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arXiv · 2208.03070

Activity Detection in Distributed MIMO: Distributed AMP via Likelihood Ratio Fusion

Jianan Bai·Erik G. Larsson
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Abstract

We develop a new algorithm for activity detection for grant-free multiple access in distributed multiple-input multiple-output (MIMO). The algorithm is a distributed version of the approximate message passing (AMP) based on a soft combination of likelihood ratios computed independently at multiple access points. The underpinning theoretical basis of our algorithm is a new observation that we made about the state evolution in the AMP. Specifically, with a minimum mean-square error denoiser, the state maintains a block-diagonal structure whenever the covariance matrices of the signals have such a structure. We show by numerical examples that the algorithm outperforms competing schemes from the literature.

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Jianan Bai, Erik G. Larsson. 2022-08-05. Activity Detection in Distributed MIMO: Distributed AMP via Likelihood Ratio Fusion. https://doi.org/10.1109/lwc.2022.3197053

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