Joint Source-Channel Coding with Correlated Interference

TL;DR

This paper develops and compares two joint source-channel coding schemes for transmitting correlated sources over AWGN channels with interference, demonstrating improved performance and robustness under SNR variations.

Contribution

It introduces two novel joint source-channel coding schemes for correlated sources with interference, and analyzes their performance and robustness.

Findings

Both schemes outperform existing methods at perfect SNR knowledge.

They exhibit graceful performance degradation and enhancement under SNR mismatch.

Neither scheme universally outperforms the other in correlated source scenarios.

Abstract

We study the joint source-channel coding problem of transmitting a discrete-time analog source over an additive white Gaussian noise (AWGN) channel with interference known at transmitter.We consider the case when the source and the interference are correlated. We first derive an outer bound on the achievable distortion and then, we propose two joint source-channel coding schemes. The first scheme is the superposition of the uncoded signal and a digital part which is the concatenation of a Wyner-Ziv encoder and a dirty paper encoder. In the second scheme, the digital part is replaced by the hybrid digital and analog scheme proposed by Wilson et al. When the channel signal-tonoise ratio (SNR) is perfectly known at the transmitter, both proposed schemes are shown to provide identical performance which is substantially better than that of existing schemes. In the presence of an SNR mismatch, both proposed schemes are shown to be capable of graceful enhancement and graceful degradation. Interestingly, unlike the case when the source and interference are independent, neither of the two schemes outperforms the other universally. As an application of the proposed schemes, we provide both inner and outer bounds on the distortion region for the generalized cognitive radio channel.