Wireless power transfer
A method of generating a DC power from incident RF waves, includes, in part, measuring the amount of power being received by a device generating the DC power, and controlling the phases of the RF waves being transmitted by a multitude of RF transmitters in accordance with the measured power. A programmable test load is optionally used at the device to measure the received power. The device optionally includes, an antenna, an RF-to-DC converter to generate the DC power, an impedance matching/transformation circuit, and an RF load/matching circuit.
1. A recovery unit adapted to receive a radio frequency (RF) signal and generate a DC power in response, the recovery unit comprising:
at least one antenna for receiving the RF signal;
an RF-to-DC converter generating the DC power from the RF signal;
a detector detecting a signal in response to a presence of a living organism positioned in a path of the received RF signal; and
a wireless communication circuit adapted to cause an RF signal generating unit to vary a power of the RF signal in accordance with the detected signal.
2. The recovery unit of claim 1 wherein said detector comprises an infrared sensor comprising at least one pixel.
3. The recovery unit of claim 1 wherein said detector detects a change in a frequency of a portion of the RF signal.
4. The recovery unit of claim 1 wherein said detector further detects the living organism when the living organism partially blocks the path between the RF signal generating unit and the recovery unit.
5. The recovery unit of claim 1 further comprising: an impedance matching circuit disposed between the at least one antenna and the RF-to-DC converter.
6. The recovery unit of claim 5 further comprising:
an RF circuit coupled to the RF-to-DC converter and adapted to block the RF signal from reaching an output terminal of the RF-to-DC converter.
7. The recovery unit of claim 5 further comprising:
an amplitude detector.
8. The recovery unit of claim 7 wherein said amplitude detector is coupled to an input terminal of the RF-to-DC converter.
9. The recovery unit of claim 7 wherein said amplitude detector is coupled to an output terminal of the RF-to-DC converter.
10. The recovery unit of claim 9 further comprising:
an analog-to-digital converter adapted to convert an output of the amplitude detector to a digital signal.