Security in physical layer of cognitive radio networks

Abstract

Fifth-generation (5G) networks and beyond are anticipated to support a vast number of connections and services. Due to the enormous amount of confidential data shared between devices in these networks, the risk of security vulnerabilities escalates proportionally. Cognitive radio networks (CRNs) are no exception since they are vulnerable to a variety of physical-layer threats; hence, a physical-layer approach is necessary to safeguard these networks. Consequently, physical-layer security (PLS) has recently been applied for examining and strengthening the security of wireless networks, including CRNs. In light of this, this chapter examines a brief overview of CRNs, as well as the main physical layer attacks and their respective primary countermeasures. In addition, the employment of energy harvesting (EH) techniques to improve CRNs security is discussed. The security threats on cognitive unmanned aerial vehicles (UAVs) and their primary defense mechanisms are presented. In addition, the consideration of cascaded fading channels and their effect on the security of CRNs are explored. Finally, this chapter includes conclusions and potential future directions.