Distributed joint source coding and trellis coded modulation for symbol-based Markov sources

Abstract

A distributed joint source-channel coding scheme based on a unity-rate code (URC)-assisted trellis coded modulation (TCM) is proposed, which exploits the spatio-temporal correlation of symbol-based sources. More specifically, asymmetric distributed source coding of two spatially correlated Markov sources is considered, where one of the sources is assumed to be perfectly decoded and to be available at the receiver of the other source as side information. In order to exploit the temporal correlation statistics, an iterative decoding process exchanging extrinsic information between the amalgamated URC-assisted TCM and a soft-symbol source decoder employing a modified symbol-based maximum <formula><tex>$a posteriori$</tex></formula> algorithm is invoked. Furthermore, the Slepian-Wolf (SW) bound of symbol-based sources having spatio-temporal correlation is derived and the benefits of exploiting the spatio-temporal correlation using the proposed coding scheme are demonstrated by our extrinsic information transfer chart analysis. It is shown from our simulation results that upon exploiting the spatio-temporal correlation of the sources, the proposed coding scheme is capable of operating within 0.02 bit of the SW bound.