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:
Jan. 10, 1995
Filed:
Oct. 26, 1992
Sanjar Ghaem, Palatine, IL (US);
Rudyard L Istvan, Winnetka, IL (US);
George L Lauro, Lake Zurich, IL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
RF tagging system (10) has a plurality of resonant circuits (13) on a tag (12). When the tag (12) enters a detection zone (14), the system determines the resonant frequency of each of the resonant circuits (13) and produces a corresponding code. Preferably, resonant frequency detection is implemented by simultaneously radiating signals at each possible resonant frequencies for the tag circuits (13). The system is useful for coding any articles such as baggage or production inventory. Preferably, the radiated signals are phase shifted during the detection process, and signals received by receiver antennas, besides transmitter signals, may be monitored to improve the reliability of detecting the resonant circuits (13). Also, a preferred step adjustment configuration for capacitive metalizations (106, 110) of the resonant circuits is described. For radiating signals into the detection zone (14), focused beam antennas (201) may be used such that each resonant circuit location on the tag can be separately monitored. Also, an apparatus (300) for producing customized resonant circuit tags in accordance with a specified input code is described.