Algebraic Solution for Beamforming in Two-Way Relay Systems with Analog Network Coding

TL;DR

This paper presents an algebraic approach to optimize beamforming in two-way relay systems with analog network coding, significantly reducing computational complexity while maintaining high performance.

Contribution

It introduces a novel algebraic formulation for beamforming optimization, replacing complex semidefinite programming with simple algebraic equations solvable by numerical methods.

Findings

Reduced computational complexity compared to SDP-based solutions

Provides a robust beamforming solution with high performance

Applicable to systems with perfect CSI and analog network coding

Abstract

We reduce the problem of optimal beamforming for two-way relay (TWR) systems with perfect channel state infomation (CSI) that use analog network coding (ANC) to a pair of algebraic equations in two variables that can be solved inexpensively using numerical methods. The solution has greatly reduced complexity compared to previous exact solutions via semidefinite programming (SDP). Together with the linearized robust solution described in (Aziz and Thron, 2014), it provides a high-performance, low-complexity robust beamforming solution for 2-way relays.