Practical Hybrid Beamforming for Millimeter Wave Massive MIMO Full Duplex with Limited Dynamic Range

In this paper, we present a novel hybrid beamforming (HYBF) design to maximize the weighted sum-rate (WSR) in a single-cell millimeter-wave (mmWave) massive multiple-input-multiple-output (MIMO) full duplex (FD) system. Compared to the traditional HYBF designs, we consider the joint sum-power and the practical per-antenna power constraints. The multi-antenna users and the hybrid FD base station (BS) are assumed to be suffering from the limited dynamic range (LDR) noise due to non-ideal hardware. The traditional LDR noise model is first extended to the mmWave and an impairment-aware HYBF approach is adopted. A novel interference, self-interference (SI) and LDR aware optimal power allocation scheme for the multi-antenna uplink (UL) users and the hybrid FD BS is also presented. The analog processing stage is assumed to be quantized, and both the unit-modulus and the unconstrained cases are studied. The maximum achievable gain of a multi-user mmWave FD system over a fully digital half duplex (HD) system with different levels of the LDR noise variance and different numbers of the radio-frequency (RF) chains is investigated. Simulation results show that the proposed HYBF design outperforms the fully digital HD system with only a few RF chains at any LDR noise level. The advantage of having amplitude control at the analog stage is also examined and additional gain is evident when the number of RF chains at the FD BS is small.