Energy-Efficient Clustered Cell-Free Networking with Access Point Selection

Ouyang Zhou; Junyuan Wang; Fuqiang Liu; Jiangzhou Wang

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arXiv · 2403.00339

Energy-Efficient Clustered Cell-Free Networking with Access Point Selection

Ouyang Zhou·Junyuan Wang·Fuqiang Liu·Jiangzhou Wang

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Abstract

Ultra-densely deploying access points (APs) to support the increasing data traffic would significantly escalate the cell-edge problem resulting from traditional cellular networks. By removing the cell boundaries and coordinating all APs for joint transmission, the cell-edge problem can be alleviated, which in turn leads to unaffordable system complexity and channel measurement overhead. A new scalable clustered cell-free network architecture has been proposed recently, under which the large-scale network is flexibly partitioned into a set of independent subnetworks operating parallelly. In this paper, we study the energy-efficient clustered cell-free networking problem with AP selection. Specifically, we propose a user-centric ratio-fixed AP-selection based clustering (UCR-ApSel) algorithm to form subnetworks dynamically. Following this, we analyze the average energy efficiency achieved with the proposed UCR-ApSel scheme theoretically and derive an effective closed-form upper-bound. Based on the analytical upper-bound expression, the optimal AP-selection ratio that maximizes the average energy efficiency is further derived as a simple explicit function of the total number of APs and the number of subnetworks. Simulation results demonstrate the effectiveness of the derived optimal AP-selection ratio and show that the proposed UCR-ApSel algorithm with the optimal AP-selection ratio achieves around 40% higher energy efficiency than the baselines. The analysis provides important insights to the design and optimization of future ultra-dense wireless communication systems.

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BibTeX RIS

Ouyang Zhou, Junyuan Wang, Fuqiang Liu, Jiangzhou Wang. 2024-03-01. Energy-Efficient Clustered Cell-Free Networking with Access Point Selection. https://arxiv.org/abs/2403.00339

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