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:
Aug. 31, 2004
Filed:
Jul. 08, 1999
Kursat Eroglu, Mukilteo, WA (US);
Patrick L. Helton, Marysville, WA (US);
Christopher A. Wiklof, Everett, WA (US);
Intermec IP Corp., Beverly Hills, CA (US);
Abstract
An RFID tag verifier includes an RF interrogator that transmits a first and second interrogation signal each having a first operational characteristic that differs from the other by a known amount. The RF interrogator receives a first and second return signal corresponding to the respective interrogation signals. A processor determines a response of the RFID tag as defined by a second operational characteristic of the first and second return signals. The verifier can determine the signal strength of the return signal for varying strengths of the interrogation signal. Typically, a flat response is desired Additionally, or alternatively, the verifier can determine the response in terms of signal strength of the response signals for interrogation signals having different frequencies. In some applications frequency selectivity may be desirable. Additionally, or alternatively, the verifier can determine the response in terms of frequency for interrogation signals having varying strengths. A machine-readable symbol verifier can be coupled to, or formed as part of, the RFID verifier. A printer can be coupled to, or formed as part of, the RFID tag verifier.