SAR, SAR Polarimetry & Multitemporal SAR Statistical Description

(held in English) Nowadays, several spaceborne Polarimetric Synthetic Aperture Radar (PolSAR) systems are in operation: TerraSAR-X (X-Band), RADARSAT-2 (C-Band), Sentinel-1a&b (C-band dual polarimetric), ALOS-2 (L-band), SAOCOM (L-band), RCM (Cband) and Gaofen-3. Also, future missions as BIOMASS (P-band) or NISAR (L&S-bands) are designed to have polarimetric sensitivity. An accurate Polarimetric SAR (PolSAR) data interpretation and understanding, as well as the process of quantitative and qualitative bio- and geophysical information extraction, need, on the one hand, from a physical knowledge of the polarimetric scattering process and, on the other hand, the statistics and the elements of information theory that apply to PolSAR data. After an introduction to the description and the physical interpretation of PolSAR data, this presentation will introduce a detailed description PolSAR and multidimensional SAR data, as well as the description of the relevant elements of information theory for a complete understanding of PolSAR data. SAR and PolSAR systems are based on the use of coherent microwaves. This coherent nature is at the origin of the Speckle phenomena. Despite being a complete physical phenomena, the complexity of the scattering process in man-made and natural targets makes necessary to describe PolSAR data statistically, and then, to consider Speckle as a noise component. The first objective of this presentation is to stablish the connection between the physics and the statistics, and then, to introduce the concept of Speckle noise under the Gaussian scattering assumption. Following it, the statistical distributions that characterize SAR, PolSAR and multidimensional SAR data will be presented. At the same time, the state-of-the-art in Speckle noise filtering shall be also presented. Finally, advanced statistical concepts for the description of data texture and highly heterogeneous PolSAR data shall be also considered Presentation objectives: • What is polarimetry? • To know the concept of scattering polarimetry and the PolSAR data descriptors • To know the physical interpretation of PolSAR data • Description of the concept of deterministic and distributed targets • Description of speckle noise and the concept of Gaussian scattering • To know the statistical description of SAR data • To know the statistical description of PolSAR data • Describe the state-of-the-art of Speckle noise filtering • To know the statistical description of target decomposition theorems • Description of the concept of data texture • To know the statistical description of SAR and PolSAR texture data • Information extraction based on the use of higher order statistical moments and log-cumulants