Time-lapse GPR measurement to study the imaging operator

Time-lapse GPR measurement to study the imaging operator

Zeeman, J.H.
Groenenboom, J.
Van der Kruk, J.

Molengraaff Fonds

2001

This paper aims at improving imaging algorithms for ground penetrating radar data. Recent efforts try to achieve this by incorporating the electromagnetic vector propagation, describing the source and receiver antenna as far field point-source radiation patterns. Here, we show that a theoretically sound imaging operator can be constructed based on the response of an approximate point scatterer, including the effect of source and receiver antenna. With an automated frame we have measured a three-dimensional data set over homogeneous sand. Then we buried a scatterer at a depth of roughly a half a meter and measured the data set again. By subtracting these data sets i n a time lapse manner we can roughly estimate the point scatterer response. We have compared this response with the far field point source/receiver response and show that for the real data the amplitude versus offset to the scatterer falls off much more rapidly than according to theory. The two most likely causes of this fact are the finite aperture of the antennas and the attenuation in the ground. In principle the measured data can be used to construct improved imaging operators.

http://resolver.tudelft.nl/uuid:b99dde20-de57-44b1-b61d-a9495b8408a1

Geoscience and Engineering

Geoscience Reports

report

(c) Jan Harry Zeeman; Jeroen Groenenboom; Jan van der Kruk