An efficient SIR-first adaptive power control method in cognitive radio network

Efficient power management is very important in wireless communication network. Cognitive Radio (CR) has been proposed to improve the spectrum utilization by sensing and accessing idle spectrum. However, for CR mobile users with limited battery power, transmitting at high power will increase the interferences and reduce the lifetime of both users and the network. In this paper, a double-threshold adaptive algorithm based on game theory is used to optimize the power allocation for users in CDMA cognitive radio network. Iterative formula is derived and proved to have Nash Equilibrium solution, by which the power vector of users can be calculated. The experiment results indicate that the proposed power control method has both characters of Sarah Koskie's and Power Balancing algorithm, which ensures all users' SIRs only with little extra power consumption. It maintains the fairness of all CR users, which is more suitable in Qos first networks.