Target Tracking,Scheduling And Effectiveness Evaluation Method Of LEO Constellation Early Warning System

As an important part of the complete ballistic defense system,the space-based early warning system can track and monitor the ballistic missiles during the full trajectory,and has become the development focus of defense system for the most military powers.Based on the space-based LEO constellation early warning system,target tracking by satellite observation,scheduling of constellation resources and effectiveness evaluation of LEO constellation early warning system were studied.The main results achieved in this dissertation are summarized as follows.Based on only-angle observation of satellite,the“Current”statistical model filtering algorithm which is adaptive by Yule-Walker method is proposed to track the target.Based on UKF,the method which can adaptively adjust parameters of Current statistical model by Yule-Walker method is introduced.The simulation results show that target state estimation error could converge to 125m,8m/s,0.4m/s~2respectively.Furthermore,the target tracking observability based on Posterior Cramer-Rao Lower Bound is derived.The influence of satellite number and measurement noise on tracking performance is analyzed through simulation.The framework of multi-target tracking periodic-rolling scheduling for LEO constellation is constructed,then,the Genetic Algorithm and heuristic rule scheduling algorithm are designed to schedule the constellation resource.Considering the predictability of the target trajectory on the coast phase and the complex correspondence between satellite and tracking targets,a task compositing of the multi-target tracking method is designed to simplify relationships between tasks and satellite,further the periodic-rolling scheduling framework is constructed to schedule satellite resource.On this basis,the satellite resource scheduling model based on genetic algorithm and heuristic rule scheduling method are built.The simulation results show that target tracking accuracy and mission revenue rate are both more than 90%,but the satellite switching rate is up to 44.74%by the strategy of GA.For heuristic rule scheduling method,while ensuring the tracking accuracy,it reduces the switching rate to about 13%which improves the satellite work efficiency.A series of indexes about the LEO constellation early warning system effectiveness evaluation were proposed.In addition,a comprehensive evaluation method based on fuzzy theory was designed.From the perspectives of warning mission,satellite use and data fusion,the effectiveness evaluation index is constructed while ensuring the weight of each index by analytic hierarchy process.The comprehensive evaluation model based on fuzzy theory was composed by fuzzy index using membership function,the achievement process was introduced specifically.In the end,the scheduling strategy solved by GA and heuristic rule scheduling respectively is evaluated by the fuzzy theory to help decision makers.