并行级联分组码的一种新的迭代译码算法

并行级联分组码比串行级联分组码具有更高的码率，基于LLR计算的Turbo迭代译码算法使其内外分量码均做到了软判决译码。通过引入校正因子a（m），将接收信息与子译码器的输出软信息进行线性叠加反馈能在省去繁琐的LLR计算的情况下实现并行级联分组码的Turbo迭代译码。仿真研究表明，若将译码器的输出进行简单的相关运算，可进一步改善译码器性能。

A New Iterative Decoding Algorithm of Parallel Concatenated Block Code

Both parallel and serial concatenated block code can be decoded by turbo iterative decoding based on LLR, the code rate of the former is higher than that of the latter, and its inside and outside component codes can both do soft decision decoding with the turbo iterative decoding algorithm. In this paper, a adjustment factor a（m） is introduced to define the linear superposition feedback, and the computation amount of the algorithm is greatly decreased by using simple correlation operation in stead of the complicated LLR operation in the conventional product iterative decoding. The simulation has proved its effectiveness.