Transmission line device

• US 10,714,802 B2
• Filed: 06/25/2018
• Issued: 07/14/2020
• Est. Priority Date: 06/26/2017
• Status: Active Grant

• Current Assignee: Nidec Corporation, Wgr Co., Ltd.
• Original Assignee: Wgr Co., Ltd.
• Inventors: Kirino, Hideki, Kamo, Hiroyuki
• Primary Examiner(s): Pascal, Robert J
• Assistant Examiner(s): Glenn, Kimberly E
• Application Number:
  US16/016,830
• Publication Number:
  US 20180375182A1
• Time in Patent Office: 750 Days
• CPC Class Codes: H01P 1/211 Waffle-iron filters; Corrugated structures
• CPC Class Codes: H01P 3/088 Stacked transmission lines
• CPC Class Codes: H01P 3/121 integrated in a substrate
• CPC Class Codes: H01P 5/024 between hollow waveguides
• CPC Class Codes: H01P 5/107 Hollow-waveguide/strip-line transitions
• CPC Class Codes: H01Q 1/3233 particular used as part of a sensor or in a security system, e.g. for automotive radar, navigation systems
• CPC Class Codes: H01Q 13/22 Longitudinal slot in boundary wall of waveguide or transmission line H01Q13/203 takes precedence
• CPC Class Codes: H01Q 15/008 said selective devices having Sievenpipers' mushroom elements
• CPC Class Codes: H01Q 3/443 varying the phase velocity along a leaky transmission line frequency scanning H01Q3/22; non-resonant leaky-waveguide or transmission-line aerials H01Q13/20

Abstract

A transmission line device includes: a plurality of electrically conductive members stacked with interspaces therebetween, the plurality of electrically conductive members including three or more electrically conductive members; and a plurality of artificial magnetic conductors each located between two adjacent electrically conductive members among the plurality of electrically conductive members. Among the plurality of electrically conductive members, at least one electrically conductive member located between two endmost electrically conductive members is shaped as a plate having at least one slit. At least a portion of the plurality of artificial magnetic conductors is located around the at least one slit to suppress leakage of an electromagnetic wave propagating along the at least one slit.

Claims

1. A transmission line device comprising:

a plurality of electrically conductive members stacked with interspaces therebetween, the plurality of electrically conductive members including three or more electrically conductive members; and

a plurality of artificial magnetic conductors each located between two adjacent electrically conductive members among the plurality of electrically conductive members,

wherein,

among the plurality of electrically conductive members, at least one electrically conductive member located between two endmost electrically conductive members is shaped as a plate having at least one slit; and

at least a portion of the plurality of artificial magnetic conductors is located around the at least one slit to suppress leakage of an electromagnetic wave propagating along the at least one slit.

2. The transmission line device of claim 1, wherein each of the plurality of artificial magnetic conductors includes a plurality of electrically conductive rods, each of the plurality of electrically conductive rods being connected to one of two electrically conductive members that are included in the plurality of electrically conductive members and located on opposite sides of the artificial magnetic conductor and having a leading end opposing another of the two electrically conductive members.

3. The transmission line device of claim 2, wherein one or more of the plurality of electrically conductive rods are connected to the at least one electrically conductive member having the at least one slit and disposed around the at least one slit.

4. The transmission line device of claim 1, further comprising at least one microwave IC which is mounted to the at least one electrically conductive member having the at least one slit, the at least one microwave IC having a plurality of signal terminals respectively connected to a plurality of sites between which the at least one slit is interposed.

5. The transmission line device of claim 2, further comprising at least one microwave IC which is mounted to the at least one electrically conductive member having the at least one slit, the at least one microwave IC having a plurality of signal terminals respectively connected to a plurality of sites between which the at least one slit is interposed.

6. The transmission line device of claim 3, further comprising at least one microwave IC which is mounted to the at least one electrically conductive member having the at least one slit, the at least one microwave IC having a plurality of signal terminals respectively connected to a plurality of sites between which the at least one slit is interposed.

7. The transmission line device of claim 6, wherein,

the at least one microwave IC is mounted on a first surface of the at least one electrically conductive member;

and

the plurality of electrically conductive rods in one of the plurality of artificial magnetic conductors are disposed on a second surface of the at least one electrically conductive member, the second surface being opposite to the first surface.

8. The transmission line device of claim 1, wherein one end of the at least one slit reaches an edge of the at least one electrically conductive member and functions as an antenna element.

9. The transmission line device of claim 4, wherein one end of the at least one slit reaches an edge of the at least one electrically conductive member and functions as an antenna element.

10. The transmission line device of claim 1, wherein,

the at least one electrically conductive member has a plurality of slits;

and

one end of each of the plurality of slits reaches an edge of the at least one electrically conductive member and functions as an antenna element.

11. The transmission line device of claim 4, wherein,

the at least one electrically conductive member has a plurality of slits;

and

one end of each of the plurality of slits reaches an edge of the at least one electrically conductive member and functions as an antenna element.

12. The transmission line device of claim 5, wherein,

the at least one microwave IC is mounted on a first surface of the at least one electrically conductive member;

the plurality of electrically conductive rods in one of the plurality of artificial magnetic conductors are disposed on a second surface of the at least one electrically conductive member, the second surface being opposite to the first surface;

the at least one electrically conductive member includes a plurality of slits;

the plurality of slits extend in parallel to one another;

the at least one electrically conductive member has a groove at an edge of the at least one electrically conductive member, the groove being located between two adjacent slits among the plurality of slits;

the plurality of electrically conductive rods are located around each of the plurality of slits to suppress leakage of electromagnetic waves propagating along the plurality of slits; and

a depth of the groove is not less than λ

o/8 and not more than λ

o/2, where λ

o is a free-space wavelength at a center frequency of a band of the electromagnetic waves propagating along the plurality of slits.

13. The transmission line device of claim 10, wherein,

the plurality of slits extend in parallel to one another;

the at least one electrically conductive member has a groove at an edge of the at least one electrically conductive member, the groove being located between two adjacent slits among the plurality of slits;

the plurality of electrically conductive rods are located around each of the plurality of slits to suppress leakage of electromagnetic waves propagating along the plurality of slits; and

a depth of the groove is not less than λ

o/8 and not more than λ

o/2, where λ

o is a free-space wavelength at a center frequency of a band of the electromagnetic waves propagating along the plurality of slits.

14. The transmission line device of claim 1, wherein,

the plurality of electrically conductive members comprise four or more electrically conductive members;

among the plurality of electrically conductive members, at least two electrically conductive members located between the two endmost electrically conductive members are each shaped as a plate having at least one slit functioning as a transmission line; and

at least a portion of the plurality of artificial magnetic conductors is located around each of the slits of the at least two electrically conductive members to suppress leakage of the electromagnetic wave propagating along the slit.

15. The transmission line device of claim 4, wherein,

the plurality of electrically conductive members comprise four or more electrically conductive members;

among the plurality of electrically conductive members, at least two electrically conductive members located between the two endmost electrically conductive members are each shaped as a plate having at least one slit functioning as a transmission line; and

at least a portion of the plurality of artificial magnetic conductors is located around each of the slits of the at least two electrically conductive members to suppress leakage of the electromagnetic wave propagating along the slit.

16. The transmission line device of claim 14, wherein an end of each of the slits of the at least two electrically conductive members reaches an edge of the electrically conductive member having the slit and functions as an antenna element.

17. The transmission line device of claim 15, wherein an end of each of the slits of the at least two electrically conductive members reaches an edge of the electrically conductive member having the slit and functions as an antenna element.

18. The transmission line device of claim 4, wherein,

the plurality of electrically conductive members comprise four or more electrically conductive members;

among the plurality of electrically conductive members, at least two electrically conductive members located between the two endmost electrically conductive members are each shaped as a plate and each having a plurality of slits;

at least a portion of the plurality of artificial magnetic conductors is located around each of the slits of the at least two electrically conductive members to suppress leakage of the electromagnetic wave propagating along the slit;

an end of each of the plurality of slits reaches an edge of the electrically conductive member having the slit and functions as an antenna element; and

the ends of the plurality of slits of the at least two electrically conductive members are arranged in a two-dimensional array.

19. The transmission line device of claim 7, wherein,

the plurality of electrically conductive members comprise four or more electrically conductive members;

among the plurality of electrically conductive members, at least two electrically conductive members located between the two endmost electrically conductive members are each shaped as a plate and each having a plurality of slits;

at least a portion of the plurality of artificial magnetic conductors is located around each of the slits of the at least two electrically conductive members to suppress leakage of the electromagnetic wave propagating along the slit;

an end of each of the plurality of slits reaches an edge of the electrically conductive member having the slit and functions as an antenna element; and

the ends of the plurality of slits of the at least two electrically conductive members are arranged in a two-dimensional array.

20. The transmission line device of claim 16, wherein,

each of the at least two electrically conductive members has a plurality of slits;

and

ends of the plurality of slits of the at least two electrically conductive members are arranged in a two-dimensional array.