English

Spatially Coupled LDPC Codes with Sub-Block Locality

Information Theory 2020-09-29 v2 math.IT

Abstract

A new type of spatially coupled low-density parity-check (SC-LDPC) codes motivated by practical storage applications is presented. SC-LDPCL codes (suffix 'L' stands for locality) can be decoded locally at the level of sub-blocks that are much smaller than the full code block, thus offering flexible access to the coded information alongside the strong reliability of the global full-block decoding. Toward that, we propose constructions of SC-LDPCL codes that allow controlling the trade-off between local and global correction performance. In addition to local and global decoding, the paper develops a density-evolution analysis for a decoding mode we call semi-global decoding, in which the decoder has access to the requested sub-block plus a prescribed number of sub-blocks around it. SC-LDPCL codes are also studied under a channel model with variability across sub-blocks, for which decoding-performance lower bounds are derived.

Keywords

Cite

@article{arxiv.1910.12217,
  title  = {Spatially Coupled LDPC Codes with Sub-Block Locality},
  author = {Eshed Ram and Yuval Cassuto},
  journal= {arXiv preprint arXiv:1910.12217},
  year   = {2020}
}
R2 v1 2026-06-23T11:56:07.368Z