Research On Multi-Satellite TT&C Scheduling Models And Algorithms

The main objectives of Multi-Satellite TT&C(track, telemetry & control) Scheduling Problem(MuSTSP)are to maximize the satellites'design efficacy through TT&C resource scheduling and to support the high-level decision-making process of TT&C system. MuSTSP is a kind of NP problems with complex requirements and constraints. It also has some special characteristics, such as hard time window constraints. It is of great theoretical importance to research MuSTSP. It can also provide a great guidance to utility efficiency promotion of the TT&C resources, the TT&C requirement satisfaction of satellites and the more effective satellite efficacy implementation. As the research subject of this thesis, some critical issues of MuSTSP are researched in this thesis: including the modeling methods, evaluation indices and evaluation methods, scheduling algorithms and applications. The main work and contributions of this thesis are as follows:In research of modeling. The TT&C requirement and the TT&C task are formally described and the requirement input criteria are given. Then the CSOP model of MuSTSP is proposed by analyzing the constraints and objectives of MuSTSP systemically. Finally the ontology framework is built by abstracting the basic elements of MuSTSP, such as TT&C requirement,scheduling objective,TT&C resource,TT&C service and etc. This framework can depict the domain knowledge very well and can also lay the groundwork of the reuse & interaction of model and datum.In research of indices system and evaluation methods. The inherent evaluation indices system based on configuration and the user-oriented indices system are proposed respectively, and the computation methods are also researched. Some new concepts are proposed, such as RESOURSE CONFLICTION , RESOURCE SUPERPOSITION and RESOURCE REDUNDENT, which can facilitate the evaluation of system configuration. By applying the indices system to guide the TT&C scheduling and resource configuring process, the feasibility of the indices is proved. The indices system of this thesis can lay the evaluation groundwork of TT&C configuration, final schedule and scheduling algorithms. In research of scheduling algorithms. A two-stage hybrid scheduling algorithm is designed for solving MuSTSP.(1) The concept of Task Synthesis Scheduling Priority (TSP) is defined. And by analyzing the effect factors of MuSTSP scheduling and the impacts of requirements satisfaction, a requirement-orient TSP (ROTSP) algorithm is studied. The TSP change is dynamic, which ensures the more rational results.(2) By considering the MuSTSP as a kind of K out of N constraint combination scheduling problem,a Multi-dimensional Parameter Character Coding Method(MDPCCM) is designed, and the corresponding GA operators, neighborhood and taboo shifting operator of MDPCCM for MuSTSP are also researched. Then some heuristic rules are introduced and an Oriented GATS(OGATS) algorithm of MuSTSP is designed. Then the theory of Markov chain is used to analyze the convergence of this GATS algorithm. Finally, the performance and applicability of different algorithms is analyzed by simulations. If this two-stage hybrid scheduling algorithm is properly used according the scale and applicability, then it can satisfy different time and precision requirement of solving MuSTSP.In research of applications. On the basis of theoretical research, a Multi-Satellite TT&C Scheduling and Evaluation System(MuSTSES)is developed, which provides a useful tool for engineering applications and further research. The application method of TT&C scheduling technology is studied by illustrating the optimization process of a specific scenario. The result shows the validity of this thesis's research.