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Open Access

Optimized Irregular Low-Density Parity-Check Codes for Multicarrier Modulations over Frequency-Selective Channels

EURASIP Journal on Advances in Signal Processing20042004:470570

Received: 1 March 2003

Published: 7 September 2004


This paper deals with optimized channel coding for OFDM transmissions (COFDM) over frequency-selective channels using irregular low-density parity-check (LDPC) codes. Firstly, we introduce a new characterization of the LDPC code irregularity called “irregularity profile.” Then, using this parameterization, we derive a new criterion based on the minimization of the transmission bit error probability to design an irregular LDPC code suited to the frequency selectivity of the channel. The optimization of this criterion is done using the Gaussian approximation technique. Simulations illustrate the good performance of our approach for different transmission channels.

Keywords and phrases

orthogonal frequency division multiplexingfrequency-selective channeloptimized channel codingirregular LDPC codesdensity evolution

Authors’ Affiliations

ETIS/ENSEA/UCP CNRS 8051, Cergy-Pontoise Cedex, France
Laboratory of Decision and Communications Systems (DéCom), University of Reims Champagne-Ardenne, UFR Sciences, Reims Cedex 2, France


© Mannoni et al. 2004