Pseudocodeword-free criterion for codes with cycle-free Tanner graph

@article{Kositwattanarerk2018PseudocodewordfreeCF,
  title={Pseudocodeword-free criterion for codes with cycle-free Tanner graph},
  author={Wittawat Kositwattanarerk},
  journal={Designs, Codes and Cryptography},
  year={2018},
  volume={86},
  pages={2791-2805}
}
Iterative decoding and linear programming decoding are guaranteed to converge to the maximum-likelihood codeword when the underlying Tanner graph is cycle-free. Therefore, cycles are usually seen as the culprit of low-density parity-check codes. In this paper, we argue in the context of graph cover pseudocodeword that, for a code that permits a cycle-free Tanner graph, cycles have no effect on error performance as long as they are a part of redundant rows. Specifically, we characterize all… 

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