Co-located multi-band antenna

• US 7,038,632 B2
• Filed: 11/22/2004
• Issued: 05/02/2006
• Est. Priority Date: 09/14/2001
• Status: Expired due to Fees

• Current Assignee: Raven Antenna Systems, Inc. (Satellite Acquisition Corporation)
• Original Assignee: Andrew Corporation (CommScope Holding Company, Inc.)
• Inventors: Geen, David, Webb, David, Brandau, Ronald
• Primary Examiner(s): Ho, Tan
• Application Number:
  US10/904,674
• Publication Number:
  US 20050110694A1
• Time in Patent Office: 526 Days
• Field of Search: 343/781.P, 343/781.CA
• US Class Current: 343/781.00P
• CPC Class Codes: H01Q 19/027 for compensating or reducing aperture blockage offset feeding H01Q19/132, H01Q19/192
• CPC Class Codes: H01Q 19/17 the primary radiating source comprising two or more radiating elements H01Q19/15, H01Q25/00 take precedence
• CPC Class Codes: H01Q 19/192 with dual offset reflectors
• CPC Class Codes: H01Q 5/45 using two or more feeds in association with a common reflecting, diffracting or refracting device

Abstract

A multi-band reflector antenna having a main reflector, a sub reflector, a first feed and a second feed. The first feed, the sub reflector and the main reflector positioned in a Gregorian optic configuration wherein an output of the first feed is directed to the sub reflector, from the sub reflector to the main reflector and from the main reflector into a first beam. The sub reflector may be shaped to distribute the output of the first feed reflecting off the sub reflector onto the main reflector whereby a central area of the main reflector has a lower illumination than a surrounding outer area of the main reflector and or elongated vertically. The second feed projecting from a hole in the sub reflector is oriented whereby an output of the second feed is directed to the main reflector and from the main reflector into a second beam.

Claims

1. A multi-band reflector antenna, comprising:

a main reflector;

a sub reflector;

a first feed; and

a second feed projecting from a hole in the sub reflector;

the first feed, the sub reflector and the main reflector positioned in a Gregorian optic configuration wherein an output of the first feed is directed to the sub reflector, from the sub reflector to the main reflector and from the main reflector into a first beam;

the sub reflector shaped to distribute the output of the first feed reflecting off the sub reflector onto the main reflector, whereby a central area of the main reflector has a lower illumination than a surrounding outer area of the main reflector;

the second feed oriented whereby an output of the second feed is directed to the main reflector and from the main reflector into a second beam.

2. The antenna of claim 1, wherein a phase center of the second feed is positioned proximate a focal region of the main reflector.

3. The antenna of claim 1, wherein the second feed is disposed within the hole.

4. The antenna of claim 1, wherein the second feed extends through the hole into a focal region of the main reflector.

5. The antenna of claim 1, wherein the sub reflector is in an offset configuration with respect to the main reflector.

6. The antenna of claim 1, wherein a reflective surface of the sub reflector is not frequency selective.

7. The antenna of claim 1, wherein the second feed is one of a horn antenna, a polyrod antenna, a helix antenna and an antenna array.

8. The antenna of claim 1, further including a primary third feed proximate the sub reflector.

9. The antenna of claim 8, wherein the primary third feed has a minimum scan of greater than 3 degrees.

10. The antenna of claim 8, wherein the primary third feed is positioned within a notch formed in the sub reflector.

11. The antenna of claim 10, wherein the notch is configured via one of a numerically tabulated and an analytic function that varies a rim feed angle of the sub reflector.

12. The antenna of claim 8, further including a secondary third feed adjacent the sub reflector on a side of the sub reflector opposite from the primary third feed.

13. The antenna of claim 8, further including a secondary third feed adjacent the primary third feed.

14. The antenna of claim 1, further including a third feed disposed in a second hole in the sub reflector, adjacent the second feed.

15. The antenna of claim 14, wherein the third feed and the second feed are scanned apart by between 2 and 8 degrees.

16. The antenna of claim 1, wherein the first beam and the second beam are nominally coincident with each other.

17. The antenna of claim 1, wherein the first beam and the second beam are scanned apart by at least 2 degrees.

18. The antenna of claim 1, wherein the second feed has a gain of 14 dBi or less.

19. The antenna of claim 1, wherein the sub reflector is dimensioned to be at least 8 wavelengths of a midband frequency of the first feed.

20. The antenna of claim 1, wherein the second feed is configured to simultaneously operate at two different frequency bands.

21. The antenna of claim 1, further including a third feed disposed proximate the first feed.

22. The antenna of claim 21, wherein the third feed is scanned away from the first feed between 2 and 8 degrees.

23. A multi-band reflector antenna, comprising:

a main reflector;

a sub reflector;

a first feed; and

a second feed projecting from a hole in the sub reflector;

the first feed, the sub reflector and the main reflector positioned in a Gregorian optic configuration wherein an output of the first feed is directed to the sub reflector, from the sub reflector to the main reflector and from the main reflector into a first beam;

the second feed oriented whereby an output of the second feed is directed to the main reflector and from the main reflector into a second beam;

the sub reflector shaped to have an elevation dimension that is greater than an azimuth dimension.

24. The antenna of claim 23, wherein the second feed has a gain of more than 14 dBi.

25. The antenna of claim 23, wherein the sub reflector is dimensioned to be less than 8 wavelengths of a midband frequency of the second radio frequency feed.

26. The antenna of claim 23, wherein a phase center of the second feed is positioned proximate a focal region of the main reflector.

27. The antenna of claim 23, wherein the second feed is disposed within the hole.

28. The antenna of claim 23, wherein the second feed extends through the hole into a focal region of the main reflector.

29. The antenna of claim 23, wherein the sub reflector is in an offset configuration with respect to the main reflector.

30. The antenna of claim 23, wherein a reflective surface of the sub reflector is not frequency selective.

31. The antenna of claim 23, wherein the second feed is one of a horn antenna, a polyrod antenna, a helix antenna and an antenna array.

32. The antenna of claim 23, further including a primary third feed proximate the sub reflector.

33. The antenna of claim 32, wherein the primary third feed has a scan of greater than 4 degrees.

34. The antenna of claim 32, wherein the primary third feed is positioned within a notch formed in the sub reflector.

35. The antenna of claim 34, wherein the notch is configured via one of a numerically tabulated and an analytic function that varies a rim feed angle of the sub reflector.

36. The antenna of claim 34, further including a secondary third feed adjacent the sub reflector on a side of the sub reflector opposite from the primary third feed.

37. The antenna of claim 34, further including a secondary third feed adjacent the primary third feed.

38. The antenna of claim 23, further including a third feed disposed in the hole, adjacent the second feed.

39. The antenna of claim 23, wherein the first beam and the second beam are nominally coincident with each other.

40. The antenna of claim 23, wherein the first beam and the second beam are scanned apart by at least 2 degrees.

41. The antenna of claim 23, wherein the second feed is configured to simultaneously operate at two different frequency bands.