In this letter, for the first time, an edge-coloring technique is proposed to characterize a certain elementary trapping set (ETS) and to obtain sufficient conditions to avoid small ETSs from occurrence in the Tanner graph of SC-LDPC convolutional codes. This technique is applicable to all protograph-based LDPC codes with different girths whose protographs are single-edge, that is, the entries of their base matrices are 0, 1. To further demonstrate the effectiveness of our proposed technique, we apply it to Time-Invariant SC-LDPC-CCs with girths 6 and 8 and column weights up to 5.

中文翻译：

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分析空间耦合 LDPC 卷积码的基本捕获集的边缘着色技术

在这封信中，首次提出了一种边缘着色技术来表征某个基本陷阱集（ETS），并获得充分条件以避免在 SC-LDPC 卷积码的 Tanner 图中出现小 ETS。该技术适用于所有具有不同周长的基于原型的 LDPC 码，其原型是单边的，即它们的基矩阵的条目为 0, 1。为了进一步证明我们提出的技术的有效性，我们将其应用于 Time - 周长为 6 和 8 且柱重高达 5 的不变 SC-LDPC-CC。