Open Access

Enhancement of Unequal Error Protection Properties of LDPC Codes

EURASIP Journal on Wireless Communications and Networking20072007:092659

DOI: 10.1155/2007/92659

Received: 13 March 2007

Accepted: 2 October 2007

Published: 2 December 2007


It has been widely recognized in the literature that irregular low-density parity-check (LDPC) codes exhibit naturally an unequal error protection (UEP) behavior. In this paper, we propose a general method to emphasize and control the UEP properties of LDPC codes. The method is based on a hierarchical optimization of the bit node irregularity profile for each sensitivity class within the codeword by maximizing the average bit node degree while guaranteeing a minimum degree as high as possible. We show that this optimization strategy is efficient, since the codes that we optimize show better UEP capabilities than the codes optimized for the additive white Gaussian noise channel.


Authors’ Affiliations

ETIS laboratory, UMR 8051-ENSEA/UCP/CNRS


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© Charly Poulliat et al. 2007

This article is published under license to BioMed Central Ltd. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.