A beamformer for CDMA with enhanced near-far resistance

The spatio-temporal array-receiver (STAR) achieves good performance in CDMA with multiple receiving antennas where the interference can be characterized as AWGN uncorrelated with the signal. To enhance its near-far resistance in correlated noise environments, we introduce optimal combining of the spatio-temporal components. Nearly as good performance can be obtained with a low complexity adaptive beamformer combination of the antenna and multipath diversity branches. Simulation results indicate that the modified STAR manifests significant gain in near-far resistance over its original version, more so with more branches. They also suggest that exploiting additional temporal correlation fingers as interference references can further improve near-far resistance in poor diversity situations.