简介:DiscreteFourierTransform(DFT)basedmultiple-inputmultiple-outputOrthogonalFrequencyDivisionMultiplexing(MIMO-OFDM)isthefocusofwirelesscommunication,whichusescyclicprefixestoreducetheISI.Toimprovethespectrumefficiencyandsystemperformance,ComplexWaveletPacketTransform(CWPT)basedOFDMisusedtorealizetheMIMO-OFDMsystem.Forthegoodpropertyofcomplexwaveletpacketfunction,theCWPTbasedMIMO-OFDMsystemisbetterthantheDFTbasedMIMO-OFDMsystem,buttheCWPTbasedMIMO-OFDMschemehassomeadditionalcomplexity,andsimulationresultsshowthatthenewsystemcanimprovethesystemperformance.
简介:Vertically-layeredBellLaboratoriesLayeredSpace-Time(VBLAST)isoneofthemostpromisingtechniquesforrealizinghighspectralefficienciesoverwirelesslink.Inpreviouslypublishedwork,theperformanceofVBLASThasbeenprimarilyinvestigatedinuncorrelatedRayleighfadingchannels.Howeverinrealenvironmentssomecorrelationbetweenantennaelementscanbepresented.Inthispaper,westudytheimpactoftransmitcorrelationontheperformanceofVBLASTsystems.FinallyweprovidesimulationresultsdemonstratingtheimpactofspatialfadingcorrelationonthesymbolerrorrateofVBLAST.
简介:分析了慢衰落的独立同分布瑞利信道环境中,使用注水算法对MIMO信道容量ccdfs的影响.仿真结果表明,通过使用注水算法,可以显著的提高MIMO系统容量.随着MIMO系统发射端和接收端天线数目的增加,注水算法对系统容量的提高越显著.在低信号噪声环境中,注水算法对系统容量的改善越显著,随着信号噪声比的提高,注水算法对系统容量的影响越来越小.
简介:Apowerallocationschemeformulti-usermultiple-inputmultiple-outputorthogonalfrequencydivisionmultiplexing(MIMO-OFDM)systemswithchannelstateinformation(CSI)ontransmitterandreceiverispressed.Multi-userpowerallocationcanbedecoupledintosingleuserpowerallocationthroughoutnullspacemappingofmulti-userchannelandpowerallocationcanbeperformedthroughoutspatial-spectralwater-fillingforperuser.Todealwithmoreusersinsystemandfadingcorrelation,schedulingisperformedtomaintainthegainofpowerallocation.Theproposedschemecansubstantiallyimprovesystem'sspectralefficiencywithlowomplexity.Simulationresultsvalidatetheaccuracyoftheoreticanalyses.
简介:TheproblemofcheckingrobustD-stabilityofmulti-inandmulti-out(MIMO)systemswasstudied.Threesystemmodelswereintroduced,i.e.multilinearpolynomialmatrix,polytopicpolynomialmatrixandfeedbacksystemmodel.Furthermore,theconvexpropertyofeachmodelwithrespecttotheparametricuncertaintieswasestablishedrespectively.Basedonthis,sufficientconditionsforD-stabilitywereexpressedintermsoflinearmatrixinequalities(LMIs)involvingonlytheconvexvertices.Therefore,therobustD-stabilitywastestedbysolvinganLMIoptimalproblem.
简介:CapacityofMIMOLAS-CDMAsystemsundermulti-pathfadingchannelswithtwodifferentcorrelatingmodelswerestudiedinthepaper.Influencesofthetwomodelsparametersoncapacitywereanalyzed.Thenumericalresultspresentthat:accordingtotheVariousScatteringEnvironmentscorrelatingmodel,whentheinner-elementsdistanceofantennasarrayislargethan0.5λ,correlationalmostdoesnottakefromthesystemcapacity;fortheSalz-Wintercorrelatingmodel,thespreadangleatreceiveristheotherkeyfactor,italsoinfluencethesystemcapacitygreatly.