Super-resolution Persistent Scatterer Interferometry

D-In SAR and time-series In SAR are one of the most successful technologies in the filed of SAR,which have been widely used in many applications including volcanic terrain deformation monitoring,landslide deformation monitoring,building deformation monitoring.Compared with D-In SAR,time-series In SAR reduces the decorrelation and improve the accuracy.Based on previous studies,this paper proposes a new time-series In SAR chain-Super Resolution Persistent Scatterer Interferometry,SR-PSI.In this study,we focus on SR-PSI.We set the main objective of this research as to construct a full chain of SR-PSI by integrating the super-resolution reprocessing algorithms into PSI,and to validate the effectiveness of SR-PSI through both simulation and real-life SAR data.Our contributions are presented as follows.1.We analyze the problems of current time-series In SAR algorithms.In order to improve the density of PS points in PSI,we propose the workflow of SR-PSI,which integrates spectral-estimation-based SAR reprocessing algorithms into PSI.2.We study the theory of super-resolution reprocessing algorithms.Besides,we analyze several aspects in the implementation,and the fast algorithms.We also study the super-resolution reprocessing of TOPS data.3.In order to solve the problem the diagonal-loading based robust Capon algorithm may aggravate the edge effect,we propose a revised and robust Capon algorithm.The results of Terra SAR-X show that the algorithm can effectively reduce the edge effect of the reprocessed SAR image.4.The feature of adaptive resolution for the reprocessed SAR images causes the tradition PSC selection method can not be applied directly.We propose the peak-detection based PSC selection method,and present the full chain of SR-PSI.In order to analyze the performance of SR-PSI,we studied its evaluation workflow,and further carried out experimental verification based on simulation data and real-life data(Terra SAR-X,Sentinel 1 TOPS data).Both results of simulation data and real-life data show that SRPSI prevails the traditional PSI.The single-epoch Capon algorithm provides the best results in the context of PSI.We compare the the deformation rate,height,and standard deviation of PS extracted from real data and confirm that SR-PSI can preserve the phase quality as the traditional PSI.SR-PSI can increase the density of PS by 30%-50% than the traditional PSI.5.In order to improve the efficiency of SR-PSI,we propose to combine the SR-PSI and the traditional PSI by identification of homogeneous areas.We first derive the threshold of the coefficient of variation at different significance levels,and then analyzed the workflow of the combination processing.The experimental results of Terra SAR-X real data show that when the coefficient of variation threshold is set to 0.75,the combined processing algorithm can increase the PS density by 39% compared with the traditional PSI algorithm,and can improve efficiency of SR-PSI by 48%,which indicates that the joint processing method can maintain the effectiveness of SR-PSI and improve its efficiency.This paper analyzes the proposed SR-PSI technology in detail through the above research,and confirms its effectiveness through simulation data and real data experiments.Compared with traditional PSI,SR-PSI can increase the number of PS and reduce side lobe PS.We hope that the research in this paper can provide inspiration and help for related research,and be further applied to the engineering practice in deformation monitoring.