Research On Interferometric Method Of Target For Video Synthetic Aperture Radar

With the advancement of science and technology and the improvement of device manufacturing processes,synthetic aperture radar(SAR)technology has matured.Furthermore,video SAR technology has begun to appear in people's field of vision,attracting more and more attention and research.Video SAR has the unique advantages of high frame rate as well as high resolution.Terahertz video SAR not only has the advantages of video SAR,but also has the characteristics of low latency.It has unique advantages in some real-time scenarios.This paper mainly combines the high frame rate imaging and interferometry technology of video SAR,and conducts research on the method of video SAR interferometry.The main work is as follows:(1)Propose a circular spotlight interferometry model suitable for video SAR.First,analyze the traditional interferometric synthetic aperture radar(InSAR)measurement model,and derive the elevation inversion formula.Then according to the imaging mode of video SAR to find the main difference between traditional InSAR and video SAR interferometry.The spotlight mode interferometry model is established,moreover,the target height inversion formula is derived based on the spotlight interferometry model,and interferometry suitable for video SAR Process.(2)Research on the retrieval of the height information of the video SAR target.First,according to the height inversion formula of the video SAR interferometry system.The main factors affecting the accuracy of the height inversion are theoretically analyzed,and the main source of the video SAR interferometric phase error is deduced and verified by simulation.Secondly,according to the video SAR interferometry process.The key steps in the video SAR interferometry process are simulated and verified.Then,theoretically analyze the limitations of traditional registration methods and the reasons for the distortion of the Digital Elevation Model(DEM).Next,give the DEM distortion correction method,and finally get the terrain information of the target area.Finally,according to the video SAR interferometric measurement process,a method of threedimensional target positioning is proposed.Besides,the accuracy of the threedimensional positioning is verified through inertial navigation data.(3)Multi-aperture data fusion method for video SAR interferometry.First,according to the advantages of video SAR high frame rate imaging,a data screening method based on confidence interval is proposed based on video SAR multi-aperture data.Then theoretically analyze the feasibility of interferometric measurement of adjacent subaperture images,and give the critical conditions and interferometric flow of adjacent subaperture interferometry.Finally,multiple sets of elevation inversion results are used to improve the accuracy of elevation inversion through data fusion,which is verified by simulation experiments.