RFID detection system
US6577238B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 1, 2001 |
| Grant date | Jun 10, 2003 |
| Priority date | — |
| Expiry date | Mar 1, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K7/10039
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A system 100 is disclosed for monitoring the position of one or more RFID tags 201. The system has a detector 301 incorporating circuitry 304 for detecting changes in the range of an RFID tag 201 from the detector and for triggering an alarm 401 if a detected change in range of an RFID tag 201 exceeds a predetermined threshold or if the RFID radio tag cannot be detected by the detector 301. Range may be detected, for example, by measuring the time of a returned radio signal from a tag 201, by measuring the strength of a returned radio signal from a tag, or by detecting changes in a periodic interval at which energy is transmitted by a tag.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.