Enhanced PSP SAR interferometry for analysis of weak scatterers and high definition monitoring of deformations over structures and natural terrains

Synthetic aperture radar (SAR) interferometry is an effective technology for detection and monitoring of slow terrain movements with millimetric precision. This information is extracted by means of complex techniques from the phase of the signal. Building on the ideas of the persistent scatterer pair (PSP) method, we present an enhanced method aimed at fully extracting the coherent information even from low intensity SAR signals. The proposed method is very effective at extracting the available information from each single pixel of the SAR image where you could expect a coherent signal, even when there are not strongly scattering structures and the sensed signal is weak, as in the case of rather smooth surfaces or natural terrains. Several examples obtained from the processing COSMO-SkyMed data show that unprecedentedly dense ground deformation measurements can be obtained with the enhanced PSP method, not only corresponding to structures but also in natural terrains.