Multi-mode ENVISAT ASAR interferometry: techniques and preliminary results

The paper focuses on the interferometric capabilities of current and future SAR systems, like ENVISAT, RADARSAT-2, etc. The authors introduce a technique to obtain interferometric surveys by combining two images, coming from any SAR mode, together with a digital elevation mode (DEM). The DEM is exploited during the interferogram generation to provide, at one time, effective noise removal and compensation for the topographic-dependent fringes. The final product is a 'differential' (topography-compensated) interferogram, to be used for monitoring over landslides, upswelling, etc. An innovative technique is also discussed to estimate local coherence maps, to be used for classification and change detection. Such a technique exploits windows whose shapes and sizes adapt locally to the target features, to attain at one time the highest resolution and the best statistical confidence. Finally, applications involving the various ENVISAT ASAR modes are discussed.