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:
Mar. 19, 1991
Filed:
Jul. 02, 1990
Earl J Peterman, Philo, CA (US);
David L Peterman, Redwood Valley, CA (US);
Heath Consultants, Inc., Houston, TX (US);
Abstract
An apparatus and method for determining the location of a concealed conductive object. The method includes the steps of determining the lateral position of the object by using an antenna array to detect a signal propagating on the object. The antenna array is comprised of at least one center antenna positioned perpendicular to a surface concealing the object and at least two antennas symmetrically positioned about the center antenna at angles not equal to ninety degrees. The depth of the concealed object is determined by using a bottom sensor to detect the signal propagating on the object as a first signal. A vertically displaced top sensor then detects the signal as a second signal which is amplified by a variable gain amplifier until it equals the first signal. The depth of the object is calculated from the gain increase required to achieve equality between the first and second signals. The variable gain amplifier comprises a plurality of iteratively connected amplifiers whose gains are set by digital commands from an up/down counter. The gain increase is determined by a direct current, digital-to-analog converter amplifier which receives the same digital commands as the variable gain amplifier. The lateral direction to the object is determined by comparing the phase of the signal generated by the antenna array to a reference phase.