A Suboptimal Routing Algorithm for Massive LEO Satellite Networks

In a massive Low Earth Orbit(LEO) satellite network without inter-satellite links(ISLs), connection between source node and destination node can be established through satellite-ground links. Utilizing satellite network topology in time virtualization algorithm and assuming that the current traffic of satellite-ground links which is used as the value of the topology correlation matrix can be perceived, the network uses the Dijkstra algorithm to obtain the shortest path of the current total network traffic and thus implements load balancing of the constellation system. Due to the large number of satellites, the network topology is complex and time varying, it is difficult to find the optimal path in a short time, so a suboptimal routing algorithm based on network topology is proposed in this paper. The local network topology is obtained by using the positions of the source and destination gateway, and the number of satellites and gateways used to establish the correlation matrix of the Dijkstra algorithm is reduced. Through the simulation analysis, the average computational complexity of this algorithm is much lower than that of the global optimal routing algorithm, and the average propagation delay of routing is almost the same. When the network load is normal, the system performance is almost the same with the global optimal routing algorithm.