Research On Dynamic Routing Strategy And Algorithm In LEO Satellite Networks With Laser LSLS

Adopting laser ISLs to transfer information in satellite network has been a trend in the world, accordingly, which will realize the satellite network with broad band data in the future. But it is hard to realize the dynamic adaptive routing for the particularity of the satellite networks with laser ISLs. This dissertation is concerned with theory of dynamic routing in LEO satellite networks with laser ISLs which is emulated with Matlab software to prove the research production.In the dissertation, firstly the topological structure of network is analysed. It introduces the theory of satellite coverage, geometry relationship of laser ISLs, and then analyses simulated curves of dynamic characteristic with elevation, azimuth, distance and time delay. The periodicity and predictability of constellation could be used to provide the basic of quantitative analysis to design routing arithmetic. At the same time, the annoy factors of laser ISLs in IOC network are discussed, which are the impact of the dynamic environment on satellite platform, the coupled dynamic environment between IOC terminal and satellite platform and background noise on laser ISLs.Next, Traffic model of IOC network is established, which concludes traffic flow on node and globe traffic model. Base on information generated theory in optical network, time delay of node is analyzed by use of queue theory. The simulated results show that time delay is statistic random distribution. The traffic variation and statistical characteristics of node are gained by adopting globe traffic model to simulate. Routing strategy could equalize the traffic of networks, which was led in IOC network and improve the utility of network.Base on the topological characteristics of network and traffic model, the routing strategy of satellite network is presented, the intersatellite routing strategy of IOC network, discrete virtual topology routing, is analyzed. With running the intersatellite routing strategy, this dissertation brings forward a improved dynamic routing arithmetic, optimized hops shortest path (OHSP) arithmetic, which adopts LSW replace generic LW. LSW includes time delay, the dynamic metabolic of topological structure and traffic flow, the measure of dynamic routing reconfiguration is discussed. The simulated results show that the OHSP arithmetic could adapt the variation of topological structure and traffic flow. With confinement of LSW, the OHSP arithmetic could reduce the number of routing handoff and reduce BER of communication. Then it could enhance the performance of network.This dissertation will lay a foundation of design basis and theoretical for the research of routing in network development with laser ISLs and a useful reference for making it practical.