Litzendraht loop antenna and associated methods

• US 20060038730A1
• Filed: 08/19/2004
• Published: 02/23/2006
• Est. Priority Date: 08/19/2004
• Status: Active Grant

• Current Assignee: Harris Corporation (L3Harris Technologies, Inc.)
• Original Assignee: Harris Corporation (L3Harris Technologies, Inc.)
• Inventors: Parsche, Francis Eugene
• Granted Patent: US 7,205,947 B2
• Time in Patent Office: Days
• US Class Current: 343/741
• CPC Class Codes: H01Q 7/04 Screened antennas H01Q7/02, H01Q7/06 take precedence

Abstract

The antenna includes a Litz wire loop having a plurality of individually insulated wires braided together and a plurality of splices therein to define distributed capacitors. A magnetically coupled feed loop is provided within the electrically conductive loop, and a feed structure, such as a coaxial feed line, feeds the magnetically coupled feed loop.

Claims

1. An antenna comprising:

a Litz wire loop including a plurality of wires braided or twisted together and having a plurality of splices therein to define distributed capacitors;

a feed loop adjacent the Litz wire loop; and

a feed structure connected to the feed loop.

2. The antenna according to claim 1 wherein the plurality of wires comprises a plurality of individually insulated wires.

3. The antenna according to claim 1 wherein the Litz wire loop further comprises a plurality of dielectric strands braided or twisted with the plurality of wires.

4. The antenna according to claim 1 wherein the Litz wire loop further comprises an inner dielectric core with the plurality of wires positioned therearound.

5. The antenna according to claim 1 wherein the Litz wire loop comprises served Litz wire.

6. The antenna according to claim 1 wherein the Litz wire loop comprises unserved Litz wire.

7. The antenna according to claim 1 wherein the feed structure comprises a coaxial feed line.

8. The antenna according to claim 1 further comprising a coaxial electrostatic shield surrounding the Litz wire loop.

9. The antenna according to claim 1 wherein the feed loop is within the Litz wire loop and magnetically coupled thereto.

10. The antenna according to claim 1 wherein the plurality of wires comprises a plurality of groups of wires, the wires in a group being braided or twisted together, and the plurality of groups being braided or twisted together.

11. The antenna according to claim 1 wherein the plurality of wires comprises about 1700-1900 strands of insulated wire between about #36 and #40 AWG (American Wire Gauge).

12. An antenna comprising:

a Litz wire loop including a plurality of splices therein;

a magnetically coupled feed loop within the Litz wire loop;

a coaxial electrostatic shield surrounding the Litz wire loop; and

a feed structure to feed the magnetically coupled feed loop.

13. The antenna according to claim 12 wherein the Litz wire loop comprises a plurality of individually insulated wires braided or twisted together.

14. The antenna according to claim 13 wherein the Litz wire loop comprises served Litz wire.

15. The antenna according to claim 13 wherein the Litz wire loop comprises unserved Litz wire.

16. The antenna according to claim 12 wherein the feed structure comprises a coaxial feed line.

17. The antenna according to claim 12 wherein the plurality of splices in the Litz wire loop define distributed capacitors therein.

18. The antenna according to claim 12 wherein the Litz wire comprises a plurality of groups of wires, the wires in a group being braided or twisted together, and the plurality of groups being braided or twisted together.

19. The antenna according to claim 12 wherein the Litz wire comprises about 1700-1900 strands of insulated wire between about #36 and #40 AWG (American Wire Gauge).

20. A method of making an antenna comprising:

forming a Litz wire loop including a plurality of wires braided or twisted together;

providing distributed capacitors by forming a plurality of splices in the Litz wire loop;

providing a feed loop adjacent the Litz wire loop; and

connecting a feed structure to the feed loop.

21. The method according to claim 20 further comprising tuning the frequency of the electrically conductive loop by at least one of breaking and connecting selected wires of the plurality of wires.

22. The method according to claim 20 wherein the plurality of wires comprises a plurality of individually insulated wires.

23. The method according to claim 22 wherein the Litz wire comprises served Litz wire.

24. The method according to claim 22 wherein the Litz wire comprises unserved Litz wire.

25. The method according to claim 20 wherein the feed structure comprises a coaxial feed line.

26. The method according to claim 20 further comprising surrounding the electrically conductive loop with an outer shield.

27. The method according to claim 26 wherein the outer shield comprises a coaxial electrostatic shield.

28. The method according to claim 20 wherein the plurality of wires comprises a plurality of groups of wires, the wires in a group being braided or twisted together, and the plurality of groups being braided or twisted together.

29. The antenna according to claim 20 wherein the plurality of wires comprises about 1800 strands of enameled #38 AWG (American Wire Gauge) wire.

30. A conductive structure comprising:

a Litz wire loop including a plurality of wires braided or twisted together and having a plurality of splices therein to define distributed capacitors; and

at least one coupling loop adjacent the Litz wire loop.

31. The conductive structure according to claim 30 wherein the at least one coupling loop is within the Litz wire loop and magnetically coupled thereto.

32. The conductive structure according to claim 30 wherein the plurality of wires comprises a plurality of individually insulated wires.

33. The conductive structure according to claim 30 wherein the Litz wire loop further comprises a plurality of dielectric strands braided or twisted with the plurality of wires.

34. The conductive structure according to claim 30 wherein the Litz wire loop further comprises an inner dielectric core with the plurality of wires positioned therearound.