CN210628457U - Dielectric waveguide filter - Google Patents
Dielectric waveguide filter Download PDFInfo
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- CN210628457U CN210628457U CN201921770523.9U CN201921770523U CN210628457U CN 210628457 U CN210628457 U CN 210628457U CN 201921770523 U CN201921770523 U CN 201921770523U CN 210628457 U CN210628457 U CN 210628457U
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- waveguide filter
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- 238000002955 isolation Methods 0.000 claims abstract description 33
- 239000002184 metal Substances 0.000 claims abstract description 25
- 229910052751 metal Inorganic materials 0.000 claims abstract description 25
- 239000011248 coating agent Substances 0.000 claims abstract description 19
- 238000000576 coating method Methods 0.000 claims abstract description 19
- 238000006880 cross-coupling reaction Methods 0.000 claims abstract description 19
- 238000007747 plating Methods 0.000 claims description 15
- 239000000463 material Substances 0.000 claims description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 3
- 229910010293 ceramic material Inorganic materials 0.000 claims description 3
- 229910052802 copper Inorganic materials 0.000 claims description 3
- 239000010949 copper Substances 0.000 claims description 3
- 229910052709 silver Inorganic materials 0.000 claims description 3
- 239000004332 silver Substances 0.000 claims description 3
- 238000010168 coupling process Methods 0.000 abstract description 24
- 238000005859 coupling reaction Methods 0.000 abstract description 24
- 230000008878 coupling Effects 0.000 abstract description 23
- 230000002093 peripheral effect Effects 0.000 description 8
- 238000004891 communication Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 125000006850 spacer group Chemical group 0.000 description 2
- 238000007772 electroless plating Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
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Abstract
The application belongs to the technical field of filters and provides a dielectric waveguide filter, wherein a metal coating is covered on the surface of the dielectric waveguide filter, the dielectric waveguide filter includes at least three resonance units including at least one first resonance unit located at a cross-coupling pole and a plurality of second resonance units not located at the cross-coupling pole, a frequency blind hole and a through hole are arranged in the first resonance unit, an isolation ring is arranged at the through hole, at least one isolation ring exposed out of the metal coating is arranged at the through hole along the circumferential direction, therefore, the working mode of the filter is opposite to that of the adjacent resonance units, capacitive coupling among the resonance units is realized, and the problems of complex realization mode, difficult debugging and the like of the existing filter in the aspects of improving the frequency selection and out-of-band rejection characteristics of the filter are solved.
Description
Technical Field
The application relates to the technical field of filters, in particular to a dielectric waveguide filter.
Background
With the continuous development of modern communication technology, the performance index requirements of the filter are higher and higher. The dielectric waveguide filter has small size, high Q value, low cost and other features, and may be used in communication system with high miniaturization and integration level. However, with the continuous development of multi-frequency systems, the requirements for the frequency selection characteristic and the out-of-band rejection characteristic of the filter are also higher and higher.
However, the conventional filter has problems of complicated implementation mode, difficult debugging and the like in the aspects of improving the frequency selection and the out-of-band rejection characteristic of the filter.
SUMMERY OF THE UTILITY MODEL
The application aims to provide a dielectric waveguide filter, and aims to solve the problems that an existing filter is complex in implementation mode, difficult to debug and the like in the aspects of improving frequency selection and out-of-band rejection characteristics of the filter.
The embodiment of the application provides a dielectric waveguide filter, dielectric waveguide filter surface covering has the metallic coating, dielectric waveguide filter includes at least three resonance unit, at least three resonance unit includes that at least one is located the first resonance unit of cross coupling pole and a plurality of non-second resonance unit that are located the cross coupling pole, be equipped with frequency blind hole and through-hole in the first resonance unit, through-hole department is equipped with along its circumferencial direction at least one expose in the spacing collar of metallic coating.
Optionally, the isolation ring is located on an inner wall of the through hole or a peripheral area of the opening.
Optionally, the through hole is of a multi-stage stepped structure.
Optionally, the isolation ring is located on a step surface of at least one step of the multi-step structure.
Optionally, the isolation ring is located on a connecting surface between at least one adjacent stepped surface.
Optionally, the adjacent steps in the multi-step structure have the same shape.
Optionally, the through hole is cylindrical or prismatic in shape.
Optionally, the metal plating layer is made of metallic silver or metallic copper.
Optionally, the dielectric body in the dielectric waveguide filter is made of a ceramic material.
The embodiment of the application also provides another dielectric waveguide filter, the surface of the dielectric waveguide filter is covered with a metal coating, the dielectric waveguide filter comprises two resonance units, one of the resonance units comprises a frequency blind hole and a through hole, and at least one isolating ring exposed out of the metal coating is arranged at the through hole along the circumferential direction of the through hole.
In the dielectric waveguide filter that this application provided, dielectric waveguide filter surface covering has the metallic coating, dielectric waveguide filter includes at least three resonance unit, at least three resonance unit includes that at least one is located the first resonance unit of cross coupling pole and a plurality of non-second resonance unit that is located the cross coupling pole, be equipped with frequency blind hole and through-hole in the first resonance unit, through-hole department is equipped with the cage washer, through-hole department is equipped with along its circumferencial direction at least one expose in the cage washer of metallic coating to make its mode of operation opposite with the mode of adjacent resonance unit, realize the capacitive coupling between the resonance unit, solved current filter in the aspect of improving filter frequency selection and outband rejection characteristics realization mode complicated, debugging difficulty scheduling problem.
Drawings
Fig. 1 is a schematic top view of a dielectric waveguide filter according to a first embodiment of the present application;
fig. 2 is a schematic top view of a dielectric waveguide filter according to a second embodiment of the present application;
fig. 3 is a schematic perspective view of a dielectric waveguide filter according to a third embodiment of the present application;
fig. 4 is a schematic perspective view of a dielectric waveguide filter according to a fourth embodiment of the present application;
fig. 5 is a schematic perspective view of a dielectric waveguide filter according to a fifth embodiment of the present application;
fig. 6 is a schematic perspective view of a dielectric waveguide filter according to a sixth embodiment of the present application;
fig. 7 is a schematic perspective view of a dielectric waveguide filter according to a seventh embodiment of the present application;
fig. 8 is a perspective view of a dielectric waveguide filter according to an eighth embodiment of the present application.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.
In the description of the present application, it is to be understood that the terms "first", "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.
The embodiment of the application provides a dielectric waveguide filter, dielectric waveguide filter surface covering has the metallic coating, dielectric waveguide filter includes two resonance units, one of them resonance unit includes frequency blind hole and through-hole, through-hole department is equipped with along its circumferencial direction at least one expose in the spacing collar of metallic coating.
In this embodiment, the dielectric waveguide filter includes two resonant units, and a frequency blind hole and a through hole are provided in any one of the resonant units, and at least one isolation ring exposed out of the metal plating layer is provided at the through hole along a circumferential direction thereof, so that a working mode of the resonant unit is a TE102 mode, and at this time, a working mode of the other resonant unit is a TE101 mode, thereby implementing capacitive coupling between the two resonant units.
For example, fig. 1 is a schematic diagram of a dielectric waveguide filter provided in an embodiment of the present application, and referring to fig. 1, the dielectric waveguide filter in the embodiment includes a resonance unit 11 and a resonance unit 12, a coupling window 101 is opened on a dielectric body 10, the resonance unit 11 is communicated with the resonance unit 12 through the coupling window 101, the resonance unit 11 includes a frequency blind hole 111, the resonance unit 12 includes a frequency blind hole 121 and a through hole 122, wherein, at least one isolating ring 123 exposed out of the metal coating is arranged at the through hole 122 along the circumferential direction, the isolation ring 123 forms a closed-loop gap along the inner wall or open peripheral region of the through-hole 122, so that the resonant unit 11 operates in a mode opposite to that of the resonant unit 12, the operating mode of the resonant unit 12 is in the TE102 mode, and the operating mode of the resonant unit 11 is in the TE101 mode, so that capacitive coupling between the resonant unit 11 and the resonant unit 12 is realized.
The embodiment of the application also provides another dielectric waveguide filter, the dielectric waveguide filter surface is covered with the metal coating, the dielectric waveguide filter includes at least three resonance unit, at least three resonance unit includes that at least one is located the first resonance unit of cross coupling pole and a plurality of non-second resonance unit that are located the cross coupling pole, be equipped with frequency blind hole and through-hole in the first resonance unit, through-hole department is equipped with along its circumferencial direction at least one expose in the spacer ring of metal coating.
In this embodiment, the dielectric waveguide filter includes at least three resonant units, and a frequency blind via and a through via are disposed in a first resonant unit located at a cross-coupling pole, so that a working mode of the first resonant unit is opposite to a working mode of a second resonant unit not located at the cross-coupling pole, for example, the working mode of the first resonant unit is a TE102 mode, and working modes of a plurality of second resonant units not located at the cross-coupling pole are TE101 modes, thereby implementing capacitive coupling between the first resonant unit and the second resonant unit.
Fig. 2 is a schematic diagram of another dielectric waveguide filter provided in an embodiment of the present application, and referring to fig. 2, a dielectric body 20 in the embodiment is covered with a metal plating layer, a coupling window 201 is opened on the dielectric body 20, six resonance units are formed through the coupling window 201, the six resonance units include a resonance unit 21, a resonance unit 22, a resonance unit 23, a resonance unit 24, a resonance unit 25, and a resonance unit 26, where the resonance unit 21, the resonance unit 22, the resonance unit 23, the resonance unit 24, the resonance unit 25, and the resonance unit 26 all include a frequency blind hole, for example, the resonance unit 21 includes a frequency blind hole 211, the resonance unit 22 includes a frequency blind hole 221, the resonance unit 23 includes a frequency blind hole 231, the resonance unit 24 includes a frequency blind hole 241, the resonance unit 25 includes a frequency blind hole 251, the resonance unit 26 includes a frequency blind hole 261, the resonant unit 23 is located at a cross-coupling pole, the through hole 231 is arranged in the resonant unit 23, and the through hole 231 is provided with at least one isolation ring 232 exposed out of the metal plating layer along the circumferential direction thereof, the isolation ring 232 is not plated with the metal plating layer, so that the dielectric body 20 is exposed, the working mode of the resonant unit 23 is in a TE102 mode, and the working modes of the resonant unit 22 and the resonant unit 26 are both in a TE101 mode, so that capacitive coupling between the resonant unit 23 and the resonant unit 26 is realized.
Further, referring to fig. 2, the coupling window 201 in the present embodiment may include three sub-coupling windows, which are respectively in a cross shape, an L shape, and a circular shape, so as to divide the dielectric body 20 into six resonant units.
Further, the shape of the coupling window 201 may also be an oval through-hole slot, a square, or any other window shape.
In one embodiment, the isolation ring 232 is located on the inner wall or opening peripheral region of the through hole 231.
In one embodiment, referring to fig. 3, the isolation ring 232 may be located on an inner wall of the through hole 231, and arranged around an inner circle of the through hole 231 to form a closed-loop gap, the isolation ring 232 is formed by electroless plating metal in the area of the closed-loop gap, and the operation mode of the resonant unit 23 located at the cross-coupling pole is located in the TE102 mode, so that it is opposite to the operation mode of the front and rear cavities, and the capacitive coupling between the resonant unit 23 and the resonant unit 26 is achieved.
Further, referring to fig. 3, in the present embodiment, the resonant frequency of the resonant cavity can also be adjusted by providing blind port holes in the frequency blind holes in the resonant unit 24 and the resonant unit 25. For example, the blind port hole 242 is provided in the blind tuning hole 241 in the resonance unit 24, the blind port hole 252 is provided in the blind tuning hole 252 in the resonance unit 25, and the resonance frequency thereof is adjusted by adjusting the size and depth of the blind port hole.
Further, the size and shape of the isolation ring 232 can be determined by the coupling amount, and the coupling amount is larger when the isolation ring 232 has a larger area, i.e. the area of the electroless metal plating layer is larger, and the coupling amount is larger when the electroless metal plating layer has a larger area or position.
Further, the shape of the isolation ring 232 may be circular, prismatic, or any other shape.
In one embodiment, referring to fig. 4, the isolation ring 232 may also be located on the upper surface of the dielectric body 20 and arranged around the through hole 231, the isolation ring 232 exposed out of the metal plating layer is formed by not plating the metal plating layer on the peripheral region of the opening, and the dielectric body 20 is exposed, so that the operation mode of the resonant unit 23 located at the cross-coupling pole is opposite to the operation mode of the resonant unit 26 located at the non-cross-coupling pole, and the resonant unit 23 is located in the TE102 mode, so that the operation mode is opposite to the operation mode of the front and back cavities, thereby implementing capacitive coupling between the resonant unit 23 and the resonant unit 26.
In one embodiment, referring to fig. 5, the isolation ring 232 is located at the opening peripheral region of the through hole 231, the opening peripheral region is located at the lower surface of the dielectric body 20 and is arranged around the through hole 231, the isolation ring 232 exposed out of the metal plating layer is formed by not plating the metal plating layer on the opening peripheral region of the through hole 231 located at the lower surface of the dielectric body 20, and the dielectric body 20 is exposed, so that the operation mode of the resonant unit 23 is located in the TE102 mode, which is opposite to the operation mode of the front and rear cavities, and the capacitive coupling between the resonant unit 23 and the resonant unit 26 is realized.
In one embodiment, the position of the isolation ring 232 may be a combination of at least two schematic positions shown in fig. 3, fig. 4 and fig. 5, for example, referring to fig. 6, two isolation rings 232 are disposed at the through hole 231, wherein one isolation ring 232 is disposed on the inner wall of the through hole 231, and the other isolation ring 232 is disposed in a closed loop area of the through hole 231 in the opening peripheral area of the upper surface of the dielectric body 20, in this way, the operation mode of the resonant unit 23 is also set to be in the TE102 mode, which is opposite to the operation mode of the front and back cavities, and the capacitive coupling between the resonant unit 23 and the resonant unit 26 is realized.
In one embodiment, the through hole 231 may have a multi-step structure. In this embodiment, the through hole 231 is configured as a multi-step structure to form a step through hole, wherein the multi-step structure includes multi-step steps having different inner diameters, each step is formed by step surfaces along the circumferential direction of the through hole, the step surfaces of each step form a closed curved surface along the depth direction of the through hole, a connecting surface is further disposed between adjacent step surfaces, and the step surfaces of each step and the connecting surface between adjacent step surfaces form the inner wall of the through hole 231, for example, as shown in fig. 7, when the multi-step structure is a two-step structure, the inner diameter of the upper step is larger than the inner diameter of the lower step, and the upper step and the lower step are both cylindrical, at this time, the isolation ring 232 may be located on the step surfaces of the upper step or the lower step, further, the isolation ring 232 may also be located on the step surfaces of the upper step and the lower step at the same time, at this time, the inner wall of the, the plurality of non-contact 232 may be disposed on the step surface of each step and the connection surface between the adjacent step surfaces in any number.
In one embodiment, the cage 232 is located on a step face of at least one step of the multi-step structure. If the through hole 231 is of a multi-step structure, the isolation ring 232 is formed on the step surface of at least one step in the multi-step structure, so that the working mode of the resonant unit 23 can be located in the TE102 mode, which is opposite to the working mode of the front cavity and the rear cavity, and the capacitive coupling between the resonant unit 23 and the resonant unit 26 is realized.
In one embodiment, the spacer 232 is located at a connection surface between at least one adjacent stepped surface of the multi-step stepped structure. In this embodiment, a connection surface between adjacent stepped surfaces is a region where adjacent stepped surfaces in the multi-step structure are communicated, for example, referring to fig. 7, a stepped connection surface is provided between an upper step and a lower step to communicate, and the connection surface of the adjacent step forms a closed ring surface with a hole at the center, further, in an embodiment, the connection surface is perpendicular to the depth direction of the through hole 231, and the isolation ring 232 is formed on the connection surface, so that the working mode of the resonant unit 23 can be located in the TE102 mode, which is opposite to the working mode of the front and rear cavities, and capacitive coupling between the resonant unit 23 and the resonant unit 26 is achieved.
Further, in an embodiment, the isolation ring 232 in this embodiment may be a combination of at least two schematic positions shown in fig. 3, fig. 4 and fig. 7, or any number of combinations, for example, referring to fig. 8, two isolation rings 232 are disposed at the through hole 231, one isolation ring 232 is located in a closed loop region of the upper step inner wall in the through hole 231, and the other isolation ring 232 is located in a closed loop region of the step connection surface, by which the operation mode of the resonant unit 23 can also be located in the TE102 mode, which is opposite to the operation mode of the front and rear cavities, so as to realize the capacitive coupling between the resonant unit 23 and the resonant unit 26.
Further, in one embodiment, the multi-step structure may also include a plurality of steps having different shapes, for example, adjacent steps of the multi-step structure have different shapes, an upper step is cylindrical, and a lower step is prismatic.
In one embodiment, the through-hole 231 is cylindrical or prismatic in shape. Further, the shape of the through hole 231 may be any other shape, and for example, the shape of the through hole 231 may be an elliptical groove or the like.
In one embodiment, the material of the metal plating layer is metallic silver or metallic copper.
In one embodiment, the material of the dielectric body 20 is a ceramic material.
In the dielectric waveguide filter that this application provided, dielectric waveguide filter surface covering has the metallic coating, dielectric waveguide filter includes at least three resonance unit, at least three resonance unit includes that at least one is located the first resonance unit of cross coupling pole and a plurality of non-second resonance unit that is located the cross coupling pole, be equipped with frequency blind hole and through-hole in the first resonance unit, through-hole department is equipped with the cage washer, through-hole department is equipped with along its circumferencial direction at least one expose in the cage washer of metallic coating to make its mode of operation opposite with the mode of adjacent resonance unit, realize the capacitive coupling between the resonance unit, solved current filter in the aspect of improving filter frequency selection and outband rejection characteristics realization mode complicated, debugging difficulty scheduling problem.
The above description is only exemplary of the present application and should not be taken as limiting the present application, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.
Claims (10)
1. A dielectric waveguide filter is characterized in that a metal coating is covered on the surface of the dielectric waveguide filter, the dielectric waveguide filter comprises at least three resonance units, the at least three resonance units comprise at least one first resonance unit located at a cross coupling pole and a plurality of second resonance units not located at the cross coupling pole, a frequency blind hole and a through hole are formed in the first resonance unit, and at least one isolation ring exposed out of the metal coating is arranged at the through hole along the circumferential direction of the through hole.
2. A dielectric waveguide filter according to claim 1 wherein the cage is located on an inner wall of the via or in the region of the opening periphery.
3. The dielectric waveguide filter of claim 1 wherein the via is a multi-step structure.
4. A dielectric waveguide filter according to claim 3 wherein the cage is located at the step face of at least one step of the multi-step structure.
5. A dielectric waveguide filter according to claim 3 wherein the cage is located at the connection face between at least one adjacent stepped face.
6. A dielectric waveguide filter according to claim 3 wherein adjacent steps in the multi-step structure are of the same shape.
7. The dielectric waveguide filter according to claim 1, wherein the through-hole has a cylindrical or prismatic shape.
8. The dielectric waveguide filter of claim 1 wherein the material of the metal plating is metallic silver or metallic copper.
9. A dielectric waveguide filter according to claim 1 wherein the material of the dielectric body in the dielectric waveguide filter is a ceramic material.
10. A dielectric waveguide filter is characterized in that a metal coating is covered on the surface of the dielectric waveguide filter, the dielectric waveguide filter comprises two resonance units, one resonance unit comprises a frequency blind hole and a through hole, and at least one isolation ring exposed out of the metal coating is arranged at the through hole along the circumferential direction of the through hole.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921770523.9U CN210628457U (en) | 2019-10-21 | 2019-10-21 | Dielectric waveguide filter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921770523.9U CN210628457U (en) | 2019-10-21 | 2019-10-21 | Dielectric waveguide filter |
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| CN210628457U true CN210628457U (en) | 2020-05-26 |
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| CN201921770523.9U Active CN210628457U (en) | 2019-10-21 | 2019-10-21 | Dielectric waveguide filter |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110729534A (en) * | 2019-10-21 | 2020-01-24 | 摩比科技（深圳）有限公司 | Dielectric waveguide filter |
| WO2022110987A1 (en) * | 2020-11-27 | 2022-06-02 | Telefonaktiebolaget Lm Ericsson (Publ) | Dielectric filter |
-
2019
- 2019-10-21 CN CN201921770523.9U patent/CN210628457U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110729534A (en) * | 2019-10-21 | 2020-01-24 | 摩比科技（深圳）有限公司 | Dielectric waveguide filter |
| WO2022110987A1 (en) * | 2020-11-27 | 2022-06-02 | Telefonaktiebolaget Lm Ericsson (Publ) | Dielectric filter |
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