Reliability evaluation of all-user terminals in LEO satellite communication network based on modular reduction

LEO satellite communication network has a large number of satellites distributed in low orbits, which leads to multiple coverage of many areas on the ground. It is hard work to describe and evaluate the reliability of LEO satellite communication network. To solve this problem, the reliability of all-user terminals in LEO satellite communication network is defined, and the corresponding reliability evaluation method is proposed in the paper. Due to the large scale of the interstellar network, a modular reduction algorithm using the modular network instead of the original network for state decomposition is proposed in this paper. Case study shows that the calculation time of the proposed method is equivalent to 6.28% of the original state space decomposition algorithm. On this basis, the reliability of LEO satellite communication network is further analyzed. It is found that the reliability of LEO satellite network was more sensitive to the reliability of Inter-Satellite link and the satisfaction of global coverage in the early stage, and it is more sensitive to the reliability of the satellite in the later stage. The satellite-ground link has a relatively constant impact on of LEO satellite network.