Blind adaptive space-time multiuser detection with multiple transmitter and receiver antennas

The demand for performance and capacity in cellular systems has generated a great deal of interest in the development of advanced signal processing techniques to optimize the use of system resources. In particular, much work has been done on space-time processing in which multiple transmit/receive antennas are used in conjunction with coding to exploit spatial diversity. We consider space-time multiuser detection using multiple transmit and receive antennas for code-division multiple-access (CDMA) communications. We compare, via analytical bit-error-probability calculations, user capacity, and complexity, two linear receiver structures for different antenna configurations. Motivated by its appearance in a number of third-generation (3G) wideband CDMA standards, we use the Alamouti (see IEEE J. Select. Areas Commun., vol.16, p.1451-58, Oct. 1998) space-time block code for two-transmit-antenna configurations. We also develop blind adaptive implementations for the two transmit/two receive antenna case for synchronous CDMA in flat-fading channels and for asynchronous CDMA, in fading multipath channels. Finally, we present simulation results for the blind adaptive implementations