Multibeam antenna

• US 6,864,850 B2
• Filed: 03/22/2002
• Issued: 03/08/2005
• Est. Priority Date: 11/15/1996
• Status: Expired due to Fees

• Current Assignee: Yagi Antenna Inc.
• Original Assignee: Yagi Antenna Co., Ltd. (Hitachi, Ltd.)
• Inventors: Higuchi, Hirofumi, Imaizumi, Hiroaki, Manabe, Ryotaro, Sakauchi, Koji, Hagiwara, Shuji
• Primary Examiner(s): Wimer, Michael C.
• Application Number:
  US10/102,779
• Publication Number:
  US 20020097187A1
• Time in Patent Office: 1,082 Days
• Field of Search: 343/753, 343/776, 343/783, 343/786, 343/895
• US Class Current: 343/776
• CPC Class Codes: H01Q 1/247 with frequency mixer, e.g. for direct satellite reception or Doppler radar
• CPC Class Codes: H01Q 11/08 Helical antennas
• CPC Class Codes: H01Q 13/065 provided with a flange or a choke
• CPC Class Codes: H01Q 19/12 wherein the surfaces are concave H01Q19/18 takes precedence
• 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 21/245 provided with means for varying the polarisation polarising devices H01Q15/24; tracking by comparing linear polarisation compounds G01S3/146; reducing depolarisation effects H04B7/00; polarisation diversity H04B7/10
• CPC Class Codes: H01Q 25/00 Antennas or antenna systems providing at least two radiating patterns arrangements for changing or varying the orientation or the shape of the directional pattern H01Q3/00
• CPC Class Codes: H01Q 25/007 using two or more primary active elements in the focal region of a focusing device for operation on different wavebands H01Q5/22
• CPC Class Codes: H01Q 3/18 wherein the primary active element is movable and the reflecting device is fixed
• CPC Class Codes: H01Q 5/45 using two or more feeds in association with a common reflecting, diffracting or refracting device

Abstract

When a converter 14 is rotated via a rotation mechanism 17, the arrangement inclination angle of two primary radiators 15a and 15b can be adjusted in the range of 0 to 20 deg. with respect to an axis which is in parallel with the ground. Also the reception polarization angle due to probes of the primary radiators 15a and 15b can be adjusted in the range of 0 to 20 deg. while maintaining a preset difference in polarization angle among the satellites. Therefore, the arrangement inclination angle of the primary radiators 15a and 15b for respectively receiving signals from the two satellites, and the reception polarization angle in the primary radiators 15a and 15b can be simultaneously easily adjusted by rotating the converter 14 via the rotation mechanism 17.

Claims

1. A primary radiator for a multibeam antenna for receiving micro waves from geostationary satellites, comprising:

plural adjacent primary radiator aperture for receiving microwaves having wavelengths in the same band, each aperture provided with an outer peripheral wall; and

at least two walls having the same height, which are disposed so as to commonly surround said plural apertures,

wherein the at least two walls define therebetween a choke having a depth of about one quarter of a center wavelength of said received microwaves in said band; and

wherein a height of the outer peripheral wall of each aperture is not greater than the height of the at least two surrounding walls.

2. The primary radiator according to claim 1, further comprises dielectric members disposed in each of said primary radiator apertures for focusing said microwaves therein.

3. The primary radiator according to claim 1, further comprises helical antennas disposed in each of said primary radiator apertures.

4. A converter for receiving microwaves from satellites, wherein the primary radiators according to claim 1 is integrated with a main unit of said converter.

5. A converter for receiving microwaves from satellites, wherein the primary radiator according to claim 2 is integrated with a main unit of said converter.

6. A converter for receiving microwaves from satellites, wherein the primary radiator according to claim 3 is integrated with a main unit of said converter.

7. A primary radiator for a multibeam antenna for receiving micro waves from geostationary satellites, comprising:

plural adjacent primary radiator apertures for receiving microwaves having wavelengths in the same band, each aperture provided with an outer peripheral wall having a first height of about one quarter of a center wavelength of said received microwaves in the band; and

a wall member having the first height, which is disposed so as to commonly surround said plural apertures.

8. The primary radiator according to claim 7, further comprises dielectric members disposed in each of said primary radiator apertures for focusing said microwaves therein.

9. The primary radiator according to claim 7, further comprises helical antennas disposed in each of said primary radiator apertures.

10. A converter for receiving microwaves from satellites, wherein the primary radiator according to claim 7 is integrated with a main unit of said converter.

11. A converter for receiving microwaves from satellites, wherein the primary radiator according to claim 8 is integrated with a main unit of said converter.

12. A converter for receiving microwaves from satellites, wherein the primary radiator according to claim 9 is integrated with a main unit of said converter.