Coaxial resonator, filter, duplexer, and communication device

• US 20010045875A1
• Filed: 05/24/2001
• Published: 11/29/2001
• Est. Priority Date: 05/25/2000
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Okajima, Shingo, Hidaka, Seiji, Abe, Shin
• Granted Patent: US 6,894,587 B2
• Time in Patent Office: Days
• US Class Current: 333/134
• CPC Class Codes: H01P 1/2056 Comb filters or interdigital filters with metallised resonator holes in a dielectric block
• CPC Class Codes: H01P 7/04 Coaxial resonators

Abstract

A coaxial resonator according to an embodiment of the invention includes a tubular dielectric block, an inner conductor having a thin-film, multi-layer electrode structure, which is formed on an outer surface of a cylindrical shaft received in the hole of the tubular dielectric block, and an outer conductor formed on an outer surface of the tubular dielectric block. The cylindrical shaft is inserted into the hole in the dielectric block, and is held by a holding member and an outer frame.

Claims

1. A coaxial resonator comprising:

an inner conductor formed on an outer surface of a columnar element;

a dielectric element having a hole formed therein, the columnar element being disposed in the hole; and

an outer conductor formed on an outer surface of said dielectric element.

2. A coaxial resonator according to

claim 1

, wherein said inner conductor comprises a plurality of helical lines.

3. A coaxial resonator according to

claim 1

, wherein said inner conductor has a thin-film, multi-layer electrode structure in which thin-film conductor layers and thin-film dielectric layers are alternately laminated.

4. A coaxial resonator according to

claim 3

, wherein said inner conductor comprises a plurality of helical lines.

5. A coaxial resonator according to

claim 1

,

2

, 3 or 4, wherein said outer conductor is formed by alternately laminating thin-film conductor layers and thin-film dielectric layers.

6. A coaxial resonator according to

claim 5

, wherein the phase constants of lines for the thin-film conductor layers are substantially equal in said inner conductor and said outer conductor.

7. A coaxial resonator according to

claim 1

, further comprising a nonconducting element disposed between said columnar element and said dielectric element.

8. A filter comprising:

a plurality of coaxial resonators, each coaxial resonator comprising;

an inner conductor formed on an outer surface of a columnar element;

a dielectric element having a hole formed therein, the columnar element being disposed in the hole; and

an outer conductor formed on an outer surface of said dielectric element; and

an input/output device coupled to a predetermined coaxial resonator of said plurality of coaxial resonators.

9. A filter comprising:

a plurality of columnar elements, each columnar element having an inner conductor formed on an outer surface thereof;

a dielectric element having a plurality of holes formed therein, a respective one of said columnar elements being disposed in each said hole to form a corresponding coaxial resonator; and

an input/output device coupled to a predetermined coaxial resonator of said coaxial resonators.

10. A duplexer comprising:

a transmission filter disposed between a transmission signal input port and a transmission/reception signal input/output port; and

a reception filter disposed between the transmission/reception signal input/output port and a reception signal output port,

wherein at least one of said transmission filter and said reception filter includes a plurality of coaxial resonators, each coaxial resonator comprising;

an inner conductor formed on an outer surface of a columnar element;

a dielectric element having a hole formed therein, the columnar element being disposed in the hole; and

an outer conductor formed on an outer surface of said dielectric element; and

an input/output device coupled to a predetermined coaxial resonator of said plurality of coaxial resonators,

said input/output device being coupled to a corresponding one of said ports.

11. A communication device comprising:

a high-frequency circuit comprising a transmission circuit and a reception circuit; and

a duplexer comprising;

a transmission filter disposed between a transmission signal input port and a transmission/reception signal input/output port; and

a reception filter disposed between the transmission/reception signal input/output port and a reception signal output port,

wherein at least one of said transmission filter and said reception filter includes a plurality of coaxial resonators, each coaxial resonator comprising;

an inner conductor formed on an outer surface of a columnar element;

a dielectric element having a hole formed therein, the columnar element being disposed in the hole; and

an outer conductor formed on an outer surface of said dielectric element; and

an input/output device coupled to a predetermined coaxial resonator of said plurality of coaxial resonators,

said input/output device being coupled to a corresponding one of said ports.

12. A communication device comprising:

a high-frequency circuit comprising at least one of a transmission circuit and a reception circuit, said high-frequency circuit comprising;

a plurality of coaxial resonators, each coaxial resonator comprising;

an inner conductor formed on an outer surface of a columnar element;

a dielectric element having a hole formed therein, the columnar element being disposed in the hole; and

an outer conductor formed on an outer surface of said dielectric element; and

an input/output device coupled to a predetermined coaxial resonator of said plurality of coaxial resonators.