CN116169447B

CN116169447B - Cavity filter

Info

Publication number: CN116169447B
Application number: CN202211649998.9A
Authority: CN
Inventors: 谢懿非
Original assignee: Comba Telecom Technology Guangzhou Ltd; Jingxin RF Technology Guangzhou Co ltd
Current assignee: Comba Telecom Technology Guangzhou Ltd; Jingxin RF Technology Guangzhou Co ltd
Priority date: 2022-12-21
Filing date: 2022-12-21
Publication date: 2024-07-16
Anticipated expiration: 2042-12-21
Also published as: CN116169447A

Abstract

The present disclosure relates to the technical field of filters, and provides a cavity filter, including: a metal resonant column; a dielectric resonating column; the filter comprises a filter body, wherein an in-line cavity is formed in the filter body, and a coupling piece with a cantilever structure is arranged on one side wall of the in-line cavity; the metal resonant columns and the dielectric resonant columns are respectively arranged in the straight-line cavities at two sides of the coupling piece and are used for respectively forming a metal resonator and a dielectric resonator; through set up the coupling piece that is cantilever structure between metal resonance post and dielectric resonance post, make the coupling piece have stronger structural stability and connection stability, simultaneously, can realize the strong coupling effect of in-line intracavity dielectric resonator and metal resonator, and it is little to cavity filter's insertion loss influence.

Description

Cavity filter

Technical Field

The disclosure relates to the technical field of filters, and in particular relates to a cavity filter.

Background

The filter is a frequency selective device and is an integral part of the communication equipment. In order to improve filter inhibition and meanwhile give consideration to product cost, a dielectric resonator is generally introduced into a traditional metal filter to achieve the aim, the metal resonator and the dielectric resonator in the traditional cavity filter are often arranged in a triangle shape, so that a certain included angle is formed between the metal resonator and at least one dielectric resonator when the metal resonator and the dielectric resonators are arranged, the distance between the metal resonator and the adjacent dielectric resonator is shortened, the coupling effect is improved, in the practical application process, the influence of space layout is limited, the situation that all resonant cavities are on the same straight line is often encountered when the filter is designed, and at the moment, cross coupling between the metal resonator and the dielectric resonator is often difficult to realize or great insertion loss is caused.

Disclosure of Invention

In order to solve the above technical problem, the present disclosure provides a cavity filter, including:

a metal resonant column;

a dielectric resonating column;

The filter comprises a filter body, wherein an in-line cavity is formed in the filter body, and a coupling piece with a cantilever structure is arranged on one side wall of the in-line cavity; and the metal resonant columns and the dielectric resonant columns are respectively arranged in the straight-line cavities at two sides of the coupling piece and are used for forming a metal resonator and a dielectric resonator respectively.

Optionally, the coupling piece is a coupling partition wall, the coupling partition wall is formed on a side wall of the in-line cavity, and the coupling partition wall extends from the side wall toward the in-line cavity between the metal resonant column and the dielectric resonant column.

Optionally, the coupling partition wall is integrally formed with the filter body.

Optionally, a suspension height between the coupling partition wall and the bottom wall of the in-line cavity, and a size of the coupling partition wall are related to a coupling bandwidth.

Optionally, the coupling is a metal coupling piece.

Optionally, a boss is formed on one side wall of the in-line cavity; one end of the metal coupling piece is connected with the boss, and the other end of the metal coupling piece is a cantilever end.

Optionally, the height of the boss and the size of the metal sheet are related to the coupling bandwidth.

Optionally, a bending structure is formed on the metal coupling piece, and the bending structure is folded towards the dielectric resonance column.

Optionally, the dielectric resonance column includes base, dielectric resonance pole and resonance unit, the base with the bottom surface butt in straight-line chamber, dielectric resonance pole sets up on the base, resonance unit cover is established on the dielectric resonance pole, just resonance unit butt is in on the dielectric resonance pole, at least part the coupling piece with resonance unit is just right.

Optionally, the in-line cavity is provided with a convex rib on the other side wall corresponding to the coupling piece, the convex rib is opposite to the coupling piece and keeps a distance, and the distance is related to the coupling bandwidth.

Optionally, the coupling device comprises two metal resonators, one dielectric resonator is arranged between the two metal resonators, and the coupling piece is respectively arranged between the dielectric resonator and the two adjacent metal resonators.

Optionally, the two coupling pieces between the dielectric resonator and the adjacent two metal resonators are disposed on opposite sides or the same side of the in-line cavity.

Compared with the prior art, the technical scheme provided by the embodiment of the disclosure has the following advantages:

According to the cavity filter provided by the embodiment of the disclosure, the in-line cavity is formed in the filter body and is used for arranging the metal resonant column and the dielectric resonant column in the in-line cavity so as to form the metal resonator and the dielectric resonator, so that the purposes of improving the inhibition and reducing the insertion loss are realized; through set up the coupling piece that is cantilever structure between metal resonance post and dielectric resonance post, make the coupling piece have stronger structural stability and connection stability, simultaneously, can realize the strong coupling effect of in-line intracavity dielectric resonator and metal resonator, and it is little to cavity filter's insertion loss influence.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the disclosure and together with the description, serve to explain the principles of the disclosure.

In order to more clearly illustrate the embodiments of the present disclosure or the solutions in the prior art, the drawings that are required for the description of the embodiments or the prior art will be briefly described below, and it will be obvious to those skilled in the art that other drawings can be obtained from these drawings without inventive effort.

FIG. 1 is a schematic diagram of a cavity filter according to an embodiment of the disclosure;

FIG. 2 is a bobbin diagram of a cavity filter according to an embodiment of the present disclosure;

FIG. 3 is a schematic view of a metal coupling sheet according to an embodiment of the present disclosure;

FIG. 4 is a schematic view of a metal coupling sheet with a bending structure according to an embodiment of the disclosure;

FIG. 5 is a schematic diagram of a first embodiment of the disclosure;

FIG. 6 is a schematic diagram of a second embodiment of the disclosure;

FIG. 7 is a schematic diagram of a third embodiment of the present disclosure;

FIG. 8 is a schematic diagram of a corresponding curve of a first embodiment of the disclosure;

FIG. 9 is a schematic diagram of a second embodiment of the present disclosure;

Fig. 10 is a schematic diagram of a corresponding curve of a third embodiment of the present disclosure.

1, A filter body; 11. an in-line cavity; 12. a boss; 13. convex ribs; 2. a metal resonator; 21. a metal resonant column; 22. a fixed screw; 3. a dielectric resonator; 31. a dielectric resonating column; 311. a base; 313. a resonance unit; 314. adjusting a screw; 4. a coupling; 41. a coupling partition; 42. a metal coupling sheet; 5. and a connecting piece.

Detailed Description

In order that the above objects, features and advantages of the present disclosure may be more clearly understood, a further description of aspects of the present disclosure will be provided below. It should be noted that, without conflict, the embodiments of the present disclosure and features in the embodiments may be combined with each other.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure, but the present disclosure may be practiced otherwise than as described herein; it will be apparent that the embodiments in the specification are only some, but not all, embodiments of the disclosure.

As shown in fig. 1 and 2, the present embodiment provides a cavity filter, including: a metal resonant column 21; a dielectric resonator column 31; the filter body 1, there is a straight cavity 11 in the filter body 1, the above-mentioned straight cavity 11 of the above-mentioned filter body 1 can also form the cavity of other structures, alternatively, the above-mentioned straight cavity 11 can be communicated with other cavities, there is a coupling piece 4 taking the form of cantilever structure on a sidewall of the straight cavity 11, the above-mentioned coupling piece 4 can be the cantilever structure installed on a sidewall of the straight cavity 11, also can be formed on a sidewall of the above-mentioned straight cavity 11 directly; adjacent to the coupling element 4, a metal resonant column 21 and a dielectric resonant column 31 are respectively disposed in the in-line cavities 11 on both sides of the coupling element 4, for respectively forming the metal resonator 2 and the dielectric resonator 3, and the in-line cavities 11 on both sides thereof can be separated into a metal resonant cavity and a dielectric resonant cavity by the coupling element 4.

In the cavity filter of the embodiment, the in-line cavity 11 is formed in the filter body 1, so that the metal resonator 2 and the dielectric resonator 3 are formed by arranging the metal resonator column 21 and the dielectric resonator column 31 in the in-line cavity 11, and the purposes of improving and inhibiting and reducing insertion loss are realized; through setting up the coupling piece 4 that is cantilever structure between metal resonance post 21 and dielectric resonance post 31, make coupling piece 4 have stronger structural stability and connection stability, simultaneously, can realize the strong coupling effect of dielectric resonator 3 and metal resonator 2 in the straight-line cavity 11, and it is little to cavity filter's insertion loss influence.

For example, the internal dielectric resonator 3 may be a TE-mode dielectric resonator 3, and correspondingly, the dielectric resonator column 31 is a TE-mode dielectric resonator column 31, where the TE-mode dielectric resonator 3 has advantages of high dielectric constant, high quality factor, small temperature coefficient of frequency, and the like, and has high stability and reliability.

In some embodiments, the coupling member 4 is a coupling partition wall 41, and the coupling partition wall 41 is formed on one side wall of the in-line cavity 11, that is, the coupling partition wall 41 is integrally formed with the filter body 1, and the coupling partition wall 41 extends from the side wall into the in-line cavity 11 between the metal resonant pillar 21 and the dielectric resonant pillar 31, preferably, the coupling partition wall 41 is perpendicular to the side wall of the in-line cavity 11 to which it is connected, and the coupling partition wall 41 may be formed by cutting on the filter body 1 with a T-type tool by using a CNC processing platform, for example. Through the above arrangement, the connection point between the coupling partition 41 and the filter body 1 is avoided, so that the coupling partition 41 is complete in structure and uniform in material, the coupling degree can be improved, the insertion loss is reduced, meanwhile, the assembly process is omitted, and the production efficiency of the cavity filter is improved.

In other embodiments, the coupling partition 41 is integrally formed with the filter body 1, and the coupling partition 41 may be integrally formed with the filter body 1 by casting, for example. Through making coupling partition 41 and filter body 1 integrated into one piece, can guarantee the good contact between coupling partition 41 and the filter body 1, avoid the gap roughness to cause the problem of signal energy loss, in addition, can also simplify production process, reduce cavity filter's manufacturing cost.

It should be noted that, the suspension height between the coupling partition wall 41 and the bottom wall of the in-line cavity 11, and the size of the coupling partition wall 41 are related to the coupling bandwidth, so the adjustment of the coupling bottom width can be achieved by changing the suspension height of the coupling partition wall 41 and the size of the coupling partition wall 41.

In the embodiment shown in fig. 3, the coupling element 4 is a metal coupling piece 42, and specifically, the metal coupling piece 42 may be connected to a side wall of the filter body 1 through the connecting element 5 or the clamping element. The coupling bandwidth can be flexibly adjusted by adjusting the length and width of the metal coupling piece 42 so as to adapt to different application scenes.

In the embodiment shown in fig. 4, a boss 12 is formed on one side wall of the in-line cavity 11; one end of the metal coupling piece 42 is connected with the boss 12, the other end is a cantilever end, the metal coupling piece 42 can be installed on one side of the boss 12, which is opposite to the bottom surface of the filter body 1, through the connecting piece 5, and the connecting piece 5 can be specifically a screw, a bolt, a rivet, and the like. By arranging the boss 12, a mounting surface can be provided for the metal coupling piece 42, so that the metal coupling piece 42 can be connected with the filter body 1 conveniently, and the stability of the metal coupling piece 42 is improved.

It should be noted that the height of the boss 12 and the size of the metal coupling piece 42 are related to the coupling bandwidth, and the height of the metal coupling piece 42 may be controlled by changing the height of the boss 12 to further adjust the coupling bottom width, and in addition, the size of the metal coupling piece 42 may be redesigned to achieve the coupling bottom width adjustment.

In more detail, the metal coupling piece 42 is formed with a bending structure, and the bending structure is folded to the dielectric resonator column 31, so that the signal transmission area between the metal coupling piece 42 and the dielectric resonator column 31 can be increased by arranging the bending structure, and the coupling bandwidth can be further increased.

In some more specific embodiments, the dielectric resonator column 31 includes a base 311, a dielectric resonator rod and a resonator unit 313, the base 311 is abutted against the bottom surface of the in-line cavity 11, the dielectric resonator rod is disposed on the base 311, the resonator unit 313 is sleeved on the dielectric resonator rod, and the resonator unit 313 is abutted against the dielectric resonator rod, at least part of the coupling member 4 is opposite to the resonator unit 313, and the coupling member 4 is in a cantilever structure because the resonator unit 313 is disposed on the base 311, i.e. the coupling member 4 is suspended relative to the bottom surface of the in-line cavity 11, so that the coupling effect can be ensured by disposing the resonator unit 313 opposite to the coupling member 4. Alternatively, the orthographic projection of the resonant cell 313 falls entirely on the coupling 4 so as to satisfy a larger coupling bandwidth; the metal resonance column 21 is provided with a fixed screw rod 22, the medium resonance column 31 is provided with an adjusting screw rod 314, and cover plates are arranged between the metal resonance column 21 and the fixed screw rod 22 and between the medium resonance column 31 and the adjusting screw rod 314, and the cover plates can be of an integral structure corresponding to the opening of the straight-line cavity 11; by rotating the adjusting screw 314, the expansion and contraction of the adjusting screw 314 can be controlled for controlling the frequency of the dielectric resonator column 31.

In more detail, in some embodiments, the cavity filter includes two metal resonators 2, one dielectric resonator 3 is disposed between two metal resonators 2, and the coupling element 4 is disposed between the dielectric resonator 3 and two adjacent metal resonators 2. A dielectric resonator 3 is arranged between two metal resonators 2 to be the minimum functional unit of the cavity filter, namely the number of the metal resonators 2 and the number of the dielectric resonators 3 can be multiple, wherein the number of the metal resonators 2 is not less than two, and one dielectric resonator 3 is arranged between every two metal resonators 2; not less than two metal resonators 2 are arranged in a straight line with the dielectric resonator 3.

In particular, when the coupling element 4 is connected on the same side of the in-line cavity 11 as shown in fig. 5, the filter produces a capacitive coupling on the left side of the passband as shown in fig. 7.

In the second embodiment, as shown in fig. 6, a coupling element 4 is disposed on one side wall of the in-line cavity 11, a rib 13 corresponding to the coupling element 4 is disposed on the other side wall of the in-line cavity 11, the rib 13 may be disposed opposite to the coupling element 4 or may be disposed in a staggered manner with respect to the coupling element 4, and the rib 13 may be connected between the top surface and the bottom surface of the in-line cavity 11 or may be partially protruded on the side wall of the in-line cavity 11; the ribs 13 are arranged opposite to the coupling element 4 and maintain a distance, the size of which is related to the coupling bandwidth. Specifically, by controlling the position of the protruding rib 13 relative to the coupling element 4 and the structure of the protruding rib 13, the size of the window between the metal resonant cavity and the dielectric resonant cavity can be controlled, so that the purpose of reducing the zero point on the left side of the passband as shown in fig. 9 is achieved, and the longitudinal suppression effect on the interference signal is more obvious.

In the third embodiment, as shown in fig. 7, two coupling members 4 between the dielectric resonator 3 and two adjacent metal resonators 2 are disposed on opposite sides or the same side of the in-line cavity 11, that is, at least two coupling members 4 are disposed on opposite sides of the in-line cavity 11, and when a plurality of coupling members 4 are disposed in the cavity filter, at least a part of the coupling members 4 are disposed on one side wall of the in-line cavity 11, and another part of the coupling members 4 are disposed on the other side wall opposite to the one side wall. Specifically, by disposing at least two coupling members 4 on opposite sides of the in-line cavity 11, as shown in fig. 10, capacitive coupling can be generated on the right side of the passband, and the effect of suppressing the interference signal can be improved.

It should be noted that, the first embodiment, the second embodiment and the third embodiment can be flexibly combined and selected according to specific design requirements of the cavity filter.

In the description of the embodiments of the present disclosure, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "height", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the embodiments of the present disclosure and to simplify the description, and do not indicate or imply that the structures or devices referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the embodiments of the present disclosure.

It should be noted that in this document, relational terms such as "first" and "second" and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

The foregoing is merely a specific embodiment of the disclosure to enable one skilled in the art to understand or practice the disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the disclosure. Thus, the present disclosure is not intended to be limited to the embodiments shown and described herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A cavity filter, comprising:

a metal resonant column (21);

A dielectric resonator column (31);

The filter comprises a filter body (1), wherein an in-line cavity (11) is formed in the filter body (1), and a coupling piece (4) with a cantilever structure is arranged on one side wall of the in-line cavity (11); adjacent to the coupling piece (4), the metal resonant columns (21) and the dielectric resonant columns (31) are respectively arranged in the straight-line cavities (11) at two sides of the coupling piece (4) and are used for respectively forming a metal resonator (2) and a dielectric resonator (3);

The coupling piece (4) is a coupling partition wall (41), the coupling partition wall (41) is formed on the side wall of the in-line cavity (11), and the coupling partition wall (41) extends from the side wall into the in-line cavity (11) between the metal resonant column (21) and the dielectric resonant column (31);

the suspension height between the coupling partition wall (41) and the bottom wall of the in-line cavity (11), and the size of the coupling partition wall (41) are related to the coupling bandwidth;

The number of the metal resonators (2) is two, one dielectric resonator (3) is arranged between the two metal resonators (2), the coupling pieces (4) are respectively arranged between the dielectric resonator (3) and the two adjacent metal resonators (2), and the two coupling pieces (4) are arranged on two opposite sides or the same side of the in-line cavity (11).

2. Cavity filter according to claim 1, characterized in that the coupling partition (41) is integrally formed with the filter body (1).

3. Cavity filter according to claim 1, characterized in that the coupling element (4) is a metal coupling plate (42).

4. A cavity filter according to claim 3, wherein a boss (12) is formed on a side wall of the inline cavity (11); one end of the metal coupling piece (42) is connected with the boss (12), and the other end is a cantilever end.

5. The cavity filter according to claim 4, wherein the height of the boss (12), the size of the metal coupling plate (42) is related to the coupling bandwidth.

6. A cavity filter according to claim 3, wherein the metal coupling piece (42) has a bending structure formed thereon, the bending structure being folded towards the dielectric resonator pillar (31).

7. The cavity filter according to claim 1, wherein the dielectric resonator column (31) comprises a base (311), a dielectric resonator rod and a resonant unit (313), the base (311) is abutted against the bottom surface of the in-line cavity (11), the dielectric resonator rod is arranged on the base (311), the resonant unit (313) is sleeved on the dielectric resonator rod, the resonant unit (313) is abutted against the dielectric resonator rod, and at least part of the coupling piece (4) is opposite to the resonant unit (313).

8. Cavity filter according to claim 1, characterized in that the in-line cavity (11) is provided with ribs (13) on the other side wall corresponding to the coupling element (4), the ribs (13) being arranged opposite the coupling element (4) and maintaining a spacing, the size of which is related to the coupling bandwidth.