RFID transponder with PLL
US8629759B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 28, 2008 |
| Grant date | Jan 14, 2014 |
| Priority date | — |
| Expiry date | Jul 29, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K19/0723
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An RFID transponder comprises an antenna for receiving data in a downlink mode and transmitting data in an uplink mode, with a modulation stage for modulating uplink data and a demodulation stage for demodulating downlink data. A class C amplifier is provided, which has a resonant circuit, a plucking device coupled to the resonant circuit, and a controllable pulse width generator coupled to the plucking device. The controllable pulse width generator is adapted to periodically switch the plucking device on and off so as to maintain an oscillation of the resonant circuit. The transponder further comprises a phase locked loop configured to be locked to an oscillating signal received through the antenna and to be switched into a free running mode without being locked to the oscillating signal received through the antenna, thereby being adapted to output an independent internal clock signal for the RFID transponder.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.