Waveguide device, and antenna device including the waveguide device

• US 10,559,890 B2
• Filed: 07/27/2018
• Issued: 02/11/2020
• Est. Priority Date: 01/29/2016
• Status: Active Grant

• Current Assignee: Nidec Corporation, Wgr Co., Ltd.
• Original Assignee: Nidec Corporation
• Inventors: Kirino, Hideki, Kamo, Hiroyuki
• Primary Examiner(s): Phan, Tho G
• Application Number:
  US16/047,060
• Publication Number:
  US 20180375219A1
• Time in Patent Office: 564 Days
• CPC Class Codes: G01S 7/03 Details of HF subsystems specially adapted therefor, e.g. common to transmitter and receiver
• CPC Class Codes: H01P 1/182 Waveguide phase-shifters H01P1/181, H01P1/185, H01P1/19 take precedence
• CPC Class Codes: H01P 3/123 with a complex or stepped cross-section, e.g. ridged or grooved waveguides H01P3/14 takes precedence
• CPC Class Codes: H01P 5/12 Coupling devices having more than two ports H01P5/04 takes precedence
• CPC Class Codes: H01Q 13/06 Waveguide mouths horns H01Q13/02
• CPC Class Codes: H01Q 13/065 provided with a flange or a choke
• CPC Class Codes: H01Q 21/064 using horn or slot aerials slotted waveguides arrays H01Q21/005

Abstract

A waveguide device for use in propagating an electromagnetic wave of a band having a shortest wavelength λm in free space includes: a first electrically conductive member having an electrically conductive surface and a first throughhole; a second electrically conductive member including a plurality of electrically conductive rods each having a leading end opposing the electrically conductive surface, the second electrically conductive member having a second throughhole which overlaps the first throughhole as viewed along an axial direction of the first throughhole; and an electrically-conductive waveguiding wall at least partially surrounding a space between the first throughhole and the second throughhole and being surrounded by the plurality of electrically conductive rods, the waveguiding wall allowing the electromagnetic wave to propagate between the first throughhole and the second throughhole. The height of the waveguiding wall is less than λm/2. The distance between an electrically conductive rod among the plurality of electrically conductive rods that is adjacent to the waveguiding wall and the outer periphery of the waveguiding wall is less than λm/2.

Claims

1. A waveguide device for use in propagating an electromagnetic wave of a band having a shortest wavelength λ

m in free space, the waveguide device comprising;

a first electrically conductive member having an electrically conductive surface and a first throughhole;

a second electrically conductive member including a plurality of electrically conductive rods each having a leading end opposing the electrically conductive surface, the second electrically conductive member having a second throughhole which overlaps the first throughhole as viewed along an axial direction of the first throughhole; and

an electrically-conductive waveguiding wall at least partially surrounding a space between the first throughhole and the second throughhole and being surrounded by the plurality of electrically conductive rods, the waveguiding wall allowing the electromagnetic wave to propagate between the first throughhole and the second throughhole, wherein,

the waveguiding wall has a height which is less than λ

m/2; and

a distance between an electrically conductive rod among the plurality of electrically conductive rods that is adjacent to the waveguiding wall and an outer periphery of the waveguiding wall is less than λ

m/2.

2. The waveguide device of claim 1, wherein at least one of the first electrically conductive member and the second electrically conductive member, and the waveguiding wall, are portions of a single-piece body.

3. The waveguide device of claim 2, wherein,

a gap exists between the waveguiding wall and the first electrically conductive member or the second electrically conductive member;

and

a thickness of the waveguiding wall at a top surface thereof is less than λ

m/2.

4. The waveguide device of claim 3, wherein,

the waveguiding wall and the second electrically conductive member are portions of a single-piece body;

a gap exists between the waveguiding wall and the first electrically conductive member; and

a height of the waveguiding wall is equal to a height of the plurality of electrically conductive rods.

5. The waveguide device of claim 1, wherein the waveguiding wall is split into a first portion that connects to the first electrically conductive member and a second portion that connects to the second electrically conductive member.

6. The waveguide device of claim 5, wherein,

a gap exists between the first portion and the second portion;

a total of a height of the first portion, a height of the second portion, and a length of the gap is less than λ

m/2;

a thickness of the first portion at a top surface thereof is less than λ

m/2; and

a thickness of the second portion at a top surface thereof is less than λ

m/2.

7. The waveguide device of claim 5, wherein a height of the second portion is equal to a height of the plurality of electrically conductive rods.

8. The waveguide device of claim 5, wherein a height of the first portion is greater than that of the second portion.

9. The waveguide device of claim 5, wherein cross sections of the first throughhole, the second throughhole, and the waveguiding wall, as taken along the electrically conductive surface, each include a lateral portion extending in one direction.

10. The waveguide device of claim 9, wherein

the cross sections of the first throughhole, the second throughhole, and the waveguiding wall, as taken along the electrically conductive surface, each further include at least a pair of vertical portions extending in another direction intersecting the one direction, and the lateral portion interconnects the pair of vertical portions;

inner wall surfaces of the first throughhole, the second throughhole, and the waveguiding wall each include at least one projection which projects inward; and

the projection is interposed between the pair of vertical portions, and a leading end of the projection constitutes at least a part of the lateral portion.

11. The waveguide device of claim 9, wherein

the cross sections of the first throughhole, the second throughhole, and the waveguiding wall, as taken along the electrically conductive surface, each further include at least a pair of vertical portions extending in another direction intersecting the one direction, and the lateral portion interconnects the pair of vertical portions;

and

when a central wavelength of the band in free space is λ

o, a thickness of the waveguiding wall at a center of the lateral portion is not less than 0.8 times as large as λ

o/4 and not more than 1.2 times as large as λ

o/4.

12. The waveguide device of claim 9, wherein

inner wall surfaces of the first throughhole, the second throughhole, and the waveguiding wall each include at least one projection which projects inward;

the projection is interposed between the pair of vertical portions, and a leading end of the projection constitutes at least a part of the lateral portion;

the cross sections of the first throughhole, the second throughhole, and the waveguiding wall, as taken along the electrically conductive surface, each further include at least a pair of vertical portions extending in another direction intersecting the one direction, and the lateral portion interconnects the pair of vertical portions; and

when a central wavelength of the band in free space is λ

o, a thickness of the waveguiding wall at a center of the lateral portion is not less than 0.8 times as large as λ

o/4 and not more than 1.2 times as large as λ

o/4.

13. The waveguide device of claim 9, wherein,

the electrically conductive surface is planar;

the first throughhole extends through the first electrically conductive member perpendicularly to the electrically conductive surface; and

the second throughhole extends through the second electrically conductive member along the axial direction of the first throughhole.

14. The waveguide device of claim 5, wherein

cross sections of the first throughhole, the second throughhole, and the waveguiding wall, as taken along the electrically conductive surface, each include a lateral portion extending in one direction;

and

when a central wavelength of the band in free space is λ

o, a thickness of the waveguiding wall at a center of the lateral portion is not less than 0.8 times as large as λ

o/4 and not more than 1.2 times as large as λ

o/4.

15. The waveguide device of claim 1, wherein,

the waveguiding wall is split into a first portion and a second portion;

the first electrically conductive member and the first portion are portions of a single-piece body; and

the second electrically conductive member and the second portion are portions of another single-piece body.

16. The waveguide device of claim 15, wherein a height of the first portion is greater than that of the second portion.

17. The waveguide device of claim 1, wherein

the waveguiding wall connects to the first electrically conductive member;

and

there is a gap between the waveguiding wall and the second conductive member.

18. The waveguide device of claim 1, wherein

the waveguiding wall connects to the first electrically conductive member;

the first electrically conductive member and the waveguiding wall are portions of a single-piece body; and

there is a gap between the waveguiding wall and the second conductive member.

19. The waveguide device of claim 1, wherein cross sections of the first throughhole, the second throughhole, and the waveguiding wall, as taken along the electrically conductive surface, each include a lateral portion extending in one direction.

20. The waveguide device of claim 19, wherein,

the second electrically conductive member has an electrically conductive surface on a side opposite from the plurality of electrically conductive rods;

the waveguide device further comprises a third electrically conductive member;

the third electrically conductive member includes

a waveguide member having an electrically-conductive waveguide face opposing the electrically conductive surface of the second electrically conductive member, and

a second plurality of electrically conductive rods each having a leading end opposing the electrically conductive surface of the second electrically conductive member, the second plurality of electrically conductive rods being on both sides of the waveguide member; and

the waveguide face opposes the second throughhole at a site on the waveguide face.

21. The waveguide device of claim 19, wherein,

the second electrically conductive member includes, on a side opposite from the plurality of electrically conductive rods, a second plurality of electrically conductive rods and a waveguide member having an electrically-conductive waveguide face;

the waveguide device further comprises a third electrically conductive member having an electrically conductive surface opposing leading ends of the second plurality of electrically conductive rods and the waveguide face; and

the second throughhole is open at an end of the waveguide face of the waveguide member or another site.

22. The waveguide device of claim 19, further comprising a further electrically conductive member on a side of the first electrically conductive member opposite from the second electrically conductive member, the further electrically conductive member having an electrically conductive surface, wherein,

the first electrically conductive member includes

a waveguide member having an electrically-conductive waveguide face opposing the electrically conductive surface of the further electrically conductive member, the waveguide member propagating the electromagnetic wave which propagates in the first throughhole, and

a plurality of electrically conductive rods each having a leading end opposing the electrically conductive surface of the further electrically conductive member, the plurality of electrically conductive rods being on both sides of the waveguide member.

23. An antenna device comprising:

the waveguide device of claim 19; and

at least one antenna element that is connected to a waveguide in the waveguiding wall of the waveguide device, the at least one antenna element being used for at least one of transmission and reception.

24. A radar comprising:

the antenna device of claim 23; and

a microwave integrated circuit that is connected to the antenna device.

25. The waveguide device of claim 1, wherein

the waveguiding wall is split into a first portion and a second portion;

the first electrically conductive member and the first portion are portions of a single-piece body;

the second electrically conductive member and the second portion are portions of another single-piece body;

cross sections of the first throughhole, the second throughhole, and the waveguiding wall, as taken along the electrically conductive surface, each include a lateral portion extending in one direction and at least a pair of vertical portions extending in another direction intersecting the one direction, and

the lateral portion interconnects the pair of vertical portions.

26. The waveguide device of claim 1, wherein, among the plurality of electrically conductive rods, the second electrically conductive member further includes a waveguide member having an electrically-conductive waveguide face opposing the electrically conductive surface.

27. The waveguide device of claim 1, wherein,

the waveguiding wall is split into a first portion that connects to the first electrically conductive member and a second portion that connects to the second electrically conductive member;

and

among the plurality of electrically conductive rods, the second electrically conductive member further includes a waveguide member having an electrically-conductive waveguide face opposing the electrically conductive surface.

28. The waveguide device of claim 1, wherein,

cross sections of the first throughhole, the second throughhole, and the waveguiding wall, as taken along the electrically conductive surface, each include a lateral portion extending in one direction;

and

among the plurality of electrically conductive rods, the second electrically conductive member further includes a waveguide member having an electrically-conductive waveguide face opposing the electrically conductive surface.

29. The waveguide device of claim 28, wherein the cross sections of the first throughhole, the second throughhole, and the waveguiding wall, as taken along the electrically conductive surface, each further include at least a pair of vertical portions extending in another direction intersecting the one direction, and the lateral portion interconnects the pair of vertical portions.

30. The waveguide device of claim 29,

among the plurality of electrically conductive rods, the second electrically conductive member further includes a waveguide member having an electrically-conductive waveguide face opposing the electrically conductive surface;

inner wall surfaces of the first throughhole, the second throughhole, and the waveguiding wall each include at least one projection which projects inward; and

the projection is interposed between the pair of vertical portions, and a leading end of the projection constitutes at least a part of the lateral portion.

31. The waveguide device of claim 28, wherein,

the cross sections of the first throughhole, the second throughhole, and the waveguiding wall, as taken along the electrically conductive surface, each further include at least a pair of vertical portions extending in another direction intersecting the one direction, and the lateral portion interconnects the pair of vertical portions;

a central wavelength of the band in free space is λ

o, and a thickness of the waveguiding wall at a center of the lateral portion is not less than 0.8 times as large as λ

o/4 and not more than 1.2 times as large as λ

o/4;

the second electrically conductive member has an electrically conductive surface on a side opposite from the plurality of electrically conductive rods;

the waveguide device further comprises

a third electrically conductive member including a second plurality of electrically conductive rods each having a leading end opposing the electrically conductive surface of the second electrically conductive member, the third electrically conductive member having a third throughhole which overlaps the second throughhole as viewed along an axial direction of the second throughhole, and

an electrically-conductive further waveguiding wall at least partially surrounding a space between the second throughhole and the third throughhole, the further waveguiding wall being surrounded by the second plurality of electrically conductive rods and allowing the electromagnetic wave to propagate between the second throughhole and the third throughhole;

a height of the further waveguiding wall is less than λ

m/2; and

a distance between an electrically conductive rod among the second plurality of electrically conductive rods that is adjacent to the further waveguiding wall and an outer periphery of the further waveguiding wall is less than λ

m/2.

32. The waveguide device of claim 1, wherein,

cross sections of the first throughhole, the second throughhole, and the waveguiding wall, as taken along the electrically conductive surface, each include a lateral portion extending in one direction;

a height of the first portion is greater than that of the second portion; and

among the plurality of electrically conductive rods, the second electrically conductive member further includes a waveguide member having an electrically-conductive waveguide face opposing the electrically conductive surface.

33. The waveguide device of claim 1, wherein,

the waveguiding wall connects to the first electrically conductive member;

there is a gap between the waveguiding wall and the second conductive member; and

the waveguiding wall and the first conductive member are portions of a single-piece body.

34. The waveguide device of claim 1, wherein

among the plurality of electrically conductive rods, the second electrically conductive member further includes a waveguide member having an electrically-conductive waveguide face opposing the electrically conductive surface;

cross sections of the first throughhole, the second throughhole, and the waveguiding wall, as taken along the electrically conductive surface, each include a lateral portion extending in one direction and at least a pair of vertical portions extending in another direction intersecting the one direction;

the lateral portion interconnects the pair of vertical portions; and

a central wavelength of the band in free space is λ

o, and a thickness of the waveguiding wall at a center of the lateral portion is not less than 0.8 times as large as λ

o/4 and not more than 1.2 times as large as λ

o/4.

35. The waveguide device of claim 1, wherein,

the second electrically conductive member has an electrically conductive surface on a side opposite from the plurality of electrically conductive rods;

the waveguide device further comprises

a third electrically conductive member including a second plurality of electrically conductive rods each having a leading end opposing the electrically conductive surface of the second electrically conductive member, the third electrically conductive member having a third throughhole which overlaps the second throughhole as viewed along an axial direction of the second throughhole, and

an electrically-conductive further waveguiding wall at least partially surrounding a space between the second throughhole and the third throughhole, the further waveguiding wall being surrounded by the second plurality of electrically conductive rods and allowing the electromagnetic wave to propagate between the second throughhole and the third throughhole;

a height of the further waveguiding wall is less than λ

m/2; and

a distance between an electrically conductive rod among the second plurality of electrically conductive rods that is adjacent to the further waveguiding wall and an outer periphery of the further waveguiding wall is less than λ

m/2.

36. The waveguide device of claim 35, wherein,

a gap exists between the further waveguiding wall and the second electrically conductive member or the third electrically conductive member;

and

a thickness of the further waveguiding wall at a top surface thereof is less than λ

m/2.

37. The waveguide device of claim 35, wherein,

a gap exists between the further waveguiding wall and the second electrically conductive member or the third electrically conductive member;

a thickness of the further waveguiding wall at a top surface thereof is less than λ

m/2; and

at least one of the second electrically conductive member and the third electrically conductive member, and at least a portion of the further waveguiding wall, are portions of a single-piece body.

38. The waveguide device of claim 1, wherein

the second electrically conductive member has an electrically conductive surface on a side opposite from the plurality of electrically conductive rods;

the waveguide device further comprises

a third electrically conductive member including a second plurality of electrically conductive rods each having a leading end opposing the electrically conductive surface of the second electrically conductive member, the third electrically conductive member having a third throughhole which overlaps the second throughhole as viewed along an axial direction of the second throughhole, and

an electrically-conductive further waveguiding wall at least partially surrounding a space between the second throughhole and the third throughhole, the further waveguiding wall being surrounded by the second plurality of electrically conductive rods and allowing the electromagnetic wave to propagate between the second throughhole and the third throughhole;

a height of the further waveguiding wall is less than λ

m/2;

a distance between an electrically conductive rod among the second plurality of electrically conductive rods that is adjacent to the further waveguiding wall and an outer periphery of the further waveguiding wall is less than λ

m/2;

cross sections of the first throughhole, the second throughhole, and the waveguiding wall, as taken along the electrically conductive surface, each include a lateral portion extending in one direction; and

the further waveguiding wall connects to at least one of the second electrically conductive member and the third electrically conductive member.

39. The waveguide device of claim 1, wherein

the second electrically conductive member has an electrically conductive surface on a side opposite from the plurality of electrically conductive rods;

the waveguide device further comprises

a third electrically conductive member including a second plurality of electrically conductive rods each having a leading end opposing the electrically conductive surface of the second electrically conductive member, the third electrically conductive member having a third throughhole which overlaps the second throughhole as viewed along an axial direction of the second throughhole, and

an electrically-conductive further waveguiding wall at least partially surrounding a space between the second throughhole and the third throughhole, the further waveguiding wall being surrounded by the second plurality of electrically conductive rods and allowing the electromagnetic wave to propagate between the second throughhole and the third throughhole;

a height of the further waveguiding wall is less than λ

m/2;

a distance between an electrically conductive rod among the second plurality of electrically conductive rods that is adjacent to the further waveguiding wall and an outer periphery of the further waveguiding wall is less than λ

m/2;

cross sections of the first throughhole, the second throughhole, and the waveguiding wall, as taken along the electrically conductive surface, each include a lateral portion extending in one direction; and

at least one of the second electrically conductive member and the third electrically conductive member, and at least a portion of the further waveguiding wall, are portions of a single-piece body.