Interference mitigation in MIMO interference channel via successive single-user soft decoding

This paper examines a practical way of mitigating interference in multi-input multi-output (MIMO) interference channel when each user is constrained to use a point-to-point code. It was recently shown that the capacity region of interference channel with point-to-point codes can be established by a combination of two schemes: treating interference as noise and joint decoding. In practice, a straightforward implementation of a joint decoding receiver could be significantly more complex than treating interference as noise. Thus, as a low-complexity approach to joint decoding, this paper proposes a successive single-user soft decoding receiver, which performs interference-aware detection with a priori log-likelihood ratio (LLR) and single-user soft decoding for every user successively. The proposed receiver is compared with a receiver treating interference as noise and a receiver performing interference-aware detection without a priori LLR and single-user decoding for the desired user only. Simulation results show that the proposed receiver significantly outperforms these existing receivers.