J4 ›› 2010, Vol. 37 ›› Issue (4): 700-704.doi: 10.3969/j.issn.1001-2400.2010.04.021

• 研究论文 • 上一篇    下一篇

一种改进的准循环LDPC码环消除算法

崔俊云;白宝明;郭旭东   

  1. (西安电子科技大学 综合业务网理论及关键技术国家重点实验室,陕西 西安  710071)
  • 收稿日期:2009-06-24 出版日期:2010-08-20 发布日期:2010-10-11
  • 作者简介:崔俊云(1984-),女,西安电子科技大学博士研究生,E-mail: 02044027@163.com.
  • 基金资助:

    国家自然科学基金资助项目(U0635003, 60532060);长江学者和创新团队发展计划资助项目(IRT0852)

Improved cycle elimination algorithm for construction of QC-LDPC codes

CUI Jun-yun;BAI Bao-ming;GUO Xu-dong   

  1. (State Key Lab. of Integrated Service Networks, Xidian Univ., Xi'an  710071, China)
  • Received:2009-06-24 Online:2010-08-20 Published:2010-10-11

摘要:

通过推广Yang, Liu 和Shi给出的从基矩阵到校验矩阵的环扩展约束条件,提出了一种大围长准循环LDPC码的构造算法.该算法改善了环消除算法的局部围长分布,获得了更好的纠错性能.仿真结果表明,在80次迭代置信传播译码下,采用本算法构造的1/2码率非规则LDPC码在Eb/N0为1.5dB时,误码率为2×10-6

关键词: 围长, 准循环LDPC码, 环消除

Abstract:

A novel construction algorithm for quasi-cyclic low-density parity-check codes is proposed, with which we can obtain the improved girth of the corresponding Tanner graph by generalizing Yang et al.'s constraint for any cycle detected in the base matrix to detect and break the cycles in the parity check matrix. Compared with the existing cycle elimination (CE) algorithm, a better error performance can be achieved and cycle-8 free. Simulation results show that the proposed algorithm for constructing the irregular LDPC code of rate 1/2 achieves the performance of codeword error rate of 2×10-6 at Eb/N0=1.5dB with 80 iterations by the belief-propagation decoding algorithm.

Key words: girth, quasi-cyclic low-density parity-check (QC-LDPC) codes, cycle elimination