Implantable device including multiple communication antennas

• US 20060241724A1
• Filed: 04/20/2005
• Published: 10/26/2006
• Est. Priority Date: 04/20/2005
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Verhoef, William D., Przybyszewski, Piotr, Haubrich, Gregory J., Fuller, Chris C., Twetan, Len D., Dublin, Garry L.
• Granted Patent: US 7,672,731 B2
• Time in Patent Office: Days
• US Class Current: 607/60
• CPC Class Codes: A61N 1/37223 Circuits for electromagnetic coupling
• CPC Class Codes: A61N 1/37229 Shape or location of the implanted or external antenna

Abstract

An implantable device, such as an implantable medical device (IMD) includes at least two radio frequency (RF) antennas and may additionally include an RF communication circuit. The RF antennas are spatially diverse, are disposed adjacent a housing, and are each configured to receive RF signals transmitted to the IMD from a remote RF signal source. The RF communication circuit, if included, is disposed within the housing and is configured to selectively receive the RF signals received by one or more of the spatially diverse RF antennas.

Claims

1. An implantable device, comprising:

a housing; and

at least two radio frequency (RF) antennas disposed adjacent the housing, each RF antenna configured to receive RF signals transmitted to the IMD from a remote RF signal source.

2. The device of claim 1, further comprising:

an RF communication circuit disposed within the housing and configured to selectively receive the RF signals received by one or more of the RF antennas.

3. The device of claim 2, wherein:

the RF communication circuit is further configured to operate at a center frequency, the center frequency having a wavelength; and

the RF antennas are spaced-apart from one another by a distance that is at least one quarter of the center frequency wavelength.

4. The device of claim 2, further comprising:

an antenna switch coupled between each of the RF antennas and the RF communication circuit, the antenna switch configured to receive a switch control signal and operable, in response thereto, to selectively couple the RF communication circuit to one of the RF antennas, whereby one of the RF antennas is an active antenna.

5. The device of claim 2, wherein the RF signals received by the active RF antenna have an RF signal strength, and wherein the IMD further comprises:

a communication controller coupled to receive one or more signals at least representative of the received RF signal strength and operable, upon receipt thereof, to selectively supply the switch control signal to the antenna switch.

6. The device of claim 5, wherein:

the one or more signals are one or more data streams having a level of data integrity; and

the controller is further operable to (i) determine the level of data integrity of the data streams and (ii) selectively supply the switch control signal, based at least in part on the determined data integrity level.

7. The device of claim 1, wherein each of the RF antennas is disposed external to the housing.

8. The device of claim 1, further comprising:

a plurality of feedthroughs extending through the housing, each feedthrough electrically coupled to one of the RF antennas.

9. The device of claim 1, wherein:

the housing comprises two or more electrically conductive housing sections electrically insulated from one another; and

each housing section functions as one of the RF antennas.

10. The IMD of claim 2, wherein:

the RF communication circuit is configured to selectively receive the RF signals received by at least two of the RF antennas; and

the RF communication circuit is further operable to combine the RF signals received by the two or more antennas.

11. The device of claim 1, wherein:

the housing includes at least a first side and an opposing second side; and

half of the RF antennas are disposed on the first side and half of the RF antennas are disposed on the second side.

12. The device of claim 1, wherein at least two of the RF antennas are disposed, one each, on opposing sides of the housing.

13. The device of claim 1, further comprising:

at least two radomes, each radome at least partially surrounding at least one of the RF antennas.

14. The device of claim 1, further comprising:

a physiological therapy supply circuit disposed within the housing and configured to selectively supply therapy pulses;

one or more therapy leads extending through the housing and coupled to receive the therapy pulses from the physiological therapy supply circuit,

wherein at least one of the one or more therapy leads includes one of the RF antennas.

15. The device of claim 2, wherein:

the RF signals are modulated RF signals; and

the RF communication circuit is operable, upon receipt of the modulated signals, to demodulate the modulated RF signals.

16. The device of claim 1, wherein the RF antennas are configured to provide spatial diversity.

17. An implantable medical device (IMD), comprising:

a housing;

at least two spatially diverse radio frequency (RF) antennas, each RF antenna configured receive RF signals transmitted to the IMD from a remote RF signal source and to emit RF signals to one or more remote devices; and

an RF communication circuit disposed within the housing and configured to selectively receive the RF signals received by one or more of the spatially diverse RF antennas and supply the RF signals emitted by one or more of the spatially diverse antennas.

18. The IMD of claim 17, further comprising:

an antenna switch coupled between each of the RF antennas and the RF communication circuit, the antenna switch configured to receive a switch control signal and operable, in response thereto, to selectively couple the RF communication circuit to one of the RF antennas, whereby one of the RF antennas is an active antenna.

19. The IMD of claim 18, wherein the modulated RF signals received by the active RF antenna have an RF signal strength, and wherein the IMD further comprises:

a communication controller coupled to receive one or more signals at least representative of the received RF signal strength and operable, upon receipt thereof, to selectively supply the switch control signal to the antenna switch.

20. The IMD of claim 17, wherein:

the antenna switch is operable to selectively couple the RF communication circuit to two or more of the RF antennas; and

the RF communication circuit is further operable to combine the RF signals received by the two or more spatially diverse antennas.

21. The IMD of claim 17, wherein:

the housing comprises two or more electrically conductive housing sections electrically insulated from one another; and

each housing section functions as one of the spatially diverse RF antennas.

22. The IMD of claim 17, further comprising:

a physiological therapy supply circuit disposed within the housing and configured to selectively supply therapy pulses;

one or more therapy leads extending through the housing and coupled to receive the therapy pulses from the-physiological therapy supply circuit,

wherein at least one of the one or more therapy leads includes one of the spatially diverse RF antennas.