Research On Resource Scheduling Algorithm Of Satellite Communication System

Satellite communication systems are capable of providing information interaction service for the ground terminal users by employing artificial satellites to transmit and receive.Because of their wide coverage,large capacity,robust performance and other advantages,satellite communication systems have attracted considerable attentions from the academia and industry in recent years.In order to meet the application requirements of users and improve the data transmission,task scheduling and overall performance of the system,it is necessary to design association selection and resource scheduling strategies for satellite communication systems.This thesis studies the joint association selection and resource scheduling algorithm of satellite communication systems.The main contents are as follows:Based on the overview of architecture and characteristics of current satellite communication system,this thesis introduces the key problems of satellite communication systems,summarizes the algorithms of association selection,task scheduling,joint task scheduling and resource allocation in satellite communication systems,and emphasizes the importance of joint task scheduling and resource allocation algorithm.Stressing the data transmission requirements of Internet of things(Io T)gateway in satellite communication systems,the problem of joint gateway association and resource scheduling are studied.Considering the constraints of satellite physical links and capacity resources,the joint user association and resource scheduling problem are formulated to minimize the transmission delay.As the optimization problem is a non deterministic polynomial(NP)hard problem,it is difficult to solve by traditional optimization methods.In order to solve the above problem,this thesis first considers the single gateway scenario,proposes a gateway association and data scheduling strategy based on greedy algorithm,and then extends the solution to the multi-gateway scenario,proposes a joint gateway association and data scheduling algorithm based on transmission priority.Finally,the effectiveness of the proposed algorithm is verified by MATLAB simulation.Stressing the problem of association selection,task scheduling and task offloading in satellite communication systems,this thesis models the problem of joint association selection,task scheduling and task offloading to maximize system utility function,under the constraints on task transmission requirements,link availability and ground computing resources.As the optimization problem is NP hard,this thesis decomposes the optimization problem into inter-satellite task scheduling subproblem and satellite-ground task offloading subproblem,and solves two subproblems based on genetic algorithm and tabu search algorithm,respectively,so as to obtain joint association selection,task scheduling and task unloading strategy.Simulation results show that the proposed algorithm can improve the system performance and achieve efficient task transmission.