Abstract

In this thesis, we study the performance of adaptive Uniformly Spaced Circular Array (UCA) and Uniformly Spaced Linear Array (ULA) utilized in the base station of CDMA systems. In these systems, the desired signal becomes much stronger than the interference signals after chip correlation by a factor of the processing gain. Further, simple blind algorithms and the real-time implementation can be applied to improve bit error rate in various interference scenario. The performance of several algorithms is compared in AWGN channel, Rayleigh Flat Fading channel, and Frequency Selective Fading channel considering angle spread, phase errors and mobile tracking. In wireless communications, propagation effects of the transmitted signals result in delay spread, angle spread, Doppler spread and multipath in mobile radio channel. Different antenna array geometries may cause different responses to the received signals. Our study shows that the UCA is less sensitive to the angle spread than the ULA does, consequently the UCA exhibits better performance than the ULA in the multipath environment with angle spread, which is almost certainly the case in the uplink of CDMA communication systems.