IEEE International Symposium on Information Theory (ISIT)

EBP-GEXIT Charts Over the Binary-Input AWGN Channel for Generalized and Doubly-Generalized LDPC Codes

Arti D. Yardi, Iryna Andriyanova, Charly Poulliat

Published Jun 1, 2018• 4 citations

Abstract

This work proposes a tractable evaluation of the maximum a posteriori (MAP) threshold of sparse-graph ensembles, by using an approximation for the extended belief propagation generalized extrinsic information transfer (EBP-GEXIT) function, first proposed by Measson et al. The approximation allows to find a MAP threshold in such numerically involved cases as the binary-input additive white Gaussian noise (AWGN) channel, graph ensembles with general component codes and/or irregularities. The paper contains examples of estimations of the MAP thresholds in the case of irregular low-density parity-check (LDPC), generalized LDPC, and doubly generalized LDPC codes ensembles. Our estimations are confirmed by numerical simulations.

DOI: 10.1109/isit.2018.8437727

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