基于关键简化集合的极化码SSRFSC翻转译码算法

SSRFSC flipping decoding algorithm based on critical simplification set for polar codes

为提高基于简化序列重复节点的快速串行抵消(SSRFSC)译码算法的译码性能,提出了基于关键简化集合(CSS)和简化序列重复(SSR)节点的CSS-SSR-Flip译码算法。所提算法首先选取SSR中最长重复(REP)节点的信息位作为候选比特(CB),从而构造了基于SSR的CSS;然后针对SSR节点的译码特点设计了相应的翻转度量和翻转准则,通过考虑SSR节点中重复序列和源节点对译码的影响来度量CB可靠性,在特定CB翻转时选择次优的重复序列完成SSR节点翻转操作。实验数据表明,当误帧率FER=10-3时,所提出的CSSSSR-Flip译码算法与传统的快速简化串行抵消翻转(Fast-SSC-Flip)译码算法相比能够获得超过0.1 dB的性能增益,且具有与新型Fast-SSC-Flip(New-Fast-SSC-Flip)译码算法相同的译码性能;与传统翻转集合大小K相比,CSS大小缩减最多达79.5%,与关键集合(CS)相比集合大小最多可缩减23.1%。

To improve the decoding performance of the simplified sequence repetition node-based fast successive cancellation(SSRFSC)decoding algorithm,a decoding algorithm(CSS-SSR-Flip)based on critical simplified set(CSS)and simplified sequence repetition(SSR)nodes was designed.Firstly,the information bit of the longest repetition(REP)node in SSR was selected as candidate bit(CB),thus constructing a CSS based on SSR.Corresponding flip metrics and flip criterion were designed according to the decoding characteristics of SSR nodes.Secondly,the CB reliability was measured by considering the influence of repetition sequences and the source of SSR nodes on decoding,and suboptimal repetition sequences were selected to complete SSR node flip operations during specific CB flips.Experimental data shows that at frame error rates of 10-3,CSS-SSR-Flip decoding algorithm is able to obtain more than 0.1 dB performance gain compared to the traditional fast simplified successive cancellation filp(Fast-SSC-Flip)decoding algorithm,and has the same decoding performance as the new Fast-SSC-Flip(New-Fast-SSC-Flip)decoding algorithm.However,compared to the traditional flip set size K,the CSS size of the proposed algorithm is reduced by up to 79.5%,and compared to the critical set(CS),the set size can be reduced by up to 23.1%.