Joint Beamforming Optimization and Power Control for Full-Duplex MIMO Two-way Relay Channel

TL;DR

This paper proposes a joint beamforming and power control scheme for full-duplex MIMO two-way relay channels, significantly enhancing data rates by optimizing relay and source parameters despite self-interference.

Contribution

It introduces iterative algorithms for joint optimization of beamforming and power control in full-duplex relay channels, improving end-to-end performance over existing methods.

Findings

Full-duplex relaying outperforms half-duplex in achievable data rates.

Proposed algorithms effectively optimize the rate region and sum rate.

Numerical results confirm significant performance gains.

Abstract

In this paper we explore the use of full-duplex radio to improve the spectrum efficiency in a two-way relay channel where two sources exchange information through an multi-antenna relay, and all nodes work in the full-duplex mode. The full-duplex operation can reduce the overall communication to only one phase but suffers from the self-interference. Instead of purely suppressing the self-interference, we aim to maximize the end-to-end performance by jointly optimizing the beamforming matrix at the relay which uses the amplify-and-forward protocol as well as the power control at the sources. To be specific, we propose iterative algorithms and 1-D search to solve two problems: finding the achievable rate region and maximizing the sum rate. At each iteration, either the analytical solution or convex formulation is obtained. We compare the proposed full-duplex two-way relaying with the conventional half-duplex two-way relaying, a full-duplex one-way relaying and a performance upper bound. Numerical results show that the proposed full-duplex scheme significantly improves the achievable data rates over the conventional scheme.