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arXiv · 2412.14616

An Age of Information Characterization of SPS

Maria Bezmenov·Matthias Frey·Zoran Utkovski·Slawomir Stanczak
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Abstract

We derive a closed-form approximation of the stationary distribution of the Age of Information (AoI) of the semi-persistent scheduling (SPS) protocol which is a core part of NR-V2X, an important standard for vehicular communications. While prior works have studied the average AoI under similar assumptions, in this work we provide a full statistical characterization of the AoI by deriving an approximation of its probability mass function. As result, besides the average AoI, we are able to evaluate the age-violation probability, which is of particular relevance for safety-critical applications in vehicular domains, where the priority is to ensure that the AoI does not exceed a predefined threshold during system operation. The study reveals complementary behavior of the age-violation probability compared to the average AoI and highlights the role of the duration of the reservation as a key parameter in the SPS protocol. We use this to demonstrate how this crucial parameter should be tuned according to the performance requirements of the application.

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Maria Bezmenov, Matthias Frey, Zoran Utkovski, Slawomir Stanczak. 2024-12-19. An Age of Information Characterization of SPS. https://doi.org/10.1109/tvt.2026.3691247

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