Multi-beam antenna

• US 6,606,077 B2
• Filed: 07/23/2002
• Issued: 08/12/2003
• Est. Priority Date: 11/18/1999
• Status: Active Grant

• Current Assignee: Joyson Safety Systems Acquisition, LLC
• Original Assignee: Automotive Systems Laboratory, Incorporated (Ningbo Junsheng Investment Group Co., Ltd.)
• Inventors: Ebling, James P., Rebeiz, Gabriel
• Primary Examiner(s): LE, HOANGANH T
• Application Number:
  US10/202,242
• Publication Number:
  US 20030006941A1
• Time in Patent Office: 385 Days
• Field of Search: H01/Q 1.502, H01/Q 1.508, 343/909, 343/911.L, 343/754, 343/753, 343/911.R, 343/853, 343/755
• US Class Current: 343/911.00L
• CPC Class Codes: H01Q 15/04 comprising wave-guiding channel or channels bounded by effective conductive surfaces substantially perpendicular to the electric vector of the wave, e.g. parallel-plate waveguide lens
• CPC Class Codes: H01Q 15/08 formed of solid dielectric material
• CPC Class Codes: H01Q 19/062 for focusing
• CPC Class Codes: H01Q 19/195 wherein a reflecting surface acts also as a polarisation filter or a polarising device
• CPC Class Codes: H01Q 21/0031 Parallel-plate fed arrays; Lens-fed arrays multibeam arrays H01Q25/008
• 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 25/008 lens fed multibeam arrays
• CPC Class Codes: H01Q 3/242 Circumferential scanning
• CPC Class Codes: H01Q 3/245 in the focal plane of a focussing device

Abstract

A multi-beam antenna comprises an electromagnetic lens, at least one first antenna feed element, at least one second antenna feed element, and a selective element located between first and second portions of the electromagnetic lens with which the respective antenna feed elements respectively cooperate. The transmissivity and reflectivity of the selective element are responsive to an electromagnetic wave property, e.g. frequency or polarization. A first electromagnetic wave in cooperation with the at least one first antenna feed element and having a first value of the electromagnetic wave property is substantially transmitted through the selective element so as to propagate in both the first and second portions of the electromagnetic lens. A second electromagnetic wave in cooperation with the at least one second antenna feed element and having a second value of the electromagnetic wave property is substantially reflected by the selective element.

Claims

1. A multi-beam antenna, comprising:

a. an electromagnetic lens, wherein said electromagnetic lens comprises a first portion and a second portion;

b. at least one first antenna feed element, wherein said at least one first antenna feed element is adapted to cooperate with said first portion of said electromagnetic lens;

c. at least one second antenna feed element, wherein said at least one second antenna feed element is adapted to cooperate with said second portion of said electromagnetic lens; and

d. a selective element located between said first and second portions of said electromagnetic lens, wherein said selective element has a transmissivity and a reflectivity, said transmissivity and said reflectivity are responsive to an electromagnetic wave property, the transmissivity of said selective element is adapted so that a first electromagnetic wave having a first value of said electromagnetic wave property is substantially transmitted through said selective element so as to propagate in both said first and second portions of said electromagnetic lens, the reflectivity of said selective element is adapted so that a second electromagnetic wave having a second value of said electromagnetic wave property is substantially reflected by said selective element, said first electromagnetic wave cooperates with said at least one first antenna feed element, and said second electromagnetic wave cooperates with said at least one second antenna feed element.

2. A multi-beam antenna as recited in claim 1, wherein said electromagnetic lens is selected from a spherical lens, a Luneburg lens, a spherical shell lens, a hemispherical lens, an at least partially spherical lens, an at least partially spherical shell lens, a cylindrical lens, and a rotational lens.

3. A multi-beam antenna as recited in claim 1, wherein said at least one first antenna feed element has a corresponding at least one first axis of principal gain, said at least one first axis of principal gain is directed through both said first and second portions of said electromagnetic lens, said at least one second antenna feed element has a corresponding at least one second axis of principal gain, said at least one second axis of principal gain is directed through at least said second portion of said electromagnetic lens, and said at least one second antenna feed element and said selective element are adapted so that a reflection of at least one of said at least one second axis of principal gain from said selective element is generally aligned with at least one said at least one first axis of principal gain in said second portion of said electromagnetic lens.

4. A multi-beam antenna as recited in claim 1, wherein said at least one first antenna feed element has a corresponding first median axis of principal gain, said first median axis of principal gain is directed through both said first and second portions of said electromagnetic lens, said at least one second antenna feed element has a corresponding second median axis of principal gain, said second median axis of principal gain is directed through at least said second portion of said electromagnetic lens, and said at least one second antenna feed element and said selective element are adapted so that a reflection of said second median axis of principal gain from said selective element is generally aligned with said first median axis of principal gain in said second portion of said electromagnetic lens.

5. A multi-beam antenna as recited in claim 1, wherein at least one first antenna feed element comprises a first end-fire antenna element adapted to launch electromagnetic waves in a direction substantially towards said first portion of said at least one electromagnetic lens, said direction for at least one said first end-fire antenna element is different for said direction of at least another said first end-fire antenna element, at least one second antenna feed element comprises a second end-fire antenna element adapted to launch electromagnetic waves in a direction substantially towards said second portion of said at least one electromagnetic lens, and said direction for at least one said second end-fire antenna element is different for said direction of at least another said second end-fire antenna element.

6. A multi-beam antenna as recited in claim 5, wherein said first and second end-fire antenna elements are selected from a Yagi-Uda antenna, a coplanar horn antenna, a Vivaldi antenna, a tapered dielectric rod, a slot antenna, a dipole antenna, and a helical antenna.

7. A multi-beam antenna as recited in claim 1, wherein said at least one first antenna feed element comprises a plurality of first antenna feed elements arranged substantially on a first plane, and said at least one second antenna feed element comprises a plurality of first antenna feed elements arranged substantially on a second plane.

8. A multi-beam antenna as recited in claim 7, wherein said first and second planes are at least substantially parallel to one another.

9. A multi-beam antenna as recited in claim 8, wherein said first and second planes are at least substantially coplanar.

10. A multi-beam antenna as recited in claim 1, wherein said selective element is substantially located on a third plane.

11. A multi-beam antenna as recited in claim 7, wherein said first plane, said second plane, and said selective element are each substantially perpendicular to a fourth plane.

12. A multi-beam antenna as recited in claim 1, wherein said electromagnetic wave property comprises frequency.

13. A multi-beam antenna as recited in claim 12, wherein said first electromagnetic wave comprises a first carrier frequency, said second electromagnetic wave comprises a second carrier frequency, and said second carrier frequency is different from said first carrier frequency.

14. A multi-beam antenna as recited in claim 12, wherein said selective element comprises a plurality of kernel elements, each said kernel element comprising either a conductor or an aperture in a conductor, each said kernel element having a shape selected from a Jerusalem Cross, a circular shape, a doughnut shape, a rectangular shape, a square shape, and a potent cross shape.

15. A multi-beam antenna as recited in claim 12, wherein said selective element comprises a plurality of at least partially conductive layers that are adapted to control harmonic modes.

16. A multi-beam antenna as recited in claim 12, wherein said selective element comprises a periodic structure of conductive elements.

17. A multi-beam antenna as recited in claim 16, wherein said periodic structure of conductive elements are located on a dielectric substrate.

18. A multi-beam antenna as recited in claim 16, wherein said conductive elements have a shape selected from a Jerusalem Cross, a circular shape, a doughnut shape, a rectangular shape, a square shape, and a potent cross shape.

19. A multi-beam antenna as recited in claim 1, wherein said electromagnetic wave property comprises polarization.

20. A multi-beam antenna as recited in claim 19, wherein said selective element comprises a polarized reflector.

21. A multi-beam antenna as recited in claim 20, wherein said at least one first antenna feed element is polarized in accordance with a first polarization, said at least one second antenna feed element is polarized in accordance with a second polarization, and said second polarization is orthogonal to said first polarization.

22. A multi-beam antenna as recited in claim 20, further comprising a polarization rotator located either between said at least one first antenna feed element and said selective element or between said at least one second antenna feed element and said selective element.

23. A multi-beam antenna as recited in claim 22, wherein said polarization rotator is located either between said at least one first antenna feed element and said first portion of said electromagnetic lens or said at least one second antenna feed element and said second portion of said electromagnetic lens.

24. A multi-beam antenna as recited in claim 22, wherein said polarization rotator is incorporated in either said first portion of said electromagnetic lens or said second portion of said electromagnetic lens.

25. A method of transmitting or receiving electromagnetic waves, comprising:

a. transmitting or receiving a first electromagnetic wave along a first direction through an first portion of an electromagnetic lens;

b. transmitting or receiving a second electromagnetic wave through a second portion of said electromagnetic lens; and

c. reflecting a substantial portion of said second electromagnetic wave from a selective element in a region between said first and second portions of said electromagnetic lens, wherein the operations of transmitting or receiving a second electromagnetic wave through a second portion of said electromagnetic lens and reflecting said second electromagnetic wave from said selective element in said region between said first and second portions of said electromagnetic lens are adapted so that both said first and second electromagnetic waves propagate along a similar median direction within said second portion of said electromagnetic lens.

26. A method of transmitting or receiving electromagnetic waves as recited in claim 25, wherein a carrier frequency of said first electromagnetic wave is different from a carrier frequency of said second electromagnetic wave, and the operation of reflecting said second electromagnetic wave is responsive to a carrier frequency of said second electromagnetic wave.

27. A method of transmitting or receiving electromagnetic waves as recited in claim 25, wherein a polarization of said first electromagnetic wave is different from a polarization of said second electromagnetic wave, and the operation of reflecting said second electromagnetic wave is responsive to a polarization of said second electromagnetic wave.