SAR Echo Simulation And Image Modeling Of Typical Scenario

More and more information began to emerge in the SAR echo.SAR echo is the mapping of scattering rate of scene and terrain,which reflect the interaction between electromagnetic wave and ground objects such as ocean and grassland.According to SAR echo simulation technology,process and mechanism of interaction between electromagnetic wave and complex scenes can be researched.Also,it can establish the corresponding forward model and provide data source for the field of remote sensing classification,identification and parameter inversion synchronously.This paper presents SAR echo simulation and image modeling in typical complex scene.The main work of this paper is as follows:(1)Complex scene geometry modeling method and the parameter characteristics of the medium different scenarios were studied.Geometric models which include grassland containing tanks and time-evolving sea surface were set up in this paper.Bounce ray method based on the calculation method of the high frequency electromagnetic scattering was used for complex scenarios echo simulation.(2)ISAR image of both real target and camouflage target were first modeled through FEKO software.Then the differences in echo scattering and SAR images caused by structural differences between the two targets were studied.In this paper,a target feature extraction algorithm combining gray and texture is presented,and the algorithm was used to tell apart real targets and camouflage targets in Lynx SAR image.The simulation results show the effectiveness of the target feature extraction algorithm and provide a new way for the identification of military passive camouflage targets.(3)Based on SBR,the method of high frequency electromagnetic scattering is used to simulate grassland scene containing tanks and time-evolving sea surface.First of all,according to dynamic water scence,IPIX radar measured data was used to study the modulation characteristic of sea clutter.Secondly,a complete set of geometry modeling and dynamic sea echo simulation process was established,which is used to generate time-evolving sea surface geometric model and simulate SAR echo.Finally,the data table structure of dynamic sea surface echo simulation is designed for the complete preservation of geometric model parameters,electromagnetic scattering calculation parameters and echo data.(4)Based on Visual c + + visualization integrated development tools,using matlab GUI interface for the application software design,this paper designed and developed a scenario for dynamic sea echo simulation software.Matlab parallel computing module was used to accelerate electromagnetic scattering computing for the situation of multiple perspectives.The software can generate time-evolving sea surface in continuous time,which provide simulation echo data for the analysis of sea clutter and radar target detection,recognition.The simulation results to one dimensional range image and two-dimensional SAR image were displayed.This paper is devoted to SAR echo simulation and image modeling in complex scenarios.Firstly,radar image modeling is carried out for the authenticity and fake targets in a typical military battlefield and the differences of scattering mechanism between the authenticity and fake targets are analyzed.Also,mage modeling provides the basis for target recognition of SAR images.Secondly,SBR-based high frequency electromagnetic calculation method is used to simulate the echoes of two typical complex scenarios——grass scenario of the compound tank and time-varying scenario of the ocean surface.The validity of simulation results are analyzed qualitatively and quantitatively.Finally,this paper develops an application software of echo simulation for dynamic ocean surface scenarios.Research results of this paper are helpful to study the electromagnetic scattering characteristics of targets,SAR target detection and recognition under complex background.