Enhanced Simplified Maximum Likelihood Detection (ES-MLD) in multi-user MIMO downlink in time-variant environment

摘要

Support for a large number of users is required for the next generation wireless access systems and very high channel capacity must be achieved. The Multiuser-MIMO (MU-MIMO) technique has attracted much attention because of its high spectrum efficiency. However, in downlink MU-MIMO, channel state information (CSI) estimation error occurs in a time varying environment and the transmission quality is degraded. In this paper, we propose a new transmission and decoding method based on simplified maximum likelihood detection (S-MLD), which was proposed for single user MIMO systems. Since the dimensions of the signal path search space are expanded by adding interference signal space to the desired signal space, the proposed method is robust against the interference caused by the channel variation in MU-MIMO. The effectiveness of the proposed method is confirmed by computer simulation.