Wireless midfield systems and methods

• US 10,039,924 B2
• Filed: 05/25/2017
• Issued: 08/07/2018
• Est. Priority Date: 09/16/2013
• Status: Active Grant

• Current Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford Management Co.)
• Original Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford Management Co.)
• Inventors: Poon, Ada Shuk Yan, Yeh, Alexander, Tanabe, Yuji, Ho, John, Kim, Sanghoek
• Primary Examiner(s): Gedeon, Brian T
• Application Number:
  US15/605,222
• Publication Number:
  US 20170259071A1
• Time in Patent Office: 439 Days
• Field of Search: None
• CPC Class Codes: A61B 2560/0219 of externally powered implanted units
• CPC Class Codes: A61B 5/0008 Temperature signals
• CPC Class Codes: A61B 5/0013 Medical image data A61B1/00011, A61B6/56, A61B8/56 take precedence
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/0084 for introduction into the body, e.g. by catheters A61B5/1459 takes precedence
• CPC Class Codes: A61B 5/01 Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/026 Measuring blood flow A61B3/1233, A61B3/1241 take precedence
• CPC Class Codes: A61B 5/14503 invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors A61B5/1459, A61B5/1464, A61B5/1473, A61B5/1482, A61B5/14865 take precedence
• CPC Class Codes: A61B 5/14539 for measuring pH
• CPC Class Codes: A61B 5/14542 for measuring blood gases A61B5/14551 takes precedence
• CPC Class Codes: A61B 5/24 Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
• CPC Class Codes: A61B 5/686 Permanently implanted devices, e.g. pacemakers, other stimulators, biochips A61B5/6861 takes precedence
• CPC Class Codes: A61H 1/008 Apparatus for applying pressure or blows almost perpendicular to the body or limb axis, e.g. chiropractic devices for repositioning vertebrae, correcting deformation
• CPC Class Codes: A61H 2201/1207 with electric or magnetic drive
• CPC Class Codes: A61H 23/004 With mechanical drive, e.g. spring mechanism or vibrating unit being hit for starting vibration and then applied to the body of a patient
• CPC Class Codes: A61M 2205/8206 battery-operated
• CPC Class Codes: A61M 31/002 Devices for releasing a drug at a continuous and controlled rate for a prolonged period of time artificial gland structures or devices A61F2/022; intra-uterine contraceptive devices A61F6/14; tampons for introducing into the vagina A61F13/20, A61L15/00; suppositories or bougies for intra-vaginal or intra-uterine application A61K9/02; physical forms of medicinal preparations for sustained or differential drug release A61K9/20, A61K9/50
• CPC Class Codes: A61M 5/14276 specially adapted for implantation
• CPC Class Codes: A61N 1/0534 Electrodes for deep brain stimulation
• CPC Class Codes: A61N 1/0551 : Spinal or peripheral nerve electrodes
• CPC Class Codes: A61N 1/056 : Transvascular endocardial electrode systems
• CPC Class Codes: A61N 1/3601 : of respiratory organs
• CPC Class Codes: A61N 1/3605 : Implantable neurostimulators for stimulating central or peripheral nerve system
• CPC Class Codes: A61N 1/36125 : Details of circuitry or electric components
• CPC Class Codes: A61N 1/36139 : with automatic adjustment
• CPC Class Codes: A61N 1/3629 : in combination with non-electric therapy
• CPC Class Codes: A61N 1/365 : controlled by a physiological parameter, e.g. heart potential evoked response A61N1/371
• CPC Class Codes: A61N 1/37211 : Means for communicating with stimulators
• CPC Class Codes: A61N 1/37229 : Shape or location of the implanted or external antenna
• CPC Class Codes: A61N 1/3756 : Casings with electrodes thereon, e.g. leadless stimulators
• CPC Class Codes: A61N 1/3787 : from an external energy source
• CPC Class Codes: A61N 5/0601 : Apparatus for use inside the body
• CPC Class Codes: A61N 7/00 : Ultrasound therapy lithotripsy A61B17/22, A61B17/225; massage using supersonic vibration A61H23/00 ; using ultrasound for introducing media into the body A61M37/0092
• CPC Class Codes: H01Q 1/273 : Adaptation for carrying or wearing by persons or animals
• CPC Class Codes: H01Q 9/0407 : Substantially flat resonant element parallel to ground plane, e.g. patch antenna dipole H01Q9/285; monopole H01Q9/40
• CPC Class Codes: H02J 2310/23 : The load being a medical device, a medical implant, or a life supporting device
• CPC Class Codes: H02J 50/005 : Mechanical details of housing or structure aiming to accommodate the power transfer means, e.g. mechanical integration of coils, antennas or transducers into emitting or receiving devices
• CPC Class Codes: H02J 50/10 : using inductive coupling
• CPC Class Codes: H02J 50/20 : using microwaves or radio frequency waves
• 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 7/00034 : Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge

Abstract

Implantable devices and/or sensors can be wirelessly powered by controlling and propagating electromagnetic waves in a patient'"'"'s tissue. Such implantable devices/sensors can be implanted at target locations in a patient, to stimulate areas such as the heart, brain, spinal cord, or muscle tissue, and/or to sense biological, physiological, chemical attributes of the blood, tissue, and other patient parameters. The propagating electromagnetic waves can be generated with sub-wavelength structures configured to manipulate evanescent fields outside of tissue to generate the propagating waves inside the tissue. Methods of use are also described.

Claims

1. A wireless power transfer system, comprising:

an external transmitter configured to transmit wireless power by manipulating evanescent fields outside of tissue to generate propagating fields inside the tissue and thereby generate a spatially focused field inside the tissue; and

an implantable device configured to receive the wireless power from the external transmitter, the implantable device including at least one sensor or stimulator configured to sense a parameter of the tissue or apply stimulation to the tissue.

2. The system of claim 1, wherein the external transmitter includes a signal generator

configured to concurrently provide respective excitation signals to multiple coupling structures to generate evanescent fields and transmit the wireless power.

3. The system of claim 2, wherein the external transmitter includes a controller

configured to adjust a phase of at least one of the excitation signals to adjust a focus of the field in the tissue.

4. The system of claim 2, wherein the external transmitter includes a controller

configured to adjust an amplitude of at least one of the excitation signals to adjust a focus of the field in tissue.

5. The system of claim 2, wherein the external transmitter is configured to adjust a focus of the field in tissue based on information received from the implantable device.

6. The system of claim 5, wherein the information includes temperature information, image information, implantation depth information, and tissue health information.

7. The system of claim 1, wherein the implantable device is configured to be implanted on, in, or near one or more of a heart, brain, spinal cord, or muscle tissue of a tongue.

8. The system of claim 1, wherein the external transmitter is configured to transmit the wireless power as a midfield propagating wave, including using a magnetic field perpendicular to the wave and parallel to an interface of the tissue.

9. The system of claim 8, wherein the wireless power signal includes a signal in the range of 300 MHz to 3 GHz.

10. The system of claim 1, wherein the external transmitter includes multiple subwavelength structures configured to transmit the wireless power.

11. The system of claim 1, wherein the external transmitter is configured to update a transmission characteristic of the wireless power based on information about a magnitude of energy received at the implanted module from the external transmitter.

12. An apparatus configured to transfer wireless power through body tissue, the apparatus comprising:

multiple coupling structures configured to generate an evanescent field; and

an excitation circuit configured to generate and provide respective excitation signals to the multiple coupling structures to manipulate evanescent fields outside of tissue and to thereby generate a focused propagating field inside the tissue.

13. The apparatus of claim 12, wherein the multiple coupling structures are disposed on a common substrate.

14. The apparatus of claim 12, wherein the excitation circuit is configured to generate and provide the respective excitation signals in the range of 300 MHz to 3 GHz.

15. The apparatus of claim 12, wherein the multiple coupling structures include at least one of a patch structure, a slot structure, a cross slot structure, a circular slot structure, and a half-slot structure.

16. The apparatus of claim 12, wherein the apparatus is configured to initiate a patient therapy by exciting the multiple coupling structures to generate the focused propagating field inside the tissue such that a portion of the propagating field reaches an implanted receiver device that is responsive to the field and is configured to deliver the patient therapy.

17. The apparatus of claim 12, wherein the excitation circuit is configured to change an amplitude or phase characteristic of at least one of the respective excitation signals to adjust a focus of the propagating field inside the tissue.

18. A method for wirelessly powering an implanted device using a mid-field coupler device, the method comprising:

exciting at least one coupling structure in the mid-field coupler device using an excitation signal;

transmitting a wireless power signal from the at least one excited coupling structure, the transmitting including manipulating evanescent fields outside of a patient'"'"'s body and thereby generating electromagnetic waves propagating inside the patient'"'"'s body;

receiving, at the implanted device, at least a portion of the wireless power signal transmitted by the mid-field coupler device; and

in response to receiving the portion of the wireless power signal, at least one of;

applying an electrostimulation therapy to the patient using the implanted device, and

sensing a patient parameter using a sensor coupled to the implanted device.

19. The method of claim 18, wherein the transmitting the wireless power signal includes transmitting a signal in the range of 300 MHz to 3 GHz.

20. The method of claim 18, wherein the applying the electrostimulation therapy to the patient using the implanted device includes using a portion of the received wireless power signal, and wherein the sensing the patient parameter using the sensor includes powering the sensor using a portion of the received wireless power signal.

21. The method of claim 18, further comprising wirelessly receiving device usage information at the mid-field coupler device from the implanted device, the device usage information including information about the electrostimulation therapy and/or about the patient parameter.