Slot coupled, polarized, egg-crate radiator

• US 6,624,787 B2
• Filed: 10/01/2001
• Issued: 09/23/2003
• Est. Priority Date: 10/01/2001
• Status: Expired due to Term

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Puzella, Angelo M., Beltran, Fernando
• Primary Examiner(s): Clinger, James
• Application Number:
  US09/968,685
• Publication Number:
  US 20030067410A1
• Time in Patent Office: 722 Days
• Field of Search: 343/700.MS, 343/769, 343/778, 343/767, 343/770, 343/787, 343/725, 343/853
• US Class Current: 343/700.0MS
• CPC Class Codes: H01Q 21/0087 Apparatus or processes specially adapted for manufacturing antenna arrays manufacturing waveguides H01P11/00
• CPC Class Codes: H01Q 21/065 Patch antenna array
• CPC Class Codes: H01Q 9/0407 Substantially flat resonant element parallel to ground plane, e.g. patch antenna dipole H01Q9/285; monopole H01Q9/40
• CPC Class Codes: H01Q 9/0414 in a stacked or folded configuration

Abstract

A radiator includes a waveguide having an aperture and a patch antenna disposed in the aperture. In one embodiment, an antenna includes an array of waveguide antenna elements, each element having a cavity, and an array of patch antenna elements including an upper patch element and a lower patch element disposed in the cavity.

Claims

1. A radiator, responsive to radio frequency (RF) signals in a predetermined frequency range, said radiator comprising:

a waveguide defined by sidewalls having dimensions selected such that the waveguide operates in a cut-off mode within the predetermined frequency range; and

a patch antenna disposed in said waveguide, said patch antenna having dimensions such that the combination of said patch antenna and said waveguide operates in a substantially resonant mode within the predetermined frequency range.

2. The radiator of claim 1, wherein said patch antenna is electromagnetically coupled to said waveguide.

3. The radiator of claim 1, further comprising a patch antenna support layer disposed adjacent to said waveguide aperture;

and

wherein said patch antenna is supported by said support layer.

4. The radiator of claim 3, where the patch antenna support layer is a dielectric.

5. The radiator of claim 1, further comprising a feed circuit electromagnetically coupled to said waveguide, wherein electromagnetic signals pass from said feed circuit into said waveguide and said waveguide is disposed between said feed circuit and said patch antenna.

6. The radiator of claim 5, further comprising a slot layer having at least one slot, disposed between said feed circuit and said patch antenna.

7. The radiator of claim 6, wherein said at least one slot is non-resonant.

8. The radiator of claim 6, wherein said at least one slot has a length less than λ

/2, where λ

is a free space wavelength radiated by said radiator.

9. The radiator of claim 6, wherein said feed circuit comprises:

a stripline transmission line layer;

a ground plane layer; and

wherein said stripline transmission line layer is spaced closer to said at least one slot than to said ground plane layer.

10. The radiator of claim 1, wherein said waveguide is aluminum.

11. The radiator of claim 1, wherein said waveguide is an injection molded material coated with a metal layer.

12. The radiator of claim 1, further comprising a plurality of patch antennas wherein at least one of said patch antennas is resonant at a first frequency and at least another one of the patch antennas is resonant at a different second frequency.

13. The radiator of claim 1, further comprising:

a second waveguide, having an second aperture, disposed adjacent said patch antenna; and

a second patch antenna disposed said in the second aperture.

14. The radiator of claim 13, wherein said patch antenna is resonant at a first frequency and said second patch antenna is resonant at a different second frequency.

15. The radiator of claim 1, wherein said patch antenna is copper.

16. The radiator of claim 1, further comprising a plurality of waveguides.

17. A radiator comprising:

a waveguide having an aperture; and

a patch antenna disposed in said aperture, wherein said patch antenna is an optically active material.

18. A radiator comprising:

a waveguide having an aperture; and

a patch antenna disposed in said aperture, said patch antenna further comprising an integrated edge treatment to reduce edge diffraction.

19. A radiator comprising:

a waveguide having an aperture; and

a patch antenna disposed in said aperture wherein said waveguide further comprises a heater disposed on said waveguide.

20. An antenna, adapted for operation in a predetermined frequency range, the antenna comprising:

a plurality of waveguide antenna elements arranged to provide the antenna as an array antenna each of said waveguide antenna elements having a cavity defined by sidewalls having dimensions selected such that each waveguide antenna element in said array of waveguide antenna elements operates in a cut-off mode within the predetermined frequency range; and

a plurality of patch antenna elements, each of said plurality of patch antenna elements comprising an upper patch element and a lower patch element and each of said plurality of patch antenna elements disposed in the cavity of a respective one of said plurality of waveguide antenna elements.

21. The antenna of claim 20 wherein said array of waveguide antenna elements comprises a pair of conductive lattices spaced apart and separated by said lower patch layer.

22. An antenna comprising:

a first dielectric layer comprising a first plurality of antenna elements responsive to radio frequency signals having a first frequency;

a first monolithic conductive lattice disposed adjacent to said first dielectric layer;

a second dielectric layer comprising a second plurality of antenna elements responsive to radio frequency signals having a second different frequency, disposed adjacent to said first monolithic conductive lattice;

a second monolithic conductive lattice disposed adjacent to said second dielectric layer; and

wherein said first lattice and said second lattice form a plurality of waveguides, each waveguide associated with each of a corresponding said first and corresponding second plurality of antenna elements.

23. The antenna of claim 22, further comprising a feed layer having a plurality of feed circuits, disposed adjacent to said first lattice wherein each of said feed circuits communicates an electromagnetic signal to a corresponding waveguide formed in said first lattice.

24. The antenna of claim 23, further comprising a slot layer having at least one slot disposed between said feed layer and said first lattice;

and

wherein said at least one slot communicates an electromagnetic signal to a corresponding waveguide formed in said first lattice.

25. The antenna of claim 24, wherein said at least one slot is non-resonant.

26. The antenna of claim 23, wherein each of the plurality of waveguides isolates the electromagnetic signal provided by each corresponding feed circuit from each of the neighboring waveguides.

27. An antenna adapted for operation in a predetermined frequency range, the antenna comprising:

an array of waveguide antenna elements, each element having a cavity; and

an array of patch antenna elements comprising an upper patch element and a lower patch element disposed in the cavity wherein said array of waveguide antenna elements comprises a pair of conductive lattices spaced apart and separated by said lower patch layer.

28. A method of fabricating an antenna comprising:

providing a plurality of dielectric layers having an upper surface and a lower surface;

forming a plurality of antenna elements on said lower surface of said plurality of dielectric layers;

providing a plurality of monolithic three dimensional conductive lattices; and

bonding each of said plurality of dielectric layers to a corresponding each of said plurality of lattices such that the plurality of patch antenna elements are aligned in a plurality of waveguides formed by said plurality of lattices and the plurality of dielectric layers is interleaved with the plurality of lattices.

29. The method of claim 28, wherein bonding comprises soldering said plurality of dielectric layers to a corresponding each of said plurality of lattices.

30. The method of claim 28, wherein bonding comprises joining said plurality of dielectric layers to a corresponding each of said plurality of lattices with non-lossy bonding adhesives.

31. The method of claim 28, wherein bonding comprises joining said plurality of dielectric layers to a corresponding each of said plurality of lattices with fasteners.

32. The method of claim 28, wherein said dielectric layer has a relative dielectric constant greater than 6 such that a thickness of said dielectric layer is minimized.

33. The method of claim 28, further comprising providing a feed layer and bonding said feed layer to one of said plurality of lattices.

34. The method of claim 28, further comprising scaling the frequency without changing the material composition of the antenna.

35. A radiator, responsive to radio frequency (RF) signals in a predetermined frequency range, said radiator comprising:

a waveguide defined by sidewalls having dimensions selected such that said waveguide is provided having an inductive impedance characteristic within the predetermined frequency range; and

a patch antenna disposed in said waveguide, said patch antenna having dimensions selected such that said patch antenna is provided having a capacitive impedance characteristic selected to substantially cancel the inductive impedance characteristic over the predetermined frequency range.

36. The radiator of claim 35 wherein said patch antenna comprises:

a first patch radiator having dimensions such that said first patch radiator is resonant at a first frequency; and

a second patch radiator disposed over said first patch radiator, said second patch radiator having dimensions such that said second patch radiator is resonant at second different frequency.