Radiative wireless power transmission

• US 10,263,465 B2
• Filed: 12/12/2016
• Issued: 04/16/2019
• Est. Priority Date: 12/17/2015
• Status: Active Grant

• Current Assignee: WiTricity Corporation
• Original Assignee: WiTricity Corporation
• Inventors: Kurs, Andre B., Soljacic, Marin, Roy, Arunanshu Mohan, Patron, Damiano, Ye, Erika
• Primary Examiner(s): Fureman, Jared
• Assistant Examiner(s): Dominique, Emmanuel
• Application Number:
  US15/375,880
• Publication Number:
  US 20170179764A1
• Time in Patent Office: 855 Days
• CPC Class Codes: H01P 3/16 Dielectric waveguides, i.e. without a longitudinal conductor
• CPC Class Codes: H01P 5/087 Transitions to a dielectric waveguide
• CPC Class Codes: H01P 5/16 Conjugate devices, i.e. devices having at least one port decoupled from one other port
• CPC Class Codes: H01Q 21/0043 Slotted waveguides combination with horns H01Q13/0233
• CPC Class Codes: H01Q 21/005 Slotted waveguides arrays
• CPC Class Codes: H01Q 3/22 varying the orientation in accordance with variation of frequency of radiated wave
• CPC Class Codes: H02J 50/23 characterised by the type of transmitting antennas, e.g. directional array antennas or Yagi antennas
• CPC Class Codes: H03H 7/38 Impedance-matching networks

Abstract

A wireless power transmission system (100) includes a conductive waveguide (110) at least partially filled with a dielectric material (115), the waveguide extending along a first direction (e.g., z-axis) from a first end (111a) to an opposing end (111b) thereof, the waveguide having a bottom face (112), a top face (114) and a pair of side faces (116a, 116b) that together form a substantially rectangular cross-section of the waveguide, the top face having a plurality of slots (118) oriented substantially orthogonal to the first direction and distributed between the first end and the opposing end, the slots separated from each other by a first distance (l₁) measured along the first direction. In one illustrative embodiment, the waveguide includes a plurality of barriers (120) interleaved with the plurality of slots, the barriers separated from each other by the first distance, each of the barriers extending between the top and bottom faces and having a barrier cross-section with an area smaller than an area of the waveguide cross-section and an input port (130) coupled with the first end of the waveguide, the input port configured to receive an input waveform (101) to be guided by the waveguide.

Claims

1. A wireless power transmission system comprising:

a conductive waveguide at least partially filled with a dielectric material, the waveguide extending along a first direction from a first end to a second, opposing end thereof, the waveguide having a bottom face, a top face and a pair of side faces that together form a substantially rectangular cross-section of the waveguide, the top face having a plurality of slots oriented substantially orthogonal to the first direction and distributed between the first and second ends, with adjacent slots spaced from each other by a first distance measured along the first direction, the waveguide comprising

a plurality of barriers interleaved with the plurality of slots, the barriers separated from each other by the first distance, each of the barriers extending between the top and bottom faces and having a barrier cross-section with an area smaller than an area of the waveguide cross-section; and

an input port coupled to the first end of the waveguide, the input port configured to receive an input waveform to be guided by the waveguide;

wherein each of the side faces comprises a plurality of conductive vias distributed from the first end to the opposing end, and

each of the barriers comprises two conductive vias spaced apart from each other by a second distance measured orthogonal to the first direction, and from an adjacent slot by a third distance measured along the first direction.

2. The wireless power transmission system of claim 1 wherein

the waveguide cross-section is configured to cause the waveguide to guide, from the first end to the opposing end, the input waveform having a frequency in a target frequency range, and

a combination of the first distance, the second distance and the third distance is configured to cause an output wave having the frequency of the input waveform to exit the waveguide through the plurality of slots along a propagation direction that forms a first angle, relative the first direction, associated with the frequency of the input waveform.

3. The wireless power transmission system of claim 2 comprising:

a plurality of waveguides arranged along the first direction, and separated from each other by a predetermined separation measured orthogonal to the first direction; and

a plurality of input ports coupled with the first end of each of the respective waveguides, each of the input ports configured to receive a respective input waveform to be guided by the associated waveguide.

4. The wireless power transmission system of claim 3 wherein

the input waveforms applied at the input ports have the same frequency and corresponding phases, and

a combination of the phases and the predetermined separation between the waveguides is configured to cause the output wave to exit the waveguides through the slots along a propagation direction that has a first component that forms the first angle with the first direction and a second component that forms a second angle relative to a direction orthogonal to the first direction.

5. The wireless power transmission system of claim 1 wherein the conductive waveguide comprises a metal or a conductive polymer.

6. The wireless power transmission system of claim 1 wherein the dielectric material comprises low electrical loss material.

7. The wireless power transmission system of claim 1 wherein the dielectric material comprises ceramic, glass, polytetrafluoroethylene, polycarbonate or acrylic.

8. The wireless power transmission system of claim 1 wherein the input port comprises a coaxial cable connector.

9. The wireless power transmission system of claim 8 wherein the input port further comprises impedance matching circuitry.

10. The wireless power transmission system of claim 1 comprising:

a waveform source coupled with the input port to provide the input waveform to the input port.

11. A wireless power transmission system comprising:

a conductive waveguide at least partially filled with a dielectric material, the waveguide extending along a first direction from a first end to a second, opposing end thereof, the waveguide having a bottom face, a top face and a pair of side faces that together form a substantially rectangular cross-section of the waveguide, the top face having a plurality of slots oriented substantially orthogonal to the first direction and distributed between the first and second ends, with adjacent slots spaced from each other by a first distance measured along the first direction, the waveguide comprising

a plurality of barriers interleaved with the plurality of slots, the barriers separated from each other by the first distance, each of the barriers extending between the top and bottom faces and having a barrier cross-section with an area smaller than an area of the waveguide cross-section; and

an input port coupled to the first end of the waveguide, the input port configured to receive an input waveform to be guided by the waveguide;

wherein each of the side faces comprises a conductive plate extending from the first end to the opposing end, and

each of the barriers comprises two conductive plates arranged orthogonally to the respective side faces and separated from each other by a second distance and from an adjacent slot by a third distance.

12. The wireless power transmission system of claim 11 wherein

the waveguide cross-section is configured to cause the waveguide to guide, from the first end to the opposing end, the input waveform having a frequency in a target frequency range, and

a combination of the first distance, the second distance and the third distance is configured to cause an output wave having the frequency of the input waveform to exit the waveguide through the plurality of slots along a propagation direction that forms a first angle, relative the first direction, associated with the frequency of the input waveform.

13. The wireless power transmission system of claim 11 wherein the conductive waveguide comprises a metal or a conductive polymer.

14. The wireless power transmission system of claim 11 wherein the dielectric material comprises low electrical loss material.

15. The wireless power transmission system of claim 11 wherein the dielectric material comprises ceramic, glass, polytetrafluoroethylene, polycarbonate or acrylic.

16. The wireless power transmission system of claim 11 wherein the input port comprises a coaxial cable connector.

17. The wireless power transmission system of claim 16 wherein the input port further comprises impedance matching circuitry.

18. The wireless power transmission system of claim 11 comprising:

a waveform source coupled with the input port to provide the input waveform to the input port.

19. A method for wireless power transmission, the method comprising:

receiving, at an antenna, a first input waveform having a first frequency, wherein the antenna comprises a first 1D-array of resonance cavities that are coupled with their adjacent cavities and through partially transmissive barriers, and have respective slots arranged orthogonally to a first direction that is parallel to the first 1-D array of resonance cavities, wherein the first input waveform is received at a first input port coupled to a first resonance cavity of the first 1D-array of resonance cavities;

guiding the first input waveform through the first 1D-array of coupled resonance cavities;

radiating a first output wave having the first frequency of the first input waveform through the slots along a propagation direction that forms a first angle, relative the first direction, the first angle being associated with the first frequency of the first input waveform;

receiving, at the first input port a second input waveform having a second frequency different from the first frequency;

guiding the second input waveform through the first 1D-array of coupled resonance cavities; and

radiating a second output wave having the second frequency of the second input waveform through the slots along another propagation direction that forms a second angle, relative the first direction, the second angle being different from the first angle and associated with the second frequency of the second input waveform.

20. A method for wireless power transmission, the method comprising:

receiving, at an antenna, a first input waveform having a first frequency, wherein the antenna comprises a first 1D-array of resonance cavities that are coupled with their adjacent cavities and through partially transmissive barriers, and have respective slots arranged orthogonally to a first direction that is parallel to the first 1-D array of resonance cavities, wherein the first input waveform is received at a first input port coupled to a first resonance cavity of the first 1D-array of resonance cavities;

guiding the first input waveform through the first 1D-array of coupled resonance cavities;

radiating a first output wave having the first frequency of the first input waveform through the slots along a propagation direction that forms a first angle, relative the first direction, the first angle being associated with the first frequency of the first input waveform;

receiving, at a plurality of input ports that includes the first input port, first input waveforms having corresponding phases, wherein the input ports are coupled with respective 1D-arrays of coupled resonance cavities that include the first 1D-array of coupled resonance cavities, the 1D-arrays of coupled resonance cavities being parallel to each other and separated from each other by a predetermined separation;

guiding the first input waveforms through the respective 1D-arrays of coupled resonance cavities; and

radiating the first output wave through the slots along another propagation direction that has a first component that forms the first angle relative the first direction, and a second component that forms another angle relative to a direction orthogonal to the first direction.