Uplink Pilot and Data Power Control for Single Cell Massive MIMO Systems with MRC

TL;DR

This paper develops optimal pilot and data power control strategies for single cell uplink massive MIMO systems, improving spectral efficiency by solving related optimization problems.

Contribution

It derives a closed-form solution for training interval length and formulates power control as optimization problems, including a geometric program for max-min SE.

Findings

Optimized power control enhances spectral efficiency compared to heuristics.

A closed-form solution for training interval length is provided.

An efficient algorithm for sum SE maximization is developed.

Abstract

This paper considers the jointly optimal pilot and data power allocation in single cell uplink massive MIMO systems. A closed form solution for the optimal length of the training interval is derived. Using the spectral efficiency (SE) as performance metric and setting a total energy budget per co- herence interval the power control is formulated as optimization problems for two different objective functions: the minimum SE among the users and the sum SE. The optimal power control policy is found for the case of maximizing the minimum SE by converting it to a geometric program (GP). Since maximizing the sum SE is an NP-hard problem, an efficient algorithm is developed for finding KKT (local maximum) points. Simulation results show the advantage of optimizing the power control over both pilot and data power, as compared to heuristic power control policies.