# US 11,121,695 B2 · Diplexer and multiplexer

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 11,121,695 B2
- Document ID: US11121695B2
- Status: Granted
- Kind: B2
- Application number: 16/607,480
- Filed: 2018-04-23
- Published: 2020-04-30
- Granted: 2021-09-14
- Earliest claimed: 2017-04-28
- Assignees: Fujikura Ltd.
- Applicants: Fujikura Ltd.
- Inventors: Yusuke Uemichi
- Web page: https://patentgrep.com/patent/US11121695B2

## CPC

- H01P 1/2088: {Integrated in a substrate}
- H03H 7/463: {Duplexers}
- H01P 1/2138: {using hollow waveguide filters (H01P1/2131 takes precedence)}
- H01P 3/121: {integrated in a substrate}
- H01P 5/18: consisting of two coupled guides, e.g. directional couplers
- H01P 5/181: {the guides being hollow waveguides}
- H01P 7/10: Dielectric resonators
- H03H 7/0161: {Bandpass filters (H03H7/12 takes precedence)}
- H01P: WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE (operating at optical frequencies G02B)
- H03H: IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS (waveguides, resonators, lines or other devices of the waveguide type H01P)

## Abstract

A diplexer (100) includes: first and second directional couplers (106A, 106B); and first and second filters (101A, 101B). The filters (101A, 101B) each include a plurality of resonators (110A to 150A, 110B to 150B) that are electromagnetically coupled. The resonators (110A to 150A, 110B to 150B) each have a broad wall that is in a shape of a circle or a regular polygon with six or more vertices, and two resonators, which are coupled together, of the resonators (110A to 150A, 110B to 150B) are arranged such that D<R1+R2 is satisfied, where R1 and R2 represent radii of circumcircles of the broad walls of the two resonators and D represents a center-to-center distance between the two resonators.

## Claims

### Claim 1

A diplexer comprising:
a first directional coupler that is comprised of a first waveguide and a second waveguide;
a second directional coupler that is comprised of a third waveguide and a fourth waveguide;
a first filter that resides between the first waveguide and the third waveguide; and
a second filter that resides between the second waveguide and the fourth waveguide,
the first filter and the second filter each including a plurality of resonators that are electromagnetically coupled,
the plurality of resonators each having a broad wall that is in a shape of a circle or a regular polygon with six or more vertices,
two resonators, which are coupled together, of the plurality of resonators being arranged such that D<R1+R2 is satisfied, where R1 and R2 represent radii of circumcircles of the broad walls of the two resonators and D represents a center-to-center distance between the two resonators,
wherein:
each of the plurality of resonators is formed by a pair of the broad walls and a narrow wall that resides between the pair of broad walls,
the pair of broad walls are constituted by a pair of conductor layers provided on opposite surfaces of a dielectric substrate, and
the narrow wall passes through the dielectric substrate and is constituted by a conductor post group via which the pair of broad walls are in electrical communication with each other.

### Claim 2 (depends on 1)

The diplexer according to claim 1, wherein the plurality of resonators include a first-pole resonator that has an input port and a last-pole resonator that has an output port, and the plurality of resonators are arranged such that the first-pole resonator and the last-pole resonator are adjacent to each other.

### Claim 3 (depends on 1)

The diplexer according to claim 1, wherein:
the plurality of resonators include a first-pole resonator that has an input port and a last-pole resonator that has an output port;
the first-pole resonator has a waveguide aperture that functions as the input port, the waveguide aperture being positioned on an opposite side of the first-pole resonator from the last-pole resonator such that the waveguide aperture intersects a straight line that passes through a center of the first-pole resonator and a center of the last-pole resonator; and
the last-pole resonator has a waveguide aperture that functions as the output port, the waveguide aperture being positioned on an opposite side of the last-pole resonator from the first-pole resonator such that the waveguide aperture intersects the straight line.

### Claim 4 (depends on 1)

The diplexer according to claim 1, wherein
the number of the plurality of resonators is an odd number.

### Claim 5 (depends on 1)

The diplexer according to claim 1, wherein at least one of the plurality of resonators further includes a projection made of a conductor, the projection projecting inward from one of a pair of the broad walls that form the at least one of the plurality of resonators.

### Claim 6 (depends on 1)

The diplexer according to claim 1, wherein:
the first filter and the second filter each have a passband which is a first frequency band; and
the diplexer further comprises a third filter that is comprised of a plurality of resonators electromagnetically coupled, that has a passband which is a second frequency band different from the first frequency band, and that is connected to an opposite end of the first waveguide from the first filter.

### Claim 7 (depends on 6)

The diplexer according to claim 6, wherein each of the plurality of resonators of the third filter is located on a circumference of a reference circle or located within the reference circle, the reference circle being any circle which encloses the first filter and the second filter and which has a diameter that is equal to or less than a distance from an opposite end of the second waveguide from the second filter to an opposite end of the fourth waveguide from the second filter.

### Claim 8 (depends on 6)

The diplexer according to claim 6, wherein:
each of the plurality of resonators of the third filter has a broad wall that is in a shape of a circle or a regular polygon with six or more vertices; and
two resonators, which are coupled together, of the plurality of resonators are arranged such that d<r1+r2 is satisfied, where r1 and r2 represent radii of circumcircles of the broad walls of the two resonators and d represents a center-to-center distance between the two resonators.

### Claim 9 (depends on 1)

A multiplexer comprising a plurality of the diplexers recited in claim 1.

### Claim 10

A diplexer comprising:
a first directional coupler that is comprised of a first waveguide and a second waveguide;
a second directional coupler that is comprised of a third waveguide and a fourth waveguide;
a first filter that resides between the first waveguide and the third waveguide; and
a second filter that resides between the second waveguide and the fourth waveguide,
the first filter and the second filter each including a plurality of resonators that are electromagnetically coupled,
the plurality of resonators each having a broad wall that is in a shape of a circle or a regular polygon with six or more vertices,
two resonators, which are coupled together, of the plurality of resonators being arranged such that D<R1+R2 is satisfied, where R1 and R2 represent radii of circumcircles of the broad walls of the two resonators and D represents a center-to-center distance between the two resonators,
wherein at least one of the plurality of resonators further includes a projection made of a conductor, the projection projecting inward from one of a pair of the broad walls that form the at least one of the plurality of resonators.

### Claim 11

A diplexer comprising:
a first directional coupler that is comprised of a first waveguide and a second waveguide;
a second directional coupler that is comprised of a third waveguide and a fourth waveguide;
a first filter that resides between the first waveguide and the third waveguide; and
a second filter that resides between the second waveguide and the fourth waveguide,
the first filter and the second filter each including a plurality of resonators that are electromagnetically coupled,
the plurality of resonators each having a broad wall that is in a shape of a circle or a regular polygon with six or more vertices,
two resonators, which are coupled together, of the plurality of resonators being arranged such that D<R1+R2 is satisfied, where R1 and R2 represent radii of circumcircles of the broad walls of the two resonators and D represents a center-to-center distance between the two resonators,
wherein:
the first filter and the second filter each have a passband which is a first frequency band; and
the diplexer further comprises a third filter that is comprised of a plurality of resonators electromagnetically coupled, that has a passband which is a second frequency band different from the first frequency band, and that is connected to an opposite end of the first waveguide from the first filter.

### Claim 12 (depends on 11)

The diplexer according to claim 11, wherein each of the plurality of resonators of the third filter is located on a circumference of a reference circle or located within the reference circle, the reference circle being any circle which encloses the first filter and the second filter and which has a diameter that is equal to or less than a distance from an opposite end of the second waveguide from the second filter to an opposite end of the fourth waveguide from the second filter.

### Claim 13 (depends on 11)

The diplexer according to claim 11, wherein:
each of the plurality of resonators of the third filter has a broad wall that is in a shape of a circle or a regular polygon with six or more vertices; and
two resonators, which are coupled together, of the plurality of resonators are arranged such that d<r1+r2 is satisfied, where r1 and r2 represent radii of circumcircles of the broad walls of the two resonators and d represents a center-to-center distance between the two resonators.