Smart antenna applications to wireless systems.

摘要

Recent studies show that for a broad variety of interference-dominated wireless systems including mobile, personal communications, and wireless PBX/LAN networks, the system performance and capacity can be significantly increased by the use of spatial diversity (antenna array).; The dissertation addresses both theoretical and experimental aspects of a Smart Antenna system which exploits the spatial dimension in signal processing for wireless communication networks to improve system operating parameters, e.g., capacity, quality, coverage, cost, etc. The chief aim of this research is to develop new techniques to solve several key implementation problems arising from the integration of an antenna array with a conventional communication system. In particular, we study the uplink source recovery and the downlink selective transmission problems which constitute the groundwork of smart antenna operations.; For uplink source recovery, our focus is on blind identification, i.e., signal and channel estimation based solely on the antenna outputs. The elimination of the training sequence has a potential to provide a more flexible and yet reliable communication link, while keeping the protocols of existing wireless systems. For downlink selective transmission, we investigate the relation between uplink and downlink channels and address mainly the optimal interference suppression problem.; Also presented in this work are channel capacity studies and feasibility analyses for smart antenna systems.