A Fair and Scalable Power Control Scheme in Multi-cell Massive MIMO

TL;DR

This paper introduces a scalable power control scheme for multi-cell massive MIMO systems that balances fairness and spectral efficiency by maximizing the geometric mean of per-cell spectral efficiencies, with proven convex optimization solutions.

Contribution

A novel power control scheme that maximizes the geometric mean of spectral efficiencies, addressing scalability and fairness in multi-cell massive MIMO systems.

Findings

The proposed scheme improves fairness and spectral efficiency balance.

Convex reformulation enables efficient optimization.

Simulation results demonstrate performance benefits.

Abstract

This paper studies the transmit power optimization in a multi-cell massive multiple-input multiple-output (MIMO) system. To overcome the scalability issue of network-wide max-min fairness (NW-MMF), we propose a novel power control (PC) scheme. This scheme maximizes the geometric mean (GM) of the per-cell max-min spectral efficiency (SE). To solve this new optimization problem, we prove that it can be rewritten in a convex form and then solved using standard tools. To provide a fair comparison with the available utility functions in the literature, we solve the network-wide proportional fairness (NW-PF) PC as well. The NW-PF focuses on maximizing the sum SE, thereby ignoring fairness, but gives some extra attention to the weakest users. The simulation results highlight the benefits of our model which is balancing between NW-PF and NW-MMF.