Physical Layer Security in Underlay Cognitive Radio Networks Over $\alpha-\mu$ Fading Channels

This paper investigates physical layer security of underlay cognitive radio networks with interference constraint over α-μ fading channels. Specifically, in the secondary network, a secondary source sends its confidential information to a secondary destination in the presence of a passive eavesdropper, under the constraint imposed by the primary receiver in the primary network. Specifically, we derive the exact expressions of intercept probability and ergodic secrecy capacity (ESC) for the considered system under α-μ fading channels. To extract more valuable insights, we also present the asymptotic analysis of intercept probability, which reveals that the system secrecy diversity order only depends on the fading parameters of the secondary source-secondary destination link, not on the fading parameters associated with the secondary source-secondary eavesdropper link and secondary source-primary receiver link. We also present some key observations for ESC when secondary source power with interference constraint is very large. The numerical and simulation results corroborate the validity of our analytical framework, and show the effects of channel parameters on the system secrecy performance.