Study On Permanent Scatterers Technique In Differential Synthetic Aperture Radar Interferometry

Permanent scatterers technique of differential synthetic aperture radar interferometry(PS-DInSAR technique) is a typical one used in long time series deformation retrieving. Different from the traditional differential synthetic aperture radar technique(DInSAR technique), PS-DInSAR technique is based on some special point targets, the permanent scatterers(PS points), which can maintain highly coherent in the interferometric images with big spatial and time baseline, to retrieve the deformation information. After some signal process, such as phase filtering and phase unwrapping, PS-DInSAR technique can precisely retrieve the deformation velocity, whose accuracy is already validated by some experiments. Nowadays, PS-DInSAR technique is widely using in disaster monitoring, surface deformation retrieving and city sedimentation controlling.This paper focus on several key issues in the PS-DInSAR technique and special attention is paid to research the PS candidates selection in small data set, the data processing method in satellite formation SAR system using PS-DInSAR technique, and the performance of PS-DInSAR technique. The relevant works have not only expanded the application of PS-DInSAR technique but also promoted the PS-DInSAR technique so that it can adjust to the practical and engineering application. The main works and innovations are listed as follows:Chapter II first introduces the theory of DInSAR and PS-DInSAR technique. Then, two typical procedures of PS-DInSAR technique are discussed and analyzed.Chapter III is dedicated to the selection of PS candidates using a small data set. We first analyzed the defects of the traditional PS candidate selection method using a small data set. And then, after analyzing the signal characteristic of PS, we presented a new selection method. At last, the value of the new method developed in this paper is validated via experiments.Chapter IV focuses on the data process method dedicated to binary satellite formation of SAR system using PS-DInSAR technique. The advantages in deformation detection of the binary satellite formation of SAR system are first discussed. Then, according to the data characteristics of binary satellite formation, we propose two data process methods of PS-DInSAR technique, which is dedicated to retrieve the deformation maps using the images of binary satellite formation of SAR system. Finally, the effectiveness of the two methods is verificated based on the simulation experiments.Chapter V studied the quality evaluation of the PS-DInSAR technique. According to the procedure of PS-DInSAR technique, we modeled the error sources of the deformation retrieved in PS-DInSAR technique. The Cramér–Rao Bounds of parameters in PS-DInSAR technique and its approximation method are then exploited. Finally, the simulation results verified the correctness of the work.