Research On Resource Scheduling Model And Algorithm For Satellite-Ground Time Synchronization Of Beidou Satellite Navigation System

With the official provision of services by the Beidou-3 satellite navigation system,higher requirements are placed on satellite navigation performance.Star-time synchronization is the basis of satellite navigation system operation,and is the main factor affecting system positioning and timing accuracy.It plays an indispensable role in the operation of Beidou No.3.Based on the purpose of solving the practical problems of time-synchronous resource scheduling of Beidou navigation system under different users' needs,this thesis is based on the development of new theories and methods,mainly researching the framework of the optimal scheduling of satellite-based time and ground resources,and the demand for specific applications.Star-time time optimization scheduling problem,star-time time synchronization task planning problem for complex task requirements,and based on the data of Beidou No.3 navigation system for instance verification.The main research results of the full text are as follows.(1)The framework for solving the problem of optimal scheduling of ground resources is constructed.In view of the operational characteristics of the Beidou global navigation system and the actual user needs,the complexity and difficulty of the problem are analyzed.Aiming at the commonality and individualized characteristics of the problems under different requirements,a solution framework design based on the phased solution is proposed.The unified modeling rules are formulated,resource modeling,constraint modeling and time window modeling are carried out.Target modeling and specific constraint modeling are added according to different requirements,and the overall scheduling framework of the same time and ground resources is proposed.(2)Based on the specific application requirements,a genetic algorithm based on decomposition integration is proposed.The problem of satellite resource scheduling for specific application needs is aimed at the overall benefit of the task.The paper considers the arc length characteristics of strong application requirements and weak application requirements,and applies traditional scheduling algorithm,arc length based heuristic algorithm and decomposition integrated genetic algorithm to solve the problem,which can be applied and engineering practice.(3)Aiming at the requirements of complex tasks,a multi-objective evolutionary method solving framework based on sequence insertion is proposed.Considering the overall requirements of the system in the middle and late stages of construction,a multi-objective optimization problem model for system performance is established.A heuristic algorithm based on dynamic priority is proposed,and a multi-objective evolution method solving framework based on sequence insertion is established.The initial task set is generated by the heuristic method,and the selected multi-objective solving algorithm is embedded,and the final task set is generated by the method of sequence insertion,taking into account the solution quality and the solution efficiency.In the case-based verification based on Beidou navigation system,the heuristic-based multi-objective solution framework has achieved a better solution.The system optimization effect is much better than the heuristic method,and can be applied by selecting appropriate multi-objective algorithm and window processing method.And engineering practice is more suitable for system operation.