A reverse link beamforming based on simplex downhill algorithm for time-varying channel environments

A new beamforming method based on the simplex downhill optimization process is presented for the CDMA system reverse link. The proposed system performs code-filtering at each antenna for each user. It is shown that for fast fading channels, conventional square error based cost functions can yield poor results. A new method is proposed based on a variation of the SINR cost function coupled with optimal time-varying channel estimation to improve signal tracking. The new beamforming method gives lower computation and faster convergence properties than existing algorithms in a fast fading environment. The simulation results show that the proposed algorithm has a better BER performance in the case of the time-varying channel.