ANTENNA BEAM CONTROL ELEMENTS, SYSTEMS, ARCHITECTURES, AND METHODS FOR RADAR, COMMUNICATIONS, AND OTHER APPLICATIONS

• US 20130069813A1
• Filed: 01/07/2011
• Published: 03/21/2013
• Est. Priority Date: 01/08/2010
• Status: Active Grant

• Current Assignee: Obstacle Collision Avoidance System AS (Vestas Wind Systems A/S)
• Original Assignee: Obstacle Collision Avoidance System AS (Vestas Wind Systems A/S)
• Inventors: Vangen, Knut, Pleym, Jan
• Granted Patent: US 9,007,254 B2
• Time in Patent Office: Days
• US Class Current: 342/1
• CPC Class Codes: H01Q 17/00 Devices for absorbing waves radiated from an antenna; Combinations of such devices with active antenna elements or systems
• CPC Class Codes: H01Q 19/021 Means for reducing undesirable effects
• CPC Class Codes: H01Q 19/10 using reflecting surfaces
• CPC Class Codes: H01Q 19/104 using a substantially flat reflector for deflecting the radiated beam, e.g. periscopic antennas periscopic fed Cassegrain antennas H01Q19/191; passive relays H04B7/145
• CPC Class Codes: H01Q 21/20 the units being spaced along or adjacent to a curvilinear path slotted waveguide arrays H01Q21/005; circularly or helically slotted waveguides H01Q21/0062

Abstract

The present invention provides, among other things, antenna beam control devices, systems, architectures, and methods for radar and other applications, such as wireless communications, etc., to improve transmit and/or receive performance of the devices and systems employing such antennas by deploying beam control elements (20) to increase antenna gain at an angle less than a first angle relative to the antenna gain at angle greater than a first angle. Beam control elements are deployed in combination with the one or more antennas (12) in various systems of the present invention, such that the impact of reflected radiation from wind mill, communication, or other towers supporting the system or other nearby structures, as well as radiation from nearby wireless communication networks is decreased to an acceptable level. The beam control elements can include absorbing and reflective material and can be placed in the antenna near field to minimize costs.

Claims

1. An apparatus comprising:

at least one antenna, the antenna being a phased array where the antenna is configured to steer the radiation both azimuthally and by elevation; and

,

a beam control element positioned along a perimeter of the at least one antenna at a first azimuth angle relative to an azimuth reference axis perpendicular to a plane of a surface of the antenna that emits radiation, the beam control element comprising;

at least partially reflective material; and

an absorptive material positioned between the antenna and the at least partially reflective material configured to attenuate signals emitted or received by the antenna at a second azimuth angle that is greater than the first azimuth angle relative to at least one signal emitted or received by the antenna at a third azimuth angle less than the first angle.

2. The apparatus according to claim 1, wherein the beam control element is positioned to reflect side lobe radiation in the direction of main lobe radiation.

3. The apparatus according to claim 1, wherein the beam control element is configured to reflect side lobe radiation emitted by the antenna at the second azimuth angle in the direction of main lobe radiation emitted from the antenna at the third azimuth angle.

4. The apparatus according to claim 1, wherein the beam control element is configured to reduce a gain of the antenna in a direction of at an azimuth angles that are greater than the first azimuth angle.

5. The apparatus according to claim 4, wherein the beam control element is configured to substantially block signals approaching the antenna at the second azimuth angle.

6. The apparatus according to claim 1, wherein the at least one antenna is configured to emit and receive radar signals.

7. The apparatus according to claim 1, wherein the at least one antenna is one of a plurality of antennas configured in an array.

8. The apparatus according to claim 7, wherein the array is an electronically scanning array.

9. The apparatus according to claim 1, wherein signals emitted by the antenna in a direction at less than the first azimuth angle are not attenuated by the beam control element.

10. The apparatus according to claim 7, wherein the beam control element is positioned proximate the array at a first planar angle relative to a surface of the array that emits radiation and configured to attenuate signals approaching the array at an angle that is less than the first planar angle and enhance at least one signal emitted from the array at an angle greater than the first angle.

11. The apparatus according to claim 1, wherein the beam control element is positioned between the at least one antenna and another antenna.

12. The apparatus according to claim 1, wherein the beam control element is not electrically coupled to the antenna:

14. The apparatus according to claim 1, wherein the antenna is configured to receive and emit communication signals.

13. (canceled)

15. A method of controlling radiation reflected from a structure toward an antenna comprising:

providing a first antenna, the antenna being a phased array where the antenna is configured to steer the radiation both azimuthally and by elevation;

providing a beam control element comprising at least partially reflective material and an absorptive material; and

,

positioning the beam control element along a first azimuth angle between a reference azimuth vector perpendicular to a surface of the antenna that emits radiation and a second azimuth angle that defines a direction from the first antenna to the structure, wherein the absorptive material is positioned between the antenna and the at least partially reflective material, thereby attenuating radiation approaching the antenna at the second azimuth angle angle relative to radiation approaching the antenna at an angle less than the first azimuth angle.

16. An apparatus comprising:

a plurality of antennas configured in a phased array to emit and/or receive signals, the plurality of antennas is configured to steer the radiation both azimuthally and by elevation; and

at least one beam control element positioned between at least two of the plurality of antennas at a first azimuth angle relative to an azimuth reference vector perpendicular to a plane of a surface of one of the plurality of antennas, the beam control element comprising partially reflective material and an absorptive material positioned between the at least two of the plurality of antennas, wherein the at least partially reflective material is configured to attenuate signals emitted or received by the plurality of antennas at an angle that is greater than the first azimuth angle and enhance at least one signal emitted or received from the plurality of antennas at an angle less than the first azimuth angle.

17. An apparatus comprising:

a plurality of antennas configured in a phased array, the plurality of antennas is configured to steer the radiation both azimuthally and by elevation; and

at least one beam control element positioned along a perimeter of an antenna of the plurality at a first azimuth angle relative to an azimuth reference vector perpendicular to a plane of a surface of the antenna, the beam control element comprising at least partially reflective material and an absorptive material positioned between the antenna and the at least partially reflective material configured to attenuate signals emitted or received by the antenna at an angle that is greater than the first azimuth angle and enhance at least one signal emitted from the antenna at an angle less than the first azimuth angle.

18. The apparatus according to claim 17, wherein at least two of the plurality of antennas are configured in an array to at least one of emit and receive signals in different directions.

19. The apparatus according to claim 17, wherein at least two of the plurality of antennas are configured in an array to at least one of emit and receive signals in parallel directions.

20. The apparatus according to one of claim 17, wherein the beam control element is further configured to allow overlapping coverage areas between two adjacent antennas.

21. The apparatus according to claim 17, wherein the beam control element is further configured to prevent overlapping coverage areas between two adjacent antennas.

22. An apparatus comprising:

an antenna configured to at least one or emit and receive radiation, the antenna being a phased array where the antenna is configured to steer the radiation both azimuthally and by elevation; and

a beam control element positioned along the perimeter of the antenna at a first azimuth angle relative to an azimuth reference vector perpendicular to a plane of a surface of the antenna that emits radiation, the beam control element comprising;

at least partially reflective material; and

an absorptive material positioned between the antenna and the at least partially reflective material configured to attenuate radiation emitted or received by the antenna at an angle that is greater than the first azimuth angle without substantially diminishing radiation emitted or received by the antenna at an angle less than the first azimuth angle.

23. The apparatus according to claim 22, wherein the radiation emitted from the antenna at an angle less than the first azimuth angle includes a main lobe having a shape, magnitude, and overall power, wherein the beam control element is configured to modify the shape without substantially attenuating the overall power of the main lobe.

24. The apparatus according to claim 22, wherein the radiation emitted from the antenna at an angle less than the first azimuth angle includes a main lobe having a shape, magnitude, and overall power, wherein the beam control element is configured to modify the shape and increase the magnitude of the main lobe.

25. The apparatus according to claim 22, wherein the radiation emitted from the antenna at an angle less than the first azimuth angle includes a main lobe having a shape, magnitude, and overall power and radiation emitted from the antenna at an angle greater than the first azimuth angle includes at least one side lobe, wherein the beam control element is configured to attenuate the at least one side lobe.

26. The apparatus according to claim 25, the beam control element is configured to attenuate the at least one side lobe at angles greater than the first azimuth angle and reflect at least a portion of the power from the side lobe into the main lobe.

27. A system comprising:

a radar field unit configured to be supported by a structure comprising;

an antenna comprising a plurality of antenna elements, wherein the antenna elements are disposed azimuthally around the radar field unit to provide a coverage area in at least a portion of an azimuthal plane, wherein the antenna is a phased array where the radiation from the antenna may be steered both azimuthally and by elevation, and,

at least one a beam control element positioned along a perimeter of the antenna at a first azimuth angle relative to an azimuth reference axis perpendicular to a surface of the antenna that emits radiation, the beam control element comprising;

at least partially reflective material; and

an absorptive material positioned between the antenna and the at least partially reflective material configured to attenuate radiation approaching the antenna from the structure and radiation emitted by the antenna toward the structure.

28. The system according to claim 27, wherein the structure is one of a wind turbine and a communications tower.

29. The system according to claim 27, wherein the the radar field unit is configured to be in close proximity to the structure to detect targets that are approaching the tower using the azimuthal coverage area.

36. The system of claim 27, wherein the antenna excludes any antenna elements that would emit radiation in the direction of the structure.

37. The system of claim 27, wherein the beam control element is planar.

38. The system of claim 27, wherein the radar field unit is an electronically scanning radar system, the antenna elements being phase controlled antenna elements configured for beam steering.

39. The system of claim 27, wherein the beam control element is attached to the field unit and extends in a direction away from field unit.

40. The system of claim 27, wherein the at least partially reflective material is aluminum.

41. The system of claim 27, wherein the absorptive material is a radio frequency absorber material.

30-35. -35. (canceled)