Rapid Simulation Of Echo Data Of Space Micro-moving Target And Research On ISAR Imaging Technology

In modern ballistic missile defense systems,in order to improve the survivability and effective penetration probability of mid-range ballistic targets,the front end is usually equipped with attitude control equipment,which aims to stabilize the flight attitude by controlling the target's spin.However,due to the horizontal interference of group targets such as surrounding bait,complex micro-motion forms such as precession or nutation often occur,which will challenge the echo acquisition and inverse synthetic aperture radar(ISAR)imaging research of the mid-course ballistic micro-motion targets.Based on the analysis of traditional micro-moving target dynamic echo acquisition methods,this paper proposes the rotational symmetry characteristics of the mid-range ballistic target,and establishes mathematical models that conform to various types of micro-motion forms to achieve the fast and accurate dynamic echo data of the mid-course ballistic micro-motion target,which fully overcomes the limitations of traditional methods in ensuring data accuracy and obtaining mixed target echoes.At the same time,from the perspective of expanding the application,this article conducts research on the ISAR imaging of micro-motion targets,and by analyzing its radar echo modulation characteristics,successively introduces the imaging methods of micro-motion targets based on the inverse Radon transform and the sparse representation theory sparseness for the missing part of the radar signal.Finally,the correctness and effectiveness of the theoretical method are verified in combination with specific experimental simulation results.The main work arrangement of this article is as follows:(1)First,the basic electromagnetic scattering theory for the rotationally symmetric target is introduced.Then the main content of the classical ISAR imaging theory is explained in detail.Finally,the possible problems of the ISAR imaging of the missile target are pointed out.(2)First,it starts with the traditional method of acquiring dynamic echoes of the micro-motion target,and briefly describes its specific implementation process and corresponding limitation analysis.Second,based on the rotational symmetry characteristic of the mid-course ballistic target and the domain decomposition method based on the equivalence principle algorithm,simulation of the dynamic echo data of the mid-course ballistic micro-motion group targets can be achieved fast and accurately by performing mathematical modeling and analyzing on various types of complex micro-motion targets.Finally,by verifying the dynamic echo data under various complex motion scenarios,the feasibility and advantages of the method are explained.(3)Study the basic theory of radar echo modulation characteristics and micro-Doppler effect of micro-motion targets.Aiming at the limitation of the specific micro-motion parameters of the traditional instantaneous imaging methods of micro-motion targets,the research of imaging methods of micro-motion targets based on inverse Radon transform is conducted,the validity of the method is verified by simulation examples.Considering the problem of missing radar data in the actual detection environment,the radar signal sparse representation model was established to complete the research on the high-resolution ISAR imaging theory of micro-motion targets based on compressed sensing theory and the simulation verification of examples.