基于多级库存管理理论的导航星座可用性研究

In view of the problems existing in the current research on backup strategies for constellations, such as the single method and the neglect of short-term satellite failures, as well as the insufficient in-depth study of backup strategies using Markov theory, this paper proposes a constellation availability research method based on multi-level inventory management theory and considering constellation status. Firstly, a mathematical model of constellation backup strategy is established with the guarantee rate of backup satellites as the index. Then, based on Markov theory, a mathematical model of constellation service availability is further established by combining the availability of individual satellites and the probability of constellation status. Finally, a case analysis and comparison are conducted using a certain navigation constellation as an example. According to the calculation results of the model, the changes in the probability of constellation failure status are explored; the influence of the deployment position, replenishment timing, and increase in the number of backup satellites on improving constellation service availability is given; and it is verified that the impact of short-term failures on constellation availability is similar to that of long-term failures and cannot be ignored in engineering applications.