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arXiv · 2002.00670

Learning-based Max-Min Fair Hybrid Precoding for mmWave Multicasting

Luis F. Abanto-Leon·Gek Hong·Sim
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Abstract

This paper investigates the joint design of hybrid transmit precoder and analog receive combiners for single-group multicasting in millimeter-wave systems. We propose LB-GDM, a low-complexity learning-based approach that leverages gradient descent with momentum and alternating optimization to design (i) the digital and analog constituents of a hybrid transmitter and (ii) the analog combiners of each receiver. In addition, we also extend our proposed approach to design fully-digital precoders. We show through numerical evaluation that, implementing LB-GDM in either hybrid or digital precoders attain superlative performance compared to competing designs based on semidefinite relaxation. Specifically, in terms of minimum signal-to-noise ratio, we report a remarkable improvement with gains of up to 105% and 101% for the fully-digital and hybrid precoders, respectively.

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Luis F. Abanto-Leon, Gek Hong, Sim. 2020-02-03. Learning-based Max-Min Fair Hybrid Precoding for mmWave Multicasting. https://arxiv.org/abs/2002.00670

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