Interference-alignment-embedded iterative beamforming design for multi-cell MIMO broadcasting

In this paper, we consider downlink multi-cell multi-user multi-antenna systems, where the users experience interference from adjacent cells as well as other users in the same cell. We design an iterative beamforming algorithm towards sum-rate maximization. Specifically, we propose an interference-alignment-embedded structure in the iteration, where a two-layer precoder approximately aligns the intra-cell interference with the inter-cell interference, and a max-SINR detector maximizes the achievable data rate. Simulation results show that the algorithm converges rapidly and achieves superior performance in noise-limited environments.