A space-time chip semiblind multiuser receiver based on LMS algorithms

A low complexity space-time chip semiblind multiuser receiver based upon an adaptive mixing parameter and adaptive step-size for MIMO STBC downlink MC-CDMA with CPICH systems and without CP is proposed. The receiver exploits information from training and desired user signals for updated the algorithm. Information from training and blind modes are combined using an adaptive mixing parameter LMS algorithm. The AS-LMS algorithm is incorporated in a semiblind, which in turn improves the performance of the receiver in frequency-selective fading channel. The detection requires only the knowledge of the desired user code matrix. The simulation results show that the mixing parameter adapts depending on the number of activated users in the system. As a result the performance of the proposed semiblind receiver outperforms in the SINR existing space-time chip semiblind and training-based receivers in dynamic channels.