Hybrid satellite-terrestrial spectrum sharing system with opportunistic secondary network selection

We consider a hybrid satellite-terrestrial spectrum sharing system wherein multiple terrestrial secondary networks coexist with a primary satellite network. We propose an amplify-and-forward based cooperative spectrum sharing protocol by employing an opportunistic secondary network selection (OSNS) scheme. The best secondary network is selected to minimize the outage probability of primary satellite system and to achieve spectrum access. With overlay approach, the selected secondary network allocates its partial power to relay the satellite signal and utilizes the remaining power to transmit its own signal. We derive closed-form expressions of outage probability for both primary and secondary networks and examine their achievable diversity order over hybrid fading channels. Numerical and simulation results validate our analysis and highlight the performance gains of the considered system with OSNS scheme.