Beam pattern selection diversity technique for DS/CDMA reverse link

A beam pattern selection diversity technique combined with transmit power control (TPC) is proposed for suppressing high level interference from high bit rate terminals to low bit rate terminals in the uplink of DS/CDMA systems. The proposed system employs a delay profile measurement based beamforming technique to calculate the optimum beamform for the reception of signals from terminals. To reduce the amount of computation required to control the beam directivity, the proposed system calculates the optimum beam directivity for only a limited number of terminals located far from the base station, and signals from the rest of the terminals are demodulated by selecting one of the most reliable adaptive array combined signals. TPC is employed to compensate for the performance degradation caused by such suboptimal control. Computer simulation confirms that the proposed technique is effective in suppressing high level interference with a relatively low signal processing load