English

Low-Complexity Decoding for Low-Rate Block Codes of Short Length Based on Concatenated Coding Structure

Information Theory 2025-05-16 v1 Signal Processing math.IT

Abstract

To decode a short linear block code, ordered statics decoding (OSD) and/or the AA^* decoding are usually considered. Either OSD or the AA^* decoding utilizes the magnitudes of the received symbols to establish the most reliable and independent positions (MRIP) frame. A restricted searched space can be employed to achieve near-optimum decoding with reduced decoding complexity. For a low-rate code with large minimum distance, the restricted search space is still very huge. We propose to use concatenated coding to further restrict the search space by proposing an improved MRIP frame. The improved MRIP frame is founded according to magnitudes of log likelihood ratios (LLRs) obtained by the soft-in soft-out (SISO) decoder for the inner code. We focus on the construction and decoding of several (n,k)(n,k) = (128,36) binary linear block codes based on concatenated coding. We use the (128,36) extended BCH (eBCH) code as a benchmark for comparison. Simulation shows that there exist constructed concatenated codes which are much more efficient than the (128,36) eBCH code. Some other codes of length 128 or close to 128 are also constructed to demonstrate the efficiency of the proposed scheme.

Keywords

Cite

@article{arxiv.2505.09978,
  title  = {Low-Complexity Decoding for Low-Rate Block Codes of Short Length Based on Concatenated Coding Structure},
  author = {Mao-Chao Lin and Shih-Kai Lee and Pin Lin and Ching-Chang Lin and Chia-Chun Chen and Teng-Yuan Syu and Huang-Chang Lee},
  journal= {arXiv preprint arXiv:2505.09978},
  year   = {2025}
}
R2 v1 2026-06-28T23:33:58.639Z