权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Recursive Suboptimal Decoding Algorithm for Binary Linear Black Codes

二进制线性黑色码的递归次优译码算法

基本信息

批准号：
10650363
负责人：
KASAMI Tadao
金额：
$ 2.18万
依托单位：
Hiroshima City University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10650363/
关键词：
binary linear code suboptimum decoding complexity of decoding cosets weight distribution quantization level 2元線形符号

项目摘要

1. A soft-decision decoding algorithm is derived by approximating some computations in the recursive maximum likelihood decoding (RMLD) algorithm. In the RMLD algorithm, the most likely code vector is computed by constructing tables of most likely local vectors in a divide-and conquer manner. In the proposed suboptimum algorithm, vectors in the tables are pruned according to a certain criteria. The relation among the criteria of pruning, error performance and the decoding complexity is analyzed. A simulation result for the third order Reed-Muller code of length 64 shows that we can realize a suboptimum decoder which achieves almost the same error performance as an ML decoder and costs only one-fourth decoding complexity compared to the RMLD algorithm [1,2].2. The original RMLD is not adaptive to signal-to-noise (SN) ratios. In RMLD, every most likely local vectors are computed in bottom-up way. We propose a new version of RMLD which is very adaptive to SN-ratios by introducing "lazy evaluation" in a top-down way. That is, most likely local vectors are computed when it is required for the first time. These computation can be efficiently carried out by using parity check matrices of certain local subcodes of the entire code [3,4]. For several Reed-Muller codes and extended permuted BCH codes, simulation results show remarkable reduction of time and space complexity of decoding.3. The weight distribution of coset leaders of cosets with respect to a local subcode provides primary information on how to prune an insignificant subtables for most likely local vectors. A new relatively efficient algorithm for computing the weight distribution of coset leaders of binary linear block codes is proposed [5].4. The quantization levels for received sequences and the accuracy of the metric computation have effect on the probability of decoding error and the complexity of decoding circuits. A detailed case study of RMLD decoder for a (64, 35) Reed-Muller subcode has been done [6].

1.通过对递归最大似然译码（RMLD）算法中的一些计算进行近似，导出了一种软判决译码算法。在RMLD算法中，最可能的码向量是通过以分治的方式构造最可能的局部向量的表来计算的。在所提出的次优算法中，表中的向量根据一定的标准被修剪。分析了剪枝准则、误码性能和译码复杂度之间的关系。对码长为64的三阶Reed-Muller码的仿真结果表明，我们可以实现一个次优译码器，其误码性能与ML译码器几乎相同，而译码复杂度仅为RMLD算法的四分之一[1，2].原始RMLD不适应信噪比。在RMLD中，每一个最可能的本地向量计算自底向上的方式。我们提出了一个新版本的RMLD，这是非常适应SN比通过引入“懒惰的评价”在一个自上而下的方式。也就是说，最有可能的局部向量是在第一次需要时计算的。这些计算可以通过使用整个码的某些局部子码的奇偶校验矩阵来有效地进行[3，4]。对几种Reed-Muller码和扩展置换BCH码的仿真结果表明，译码的时间复杂度和空间复杂度都有显著降低.陪集的陪集领导者相对于局部子码的权重分布提供了关于如何为最可能的局部向量修剪无关紧要的子表的主要信息。提出了一种计算二元线性分组码陪集首码重量分布的新的相对有效的算法[5].接收序列的量化水平和度量计算的准确性影响译码错误的概率和译码电路的复杂度。针对（64，35）Reed-Muller子码的RMLD解码器的详细案例研究已经完成[6]。