonthescenariowheretheSNswishtosendvectorsandmatrices,,witheachSNhavingAaredenotedbyak,anda(k),respectively.(.),whereas(.)Tdenotesthetransposeoperation.·2and·Frespectivelyrepresentthe[·]andvar(·)representthemeanandvarianceofaInthepresentwork,-,--DCP(CDP-DCP),ordataprocessing-DCP(DDP-DCP),-rotatethedatasoastotoeachotherviaarate-,-?rststage,mondataeachoftheKDNsbroadcastMppilotsymbolsinaroundrobinstreamsthatareavailableatallthesensornodestoKcor-,aswellasanalyzetheirperfor-coef?-,alltheSNssimultaneouslytransmitDCP(MS-DCP),wherethenodestransmitmultipleindepen--phasedtocoherentlyassumedthatthechannelcoherencetimeexceedsM=KMp+[4],[5],andthatthechannelsbetweentheDNsandareasfollows:theSNsarereciprocal[15].Notethat,withtheproposedDCP1)WederivethestatisticsoftheeffectiveMIMOchannelscheme,biningattheDNscanbeachievedonlymatrixarisingduetoMS-DCPwithmultipleDNs.(,itisassumedSectionII.))paretheinformationratesachievablebyMS-DCPnotedin[4]thatthephaseofsuchasystemoncesynchronizedagainstsingle-streamDCP(SS-DCP),.(SeeSectionIII.)thelthSNduringchanneluses(k?1)Mp+1throughkMp,:..1044IEEETRANSACTIONSONSIGNALPROCESSING,,,FEBRUARY15,2017transmissionstage,thereceivedsignalonkthDNis Nyk[n]=αk,lejθk,lxl[n]+vk[n],n=KMp+1,...,Ml=1 K=Nhkisi[n]+vk[n]i=1 K=Nhkksk[n]+Nhklsl[n]+vk[n](5)l=1,l=kwherevk[n]plexGaussiannoiseatthekthDNwithaperdimensionvarianceN0,and2 N1hki=αk,lexpjθk,l?θi,l(6)Nl==1,...,K,-vectornotation,(5)canequivalentlybeexpressedasjθk,lyl[n]=αk,leEp+wl[n]y[n]=NHs[n]+v[n],(7)n=(k?1)Mp+1,...,kMp(1)withy[n]=[y1[n]y2[n]...yK[n]]T,s[n]=[s1[n]s2[n]...sK[n]]T,v[n]=[v1[n]...vK[n]]T,andH∈CK×K,withitswhereEpisthepilotpoweroftheDNs,αk,listheRayleigh(k,i)thelementhkiasde?[|α|2]Ω,θistheuni-k,lk,lk,[n]isthezeromeancircularlysymmetriccomplexadditivewhiteGaussiannoisewithperdimensionTocharacterizethestatisticalpropertiesofthechannelmatrixN0H,letus?rstconsiderthecasewithperfectDCP,.,θk,l=θk,(ML)estimateofthephaseoftheInthiscase,thediagonalentriesofthechannelmatrixcanbewrittenash=1Nα,whereαareindependentkthDNatthelthSNis[15]kkNl=1k,lk,lRayleighdistributedrandomvariables().?kM?The(k,i)thoff-diagonalentry,k=i,ish=1Np{y[n]}kiNl=1?1n=(k?1)Mp+1lαexp(j(θ?θ)).Asbothθandθareuniformlyθk,l=tan??(2)k,lk,li,lk,li,lkMp{y[n]}distributed,therefore,theirdifferencealsohasauniformdistri-n=(k?1)Mp+,the(k,i)thentry,k=i,oftheeffectivechan-where{.}and{.},=1k,lphasesforeachoftheKDNs,sensorltransmitsxl[n],?nitepilotSNR,thephaseestimateθk, K?jθi,lerrorinthephaseestimatebetweenthekthDNandthelthsensorxl[n]=si[n]en=KMp+1,...,M,(3)?i=1nodeisθk,lθk,l?θk,,thediagonalentriesofthechannelmatrixcanbewrittenaswheresi[n]isthenthmodulationsymbo