Internet of Things-Enabled Overlay Satellite-Terrestrial Networks in the Presence of Interference

In this paper, we consider an overlay satellite-terrestrial network (OSTN) where an opportunistically selected terrestrial IoT network assist primary satellite communications as well as access the spectrum for its own communications in the presence of combined interference from extra-terrestrial and terrestrial sources. Hereby, a power domain multiplexing is adopted by the IoT network by splitting its power appropriately among the satellite and IoT signals. Relying upon an amplify-and-forward (AF)-based opportunistic IoT network selection strategy that minimizes the outage probability (OP) of satellite network, we derive the closed-form lower bound OP expressions for both the satellite and IoT networks. We further derive the corresponding asymptotic OP expressions to examine the achievable diversity order of two networks. We show that the proposed OSTN with adaptive power splitting factor benefits IoT network while guaranteeing the quality of service (QoS) of satellite network. We verify the numerical results by simulations.