Research On Stability Of Hierarchical Sattellite Network

In the future developing trend of integrated communication networks, as the most important component of this system, satellite network has been paid much attention, but the reaserch on many key technological questions is still in the beginning. From the initial development of geostationary orbit satellites to the current LEO or MEO single-layer constellations and multilayer satellite networks, in the special conditions of global coverage, emergency and military affairs, the communication advantage of satellites is more and more obvious. Along with the diversification of traffic, backbone structure of satellites and high efficiency of transmission, hierachical satellite network becomes the basic model in most of the satellite network design. Therefor, how to achieve the effective management and stable design of large-scale, hierachical satellite network is the key point in the entire satellite communication system.Based on the hierachical satellite network characteristic of high dynamic topology, long transmission delay, multilayer structure and shortage of resources, some related questions about stability of hierachical satellite network are analyzed in this paper.Firstly, topological characteristic of hierachical satellite network is analysed. Becaused of high dynamic characteristic of non-synchronous satellites, there is a great difference between satellite networks and ground communication networks. Therefore, in this section, based on the analysis of the geometrical structure of hierachical satellite network, the hypercube topology and hiberarchy structure are proposed. Also, the stable backbone topology model of hierachical satellite network is established. In addition, the serial queuing transmission optimization model is analysed in order to provide theoretical support to the research of stability of hierachical satellite network.Secondly, stability and survivable routing strategy of hierachical satellite network is analysed. Based on the parameters of stability and network traffic model in the history, the stable measuring function of hierachical satellite network is proposed. According to the analysis of discrete model and delay jitter of the satellite network, the switch strategies of QoS routing and feasibility of stable topological structure of hierachical satellite network is analyzed. Finally, stable design of hierachical satellite network is analysed. Based on the relativity of traffic and stable measuring function, physical stratification of subnet is proposed. According to the serial queuing transmission model, constraint optimal equation, logical weight of satellite and stable input model of traffic, the logical grouping method is proposed. By the theoretical analysis and simulation, the number and location of gateway of the subnet is optimized.According to the analysis of stability of hierachical satellite network, the design method based on backbone structure of hypercube topology and stable subnet is proposed. And this new method will be helpful to the efficient management and stable organization of the future large-scale hierachical satellite network.