Interference suppression consisting of pre-distortion filtering with transmit diversity

The paper analyzes several schemes to combat both MAI and fading in the downlink. We propose a new pre-distortion (PD) filtering technique, which can be used to combat multiple access interference (MAI), combined with selective transmit diversity (STD) for high data rate transmissions over frequency selective Rayleigh fading channels. The proposed PID scheme considers a RAKE receiver. By pre-distorting the signals to be transmitted by the base station (BS) with a minimum variance (MV) algorithm, the orthogonality between the desired signal and all interfering signals can be improved. With the PD, the increase in performance is achieved with a small increase in power processing at the BS, avoiding any need to increase complexity at the mobile station (MS).