MULTI-ANTENNA FOR AN IMPLANTABLE MEDICAL DEVICE

• US 20070288066A1
• Filed: 06/09/2006
• Published: 12/13/2007
• Est. Priority Date: 06/09/2006
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Christman, Timothy J., Edwardson, Jason J., Carey, Bart A.
• Granted Patent: US 7,613,522 B2
• Time in Patent Office: Days
• US Class Current: 607/60
• CPC Class Codes: A61N 1/37229 Shape or location of the implanted or external antenna
• CPC Class Codes: H01Q 1/273 Adaptation for carrying or wearing by persons or animals
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 9/16 with feed intermediate between the extremities of the antenna, e.g. centre-fed dipole H01Q9/44 takes precedence

Abstract

A system for enabling telemetry in implantable medical devices is provided. One aspect of this disclosure relates to an implantable medical device having radio-frequency telemetry capabilities. The device includes a housing and electronic circuitry contained within the housing. The device also includes an array of antennas connected to the electronic circuitry. According to various embodiments, the array and circuitry are adapted to facilitate far-field transmission and reception of modulated radio-frequency energy at one or more specified carrier frequencies. Individual antenna elements in the array are connected simultaneously or in a mutually exclusive manner to electronic circuitry having a single transmit/receive antenna port using a switch, according to various embodiments. Individual antenna element geometries are sized to optimize individual antennas each for a different range of operating frequencies, according to various embodiments. Other aspects and embodiments are provided herein.

Claims

1. An implantable medical device, comprising:

a housing;

electronic circuitry within the housing; and

two or more antennas connected to the electronic circuitry, wherein the antennas and circuitry are adapted to facilitate transmission and reception of modulated radio-frequency energy at one or more specified carrier frequencies.

2. The device of claim 1, wherein each the two or more antennas include different antenna element geometries.

3. The device of claim 2, wherein individual antenna element geometries are sized to optimize individual antennas each for a different termination medium.

4. The device of claim 3, wherein a termination medium includes air.

5. The device of claim 3, wherein a termination medium includes muscle tissue.

6. The device of claim 3, wherein a termination medium includes fatty tissue.

7. The device of claim 2, wherein individual antenna element geometries are sized to optimize individual antennas each for a different range of operating frequencies.

8. An implantable medical device, comprising:

a housing;

electronic circuitry within the housing; and

an array of antennas connected to the electronic circuitry, wherein the array and circuitry are adapted to facilitate transmission and reception of modulated radio-frequency energy at one or more specified carrier frequencies.

9. The device of claim 8, wherein each antenna in the array of antennas includes identical antenna element geometries.

10. The device of claim 8, wherein the array includes a photochemically-etched metallization pattern on a planar dielectric substrate.

11. The device of claim 8, wherein individual antenna elements in the array are connected in a mutually exclusive manner to electronic circuitry having a single transmit/receive antenna port using a switch.

12. The device of claim 11, wherein the switch includes a mechanical switch.

13. The device of claim 11, wherein the switch includes an electrical switch.

14. The device of claim 11, wherein a state of the switch is changed to minimize an observed error rate.

15. The device of claim 11, wherein a state of the switch is changed to restore communication upon loss of radio frequency communication.

16. The device of claim 8, wherein individual antenna elements in the array are each connected to electronic circuitry having a single transmit/receive antenna port via inline phase shifting elements, such that each antenna element transmits/receives a proportion of radio-frequency energy to the electronic circuitry with a phase shift.

17. The device of claim 16, wherein the phase shift for each antenna element in the array is fixed to establish a desired shape of a transmit/receive spatial pattern.

18. The device of claim 16, wherein the phase shift for each antenna element in the array is variable and controlled by logic to dynamically alter a shape of a transmit/receive spatial pattern.

19. The device of claim 18, wherein the logic alters relative phase shift of each antenna element according to a fixed sequence of phases.

20. The device of claim 18, wherein the logic alters relative phase shift of each antenna element to minimize an observed error rate.

21. The device of claim 18, wherein the logic alters relative phase shift of at least one antenna element to restore communication upon loss of radio frequency communication.

22. The device of claim 16, wherein the array includes a photochemically-etched metallization pattern on a planar dielectric substrate.

23. The device of claim 8, wherein individual antenna elements in the array are each connected to electronic circuitry having multiple transmit/receive antenna ports, such that each antenna element is capable of operating independently.

24. The device of claim 23, wherein each antenna element in the array is switched by logic according to a fixed sequence of states.

25. The device of claim 23, wherein each antenna element in the array is phase-shifted by logic according to a fixed sequence of states.

26. The device of claim 23, wherein each antenna element in the array is switched by logic to minimize an observed error rate.

27. The device of claim 23, wherein each antenna element in the array is phase-shifted by logic to minimize an observed error rate.

28. The device of claim 23, wherein at least one antenna element in the array is switched by logic to restore communication upon loss of radio frequency communication.

29. The device of claim 23, wherein the array includes a photochemically-etched metallization pattern on a planar dielectric substrate.

30. A method, comprising:

forming an antenna assembly, including forming an array of antennas adapted to facilitate transmission and reception of modulated radio-frequency energy at one or more specified carrier frequencies;

installing the antenna assembly in an implantable medical device; and

connecting the antenna assembly to electronic circuitry within the implantable medical device.

31. The method of claim 30, wherein forming the antenna assembly includes surrounding the antenna array with a dielectric material.

32. The method of claim 31, wherein surrounding the antenna array with a dielectric material includes overmolding the antenna array.

33. The method of claim 31, wherein surrounding the antenna array with a dielectric material includes backfilling with a medical adhesive.

34. The method of claim 30, further comprising:

after installing the antenna assembly in the implantable medical device, surrounding the antenna array with a dielectric material.

35. The method of claim 30, wherein forming an array of antennas includes surrounding at least one antenna with dielectric-embedded passive elements, the passive elements adapted to change shape of a transmit and receive spatial pattern.

36. The method of claim 35, wherein forming the passive elements includes forming passive elements adapted to tune at least one antenna in the array over a specified range of frequencies.