Self tuning RFID
US8836512B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 28, 2008 |
| Grant date | Sep 16, 2014 |
| Priority date | — |
| Expiry date | Dec 22, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K19/0713
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The antenna of an RFID tag is automatically tuned by controlling both the real and imaginary components impedance “seen” by the antenna. The real component (resistive) is controlled by controlling a tap of a charge pump circuit of the tag. The imaginary (reactive) component is controlled by connecting one or more reactive elements of an antenna tuning circuit to the antenna. The real component is controlled by a first digital control loop that automatically activates successive taps on a charge pump of the RFID tag which effectively controls the resistance seen by the antenna. A second digital control loop controls the connection of the various reactive components.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.