A Distributed Game-Theoretic Solution for Power Management in the Uplink of Cell-Free Systems

TL;DR

This paper introduces a distributed game-theoretic power control method for uplink in cell-free systems, optimizing energy and spectral efficiency through a potential game framework with a tunable parameter.

Contribution

It presents a novel potential game-based distributed power control scheme with a scalar parameter to balance energy and spectral efficiency in cell-free systems.

Findings

Improves energy utilization in user terminals' batteries.

Balances spectral and energy efficiency effectively.

Ensures convergence to Nash equilibrium.

Abstract

This paper investigates cell-free massive multiple input multiple output systems with a particular focus on uplink power allocation. In these systems, uplink power control is highly non-trivial, since a single user terminal is associated with multiple intended receiving base stations. In addition, in cell-free systems, distributed power control schemes that address the inherent spectral and energy efficiency targets are desirable. By utilizing tools from game theory, we formulate our proposal as a noncooperative game, and using the best-response dynamics, we obtain a distributed power control mechanism. To ensure that this power control game converges to a Nash equilibrium, we apply the theory of potential games. Differently from existing gamebased schemes, interestingly, our proposed potential function has a scalar parameter that controls the power usage of the users. Numerical results confirm that the proposed approach improves the use of the energy stored in the battery of user terminals and balances between spectral and energy efficiency.