IEEE Transactions on Information Theory

Average Coset Weight Distribution of Combined LDPC Matrix Ensembles

Tadashi Wadayama

Published Oct 30, 2006• 12 citations

Abstract

In this paper, the average coset weight distribution (ACWD) of structured ensembles of low-density parity-check (LDPC) matrices, which are called combined ensembles, is discussed. A combined ensemble is composed of a set of simpler ensembles such as a regular bipartite ensemble. Two classes of combined ensembles have prime importance; a stacked ensemble and a concatenated ensemble. The ACWD formulas of these ensembles are shown in this paper. Such formulas play a key role to evaluate the average weight distribution of some classes of combined ensembles

DOI: 10.1109/tit.2006.883619

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