Multiceli interference coordination strategy based on hybrid channel information

Abstract

Inter-cell interference (ICI) limits the throughput of multicell massive MIMO systems. Considering the large-scale array at base stations, high array gain can be obtained by analog beamforming based on statistical channel information. In this paper, we propose an interference coordination strategy based on both statistical and instantaneous channel information to mitigate ICI in multicell massive MIMO systems. We propose an enhanced Joint Spatial Division and Multiplexing (JSDM) precoding to mitigate ICI by cooperative beamforming implemented by the two-stage precoding based on channel covariance matrices and global effective channel state information (CSI). We also present the way to implement the precoding in practical systems without perfect effective CSI. Simulation results show that the proposed precoding can effectively mitigate ICI, thus provide remarkable gain in the downlink throughput and improve the fairness among users over the traditional one.