Structured LDPC codes over GF(2m) and companion matrix based decoding

Vidya Kumar, Olgica Milenkovic, Bane Vasic

Research output: Contribution to journalConference articlepeer-review

5 Scopus citations


It is well known that random-like low-density parity-check (LDPC) codes over the extension fields GF(2m) of GF(2), for m > 1, tend to outperform their binary counterparts of comparable length and rate [1]. At the same time, structured LDPC codes offer the advantage of reduced implementation and storage complexity, so that it is of interest to investigate mathematical design methods for codes on graphs over fields of large order. In this paper, we propose a new class of combinatorially developed codes obtained by properly combining Reed-Solomon (RS) type parity-check matrices and sparse parity-check matrices based on permutation matrices. The proposed codes have large girth and minimum distance. In order to further reduce the decoding complexity of the proposed scheme, we introduce a new decoding algorithm based on matrix representations of the underlying field, which trades performance for complexity. The particular field representation described in this abstract is based on a power basis generated by a companion matrix of a primitive polynomial of the field GF(2m). It is observed that the choice of the primitive polynomial influences the cycle distribution of the code graph.

Original languageEnglish (US)
Pages (from-to)273
Number of pages1
JournalIEEE International Symposium on Information Theory - Proceedings
StatePublished - 2004
EventProceedings - 2004 IEEE International Symposium on Information Theory - Chicago, IL, United States
Duration: Jun 27 2004Jul 2 2004

ASJC Scopus subject areas

  • Theoretical Computer Science
  • Information Systems
  • Modeling and Simulation
  • Applied Mathematics


Dive into the research topics of 'Structured LDPC codes over GF(2m) and companion matrix based decoding'. Together they form a unique fingerprint.

Cite this