An interferometric technique for synthetic aperture ground-penetrating radar

Many synthetic aperture radar (SAR) algorithms for ground-penetrating radar involve making measurements along a single path and using the collected data to form a two-dimensional image of the scattering object. In the calculation of these images, certain assumptions are made about the scattering objects; mainly, that the reflections are occurring directly below the antenna location, which is not always the case. By applying interferometric techniques to SAR-based images, it is possible to construct an image of the scattering object that contains all three dimensions rather than only two, eliminating the need for these assumptions. This paper proposes a method of combining radar interferometry with SAR-based ground-penetrating radar. The methodology used is to expand several two-dimensional images, each calculated from measurements collected along single paths, into a three-dimensional image of the scattering object through the use of radar interferometry. This process involves superimposing two complex two-dimensional images and using the information found in the phase differences of corresponding locations from each image to calculate the location of the object in the dimension not contained within the previous two-dimensional images. This method is tested using both computer-simulated data and also data collected from the measurements of objects buried in sand