Soft-decision Multi-stage Decoding for Linear Block Codes

线性分组码的软判决多级译码

• 批准号: 08650429
• 负责人: KASAMI Tadao
• 金额: $ 1.28万
• 依托单位: NARA Institute of Science and Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08650429/
• 关键词: multistage decoding; soft-decision; suboprimum decoding; linear block codes; error performance; decoding complexity; closest-coset decoding; 最大先験確率法; トレリスダイアグラム; 再帰的最尤復号法

The purpose of this research project is to improve the error performances of multistage decoding schemes by using soft-values between consecutive component decoders. For this sake, the authors have developed n efficient soft-in/soft-out log-MAP recursive decoding algorithm (R-logMap algorithm). The algorithm makes use of the structural properties of linear block codes, and reduces the decoding complexity significantly compared to the conventional BCJR algorithm. For example, computer simulation showed that the complexity of the proposed algorithm necessary for decoding of the second-order Reed-Muller (RM) code of length 128 is only 3% of that of the conventional BCJR algorithm, where the complexity is measured by the number of addition-equivalent operations of metrics. The log-MAP decoding uses some approximations in decoding process to reduce computational complexity and therefore its performance is not as good as the optimal MAP decoding. By modifying the R-logMAP algorithm slightly, … More an efficient MAP algorithm can be realized easily. By using the proposed log-MAP and MAP algorithms, the total decoding complexity of the proposed multistage decoding scheme can be reduced significantly. Among multistage decoding schemes, the authors have investigated closest-coset decoding schemes in details. A new multistage iterative decoding scheme can be realized by replacing component decoders of the closest-coset decoder with log-MAP or MAP decpder and introducing a feedback from the last stage to the first stage. The decoding complexity and the error performance of the new scheme are evaluated. Simulation results show that, for the decoding of the second-order RM code of length 64, the proposed scheme with log-MAP (res.MAP) decoding with two (resp.five) repetition improves the performance by 0.4dB (resp.0.5sB) at 10^<-5> block error rate, compared to the conventional closest-coset decoding scheme. The error performance degraduation from the maximum likelihood (ML) decoder is 0.6dB (resp.0.5dB), but the proposed schemes have significantly smaller complexity than the ML decoder. For example, the complexity necessary for the proposed scheme with log-MAP decoding is only one fifth of that of the ML decoder. Less

本研究项目的目的是利用连续分量译码之间的软值来改善多级译码方案的误码性能。为此，作者提出了n种高效的软输入/软输出LOG-MAP递归译码算法(R-LogMap算法)。该算法利用了线性分组码的结构特性，与传统的BCJR译码算法相比，译码复杂度显著降低。例如，计算机仿真表明，对于长度为128的二阶Reed-Muller(RM)码，该算法的译码复杂度仅为传统BCJR算法的3%，而BCJR算法的复杂度由度量的加法等价运算次数来衡量。LOG-MAP译码在译码过程中使用了一些近似来降低计算复杂度，因此其性能不如最优MAP译码。通过对R-logMAP算法稍作修改，…更有效的MAP算法更容易实现。通过使用所提出的LOG-MAP和MAP算法，可以显著降低所提出的多级译码方案的总译码复杂度。在多级译码方案中，作者对最近陪集译码方案进行了详细的研究。通过将最接近陪集译码的分量译码替换为LOG-MAP或MAP译码，并在最后一级向第一级引入反馈，可以实现一种新的多级迭代译码方案。对新方案的译码复杂度和误码性能进行了评估。仿真结果表明，对于长度为的二阶RM码的译码，该译码方案与传统的最接近陪集译码方案相比，在误块率为10^~(-5)的情况下，译码性能比传统的最接近陪集译码方案提高了0.4dB(分别为0.5sB)。与最大似然(ML)译码相比，最大似然(ML)译码的误码性能下降了0.6dB(分别为0.5db)，但所提出的译码方案的复杂度明显低于ML译码。例如，所提出的Log-MAP译码方案所需的复杂度仅为ML译码的五分之一。较少

项目成果

S.Lin, T.Fujiwara, H.Yamamoto and T.Kasami: ""A recursive Maximum-Likelihood Decoding Algorithm for Binary Linear Block Codes"" Globecom'97,Communication Theory Mini-Conference,Phoenix,AZ. 37 (1997)

S.Lin、T.Fujiwara、H.Yamamoto 和 T.Kasami：“二进制线性分组码的递归最大似然解码算法”Globecom97，通信理论小型会议，凤凰城，亚利桑那州。

S.Lin, T.Fujiwara, H.Yamamoto and T.Kasami: "A recursive Maximum-Likelihood Decoding Algorithm for Binary Linear Block Codes" Globecom '97 Communication Theory Mini-Conference, Phoenix, AZ. 37 (1997)

S.Lin、T.Fujiwara、H.Yamamoto 和 T.Kasami：“二进制线性分组码的递归最大似然解码算法”Globecom 97 通信理论小型会议，亚利桑那州菲尼克斯。

Y.Kaji, and T.Kasami: "Multistage Decoding Algorithm Which Uses Soft-Values between Consecutive Stages" The Twentieth Symposium on Information Thoery and Its Applications. 329-332 (1997)

Y.Kaji和T.Kasami：“在连续阶段之间使用软值的多阶段解码算法”第二十届信息论及其应用研讨会。

T.Fujiwara, T.Komura, T.Onoye, Y.Kaji, T.Kasami and S.Lin: "IC Implementation of a Recursive Maximum Likelihood Decoding Algorithm for Reed-Muller and Related Codes" The 4th International Symposium on the Communicaiton Theory and Applications,The Lake Dis

T.Fujiwara、T.Komura、T.Onoye、Y.Kaji、T.Kasami 和 S.Lin：“Reed-Muller 及相关代码的递归最大似然解码算法的 IC 实现”第四届通信理论国际研讨会

T.Fujiwara, H.Yamamoto, T.Kasami and S.Lin: "A Trellis Based Recursive Maximum Likelihood Decoding Algorithm for Linear Block Codes (to appear)" IEEE Trans.on Information Theory. Vol.44,No.2. (1998)

T.Fujiwara、H.Yamamoto、T.Kasami 和 S.Lin：“线性分组码的基于网格的递归最大似然解码算法（即将出现）”IEEE Trans.on 信息理论。