Research On Topology And Routing Planning Methods In Resource Constrained Satellite Networks

In recent years,with the increase in the demand for space communication,various aerospace powers have set off an upsurge in satellite network construction and key technology research.Satellite network links have the characteristics of long delay,intermittent connection,and link attributes change with time,so it cannot be characterized by the static graph characterization method of terrestrial networks.The fundamental reason is that the network representation method based on static graph separates the relationship between network resources in the time dimension.On the other hand,due to the limited energy carried by satellite nodes and the difficulty of fuel supply,their power consumption must be controlled to prolong their service life.Therefore,the number of transceiver loads of satellite nodes and the transmission rate of inter-satellite links will be limited.It brings new challenges to the topology and routing planning of satellite networks.Based on this,aiming at the constraints of time-varying and limited resources of satellite networks,this paper studies the joint planning algorithm of topology and routing aiming at the shortest delay,facing the delay guarantee requirements of services.The main research work and innovative achievements are as follows :This paper summarizes the research status of satellite network technology at home and abroad;several typical resource constrained satellite network topology planning methods are introduced,and their advantages and limitations are pointed out;on this basis,the research objectives of this paper are introduced,and the challenges it faces are analyzed emphatically.A topology and routing joint planning algorithm is proposed,which aims to meet the delay guarantee requirements of space services,and can construct a shortest end-to-end delay for services under the constraints of time-varying satellite networks and single transceivers.transmission path.Firstly,a time-varying graph-based characterization method for resourceconstrained satellite networks is proposed,which can accurately characterize the node transmission rate constraints,single-transceiver constraints,and topology time-varying characteristics in resource-constrained satellite networks.Secondly,on this basis,a timevarying graph-based topology and routing joint planning algorithm is designed to construct a transmission path with the shortest end-to-end delay for services as needed,and topology connection planning is carried out according to the constructed path.Finally,the proposed algorithm is simulated by Matlab simulation software.The simulation results show that the algorithm has higher service completion rate and lower average end-to-end delay than the routing algorithm based on the minimum number of hops.A routing protocol suitable for resource-constrained satellite network is designed,and a simulation and verification platform for resource-constrained satellite network routing protocol is built to verify the efficiency of the protocol.According to the characteristics of intermittent connection of satellite network links and predictable topology,and based on the proposed topology and routing joint planning algorithm,a routing protocol for resourceconstrained satellite network is designed.Based on the open shortest path first routing protocol,the designed routing protocol adds predictive topology discovery,time-varying routing calculation and store-host-forward power mechanism.At the same time,a hardwarein-the-loop simulation and verification platform is built.By simulating the characteristics of the space link,the functional modules of the protocol are tested,and the effectiveness of the resource-constrained satellite network routing protocol in the space environment is preliminarily verified.