The belief propagation (BP) decoding of short low-density parity check codes suffers from short cycles and trapping sets. A number of perturbation schemes have been proposed to overcome the limitation. This letter presents a generalized framework for multi-round BP decoding with input perturbation and proposes an improved perturbation scheme. In particular, the impulsive perturbation which is applied to only a few symbols is proposed, along with a new space selection criterion. The proposed scheme performs better than existing schemes for short codes at lower complexity and supports a parallel implementation.

中文翻译：

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短LDPC码脉冲扰动多轮置信度传播解码

短低密度奇偶校验码的置信传播 (BP) 解码受到短周期和陷阱集的影响。已经提出了许多扰动方案来克服该限制。这封信提出了具有输入扰动的多轮BP解码的通用框架，并提出了改进的扰动方案。特别是，提出了仅应用于少数符号的脉冲扰动以及新的空间选择标准。所提出的方案以较低的复杂度比现有的短代码方案性能更好，并支持并行实现。