Operation in very close coupling of an electromagnetic transponder system
US6703921B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 5, 2000 |
| Grant date | Mar 9, 2004 |
| Priority date | — |
| Expiry date | Apr 5, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K19/0723
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and a system of data transmission between a terminal for generating an electromagnetic field and a transponder, the terminal and the transponder each including an oscillating circuit forming an antenna, and the transponder including an electronic circuit adapted to absorbing and giving back power provided by the terminal field, the oscillating circuits of the transponder and of the terminal being capable of transmitting radio-electric signals of determined frequency, this method including causing a detuning of at least one of the oscillating circuits with respect to the determined frequency when the transponder and the terminal are very close to each other.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.