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:
Apr. 25, 2006
Filed:
Apr. 29, 2004
Todd B. Franklin, Tallahassee, FL (US);
Paul Kelley, Boca Raton, FL (US);
Todd B. Franklin, Tallahassee, FL (US);
Paul Kelley, Boca Raton, FL (US);
Comm-Engines, Tallahassee, FL (US);
Abstract
An anti-theft surveillance system capable of detecting the presence of tags affixed to merchandise. The tags contain a diode attached to two dipole elements. When the tag receives alow frequency signal and a high frequency signal, it will emit two side bands. The system includes alow frequency transmitter, a high frequency transmitter, and a receiver. The two transmitters place alow frequency signal and a high frequency signal in proximity to the guarded area (typically a store doorway). When a tag is near the doorway, the receiver will receive the upper side band and lower side band. The receiver reduces the frequency of the upper and lower side band signals to form an intermediate frequency upper side band and an intermediate frequency lower side band. These two intermediate frequency signals are then fed into two separate detector circuits. One circuit detects the presence of the intermediate frequency upper side band and the other circuit detects the presence of the intermediate frequency lower side band. Only if both side bands are detected is an alarm created.