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arXiv · 1004.5217

Analysis of Quasi-Cyclic LDPC codes under ML decoding over the erasure channel

Mathieu Cunche·Valentin Savin·Vincent Roca
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Abstract

In this paper, we show that Quasi-Cyclic LDPC codes can efficiently accommodate the hybrid iterative/ML decoding over the binary erasure channel. We demonstrate that the quasi-cyclic structure of the parity-check matrix can be advantageously used in order to significantly reduce the complexity of the ML decoding. This is achieved by a simple row/column permutation that transforms a QC matrix into a pseudo-band form. Based on this approach, we propose a class of QC-LDPC codes with almost ideal error correction performance under the ML decoding, while the required number of row/symbol operations scales as $k\sqrt{k}$, where $k$ is the number of source symbols.

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Mathieu Cunche, Valentin Savin, Vincent Roca. 2010-04-29. Analysis of Quasi-Cyclic LDPC codes under ML decoding over the erasure channel. https://arxiv.org/abs/1004.5217

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