Ceramic waveguide filter including a plurality of resonant cavities coupled by a capacitive coupling structure and a method for manufacture

Patent metadata

Field	Value
Publication number	US-11901600-B2
Application number	US-202117329821-A
Country	US
Kind code	B2
Filing date	May 25, 2021
Priority date	Nov 26, 2018
Publication date	Feb 13, 2024
Grant date	Feb 13, 2024

Abstract

A ceramic waveguide filter comprises a plurality of resonant cavities defined by a plurality of through partition walls formed in a single ceramic block to divide sections of the ceramic block according to a pre-designated pattern, a plurality of resonant recesses formed in the sections of the plurality of resonant cavities divided by the through partition walls, a metal layer formed on an inner surface of each of the plurality of through partition walls, and input/output interfaces formed in two resonant cavities inputting and outputting signals among the plurality of resonant cavities.

First claim

What is claimed is:

1. A ceramic waveguide filter, comprising:
a plurality of resonant cavities defined by a plurality of through partition walls formed in a single ceramic block to divide sections of the ceramic block according to a pre-designated pattern;
a plurality of resonant recesses formed in the sections of the plurality of resonant cavities divided by the plurality of through partition walls;
a respective metal layer formed on a surface of each of the plurality of through partition walls; and
input/output interfaces formed in two of the plurality of resonant cavities for inputting and outputting signals among the plurality of resonant cavities,
a capacitive coupling structure on one surface of the ceramic block, spaced apart from the plurality of through partition walls and disposed between the plurality of resonant cavities, and
a metal layer formed on an inside of the capacitive coupling structure,
wherein the plurality of through partition walls pass through the ceramic block and divides the sections of the ceramic block such that the plurality of resonant cavities having the plurality of resonant recesses are defined,
wherein the plurality of resonant cavities are spaced apart from each other to filter a pre-designated frequency band while being sequentially coupled with adjacent resonant cavities through coupling windows formed by the plurality of through partition walls in response to the signal input through the input/output interfaces, and
wherein at least one resonant cavity from among the plurality of resonant cavities is disposed adjacent another one resonant cavity from among the plurality of resonant cavities, thereby allowing cross coupling to occur.

2. The ceramic waveguide filter according to claim 1 ,
wherein the plurality of resonant recesses are formed in each of centers of corresponding resonant cavity regions among the plurality of resonant cavities.

3. The ceramic waveguide filter according to claim 2 ,
wherein the input/output interfaces are formed in a form of through holes passing through the ceramic block.

4. The ceramic waveguide filter according to claim 1 ,
wherein the metal layer disposed respectively on the surface of each of the plurality of through partition walls has a thickness that is adjusted depending on the pre-designated frequency band.

5. The ceramic waveguide filter according to claim 1 ,
wherein the capacitive coupling structure comprises a coupling recess and a depth of the coupling recess is adjusted according to a frequency at which capacitive cross coupling is formed.

6. The ceramic waveguide filter according to claim 1 ,
wherein the capacitive coupling structure comprises a coupling hole, and
the coupling hole spaced apart from the plurality of through partition walls between the plurality of resonant cavities in which the cross coupling occurs, the coupling hole passing through the ceramic block; and
wherein a metal layer is formed inside of the coupling hole.

7. The ceramic waveguide filter according to claim 6 ,
wherein the coupling hole has an inner side formed in a stair-type structure, and
wherein the metal layer is formed in an area other than a pre-designated slot area facing one surface of the ceramic block on the inside of the coupling hole of the stair-type structure.

8. The ceramic waveguide filter according to claim 6 ,
wherein the ceramic waveguide filter further comprises
a conductive sticker attached to a region in which the coupling hole is formed on one surface of the ceramic block.

9. A method of manufacturing a ceramic waveguide filter, comprising:
in order to define a plurality of resonant cavities in a ceramic block, forming a plurality of through partition walls dividing sections of the ceramic block according to a pre-designated pattern;
forming a plurality of resonant recesses in the sections of the plurality of resonant cavities divided by the through partition walls;
forming a respective metal layer on a surface of each of the plurality of through partition walls;
forming input/output interfaces for inputting and outputting signals in two of the plurality of resonant cavities among the plurality of resonant cavities;
forming a capacitive coupling structure on one surface of the ceramic block and spaced apart from the plurality of through partition walls between resonant cavities; and
forming the metal layer on an inside of the capacitive coupling structure,
wherein the plurality of through partition walls pass through the ceramic block and divides the sections of the ceramic block such that the plurality of resonant cavities having the plurality of resonant recesses are defined,
wherein the plurality of resonant cavities are spaced apart from each other to filter a pre-designated frequency band while being sequentially coupled with adjacent resonant cavities through coupling windows formed by the plurality of through partition walls in response to the signal input through the input/output interfaces, and
wherein at least one resonant cavity from among the plurality of resonant cavities is disposed adjacent another one resonant cavity from among the plurality of resonant cavities, thereby allowing cross coupling to occur.

10. The method according to claim 9 ,
wherein the method of manufacturing a ceramic waveguide filter further comprises:
adjusting a thickness of the metal layer disposed on the surface of each of the plurality of through partition walls depending on the pre-designated frequency band.

11. The method according to claim 9 ,
wherein in the step of forming the plurality of resonant recesses,
the plurality of resonant recesses are formed in each of centers of corresponding resonant cavity regions among the plurality of resonant cavities.

12. The method according to claim 11 ,
wherein in the step of forming the input/output interfaces,
the input/output interfaces are formed in a form of through holes passing through the ceramic block.

13. The method according to claim 9 ,
wherein the capacitive coupling structure comprises
a coupling recess and
a depth of the coupling recess is adjusted according to a frequency at which capacitive cross coupling is formed.

14. The method according to claim 9 ,
wherein the capacitive coupling structure comprises a coupling hole; and the method of manufacturing a ceramic waveguide filter further comprises:
forming a coupling hole spaced apart from the plurality of through partition walls between resonant cavities in which the cross coupling occurs, the coupling hole passing through the ceramic block; and
forming the metal layer on an inner surface of the coupling hole.

15. The method according to claim 14 ,
wherein in the step of forming the coupling hole
an inside of the coupling hole is formed in a stair-type structure, and
wherein in the step of forming the metal layer on the inner surface of the coupling hole
the metal layer is formed in an area other than a pre-designated slot area facing one surface of the ceramic block on the inside of the coupling hole of the stair-type structure.

16. The method according to claim 15 ,
wherein the method of manufacturing a ceramic waveguide filter further comprises:
attaching a conductive sticker to a region in which the coupling hole is formed on one surface of the ceramic block.

Assignees

• Ace tech corp

Inventors

• Chun Dong Wan

Classifications

• H01P1/2088 Primary

  Integrated in a substrate · CPC title

• H01P1/163

  specifically adapted for selection or promotion of the TE01 circular-electric mode · CPC title

• H01P1/2002 Primary

  Dielectric waveguide filters (H01P1/212, H01P1/213, H01P1/215, H01P1/219 take precedence) · CPC title

• H01P3/13

  specially adapted for transmission of the TE01 circular-electric mode {(selection, promotion H01P1/163)} · CPC title

• H01P7/06

  Cavity resonators · CPC title