On the physical characterization of SAR Permanent Scatterers in urban areas

Abstract:
The Permanent Scatterers (PS) technique developed in late nineties by the Politecnico di Milano is a remote sensing tool capable of detecting and monitoring terrain deformation phenomena. Sub-centimetre accuracy is achieved on a sparse grid of radar targets, the so-called Permanent Scatterers. Even if the PS technique is used successfully since 1999, the physical nature of the objects exhibiting PS behaviour is still subject of investigation and research. Indeed, a good knowledge of the PS nature is an essential step to improve the interpretation of the radar measurements and to get a more precise topographic reconstruction. In this work we present the last results of this research program obtained by using more than 200 ERS (3 different acquisition geometries) and Envisat repeated acquisitions on the area of Milano (Italy). The characterization of the physical parameters of the PS would allow us to foresee their electromagnetic behaviour under different acquisition geometries, frequencies and polarizations, and we can develop feasibility studies on the integration of interferometric SAR multiple sensors (e.g. ERS and Envisat coherent exploitation.