Low-Complexity Partially-Connected Hybrid Precoding for Massive MIMO Systems

Hybrid precoding is a promising solution for millimeter-wave (mmWave) massive multi-input multi-output (MIMO) systems. Most prior hybrid precoding algorithms have too high complexity to apply to actual systems. This paper presents a low-complexity partially-connected hybrid precoding algorithm. By directly utilizing phase angle information of the channel matrix, the algorithm at the analog precoding stage requires no complicated calculation and has the lowest complexity among the prior analog precoding algorithms known to the authors. Then the digital precoding is obtained through singular value decomposition (SVD) of the equivalent channel matrix. Simulation results show that the proposed design can achieve a satisfactory achievable rate and is also insensitive to imperfect channel state information (CSI) in mmWave channels.