A low complexity blind space-time multiuser detector for multipath fading channel in DS/CDMA systems

In this paper, we propose a low complexity blind space-time multiuser detector for multipath fading channel in DS/CDMA systems. The conventional blind space-time multiuser detector uses MOE (minimum output energy) detectors to suppress interference and MRC (maximum ratio combiner) to obtain spatial and temporal diversity. But this receiver has disadvantage that the number of MOE detectors grows with the number of resolvable multipaths. The proposed space-time multiuser detector reduces the number of detectors using a MV (minimum variance) detection scheme. It is shown that one MV detector has the same performance as many MOE detectors as the number of multipaths. From this result, fewer blind multiuser detectors are required in the proposed scheme. Simulation results show that MV detector has the same performance as MOE detectors with MRC and the proposed scheme exhibits better performance than the conventional scheme.