Uplink Security Analysis of Hybrid RF-FSO Cooperative Satellite-Aerial-Terrestrial Networks

This work investigates the secrecy outage per-formance of the uplink transmission of hybrid radio-frequency (RF)-free-space optical (FSO) cooperative satellite-aerial-terrestrial network (SATN). Specifically, we adopt most popular content wireless caching scheme at aerial relay, while a group of eavesdropping aerial terminals (Eves) try to over-hear the confidential information. In particular, considering the transmit antenna selection (TAS) at the source and the maximal ratio combining (MRC) at the aerial relay, and the randomness of satellite receiver, relay, and Eves, the secrecy outage performance of the cooperative uplink transmission in the considered SATN is investigated and a closed-form analytical expression for the end-to-end secrecy outage probability (SOP) is derived. Finally, Monte-Carlo simulations are shown to verify the accuracy of our analysis.