Abstract: Aiming at the orbital maintenance of the Walker constellation configuration in low Earth orbit (LEO), the perturbation motions and evolution of the constellation configuration caused by the Earth’s none spherical gravity and atmospheric drag perturbation are analyzed, the divergence of the constellation configuration is mainly reflected in the orbit altitude attenuation and phase drift caused by the inconsistency of the initial orbit parameters, and the result is asserted with the real orbital data of the first LEO constellation in China. According to the characteristics of the constellation, a relative phase maintenance strategy based on the reference satellite is proposed. Selecting one reference satellite to make the cumulative phase drift of all other satellites in the constellation relative to the reference satellite is minimized, the orbit altitude is raised/decreased relative to the reference satellite orbital altitude to maintain the relative positional relationship between the satellites. The practical application shows the effectiveness of this strategy, which reduces the complexity of the constellation configuration maintenance, saves fuel and shortens the time of orbit control, and provides a reference for the future constellation configuration maintenance in China.

Key words:  LEO Walker constellation, Configuration evolution, On-orbit data, Maintenance strategy, Orbit simulation