Multiuser detection in CDMA MIMO systems with timing mismatch.

摘要

In this thesis, we investigate the impact of mismatch in time-delay estimations between transmit-receive antenna pairs in a multiuser CDMA MIMO communication system. We first formulate a robust space-time decorrelator (STD) by decomposing each substream with rectangular chip pulse shapes into two virtual substreams. A multistage successive interference cancellation (SIC) implementation of the robust STD that requires no ordering is then proposed to reduce complexity and increase capacity. The proposed receiver integrates a receiver diversity combining procedure, residual error estimation, amplitude averaging and soft-decision cancellation to reduce error propagation and noise enhancement. It is demonstrated that the proposed robust space-time SIC (RSTSIC) achieves significant performance improvement over the STD when delay estimation error is present, and its performance is close to that of the STD with perfect timing estimation. (Abstract shortened by UMI.)