Outage Analysis for STAR-RIS Assisted Satellite- UaV - Terrestrial System with NOMA

In this study, we investigated a STAR-RIS assisted satellite-unmanned aerial vehicle (UAV)-terrestrial system with non-orthogonal multiple access (NOMA). Specifically, a satellite source first sends the NOMA signals to a UAV relay and then the UAV transmits them to users through a STAR-RIS, which transmits and reflects the signals to the ground users by a energy splitting protocol. In addition, the randomness of the geometrical locations of the two users, i.e., their positions are assumed to be randomly distributed on the circular planes and circular ring planes, is taken into account. Using the series of Laguerre polynomials, we derived the closed-form expressions of outage probability (OP) for two users, and Monte-Carlo simulation verifies the accuracy of the expressions.