LDPC码的联合概率加权比特翻转译码算法  

Joint Probability of Weighted Bit-flipping Decoding Algorithm for LDPC Codes

作　　者：阮嘉程 魏东兴[1] 王伟[2] 

机构地区：[1]大连理工大学电子信息与电气工程学部 [2]中国人民解放军66440部队

出　　处：《系统仿真学报》2014年第2期306-309,352,共5页Journal of System Simulation

摘　　要：为获得低密度奇偶校验(LDPC)码译码性能和复杂度二者间的优化平衡,提出了基于比特翻转(BF)的联合概率加权比特翻转(JPWBF)译码算法。利用信道传递给变量节点的初始概率值进行硬判决并计算错误图样。统计校验关系不满足的节点,依照置信传播(BP)算法中对节点消息的处理方式更新对应节点的消息。将变量节点收集到的所有消息作为计算加权校验和的软信息,提高翻转比特位判定的可靠性。仿真结果表明:与BF类算法相比,JPWBF算法所需迭代次数少,在保持较低译码复杂度的前提下,译码性能提高1.0dB以上,是一类实用性强的LDPC码译码算法。In order to trade off the decoding performance and complexity of low-density parity-check （LDPC） codes, based on bit-flipping （BF） algorithm, joint probability of weighted bit-flipping （JPWBF） decoding algorithm was proposed. The initial probability value of channel was utilized to get hard decision and calculate the syndrome. The nodes were found out that did not satisfy the check equation and then according to node messages processing approach of belief propagation （BP） algorithm, local node messages were updated. The variable nodes collected all related messages and took these as soft information to calculate weighted check sum, which made the location of the flipped bit more reliable. The simulation results show that comparing with BF algorithm, JPWBF algorithm needs fewer iterations. Moreover, JPWBF algorithm can improve more than 1.0dB on decoding performance while maintaining a relative low decoding complexity, so it is a more practical decoding algorithm for LDPC codes.

关 键 词：低密度奇偶校验码 置信传播算法 比特翻转算法 联合译码算法 

分 类 号：TN911.3[电子电信—通信与信息系统]