System wirelessly transferring power to a target device over a modeled transmission pathway without exceeding a radiation limit for human beings

• US 9,825,358 B2
• Filed: 04/21/2014
• Issued: 11/21/2017
• Est. Priority Date: 12/17/2013
• Status: Active Grant

• Current Assignee: The Invention Science Fund II, L.L.C. (Intellectual Ventures LLC)
• Original Assignee: Elwha LLC (Intellectual Ventures LLC)
• Inventors: Chen, Pai-Yen, Driscoll, Tom, Ebadi, Siamak, Hunt, John Desmond, Landy, Nathan Ingle, Machado, Melroy, Perque, Jr., Milton, Smith, David R., Urzhumov, Yaroslav A.
• Primary Examiner(s): Fureman, Jared
• Assistant Examiner(s): Yeshaw, Esayas
• Application Number:
  US14/257,415
• Publication Number:
  US 20150171514A1
• Time in Patent Office: 1,310 Days
• CPC Class Codes: H01Q 15/002 said selective devices being reconfigurable or tunable, e.g. using switches or diodes
• CPC Class Codes: H01Q 15/148 with means for varying the reflecting properties H01Q15/147 takes precedence
• CPC Class Codes: H01Q 19/067 using a hologram
• CPC Class Codes: H01Q 3/00 Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system means for positioning H01Q1/125
• CPC Class Codes: H01Q 3/247 by switching different parts of a primary active element
• CPC Class Codes: H01Q 3/46 Active lenses or reflecting arrays
• CPC Class Codes: H02J 50/23 characterised by the type of transmitting antennas, e.g. directional array antennas or Yagi antennas
• CPC Class Codes: H02J 50/60 responsive to the presence of foreign objects, e.g. detection of living beings
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices

Abstract

Described embodiments include a system, method, and apparatus. The system includes an antenna comprising a sub-Nyquist holographic aperture configured to define selectable arbitrary complex radiofrequency electromagnetic fields on a surface of the antenna. A mapping engine models an environment within a space radiateable by the antenna. The environment includes a target device and a human being. An optimization circuit selects responsive to the model of the environment a power transmission regime. The power transmission regime includes radiation pattern shaped to wirelessly transfer electromagnetic power from the antenna to the target device without exceeding a radiation exposure limit for humans. A gain definition circuit selects a complex radiofrequency electromagnetic field implementing the selected power transmission regime from the at least two selectable arbitrary complex radiofrequency electromagnetic fields. An antenna controller defines the selected arbitrary complex radiofrequency electromagnetic field in the sub-Nyquist holographic aperture.

Claims

1. A system comprising:

an antenna comprising a sub-Nyquist holographic aperture configured to define at least two selectable, arbitrary complex radiofrequency electromagnetic fields on a surface of the antenna over an operating frequency;

a mapping engine configured to model an environment within a space radiateable by the antenna, the environment including a target device and a human being;

an optimization circuit configured to select responsive to the model of the environment a wireless power transmission regime, the wireless power transmission regime including an electromagnetic radiation pattern shaped to wirelessly transfer radiofrequency electromagnetic power from the antenna to the target device without exceeding a radiofrequency electromagnetic wave radiation exposure limit for human beings;

a gain definition circuit configured to select a complex radiofrequency electromagnetic field implementing the selected wireless power transmission regime from the at least two selectable, arbitrary complex radiofrequency electromagnetic fields; and

an antenna controller configured to define the selected, arbitrary complex radiofrequency electromagnetic field in the sub-Nyquist holographic aperture.

2. The system of claim 1, wherein the sub-Nyquist holographic aperture and the surface are cooperatively structured so that radiofrequency electromagnetic waves incident upon the surface are coherently reconstructed by the selected arbitrary complex radiofrequency electromagnetic field and transmitted to the target device.

3. The system of claim 1, wherein the sub-Nyquist holographic aperture and the surface are structured to cooperatively transmit an electromagnetic waves into free space, the transmitted electromagnetic waves coherently reconstructed by the sub-Nyquist holographic aperture from received incident waves and having a radiation pattern defined by the selected arbitrary complex radiofrequency electromagnetic field.

4. The system of claim 1, further comprising:

a radiofrequency electromagnetic wave generating apparatus configured to generate and deliver radiofrequency electromagnetic waves to the surface of the antenna, the frequency of the radiofrequency electromagnetic waves within at least a portion of the operating frequency of the antenna.

5. The system of claim 1, wherein the sub-Nyquist holographic aperture is configured to define at least two selectable, arbitrary complex radiofrequency electromagnetic fields on a surface with tangential wavenumbers up to the free-space wavenumber (k₀).

6. The system of claim 1, wherein the sub-Nyquist holographic aperture is configured to define at least two selectable, arbitrary complex radiofrequency electromagnetic fields on a surface with tangential wavenumbers up to 2π

over the aperture spacing (k_apt=2π

/a).

7. The system of claim 1, wherein the sub-Nyquist holographic aperture and the surface are structured to cooperatively transmit electromagnetic waves into free space, the transmitted electromagnetic waves coherently reflected by the sub-Nyquist holographic aperture from received incident waves and having a radiation pattern defined by the selected arbitrary complex radiofrequency electromagnetic field.

8. The system of claim 1, wherein the antenna includes a substantially planar arrangement of at least two antenna segments.

9. The system of claim 1, wherein the antenna includes a radiofrequency electromagnetic wave radiating element and an electronically controllable or tunable reflective surface.

10. The system of claim 1, wherein the antenna includes an electronically controllable or tunable lens configured to define the at least two selectable, arbitrary complex radiofrequency electromagnetic fields on a surface of the lens.

11. The system of claim 1, wherein the target device is configured to receive the radiofrequency electromagnetic power wirelessly transmitted by the antenna.

12. The system of claim 1, wherein the human being includes a stationary human being or a human being in motion.

13. The system of claim 1, wherein the mapping engine is configured to three-dimensionally model the environment within the space radiateable by the antenna.

14. The system of claim 1, wherein the mapping engine is configured to periodically update the model of the environment within the space radiateable by the antenna.

15. The system of claim 1, wherein the mapping engine is configured to automatically update the model of the environment within the space radiateable by the antenna.

16. The system of claim 1, wherein the mapping engine is configured to at least partially model the location of the target device in response to a signal transmitted by the target device or in response to a signal reflected by the target device.

17. The system of claim 1, wherein the mapping engine is configured to at least partially model the environment in response to data generated using a channel sounding technique.

18. The system of claim 1, wherein the model of the environment includes a model of a power transmission pathway between the antenna and the target device.

19. The system of claim 1, wherein the mapping engine is configured to at least partially model the environment in response to sensor-acquired data indicative of a characteristic or parameter of the environment or in response to radio-frequency acquired data indicative of a characteristic or parameter of the environment.

20. The system of claim 1, wherein the mapping engine is configured to model a location of the human being in the environment.

21. The system of claim 1, wherein the mapping engine is configured to at least partially model the environment in response to data integrated using a multisensor data fusion technique or process.

22. The system of claim 1, wherein the mapping engine is configured to three-dimensionally model the environment within the space at least partially in response to data received from the target device.

23. The system of claim 1, further comprising:

a path analysis engine configured to test the selected wireless power transmission regime.

24. The system of claim 1, wherein the gain definition circuit is configured to determine a matrix representation of a transfer function responsive to the wireless power transmission regime, and to select a complex radiofrequency electromagnetic field implementing the matrix representation of the transfer function from the at least two selectable arbitrary complex radiofrequency electromagnetic fields.

25. The system of claim 1, wherein the gain definition circuit is configured to describe according to holographic principles an antenna radiation pattern responsive to the model of the environment, and to select a complex radiofrequency electromagnetic field implementing the described antenna radiation pattern from the at least two selectable arbitrary complex radiofrequency electromagnetic fields.

26. The system of claim 1, wherein the gain definition circuit is configured to determine a holographic transmission function calculated to produce to the wireless power transmission regime, and to select a complex radiofrequency electromagnetic field implementing the holographic transmission function from the at least two selectable arbitrary complex radiofrequency electromagnetic fields.

27. The system of claim 1, wherein the gain definition circuit is configured to select complex radiofrequency electromagnetic field maximizing radiofrequency electromagnetic radiation delivered to the target device, the selection constrained by a radiofrequency electromagnetic wave radiation exposure limit defined for human beings.

28. The system of claim 1, wherein the gain definition circuit is configured to select responsive to the wireless power transmission regime a complex radiofrequency electromagnetic field implementing the selected wireless power transmission regime in an antenna having at least two aperture segments, the selected complex radiofrequency electromagnetic field having an amplitude or phase selected to maximize the combined electromagnetic radiation delivered to the target device in view of a constraint limiting the radiofrequency electromagnetic radiation limit for human beings.

29. The system of claim 1, wherein the gain definition circuit is configured to select responsive to the wireless power transmission regime a series of at least two complex radiofrequency electromagnetic fields from the at least two selectable, arbitrary complex radiofrequency electromagnetic fields definable by the antenna, the series of at least two radiation patterns selected to facilitate an iterative convergence on an arbitrary complex radiofrequency electromagnetic field delivering a maximum electromagnetic radiation to the target device and constrained by a radiofrequency electromagnetic wave radiation exposure limit defined for human beings.

30. The system of claim 1, wherein the gain definition circuit includes an adaptive gain definition circuit configured to select a second complex radiofrequency electromagnetic field of the at least two selectable, arbitrary complex radiofrequency electromagnetic fields, the selection of the second complex radiofrequency electromagnetic field responsive to electromagnetic radiation received by the target device and electromagnetic radiation received by a human being with the antenna configured in a first complex radiofrequency electromagnetic field of the at least two selectable, arbitrary complex radiofrequency electromagnetic fields.

31. The system of claim 1, further comprising at least one device configured to detect or measure a characteristic or parameter of the environment.

32. The system of claim 31, further comprising a multisensor data fusion system configured to receive data indicative of a characteristic or parameter of the environment from at least two devices, and to generate an estimate of a characteristic or parameter of the environment.

33. The system of claim 1, further comprising:

a power transfer manager configured to initiate, modify, or terminate a transfer of radiofrequency electromagnetic energy from the antenna to the target device.

34. The system of claim 1, further comprising:

a communications module configured to communicate with the target device.

35. The system of claim 1, further comprising;

an update manager configured to initiate an update of the selected wireless power transmission regime.

36. A method comprising:

modeling an environment within a space radiateable by an antenna, the environment including a target device and a human being;

selecting responsive to the model of the environment a wireless power transmission regime, the wireless power transmission regime including an electromagnetic radiation pattern shaped to wirelessly transfer radiofrequency electromagnetic power from the antenna to the target device without exceeding a radiofrequency electromagnetic wave radiation exposure limit for human beings;

selecting a complex radiofrequency electromagnetic field implementing the selected wireless power transmission regime from at least two selectable, arbitrary complex radiofrequency electromagnetic fields definable on a surface of the antenna over an operating frequency;

receiving radiofrequency electromagnetic waves;

coherently reconstructing the received radiofrequency electromagnetic waves with the selected complex radiofrequency electromagnetic field defined on the surface; and

wirelessly transmitting the coherently reconstructed radiofrequency electromagnetic waves to the target device.

37. The method of claim 36, wherein the at least two selectable, arbitrary complex radiofrequency electromagnetic fields definable on a surface have tangential wavenumbers up to the free-space wavenumber (k₀).

38. The method of claim 36, wherein the at least two selectable, arbitrary complex radiofrequency electromagnetic fields definable on a surface have tangential wavenumbers up to 2π

over the aperture spacing (k_apt=2π

/a).

39. The method of claim 36, further comprising:

defining the selected complex radiofrequency electromagnetic field on the surface.

40. The method of claim 36, wherein the modeling includes iteratively updating the modeling an environment within the space radiateable by the antenna.

41. The method of claim 36, further comprising:

testing the respective at least two power transmission pathways at least partially in response to sensor-acquired data indicative of a characteristic or parameter of the environment.

42. The method of claim 36, further comprising:

initiating an update of the selected wireless power transmission regime.

43. The method of claim 36, further comprising:

initiating, modifying, or terminating a transfer of radiofrequency electromagnetic energy from the antenna to the target device in response to a request originated by the target device or in response to a schedule.