摘要
ThispaperdescribesaLeastSquares(LS)channelestimationschemeforMIMOOFDMsystemsbasedontime-domaintrainingsequence.Wefirstcomputetheminimummeansquareerror(MSE)oftheLSchannelestimation,andthenderivetheoptimalcriteriaofthetrainingsequencewithrespecttotheminimumMSE.Itisshownthatoptimaltime-domaintrainingsequenceshouldsatisfytwocriteria.First,theautocorrelationofthesequencetransmittedfromthesameantennaisanimpulsefunctioninaregionlongerthanthechannelmaximumdelay.Second,thecross-correlationbetweensequencestransmittedfromdifferentantennasiszerointhisregion.Simulationresultsshowthattheestimatorusingoptimaltime-domaintrainingsequenceshasbetterperformancethanthatusingoptimalfrequencytrainingsequenceatlowsignal-to-noiseratio(SNR).Toreducethetrainingoverhead,asuboptimaltrainingsequenceisalsoproposed.Comparingwithoptimaltrainingsequence,ithaslowcomputationcomplexityandhightransmissionefficiencyattheexpenseoflittleperformancedegradation.
出版日期
2008年04月14日（中国期刊网平台首次上网日期，不代表论文的发表时间）
