Research Of Multi-service LEO Satellite Network Handover And Routing Technologies

LEO satellite system in the global coverage,high real-time mobile communication field has a very prominent advantage.Compared with the GEO system,LEO needs to transmit power smaller,signal transmission delay and has a smaller,but because of the high-speed motion characteristics of LEO satellite,the user in each district covering the detention time is short,need to continue to point to another mobile beam from a spot beam passive.In order to ensure ongoing communication service without interruption,inter satellite handover and beam in a continuous call process will inevitably happen frequently,frequent switching process will not only introduce the handoff delay unbearable,resulting in a large number of missing data,and excessive switching makes signaling overhead unnecessary.So the switch has become one of the key factors affecting the overall performance of LEO satellite communication system.How to use the switching technology more reasonable,improve the performance of low orbit satellite communication system,the rational use of precious satellite bandwidth and resources,satellite communication has become the key success,has important practical.At the same time,LEO satellite mobile communication network must have a mechanism to record user location information of nodes,when a communication request,the network can connect through all possible target user node of the network interface,sent to the target user node call request information on the current position for the target node;at the same time,the user node switch the access node,can maintain the communication process is not interrupted.In order to reduce the overhead of mobile management,it is necessary to consider the influence of the high speed motion of the satellite nodes on the implementation of the protocol.With the rapid development of satellite communication technology,interplanetary routing has become a very important key technology of satellite communication system.In this paper,three important problems in LEO satellite communication system,such as inter beam switching,inter satellite handover and inter satellite routing,are studied.1?proposed a new priority considering the different channel reservation scheme(MPDCR),to determine the movement of the LEO satellite and based on the predictability in do not need to know the exact location of the user,but based on real-time movement,considering the quality of service from the global channel,dynamic calculation is assigned to each user and beams with different priority the number of different types of business.2?an integrated weighted inter satellite Handoff Strategy Based on genetic algorithm is proposed,as well as the access process of LEO satellite network under multi service conditions.3?the LEO satellite network routing algorithm for Pareto multi objective genetic,considering the population density of different flow maldistribution,and delay path selection in high latitude concentration effect,to achieve the overall balance of flow control;consider the LEO satellite network inter satellite link and frequent switching,reduce the rerouting;also was considered for the first time the problem of satellite in the depth of discharge battery life of satellite earth shadow region;put forward to path delay,path duration,maximum path bandwidth,and the discharge index of the five target of the target function of GA,the Pareto multi-objective genetic algorithm(PMGA)for path set selection,finally according to the different business on different routing requirements get,routing cost in different service under each routing path selection as the basis,to achieve multi service Qos routing.