Spatio-temporal channel estimation techniques for multiple access spread spectrum systems with antenna arrays

A major advantage of spread-spectrum communication systems is their ability to exploit the multipath structure of the received signal. A standard RAKE receiver estimates the time delay, attenuation, and angle of arrival of each path and uses a maximum-ratio combiner to recombine different path signals. Antenna array structures were proposed to mitigate the effects of multipath by separating the paths in both time and spatial domains. New techniques for estimating the spatio-temporal characteristics of the channel for coherent direct-sequence spread-spectrum systems are proposed. The simulation results present the performance of such a multichannel estimator