Adaptive multi-sensor receivers for frequency selective channels in DS-CDMA communications systems

The performance of two adaptive multi-sensor least squares (LS) receivers for a frequency-selective fading channel are evaluated. These two receivers are preceded by a RAKE which combines the resolvable paths of each channel of the desired user before further interference suppression. In the first, a LS space-time filter is used to accomplish despreading and interference rejection simultaneously. The second is a spatial-temporal version of the partial despreading LS (prds-LS) as proposed in Singh and Milstein (1997). For the partial despreading structure, the number of coefficients are reduced compared to the LS structure. If the desired user´s channel coefficients are known, the multi-sensor prds-LS is very attractive for DS-CDMA systems with large processing gain in terms of both complexity and tracking performance.