Fast beam patterns

• US 10,601,130 B2
• Filed: 07/20/2017
• Issued: 03/24/2020
• Est. Priority Date: 07/21/2016
• Status: Active Grant

• Current Assignee: Echodyne Corp.
• Original Assignee: Echodyne Corp.
• Inventors: Driscoll, Tom, Graves, Jr., William F., Hunt, John Desmond, Landy, Nathan Ingle, Lambrecht, Christopher L., Perque, Milton, Worl, Robert Tilman
• Primary Examiner(s): Phan, Dao L
• Application Number:
  US15/655,505
• Publication Number:
  US 20180026365A1
• Time in Patent Office: 978 Days
• Field of Search: 342379
• CPC Class Codes: G01S 13/4463 using phased arrays
• CPC Class Codes: G01S 7/2813 Means providing a modification of the radiation pattern for cancelling noise, clutter or interfering signals, e.g. side lobe suppression, side lobe blanking, null-steering arrays specially adapted to secondary radar systems G01S13/762; aerials or aerials systems H01Q21/29, H01Q25/00
• CPC Class Codes: H01Q 21/005 Slotted waveguides arrays
• CPC Class Codes: H01Q 21/065 Patch antenna array
• 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 3/24 varying the orientation by switching energy from one active radiating element to another, e.g. for beam switching
• CPC Class Codes: H01Q 3/26 varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture H01Q3/12, H01Q3/22, H01Q3/24 take precedence
• CPC Class Codes: H01Q 9/0442 with particular tuning means

Abstract

An embodiment of an antenna comprises an array of antenna elements arranged in groups of antenna elements adjustably coupled to respective reference waves. A multiplicity of patterns of antenna coupling settings are defined, each of which gives rise to a main lobe which points the antenna in a particular direction, each pattern also giving rise to respective side lobes. First and second such patterns may point the antenna in the same direction but with non-identical side lobes. In this way the clutter level from the side lobes relative to the main lobe is much smaller than would be the case if one of the patterns were employed both for transmitting and receiving. Alternatively, the first and second patterns may be used in quick succession both for transmitting, or used in quick succession both for receiving. The antenna may also switch rapidly between patterns where the main lobe points in a different direction in each pattern, allowing dithering of the beam or rapid switching between scanning and tracking.

Claims

1. An antenna system, comprising:

an antenna having antenna elements; and

a control circuit configured

to activate a first group of the antenna elements during a first time to cause the antenna to generate a first beam pattern including a first main lobe having a main-lobe direction and having a main-lobe beam width and including a first side lobe having a first side-lobe direction, and

to activate a second group of the antenna elements during a second time to cause the antenna to generate a second beam pattern that is different from the first beam pattern, the second beam pattern including a second main lobe having approximately the main-lobe direction and having approximately the main-lobe beam width and including a second side lobe having a second side-lobe direction that is different from the first side-lobe direction.

2. The antenna system of claim 1 wherein:

the first main lobe emanates from a main-lobe location of the antenna;

the second main lobe approximately emanates from the main-lobe location;

the first side lobe emanates from a first side-lobe location of the antenna; and

the second side lobe approximately emanates from the first side-lobe location.

3. The antenna system of claim 2 wherein the control circuit is further configured:

to activate the first group of antenna elements during the first time to cause the antenna to generate the first beam pattern including a third side lobe having a third side-lobe direction and emanating from a second side-lobe location of the antenna; and

to activate the second group of antenna elements during the second time to cause the antenna to generate the second beam pattern including a fourth side lobe having a fourth side-lobe direction that is different from the third side-lobe direction and approximately emanating from the second side-lobe location.

4. The antenna system of claim 1 wherein the second side-lobe direction is approximately orthogonal to the first side-lobe direction.

5. The antenna system of claim 1, wherein the control circuit is further configured:

to deactivate the first group of the antenna elements before activating the second group of antenna elements; and

to activate the second group of the antenna elements such that the antenna generates the second beam pattern within 250 nanoseconds of the control circuit deactivating the first group of antenna elements.

6. The antenna system of claim 1 wherein:

the control circuit is configured to generate a reference signal having a wavelength and to couple the reference signal to the antenna; and

each antenna element is spaced apart from a closest other antenna element by a distance that is less than half of the wavelength.

7. The antenna system of claim 1 wherein the control circuit is configured:

to couple a reference signal to the antenna during one of the first time and the second time; and

to receive a signal from the antenna during the other of the first time and the second time.

8. The antenna system of claim 1 wherein the control circuit is configured to couple a reference signal to the antenna during the first time and during the second time.

9. The antenna system of claim 1 wherein the control circuit is configured to receive a signal from the antenna during the first time and during the second time.

10. The antenna system of claim 1 wherein:

the antenna includes a transmission medium having a conductor with gaps respectively adjacent to the antenna elements; and

the control circuit is configure

to generate a reference signal,

to couple the reference signal to the transmission medium, to activate the first group of the antenna elements by reducing a respective

impedance between each antenna element in the first group and a respective one of the gaps; and

to activate the second group of the antenna elements by reducing a respective impedance between each antenna element in the second group and a respective one of the gaps.

11. A method, comprising:

activating a first group of antenna elements of an antenna to generate a first beam pattern including a first main lobe having a main-lobe direction and having a main-lobe beam width and including a first side lobe having a first side-lobe direction; and

activating a second group of antenna elements of the antenna to generate a second beam pattern that is different from the first beam pattern, the second beam pattern including a second main lobe having approximately the main-lobe direction and having approximately the main-lobe beam width and including a second side lobe having a second side-lobe direction that is different from the first side-lobe direction.

12. The method of claim 11 wherein:

the first main lobe emanates from a main-lobe location of the antenna;

the second main lobe emanates from approximately the main-lobe location;

the first side lobe emanates from a first side-lobe location of the antenna; and

the second side lobe emanates from approximately the first side-lobe location.

13. The method of claim 11 wherein:

the first main lobe emanates from a location of the antenna;

the second main lobe emanates from approximately the location;

the first side lobe emanates from approximately the location; and

the second side lobe emanates from approximately the location.

14. The method of claim 11 wherein:

activating the first group of antenna elements includes activating the first group of antenna elements of the antenna to generate the first beam pattern including a third side lobe having a third side-lobe direction and emanating from a second side-lobe location of the antenna; and

activating the second group of antenna elements includes activating the second group of antenna elements of the antenna to generate the second beam pattern including a fourth side lobe having a fourth side-lobe direction that is different from the third side-lobe direction and emanating from approximately the second side-lobe location.

15. The method of claim 11 wherein the second side-lobe direction is approximately perpendicular to the first side-lobe direction.

16. The method of claim 11, further comprising:

deactivating antenna elements that are members of the first group but not members of the second group before activating the second group of antenna elements; and

generating the second beam pattern with the second group of antenna elements within 250 nanoseconds of deactivating the antenna elements that are members of the first group but are not members of the second group.

17. The method of claim 11, further comprising:

generating a reference wave;

wherein activating the first group of antenna elements includes simultaneously coupling the reference wave to each of the antenna elements in the first group; and

wherein activating the second group of antenna elements includes simultaneously coupling the reference wave to each of the antenna elements in the second group.

18. The method of claim 11 wherein:

wherein activating the first group of antenna elements includes simultaneously coupling each of the antenna elements in the first group to a transmission medium; and

wherein activating the second group of antenna elements includes simultaneously coupling each of the antenna elements in the second group to the transmission medium.

19. The method of claim 11, further comprising:

generating a reference wave;

wherein activating the first group of antenna elements includes simultaneously coupling the reference wave to each of the antenna elements in the first group; and

wherein activating the second group of antenna elements includes simultaneously coupling each of the antenna elements in the second group to a transmission medium while a wave from a source remote from the antenna is incident on the antenna elements of the second group.

20. The method of claim 11, further comprising:

generating a reference wave;

wherein activating the first group of antenna elements includes simultaneously coupling each of the antenna elements in the first group to a transmission medium while a wave from a source remote from the antenna is incident on the antenna elements of the first group; and

wherein activating the second group of antenna elements includes simultaneously coupling the reference wave to each of the antenna elements in the second group.

21. The method of claim 11 wherein:

activating the first group of antenna elements includes coupling each of the antenna elements of the first group to a respective gap in a conductor of a transmission medium; and

activating the second group of antenna elements includes coupling each of the antenna elements of the second group to a respective gap in the conductor.

23. The method of claim 11 wherein the second group of antenna elements is different from the first group of antenna elements.

22. A tangible, non-transitory computer-readable medium storing instructions, that when executed by at least one computing circuit, cause the at least one computing circuit, or at least one other circuit under control of the at least one computing circuit:

to activate a first group of antenna elements of an antenna to generate a first beam pattern including a first main lobe having a main-lobe direction and having a main-lobe beam width and including a first side lobe having a first side-lobe direction; and

to activate a second group of antenna elements of the antenna to generate a second beam pattern that is different from the first beam pattern, the second beam pattern including a second main lobe having approximately the main-lobe direction and having approximately the main-lobe beam width and including a second side lobe having a second side-lobe direction that is different from the first side-lobe direction.

24. The tangible, non-transitory computer-readable medium of claim 22 wherein the second group of antenna elements is different from the first group of antenna elements.