Tsinghua Science & Technology

Multistep linear programming approaches for decoding low-density parity-check codes

Haiyang Liu, Lianrong Ma, Jie Chen

Published Oct 1, 2009• 2 citations

Abstract

The problem of improving the performance of linear programming (LP) decoding of low-density parity-check (LDPC) codes is considered in this paper. A multistep linear programming (MLP) algorithm was developed for decoding LDPC codes that includes a slight increase in computational complexity. The MLP decoder adaptively adds new constraints which are compatible with a selected check node to refine the results when an error is reported by the original LP decoder. The MLP decoder result is shown to have the maximum-likelihood (ML) certificate property. Simulations with moderate block length LOpe codes suggest that the M LP decoder gives better performance than both the original LP decoder and the conventional sum-product (SP) decoder.

DOI: 10.1016/s1007-0214(09)70117-8

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