Broadband quardifilar helix with high peak gain on the horizon

• US 20030206143A1
• Filed: 05/03/2002
• Published: 11/06/2003
• Est. Priority Date: 05/03/2002
• Status: Active Grant

• Current Assignee: North South Holdings Incorporated (Spherix Incorporated)
• Original Assignee: Harris Corporation (L3Harris Technologies, Inc.)
• Inventors: Killen, William Dean, Goldstein, Mark Lawrence, Nink, Richard John
• Granted Patent: US 6,812,906 B2
• Time in Patent Office: Days
• US Class Current: 343/895
• CPC Class Codes: H01Q 1/362 for broadside radiating helical antennas
• CPC Class Codes: H01Q 11/08 Helical antennas

Abstract

The invention concerns a quadrifilar helix antenna that has four orthogonal conductive elements helically wound around a common axis. Each of the conductive elements can have between 3 to 7 turns about the common axis at a pitch of between 45 to 65 degrees. Further, each turn has a diameter of about 0.13 wavelengths to 0.27 wavelengths. A feed coupler excites each of the orthogonal conductive elements in phase quadrature at a feed point located at a first end of the antenna adjacent to a ground plane. The resulting antenna can have an axial length of about 2.3 wavelengths to 6.9 wavelengths. Unlike conventional quadrifillar helix antennas, an opposing end of each of the conductive elements distal from the feed point forms an open circuit. The antenna configured as described can have a peak gain on horizon when the common axis is oriented vertically.

Claims

1. A quadrifilar helix antenna, comprising:

four orthogonal conductive elements helically wound around a common axis, each said conductive element comprising between 3 to 7 turns about said common axis at a pitch of between 45 to 65 degrees, each said turn having a diameter of approximately 0.13 wavelengths to 0.27 wavelengths;

a feed coupler exciting each of said orthogonal conductive elements in phase quadrature at a feed point located at a first end of said antenna adjacent to a ground plane;

an opposing end of each of said conductive elements distal from said feed point forming an open circuit; and

wherein said antenna has a peak gain on horizon when said common axis is oriented vertically.

2. The antenna according to claim 1 wherein said antenna has an axial length of about 2.3 wavelengths to 6.9 wavelengths.

3. The antenna according to claim 1 wherein said antenna has an axial length of about 4.2 wavelengths to 4.5 wavelengths.

4. The antenna according to claim 1 wherein said conductive element comprises approximately 5 turns.

5. The antenna according to claim 1 wherein said pitch is approximately 55 degrees.

6. The antenna according to claim 1 wherein each said turn has a diameter of approximately 0.18 wavelengths to 0.2 wavelengths.

7. The antenna according to claim 1 wherein said antenna has a gain of at least 5 dBiC on horizon when said common axis is oriented vertically.

8. The antenna according to claim 1 wherein said antenna has a 3 dB bandwidth of 5% to 8% of a center operating frequency.

9. The antenna according to claim 1 wherein said antenna has an input VSWR of between about 1.0 and 1.5 within an operating bandwidth of between 5% to 8% of a center operating frequency.

10. A quadrifilar helix antenna, comprising:

four orthogonal conductive elements helically wound around a common axis, each said conductive element comprising a plurality of turns about said common axis; and

a feed coupler exciting each of said orthogonal conductive elements in phase quadrature at a feed point located at a first end of said antenna adjacent to a ground plane;

an opposing end of each of said conductive elements distal from said feed point forming an open circuit

11. The antenna according to claim 10 wherein said turns, a turns diameter, and a pitch are selected to provide a gain of at least 5 dBiC on horizon when said common axis is oriented vertically.

12. A quadrifilar helix antenna, comprising:

four orthogonal conductive elements helically wound around a common axis, each said conductive element comprising 3 to 7 turns about said common axis; and

a feed coupler exciting each of said orthogonal conductive elements in phase quadrature at a feed point located at a first end of said antenna adjacent to a ground plane;

an opposing end of each of said conductive elements distal from said feed point forming an open circuit; and

wherein said antenna has a peak gain on horizon when said common axis is oriented vertically.

13. The antenna according to claim 12 wherein said antenna has a peak gain of at least about 5 dBiC.

14. The antenna according to claim 12 wherein said conductive element comprises approximately 5 turns.

15. The antenna according to claim 12 wherein each said turn has a diameter of about 0.13 wavelengths to 0.27 wavelengths.

16. The antenna according to claim 12 wherein each said turn has a diameter of approximately 0.18 wavelengths to 0.2 wavelengths.

17. The antenna according to claim 12 wherein said conductive elements are helically wound around said common axis at a pitch of between 45 to 65 degrees.

18. The antenna according to claim 12 wherein said conductive elements are helically wound around said common axis at a pitch of approximately 55 degrees.

19. The antenna according to claim 12 wherein said antenna has an axial length of 2.3 wavelengths to 6.9 wavelengths.

20. The antenna according to claim 12 wherein an axial length of said antenna is approximately 4.2 wavelengths to 4.5 wavelengths.

21. The antenna according to claim 12 wherein said antenna has an input VSWR of between about 1.0 and 1.5 within an operating bandwidth of between 5% to 8% of a center operating frequency.

22. A quadrifilar helix antenna, comprising:

four orthogonal conductive elements helically wound around a common axis, each said turn having a diameter of about 0.13 wavelengths to 0.27 wavelengths; and

a feed coupler exciting each of said orthogonal conductive elements in phase quadrature at a feed point located at a first end of said antenna adjacent to a ground plane;

an opposing end of each of said conductive elements distal from said feed point forming an open circuit; and

wherein said antenna has a peak gain on horizon when said common axis is oriented vertically.

23. The antenna according to claim 22 wherein said antenna has a peak gain of at least about 5 dBiC.

24. The antenna according to claim 22 wherein said conductive element comprises approximately 3 to 7 turns.

25. The antenna according to claim 22 wherein said conductive element comprises approximately 5 turns.

26. The antenna according to claim 22 wherein each said turn has a diameter of approximately 0.18 wavelengths to 0.2 wavelengths.

27. The antenna according to claim 22 wherein said conductive elements are helically wound around said common axis at a pitch of between 45 to 65 degrees.

28. The antenna according to claim 22 wherein said conductive elements are helically wound around said common axis at a pitch of approximately 55 degrees.

29. The antenna according to claim 22 wherein said antenna has an axial length of 2.3 wavelengths to 6.9 wavelengths.

30. The antenna according to claim 22 wherein an axial length of said antenna is approximately 4.2 wavelengths to 4.5 wavelengths.

31. The antenna according to claim 25 wherein said antenna has an input VSWR of between about 1.0 and 1.5 within an operating bandwidth of between 5% to 8% of a center operating frequency.

32. A quadrifilar helix antenna, comprising:

four orthogonal conductive elements helically wound around a common axis, each said conductive element comprising approximately 5 turns about said common axis at a pitch of approximately 55 degrees, each said turn having a diameter of approximately 0.18 wavelengths to 0.26 wavelengths;

a feed coupler exciting each of said orthogonal conductive elements in phase quadrature at a feed point located at a first end of said antenna adjacent to a ground plane;

an opposing end of each of said conductive elements distal from said feed point forming an open circuit; and

wherein said antenna has a peak gain on horizon when said common axis is oriented vertically.

33. The antenna according to claim 32 wherein said peak gain is at least 2 about 5 dBiC.

34. The antenna according to claim 32 wherein said peak gain is at least 2 about 6.5 dBiC.