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arXiv · 1103.2837

Reweighted LP Decoding for LDPC Codes

Amin Khajehnejad·Alexandros G. Dimakis·Babak Hassibi·Benjamin Vigoda·William Bradley
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Abstract

We introduce a novel algorithm for decoding binary linear codes by linear programming. We build on the LP decoding algorithm of Feldman et al. and introduce a post-processing step that solves a second linear program that reweights the objective function based on the outcome of the original LP decoder output. Our analysis shows that for some LDPC ensembles we can improve the provable threshold guarantees compared to standard LP decoding. We also show significant empirical performance gains for the reweighted LP decoding algorithm with very small additional computational complexity.

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Amin Khajehnejad, Alexandros G. Dimakis, Babak Hassibi, Benjamin Vigoda, William Bradley. 2011-03-15. Reweighted LP Decoding for LDPC Codes. https://arxiv.org/abs/1103.2837

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