Space-to-Ground Optical Communication Downlink Scheduling Under Uncertainty of Link Availability

Space-to-ground optical communication (STGOC) utilizes laser beams to establish bidirectional links between satellites and ground stations (GSs), which are sensitive to cloud blockage. In practical STGOC downlink scheduling, the uncertainty of link availability caused by cloud motion and dissipation is inevitable. We are the first to address STGOC downlink scheduling under the uncertainty of link availability, where the objective function aims to maximize the amount of data downloaded from the satellites. We provide a formulation of the scheduling problem based on Scenario Generation Approximating (SGA) while preserving the formulation linearity. A Greedy Heuristic-based algorithm is designed to solve the problem. Simulation results indicate that considering uncertainty can enhance data throughput, with the average optimality gap being 0.61%, while the running time is reduced compared to Gurobi and Kuhn-Munkres-based methods.