Integrated dual band H-field shielded loop antenna and E-field antenna

• US 6,924,773 B1
• Filed: 09/30/2004
• Issued: 08/02/2005
• Est. Priority Date: 09/30/2004
• Status: Active Grant

• Current Assignee: Medos International Sarl (Johnson & Johnson)
• Original Assignee: Codman Neuro Sciences Sarl
• Inventors: Paratte, Blaise
• Primary Examiner(s): LE, HOANGANH T
• Application Number:
  US10/955,677
• Time in Patent Office: 306 Days
• Field of Search: H01/Q02.1/00, 343/728, 343/842, 343/885, 343/741, 343/744, 343/748, 343/725, 343/729
• US Class Current: 343/728
• CPC Class Codes: H01Q 7/04 Screened antennas H01Q7/02, H01Q7/06 take precedence
• CPC Class Codes: H01Q 9/30 with feed to end of elongated active element, e.g. unipole H01Q9/44 takes precedence

Abstract

A dual band antenna system that combines into a single integrated device an H-field shielded loop antenna and an E-field antenna. The system includes an unshielded section bounded on each end by first and second shielded sections, respectively. Input frequency filters are electrically connected to the first shielded section to selectively pass one of a first radio frequency signal or a second radio frequency signal through the first shielded section. Output frequency filters electrically connected to the unshielded section for switching between two paths of transmission and associated modes of operation: (i) a first mode (operating as an H-field antenna) in which an H-field transmission pattern is generated in the first and second shielded sections; and (ii) a second mode (operating as an E-field antenna) wherein an E-field is radiated via the E-field antenna.

Claims

1. An integrated dual band antenna system comprising:

an H-field antenna comprising;

(i) a first shielded section having a first end and an opposite second end, the first end of the first shielded section being adapted to receive one of a first radio frequency signal or a second radio frequency signal different than the first radio frequency signal;

(ii) a second shielded section having a first end and an opposite second end; and

(iii) an unshielded section disposed between the second ends of the first and second shielded sections forming an unshielded gap;

a first input frequency filter electrically connected to the first end of the first shielded section, the first input frequency filter passing therethrough the first radio frequency signal;

a second input frequency filter electrically connected to the first end of the first shielded section, the second input frequency filter passing therethrough the second radio frequency signal;

a first output frequency filter electrically connected to the unshielded section, the first input frequency filter and first output frequency filter being matched to one another so as to pass therethrough the first radio frequency signal;

a second output frequency filter electrically connected to the unshielded section, the second input frequency filter and second output frequency filter being matched to one another so as to pass therethrough the second radio frequency signal; and

an E-field antenna electrically connected to the second output frequency filter;

the integrated dual band antenna operates in a first mode wherein the first radio frequency signal passes through the first input frequency filter, the first shielded section, the first output frequency filter, the second shielded section and generates an H-field transmission pattern in both the first and the second shielded sections;

the integrated dual band antenna operates in a second mode wherein the second radio frequency signal passes through the second input frequency filter, the first shielded section, the second output frequency filter and radiates an E-field via the E-field antenna.

2. The system in accordance with claim 1, wherein the second radio frequency signal is substantially greater than the first radio frequency signal.

3. The system in accordance with claim 2, wherein the second radio frequency signal is a wireless communication signal, while the first radio frequency signal is at least one of a telemetry, transcutaneous energy transfer or data signal.

4. The system in accordance with claim 3, wherein the second radio frequency signal is in the range of approximately 1 GHz to approximately 3 GHz, while the first radio frequency signal is in the range of approximately 9 kHz to approximately 100 MHz.

5. The system in accordance with claim 2, wherein the first input frequency filter and first output frequency filter are low pass or band pass filters, while the second input frequency filter and second output frequency filter are high pass or band pass filters.

6. The system in accordance with claim 1, further comprising a wireless interface device for receiving via wireless communication the radiated second radio frequency signal.

7. The system in accordance with claim 1, further comprising an implantable medical device for receiving via telemetry communication the first radio frequency signal.

8. The system in accordance with claim 1, wherein the filters comprise passive components.

9. The system in accordance with claim 8, wherein the first output frequency filter is an inductor and the second output frequency filter is a capacitor.

10. A method for operating an integrated dual band antenna having an H-field shielded loop antenna and an E-field antenna including (i) a first shielded section having a first end and an opposite second end, the first end of the first shield section being adapted to receive one of a first radio frequency signal and a second radio frequency signal different than the first radio frequency signal;

(ii) a second shielded section having a first end and an opposite second end; and

(iii) an unshielded section disposed between the second ends of the first and second shielded sections forming an unshielded gap, the method comprising the steps of;

selecting as input to the first shielded section one of the first radio frequency signal or the second radio frequency signal;

transmitting the selected one of the first radio frequency signal or the second radio frequency signal through the first shielded section; and

within the unshielded section of the loop antenna, switching of transmission paths so as to operate in a first mode the H-field shielded loop antenna or in a second mode the E-field antenna.

11. The method in accordance with claim 10, wherein the selecting step comprises passing the first radio frequency signal through a first input frequency filter electrically connected to the first end of the first shielded section.

12. The method in accordance with claim 11, wherein the switching step comprises passing the first radio frequency signal through a first output frequency filter matching the first input frequency filter, the first output frequency filter being electrically connected to the unshielded section.

13. The method in accordance with claim 12, wherein the first input frequency filter and the first output frequency filter are low pass or band pass filters.

14. The method in accordance with claim 12, further comprising guiding the first radio frequency signal that has passed through the first output frequency filter into the second shielded section and generating an H-field transmission pattern in the first and second shielded sections.

15. The method in accordance with claim 10, wherein the selecting step comprises passing the second radio frequency signal through a second input frequency filter electrically connected to the first end of the first shielded section.

16. The method in accordance with claim 15, wherein the switching step comprises passing the second radio frequency signal through a second output frequency filter matching the second input frequency filter, the second output frequency filter being connected between the unshielded section and the E-field antenna.

17. The method in accordance with claim 16, wherein the second input frequency filter and the second output frequency filter are high pass or band pass filters.

18. The method in accordance with claim 16, further comprising radiating through the E-field antenna the second radio frequency signal after passing through the second output frequency filter.

19. The method in accordance with claim 16, wherein the second input frequency filter and the second output frequency filter comprise passive components.

20. The method in accordance with claim 19, wherein the first output frequency filter is an inductor and the second output frequency filter is a capacitor.