Overlapped message passing for quasi-cyclic low-density parity check codes

Yanni Chen, Keshab K. Parhi

Research output: Contribution to journalArticlepeer-review

125 Scopus citations


In this paper, a systematic approach is proposed to develop a high throughput decoder for quasi-cyclic low-density parity check (LDPC) codes, whose parity check matrix is constructed by circularly shifted identity matrices. Based on the properties of quasi-cyclic LDPC codes, the two stages of belief propagation decoding algorithm, namely, check node update and variable node update, could be overlapped and thus the overall decoding latency is reduced. To avoid the memory access conflict, the maximum concurrency of the two stages is explored by a novel scheduling algorithm. Consequently, the decoding throughput could be increased by about twice assuming dual-port memory is available.

Original languageEnglish (US)
Pages (from-to)1106-1113
Number of pages8
JournalIEEE Transactions on Circuits and Systems I: Regular Papers
Issue number6
StatePublished - Jun 2004

Bibliographical note

Funding Information:
Manuscript received June 11, 2003; revised December 6, 2003. This work was supported by the Army Research Office under Grant DA/DAAD19-01-1-0705. This paper was presented in part at the ACM Great Lake Symposium on VLSI, April 26–29, 2003, Washington, DC. This paper was recommended by Associate Editor Y. Wang.


  • High throughput
  • Low-density parity check (LDPC) codes
  • Overlapped message passing (MP)
  • Quasi-cyclic codes


Dive into the research topics of 'Overlapped message passing for quasi-cyclic low-density parity check codes'. Together they form a unique fingerprint.

Cite this