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arXiv:cs/0605069 · Physica A Statistical Mechanics and its Applications

Parallel vs. sequential belief propagation decoding of LDPC codes over and Markov sources

Nadav Yacov, Hadar Efraim, Haggai Kfir, Ido Kanter, Ori Shental

Published Jan 15, 2007• 6 citations
arXivHTMLPDF
DOI
10.1016/j.physa.2006.12.009

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The design of LDPC decoders with low complexity, high throughput, and good performance is a critical task. A well-known strategy is to design structured codes such as quasi- cyclic LDPC (QC-LDPC) that allow partially-parallel decoders. Sequential schedules, such as Layered Belief-Propagation (LBP), converge faster than the traditional flooding schedule while allowing parallel decoding of QC-LDPC codes. In this paper, we propose a novel low-complexity sequential schedule called Zigzag LBP (Z-LBP). Current LBP schedules do not allow partially- parallel architectures in the regime of high-rate codes with small- to-medium blocklengths. Our proposed algorithm can still be implemented in a partially-parallel manner in this regime. Z-LBP provides the same benefits as LBP including faster convergence speed and lower frame error rates than flooding.
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