Mechanically steered antenna with improved efficiency

Patent metadata

Field	Value
Publication number	US-11069973-B1
Application number	US-202015931017-A
Country	US
Kind code	B1
Filing date	May 13, 2020
Priority date	May 13, 2020
Publication date	Jul 20, 2021
Grant date	Jul 20, 2021

Abstract

Technologies directed to a mechanically steered antenna with improved efficiency are described. One antenna includes a first reflector, a second reflector, and an antenna feed element. The second reflector is located on a reflecting side of the first reflector. The second reflector is offset from the first reflector. The second reflector receives an electromagnetic signal from the antenna feed element and outputs an inverted electromagnetic signal corresponding to the electromagnetic signal. The first reflector receives the inverted electromagnetic signal and outputs a collimated beam corresponding to the inverted electromagnetic signal. The antenna further includes a mechanism coupled to the first reflector. The mechanism rotates the first reflector about a first axis. The first axis is along a direction of the inverted electromagnetic signal.

First claim

What is claimed is:

1. A mechanically-steered antenna system comprising:
a support structure;
a parabolic reflector coupled to the support structure;
a planar sub-reflector coupled to the support structure and located on a reflecting side of the parabolic reflector and offset from a paraboloid axis of the parabolic reflector, the parabolic reflector having a paraboloid shape, and the paraboloid axis being an axis of symmetry of the paraboloid shape;
a feed horn coupled to the support structure, wherein:
the planar sub-reflector receives a radio frequency (RF) signal as a first conical beam from the feed horn and outputs an inverted RF signal as a second conical beam, the inverted RF signal corresponding to the RF signal;
the parabolic reflector receives the inverted RF signal and outputs a collimated beam along the paraboloid axis, the collimated beam corresponding to the inverted RF signal; and
the feed horn receives a second RF signal via the planar sub-reflector; and

a first gimbal mechanism coupled to the parabolic reflector, wherein the first gimbal mechanism rotates the parabolic reflector about a first axis to adjust at least an azimuthal angle of the collimated beam, the first axis being an axis of symmetry of the second conical beam between the parabolic reflector and the planar sub-reflector.

2. The mechanically-steered antenna system of claim 1 , further comprising a second gimbal mechanism coupled to the parabolic reflector, the feed horn, and the planar sub-reflector, wherein the second gimbal mechanism rotates the parabolic reflector, the feed horn, and the planar sub-reflector as a single unit about a second axis to adjust an elevation angle of the collimated beam, wherein the second gimbal mechanism comprises a rotary joint that is part of a path of the RF signal and the second RF signal, and wherein the first gimbal mechanism is not part of the path.

3. An apparatus comprising:
a first reflector;
an antenna feed element;
a second reflector located on a reflecting side of the first reflector and offset from the first reflector, the second reflector receives an electromagnetic signal from the antenna feed element and outputs an inverted electromagnetic signal corresponding to the electromagnetic signal, wherein the first reflector receives the inverted electromagnetic signal directly from the second reflector, and outputs a collimated beam corresponding to the inverted electromagnetic signal; and
a mechanism coupled to the first reflector, the mechanism rotates the first reflector about a first axis, the first axis being along a direction of the inverted electromagnetic signal between the second reflector and the first reflector.

4. The apparatus of claim 3 , wherein the first reflector is a parabolic reflector, and wherein the second reflector is a planar reflector, and wherein the antenna feed element is a feed horn.

5. The apparatus of claim 4 , wherein a ratio of a focal length of the first reflector to a diameter of the first reflector is greater than 0.5.

6. The apparatus of claim 3 , wherein the antenna feed element is a multi-element feed.

7. The apparatus of claim 3 , further comprising a second mechanism configured to rotate the first reflector, the antenna feed element, the second reflector, and the mechanism about a second axis, the second axis being different than the first axis.

8. The apparatus of claim 7 , wherein the antenna feed element is configured to receive a second electromagnetic signal via the second reflector, and wherein the second mechanism receives the second electromagnetic signal from the antenna feed element.

9. The apparatus of claim 3 , wherein the mechanism rotates the first reflector by a first angle to steer the collimated beam and a second mechanism rotates first reflector, the second reflector, and the antenna feed as a single unit by a second angle to steer the collimated beam, the second angle being different than the first angle.

10. The apparatus of claim 9 , wherein the first angle is an azimuthal angle and the second angle is an elevation angle.

11. The apparatus of claim 3 , wherein:
the first reflector is configured to receive a second electromagnetic signal and output a third electromagnetic signal to the second reflector, the third electromagnetic signal corresponding to the second electromagnetic signal;
the second reflector is configured to receive the third electromagnetic signal and output a second inverted electromagnetic signal to the antenna feed element, the second inverted electromagnetic signal corresponding to the third electromagnetic signal; and
a path of the second inverted electromagnetic signal does not include the mechanism.

12. The apparatus of claim 3 , wherein the apparatus is disposed on a first plane and the mechanism and a second mechanism are configured to direct the collimated beam in a half-space above the first plane, the half-space comprising the mechanism and the second mechanism, and wherein the second mechanism is configured to rotate the first reflector, the antenna feed element, and the second reflector as a single unit about a second axis.

13. The apparatus of claim 3 , wherein the second reflector is fixed with respect to the antenna feed element.

14. The apparatus of claim 3 , wherein a diameter of the second reflector is less than a diameter of the first reflector.

15. A reflecting antenna comprising:
a support structure;
a first reflector coupled to the support structure;
a second reflector coupled to the support structure, the second reflector having a diameter which is less than a diameter of the first reflector, and the second reflector being offset from the first reflector;
a feed element coupled to the support structure and disposed in proximity to the second reflector, the feed element to provide a first signal to the second reflector, and the second reflector to provide an inverted signal directly to the first reflector;
a first mechanism coupled to the first reflector, the first mechanism being configured to rotate the first reflector about a first axis, the first axis being along a direction of the inverted signal between the first reflector and the second reflector; and
a second mechanism coupled to the support structure, the second mechanism being configured to rotate the support structure about a second axis.

16. The reflecting antenna of claim 15 , wherein:
the feed element is configured to provide the first signal from a transmitter to the second reflector as a first conical beam;
the second reflector is configured to output the inverted signal corresponding to the first signal;
the first reflector is configured to output a collimated beam along an optical axis of the first reflector, the collimated beam corresponding to the inverted signal; and
the feed element is further configured to receive a second signal via the second reflector.

17. The reflecting antenna of claim 16 , wherein the first axis is along a direction of the inverted signal from the second reflector to the first reflector.

18. The reflecting antenna of claim 16 , wherein the first mechanism comprises a first gimbal mechanism and the second mechanism comprises a second gimbal mechanism, wherein the second mechanism is part of a path of the first signal and the second signal, and wherein the first mechanism is not part of the path.

19. The reflecting antenna of claim 15 , wherein the first reflector is a parabolic reflector, wherein the second reflector is a planar reflector, and wherein the feed element is a feed horn.

Assignees

• Amazon Tech Inc

Inventors

• Veysoglu Murat
• Ma ji-fu
• Weng Jeffrey

Classifications

• H01Q19/192

  with dual offset reflectors · CPC title

• H01Q19/132

  Horn reflector antennas; Off-set feeding · CPC title

• H01Q3/20 Primary

  wherein the primary active element is fixed and the reflecting device is movable · CPC title

• H01Q3/10 Primary

  to produce a conical or spiral scan · CPC title