Millimeter-wave signal transmission device

• US 6,952,143 B2
• Filed: 07/25/2003
• Issued: 10/04/2005
• Est. Priority Date: 07/25/2003
• Status: Expired due to Fees

• Current Assignee: Autoliv ASP Incorporated (Autoliv Incorporated)
• Original Assignee: M/A Com
• Inventors: Cushman, John F., Douglas, Allan S., Kinayman, Noyan
• Primary Examiner(s): WAMSLEY, PATRICK G
• Application Number:
  US10/628,635
• Publication Number:
  US 20050017818A1
• Time in Patent Office: 802 Days
• Field of Search: 333/26, 333/21.R, 333/22.R, 333/24.1, 333/33, 333/202, 330/66, 343/771, 385/94
• US Class Current: 333/26
• CPC Class Codes: H01P 5/107 Hollow-waveguide/strip-line transitions

Abstract

A transition for transmitting a mm-wave signal from one plane to another, the transition comprising: (a) first and second transmission lines on parallel planes; (b) a third transmission line orthogonal to the first and second transmission lines, wherein either the first and second transmission lines are suitable for transmitting a TEM mode signal and the third transmission line is suitable for transmitting a waveguide mode signal, or the third transmission line is suitable for transmitting a TEM mode signal and the first and second transmission lines are suitable for transmitting a waveguide mode signal; and (c) first and second transducers, the first transducer coupled between the first and third transmission lines, the second transducer coupled between the second and third transmission lines, each of the transducers suitable for converting a TEM mode signal to a waveguide mode signal.

Claims

1. A transition for transmitting a mm-wave signal from one plane to another, said transition comprising:

first and second transmission lines on parallel planes;

a waveguide orthogonal to said first and second transmission lines, wherein said first and second transmission lines are suitable for transmitting a TEM mode signal and said waveguide is suitable for transmitting a waveguide mode signal;

a support plate between said first and second transmission lines, said support plate defining a borehole with conductive walls between said first and second transmission lines;

a metalized dielectric filler comprising at least one conductive layer and being disposed in said borehole such that said conductive layer and at least a portion of said conductive walls of said borehole form said waveguide, whereby said waveguide is smaller than said borehole.

2. The transition of claim 1, further comprising first and second transducers, said first transducer coupled between said first transmission line and said waveguide, said second transducer coupled between said second transmission line and said waveguide, each of said transducers having a conversion portion comprising one or more fins perpendicular to its respective transmission line and being suitable for converting a signal between a TEM mode and a rectangular waveguide mode having a waveguide portion adjacent said waveguide to facilitate coupling of a signal in said rectangular waveguide mode between said waveguide and the transducer.

3. The transition of claim 2, wherein each transducer comprises:

a transmission portion connected to its respective transmission line; and

said waveguide portion being configured to facilitate the propagation of a waveguide mode signal therethrough in a plane orthogonal to the transmission portion.

4. The transition of claim 3, wherein said transmission portion, said waveguide portion, and said conversion portion share a common substrate.

5. The transition of claim 4, wherein said waveguide portion comprises a conductive barrier defined in said substrate.

6. The transition of claim 5, wherein said conductive barrier is a metallic wall.

7. The transition of claim 5, wherein said conductive barrier is a perforated metallic wall.

8. The transition of claim 3, wherein said metalized dielectric filler has an impendence which matches that of said waveguide portion.

9. The transition of claim 2, wherein said first and second transmission lines and said first and second transducers are disposed on first and second mm-wave boards;

respectively.

10. The transition of claim 9, wherein said mm-wave boards are overlapping.

11. The transition of claim 10, wherein said mm-wave boards are separated by a distance of at least 10% of an operating signal wavelength.

12. The transition of claim 9, wherein at least one of said mm-wave boards comprises electrical circuitry.

13. The transition of claim 2, wherein said first transducer converts a TEM mode signal to a rectangular waveguide mode signal and said second transducer converts a rectangular waveguide mode-signal to a TEM mode signal.

14. The transition of claim 13, wherein said rectangular waveguide mode signal is a TE₁₀ mode signal.

15. The transition of claim 2, wherein said first and second transducers are identical.

16. The transition of claim 1, wherein said first or second transmission line is a microstrip.

17. The transition of claim 1, wherein said waveguide is a rectangular waveguide.

18. The transition of claim 1, wherein said waveguide has a length of at least 0.25 mm.

19. The transition of claim 1, wherein said support plate is rigid.

20. The transition of claim 1, wherein said support plate is metal.

21. The transition of claim 1, wherein said support plate is at least 1mm thick.

22. An ACC system comprising the transition of claim 1.

23. A method for transmitting a mm-wave signal from a first plane to a second plane using a transition, method comprising:

providing a transition for transmitting a mm-wave signal from one plane to another, said transition comprising;

first and second transmission lines on parallel planes;

waveguide orthogonal to said first and second transmission lines, wherein said first and second transmission lines are suitable for transmitting a TEM mode signal and said waveguide is suitable for transmitting a waveguide mode signal;

a support plate between said first and second transmission lines, said support plate defining a borehole with conductive walls between said first and second transmission lines;

a metalized dielectric filler comprising at least one conductive layer and being disposed in said borehole such that said conductive layer and at least a portion of said conductive walls of said borehole form said waveguide, whereby said waveguide is smaller than said borehole;

transmitting a mm-wave signal along said first transmission line;

converting said signal from a TEM mode a waveguide mode using a transducer;

transmitting said signal along said waveguide in said waveguide mode to a second plane parallel to said first plane;

converting said signal back to said TEM mode; and

transmitting said signal in said TEM mode along said second transmission line in said second plane.

24. The method of claim 23, wherein said signal is between about 65 to about 85 GHz.

25. The method of claim 23, wherein the reflective loss is better than 15 dB and the insertion loss is better than 0.6 dB.

26. The method of claim 23, wherein the length of said wave guide is greater than 10% of the wavelength of said signal.