Citation

Abstract

In the ongoing quest for high wireless communications bandwidth efficiency, adaptive arrays intended for the base station are being investigated as a means of allowing multiple users simultaneous access to a common frequency and time slot. The background theory for the corresponding spatial division multiple access signal processing problem is considered. A description of simulations undertaken for the receive array situation is given, and the results are presented and discussed. The results show that when comparing the LMS algorithm training time required for different numbers of users, the effect of the received SINR seems to dominate, in apparent contradiction to what the eigenvalue spread predicts. When examining the training time performance for a given number of users, the received SINR and eigenvalue spread are the dominant factors. A proposal for a prototype hardware implementation of a receive array system is given, and numerous aspects of its design are considered, including a discussion of the relevant characteristics of a physical antenna array design proposed for this system. The material in this project is considered new since there is not a significant body of work involving experiments with array processing hardware intended for spatial multiplexing, nor with the analysis and simulation of adaptive arrays in a fading environment.