RFID tag containing two tuned circuits
US7821401B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 5, 2006 |
| Grant date | Oct 26, 2010 |
| Priority date | — |
| Expiry date | Jan 15, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K19/07796
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An RFID tag is disclosed adapted to be read by an interrogator including a reader antenna having a carrier frequency. The tag includes a first circuit including a first inductor and a first capacitor, wherein the first circuit is tuned to a frequency above the carrier frequency to compensate for detuning in the presence of a plurality of tags. The RFID tag includes a second circuit including a second inductor and a second capacitor wherein the first and second inductors are arranged to be coupled electromagnetically with a coupling factor less than unity and the second circuit is tuned to increase coupling between the first circuit and the reader antenna. A method of reading an RFID tag in the presence of a plurality of tags is also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.