Design And Implementation Of Simulation System For Large LEO Satellite Constellations

With the maturity of cheap launch technology,the LEO satellite constellation is entering a rapid development stage,showing an explosive growth of more than ten times compared with the traditional constellation size.Due to the high dynamic and large-scale characteristics of the LEO satellite network,relevant research fields have gradually become a hot spot.In this paper,a general constellation network simulation system is proposed and designed to support the research and experiment of constellation network configuration in order to solve the problem of lack of appropriate simulation tools in the research of large-scale low orbit satellite constellation.This system can provide basic simulation capabilities in large-scale constellation scenarios and is easy to use and modify.After conducting requirement analysis and system design,this article implements the system based on Python programming language and libraries such as Qt and VTK,and provides various practical functions.The business layer of the system is divided into three modules:constellation,routing,and visualization.The constellation module includes satellite dynamics,ground equipment,and link management submodules.The satellite dynamics submodule automatically generates satellite positions based on parameters and TLE files,while the ground equipment submodule is responsible for updating the equipment positions that rotate with the Earth.The link management submodule provides tools for limiting spatial links and basic link establishment methods.The routing module implements network routing experiments based on the network topology of the constellation module,while the visualization module provides flexible UI color schemes,layer functions,and screenshot functions,supporting users to easily output constellation network screenshots.To improve the computational performance of the system,this article specifically designs a data structure and a 3DGeohash encoding method,and adopts techniques such as numba acceleration.In addition,the system can combine with mainstream emulator ns3 to provide packet level simulation.The test results show that the system can effectively support the research and experiment of large LEO satellite constellation and achieve the expected design goals.