Three-Level Mega Satellite Constellation Backup Strategy

The recent growing trend to develop ultra-large-scale (mega) satellite constellations with low-cost small satellites is becoming more and more common. In this paper, we propose a three-level backup strategy based on METRIC (Multi-echelon technique for recoverable item control) theory for a mega satellite constellation. Firstly, the principle of the three-level backup strategy model based on METRIC theory is explained, and the three-level backup mathematical model with constellation availability as the constraint and backup cost as the optimization objective is established. In this model, we consider three backup modes: ground backup, parking orbit backup, and constellation plane backup. Then a certain type of mega low-orbit satellite constellation is taken as the case study object. Genetic algorithm (GA) and marginal analysis (MA) are used to solve the model and analyze the parameters that have the greatest impact on the results. Last but not least, the advantages and disadvantages of genetic algorithm and marginal analysis in solving this optimization problem are discussed.