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 recent work has been done on space-time processing in which multiple transmit/receive antennas are used in conjunction with coding to exploit spatial diversity. In this paper, 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-genaeration (3G) wideband CDMA standards, we use the Alamouti 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.