Performance-Improved UCD-Based Hybrid Precoding for Millimeter-Wave Massive MIMO Single User Systems

Abstract

Hybrid precoding scheme can significantly reduce the number of radio frequency (RF) chains and the huge energy consumption in mmWave massive MIMO systems. Most existing hybrid precoding papers are based on singular value decomposition (SVD) or geometric mean decomposition (GMD). The GMD-based hybrid precoding scheme can avoid the complicated bit allocations in SVD-based method, because it decomposes the channel into several identical SNR subchannels. However, the GMD-based method will suffer from considerable capacity loss at low SNR in mmWave systems. To overcome this shortcoming, we can combine the hybrid precoding structure with uniform channel decomposition (UCD). In this paper, we propose the UCD-based hybrid precoding for mmWave massive MIMO single user systems. Simulation results verify that the proposed UCD-based hybrid precoding scheme outperforms the conventional SVD-based and GMD-based hybrid precoding schemes, because it achieves much higher spectral efficiency and lower bit error rate (BER) at low SNR systems.