Precise Analysis of Covariance Identifiability for Activity Detection in Grant-Free Random Access

Shengsong Luo; Junjie Ma; Chongbin Xu; Xin Wang

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arXiv · 2406.01138

Precise Analysis of Covariance Identifiability for Activity Detection in Grant-Free Random Access

Shengsong Luo·Junjie Ma·Chongbin Xu·Xin Wang

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Abstract

We consider the identifiability issue of maximum likelihood based activity detection in massive MIMO based grant-free random access. A prior work by Chen et al. indicates that the identifiability undergoes a phase transition for commonly-used random signatures. In this paper, we provide an analytical characterization of the boundary of the phase transition curve. Our theoretical results agree well with the numerical experiments.

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Shengsong Luo, Junjie Ma, Chongbin Xu, Xin Wang. 2024-06-03. Precise Analysis of Covariance Identifiability for Activity Detection in Grant-Free Random Access. https://arxiv.org/abs/2406.01138

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