Green power allocation for cognitive radio networks with spectrum sensing

Green wireless communication has drawn ample interest in the 5G cellular networks. In this article, we investigate an energy-efficient power allocation with spectrum sensing for cognitive radio (CR) networks. The optimization problem is formulated as a ratio of the sum rate (SR) to the total power consumption in the signal transmission and spectrum sensing subject to the total power constraint. Because the original optimization problem is nonconvex, we adopt Dinkelback's method and propose an optimal energy-efficient power allocation scheme that iteratively improves the energy efficiency (EE) performance of the CR network and finally gives an optimal solution. In addition, an expression for the optimal solution is derived through the dual-decomposition method, and its performance is validated through simulation results. The impact of the probability of detection (P-D) and the probability of PU activeness (P-A) on the achievable average EE and SR is demonstrated when the CR network is designed from the energy-efficient perspective. (c) 2018 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.