Massive MIMO Full-Duplex Relaying with Optimal Power Allocation for Independent Multipairs

TL;DR

This paper investigates massive MIMO full-duplex relaying with optimal power allocation, demonstrating improved interference suppression, energy efficiency, and end-to-end performance in multi-pair communication systems.

Contribution

It introduces an optimal power allocation algorithm and evaluates the use of MMSE and zero-forcing filters in massive MIMO full-duplex relays with imperfect channel information.

Findings

Enhanced energy efficiency with MMSE filtering and OPA.

Significant interference suppression using massive arrays.

Improved BER performance in simulations.

Abstract

With the help of an in-band full-duplex relay station, it is possible to simultaneously transmit and receive signals from multiple users. The performance of such system can be greatly increased when the relay station is equipped with a large number of antennas on both transmitter and receiver sides. In this paper, we exploit the use of massive arrays to effectively suppress the loopback interference (LI) of a decode-and-forward relay (DF) and evaluate the performance of the end-to-end (e2e) transmission. This paper assumes imperfect channel state information is available at the relay and designs a minimum mean-square error (MMSE) filter to mitigate the interference. Subsequently, we adopt zero-forcing (ZF) filters for both detection and beamforming. The performance of such system is evaluated in terms of bit error rate (BER) at both relay and destinations, and an optimal choice for the transmission power at the relay is shown. We then propose a complexity efficient optimal power allocation (OPA) algorithm that, using the channel statistics, computes the minimum power that satisfies the rate constraints of each pair. The results obtained via simulation show that when both MMSE filtering and OPA method are used, better values for the energy efficiency are attained.