Physical layer secrecy performance analysis of multi-user hybrid satellite-terrestrial relay networks

Abstract

This paper investigates the secrecy performance of a downlink multi-user amplify-and-forward hybrid satellite-terrestrial relay network (HSTRN) with opportunistic scheduling of terrestrial users. By considering Shadowed-Rician fading for satellite link and Nakagami-m fading for terrestrial links, we derive accurate and asymptotic expressions for secrecy outage probability (SOP). Based on the asymptotic behaviour of SOP expression at high signal-to-noise ratio regime, we illustrate practical insights on the achievable diversity order of the system. Subsequently, we also deduce the expression for probability of non-zero secrecy capacity. Finally, numerical and simulation results are provided to vindicate our analysis and to show the impact of various key channel/system parameters such as shadowing severity and number of users on the physical layer secrecy performance of HSTRNs.