极化码基于比特翻转改进的BP译码算法  

Polar Codes based on Bit Flipping Improved BP Decoding Algorithm

作　　者：王华华[1] 秦红 方泽圣 李平安 陈博 WANG Hua-hua;QIN Hong;FANG Ze-sheng;LI Ping-an;CHEN Bo(School of Communication and Information Engineering,Chongqing University of Posts and Telecommunications,Chongqing 400065,China)

机构地区：[1]重庆邮电大学通信与信息工程学院,重庆400065

出　　处：《光通信研究》2021年第4期5-9,共5页Study on Optical Communications

基　　金：国家科技重大专项资助项目(2017ZX03001021-004)。

摘　　要：极化码是世界上唯一被证明香农门限可达的编码方案。由于连续消除(SC)译码的串行特性导致时延很高,于是置信传播(BP)译码因其具有更高的吞吐量而受到了更多关注。由于BP译码性能不如SC译码,于是将比特翻转(BF)译码应用于BP中。针对当前BP BF(BPF)译码中出现的翻转集构建不准确的问题,文章提出了一种新的误码率BPF译码算法用于构建翻转集,并提出了粗翻转集和精翻转集的概念。文章通过方差能够体现数据稳定性的特点构建了粗翻转集,再通过误码率的差值大小来缩小翻转集的范围,即精翻转集。研究结果表明,文章所提算法优于目前最优的BP、增强型BPF(EBPF)和对数似然比BPF(BPF-LLR)等译码算法,同时,该算法迭代次数相比其他翻转译码算法有明显降低。Polar codes is the only coding scheme in the world that has been proved that the Shannon threshold is reachable.Because of the high time delay caused by the serial characteristic of Successive Cancellation(SC)decoding,the Belief Propagation(BP)decoding has received more attention because of its higher throughput.However,because its decoding performance is not as good as SC decoding,Bit-Flip(BF)decoding is used in BP.Aiming at the inaccurate construction of flip set in current bit flipping decoding,this paper proposes a new bit error rate BP BF(BPF)decoding algorithm,which is used to construct flip set.We also propose rough flip set and fine flip set Concept of flip set.The rough flip set is constructed by the variance of the characteristics of data stability.The range of the flip set is reduced by the difference in bit error rate,that is,the fine flip set.The research results show that the algorithm proposed in this paper is superior to the current best decoding algorithms such as BP,Enhanced BPF(EBPF)and Log Likelihood Ratio BPF(BPF-LLR).At the same time,the number of iterations of the algorithm is significantly reduced compared with other bit-flipping decoding algorithms.

关 键 词：极化码 置信传播译码 比特翻转 翻转集 

分 类 号：TN929.5[电子电信—通信与信息系统]