光通信中基于有限域加群的一种QC-LDPC码  

A novel construction method of the QC-LDPC code based on finite field additive group for optical communications

作　　者：袁建国[1] 刘文龙[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1期75-78,共4页Journal of Optoelectronics·Laser

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

摘　　要：针对光通信系统传输特性要求的日益提高,基于有限域GF(q)加群提出了一种构造简单且适合光通信系统的新颖准循环低密度奇偶校验(QC-LDPC)码构造方法,该构造方法可灵活的调整码长、码率且其编译码复杂度低。用此方法构造了适用于光通信系统的规则QC-LDPC(4599,4307)码。仿真结果表明,在BER=10-7时且码率均为93.7%的情况下,所构造的QC-LDPC(4599,4307)码的净编码器增益(NCG)比已广泛应用于光通信系统中的经典RS(255,239)码提高了约2.2dB,比用SCG构造方法构造的SCG-LDPC(3969,3720)码和非规则的QC-LDPC(3843,3603)码的NCG分别提高了约0.47dB和0.25dB,距离香农限约1dB。因而其纠错性能更强,更适用于高速长距离光通信系统。Based on finite field （GF（q）） additive group,a novel construction method with the advantages of simple construction and easy implementation of quasi-cyclic low-density parity-check （QC-LDPC） codes for optical communication systems is proposed in order to meet the increasing requirement on the transmission characteristics. The novel construction method can flexibly adjust the code-length and coderate, and furthermore, the complexity of the encoding and decoding in lower. A regular QC-LDPC （4599, 4307） code to be suitable for optical communication systems is constructed by applying the proposed method. The simulation results show that at the condition of the bit error rate （BER） of 10 7 and the same code rate of 93.7% ,the net coding gain （NCG） of the constructed QC-LDPC （4599,4307） code is 2.2 dB more than that of the classic RS （255,239） code which has widely been applied iin optical communication systems,and 0. 47 dB and 0.25 dB more than those of the SCG-LDPC （39G9,3720） code constructed by the systematically constructed gallager （SCG） construction method and the irregular QC- LDPC （3843,3603） code respectively, and is 1 dB away from the Shannon limit. Therefore, the novel QC-LDPC （4599,4307） code has superior error-correction performance and is more suitable for the high-speed long-haul optical communication systems.

关 键 词：准循环低密度奇偶校验(QC—LDPC)码 有限域 净编码增益(NCG) 光通信系统 

分 类 号：TN929.11[电子电信—通信与信息系统]