Recursive Maximum SINR Blind Beamforming Algorithm for CDMA systems

Maximizing signal-to-interference plus noise ratio (SINR) at the output of beamformer significantly improves the performance of the receiver using an antenna array. In this paper, we propose a recursive maximum SINR (RMSINR) blind beamforming algorithm for coded-division multiple access (CDMA) systems. First, a blind beamformer algorithm called direct maximum SINR (DMSINR) that maximizes the SINR directly is introduced. Then, to reduce the computational complexity of the DMSINR algorithm, the RMSINR algorithm is developed, which achieves the maximum of SINR under a linear constraint in a recursive manner. In addition to a significant complexity reduction, as simulation results show, the RMSINR algorithm attains a very fast convergence rate with the high ability of tracking direction of arrival in time varying environments.