Spectrum sensing interval optimization and power control for energy efficient cognitive radio networks
Energy efficient cognitive radio networks can simultaneously improve spectrum efficiency (SE) and energy efficiency (EE) of wireless communication networks. This paper studies energy efficient spectrum sensing interval, spectrum sensing energy and transmit power allocation scheme of the secondary user (SU) in CR networks. The EE maximization problem subject to the transmit power constraint and average primary user (PU) interference constraint is formulated as a non-convex optimization problem. Based on the quasiconcave property of the optimization problem, the original problem is transformed into an equivalent concave problem and a Dinkelbach's method based iterative algorithm is used to solve the problem. As a special case, the throughput maximization problem is also investigated. Through simulation results, the impact of transmit power constraint and PU interference constraint on the EE and throughput of the SU are analyzed.