Rapid urban mapping using SAR/optical imagery & comparative study on the performance of multiparameter SAR data for operational urban areas extraction
Etude comparative sur la performance des données radar (SAR) multi-paramètres pour l'extraction opérationnelle des zones urbaines
Résumé
The advent of a new generation of synthetic aperture radar (SAR) satellites, such as Advanced SAR/Environmental Satellite (C-band), Phased Array Type L-band Synthetic Aperture Radar/Advanced Land Observing Satellite (L-band), and TerraSAR-X (X-band), offers advanced potentials for the detection of urban tissue. In this letter, we analyze and compare the performance of multiple types of SAR images in terms of band frequency, polarization, incidence angle, and spatial resolution for the purpose of operational urban areas delineation. As a reference for comparison, we use a proven method for extracting textural features based on a Gaussian Markov Random Field (GMRF) model. The results of urban areas delineation are quantitatively analyzed allowing performing intrasensor and intersensors comparisons. Sensitivity of the GMRF model with respect to texture window size and to spatial resolutions of SAR images is also investigated. Intrasensor comparison shows that polarization and incidence angle play a significant role in the potential of the GMRF model for the extraction of urban areas from SAR images. Intersensors comparison evidences the better performances of X-band images, acquired at 1-m spatial resolution, when resampled to resolutions of 5 and 10 m.
La performance de différents types d'images SAR en terme de longueur d'onde, de polarisation, d'angle d'incidence, et de résolution spatiale pour l'extraction des zones urbaines a été analysée. La méthode utilisée est basée sur les paramètres de texture et en utilisant le modèle GMRF (Gaussian Markov Random Field). La comparaison inter-capteur met en évidence les meilleures performances des images en bande X, acquises à 1 m de résolution spatiale et ré-échantillonées à des résolutions de 5 et 10 m.