07248165 is referenced by 47 patents and cites 16 patents.

The present invention provides a multi-band, multi-mode RFID tag that uses a single antenna structure and integrated circuit to provide asset location information at any stage of a supply chain. The unified tag design operates at multiple frequencies (or bands) using the antenna structure, for example, 125 kHz, 13.56 MHz, 915 MHz, and 2.45 GHz, and preferably operates electrostatically (at lower frequencies) and electromagnetically (ay higher frequencies). An on-chip frequency monitor in the integrated circuit automatically determines which frequency is present and derives a local clock for the tag's integrated circuit, which can vary in accordance with the frequency or which can be constant. Alternatively, a phase locked loop circuit can be used to derive a local clock signal modulated into the interrogation signal. On-chip matching and power extraction circuits derive power for the tag from the interrogation signal, which is preferably passive. Additionally, a receiver can receive data from the interrogation signal.

Title
Method and apparatus for multiple frequency RFID tag architecture
Application Number
10/937208
Publication Number
7248165 (B2)
Application Date
September 9, 2004
Publication Date
July 24, 2007
Inventor
Richard S Rachwalski
Lemont
IL, US
Stephen L Kuffner
Algonquin
IL, US
David P Gurney
Carpentersville
IL, US
Timothy J Collins
Homer Glen
IL, US
Assignee
Motorola
IL, US
IPC
G08B 13/14
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