Ortho-Mode Transducer With Opposing Branch Waveguides

Abstract

There is disclosed an ortho-mode transducer fabricated as a single piece. The ortho-mode transducer may include a first surface having an aperture defining a common port, a second surface having an aperture defining a vertical port, and a third surface having an aperture defining a horizontal port. The second and third surfaces may be essentially parallel and normal to the first surface. A common waveguide may coupled to the common port, the common waveguide supporting orthogonal vertical and horizontal modes. A vertical branching waveguide may couple the vertical mode between the vertical port and the common waveguide while rejecting the horizontal mode. A horizontal branching waveguide may couple the horizontal mode between the horizontal port and the common waveguide while rejecting the vertical mode.

Description

DESCRIPTION OF THE DRAWINGS

FIG. 1A and FIG. 1B are perspective drawings of a prior art OMT.

FIG. 2 is a perspective drawing of an exemplary OMT with opposing branch waveguides.

FIG. 3A is a front view of the ortho-mode transducer of FIG. 2.

FIG. 3B is a side view of the ortho-mode transducer of FIG. 2.

FIG. 3C is a top view of the ortho-mode transducer of FIG. 2.

FIG. 3D is a bottom view of the ortho-mode transducer of FIG. 2.

FIG. 4A is a cross-sectional view of cut-plane 4a in FIG. 3B.

FIG. 4B is a cross-sectional view of cut-plane 4b in FIG. 3B.

FIG. 4C is a cross-sectional view of cut-plane 4c in FIG. 3C.

FIG. 4D is a cross-sectional view of cut-plane 4d in FIG. 3B.

FIG. 5 is a cross-sectional view illustrating a machining operation.

FIG. 6A-6C are cross-sectional views illustrating a series of machining operations.

FIG. 7A-7D are cross-sectional views illustrating a series of machining operations.

Claims

1. An ortho-mode transducer, comprising: a first surface having a common port aperturea second surface a vertical port aperture, the second surface essentially normal to the first surfacea third surface having a horizontal port aperture, the third surface essentially normal to the first surface and essentially parallel to the second surfacea common waveguide coupled to the common port aperture, the common waveguide supporting orthogonal vertical and horizontal modesa vertical branching waveguide to couple the vertical mode between the vertical port aperture and the common waveguide while rejecting the horizontal modea horizontal branching waveguide to couple the horizontal mode between the horizontal port aperture and the common waveguide while rejecting the vertical modewherein the ortho-mode transducer is fabricated from a single piece.

2. The ortho-mode transducer of claim 1, wherein the common waveguide, the vertical branching waveguide, and the horizontal branching waveguide are all symmetrical about a common symmetry plane.

3. The ortho-mode transducer of claim 2, wherein an axis of the vertical branching waveguide and an axis of the horizontal branching waveguide are parallel.

4. The ortho-mode transducer of claim 1, wherein the single piece is a metal material.

5. The ortho-mode transducer of claim 1, wherein the single piece is a dielectric material.

6. The ortho-mode transducer of claim 1, wherein the horizontal branching waveguide comprises a plurality of horizontal branching waveguide sections, each horizontal branching waveguide section having a cross-sectional shape different from each other of the plurality of horizontal branching waveguide sections.

7. The ortho-mode transducer of claim 6, wherein the horizontal branching waveguide section having the largest cross-sectional shape is adjacent to the horizontal port apertureeach successive horizontal branching waveguide section having a cross-sectional shape smaller than and contained within the cross-sectional shape of the preceding horizontal branching waveguide section.

8. The ortho-mode transducer of claim 1, wherein the vertical branching waveguide comprises a plurality of vertical branching waveguide sections, each vertical branching waveguide section having a cross-sectional shape different from each other of the plurality of vertical branching waveguide sections.

9. The ortho-mode transducer of claim 8, wherein the vertical branching waveguide section having the largest cross-sectional shape is adjacent to the vertical port apertureeach successive vertical branching waveguide section having a cross-sectional shape smaller than and contained within the cross-sectional shape of the preceding vertical branching waveguide section.

10. The ortho-mode transducer of claim 1, wherein the common waveguide comprises a plurality of common waveguide sections, each common waveguide section having a cross-sectional shape different from each other of the plurality of common waveguide sections.

11. The ortho-mode transducer of claim 10, wherein the common waveguide section having the largest cross-sectional shape is adjacent to the common port apertureeach successive common waveguide section having a cross-sectional shape smaller than and contained within the cross-sectional shape of the preceding common waveguide section.

12. The ortho-mode transducer of claim 1, wherein the first surface comprises a first flange.

13. The ortho-mode transducer of claim 1, wherein the second surface comprises a second flange.

14. The ortho-mode transducer of claim 1, wherein the third surface comprises a third flange.

15. A method of fabricating an ortho-mode transducer including a common waveguide divided into one or more common waveguide sections, a vertical branching waveguide divided into a plurality of vertical branching waveguide sections and a horizontal branching waveguide divided into a plurality of horizontal branching waveguide sections, the method comprising forming the common waveguide by a first set of machining operations, where the number of operations in the first set is equal to the number of common waveguide sectionsforming the vertical branching waveguide by a second set of machining operations, where the number of operations in the second set is equal to the number of vertical branching waveguide sectionsforming the horizontal branching waveguide by a third set of machining operations, where the number of operations in the third set is equal to the number of horizontal branching waveguide sections.

16. The method of fabricating an ortho-mode transducer of claim 15, further comprising forming a blank approximating the shape of the ortho-mode transducer prior to machining operations.

17. An ortho-mode transducer produced by the method of claim 15.

18. An ortho-mode transducer, comprising: a first surface having an aperture defining a common porta second surface having an aperture defining a vertical port, the second surface essentially normal to the first surfacea third surface having an aperture defining a horizontal port, the third surface essentially normal to the first surface and essentially parallel to the second surfacea common waveguide coupled to the common port, the common waveguide supporting orthogonal vertical and horizontal modesa vertical branching waveguide to couple the vertical mode between the vertical port and the common waveguide while rejecting the horizontal mode, the vertical branching waveguide further comprising a first vertical branching waveguide section coupled to the vertical porta second vertical branching waveguide section between the first vertical branching waveguide section and the common waveguide, the second vertical branching waveguide section having a cross-section that is smaller than and contained within a cross section of the first vertical branching waveguide sectiona horizontal branching waveguide to couple the horizontal mode between the horizontal port and the common waveguide while rejecting the vertical mode, the horizontal branching waveguide further comprising a first horizontal branching waveguide section coupled to the horizontal porta second horizontal branching waveguide section between the first horizontal branching waveguide section and the common waveguide, the second horizontal branching waveguide section having a cross-section that is smaller than and contained within a cross section of the first horizontal branching waveguide section.

19. The ortho-mode transducer of claim 18, wherein the common waveguide, the vertical branching waveguide, and the horizontal branching waveguide are all symmetrical about a common symmetry plane.

20. The ortho-mode transducer of claim 19, wherein an axis of the vertical branching waveguide and an axis of the horizontal branching waveguide are parallel.