The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 06, 1992
Filed:
Mar. 26, 1990
Henning F Harmuth, Sydney, AU;
Geophysical Survey Systems, Inc., North Salem, NH (US);
Abstract
An electromagnetic signal having originally the time variation of a rectangular pulse is transmitted into a medium with conductivity .sigma.. It is distorted by the medium to a signal f(.sigma.,d,t) if it traveled the distance d from a transmitter to a scattering or reflecting object and the same distance d back to the transmitter. The time variation f(.sigma.,d,t) of the distorted signal can be calculated for any conductivity .sigma. and distance d. Using the conductivity .sigma. known from previous measurements, the returned, distorted signal f(t) is compared with computed distorted signals f(.sigma.,d,t) for various distances d. The computed signal f(.sigma.,d,t) that is most similar to the actually received signal f(t) determines the distance d to the scattering or reflecting object. The comparison between the computed, distorted signals and the actually received signal is done by cross-correlations. The peak amplitude or the energy of the received signal becomes unimportant if cross-correlation is used, which means the physical size or radar cross-section of the scattering or reflecting object becomes unimportant.