Distributed Power Control for Cognitive Radio Networks, Based on Incumbent Outage Information

The interference management problem in cognitive radio networks is in this paper, tackled from the transmitter power control perspective so that transmissions by cognitive radios does not violate the interference level thresholds at incumbent users. We modify cellular distributed power control algorithms to suit the cognitive radio framework by exploiting spectrum use and radio environment knowledge for incumbent user location estimation in worst-case scenario. Most literature employs worst-case analysis to guarantee robustness thereby trading off optimality. We therefore, propose a stochastic approach which allows the cognitive radio network, access the extra capacity based on incumbent user outage information with guarantees on interference protection to the incumbent user at all times. This paper therefore shows that the proposed distributed power control strategy is robust with the benefit of increased spectral efficiency compared to its worst case counterpart.