Device and method for reducing interference with adjacent satellites using a mechanically gimbaled asymmetrical-aperture antenna

Patent metadata

Field	Value
Publication number	US-10056673-B2
Application number	US-201514812929-A
Country	US
Kind code	B2
Filing date	Jul 29, 2015
Priority date	Nov 29, 2012
Publication date	Aug 21, 2018
Grant date	Aug 21, 2018

Abstract

Methods, apparatuses, and systems for two-way satellite communication and an asymmetric-aperture antenna for two-way satellite communication are disclosed. In one embodiment, a beam pattern for an asymmetric-aperture antenna is offset in a narrow beamwidth direction, and the offset beam pattern is directed by a mechanical gimbal, with the beam pattern offset made to reduce interference with an adjacent satellite. In additional embodiments, operational areas near the equator are identified for a given offset beam pattern, or a beam pattern offset may be adjusted over time to compensate for movement of the asymmetric-aperture antenna when attached to an airplane, boat, or other mobile vehicle.

First claim

What is claimed is:

1. An antenna for mounting on a mobile vehicle for communicating with a satellite, the antenna comprising:
a radiating surface to produce a beam having an asymmetric antenna pattern, wherein the asymmetric antenna pattern has a narrow-beamwidth direction and a wide-beamwidth direction;
a beam steering apparatus responsive to commands to point the beam in a direction toward the satellite, the beam steering apparatus comprising:
an azimuth adjustment to adjust an azimuth angle of the beam;
an elevation adjustment to adjust an elevation angle of the beam; and
a skew adjustment to adjust a skew angle of the beam, wherein the skew adjustment changes at least one of the azimuth angle or the elevation angle for pointing the beam in the direction toward the satellite; and

control circuitry to provide the commands to the beam steering apparatus, wherein the provided commands are based on a location of the mobile vehicle, and wherein the provided commands further control the azimuth adjustment and the elevation adjustment to compensate for the changes in the at least one of the azimuth angle or the elevation angle due to the skew adjustment, to maintain the pointing of the beam in the direction toward the satellite.

2. The antenna of claim 1 , wherein the satellite is a geostationary satellite on a geostationary arc, and the skew angle is an angle relative to the geostationary arc.

3. The antenna of claim 1 , wherein the skew adjustment adjusts the skew angle of the beam to change a service area of the antenna for communicating with the satellite.

4. The antenna of claim 1 , wherein the skew adjustment adjusts the skew angle of the beam to reduce interference with a second satellite.

5. The antenna of claim 1 , wherein the control circuitry changes the commands in response to movement of at least one of the antenna or the satellite.

6. The antenna of claim 1 , wherein the commands provided to the beam steering apparatus include commands to control the skew adjustment to adjust the skew angle of the beam, and further include commands to control the azimuth adjustment and the elevation adjustment to maintain pointing of the beam in the direction towards the satellite.

7. The antenna of claim 1 , wherein the skew adjustment controls a physical component of the antenna to adjust the skew angle.

8. The antenna of claim 1 , wherein the skew adjustment is a mechanical structure.

9. The antenna of claim 1 , wherein the radiating surface comprises a planar array of radiating elements.

10. The antenna of claim 1 , wherein the skew adjustment adjusts the skew angle over a range of skew angles.

11. A method comprising:
associating an antenna mounted on a mobile vehicle with a satellite for communications, wherein the antenna comprises a radiating surface to produce a beam having an asymmetric antenna pattern with a narrow-beamwidth direction and a wide-beamwidth direction, and a beam steering apparatus to adjust an azimuth angle of the beam, adjust an elevation angle of the beam, and adjust a skew angle of the beam, and wherein adjusting the skew angle changes at least one of the azimuth angle or the elevation angle for pointing the beam in a direction toward the satellite; and
pointing, using the beam steering apparatus, the beam in the direction toward the satellite from a first location of the antenna, the pointing comprising adjusting the azimuth angle, the elevation angle and the skew angle of the beam based on the first location, wherein the pointing further comprises adjusting the at least one of the azimuth angle or the elevation angle to compensate for the changes in the at least one of the azimuth angle or the elevation angle due to adjusting the skew angle, to maintain the pointing of the beam in the direction toward the satellite.

12. The method of claim 11 , further comprising pointing, using the beam steering apparatus, the beam toward the satellite from a second location of the antenna, the pointing from the second location comprising further adjusting the azimuth angle, the elevation angle and the skew angle based on the second location, wherein the further adjusting the azimuth angle and the elevation angle comprises further adjusting the at least one of the azimuth angle or the elevation angle to compensate for the changes in the at least one of the azimuth angle or the elevation angle due to adjusting the skew angle based on the second location, to maintain the pointing of the beam toward the satellite from the second location.

13. The method of claim 11 , wherein the mobile vehicle is an aircraft.

14. The method of claim 11 , wherein the satellite is a geostationary satellite on a geostationary arc, and the skew angle is an angle relative to the geostationary arc.

15. The method of claim 11 , wherein adjustment of the skew angle of the beam changes a service area of the antenna for communicating with the satellite.

16. The method of claim 11 , wherein adjustment of the skew angle of the beam reduces interference with a second satellite.

17. The method of claim 11 , further comprising adjusting the skew angle of the beam and maintaining pointing the beam in the direction of the satellite using the beam steering apparatus.

18. The method of claim 11 , wherein the beam steering apparatus controls a physical component of the antenna to adjust the skew angle.

19. The method of claim 11 , wherein the beam steering apparatus includes a mechanical structure to adjust the skew angle.

20. The method of claim 11 , wherein the radiating surface comprises a planar array of radiating elements.

Assignees

• Viasat Inc

Inventors

• Irvine David H

Classifications

• H01Q3/245 Primary

  in the focal plane of a focussing device · CPC title

• H01Q3/30

  varying the {relative} phase {between the radiating elements of an array (H01Q3/2605, H01Q3/2658, H01Q3/2682, H01Q3/44 take precedence)} · CPC title

• H01Q3/28

  varying the amplitude · CPC title

• H01Q3/08

  for varying two co-ordinates of the orientation · CPC title

• H01Q25/00

  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 title