Instantaneous Relaying for the 3-Way Relay Channel with Circular Message Exchanges

TL;DR

This paper investigates a 3-user relay channel with circular message exchange, modeling it as an interference channel with receiver side information, and extends coding schemes to improve performance in Gaussian channels.

Contribution

It models the relay channel as an interference channel with side information and extends Han-Kobayashi coding to this setting, demonstrating performance gains.

Findings

Extended Han-Kobayashi coding scheme for this channel

Numerical results show improved performance over existing methods

Application to Gaussian channels with amplify-and-forward relaying

Abstract

The 3-user discrete memoryless multi-way relay channel with circular message exchange and instantaneous relaying is investigated. We first show that this channel is effectively a 3-user interference channel with receiver message side information for every fixed (and instantaneous) relay mapping. Then, we extend the Han-Kobayashi coding scheme to this channel. Finally, we apply these results to Gaussian channels with amplify-and-forward relaying and present numerical results showing the gain of the proposed scheme compared to the state of the art.