Reliability based Reduced-Complexity MMSE Soft Interference Cancellation Mimo Turbo Receiver

A reduced-complexity minimum mean square error (MMSE) soft interference cancellation (SIC) based multiple-input multiple-output (MIMO) turbo receiver is proposed. In this new proposal, the computational complexity intensive part of the MMSE SIC detector is ignored if the reliability of the a priori information is larger than a specific threshold. As the co-antenna interference (CAI) of MIMO system can be cancelled out with very high probability at higher iteration numbers, the computational complexity can be effectively reduced. Compared with those existing schemes which simply replace the MMSE filter with match filter (MF) at iteration stages, this new proposal takes the reliability of the a priori information into account and thus can reduce the computation complexity at the cost of negligible performance loss. Meanwhile, it is very flexible for this proposal to make a tradeoff between the performance and the computational complexity through changing the threshold of reliability. Simulation results confirm the advantages of this scheme.