Preliminary Analysis of fully polarimetric air and spaceborne SAR Measurements for Security and Reconnaissance Purposes

摘要

This paper describes the analysis of fully polarimetric measurements acquired by the space-borne SAR-systems Radarsat 2 and TerraSAR-X with respect to the application on reconnaissance and security purposes. Firstly the analysis is carried out for single pixels by using the method of calculating SAR signatures in dependence on the orientation and ellipticity angle of the polarization ellipse. This method is applied to canonical scattering objects as well as to real measurements. Secondly, as a collective method for analyzing the types of scatterers in a measured image the entropy-alpha-method is used. The method is deployed to measurements from the JPL AIRSAR, DLR FSAR, Radarsat 2, and TerraSAR-X. The goal is to cover the different frequencies at L-, C-, and X-band as well as different spatial resolutions from 30m down to 0,25m. The results show that the methods are very well applicable. The application to real measurements demonstrates that the polarimetric effects are mainly dependent on frequency, spatial resolution and especially speckle or thermal noise. Proposals are given for upcoming analysis.