Synthetic Aperture Radar: a New Application for Wave Equation Techniques
, by Fabio Rocca
The techniques of downward continuation and imaging invented for seismic
waves can be applied to other types of waves.
In this paper, we see how this application can be made in the case of
electromagnetic surveys conducted with Synthetic Aperture Radar (SAR).
The algorithms used closely follow those used for seismic waves.
Differences are induced by alternate wavelengths, wave velocities,
distances between sources and reflectors etc.
In the case that we analyze in detail, a survey
carried out using a satellite, difficulties arise from the fact that
the orbit of the satellite cannot be approximated with a simple straight line
if the spatial resolution of the survey is high.
We determine appropriate techniques for the correction of the
distortion induced by the latter and we delimit
the resolution of the observed data, as seen from a satellite.
Finally we show examples of the application of the technique of seismic
migration to satellite data that
were irradiated to earth during the short but
productive life of SEASAT.