A Multi-attribute Decision Handover Strategy for Giant LEO Mobile Satellite Networks

Due to the characteristics of low orbital height and large number of satellites, the giant Low Earth Orbit (LEO) satellite network has more frequent handovers than ordinary LEO satellite communication systems. There are a large number of satellites available for handover, and the handover problem is more prominent. In this study, a handover strategy suitable for all users is designed for the inter-satellite handover in the giant LEO satellite network. This strategy designs two different handover methods for different handover users and new callers. For users who can predict the handover time, a multi-attribute decision handover strategy based on a directed graph is adopted. It uses the satellite service timetable (including satellite coverage at each time and each index value) to construct a satellite handover directed graph, and combine the handover path to reserve channel resources for users. For handover users and new callers who cannot predict the handover time, a multi-attribute decision handover strategy based on combined weights is adopted. The best candidate satellites are obtained by weighting each index combination, distinguishing user types and service types, and using channel queuing strategies to access satellites according to different priorities. The simulation results prove that this strategy can reduce the number of handovers while taking into account the signal strength and system load balance, and can effectively reduce the handover blocking rate.