Wireless power transfer using a microwave signal

• US 9,711,973 B2
• Filed: 04/24/2015
• Issued: 07/18/2017
• Est. Priority Date: 04/24/2015
• Status: Active Grant

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola Solutions, Inc.
• Inventors: Herrmann, John, Wallis, David
• Primary Examiner(s): Fureman, Jared
• Assistant Examiner(s): Yeshaw, Esayas
• Application Number:
  US14/696,082
• Publication Number:
  US 20160315480A1
• Time in Patent Office: 816 Days
• CPC Class Codes: H01F 2038/143 for signals
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H02J 50/20 using microwaves or radio frequency waves

Abstract

A wireless power source including a microwave receiver, a matching network, and a transducer. The microwave receiver receives a microwave signal having a carrier frequency. The matching network receives a signal having the carrier frequency and a switched frequency and removes the carrier frequency such that the matching network outputs a switched signal at the switched frequency. The transducer is configured to receive the switched signal and output a DC voltage.

Claims

1. A wireless power source, the wireless power source comprising:

a microwave receiver to receive a microwave signal having a carrier frequency;

a matching network to receive a signal having the carrier frequency and a switched frequency and to remove the carrier frequency such that the matching network outputs a switched electronic signal at the switched frequency; and

a transducer, having a first coil and a second coil, to receive the switched electronic signal and output a DC voltage.

2. The wireless power source of claim 1, further comprising a switcher to receive the microwave signal from the microwave receiver, adds the switched frequency to the microwave signal, and outputs a combined carrier/switched signal.

3. The wireless power source of claim 2, wherein the switcher adds a second switched frequency to the microwave signal and outputs a second combined carrier/switched signal.

4. The wireless power source of claim 3, further comprising a second matching network which receives the second combined carrier/switched signal from the switcher, the second combined carrier/switched signal having the carrier frequency and the second switched frequency and removes the carrier frequency such that the second matching network outputs a second signal at the second switched frequency;

and

a second transducer configured to receive the second signal and output a second DC voltage.

5. The wireless power source of claim 1, wherein the microwave signal includes the switched frequency.

6. The wireless power source of claim 1, further comprising a second matching network to receive a second combined carrier/switched signal having the carrier frequency and a second switched frequency and to remove the carrier frequency such that the matching network outputs a second signal at the second switched frequency;

and

a second transducer configured to receive the second signal and output a second DC voltage.

7. A method of wireless power transfer, the method comprising:

generating a microwave signal at a carrier frequency;

switching the microwave signal at a switched frequency;

removing, by a receiver, the carrier frequency from the switched microwave signal to produce a switched electronic signal;

applying the switched electronic signal to a transducer having a first coil and a second coil; and

generating, by the transducer, a direct current voltage.

8. The method of claim 7, wherein the microwave signal is switched in the receiver.

9. The method of claim 7, further comprising transmitting the switched microwave signal wirelessly to the receiver.

10. The method of claim 7, further comprising

switching the microwave signal at a second switched frequency;

removing, by the receiver, the carrier frequency from the switched microwave signal to produce a second signal;

applying the second signal to a second transducer; and

generating, by the second transducer, a second direct current voltage.

11. The method of claim 10, wherein the receiver adds the second switched frequency to the microwave signal.

12. The method of claim 10, wherein the second transducer includes a first coil and a second coil.

13. The method of claim 10, wherein the second transducer is an acoustic transducer.