In this project, flexible and robust models for mobile radio channels will be created and used in the analysis of joint detection and decoding algorithms and for throughput optimization of multiuser wireless systems. The research has three closely related thrusts. In the first component, fundamental issues in estimation, equalization and modeling of multipath fading channels will be addressed. Accurate models will be selected for rapidly time-varying mobile radio channels, and the impact of the nature of propagation on estimating channel coefficients will be investigated. A performance comparison of robust channel estimation and adaptive equalization techniques will be carried out, taking into account issues arising due to error propagation. Robust diversity combining techniques will be developed. The other two directions will utilize channel modeling and estimation techniques developed in the first component of this project. Reliable low complexity detection methods for multiuser systems with error control coding will be the focus of the second component. Joint equalization, multiuser detection, and decoding will be addressed taking into account the effects of interleaving and error propagation. In the third component, the throughput of realistic wireless spread spectrum packet radio networks (PRNs) with multiuser detection will be evaluated. In this work, accurate channel models, reliable joint detection and decoding methods, and antenna diversity techniques will be utilized to optimize the throughput. Receiver complexity, the coding-spreading trade-off, and access schemes will be considered in this optimization. The
