Optimization Strategy for Single-satellite to Multi-station Data Transmission

In order to solve the problems of link handover time selection and complex relay scenarios in the multi-station data relay problem, a multi-station data relay method based on link handover time optimization was proposed, which simplified the multi-station relay scene and selected the optimal relay time, so as to improve the transmission time of data relay transmission. In this method, the mathematical description of multi-station relay is established based on the satellite-ground model and the motion constraints of the mechanical antenna, and the expression method of the link switching time between the satellite and the ground station is constructed. Based on the characteristics of mainstream low-orbit remote sensing satellites and ground stations, the relay scenarios of satellite-to-ground data transmission are established, the characteristics of their visible time arcs are summarized, and a two-station optimization strategy for complex multi-station relay scenarios is constructed. Finally, the typical satellite-to-ground data transmission model simulation is used to verify the data transmission relay method with optimization strategy constructed in this paper. The simulation results show that there are 32.0% relayable data transmission arcs in the data transmission links between satellite and the three typical ground station located in China, of which the three-station relay scenario accounts for 17.9%, and the three-station relay scenario can be simplified into a two-station relay scenario through the optimization strategy. In the link handover interval of multiple stations with visible arcs, there is a relay time with the shortest relay time, and the shortest link switching time can be shortened by up to 25% compared with the worst relay time after using the relay time optimization strategy. Using the optimized data relay method for relay data transmission, the average time available for each time was increased from 7.61 minutes to 11.12 minutes.