Power Allocation for Multipair Massive MIMO FD Relay Systems with Low Resolution ADCs

To reduce energy consumption, relay stations with massive antenna arrays can be equipped with low resolution analog-to-digital converters (ADCs). Due to powerful loop interference in full-duplex (FD) relaying, however, low resolution ADCs generate strong quantization noise that has severe impact on the throughput of the system. In this paper, the throughput and energy efficiency of a FD decode-and-forward relay system with low resolution ADCs is investigated. Based on the mathematical analysis, a novel iterative power allocation scheme that mitigates the impact of the quantization noise via reducing the received LI power is proposed. The power allocation scheme aims at maximizing the end-to-end achievable rate by adjusting the per-link transmit powers at the relay. The numerical results show that compared to half-duplex relaying, using FD with the proposed power allocation scheme improves the system throughput and energy efficiency significantly.