System and method for communicating with dormant radio frequency identification tags
US6693511B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 24, 1999 |
| Grant date | Feb 17, 2004 |
| Priority date | — |
| Expiry date | Sep 24, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S13/751
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The position of a radio frequency identification (RFID) transponder may be determined with respect to a plurality of stationary sensors located in an array within certain physical areas. Each sensor comprises a plurality of antenna coils arranged in unique physical orientations and capable of transmitting radio frequency signals of differing phase. The RFID transponder includes an antenna which receives the plurality of signals generated by the antenna coils, and compares the phase of at least two of the signals to determine the relative position of the transponder. The location of the transponder with respect to two or more sensor(s) may also be determined through measurement of the intensity of the signals received by the antenna coil of the transponder. The system and method may also transmit data between a sensor and a dormant (motionless) RFID transponder using a hand-held high intensity RF probe.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.