Energy-Efficient Power Control for Contention-Based Synchronization in OFDMA Systems with Discrete Powers and Limited Feedback

TL;DR

This paper presents a distributed, game-theoretic power control algorithm for OFDMA systems that enhances energy efficiency and synchronization accuracy with limited feedback, suitable for standards like IEEE 802.16m and LTE.

Contribution

It introduces a novel discrete power control game and a distributed algorithm that improves energy efficiency and synchronization accuracy under limited feedback conditions.

Findings

Enhanced energy efficiency compared to existing methods

Improved timing estimation accuracy

Requires reasonable feedback exchange

Abstract

This work derives a distributed and iterative algorithm by which mobile terminals can selfishly control their transmit powers during the synchronization procedure specified by the IEEE 802.16m and the 3GPP-LTE standards for orthogonal frequency-division multiple-access technologies. The proposed solution aims at maximizing the energy efficiency of the network and is derived on the basis of a finite noncooperative game in which the players have discrete action sets of transmit powers. The set of Nash equilibria of the game is investigated, and a distributed power control algorithm is proposed to achieve synchronization in an energy-efficient manner under the assumption that the feedback from the base station is limited. Numerical results show that the proposed solution improves the energy efficiency as well as the timing estimation accuracy of the network compared to existing alternatives, while requiring a reasonable amount of information to be exchanged on the return channel.