volume | PIER Journals

Abstract

User-centric cell-free massive multiple-input multiple-output (UC-CFmMIMO) networks require efficient uplink power control to ensure both fairness and spectral efficiency (SE). However, existing schemes such as fractional power control (FPC) struggle to balance minimum SE and total SE, especially in large-scale deployments. To address this, we propose a grey wolf optimization (GWO)-based power control scheme, optimizing power allocation to maximize minimum SE while also improving total SE. Simulation results in a 1 km × 1 km UC-CFmMIMO network with 50 access points (APs) and 10 user equipments (UEs) show that our method outperforms FPC and fixed-point algorithm in both fairness and SE. Specifically, it achieves a minimum SE of 1.37 bit/s/Hz (vs. FPC: 0.13 bit/s/Hz) and a total SE of 39.17 bit/s/Hz at 100 APs (vs. FPC: 36.77 bit/s/Hz). The proposed approach scales effectively with AP and UE densities, making it a practical solution for future UC-CFmMIMO deployments.

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Dr. Nguyen Van Cuong

Dr. Bo Quoc Bao

Dr. Hoang Manh Kha

Dr. Tong Van Luyen