Publications-Detail

On Joint Source-Channel Decoding for Correlated Sources

Authors:
Adrat, M. ,  Haenel, R. ,  Vary, P.
Book Title:
Proceedings of IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP)
Volume:
3
Pages:
p.p. 2505 - 2508
Address:
Orlando, Florida, USA
Date:
May. 2002
Language:
English

Abstract

Whenever digital communications is subject to constraints in delay and complexity, some residual redundancy remains after source coding. Shannon's separation theorem does not hold strictly and hence joint source-channel decoding is beneficial. We discuss two competing approaches exploiting residual redundancy in terms of (auto)-correlation. Both are analyzed with respect to their impact on quantization noise and channel distortion. The first approach exploits redundancy at the receiver for minimum mean squared error estimation of source codec parameters. The second approach exploits correlation at the transmitter by predictive encoding. The prediction gain allows one to reduce quantization noise or bit rate. The spare bit rate can be used for specific error protection and hence reduction of channel distortion. But otherwise, less redundancy is utilizable at the receiver for parameter estimation. Simulations show that the predictive encoding scheme improves quality in a wide range of channel conditions, but in contrast to Shannon's separation theorem the utilization of correlation at the receiver side is beneficial in very bad channel conditions.

Download

BibTeX

Copyright © by IKS
adrat02.pdf
This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder.