Lowering the error floor of Gallager codes: a statistical-mechanical view

  title={Lowering the error floor of Gallager codes: a statistical-mechanical view},
  author={Marco Antonio M. Pretti},
  • M. Pretti
  • Published 2 July 2014
  • Computer Science, Physics, Mathematics
  • ArXiv
The error correction for Gallager's low-density parity-check codes is a problem famously equivalent to that of computing marginal Boltzmann probabilities for an Ising-like model with multispin interactions in a non-uniform magnetic field. Since the graph of interactions is locally a tree, the solution is very well approximated by a generalized mean-field (Bethe–Peierls) approximation. Belief propagation (BP) and similar iterative algorithms are an efficient method to perform the calculation… 


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