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:
May. 04, 1999
Filed:
Jun. 18, 1997
Applicant:
Inventor:
Jon Neal Weaver, Gainesville, FL (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G08B / ;
U.S. Cl.
CPC ...
3405722 ; 340551 ;
Abstract
The present invention relates to a method and apparatus for detecting the presence of a soft magnetic marker in an interrogation zone. This invention utilizes a modulated transmitter carrier signal generated in an interrogation zone. Modulated harmonics of the transmitter carrier signal are detected when a marker is present in the interrogation zone. The modulation detected can be at the same frequency as the modulation of the transmitter signal or a harmonic of the modulation of the transmitter signal. Detection of the modulation allows higher signal to noise ratios and therefore reduces false detections.