Paper Title
Performance Analysis of Hybrid Precoding in Massive Multiuser MIMO Systems with Different Channels

Abstract
Massive multiple-input multiple-output (MIMO) is deployed to offer good capacity improvement and performance gain, but at the cost of high complexity of the hardware. In order to implement the task of hardware reduction, a double stage precoding scheme is proposed in this paper to approximate the performance of the well-known baseband zero forcing (ZF) precoding, which is considered generally as an optimum linear precoding methodology in MIMO systems. The proposed hybrid precoding structure which is actually a two-stage precoding is named as Phased ZF (PZF). The principle is that it applies phase-only modification first at the RF processing domain and then the ZF precoding of low dimension is performed on the effective channel as seen from the baseband. The Rayleigh fading channels, sparsely scattered millimeter wave (mm wave) channels and Nakagami-m fading channels are used for simulations of both FC-ZF and PZF all achieving desirable performances. Keywords - Massive MIMO, Hybrid Precoding, RF Chains, MM Wave, Spectral Efficiency, Fading Channels