Frequency analysis of InSAR time series.

The use of Synthetic Aperture Radar (SAR) satellite technology as an indirect geodetic tool for measuring the deformation of the Earth's surface has been increasingly used in recent decades, thanks to its important applications in both scientific fields as a support for understanding deformation processes, also at large scales, and as a monitoring tool for the protection of populations and structural assets. In particular, the analysis of displacement time-series data of a specific area over time allows for the understanding and study of deformation dynamics, enabling the analysis of both their static and cyclic components. The experimental application of frequency analysis to InSAR time series data, applied to a case study of surface deformation covering an area of approximately 12432 km${}^{2}$ between Campania, Basilicata, and Puglia, has allowed the separation of deformation into different components based on their characteristic cyclic period. This has enabled a simpler interpretation of the individual deformation contributions, characterized by different periodicities that are simultaneously active and therefore contribute to the total deformation dynamics of the observed area.