RFID transponder having active backscatter amplifier for re-transmitting a received signal
US6838989B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 1999 |
| Grant date | Jan 4, 2005 |
| Priority date | — |
| Expiry date | Dec 22, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K19/0723
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An RFID transponder is provided with an active backscatter amplifier that amplifies and re-transmits a received signal. The RFID transponder comprises an antenna and a circulator having a first port connected to the antenna. A modulator is connected to a second port of the circulator. An amplifier is connected to a third port of the circulator, with the amplifier connected to the modulator. An RF signal impinging upon the antenna passes through the circulator, the amplifier, and the modulator, and returns to the antenna through the circulator. The modulator further comprises an input coupled to the second port of the circulator and an output coupled to an input of the amplifier. The amplifier has an output coupled to the third port of the circulator. The modulator is adapted to modulate the RF signal using on-off keying.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.