Bidirectional coupler, monitor circuit, and front end circuit

• US 10,461,392 B2
• Filed: 05/31/2018
• Issued: 10/29/2019
• Est. Priority Date: 06/01/2017
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Kim, Ryangsu, Shigeno, Yasushi
• Primary Examiner(s): Takaoka, Dean O
• Application Number:
  US15/994,741
• Publication Number:
  US 20180351228A1
• Time in Patent Office: 516 Days
• Field of Search: 333109, 333116, 333117
• CPC Class Codes: H01P 5/18 consisting of two coupled guides, e.g. directional couplers
• CPC Class Codes: H01P 5/185 Edge coupled lines
• CPC Class Codes: H03H 9/70 Multiple-port networks for connecting several sources or loads, working on different frequencies or frequency bands, to a common load or source
• CPC Class Codes: H04B 1/0057 using diplexing or multiplexing filters for selecting the desired band
• CPC Class Codes: H04B 3/52 Systems for transmission between fixed stations via waveguides

Abstract

A bidirectional coupler includes a multilayer board, a first main line, a second main line, a third main line, and an sub line. The sub line includes a first line portion, an even number of second line portions, and an even number of third line portions. One half of the second line portions is provided between the first line portion and one end of the sub line. The other half of the second line portions is provided between the first line portion and the other end of the sub line. One half of the third line portions is provided between the one half of the second line portions and the one end of the sub line. The other half of the third line portions is provided between the other half of the second line portions and the other end of the sub line.

Claims

1. A bidirectional coupler comprising:

a multilayer board; and

a first main line, a second main line, a third main line, and a sub line that are provided in or on the multilayer board, wherein;

the sub line comprises;

a first line portion that is electromagnetically coupled to the first main line,

an even number of second line portions that are electromagnetically coupled to the second main line, and

an even number of third line portions that are electromagnetically coupled to the third main line,

a first half of the even number of second line portions are provided between the first line portion and a first end of the sub line, and a second half of the even number of second line portions are provided between the first line portion and a second end of the sub line,

a first half of the even number of third line portions are provided between the first half of the second line portions and the first end of the sub line, and a second half of the even number of third line portions are provided between the second half of the second line portions and the second end of the sub line.

2. The bidirectional coupler according to claim 1, wherein the first line portion comprises a pair of first line portions.

3. The bidirectional coupler according to claim 2, wherein an electrical length between a mid-point of the sub line and one of the pair of first line portions is approximately equal to an electrical length between the mid-point and another of the pair of first line portions.

4. The bidirectional coupler according to claim 1, wherein:

the even number of second line portions comprise a pair of second line portions, and

an electrical length between a mid-point of the sub line and one of the pair of second line portions is approximately equal to an electrical length between the mid-point and another of the pair of second line portions.

5. The bidirectional coupler according to claim 1, wherein:

the even number of third line portions comprise a pair of third line portions, and

an electrical length between a mid-point of the sub line and one of the pair of third line portions is approximately equal to an electrical length between the mid-point and another of the pair of third line portions.

6. The bidirectional coupler according to claim 1, wherein:

the even number of second line portions comprise a pair of second line portions, and

the sub line is arranged in or on the multilayer board in line symmetry with a line of symmetry passing through the multilayer board in a plan view, each of the pair of second line portions being arranged on opposite sides of the line of symmetry and at corresponding symmetrical positions about the line of symmetry.

7. The bidirectional coupler according to claim 1, wherein:

the even number of third line portions comprise a pair of third line portions, and

the sub line is arranged in or on the multilayer board in line symmetry with a line of symmetry passing through the multilayer board in a plan view, each of the pair of third line portions being arranged on opposite sides of the line of symmetry and at corresponding symmetrical positions about the line of symmetry.

8. The bidirectional coupler according to claim 2, wherein the sub line is arranged in or on the multilayer board in line symmetry with a line of symmetry passing through the multilayer board in a plan view, each of the pair of first line portions being arranged on opposite sides of the line of symmetry and at corresponding symmetrical positions about the line of symmetry.

9. The bidirectional coupler according to claim 2, wherein each of the pair of first line portions are connected to each other by an inductor.

10. The bidirectional coupler according to claim 1, wherein a width of at least one of the first line portion, the second line portion, and the third line portion is different from a width of another of the first line portion, the second line portion, and the third line portion.

11. A monitor circuit comprising the bidirectional coupler according to claim 1.

12. A front end circuit comprising:

the monitor circuit according to claim 11;

an antenna terminal connected to the monitor circuit; and

a filter connected to the monitor circuit.

13. The bidirectional coupler according to claim 2, wherein:

the even number of second line portions comprise a pair of second line portions, and

an electrical length between a mid-point of the sub line and one of the pair of second line portions is approximately equal to an electrical length between the mid-point and another of the pair of second line portions.

14. The bidirectional coupler according to claim 3, wherein:

the even number of second line portions comprise a pair of second line portions, and

an electrical length between a mid-point of the sub line and one of the pair of second line portions is approximately equal to an electrical length between the mid-point and another of the pair of second line portions.

15. The bidirectional coupler according to claim 2, wherein:

the even number of third line portions comprise a pair of third line portions, and

an electrical length between a mid-point of the sub line and one of the pair of third line portions is approximately equal to an electrical length between the mid-point and another of the pair of third line portions.

16. The bidirectional coupler according to claim 2, wherein:

the even number of second line portions comprise a pair of second line portions, and

the sub line is arranged in or on the multilayer board in line symmetry with a line of symmetry passing through the multilayer board in a plan view, each of the pair of second line portions being arranged on opposite sides of the line of symmetry and at corresponding symmetrical positions about the line of symmetry.

17. The bidirectional coupler according to claim 2, wherein:

the even number of third line portions comprise a pair of third line portions, and

the sub line is arranged in or on the multilayer board in line symmetry with a line of symmetry passing through the multilayer board in a plan view, each of the pair of third line portions being arranged on opposite sides of the line of symmetry and at corresponding symmetrical positions about the line of symmetry.

18. The bidirectional coupler according to claim 3, wherein the sub line is arranged in or on the multilayer board in line symmetry with a line of symmetry passing through the multilayer board in a plan view, each of the pair of first line portions being arranged on opposite sides of the line of symmetry and at corresponding symmetrical positions about the line of symmetry.

19. The bidirectional coupler according to claim 3, wherein each of the pair of first line portions are connected to each other by an inductor.

20. The bidirectional coupler according to claim 2, wherein a width of at least one of the first line portion, the second line portion, and the third line portion is different from a width of another of the first line portion, the second line portion, and the third line portion.