Single Satellite Early Warning Algorithm Based On Prior Information Fusion And Error Analysis

Space-based early warning of high orbit satellites can use infrared sensors for the ground and space targets detection and tracking,providing information support for the perception of the battlefield situation,which belongs to passive detection.Spaceborne sensors can detect infrared radiation from boost-phase missile plume of high temperature,so as to find missile launchers and estimate its tactical parameters,such as forecasting impact position and heading of missile,so that missile early warning is possible.In target discovery time and surveillance breadth,space-based early warning in high orbit has obvious advantages than low orbit and ground-based radar.It is the urgent need to make a research of high orbit space-based early warning system.One of the core issues of high orbit space-based early warning is the ballistic missile parameter estimation in boost phase.In boost phase of missile,high orbit spaceborne sensor can only obtain line of sight(LOS)measurements of plume radiation,that is,in single satellite situation measurements information confines to two dimensions,belonging to the incomplete observations.In certain star-missile relative observation geometry,the estimation is morbidity with poor estimation accuracy.To solve this problem,we can build a stronger dynamical model providing constraints.Another way is to establish a prior information fusion of early warning estimation to provide third dimensional information.In this dissertation,the main work involves different types of early warning prior information fusion,prior information error analysis and estimation bias suppression.The main contributions are as follows:Firstly,different types of early warning prior information are classified systematically,and prior information use patterns are discussed.On this basis,an early warning prior information fusion for ballistic parameters estimation algorithm based on maximum a posteriori is constructed.After discussion and giving the prior and posterior distribution,an equivalent maximum likelihood estimation in penalty function form is proposed.In a typical star-missile relative observation geometry space,single factor error propagation for prior information and posterior sensitivity is analysed.Secondly,on the basis of analysis of the missile movement law and motion model error,an algorithm of early warning for single satellite based on missile optimal trajectory inclination angle constraint is proposed.Meanwhile,according to the algorithm simulation results that estimation deviation with star-missile relative observation geometry,an algorithm for deviation suppression is given.