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Radarsat-2 offers a variety of new modes and capabilities. We present results from rigorous application of geometric and radiometric calibration to backscatter values, enabling comparisons between different modes. First, the system's a priori geometric accuracy was tested (tiepoint free) by comparing the measured positions of corner reflectors in ultrafine images with predicted locations calculated based on the satellite state vectors and radar timing annotations. Second, the geometric accuracy of the dualpol ScanSAR SCNB mode was tested by correlating each backscatter image to a radar image simulation calculated using the same product annotations. Third, the radar image simulation was used to normalize the backscatter values in both polarisations, generating terrain-flattened gamma nought values that were then terrain geocoded. Fourth, the available ascending and descending SCNB image pair was overlaid with and without such radiometric terrain correction applied. The advantages gained by using terrainflattened gamma nought are discussed. Abstract. Radarsat-2 offers a variety of new modes and capabilities. We present results from rigorous application of geometric and radiometric calibration to backscatter values, enabling comparisons between different modes. First, the system's a priori geometric accuracy was tested (tiepoint free) by comparing the measured positions of corner reflectors in ultrafine images with predicted locations calculated based on the satellite state vectors and radar timing annotations. Second, the geometric accuracy of the dual-pol ScanSAR SCNB mode was tested by correlating each backscatter image to a radar image simulation calculated using the same product annotations. Third, the radar image simulation was used to normalize the backscatter values in both polarisations, generating terrain-flattened gamma nought values that were then terrain geocoded. Fourth, the available ascending and descending SCNB image pair was overlaid with and without such radiometric terrain correction applied. The advantages gained by using terrain-flattened gamma nought are discussed.Résumé. RADARSAT-2 offre une variété de nouveaux modes et fonctionnalités. Nous présentons les résultats obtenus par l'application rigoureuse de la calibration géométrique et radiométrique sur les valeurs de rétrodiffusion, permettant de comparer les différents modes. Premièrement, la précision géométrique a priori du système est testée (sans points de soutien) en comparant les positions de réflecteurs trièdres mesurées sur les images ultra-fines avec les positions prévues, ces dernières étant calculées à partir des annotations contenant les vecteurs d'état du satellite ainsi que les paramètres temporaux du radar. Deuxièmement, la précision géométrique du mode ScanSAR en polarisation double (appelé SNCB) est testée en corrélant chaque image de rétrodiffusion avec une image radar simulée, générée en utilisant les vecteurs d'état et les paramètres temporaux extraits des annotations en combinaison avec un MNT. Troisièmement, ...

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The increasing availability of fully polarimetric SAR data provides a large potential for the assessment of biophysical forest parameters. Aiming at an inversion of polarimetric parameters into forest parameters, this study shows the sensitivity of polarimetric decomposition theorems (Pauli-and H-/α decompositions) to biophysical forest parameters, especially forest density. Effects of non-biophysical parameters on the estimation of decomposition parameters are also shown. The investigations were carried out on fully polarimetric data at L-band (1.3 GHz) and P-band (350 MHz) acquired in 2003 in a preAlpine region in Switzerland with the German E-SAR (Experimental SAR) platform.

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