Research On Key Technology Of Hypersonic Target Location Based On Airborne Heterogeneous Sensors Of UAV

In recent years,the frequent flight tests of hypersonic vehicles by military powers,represented by the United States,have made hypersonic vehicles gradually come into view.Its great speed advantage make it very difficult for the Air Defense Early-warning System to effectively alert it,which poses a serious challenge to the national air defense system.In order to improve the defense capability for hypersonic target and strengthen the defense force,this paper mainly studied the high-precision positioning and tracking technology for the hypersonic target,basing unmanned aerial vehicle as the detection platform.Firstly,the paper analyzes the motion characteristics of hypersonic vehicle and its tracking characteristics in different flight stages.Aiming at the short warning time caused by its great flight speed,the tracking performance of different tracking platforms for hypersonic targets are compared and analyzed,and a hypersonic target location scheme based on the heterogeneous sensors of UAV platform is designed,combining with the tracking characteristics of hypersonic vehicle in each flight segment.A target localization method based on angle and distance measurement is studied and the influence of different error sources for the target location accuracy is simulated and analyzed.The results show that the attitude error of UAV and measurement error of target are the main factors affecting target positioning accuracy,which lays a theoretical foundation for improving the positioning accuracy of the target subsequently.Secondly,this paper studies the target motion models conforming to different flight characteristics of hypersonic vehicle and the target tracking filtering method for nonlinear systems.Aiming at the problem that the sensor detection accuracy has a great influence on the hypersonic target positioning accuracy,the heterogeneous sensor measurement in UAV is extended and fused,a UKF filter algorithm is designed based on the fusion information.Combining with the target motion model with different motion characteristics of hypersonic vehicle,the performance of the algorithm is verified by simulation.The simulation results show that the improved UKF filtering algorithm can effectively improve the accuracy of target location compared with the traditional UKF filtering algorithm.In order to deal with the situation that UAV can only obtain angle measurement information or ranging information,this paper studied the least square target location method based on angle measurement information and the least square target location method based on ranging information.The influence of different relative positions between multiple UAVs and targets on target positioning accuracy is simulated and analyzed.Finally,this paper builds the UAV target positioning simulation platform,including UAV navigation information simulation subsystem,track simulation subsystem,airborne sensor observation simulation subsystem and target positioning system,which provides a good experimental platform for the verification of algorithm.