Low-Complexity Multiuser Hybrid Precoding with Partially-Connected Architecture

Hybrid precoding has evolved into an essential technology in millimeter wave (mmWave) massive multiple-input multiple-output (MIMO) systems due to the low demand for the number of radio frequency (RF) chains. In this paper, in order to reduce the computational complexity of hybrid precoding, we propose a low-complexity two-stage multiuser hybrid precoding scheme. In the first stage, we focus on how to reduce the computational complexity under the premise of acceptable sum spectral efficiency loss. In the second stage, block diagonalization (BD) method is adopted to design digital precoder and classical water-filling method is utilized to address power allocation problem. Simulation results reveal that the proposed precoding scheme can achieve satisfactory level from the viewpoint of computational complexity, and meanwhile spectral efficiency can be guaranteed.