A Game-Theoretic Approach for Energy-Efficient Contention-Based Synchronization in OFDMA Systems

The purpose of this paper is to provide a novel energy-efficient perspective to the problem of contention-based synchronization in orthogonal frequency-division multiple-access communication systems. This is achieved by modeling the terminals and their corresponding receivers at the base station as economic and rational agents that engage in a noncooperative game. In the proposed game, each one trades off its available resources (transmit power and detection strategy) so as to selfishly maximize its own revenue (in terms of probability of correct detection) while saving as much energy as possible and satisfying quality-of-service requirements given in terms of probability of false alarm and timing estimation accuracy. The existence and uniqueness of the equilibrium of the game are studied. In particular, a necessary and sufficient condition on the system parameters is given for the equilibrium to exist. An iterative and distributed algorithm based on best-response dynamics (at the transmit side) and a practical parameter estimation (at the receive side) are proposed to achieve the equilibrium point. Numerical results are used to highlight the effectiveness of the proposed solution and to make comparisons with existing alternatives in terms of power consumption, synchronization time, and estimation accuracy.