Research On Load Balancing Routing Strategy Based On Uncertainty Theory In Satellite Network

The satellite network is a space wireless network system with various types of satellites as network nodes and interconnected by inter-satellite links.Compared with terrestrial networks,satellite networks have characteristics of dynamic topology structure,long communication delay,and unbalanced data traffic.Based on the above characteristics,the routing strategy in terrestrial networks is not suitable for satellite networks.Thus,the routing strategy in satellite networks has been researched.However,the complex space environments lead to the uncertainty of link information in satellite networks,which causes the failure of satellite routing.In addition,the unbalanced spatial and temporal distribution of traffic lead to the imbalance of link traffic in satellite networks,which causes the network congestion.This thesis mainly researches on the load balancing routing strategy based on uncertainty theory in satellite networks from two aspects: the uncertainty of the link information and the imbalance of link traffic.The main works of this thesis are as follows:(1)To solve the uncertainty problem of link information caused by complex space environments in satellite networks,a routing strategy based on uncertain link information in satellite networks is proposed.Firstly,the uncertain link information is represented by the designed membership degree function.Secondly,the link comprehensive evaluation is obtained by the membership degree function of ideal point.Thirdly,the routing model for satellite networks is constructed based on the path comprehensive evaluation.Finally,the routing model is solved by the grey wolf optimization algorithm.Simulation results show that the proposed strategy can achieve efficient routing in complex space environments,and improve the performance on average delay,packet loss rate,and throughput.(2)To solve the imbalance problem of link traffic caused by the unbalanced spatial and temporal distribution of traffic in satellite networks,a multi-service routing strategy based on load balancing in satellite networks is proposed.Firstly,the space-time factor is designed by analyzing the characteristics of the unbalanced spatial and temporal distribution of link traffic.Secondly,the spacetime factor is introduced into the link comprehensive evaluation.Then,the route table is calculated by the link comprehensive evaluation.Finally,the multi-service transmission rules under different link states are designed by comprehensive consideration of link states.Simulation results show that the proposed strategy can achieve load balancing in complex space environments,and improve the performance on average delay,delay jitter,packet loss rate,and throughput.