Zero-Delay Joint Source-Channel Coding for a Bivariate Gaussian on a Gaussian MAC

TL;DR

This paper introduces two low-delay, low-complexity joint source-channel coding schemes for transmitting correlated Gaussian sources over a Gaussian MAC, demonstrating robustness and near-optimal performance at high SNR.

Contribution

It proposes two novel distributed JSCC schemes—one discrete and one hybrid—that outperform existing methods in correlated Gaussian source transmission over GMAC.

Findings

Performance improves with higher source correlation

Schemes are robust against noise variations

Achieve a constant gap to the upper bound at high SNR

Abstract

In this paper, delay-free, low complexity, joint source-channel coding (JSCC) for transmission of two correlated Gaussian memoryless sources over a Gaussian Multiple Access Channel (GMAC) is considered. The main contributions of the paper are two distributed JSCC schemes: one discrete scheme based on nested scalar quantization, and one hybrid discrete-analog scheme based on a scalar quantizer and a linear continuous mapping. The proposed schemes show promising performance which improve with increasing correlation and are robust against variations in noise level. Both schemes exhibit a constant gap to the performance upper bound when the channel signal-to-noise ratio gets large.