计算机应用 ›› 2010, Vol. 30 ›› Issue (2): 292-294.

• 网络与通信 • 上一篇    下一篇

一种AWGN信道下非规则LDPC码的优化方法

毛倩1,董德存2,曾小清2   

  1. 1. 上海理工大学 光电学院 通信教研室
    2. 同济大学
  • 收稿日期:2009-07-29 修回日期:2009-09-21 发布日期:2010-02-10 出版日期:2010-02-01
  • 通讯作者: 毛倩
  • 基金资助:
    轨道交通运营安全的关键装备监控预警及应用技术研究

Optimization method for irregular LDPC codes in AWGN channel

  • Received:2009-07-29 Revised:2009-09-21 Online:2010-02-10 Published:2010-02-01

摘要: 提出了一种加性高斯噪声(AWGN)信道下非规则低密度奇偶校验(LDPC)码的优化方法。利用LDPC码迭代译码算法下变量节点与校验节点的EXIT曲线之间的面积反映码的收敛阈值与香农限的差距这一特点,设计表示两条EXIT曲线之间面积的函数F,该函数可以衡量非规则LDPC码的性能,F值越小,LDPC码的收敛阈值就越接近香农限。仿真显示,合理设计变量节点和校验节点,减小函数F的值,能够提高非规则LDPC码的性能。

关键词: 低密度奇偶校验码, 外部信息转换(EXIT)图, 加性高斯白噪声, 迭代译码, 收敛阈值

Abstract: A method to optimize irregular Low-Density-Parity-Check (LDPC) codes was proposed. The area gap between the EXIT curves of variable-node decoder and check-nodes decoder of a LDPC code reflects a rate loss compared to Shannon limit, a function F which computed the area gap was designed to evaluate the performance of the irregular LDPC codes. The lower the value F is, the smaller the gap between the convergence threshold and the Shannon limit is. Simulation shows that the performance of irregular LDPC codes will be improved by designing variable-node decoder and check-nodes decoder appropriately and reducing F.

Key words: Low-Density-Parity-Check (LDPC) code, EXtrinsic Information Transfer (EXIT) chart, Additive White Gaussian Noise (AWGN), iterative decoding, convergence threshold