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arXiv · 2006.07750

Uplink Power Control in Cellular Massive MIMO Systems: Coping With the Congestion Issue

Trinh Van Chien·Emil Björnson·Hien Quoc Ngo
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Abstract

One main goal of 5G-and-beyond systems is to simultaneously serve many users, each having a requested spectral efficiency (SE), in an energy-efficient way. The network capacity cannot always satisfy all the SE requirements, for example, when some users have bad channel conditions, especially happening in a cellular topology, and therefore congestion can happen. By considering both the pilot and data powers in the uplink transmission as optimization variables, this paper formulates and solves an energy-efficiency problem for cellular Massive MIMO (Multiple Input Multiple Output) systems that can handle the congestion issue. New algorithms based on the alternating optimization approach are proposed to obtain a fixed-point solution. Numerical results manifest that the proposed algorithms can provide the demanded SEs to many users even when the congestion happens.

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Trinh Van Chien, Emil Björnson, Hien Quoc Ngo. 2020-06-14. Uplink Power Control in Cellular Massive MIMO Systems: Coping With the Congestion Issue. https://arxiv.org/abs/2006.07750

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