Abstract:

The power control method for Cognitive Radio Networks (CRN) is investigated in this paper, which is based on the Nash bargaining cooperative game theory. A utility function based on (Signal-to-Interference plus Noise) SINR is proposed for this model. Based on the Nash Bargaining Solution (NBS) from the cooperative game theory, the power control method not only provides the power level of users that are Pareto optimal from the point of view of the whole system, but also are consistent with the fairness axioms of game theory. Meanwhile, we prove the NBS is essentially a general form of the proportional fairness. Under the constraints from the interference temperature of the primary user and the maximum transmit power of the cognitive users, and according to NBS Nash theorem, we convert the power control problem into the optimization problem with multiple constraints. Through introducing the Lagrange operators, the optimal power levels are obtained, and achieving the SINR threshold requirements are met. The simulation results show that our algorithm has a faster convergence rate, and compared to reference traditional method, our algorithm can effectively improve the understanding between users, the fairness of the cognitive users and the overall performance of the whole system.

Key words: Cooperative game theory, Nash Bargaining Solution, Power control, Cognitive radio networks