Multiuser receiver design for MC-CDMA systems with quasi-orthogonal STBCs

Multiuser receiver detection is examined in this paper for quasi-synchronous multi-carrier code-division multiple-access (MCCDMA) multiple-input multiple-output (MIMO) system with space-time block codes (STBC). Considering quasi-orthogonal STBC scheme that involves four transmit and multiple receive antennas, the linearly constrained minimum variance (LCMV) and eigenspace receivers are employed for symbol detection. The weight analyses are performed such that the computational cost of receiver design is reduced. Besides, the forward backward averaging technique is presented to enhance the performance of multiuser detection. Finally, numerical simulations are given to evaluate and compare the proposed channel estimation and symbol detection techniques.