| Interferometric synthetic aperture radar(InSAR),as a means of obtaining digital elevation model(DEM)and other value-added products by using phase information of synthetic aperture radar(SAR),with its all-weather,all-time,and high-precision features,has an extremely wide range of app lication in topographic mapping,environmental protection,and military investigation.Since interferometric phase is an extremely important intermediate product in InSAR data processing,the phase filtering,which can remove noise,is a guarantee for subsequent acquisition of high-precision DEM products.With the continuous innovation of InSAR technology,phase-filtering processes are also faced with higher demands.This thesis will focus on high-efficiency and high-precision adaptive engineering filter process,of which the major contributions are as follows.1.Based on the research status and development trend of both InSAR systems and phase filtering at home and abroad,high-efficiency and high-precision engineering method is the focus of modern phase filter processing.The InSAR geometry principle,InSAR data processing flow and the effect of phase noise and phase statistics on the phase filtering are briefly introduced and analyzed respectively.2.The commonly used filtering evaluation indicators are summarized.After analyzing their characteristics,a comprehensive evaluation index is proposed.C hapter 3 also conducts the theoretical research on existing common filtering algorithms,followed by the analysis of their features and application scop e.Then,the algorithm was compared and analyzed by the processing of measured data and filtering evaluation indexes.3.Based on the theoretical research of each algorithm,the design idea of adaptive filter processing is proposed on filter parameters and filter algorithms.The intelligent setting of the phase noise standard deviation auxiliary filter window and the autonomous selection of filtering algorithms based on the scene characteristics are studied emphatically.Besides,a priori database is propo sed to assist the block adaptive filter processing to meet the requirements of fast real-time processing.Finally,the validity of the method is proved by the measured data.4.With the increase of data volume and the requirement of data processing automa tion,filtering engineering processing modules have been designed from several aspects,such as input/output interface,parameter setting classification,professional analysis system,high-efficiency program and error reporting system.The processing of measured data shows the application of filtering engineering. |
