A Non-Cooperative Power Control Game for Multi-Carrier CDMA Systems

TL;DR

This paper introduces a game-theoretic power control method for multi-carrier CDMA systems, where users optimize energy efficiency by selecting the best carrier, leading to improved overall utility at equilibrium.

Contribution

It proposes a novel non-cooperative game model for power control in multi-carrier CDMA systems, including existence, uniqueness, and a distributed algorithm for equilibrium.

Findings

Users transmit only on the best carrier at equilibrium.

The proposed algorithm converges to a unique Nash equilibrium.

Total utility at equilibrium is significantly improved.

Abstract

In this work, a non-cooperative power control game for multi-carrier CDMA systems is proposed. In the proposed game, each user needs to decide how much power to transmit over each carrier to maximize its overall utility. The utility function considered here measures the number of reliable bits transmitted per joule of energy consumed. It is shown that the user's utility is maximized when the user transmits only on the carrier with the best "effective channel". The existence and uniqueness of Nash equilibrium for the proposed game are investigated and the properties of equilibrium are studied. Also, an iterative and distributed algorithm for reaching the equilibrium (if it exists) is presented. It is shown that the proposed approach results in a significant improvement in the total utility achieved at equilibrium compared to the case in which each user maximizes its utility over each carrier independently.