Space-time coding for two-user MIMO systems with the PIC-SIC group decoding

For a two-user MIMO system, the decoding complexity of layered Alamouti code is high with the maximum-likelihood (ML) decoding while full diversity is achieved. Partial interference cancellation (PIC) and its combination with successive interference cancellation (PIC-SIC) group decoding, which group the symbols in one layered Alamouti code into several groups and decoding each group separately, provide low decoding complexity with sacrifice of full diversity. In this paper, we propose one space-time code for two-user multi-antenna systems with two antennas at each user and N(N ≥ 2) antennas at the receiver. Full diversity order 2N is proved to be achieved with the PIC-SIC group decoding by the analytical derivation of the symbol error rate. Simulation results presented confirms the derivation and its better bit-error rate (BER) performance over layered Alamouti code with the PIC and PIC-SIC group decoding.