Adaptive channel estimation and interference suppression in space-time coded multiuser systems

In this paper, an adaptive interference suppression scheme for space-time coded multiuser systems is presented. We consider M synchronous co-channel users, each is equipped with N_r transmitting antennas. The receiver is equipped with N_r (≥ M) receive antennas. It is shown that the proposed scheme estimates the weights adaptively and suppresses the interference without any explicit knowledge of the channel and the interference. In addition, this interference cancellation scheme has less complexity than the minimum mean squared error (MMSE) scheme, while maintaining the same decoding complexity with acceptable performance degradation due to weight estimation errors.