Lossy Source Transmission over the Relay Channel

TL;DR

This paper investigates lossy source transmission over relay channels with correlated side information, proposing new cooperation schemes that significantly improve reconstruction quality and approach theoretical lower bounds.

Contribution

It introduces a joint source-channel decode-and-forward scheme for general sources and channels, and analyzes new cooperation strategies for Gaussian relay channels.

Findings

Joint source-channel cooperation improves reconstruction quality.

Proposed schemes perform close to the lower bound on distortion.

Analysis shows significant gains over traditional methods.

Abstract

Lossy transmission over a relay channel in which the relay has access to correlated side information is considered. First, a joint source-channel decode-and-forward scheme is proposed for general discrete memoryless sources and channels. Then the Gaussian relay channel where the source and the side information are jointly Gaussian is analyzed. For this Gaussian model, several new source-channel cooperation schemes are introduced and analyzed in terms of the squared-error distortion at the destination. A comparison of the proposed upper bounds with the cut-set lower bound is given, and it is seen that joint source-channel cooperation improves the reconstruction quality significantly. Moreover, the performance of the joint code is close to the lower bound on distortion for a wide range of source and channel parameters.