The Mutual information of LDGM codes

Jan van den Brand; Nor Jaafari

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arXiv · 1707.04413

The Mutual information of LDGM codes

Jan van den Brand·Nor Jaafari

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Abstract

We provide matching upper and lower bounds on the mutual information in noisy reconstruction of parity check codes and thereby prove a long-standing conjecture by Montanari [IEEE Transactions on Information Theory 2005]. Besides extending a prior concentration result of Abbe and Montanari [Theory of Computing 2015] to the case of odd check degrees, we precisely determine the conjectured formula for code ensembles of arbitrary degree distribution, thus capturing a broad class of capacity approaching codes.

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Jan van den Brand, Nor Jaafari. 2017-07-14. The Mutual information of LDGM codes. https://arxiv.org/abs/1707.04413

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