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arXiv · 2210.05055

Smart Hybrid Beamforming and Pilot Assignment for 6G Cell-Free Massive MIMO

Carles Diaz-Vilor·Alexei Ashikhmin·Hong Yang
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Abstract

This paper investigates Cell-Free massive MIMO networks, where each access point (AP) is equipped with a hybrid transceiver, reducing the complexity and cost compared to a fully digital transceiver. Asymptotic approximations for the spectral efficiency are derived for uplink and downlink. Capitalizing on these expressions, a max-min problem is formulated to optimize the (i) analog beamformer at the APs and (ii) pilot assignment. Simulations show that the optimization of these variables substantially increases the network performance.

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Carles Diaz-Vilor, Alexei Ashikhmin, Hong Yang. 2022-10-11. Smart Hybrid Beamforming and Pilot Assignment for 6G Cell-Free Massive MIMO. https://arxiv.org/abs/2210.05055

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