光通信中基于BIBD与循环矩阵分解的QC-LDPC码新颖构造方法  

A novel construction method of QC-LDPC codes for optical com munications based on the BIBD and circulant decomposition

作　　者：袁建国[1] 栗婵媛[1] 黄胜[1] 王永[1] 

机构地区：[1]重庆邮电大学光纤通信技术重点实验室,重庆400065

出　　处：《光电子．激光》2013年第9期1698-1701,共4页Journal of Optoelectronics·Laser

基　　金：国家自然科学基金(61071117;71275077;61003256);重庆市自然科学基金(2010BB2409);重庆市教委(KJ110519)资助项目

摘　　要：为了满足光通信系统中对纠错码高码率、低误码率(EBR)的要求,基于平衡不完全区组设计(BIBD)和循环矩阵分解,提出一种构造简单的新颖准循环低密度奇偶校验(QC-LDPC)码构造方法,并构造了适用于光通信系统的规则BIBDdes-QC-LDPC(6736,6316)码。仿真结果表明,在BER=10-6时其码率均为93.7%的情况下,所构造的BIBDdes-QC-LDPC(6736,6316)码的净编码增益(NCG)比已广泛应用于光通信系统中的经典RS(255,239)码改善了约2.2dB,并且比只基于BIBD所构造的同码率同码长的规则BIBD-QC-LDPC(6736,6315)和基于伽罗华域(GF)乘群所构造的同码率的非规则QC-LDPC(3843,3603)码都分别改善了约0.2dB。因而,运用本文方法构造的QC-LDPC码型的纠错性能更强,更适用于高速长距离光通信系统。并且,本文方法还具有BIBD构造方法的优点,可灵活地调整码率码长。In order to meet the requirements of the high bit-rate and the lower bit error-rate of the errorcorrection code in optical communication systems, based on the balanced incomplete block design （BIBD） and the circulant decomposition in this paper, a novel construction method of quasi-cyclic low-density parity-check （QC-LDPC） codes with the advantage of the simple implementation is proposed. A regular BIBDdes- QC- LDPC（ 6736,6316） code suitable for optical communication systems is constructed by applying the proposed method. The simulation results show that at the bit error rate （BER） of 10 6 and the same code rate of 93.7% ,the net coding gain （NCG） of the constructed BIBDdes-QC-LDPC（6736, 6316） code is 2.2 dB more than that of the classic RS（255,239） code which has been widely used in optical communication systems, and 0. 2 dB more than that of the BIBD-QC-LDPC（6736,6315） code with the same code length and the same code-rate constructed only by the BIBD method and that of the irregular QC-LDPC（3843,3603） code with the same code-rate based on Galois field multiplicative group. Therefore, the novel BIBDdes-QC-LDPC（6736,6316） code has superior error-correction performance and is more suitable for the high-speed long-haul optical communication systems. And the novel construction method still has the advantage of the BIBD method which can flexibly adjust the code length and code rate.

关 键 词：准循环低密度奇偶校验（QC—LDPC）码 平衡不完全区组设计（BIBD） 循环矩阵分解 光通信系统 

分 类 号：TN929.11[电子电信—通信与信息系统]