Space-borne SAR acquisitions typically cover large areas that may span several hundreds of square kilometers.
However, most civil engineering projects or deformation processes have a local character and both quality as well as the detail of an InSAR analysis can be greatly improved if only a small area (typically 5-10 square kilometers is processed with optimized parameters that suite a specific problem).
In this case, measurements can achieve millimeter accuracy on a dense network of points and non-linear displacement trends can be detected together with the spatial pattern of deformation (displacement maps).
Fragile Srl supplies to the costumers tailor-made site-specific InSAR analysis.
A site-specific InSAR analyses can be composed of two subsequent steps: historical reconstruction of the deformation pattern in the spatial and temporal domain followed by near real-time monitoring of surface displacements.
The historical InSAR analysis represents the base for the subsequent near real-time monitoring.
The historical InSAR analysis helps, for instance, to understand geological processes that act on a given site before or after construction works or a natural deformation event. This information can then be used to improve the design of a ground-based monitoring system for alert and alarm purposes, but it can also be a useful tool during the design/operational phase of an engineering project or to support legal actions.
Once the historical displacement trend is known, it is possible to set the most adequate frequency of InSAR dataset update.
Site-specific InSAR analyses provide by Fragile Srl are particularly suited to analyze the spatial and temporal development of single landslides, natural or man-induced local subsidence phenomena but also settlements over underground excavations and slope deformation in mining areas.
In most cases, site-specific InSAR analyses are realized by the combination of traditional InSAR approach (RAINS, Rapid Areal Insar Survey) and a multi-temporal InSAR technique (MT-SBA). This combination allows to obtain both spatially continuous deformation maps in rural areas, and displacements time-series for pixels that are located on man-made structures and infrastructures.
A bit more on technical aspects check >> Our processing strategies