Research On Cooperative Game Routing Strategy For LEO Satellite Network

LEO constellation with multiple LEO satellites can achieve truly global seamless coverage for communication.With outstanding advantages of low transmission loss,short communication delay,strong anti-destruction ability and miniaturization of terminals,LEO constellation has attracted worldwide enthusiasm in research and has become a promising direction in the next generation of mobile communication systems.In a LEO satellite network,the routing and control mechanism is a key that affects the overall performance of the satellite network.How to ensure the reliability of the routing paths and the load-balancing of the traffic distribution is the critical problem to be solved in the current LEO satellite network research.In view of the characteristics and existing problems of LEO satellite constellation mentioned above,this thesis applies the cooperative game routing strategy and implements its network simulation experiments for LEO satellite networks.The major work and achievements are as follows:(1)A distributed network-status aware self-adaptive routing algorithm based on ISL status and node workload is proposed.Every satellite is independently responsible for forwarding datagrams in its queue,with information about network link status piggybacked in the transmitted datagrams.Such information helps understand and predict the network workload status on each direction of the satellite outgoing links,and is used for near-optimal selection of datagram outbound links to achieve load balancing and multi-path routing.(2)An optimal revenue routing algorithm for LEO satellite network based on cooperative game theory is proposed.The algorithm is based on the above network-status aware process,and draws on the optimal strategy of cooperative game theory in economics.According to the predictable topology of the LEO satellite constellation network,all LEO satellite relay nodes in the routing path from the source satellite node to the destination satellite node are regarded as a cooperative game alliance.The real-time status information of nodes and the network performance are used to define the cooperation revenue of routing alliance.The Shapley value is used as a solution to the cooperative game to deterrmine the current optimal routing path of each data packet.(3)Simulations are conducted on the NS2 network simulator with a designed LEO constellation,to implement and evaluate the effectiveness and efficiency of the proposed algorithms.Experimental results show that the data packets transmission delay and network load balancing have been significantly improved,with a few more hops in the selected routing paths compared with the traditional Dijkstra's Shortest Path algorithm and other multi-path routing strategies.