论文标题
修改后的Cole对低错误地板QC-LDPC代码构建的重要性抽样方法
An Modified Cole's Importance Sampling Method For Low Error Floor QC-LDPC Codes Construction
论文作者
论文摘要
我们修改了Cole的重要性采样（IS）方法，用于枚举陷阱集（TS，非对称子图），从而导致消息传递解码器的错误。提议的Cole是基于几种想法的组合的修改：平行TS脉冲树分解使用消息传递的迭代，这是根据Tanner Graph/ Forney的正常图形对称性的简单概念 - 图形的形态形态图。它允许上级Velasquez-Subramani和Karimi-Banihashemi Ts列举方法。与Velasquez-Subramani LP方法相比，PEG（1008，504）Mackay代码下的尤其提出的方法（1008，504）Mackay代码更快地（71463次，多束）比较速度比Velasquez-Subramani LP方法和43倍的方法比原始Cole的方法更快。对于（2640，1320）下的TS列举问题，Margulis代码与Velasquez-Subramani LP方法相比，提出的单线实现方法提出了37958次的方法，比Karimi-Banihashemi快37958次，比CoLE的原始方法快134次。 NVIDIA TITAN RTX GPU的实施提出的方法进一步加速了2-30倍。 FPGA设备可提供1.25次至44次进一步加速。我们以QC-LDPC代码的示例显示了EMD频谱的改进，增加锤（代码）距离对TS频谱和BER/FER/FER/FER误差层水平的效果。
We modified Cole's Importance Sampling (IS) method for enumerating of Trapping Sets (TS, asymmetric subgraphs) causing an error under message-passing decoder. Proposed Cole's IS modifications based on combination of several ideas: parallel TS impulse tree decomposition using unwrapping of message passing iterations, according short cycles dense and straightforward idea of Tanner Graph/ Forney's Normal Graph symmetry - Graph Authomorphism. Its allowed superior Velasquez-Subramani and Karimi-Banihashemi TS enumerating methods. Particularly proposed method under PEG (1008, 504) Mackay code for single thread implementation 5027-times (71463 times, multi-treads) faster compare to Velasquez-Subramani LP method and 43-times faster compare to original Cole's method. For TS enumerating problem under (2640, 1320) Margulis code compare to Velasquez-Subramani LP method proposed method for single thread implementation 37958 times faster, 82-times faster than Karimi-Banihashemi and 134-times faster than Cole's original method. NVIDIA Titan RTX GPU implementation of proposed method gives a further 2-30 times acceleration. FPGA device providing further acceleration from 1.25 to 44 times. We show on example of QC-LDPC codes construction how improvement of EMD spectrum, increase hamming(code) distance effect on TS spectrum and BER/FER error-floor level.
