Energy-Efficient Cooperative Spectrum Sensing with Quality-of-Service Provisioning

Abstract

Energy efficient communication techniques have attracted a lot of attention due to operational device requirements and global environment concerns. In this paper, we investigate energy efficient cooperative spectrum sensing (CSS) in cognitive radio (CR) networks with Quality-of-Service (QoS) provisioning. The energy efficiency (EE) of the CR network is defined as the ratio of the average spectrum efficiency over the average power consumption. To maximize the EE, both the sensing time and secondary user's (SU's) transmit power are optimized. We propose mathematical reformulation of the problem in a way that allows uni-modality to be used to confirm the existence of optimal solution, and Algorithm 1 is proposed to solve the optimization problem. Then, an efficient Algorithm 2 is proposed to maximize the EE under the constraint that the spectrum efficiency (SE) requirement is satisfied. Computer simulations show that, in order to improve the EE of the CR network, joint optimization of sensing time and SU's transmit power should be performed. And different QoS requirements require different system parameters.