The Research Of Routing Strategy For LEO/GEO Satellite Network

In the satellite network system,because of the motion between relative satellites,the connection and disconnection of satellite link frequently happens,which makes the connection of the satellite link unstable.Satellite's resources are relatively limited,which makes the satellite's performance in the high QoS communication service not good.In addition,compared with the uniform distribution of satellite,the number of satellite network users is imbalanced due to landform and climate.These will cause the local hot spots easily appear in satellite network,which will cause local link congestion and result in a long delay and high packet loss rate of the whole network.The researchers at home and abroad have put forward many satellite network routing strategies in order to solve the problems mentioned above.The common satellite network routing strategies include QoS routing strategy,multi-service routing strategy and load balancing routing strategy.Based on the analysis of the existing satellite networks routing strategies,this thesis studies the problems of the satellite network,and puts forward routing strategies for LEO/GEO two-layered satellite network.The main work is as follows:(1)Considering QoS,multi service and load balancing together,we propose a multi-service satellite routing strategy based on space-time factor.In this method,the space-time factor is introduced into the link cost formula,and the routing table is calculated by link cost.The simulation results show that the routing strategy has better performance.The average packet loss rate of the whole satellite network is decreased,and the throughput is increased.(2)Due to the probability of link failure and interference in transmission is relatively large,using only single path to transmit is likely to cause data lost and damaged.In order to meet users' needs,multi-service and multi-user routing strategy based on multi path is proposed to reduce the data loss as far as possible.The simulation results show that the reliability of data transmission is improved and the data loss rate is reduced by using multi-path redundancy transmission.