Virtual Topology for LEO Satellite Networks Based on Earth-Fixed Footprint Mode

In this letter, a formal model is given to clarify the dynamics and fixity of the virtual topology based on Virtual Node method for Low Earth Orbit (LEO) satellite networks. The formal model can generate few snapshots, well-proportioned snapshot length and less path changes than the physical topology with Satellite-fixed footprint mode. Moreover, it can effectively avoid path stretch and contraction deriving from the satellite's movement. Its application in Multi-layered satellite networks can also overcome the main limitation of conventional Satellite Group and Group Manager method.