逼近最小和译码性能的并行多比特翻转译码算法研究

Parallel Multi-Bit Flipping Decoding with Near Min-Sum Decoding Performance

相比于最小和译码算法,LDPC码的另外一种译码算法——比特翻转译码算法实现更简单,但其性能有较大恶化。最近提出的有噪梯度下降比特翻转译码(NGDBF)算法性能相比简单的比特翻转算法性能有明显提高,但该算法一次翻转一个比特限制了其应用。结合并行加权比特翻转译码(PWBF)中翻转标记的思想,本文提出了一种NGDBF译码的改进算法——并行NGDBF译码及其自适应形式,克服了PWBF译码对行重/列重较小的LDPC码性能不佳的缺陷。仿真表明:并行NGDBF译码的性能优于相应的NGDBF译码,其自适应形式不仅性能逼近最小和译码,而且实现简单。

Compared to min-sum algorithm,bit-flipping algorithm for decoding of low-density parity-check（ LDPC） codes can be implemented with lower complexity,but perform worse. There are increased interests on improving the performance of bit-flipping algorithm without much increase of complexity,and a recent progress is the development of the noisy gradient descent bit-flip（ NGDBF） algorithm. In this paper,we propose a parallel version of NGDBF（ P-NGDBF） algorithm by borrowing some ideas from parallel weighted bit-flipping（ PWBF） decoding,which shows its performance favor for low row /column weight LDPC matrices. Simulations shows that the P-NGDBF algorithm has better decoding performance and its adaptive version can perform very close to the min-sum algorithm.