Decision feedback MLSE for spatially multiplexed MIMO frequency selective fading channel

A new decision feedback maximum likelihood sequence estimation (DF-MLSE) scheme for spatially multiplexed MIMO frequency selective fading channel has been proposed. A single trellis processor is required in the proposed receiver instead of multiple N_T parallel processors as required in existing low complexity receivers, where N_T is the number of transmitter antennas. The bit error rate (BER) performance of the proposed algorithm is the same as standard MLSE, but the computational complexity has been reduced significantly. For a model MIMO system (four transmitter and four receiver antennas) the computational complexity has been reduced by 95% in comparison to standard MLSE exploiting the proposed detection algorithm. Unlike the decision feedback equaliser (DFE) and the delayed decision feedback sequence estimation (DDFSE), the proposed algorithm has no signal-to-noise ratio (SNR) penalty while achieving the same BER performance as standard MLSE.