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arXiv · 2405.03348

Evolution of the 5G New Radio Two-Step Random Access towards 6G Unsourced MAC

Patrick Agostini·Jean-Francois Chamberland·Federico Clazzer·Johannes Dommel·Gianluigi Liva·Andrea Munari·Krishna Narayanan·Yury Polyanskiy·Slawomir Stanczak·Zoran Utkovski
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Abstract

This report summarizes some considerations on possible evolutions of grant-free random access in the next generation of the 3GPP wireless cellular standard. The analysis is carried out by mapping the problem to the recently-introduced unsourced multiple access channel (UMAC) setup. By doing so, the performance of existing solutions can be benchmarked with information-theoretic bounds, assessing the potential gains that can be achieved over legacy 3GPP schemes. The study focuses on the two-step random access (2SRA) protocol introduced by Release 16 of the 5G New Radio standard, investigating its applicability to support large MTC / IoT terminal populations in a grant-free fashion. The analysis shows that the existing 2SRA scheme may not succeed in providing energy-efficient support to large user populations. Modifications to the protocol are proposed that enable remarkable gains in both energy and spectral efficiency while retaining a strong resemblance to the legacy protocol.

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Patrick Agostini, Jean-Francois Chamberland, Federico Clazzer, Johannes Dommel, Gianluigi Liva, Andrea Munari, Krishna Narayanan, Yury Polyanskiy, Slawomir Stanczak, Zoran Utkovski. 2024-05-06. Evolution of the 5G New Radio Two-Step Random Access towards 6G Unsourced MAC. https://arxiv.org/abs/2405.03348

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