The need of reliable monitoring of old embankment dams is rapidly increasing since a large number of these structures
are still equipped with old monitoring devices, usually installed some decades ago, which are generally capable to
provide only localized information on specific areas of the embankment. This work discusses the use of Ground-Based
Synthetic Aperture Radar (GBSAR) interferometry technique to observe and control the structural behavior of earthfill
or rockfill embankments for dam impoundments. This non-invasive technique provides displacements patterns measured
with sub-millimeter precision. Monitoring strategies of earthfill dam embankment in Southern Italy are presented.
The problems of simulation of bistatic SAR raw data and focusing are studied. A discrete target simulator is described.
The simulator introduces the scene topography and compute the integration time of general bistatic configurations
providing a means to derived maps of the range and azimuth spatial resolutions. The problem of focusing of bistatic SAR
data acquired in a translational-invariant bistatic configuration is studied by deriving the bistatic Point Target Reference
spectrum and presenting an analytical solution for its stationary points.
A Ground-Based Synthetic Aperture Radar (GB-SAR) is nowadays employed in several applications. The processing of
ground-based, space and airborne SAR data relies on the same physical principles. Nevertheless specific algorithms for
the focusing of data acquired by GB-SAR system have been proposed in literature.
In this work the impact of the main focusing methods on the interferometric phase dispersion and on the coherence has
been studied by employing a real dataset obtained by carrying out an experiment. Several acquisitions of a scene with a
corner reflector mounted on a micrometric screw have been made; before some acquisitions the micrometric screw has
been displaced of few millimetres in the Line-of-Sight direction. The images have been first focused by using two
different algorithms and correspondently, two different sets of interferograms have been generated. The mean and
standard deviation of the phase values in correspondence of the corner reflector have been compared to those obtained by
knowing the real displacement of the micrometric screw. The mean phase and its dispersion and the coherence values for
each focusing algorithm have been quantified and both the precision and the accuracy of the interferometic phase
measurements obtained by using the two different focusing methods have been assessed.