Outage Performance of Satellite-Terrestrial MISO Downlink Transmission

The satellite-terrestrial communication system is considered to be a necessary way to provide global broad coverage. Particularly, as the low Earth orbit (LEO) constellation system develops rapidly and LEO satellites operate in low orbits with heights lower than 2000 km, short serving time and frequent handovers are necessary for LEO satellite-terrestrial communications. Thus, diversity gain via multiple satellites needs to be considered. In this work, the code-division multiple access scheme is adopted for the downlink delivery while multiple satellites are trying to simultaneously deliver information bits to a terrestrial terminal. Moreover, an aerial platform generates interference signals to interfere with the information delivered from the satellites to the terrestrial terminal. Then, we derive an outage performance analysis model by deriving the closed-form analysis expression for outage probability. Finally, the Monte Carlo simulation is presented to show how the system parameters, e.g., the synchronization of the clock and the frequency drifts among the multiple terrestrial users, influence the downlink transmission performance of target satellite-terrestrial systems.