Energy harvesting in RFID systems
Methods, systems, and apparatuses for providing power to devices that are part of RFID systems are described. Energy is harvested at portable/mobile devices, stored and conditioned to provide on-going power as needed for various circuits/components. The energy may be generated in a variety of ways, including using a vibratory energy harvesting device, a magnetic energy harvesting device, and an optical energy harvesting devices.
1. A method for providing supplemental power to a Radio Frequency Identification (RFID) interrogator in a headset in an RFID system, comprising:
mounting a microphone boom of the headset to a piezoelectric transducer, wherein a vibration of the boom deflects the piezoelectric transducer to generates a current due to the deflection;
integrating an RFID tag within the microphone boom of the headset, the RFID tag including a charge pump for harvesting energy from an antenna of the RFID tag, the energy obtained from any RFID interrogators in the RFID system;
charging an energy storage device disposed within a body of the headset with the generated energy from the RFID tag and the current from the piezoelectric transducer;
conditioning power from the energy storage device with a buck boost regulator disposed within a body of the headset; and
powering the RFID interrogator of the headset with the conditioned power from the energy stored in the energy storage device.
2. The method of claim 1 , wherein said generating comprises:
inducing a current in an antenna receiving a signal from any RFID interrogator in the RFID system; and
conditioning the current induced in the antenna for storage in the energy storage device.
3. An arrangement for providing supplemental power to a Radio Frequency Identification (RFID) interrogator in a headset in an RFID system, comprising:
a microphone boom of the headset mounted to a piezoelectric transducer, wherein a vibration of the boom deflects the piezoelectric transducer to generates a current due to the deflection;
an RFID tag integrated within the microphone boom of the headset, the RFID tag including an energy harvesting device for harvesting energy from an antenna of the RFID tag, the energy obtained from any RFID interrogators in the RFID system;
an energy storage device disposed within a body of the headset constructed and arranged to store power harvested by the energy harvesting device and from the RFID tag and the current from the piezoelectric transducer; and
a powering conditioning circuit disposed within a body of the headset for conditioning power from the energy storage device and providing conditioned power to the RFID interrogator of the headset.
4. An arrangement according to claim 3 wherein the energy storing device is a capacitor.
5. An arrangement according to claim 3 wherein the energy storing device is a battery.