On the Selection Criteria for Pixel Candidates in Psi: Potentials of Polarimetry

In this paper we demonstrate some benefits of using polarimetric data in persistent scatterers interferometry (PSI). A polarimetric optimization approach is applied to TerraSAR-X dual-pol data, leading to a significant increase in the number of persistent scatterer candidates (PSCs) selected by the most commonly used criteria of quality, namely the amplitude dispersion index and the average interferometric coherence. The increase of PSCs translates into denser and more accurate deformation estimation results. In addition, a new selection criterion based on polarimetric stationarity is proposed as a way to make a more complete use of the polarimetric information available, since traditional selection criteria are conceived for single-pol data. Preliminary results are shown and discussed.