Abstract: In view of the phenomenon that constellation service performance worsens due to operation or failure of constellation satellite in orbit, the research progress of constellation backup strategy was reviewed. Firstly, the basic situation and backup status of navigation constellation and communication constellation were summarized. The backup strategies of different constellations were concluded. Secondly, three different constellation backup strategies,i.e., in-orbit backup, parking orbit backup and ground backup, were highlighted. Then in terms of satellite failure, satellite reliability, satellite availability, constellation state probability and constellation system availability, the research progress in the key factors of the constellation backup strategy were reviewed. Thirdly, the main models and methods for the analysis of constellation backup strategy were introduced, including Petri nets, Markov chains and inventory theory. Finally, the future research directions of constellation backup strategy were prospected.

Key words: constellation backup, satellite reliability, constellation availability, Petri nets, Markov chains, inventory theory