Deep Reinforcement Learning Based Beamforming for Throughput Maximization in Ultra-Dense Networks

Ultra-dense network (UDN) is a promising technology for 5G and beyond communication systems to meet the requirements of explosive data traffic. However, the dense distribution of wireless terminals potentially leads to severe interference and deteriorate network performance. To address this issue, beamforming is widely used to coordinate the interference in UDNs and improve receive gains by controlling the phase of multiple antennas. In this paper, we propose a multi-agent deep reinforcement learning (DRL) based beamforming algorithm to achieve more dynamic and fast beamforming adjustment. In the proposed algorithm, the agents inside beamforming controllers are distributively trained while exchanging partial channel state information (CSI) for better optimizing beamforming vectors to achieve maximized throughputs in UDNs. The evaluation results demonstrate that the proposed algorithm significantly improves the computation efficiency, as well as achieves the highest network throughput compared to several baselines.