Optimal Spectrum Sensing Time and Transmit Power Based on Energy Efficiency in Cognitive Radio Networks

Abstract

Abstract-The optimization problems of spectrum sensing time and power in CR network are investigated in this paper. Firstly, the energy efficiency optimization problem, whose variables that should be jointly optimized are transmit power and sensing time of cognitive users, is derived. Then, the relations between the energy efficiency and transmit power, the energy efficiency and spectrum sensing time are analyzed, respectively. The numerical results show that CR network can achieve almost the maximum achievable data rate with significant energy saving through the joint optimization.