LowComplexity TwoStage Detection Schemefor MIMO Systems

Thispaperprovides anapproach toreach anearRSdetector outperforms theMMSE V-BLASTdetector using maximumlikelihood performance, forMIMO systems, witha thesamecomplexity. strongly reduced computational effort. Thismethod isbased on Hence, therest ofthepaperwillbestructured asfollows: atwo-step detection. Thefirst detection stepwillbeperformed .' byusinaMMSEequalizr andasubsequntdeciion.uni. Insection II, wewill present theconsidered MIMO system byusing a MMSE equalizer anda subsequent decision unit.moe,adepantencsiy fadtco htsol x Thesecond stepisareduced search (RS)algorithm, thatis model, andexplain thenecessity ofadetector thatshould ex- applied onlyinaneighborhood ofthedetected symbols ofthe ploit thenoise correlation, caused bytheequalizer. Insection first step. Forcomplexity reasons only theleast reliable symbolsIII, wewill describe somedetection algorithms. Wewill start areprocessed bytheRSalgorithm. withthecommonML algorithm basedonajoint detection Thesimulation results showthatthisMMSE RS detector . . outperforms theMMSE V-BLASTdetector. Itprovides an ofallspatially transmitted symbols ofonetmeslot buildig improved performance using thesamecomplexity. thetransmit vector, thenthesymbolML algorithm based onoptimal symboldetection andfinally thenewproposed