Robust Tomlinson-Harashima Precoding for Two-Way Relaying

TL;DR

This paper introduces a robust Tomlinson-Harashima precoding method for two-way relay networks that accounts for imperfect channel information and optimizes mean square error under power constraints.

Contribution

It proposes a novel TH precoding scheme that handles channel uncertainty and improves performance in two-way relay systems with multiple antennas.

Findings

The proposed scheme outperforms existing methods under imperfect CSI.

Simulation results confirm the robustness and efficiency of the new precoding approach.

The method effectively minimizes mean square error within power limits.

Abstract

Most of the non-linear transceivers, which are based on Tomlinson Harashima (TH) precoding and have been proposed in the literature for two-way relay networks, assume perfect channel state information (CSI). In this paper, we propose a novel and robust TH precoding scheme for two-way relay networks with multiple antennas at the transceiver and the relay nodes. We assume imperfect CSI and that the channel uncertainty is bounded by a spherical region. Furthermore, we consider the sum of the mean square error as the objective function, under a limited power constraint for transceiver and relay nodes. Simulations are provided to evaluate the performance and to validate the efficiency of the proposed scheme.