For multiple-input multiple-output(MIMO)space-time coded architecture based on distributed antenna system(DAS)

signals from different transmit antennas arrive asynchronously to the receiving antennas due to the random channel propagation delays among different links.Consequently

linear detection algorithms may be more complicated because of the complexity of inter-symbol interference.Furthermore

the optimal linear detection algorithm would not be obtained directly by applying minimum mean square error(MMSE)criterion.Focusing on the problem above

this paper supposes the optimal linear detection algorithm

named Joint-MMSE detection

in which maximum ratio combining(MRC)is implemented firstly

subsequently MMSE detection

and finally the diversity order by bounding bit error rate(BER).According to the simulation results

MRC-MMSE is authentically the optimal linear detection algorithm of MIMO with distributed transmit antennas.