Design And Implementation Of Spaceborne Multimode SAR/InSAR/DInSAR Simulating And Processing Software

Spaceborne synthetic aperture radar(SAR)is an active microwave imaging radar with all-time and all-weather observation capability,which can obtain high-resolution images.Spaceborne interferometric synthetic aperture radar(In SAR)and spaceborne differential interferometric synthetic aperture radar(DIn SAR)are developed for new applications on the base of SAR technology.In SAR technology provides possibilities to extract digital elevation model(DEM),and the deformation of the Earth's surface can be accurately acquired by using DIn SAR technology.There is a great application prospects and research value for spaceborne SAR/In SAR/DIn SAR system in many fields,such as military reconnaissance,topographic mapping and disaster assessment.Moreover,spaceborne SAR/In SAR/DIn SAR system has many orbit modes and work modes which have their own advantages.System simulation,echo simulation and various processing algorithms for spaceborne SAR/In SAR/DIn SAR can not only give guidelines for allocating the satellite's reliability indexes and designing system schemes,but also provide the data support to study spaceborne SAR/In SAR/DIn SAR system for individuals and research institutes.Therefore,developing a spaceborne multimode SAR/In SAR/DIn SAR simulating and processing software is of very large scientific value and practical significance.This thesis developes spaceborne multimode SAR/In SAR/DIn SAR simulating and processing software on the basis of spaceborne SAR/In SAR/DIn SAR system theories.The software provides quick echo simulation for multimode spaceborne SAR/In SAR/DIn SAR system combining frequency domain echo simulation algorithm and parallel computing method,besides,it provides imaging algotithm for multimode echo data,interference algorithm to obtain digital elevation model,differential interference algorithm to obtain surface deformation.The primary work in this thesis are summarized as follows:1.The progresses of research on spaceborne SAR/In SAR/DIn SAR system and relevant simulating and processing software both in home and abroad are summarized,and the spaceborne SAR/In SAR/DIn SAR system theories are introduced.2.Based on the basic theory of software development,a software architecture pattern combined the layered model with the object-oriented model is introduced.The software is divided into the UI presentation layer,the business logic layer and the database access layer.UI presentation layer is responsible for the demonstration of software interface and the acquirement of system parameters.The business logic layer includes some function modules.The database access layer is mainly to access information from file systems and achieve interaction of data.3.A spaceborne multimode SAR/In SAR/DIn SAR simulating and processing software is designed and implemented based on Visual Studio 2010 development platform and Microsoft Foundation Classes(MFC).The software has a universality expansion on thack mode,work mode and antenna mode in the prototype of spaceborne strip-mode simulating and imaging function design.It includes five function modules,i.e.,echo simulation module,SAR imaging processing module,In SAR processing module,DIn SAR processing module and performance evaluation module.The universality design of the software includes imaging mode design and simulating with flexible beam pointing(spotlight/sliding-spotlight mode and mosaic mode)to satisfy the demand for high resolution mapping and the universality of track mode to suit different track mode like LEO,MEO and GEO.In order to improve the universality of antenna mode,the software expands parabolic antenna mode on the base of planar antenna and provides multiple antenna pattern input method.To realize the imaging processing for complex orbital configuration,the software adds Back-Projection algorithm to satisfy the imaging demand for different work mode.In consideration of application,the software realizes echo simulation function,algorithm processing function and performance evaluation function on In SAR system and DIn SAR system.In addition,The software realizes echo simulation for artificial target and area target to obtain more plentiful ground information and texture information.Due to the speed of the echo simulation is extremely slow,the parallel echo simulation module is designed based on Open MP parallel framework.Thus,the running time of echo simulation operation is greatly decreased without the loss of accuracy.4.Finally,the thesis sums up the main work and innovative research results as well as the shortcomings during the software development,and prospects for the future research work.