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. 14, 1989
Filed:
Aug. 31, 1987
John F Feltz, Fairborn, OH (US);
John W Taylor, Springboro, OH (US);
Richard S Vuketich, Dayton, OH (US);
Monarch Marking Systems, Inc., Dayton, OH (US);
Abstract
An electronic article surveillance system employs a resonant tag attached to an article being protected. An interrogation transmitter whose transmission frequency is periodically swept through the resonant frequency of the tag is positioned near an exit of the protected area. The resonant tag is periodically energized by the transmitter as the transmitter frequency passes through the resonant frequency of the tag to cause the tag to emit a periodic tag signal at the sweep rate of the transmitter. The tag signal is received by a receiver that generates an alarm upon the detection of a tag signal. The receiver employs synchronous integration in the form of a dual channel synchronous video integrator to independently process positive and negative pulses of the tag signal in order to differentiate the tag signal from extraneous signals and noise.