Selecting the Sensing Method in Cognitive Radio and Future Networks: A QoS-Aware Fuzzy Scheme

Scarcity of the radio frequency spectrum available for use by the vast number of wireless devices is already a challenge faced by ubiquitous communication networks, including the Internet of Things. The Cognitive Radio (CR) technology provides promising solutions to address part of such challenges. CR is based on allowing the so-called holes, the spectrums that remain unoccupied by their licensed users, to be utilized by others. To detect these holes, several spectrum sensing methods have been proposed by researchers. Each of these methods has its advantages and shortcomings for a given CR operation scenario. In particular, sensing methods can greatly affect the QoS levels of applications for various users of CR networks. In this paper, the effects of various spectrum sensing parameters and functions on the QoS levels of applications running on CR devices are reported. Based on those, the authors propose a QoS-aware fuzzy scheme for selecting the proper sensing method, from the catalog of available ones. We show that the proposed scheme mitigates the degrading impacts of the sensing operations on the QoS levels of a diverse range of CR-based applications.