Model And Method Of Periodic Observation Task Scheduling For Networked Satellites

With the application of satellite remote sensing data more and more widely,countries around the world have continuously increased their research investment in space exploration,so the satellite platform and load technology has been rapid development.With the deepening of the demand for remote sensing data in people's production and life,it is necessary to periodically obtain the latest situation of certain ground targets.This requires the satellite to periodically observe the target in order to achieve the regular refresh of the target situation.The earth observation satellites are mostly low earth orbit satellites.Due to the limitation of satellite orbit,it is difficult for single satellite to complete this kind of demand.It is necessary for multiple satellites to form a networked satellite system,which can be used to accomplish periodic observation task.This puts forward higher requirements for satellite observation task scheduling.Most of existing satellite observation task scheduling model assumes that the target just one or the fixed number of observation,observation task to complete,it is difficult to directly applied to the networked satellites periodic observation task scheduling problem.This paper studies the scheduling of the periodic observation task of the networked satellites,and the main results are as follows:1)A multi-objective solution model for networked satellite periodic observation task scheduling is established.Based on the analysis of the characteristics of the networked satellites periodic observation task scheduling,the main constraints of the network satellites periodic observation were extracted and the constraint satisfaction model was established.Two optimization objective functions,such as the weight degree of timeout and the degree of resource consumption,are determined.2)A satellite periodic observation scheduling algorithm based on MOEA/D is proposed.Based on the multi-objective solution model for networked satellite periodic observation task scheduling,the framework of MOEA / D algorithm is selected,the genetic operators are designed,the constraint checking and correction operators are introduced,and a satellite periodic observation scheduling algorithm based on MOEA/D is proposed.In order to verify the effectiveness of the algorithm,a new algorithm based on greedy strategy is proposed for the networked satellites periodic observation task scheduling algorithm.The feasibility and effectiveness of the proposed algorithm are verified.3)An improved MOEA/D algorithm combined with heuristic local search is proposed for networked satellites periodic observation task scheduling.On the basis of the satellite periodic observation scheduling algorithm based on MOEA/D,introducing the heuristic local search operator,enhancement the local search ability of the algorithm on two objective functions,a satellite periodic observation scheduling algorithm based on MOEA/D and heuristic local search is proposed.Simulation results show that the optimized performance is better than the satellite periodic observation scheduling algorithm based on MOEA/D,but it takes more time to calculate.4)Prototype system for task scheduling of networked satellites.Based on the research content,an experimental system for practical application is designed and implemented.