This letter presents a construction flow for rate-compatible LDPC (RC-LDPC) codes, collaboratively using both extension and splitting schemes. In addition to the decoding threshold used for selecting the degree distribution, a new metric, known as the Average ACE ( $A^{2}CE$ ) value, is introduced in order to estimate the Tanner graph connectivity. The proposed collaborative scheme provides more flexibility in the designs of the degree distribution and graph connectivity, both of which are critical for RC LDPC codes that have short and/or moderate lengths. The designed LDPC codes achieve a comparable or better error rate performance compared to existing codes.

中文翻译：

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一种同时使用扩展和分裂的协同RC QC-LDPC码构建方案

这封信展示了速率兼容的 LDPC (RC-LDPC) 码的构建流程，协同使用扩展和拆分方案。除了用于选择度分布的解码阈值外，还引入了一个新的度量，称为平均 ACE ( $A^{2}CE$ ) 值，以估计 Tanner 图的连通性。所提出的协作方案在度分布和图连通性的设计中提供了更大的灵活性，这两者对于具有短和/或中等长度的 RC LDPC 代码至关重要。与现有代码相比，设计的 LDPC 代码实现了可比或更好的错误率性能。