奇偶校验和CRC级联的极化码编译码研究  

Parity-check and CRC aided SR-SCL encoding and decoding for polar codes

作　　者：张文宇 郭锐[1] ZHANG Wenyu;GUO Rui(School of Communication Engineering,Hangzhou Dianzi University,Hangzhou Zhejiang 310018,China)

机构地区：[1]杭州电子科技大学通信工程学院,浙江杭州310018

出　　处：《杭州电子科技大学学报（自然科学版）》2021年第6期6-12,共7页Journal of Hangzhou Dianzi University：Natural Sciences

基　　金：国家自然科学基金资助项目(U1709220)。

摘　　要：减少路径分裂次数的列表译码(Split Reduced Successive Cancellation List,SR-SCL)算法以损失部分性能为代价实现了较低的计算复杂度,增强的SR-SCL(Enhanced Split-Reduced SCL,ESR-SCL)算法在保持SR-SCL算法译码性能的同时进一步降低了复杂度。为了提升ESR-SCL算法的译码性能,提出一种奇偶校验和循环冗余校验(Cyclic Redundancy Check,CRC)辅助的ESR-SCL算法。首先,构造奇偶校验位,译码阶段根据算法提出的分裂规则进行路径分裂;然后,引入路径分裂次数相对数的概念对路径进行剪枝,运用奇偶校验比特删除校验不通过的路径;最后,结合CRC校验选取译码输出。仿真结果表明,(256,128)的极化码在误块率(Block Error Rate,BLER)为10^(-2)时,与CRC辅助的SR-SCL(CA-SR-SCL)算法相比,提出算法取得了0.21~0.25 dB的性能增益,当信噪比为1 dB时,平均列表大小减少了36.59%。A Split-Reduced-SCL(SR-SCL)algorithm can achieve lower computational complexity but unsatisfactory performance.Enhanced SR-SCL(ESR-SCL)algorithm can achieve lower computational complexity without degrading the performance of SR-SCL algorithm.In order to improve the performance of ESR-SCL,a new algorithm named parity-check and CRC aided ESR-SCL algorithm is proposed.Firstly,the parity check bits are constructed.In decoding,the relative path splitting number is defined and incorrect paths will be pruned according to the splitting rule in SR-SCL,then delete the paths not passing parity-check.Finally,one path passing the CRC detection is selected as the final output.Simulation results show that the proposed algorithm has better performance and low computational complexity at low SNR.Compared to CRC aided SR-SCL algorithm,the proposed method can get 0.21~0.25 dB performance gains for(256,128)polar code at BLER of 10^(-2).When the SNR is 1 dB,the average list size is decreased by 36.59%.

关 键 词：极化码 串行抵消列表译码 奇偶校验 路径分裂 循环冗余校验 

分 类 号：TN911.22[电子电信—通信与信息系统]