SAR Slow Moving Target Imaging Based On Phase Retrieval

As a novel imaging radar with all-weather and full-time characteristics, synthetic aperture radar(SAR) has been widely used in military confrontation and civil using. Moving targets imaging is the process that using the effective detecting information to refocus the blur image, which has a important strategic implications to radar system. Then it has been crucial to solve the blur imaging obtained by target’s moving because of the importance of acquiring the correct information of the imaging scene.For this problem, the moving target imaging and simulation based on phase retrieval has been studied in this thesis. The main content and innovation of this paper is as follows:Firstly, explain the basic system model of SAR and the imaging mechanism and imaging algorithm in SAR, then analysis the imaging feature of the moving target in detail and following the simulation verification by the computer.Secondly, Several phase retrieval methods at present of which widely used in optics imaging are introduced in details; After studying deeply of these methods, a new SAR imaging method with sparse scene is proposed which based on phase retrieval. Then through computer simulation of the sparse point and area targets, its validity is proved.Finally, on the basis of the two-dimensional frequency domain analysis of SAR moving target and the stationary target imaging by using phase retrieval method, a new refocusing method of sparse moving target which based on phase retrieval is proposed. The method explains the two-dimensional frequency domain features of moving targets and gives a flow chart of the imaging processing. Then, through computer simulation of simulated data, the theoretical analysis and rightness of this method is realized and verified.