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arXiv · 2504.19954

Type-Based Unsourced Multiple Access over Fading Channels with Cell-Free Massive MIMO

Kaan Okumus·Khac-Hoang Ngo·Giuseppe Durisi·Erik G. Ström
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Abstract

Type-based unsourced multiple access (TUMA) is a recently proposed framework for type-based estimation in massive uncoordinated access networks. We extend the existing design of TUMA, developed for an additive white Gaussian channel, to a more realistic environment with fading and multiple antennas. Specifically, we consider a cell-free massive multiple-input multiple-output system and exploit spatial diversity to estimate the set of transmitted messages and the number of users transmitting each message. Our solution relies on a location-based codeword partition and on the use at the receiver of a multisource approximate message passing algorithm in both centralized and distributed implementations. The proposed TUMA framework results in a robust and scalable architecture for massive machine-type communications.

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Kaan Okumus, Khac-Hoang Ngo, Giuseppe Durisi, Erik G. Ström. 2025-04-28. Type-Based Unsourced Multiple Access over Fading Channels with Cell-Free Massive MIMO. https://arxiv.org/abs/2504.19954

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