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

Full-Duplex (FD) communication can revolutionize wireless communications as it doubles the spectral efficiency and offers numerous other advantages over a half-duplex (HD) system. In this paper, we present a novel and practical joint hybrid beamforming (HYBF) and combining scheme for millimeter-wave (mmWave) massive multiple-input-multiple-output (MIMO) multi-user FD system for weighted sum-rate (WSR) maximization. All the devices are assumed to have a limited dynamic range (LDR), and we adopt an impairment-aware HYBF approach. We also present a novel interference and self-interference (SI) power allocation scheme to include the optimal power allocation. The analog processing stage is assumed to be quantized, and we consider both the unit-modulus and unconstrained cases. Compared to the traditional designs, the proposed design considers the joint sum-power and the practical per-antenna power constraints. To model the non-ideal hardware of a hybrid FD transceiver, we extend the traditional LDR noise model to mmWave. Our HYBF design relies on alternating optimization based on the minorization-maximization method. We investigate the maximum achievable gain of a hybrid multi-user FD system with different levels of the LDR noise variance and with different numbers of radio-frequency (RF) chains. Simulation results show that our HYBF scheme can significantly outperform the fully digital HD systems with only a few RF chains. We also show that amplitude manipulation at the analog stage can improve the performance when the number of RF chains is small.