Constrained Space-Time MOE Detection for CDMA Wireless Systems
Zhi Tian, Kristine L. Bell, Harry L. Van Trees · 2001
This paper provides a comprehensive treatment of space-time blind minimum output energy (MOE) detection in multipath code division multiple access (CDMA) channels with receiver antenna arrays. Assuming no knowledge of the spatial response characteristic of the propagation channel, we investigate constrained space-time MOE detection schemes, present a series of constraint strategies, and develop both centralized and decentralized space-time receiver structures, using fixed and optimized constraints. Under each receiver structure, the detection design is based on a generic constraint design framework that illustrates the tradeo#s between performance and computational complexity in a unified manner. Di#erent constraint parameters for temporal and spatial combining are derived to minimize the performance degradation due to imprecise knowledge of the space-time multipath channel. Adaptive recursive least squares implementations are provided for each of the spacetime detectors. Simulations are provided to compare the performance of the derived detectors.