User Collaboration for Interference Cancellation on Multi-User MIMO Communication Systems

Recently, multi-user multiple-input multiple-output (MU-MIMO) systems with spatial precoding have been widely studied. Although they offer various advantages, these systems require accurate downlink channel state information (CSI) at the transmitter and limits the mobility of user terminals. In this paper, we consider MU-MIMO systems which employ collaborative interference cancellation (CIC) between users for interference suppression. In this technique, neighboring user terminals share their received signals without decoding and equivalently increase the number of their receive antennas. The performances of the MU-MIMO systems with CIC are evaluated through field experiments for both minimum mean square error (MMSE) and maximum-likelihood detection (MLD) detection algorithms.