Hybrid Precoding for Correlated Multi-User mm-Wave Channels Based on Beam Alignment

Hybrid analog-and-digital precoding in millimeter-wave (mm-wave) multiple-input multiple-output (MIMO) communications is a promising strategy to save cost with a minimal performance penalty. In this letter, a novel hybrid precoder (HP) design is proposed for correlated multi-user mm-wave communication scenarios. With a hybrid beamformer structure, the proposed solution can effectively align beams to cover the strongest paths of individual users, and suppress interference by iterative ping-pong beamforming (PPB) strategy. Experimental results demonstrate that the proposed scheme can obtain higher spectrum efficiency compared to existing HP designs in highly correlated channels.