Date Added: May 2012
In the spectrum underlay model, cognitive radios can access the spectrum owned by primary users if they can limit their interference power below a certain threshold, called Interference Temperature Limit (ITL). In this paper, the authors study the power control problem under ITL. By considering both efficiency and fairness, the power control problem is modeled as a cooperative game. A power control scheme based on Nash Bargaining Solution (NBS) is proposed. They present a Distributed Power Control (DPC) algorithm based on NBS. The convergence of DPC algorithm is proven by theoretic analysis. Simulation results show that proposed DPC algorithm achieves an effective tradeoff between fairness and efficiency.