Abstract

We investigate the realistic propagation conditions effects on wireless physical layer security, which are different from classical Rice and Rayleigh fading. Specifically, we study how the superposition of a number of dominant specular waves and diffusely propagating components impacts the achievable secrecy performance. We derive analytical expressions for the secrecy outage probability and the average secrecy capacity, which have similar complexity to other alternatives in the literature derived for simpler fading models. We provide very useful insights on the impact on physical layer security of (i) the number; (ii) the relative amplitudes and (iii) the overall power of the dominant specular components. We show that it is possible to obtain remarkable improvements on the system secrecy performance when: (a) the relative amplitudes of the dominant specular components for the legitimate channel are more unbalanced compared to those of the eavesdropper’s channel, and (b) the power of the dominant components for the main channel is significantly larger than the power of the dominant components for the wiretap channel.