Appendix B: Gpr Signal Processing Artifacts; Wow - Sensors & Software pulseEKKO Product Manual

Appendix B

Appendix B: GPR Signal Processing Artifacts

Wow

All GPR data contains a low frequency component; the magnitude of the low frequency
component and how it manifests itself in the data depends on the ground conditions around the
antennas and the distance between the antennas. In general, the low frequency component of
the radar signal does not propagate but diffuses into the ground. In other words, the lower end
of the spectrum sees an inductive (eddy current) type response as opposed to a propagating
(displacement current) type response.
The result is that the large transmit pulse emitted by the radar can be followed by a slowly
decaying transient.
The following diagram shows the effect of inductive Wow on GPR data:
The following image displays a single data trace with the low frequency WOW component
present:
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