Achievable Rates and Upper bounds for the Interference Relay Channel

TL;DR

This paper derives new upper bounds and proposes a transmission strategy for the Gaussian interference channel with a full-duplex relay, advancing understanding of achievable rates in this communication setup.

Contribution

It introduces tighter upper bounds and a novel transmit strategy combining multiple coding techniques for the interference relay channel.

Findings

New upper bounds are tighter than previous bounds under certain conditions.

The proposed scheme achieves rates within a finite gap of the upper bounds.

The strategy effectively combines Block Markov encoding, Han-Kobayashi scheme, decode-and-forward, and backward decoding.

Abstract

The two user Gaussian interference channel with a full-duplex relay is studied. By using genie aided approaches, two new upper bounds on the achievable sum-rate in this setup are derived. These upper bounds are shown to be tighter than previously known bounds under some conditions. Moreover, a transmit strategy for this setup is proposed. This strategy utilizes the following elements: Block Markov encoding combined with a Han-Kobayashi scheme at the sources, decode and forward at the relay, and Willems' backward decoding at the receivers. This scheme is shown to achieve within a finite gap our upper bounds in certain cases.