Skip to Content
Find More Like This
Return to Search

Multi-level RF identification system

United States Patent

July 20, 2004
View the Complete Patent at the US Patent & Trademark Office
Pacific Northwest National Laboratory - Visit the Technology Commercialization Program Website
A radio frequency identification system having a radio frequency transceiver for generating a continuous wave RF interrogation signal that impinges upon an RF identification tag. An oscillation circuit in the RF identification tag modulates the interrogation signal with a subcarrier of a predetermined frequency and modulates the frequency-modulated signal back to the transmitting interrogator. The interrogator recovers and analyzes the subcarrier signal and determines its frequency. The interrogator generates an output indicative of the frequency of the subcarrier frequency, thereby identifying the responding RFID tag as one of a "class" of RFID tags configured to respond with a subcarrier signal of a predetermined frequency.
Steele; Kerry D. (Kennewick, WA), Anderson; Gordon A. (Benton City, WA), Gilbert; Ronald W. (Benton City, WA)
Battelle Memorial Institute Kl-53 (Richland, WA)
09/ 802,408
March 9, 2001
This invention was made with Government support under Contract DE-AC0676RLO1830 awarded by the U.S. Department of Energy. The Government has certain rights in the invention.