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arXiv · 2605.08570

Intra-Pair Skew Propagation Graph (ISPG): An Analytical Model for Cascaded Channels

David Nozadze·Zurab Kiguradze·Srinath Penugonda·Sayed Ashraf Mamun·Amendra Koul·Mike Sapozhnikov
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Abstract

As data rates scale, intra-pair skew has become a critical bottleneck for high-speed differential signaling. Current analytical models are often limited, while 3D electromagnetic simulations are computationally intensive. This paper presents a comprehensive analytical framework for intra-pair skew in generic asymmetric coupled transmission lines, explicitly integrating skew into S-parameter formulations. We introduce the Intra-pair Skew Propagation Graph (ISPG), a novel graph-based methodology for calculating cumulative skew in complex, cascaded channels. The proposed framework is validated against both S-parameter simulations and empirical measurements of a 2m bulk twinax cable assembly, demonstrating excellent accuracy and robustness for high-speed interconnect design.

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David Nozadze, Zurab Kiguradze, Srinath Penugonda, Sayed Ashraf Mamun, Amendra Koul, Mike Sapozhnikov. 2026-05-09. Intra-Pair Skew Propagation Graph (ISPG): An Analytical Model for Cascaded Channels. https://arxiv.org/abs/2605.08570

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