IEEE Communications Letters

On the minimum pseudo-codewords of LDPC codes

Shu-Tao Xia, Fang‐Wei Fu

Published May 1, 2006• 10 citations

Abstract

In this letter, we study the minimum pseudo-codewords of low-density parity-check (LDPC) codes under linear programming (LP) decoding. We show that a lower bound of Chaichanavong and Siegel on the pseudo-weight of a pseudo-codeword is tight if and only if this pseudo-codeword is a real multiple of a codeword. Using this result we further show that for some LDPC codes, e.g., Euclidean plane and projective plane LDPC codes, there are no other minimum pseudo-codewords except the real multiples of minimum codewords.

DOI: 10.1109/lcomm.2006.1633324

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