改进的Polar码的最小和译码算法  

An Improved Min-Sum Decoding Algorithm for Polar Codes

作　　者：洪银芳[1] 李晖[1] 王新梅[1] HONG Yin-fang LI Hui WANG Xin-mei(State Key Laboratory of Integrated Service Networks, Xidian University, Xi＇an 710071, China)

机构地区：[1]西安电子科技大学综合业务网理论及关键技术国家重点实验室,西安710071

出　　处：《北京邮电大学学报》2016年第6期22-26,共5页Journal of Beijing University of Posts and Telecommunications

基　　金：国家重点基础研究发展计划(973计划)项目(2012CB316100);国家自然科学基金项目(61372072)

摘　　要：提出了改进Polar码的最小和译码算法,修正了最小和译码算法中的节点更新公式,即利用分段线性函数来逼近置信度传播译码算法中的函数lncosh(x).相比于最小和译码算法,改进的算法在增加少许复杂度的情况下,增强了译码性能.相比于置信度传播译码算法,该算法在几乎不损失性能的情况下,大大降低了算法的计算复杂度,更易于硬件实现.该算法是基于最小和算法和置信度传播算法提出的,是在复杂度和性能上的一种折中.仿真结果表明,改进的最小和译码算法与置信度传播译码算法的性能几乎相同,比最小和译码算法的性能好.In order to enhance the performance of the min-sum decoding algorithm for polar codes,an improved min-sum decoding algorithm was proposed. The improved method corrects the node update formulas of the min-sum decoding algorithm which replaces the function lncosh（ x） in the belief propagation（ BP） decoding algorithm with the piecewise linear approximation functions. Compared with the min-sum decoding algorithm,the modified decoding algorithm has better performance in case of increasing a little complexity. Compared with the BP decoding algorithm,the algorithm greatly reduces the computational complexity in case of almost no performance loss,and simplifies hardware implementation. The modified algorithm is based on the min-sum and the BP algorithms,and it is a compromise between the complexity and performance. Simulations show that the performance of the improved min-sum decoding algorithm is almost the same as the BP decoding algorithm,and better than the min-sum decoding algorithm.

关 键 词：Polar码 最小和译码算法 置信度传播译码算法 分段线性函数 

分 类 号：TN911[电子电信—通信与信息系统]