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arXiv · 2610.17478

Energy-Efficient RF Chain Activation for Uplink mmWave Cell-Free Massive MIMO Systems: A Minimum-Cost Maximum-Flow Approach

Bo Yu·Abdol Hamid Aghvami·Mohammad Shikh-Bahaei
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Abstract

With the incessant demand for green and sustainable communications, energy efficiency (EE) has become a cornerstone of sixth-generation (6G) network design, especially for cell-free millimeter-wave (mmWave) massive multiple-input multiple-output (MIMO) systems, which can achieve significant throughput gains by leveraging large-scale antenna arrays. Adaptive radio frequency (RF) chain activation (ARFA) is a key technique for reducing power consumption without severely degrading the achievable rate, thereby enhancing the total EE of 6G MIMO systems. In this paper, we propose a minimum-cost maximum-flow (MCMF)-based ARFA scheme to reduce unnecessary power consumption and maximize the total EE of uplink mmWave cell-free massive MIMO systems. Simulation results indicate that the proposed approach can significantly improve the total EE while maintaining a relatively high achievable rate and acceptable computational complexity.

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Bo Yu, Abdol Hamid Aghvami, Mohammad Shikh-Bahaei. 2026-10-12. Energy-Efficient RF Chain Activation for Uplink mmWave Cell-Free Massive MIMO Systems: A Minimum-Cost Maximum-Flow Approach. https://arxiv.org/abs/2610.17478

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