Research On Resource Scheduling In LEO Satellite System

To deal with the bottlenecks of the development of ground communication network in recent years,the scope of coverage is limited and the influence of the terrain.The satellite communication system,which is regarded as the development direction of the future communication industry,has got great attention and research.But with the progress of society and the development of communication technology,the demand of people for the quality of communication gets also higher and higher.The following problem is how to make better use of limited satellite resources to provide more users with better communication experience.For this reason,we need to design effective resource scheduling strategy to allocate resources on the satellite rationally.Combined with the characteristics of burst traffic in the network and the change of channel condition with frequency,we allocate the resources on the satellite more accurately and distribute them to the user terminals more quickly.In this paper,the project that we will research is resource scheduling in LEO satellite system.At first,we expound the research background and significance of this project,introduce the structure of the low orbit satellite communication system and the key technologies of satellite communications in detail,including position management,handover,resource management and so on.Then We compare multiple access technologies and introduce the network planning of the MF-TDMA multiple access technology in detail.After introducing several classical MF-TDMA resource allocation algorithms,this paper proposes a resource allocation algorithm based on QoE.Finally,we design a two-level resource scheduling strategy and do a system-level simulation.In this paper,a MF-TDMA resource scheduling algorithm based on QoE is designed.We introduce the concept of the quality of user experience in the premise of the maximization of resource allocation rate.First of all,this paper designs four kinds of user experience quality models based on the features of each user station and the characteristics of satellite communication.Then the reason is analyzed that the condition of different channel in the system is different due to the influence of the rain attenuation.A bipartite graph model is built based on the allocation of slot in MF-TDMA carrier.Based on the characteristics of resource allocation in this system,the optimal resource allocation scheme based on the QoE maximum criterion is obtained by the Hungarian algorithm many times.Finally,the simulation results show that the proposed algorithm not only guarantees resource utilization,but also improves the quality of user experience.A new resource scheduling algorithm is proposed in the satellite system due to the delay problems of the long distance transmission.We introduce the user station into the original satellite system,that manager the resource allocation of the group of users.In order to reduce the process of interaction long distance,so as to reduce the delay.First of all,we make simulation experiment of the resource management strategies for the gateway station and subscriber station.Then we make a system-level simulation by the OPNET simulation platform to verify the results and introduce the OPNET simulation platform to show our entire system.