CN111066198B

CN111066198B - Ceramic dielectric filter

Info

Publication number: CN111066198B
Application number: CN201980001851.9A
Authority: CN
Inventors: 刘磊; 王斌华; 叶荣; 廖东
Original assignee: Mobi Antenna Technologies Shenzhen Co Ltd; Shenzhen Shengyu Wisdom Network Technology Co Ltd; Mobi Technology Xian Co Ltd; Mobi Antenna Technologies Jian Co Ltd; Mobi Technology Shenzhen Co Ltd
Current assignee: Mobi Antenna Technologies Shenzhen Co Ltd; Shenzhen Shengyu Wisdom Network Technology Co Ltd; Mobi Technology Xian Co Ltd; Mobi Antenna Technologies Jian Co Ltd; Mobi Technology Shenzhen Co Ltd
Priority date: 2019-09-27
Filing date: 2019-09-27
Publication date: 2020-11-13
Anticipated expiration: 2039-09-27
Also published as: EP4037093A4; EP4037093A1; CN111066198A; WO2021056415A1

Abstract

A ceramic dielectric filter comprises at least one first resonant unit (100) and at least two second resonant units (200), wherein each first resonant unit (100) is provided with a first tuning blind hole (101) and a second tuning blind hole (102) on the side surface of a first opening, each second resonant unit (200) is provided with a third tuning blind hole (201) on the side surface of a second opening, the depth of the first tuning blind hole (101) and the depth of the second tuning blind hole (102) are both larger than that of the third tuning blind hole (201), the working mode of the first resonant unit (100) is a TE102 mode, the working mode of the second resonant unit (200) is a TE101 mode, and any first resonant unit (100) is at least capacitively coupled with one second resonant unit (200) and is at least inductively coupled with one second resonant unit (200). The ceramic dielectric filter can realize capacitive coupling without arranging additional accessories or structural features, and has the advantages of simple structure, easy realization and better frequency selection performance.

Description

Ceramic dielectric filter

Technical Field

The application belongs to the technical field of filters, and particularly relates to a ceramic dielectric filter.

Background

In a wireless communication system, a filter is an indispensable frequency selective device. The ceramic dielectric filter has compact volume and excellent performance, and thus has wide application foreground. However, compared with the inductive coupling, the conventional ceramic dielectric filter has difficulties such as a limited manner and a complex structure in realizing the capacitive coupling, which results in a poor frequency selectivity of the ceramic dielectric filter.

Technical problem

The application provides a ceramic dielectric filter, which aims to solve the problem that the frequency selection performance is poor due to the difficulties of mode limitation, complex structure and the like in the aspect of realizing capacitive coupling of the conventional ceramic dielectric filter.

Technical solution

In order to solve the technical problem, the embodiment of the application adopts the following technical scheme:

a ceramic dielectric filter comprises at least one first resonant unit and at least two second resonant units, wherein each first resonant unit is provided with a first open pore side surface, a first tuning blind hole and a second tuning blind hole which is arranged at a distance from the first tuning blind hole are arranged on the first open pore side surface, each second resonant unit is provided with a second open pore side surface which is arranged in parallel with the first open pore side surface and faces the same direction, a third tuning blind hole is arranged on the second open pore side surface, the depth of the first tuning blind hole and the depth of the second tuning blind hole are both larger than the depth of the third tuning blind hole, the working mode of the first resonant unit is a TE102 mode, the working mode of the second resonant unit is a TE101 mode, and any first resonant unit is at least capacitively coupled with one second resonant unit, and is inductively coupled with at least one of the second resonance units, and any one of the second resonance units is inductively coupled with at least one of the other second resonance units.

In the embodiment of the application, the first tuning blind hole is arranged between the center of the side surface of the first opening and the joint of the side surface of the first opening and the side surface of the second opening; and the second tuning blind hole is arranged between the center of the side surface of the first opening and the joint of the center of the side surface of the first opening and one of the other side surfaces of the second opening.

In the embodiment of the present application, the thicknesses of each of the first resonance units and each of the second resonance units are all set to be equal.

In an embodiment of the present application, a cross-sectional area of the first resonance unit on a side perpendicular to the first opening is greater than or equal to a cross-sectional area of the second resonance unit on a side perpendicular to the second opening.

In the embodiment of the present application, each of the first resonance units and each of the second resonance units are arranged in an array having at least two rows.

In the embodiment of the present application, each of the first resonance units and each of the second resonance units are integrally formed.

In the embodiment of the present application, the ceramic dielectric filter has at least one first separating through-groove formed at a junction between the first opening side and the second opening side, and the first separating through-groove can be used to separate the first resonant unit and the second resonant unit, so that the first resonant unit and the second resonant unit are not coupled at the first separating through-groove;

the ceramic dielectric filter is provided with at least one second separating through groove which is arranged in a penetrating manner at the joint of the two second open pore side surfaces, and the second separating through groove can be used for separating the two second resonance units so that the two second resonance units are not coupled at the second separating through groove.

In the embodiment of the application, the cross-sectional shape of the first tuning blind hole is circular.

In the embodiment of the application, the cross-sectional shape of the second tuning blind hole is circular.

In an embodiment of the present application, the first resonant unit includes a first resonant cavity made of a ceramic material and a first metal cavity wall made of a metal material, and the first metal cavity wall is wrapped on an outer surface of the first resonant cavity;

the second resonant unit comprises a second resonant cavity made of a ceramic material and a second metal cavity wall made of a metal material, and the outer surface of the second resonant cavity is coated with the second metal cavity wall.

In an embodiment of the present application, the first metal cavity wall is made of copper or silver.

In an embodiment of the present application, the second metal cavity wall is made of copper or silver.

In this embodiment, there are two first resonant units, seven second resonant units, and two first resonant units are spaced apart from each other, and any one of the first resonant units is capacitively coupled to one of the second resonant units and inductively coupled to the two second resonant units.

In this embodiment, there is one first resonance unit, seven second resonance units, and the first resonance unit is capacitively coupled to one second resonance unit and inductively coupled to the two second resonance units.

In an embodiment of the present invention, each of the first resonant units has a third opening side surface opposite to and facing the first opening side surface, each of the second resonant units has a fourth opening side surface opposite to and facing the second opening side surface, the ceramic dielectric filter has a signal access port opened on one of the third opening side surface and the fourth opening side surface, and a signal feed-out port opened on one of the remaining third opening side surface and the fourth opening side surface, the signal access port is used for inputting a signal, and the signal feed-out port is used for feeding out a signal.

Advantageous effects

The ceramic dielectric filter provided by the application has the technical effects that: the first resonant unit is provided with a first tuning blind hole and a second tuning blind hole which are arranged at intervals, the second resonant unit is provided with a third tuning blind hole, the first resonant unit can work in a loaded TE102 mode by adjusting the depth of the first tuning blind hole and the second tuning blind hole, and the second resonant unit can work in a loaded TE101 mode by adjusting the depth of the third tuning blind hole. The ceramic dielectric filter provided by the application can realize capacitive coupling without arranging additional accessories or structural features on the resonance unit, has a simple structure, is easy to realize, and has better frequency selection performance.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the description of the embodiments of the present application or the prior art will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present application, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic view of a ceramic dielectric filter according to an embodiment of the present application when viewed from the side of a first opening;

fig. 2 is a schematic view of a ceramic dielectric filter provided in an embodiment of the present application when viewed from the front side of a third opening;

FIG. 3 is a schematic view of a ceramic dielectric filter according to an embodiment of the present application;

FIG. 4 is a frequency response curve of a ceramic dielectric filter according to an embodiment of the present invention;

fig. 5 is a schematic view of a ceramic dielectric filter according to a second embodiment of the present application when viewed from the side of a first opening;

fig. 6 is a schematic view of a ceramic dielectric filter according to a second embodiment of the present application when viewed from the side of a third opening;

FIG. 7 is a schematic view of a ceramic dielectric filter according to the second embodiment of the present application;

fig. 8 is a frequency response curve of the ceramic dielectric filter according to the second embodiment of the present application.

The reference numbers illustrate:

embodiments of the present application

Reference will now be made in detail to embodiments of the present application, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary and intended to be used for explaining the present application and should not be construed as limiting the present application.

In the description of the present application, it is to be understood that the terms "length," "width," "upper," "lower," "left," "right," "top," "bottom," "inner," "outer," and the like are used in the orientations and positional relationships indicated in the drawings for the purpose of convenience and simplicity of description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the present application.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

In this application, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can include, for example, fixed connections, removable connections, or integral parts; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

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.

Example one

Referring to fig. 1-3, an embodiment of the present invention provides a ceramic dielectric filter, including at least one first resonant unit 100 and at least two second resonant units 200, each first resonant unit 100 having a first opening side, and having a first tuning blind hole 101 and a second tuning blind hole 102 spaced from the first tuning blind hole 101, each second resonant unit 200 having a second opening side parallel to and facing the first opening side, and having a third tuning blind hole 201 on the second opening side, wherein the depth of the first tuning blind hole 101 and the depth of the second tuning blind hole 102 are both greater than the depth of the third tuning blind hole 201, the operating mode of the first resonant unit 100 is a TE102 mode, the operating mode of the second resonant unit 200 is a TE101 mode, any first resonant unit 100 is capacitively coupled to at least one second resonant unit 200, and is inductively coupled to at least one of the second resonant units 200, and any one of the second resonant units 200 is inductively coupled to at least one of the other second resonant units 200.

The second resonant unit 200 is provided with a third tuning blind hole 201 on the second opening side, and the third tuning blind hole 201 can be used for generating capacitance loading, so that the second resonant unit 200 works in the TE101 mode. The third tuning blind hole 201 needs to be a blind hole, on one hand, a tuning margin can be reserved, and on the other hand, the resonant frequency of the second resonant unit 200 can be adjusted by changing the depth and/or diameter of the third tuning blind hole 201. Additionally, the third tuning blind hole 201 is required to be disposed at the center of the second opening side of the second resonant unit 200, and thus, it is beneficial to improve the precise control of the resonant frequency of the second resonant unit 200. Additionally, the cross-sectional shape of the third tuning blind hole 201 can be, but is not limited to, circular, square, and the like, and optionally, the cross-sectional shape of the third tuning blind hole 201 is circular in the present embodiment, so as to improve the processing convenience of the second resonance unit 200 and easily guarantee the processing precision of the third tuning blind hole 201.

The first resonance unit 100 is provided with a first tuning blind hole 101 and a second tuning blind hole 102 which are arranged at intervals, and both the first tuning blind hole 101 and the second tuning blind hole 102 can be used for generating capacitance loading. First tuning blind hole 101 and second tuning blind hole 102 all are the blind hole setting, and the degree of depth of first tuning blind hole 101 and second tuning blind hole 102 all is greater than the degree of depth setting of third tuning blind hole 201, so set up, on the one hand, can reserve the tuning margin, on the other hand, the accessible is adjusted the degree of depth of first tuning blind hole 101 and second tuning blind hole 102 for first resonant unit 100 can work in the TE102 mode after the loading, and can adjust the operating frequency under the TE102 mode that first resonant unit 100 was loaded. Moreover, the first tuning blind hole 101 and the second tuning blind hole 102 are arranged at intervals, and the working frequency of the TE102 mode loaded by the first resonance unit 100 can be adjusted to be spaced from the frequencies of the TE101 and other modes by adjusting the center distance between the first tuning blind hole 101 and the second tuning blind hole 102. Specifically, when the center distance between the first tuning blind via 101 and the second tuning blind via 102 is increased, the frequency-selective characteristic of the first resonant unit 100, such as the Q-factor, is improved, but the unwanted interference frequency, such as the TE101 mode frequency, is close to the operating frequency of the TE102 mode, which may have a negative effect on the operating frequency of the first resonant unit 100 in the TE102 mode; on the contrary, when the center distance between the first tuning blind via 101 and the second tuning blind via 102 is reduced, the frequency-selective characteristic of the first resonant unit 100, such as the Q-factor, will be slightly reduced, but the unwanted interference frequency, such as the frequency of TE101 mode, will be far away from the operating frequency of TE102 mode, so that the center distance between the first tuning blind via 101 and the second tuning blind via 102 needs to be designed in a balanced manner according to the specific use requirement.

Based on the above arrangement, the first resonant unit 100 operating in the TE102 mode will generate electromagnetic fields with opposite directions near the first tuning blind via 101 and the second tuning blind via 102, so that the first resonant unit 100 can generate capacitive coupling with one adjacent second resonant unit 200, and generate inductive coupling with opposite polarities with the other adjacent second resonant units 200. For example, as shown in fig. 1, the first resonant unit 100 at the lower left corner generates an electromagnetic field with an electromagnetic field direction set counterclockwise near the first tuning blind hole 101, and generates an electromagnetic field with an electromagnetic field direction set clockwise near the second tuning blind hole 102, and each second resonant unit 200 adjacent to the first resonant unit 100 generates an electromagnetic field with an electromagnetic field direction set clockwise near the third tuning blind hole 201, based on this arrangement, when the first resonant unit 100 at the lower left corner and the second resonant unit 200 at the upper left corner are coupled, the electromagnetic fields exposed to each other are opposite in direction, thereby generating capacitive coupling, and when the first resonant unit 100 at the lower left corner and the second resonant unit 200 at the upper right corner and the right corner thereof are coupled, the electromagnetic fields exposed to each other are the same in direction, thereby generating inductive coupling. Therefore, the ceramic dielectric filter provided in the embodiment of the present application can realize capacitive coupling and inductive coupling without greatly changing the structure and size of the first resonant unit 100 to obtain a desired filter frequency characteristic, and based on the frequency characteristic of the ceramic dielectric filter, a frequency response curve can be obtained, in which at least one desired transmission zero is generated on the left side and the right side of the filter passband to enhance the suppression degree of the band adjacent to the passband, thereby realizing and improving the frequency selectivity of the ceramic dielectric filter, so that the ceramic dielectric filter has the advantages of simple structure, easy implementation, and superior frequency selectivity. Additionally, each first resonator unit 100 and each second resonator unit 200 may be welded in sequence according to a predetermined topology, or may be machined and polished from an integral dielectric, so as to form the above-mentioned ceramic dielectric filter.

In addition, the depth of the first tuning blind hole 101 and the depth of the second tuning blind hole 102 can be reasonably distributed as required to adjust the coupling amount between the first resonance unit 100 and each second resonance unit 200 adjacent to the first resonance unit 100. Specifically, on the basis of ensuring that the total capacitance loading is constant, that is, on the basis of ensuring that the resonant frequency of the first resonant unit 100 is not changed, the ratio of the depth of the first tuning blind hole 101 to the depth of the second tuning blind hole 102 can be appropriately adjusted to flexibly adjust the coupling amount between the first resonant unit 100 and each second resonant unit 200. For example, as shown in fig. 1, by increasing the depth of the first tuning blind via 101, the coupling amount between the first resonant unit 100 and the adjacent second resonant unit 200 at the upper side thereof can be reduced, i.e. the capacitive coupling is reduced, and accordingly, to ensure that the total capacitance loading amount is not changed, the depth of the second tuning blind via 102 is correspondingly reduced, so that the coupling amount between the first resonant unit 100 and the adjacent second resonant unit 200 at the right side and the upper right corner thereof is increased, i.e. the inductive coupling is increased; conversely, by reducing the depth of the first tuning blind hole 101, the coupling amount between the first resonant unit 100 and the adjacent second resonant unit 200 at the upper side thereof can be increased, i.e. the capacitive coupling is increased, and accordingly, to ensure that the total capacitance loading amount is not changed, the depth of the second tuning blind hole 102 needs to be correspondingly increased, so that the coupling amount between the first resonant unit 100 and the adjacent second resonant unit 200 at the right side and the upper right corner thereof is reduced, i.e. the inductive coupling is reduced.

The ceramic dielectric filter provided by the embodiment of the application has the technical effects that: according to the application, the first resonant unit 100 is provided with the first tuning blind hole 101 and the second tuning blind hole 102 which are arranged at intervals, the second resonant unit 200 is provided with the third tuning blind hole 201, the first resonant unit 100 can work in a loaded TE102 mode by adjusting the depth of the first tuning blind hole 101 and the depth of the second tuning blind hole 102, and the second resonant unit 200 can work in a loaded TE101 mode by adjusting the depth of the third tuning blind hole 201, so that the first resonant unit 100 can be mutually coupled with the adjacent second resonant unit 200 to generate capacitive coupling and inductive coupling, and a required transmission zero point is generated near a filter passband frequency band, thereby improving the frequency selection performance of the ceramic dielectric filter. The ceramic dielectric filter provided by the embodiment of the application can realize capacitive coupling without arranging additional accessories or structural features on the resonance unit, has a simple structure, is easy to realize, and has better frequency selection performance.

Referring to fig. 1-3, in the embodiment of the present application, a first tuning blind hole 101 is disposed between the center of the side surface of the first opening and the connection point of the first opening and the side surface of the second opening; a second tuning blind hole 102 is arranged between the center of the side surface of the first opening and the joint of the center and one of the other side surfaces of the second opening.

In this embodiment, the first tuning blind hole 101 is disposed between the center of the side surface of the first opening and the joint of the side surface of the first opening and the side surface of one second opening, that is, the first tuning blind hole 101 is disposed near one second resonance unit 200 disposed adjacent to the first resonance unit 100, so that the coupling degree of the electromagnetic field exposed between the first resonance unit 100 and the second resonance unit 200 can be ensured, thereby ensuring the coupling relationship between the first resonance unit 100 and the second resonance unit 200; similarly, the second tuning blind hole 102 is disposed between the center of the side of the first opening and the joint of the side of the first opening and the side of the other second opening, that is, the second tuning blind hole 102 is disposed near the other second resonance unit 200 disposed adjacent to the first resonance unit 100, so that the coupling degree of the electromagnetic field exposed to each other between the first resonance unit 100 and the second resonance unit 200 can be ensured, thereby ensuring the coupling relationship between the first resonance unit 100 and the other second resonance unit 200. By combining the arrangement, the capacitive coupling and the inductive coupling strength of the ceramic dielectric filter are ensured, so that the frequency selection characteristic of the ceramic dielectric filter is ensured.

Referring to fig. 1 to 3, in the embodiment of the present application, the thicknesses of the first resonant unit 100 and the second resonant unit 200 are equal.

The thicknesses of the first resonance units 100 and the second resonance units 200 are all set to be equal, on one hand, after the first resonance units 100 and the second resonance units 200 are connected and arranged to form the ceramic dielectric filter, the top surface of the ceramic dielectric filter is ensured to be flush, that is, the ceramic dielectric filter is ensured to have a determined height, so that the optimized layout and thinning design of the ceramic dielectric filter are facilitated, and the miniaturization design is facilitated; on the other hand, the cascade direction between each first resonance unit 100 and each second resonance unit 200 can be ensured to be in a substantially horizontal direction, so that the coupling amount between each first resonance unit 100 and each second resonance unit 200 can be accurately controlled.

Referring to fig. 1 to 3, in the embodiment of the present application, a cross-sectional area of the first resonant unit 100 on a side perpendicular to the first opening is greater than or equal to a cross-sectional area of the second resonant unit 200 on a side perpendicular to the second opening.

When the depths of the first tuning blind hole 101 and the second tuning blind hole 102 are enough to enable the first resonance unit 100 to work in the TE102 mode, the cross-sectional dimension of the first resonance unit 100 is set to be equivalent to the cross-sectional dimension of the second resonance unit 200, so that on one hand, the increase of the overall dimension of the ceramic dielectric filter can be avoided, the miniaturization development of the ceramic dielectric filter is facilitated, and the application range of the ceramic dielectric filter can be expanded to a certain extent; on the other hand, it is also beneficial to optimally design the connection arrangement of each first resonance unit 100 and each second resonance unit 200. On one hand, the sectional size of the first resonance unit 100 is larger than that of the second resonance unit 200, so that the planar size occupied by the first resonance unit 100 can be adjusted to be directly coupled with the plurality of second resonance units 200, thereby ensuring the coupling amount between the first resonance unit 100 and the plurality of second resonance units 200; on the other hand, the first tuning blind hole 101 and the second tuning blind hole 102 can be arranged to jointly enable the first resonant unit 100 to operate in the TE102 mode, so that the depths required by the first tuning blind hole 101 and the second tuning blind hole 102 can be reduced to a certain extent while avoiding the increase of the overall size of the ceramic dielectric filter.

Referring to fig. 1 to 3, in the embodiment of the present application, each first resonant unit 100 and each second resonant unit 200 are arranged in an array having at least two rows.

In order to make the first resonant unit 100 and the two second resonant units 200 respectively perform capacitive coupling and inductive coupling, and facilitate the development of the ceramic dielectric filter toward miniaturization, light weight and integration, in the embodiment, each first resonant unit 100 and each second resonant unit 200 are connected and arranged in an array with at least two rows, so as to reduce the overall size of the ceramic dielectric filter to a certain extent. In addition, in the present embodiment, the first resonant units 100 and the second resonant units 200 are arranged in a staggered manner, so that the distance between each first resonant unit 100 and each second resonant unit 200 can be shortened to a certain extent, and the coupling amount between the first resonant unit 100 and each second resonant unit 200 adjacent thereto can be enhanced to a certain extent, so that the balance of the transmission zeros on the left and right sides of the filter passband can be adjusted. For example, as shown in fig. 1, the ceramic dielectric filter arranges each first resonance unit 100 and each second resonance unit 200 in two rows, and each second resonance unit 200 in the upper row is positioned between the adjacent first resonance unit 100 and second resonance unit 200 in the lower row in a crossed manner, or between two adjacent second resonance units 200. Therefore, the first resonant unit 100 at the lower left corner can be directly coupled with the second resonant unit 200 at the upper left corner, the second resonant unit 200 at the upper right corner and the second resonant unit 200 at the right side, so that the mutual coupling amount can be ensured and enhanced, and the frequency selection performance of the ceramic dielectric filter is improved. And, by enhancing the inductive coupling strength of the first resonance unit 100 at the lower left corner and the second resonance unit 200 at the upper right corner thereof, the degree of balance between the transmission zero points located at the left side and the right side of the filter passband can be adjusted, specifically, the stronger the inductive coupling of the first resonance unit 100 at the lower left corner and the second resonance unit 200 at the upper right corner thereof, the closer the transmission zero point located at the left side of the filter passband will be to the frequency passband, and the farther the transmission zero point located at the right side of the filter passband will be from the frequency passband, so as to satisfy the requirement of higher suppression degree at the left side of the passband.

Referring to fig. 1 to 3, in the embodiment of the present application, each first resonant unit 100 and each second resonant unit 200 are integrally formed. Based on the arrangement, on one hand, the production convenience of the ceramic dielectric filter can be improved to a certain extent, namely, the production efficiency of the ceramic dielectric filter is improved, and the ceramic dielectric filter is beneficial to batch production; on the other hand, the processing error between each first resonance unit 100 and each second resonance unit 200 can be reduced, so that the position accuracy between each first resonance unit 100 and each second resonance unit 200 is guaranteed, the accurate control of the coupling amount between each first resonance unit 100 and each second resonance unit 200 is facilitated, and the manufacturing accuracy of the ceramic dielectric filter is guaranteed.

Referring to fig. 1 to 3, in the embodiment of the present application, at least one first separating through groove 301 is formed at a joint of a side surface of the first opening and a side surface of the second opening of the ceramic dielectric filter, and the first separating through groove 301 can be used for separating the first resonant unit 100 from the second resonant unit 200, so that the first resonant unit 100 and the second resonant unit 200 are not coupled at the first separating through groove 301; at least one second separating through groove 302 is formed at the joint of the two second open side surfaces of the ceramic dielectric filter, and the second separating through groove 302 can be used for separating the two second resonant units 200, so that the two second resonant units 200 are not coupled at the second separating through groove 302.

Based on the arrangement in which each first resonance unit 100 and each second resonance unit 200 are integrally formed, in the present embodiment, a first separating through groove 301 is formed between the first resonance unit 100 and the second resonance unit 200 that are coupled with each other, so that the first resonance unit 100 and the second resonance unit 200 are disconnected from each other at the position where the first separating through groove 301 is formed, that is, in the region where the first separating through groove 301 is disconnected, the first resonance unit 100 and the second resonance unit 200 will not be coupled, but in the portion where the first resonance unit 100 and the second resonance unit 200 are connected, the first resonance unit 100 and the second resonance unit 200 will be coupled, and thus, the control of the amount of coupling between the first resonance unit 100 and the second resonance unit 200 can be achieved by adjusting the position, size, and shape of the first separating through groove 301. Similarly, the second separating through groove 302 is formed between the two second resonant units 200 coupled to each other, so that the two second resonant units 200 are disconnected at the position where the second separating through groove 302 is formed, that is, the two second resonant units 200 will not be coupled in the region where the second separating through groove 302 is disconnected, but will be coupled at the portion where the two second resonant units 200 are connected, and thus, the control of the coupling amount between the two second resonant units 200 can be realized by adjusting the position, size and shape of the second separating through groove 302.

Referring to fig. 1-3, in the present embodiment, the first tuning blind hole 101 has a circular cross-sectional shape. The cross section of the first tuning blind hole 101 is arranged in a circular shape, so that on one hand, the processing convenience of the first tuning blind hole 101 can be improved, and the processing precision of the first tuning blind hole 101 is easily guaranteed; on the other hand, the equalization of the electromagnetic field formed by the first resonance unit 100 near the first tuning blind hole 101 can be ensured, thereby being beneficial to ensuring the average strength of the capacitive coupling or the inductive coupling between the first resonance unit 100 and the second resonance unit 200 and being beneficial to realizing the accurate control of the coupling amount between the first resonance unit 100 and the second resonance unit 200.

Referring to fig. 1-3, in the present embodiment, the second tuning blind hole 102 has a circular cross-sectional shape. The cross section of the second tuning blind hole 102 is circular, so that on one hand, the processing convenience of the second tuning blind hole 102 can be improved, and the processing precision of the second tuning blind hole 102 is easily guaranteed; on the other hand, the equalization of the electromagnetic field formed by the first resonance unit 100 near the second tuning blind hole 102 can be ensured, thereby being beneficial to ensuring the average strength of the capacitive coupling or the inductive coupling between the first resonance unit 100 and the second resonance unit 200 and being beneficial to realizing the accurate control of the coupling amount between the first resonance unit 100 and the second resonance unit 200.

Referring to fig. 1 to 3, in the embodiment of the present application, the first resonant unit 100 includes a first resonant cavity made of a ceramic material and a first metal cavity wall made of a metal material, the first metal cavity wall is wrapped on an outer surface of the first resonant cavity; the second resonant unit 200 includes a second resonant cavity made of a ceramic material and a second metal cavity wall made of a metal material, and the second metal cavity wall is wrapped on an outer surface of the second resonant cavity.

In this embodiment, the first resonant unit 100 includes a first resonant cavity and a first metal cavity wall, and the second resonant unit 200 includes a second resonant cavity and a second metal cavity wall, wherein the first resonant cavity and the second resonant cavity are both made of a ceramic material, i.e., an electrically insulating material, and the first metal cavity wall and the second metal cavity wall are made of a metal material, i.e., an electrically conductive material. Based on the above arrangement, the electromagnetic field of the adjacent first resonance unit 100 and the electromagnetic field of the second resonance unit 200 can be exposed to each other in the ceramic dielectric to directly generate capacitive coupling and inductive coupling, so that the frequency selection performance of the ceramic dielectric filter can be improved. In addition, the insertion loss of the ceramic dielectric filter can be reduced to a certain extent by arranging the first metal cavity wall and the second metal cavity wall.

In an embodiment of the application, the first metal cavity wall is a first metal cavity wall made of copper or silver. In this embodiment, the first metal cavity wall is made of copper or silver with higher conductivity, so that the insertion loss of the ceramic dielectric filter can be further reduced.

In an embodiment of the application, the second metal cavity wall is a second metal cavity wall made of copper or silver. In this embodiment, the second metal cavity wall is made of copper or silver with higher conductivity, so that the insertion loss of the ceramic dielectric filter can be further reduced.

Referring to fig. 1 to 3, in the embodiment of the present application, there are two first resonant units 100, seven second resonant units 200, the two first resonant units 100 are spaced apart, and any one first resonant unit 100 is capacitively coupled to one second resonant unit 200 and is inductively coupled to the two second resonant units 200.

The topology of the ceramic dielectric filter described above is designed as shown in fig. 3. Specifically, at the initial stage of design, the topological structure of the ceramic dielectric filter is designed according to the requirements of the communication system, that is, the connection arrangement manner between each first resonant unit 100 and each second resonant unit 200 is designed, and the feasibility of the topological structure is verified through circuit simulation software.

As shown in fig. 1, based on the above topology, five second resonant units 200 are sequentially and adjacently arranged in a row, and the other two second resonant units 200 are arranged at the lower sides of the three second resonant units 200 in the middle of the upper row and are respectively arranged between every two second resonant units 200 in a staggered manner, and the two first resonant units 100 are respectively arranged at two sides of the two second resonant units 200 in the lower row, so that the arrangement can not only ensure the connection arrangement manner between each first resonant unit 100 and each second resonant unit 200, but also maximally utilize the space, so that the ceramic dielectric filter can tend to develop towards the direction of miniaturization, light weight and integration.

In this embodiment, the third resonant unit 200 in the upper row is used as a boundary, the ceramic dielectric filter is divided into two groups of cross-coupled devices, and each group of cross-coupled devices includes a first resonant unit 100 operating in the TE102 mode. In the cross-coupling module on the left side, the first resonance unit 100 on the lower left corner is capacitively coupled to the second resonance unit 200 on the upper side thereof and inductively coupled to the two second resonance units 200 on the upper right side and the right side thereof, the remaining two adjacent second resonance units 200 are inductively coupled to each other, and in the cross-coupling module on the right side, the first resonance unit 100 on the lower right corner is capacitively coupled to the second resonance unit 200 on the upper side thereof and inductively coupled to the two second resonance units 200 on the upper left side and the left side thereof, and the remaining two adjacent second resonance units 200 are inductively coupled to each other, so that the desired frequency response characteristic is realized. Additionally, in this embodiment, the length of each first resonance unit 100 is slightly greater than the length of each second resonance unit 200, the first resonance unit 100 at the lower left corner is directly coupled with the second resonance unit 200 at the upper side thereof, the second resonance unit 200 at the upper right corner and the second resonance unit 200 at the right side, and the first resonance unit 100 at the lower right corner is directly coupled with the second resonance unit 200 at the upper side thereof, the second resonance unit 200 at the upper left corner and the second resonance unit 200 at the left side thereof, so as to facilitate ensuring and enhancing the coupling amount therebetween, and improve the frequency selection performance of the ceramic dielectric filter.

As shown in fig. 4, in the frequency response curve of the ceramic dielectric filter, each group of cross-coupling components generates a required transmission zero on the left side and the right side of the filter passband, that is, the ceramic dielectric filter generates two transmission zeros on both sides of the filter passband frequency band, and the transmission zeros can enhance the suppression degree of the passband adjacent frequency band, thereby improving the frequency selectivity of the ceramic dielectric filter to a certain extent. Additionally, by enhancing the inductive coupling strength between the first resonance unit 100 at the lower left corner and the second resonance unit 200 at the upper right corner thereof, the degree of balance between the transmission zero point at the left side of the filter passband and the transmission zero point at the right side generated by the cross-coupling component at the left side can be correspondingly adjusted, specifically, the stronger the inductive coupling between the first resonance unit 100 at the lower left corner and the second resonance unit 200 at the upper right corner thereof, the closer the transmission zero point at the left side of the filter passband will be to the frequency passband, and the farther the transmission zero point at the right side of the filter passband will be from the frequency passband, so that the requirement of higher suppression degree at the left side of the passband can be satisfied; similarly, by enhancing the inductive coupling strength between the first resonant unit 100 at the lower right corner and the second resonant unit 200 at the upper left corner, the balance between the transmission zero at the left side of the filter passband and the transmission zero at the right side generated by the cross-coupling component at the right side can be adjusted, specifically, the stronger the inductive coupling between the first resonant unit 100 at the lower right corner and the second resonant unit 200 at the upper left corner, the closer the transmission zero at the left side of the filter passband will be to the frequency passband, and the farther the transmission zero at the right side of the filter passband will be from the frequency passband, so as to satisfy the requirement of higher suppression degree at the left side of the passband.

Referring to fig. 1-3, in the embodiment of the present application, each first resonant unit 100 has a third opening side surface opposite to the first opening side surface, each second resonant unit 200 has a fourth opening side surface opposite to the second opening side surface, the ceramic dielectric filter has a signal access port 303 disposed on one of the third opening side surface and the fourth opening side surface, and a signal feed-out port 304 disposed on one of the remaining third opening side surface and the fourth opening side surface, the signal access port 303 is used for inputting a signal, and the signal feed-out port 304 is used for feeding out a signal.

After each first resonance unit 100 and each second resonance unit 200 are assembled, based on the topology of each first resonance unit 100 and each second resonance unit 200, a signal input port is required to be provided on the third opening side or the fourth opening side connected to the head ends of each first resonance unit 100 and each second resonance unit 200, a signal feed-out port 304 is disposed on a third opening side or a fourth opening side which is connected to and arranged at the tail end of each of the first resonance unit 100 and the second resonance unit 200, through the arrangement of the signal access port 303 and the signal feed-out port 304, electromagnetic energy can be input from the signal access port 303, interference signals and clutter signals in specific frequencies are filtered through the first resonance units 100 and the second resonance units 200 which are coupled in sequence, and finally signals in required frequencies are fed out from the signal output port. That is, the testing and use of the ceramic dielectric filter will be facilitated by the arrangement of the signal access port 303 and the signal feed-out port 304.

For example, as shown in fig. 1, the third resonant unit 200 in the upper row is connected to the resonant units arranged at the head ends of the first resonant unit 100 and the second resonant unit 200, and thus, a signal input port is required to be provided at the fourth opening side thereof for inputting electromagnetic energy into the ceramic dielectric filter, and the fourth resonant unit 200 in the upper row is connected to the resonant units arranged at the tail ends of the first resonant unit 100 and the second resonant unit 200, and thus, a signal feed-out port 304 is required to be provided at the fourth opening side thereof for feeding out signals in a desired frequency from the ceramic dielectric filter. Further, there is no coupling relationship between the third second resonant cell 200 in the upper row and the fourth second resonant cell 200 in the upper row, and thus a second separating channel 302 may be opened between the third second resonant cell 200 in the upper row and the fourth second resonant cell 200 in the upper row to substantially completely separate the connection relationship therebetween, so that no coupling occurs between the third second resonant cell 200 in the upper row and the fourth second resonant cell 200 in the upper row.

Example two

The difference between this embodiment and the first embodiment is:

referring to fig. 5 to 7, in the embodiment of the present invention, there are one first resonant unit 100 and seven second resonant units 200, and the first resonant unit 100 is capacitively coupled to one second resonant unit 200 and is inductively coupled to two second resonant units 200.

The topology of the ceramic dielectric filter described above is designed as shown in fig. 7. Specifically, at the initial stage of design, the topological structure of the ceramic dielectric filter is designed according to the requirements of the communication system, that is, the connection arrangement manner between the first resonant unit 100 and each second resonant unit 200 is designed, and the feasibility of the topological structure is verified through circuit simulation software.

As shown in fig. 5, based on the above topology, four second resonant units 200 are sequentially arranged adjacently to form a row, and the remaining three second resonant units 200 and one first resonant unit 100 are sequentially arranged adjacently to form a row, wherein the size of the first resonant unit 100 is equivalent to the size of each second resonant unit 200, and the four second resonant units 200 in the upper row are arranged in one-to-one up-and-down alignment with the three second resonant units 200 in the lower row and one first resonant unit 100, so that not only the connection arrangement between each first resonant unit 100 and each second resonant unit 200 can be ensured, but also the overall size of the ceramic dielectric filter can be maximally compressed, so that the ceramic dielectric filter can tend to be developed in the direction of miniaturization, light weight and integration.

In this embodiment, the first resonant unit 100 is capacitively coupled to the second resonant unit 200 on the upper side thereof, and is inductively coupled to the second resonant units 200 on the left side and the upper left side thereof, and the other two adjacent second resonant units 200 are inductively coupled to each other, so as to achieve the desired frequency response characteristic, thereby improving the frequency selectivity of the ceramic dielectric filter.

As shown in fig. 8, in the frequency response curve of the ceramic dielectric filter, a desired transmission zero is generated on each of the left side and the right side of the filter passband, and the rejection of the band adjacent to the passband can be enhanced by the transmission zero, so that the frequency selectivity of the ceramic dielectric filter can be improved to a certain extent. Additionally, by enhancing the inductive coupling strength between the first resonance unit 100 at the lower right corner and the second resonance unit 200 at the upper left corner, the degree of balance between the transmission zero points at the left side and the right side of the filter passband generated by the inductive coupling strength can be adjusted, specifically, the stronger the inductive coupling between the first resonance unit 100 at the lower right corner and the second resonance unit 200 at the upper left corner, the closer the transmission zero point at the left side of the filter passband is to the frequency passband, and the farther the transmission zero point at the right side of the filter passband is from the frequency passband, so as to satisfy the requirement of higher suppression degree at the left side of the passband.

As shown in fig. 6, after the first resonator unit 100 and each of the second resonator units 200 are assembled, based on the topology of the first resonance unit 100 and each second resonance unit 200, a signal input port is required to be disposed on the third opening side or the fourth opening side which is connected to the head ends of the first resonance unit 100 and each second resonance unit 200, a signal feed-out port 304 is disposed on a third opening side or a fourth opening side which is connected to and arranged at the tail ends of the first resonance unit 100 and each of the second resonance units 200, through the arrangement of the signal access port 303 and the signal feed-out port 304, electromagnetic energy can be input from the signal access port 303, interference signals and clutter signals in specific frequencies are filtered through the first resonance unit 100 and each second resonance unit 200 which are coupled in sequence, and finally signals in required frequencies are fed out from the signal output port. That is, the testing and use of the ceramic dielectric filter will be facilitated by the arrangement of the signal access port 303 and the signal feed-out port 304.

As shown in fig. 5, the second resonant unit 200 of the upper row is connected to the resonant unit arranged at the head end of the first resonant unit 100 and each second resonant unit 200, and thus, a signal input port is provided at the fourth opening side thereof for inputting electromagnetic energy into the ceramic dielectric filter, and the third resonant unit 200 of the upper row is connected to the resonant unit arranged at the tail end of the first resonant unit 100 and each second resonant unit 200, and thus, a signal feed-out port 304 is provided at the fourth opening side thereof for feeding out a signal in a desired frequency from the ceramic dielectric filter. Further, there is no coupling relationship between the second resonance unit 200 in the upper row and the third resonance unit 200 in the upper row, and thus a second separating channel 302 may be formed between the second resonance unit 200 in the upper row and the third resonance unit 200 in the upper row to substantially completely separate the connection relationship therebetween, so that the second resonance unit 200 in the upper row and the third resonance unit 200 in the upper row are not coupled.

The present invention is not intended to be limited to the particular embodiments shown and described, but is to be accorded the widest scope consistent with the principles and novel features herein disclosed.

Claims

1. A ceramic dielectric filter is characterized by comprising at least one first resonant unit and at least two second resonant units, wherein each first resonant unit is provided with a first open pore side, a first tuning blind hole and a second tuning blind hole are formed in the first open pore side at a distance, each second resonant unit is provided with a second open pore side which is parallel to and faces the first open pore side and faces the same direction, a third tuning blind hole is formed in the second open pore side, the depth of the first tuning blind hole and the depth of the second tuning blind hole are both larger than the depth of the third tuning blind hole, the working mode of the first resonant unit is TE102 mode, the working mode of the second resonant unit is TE101 mode, and any first resonant unit is at least capacitively coupled with one second resonant unit, and is inductively coupled with at least one of the second resonance units, and any one of the second resonance units is inductively coupled with at least one of the other second resonance units.

2. A ceramic dielectric filter as claimed in claim 1 wherein said first tuning blind hole is located between the center of said first open side and the junction with said second open side; and the second tuning blind hole is arranged between the center of the side surface of the first opening and the joint of the center of the side surface of the first opening and one of the other side surfaces of the second opening.

3. A ceramic dielectric filter as claimed in claim 1, wherein the thickness of each of said first resonator element and said second resonator element is equally set.

4. A ceramic dielectric filter as claimed in claim 3 wherein the cross-sectional area of said first resonator element on a side perpendicular to said first opening is greater than or equal to the cross-sectional area of said second resonator element on a side perpendicular to said second opening.

5. A ceramic dielectric filter as claimed in claim 3 wherein each of said first resonator elements and each of said second resonator elements are arranged in an array having at least two rows.

6. A ceramic dielectric filter as claimed in claim 1, wherein each of said first resonator elements and each of said second resonator elements are integrally formed.

7. The ceramic dielectric filter of claim 6, wherein the ceramic dielectric filter defines at least a first separating channel at a junction between the first opening side and the second opening side, the first separating channel being capable of separating the first resonator element from the second resonator element such that the first resonator element and the second resonator element are not coupled at the first separating channel;

8. A ceramic dielectric filter as claimed in claim 1 wherein said first tuning blind hole is circular in cross-sectional shape.

9. A ceramic dielectric filter as claimed in claim 1 wherein said second tuning blind hole is circular in cross-sectional shape.

10. A ceramic dielectric filter as claimed in claim 1 wherein the first resonator element comprises a first resonator cavity formed of a ceramic material and a first metal cavity wall formed of a metal material, the first metal cavity wall being clad around an outer surface of the first resonator cavity;

11. A ceramic dielectric filter as claimed in claim 10 wherein the first metal cavity walls are first metal cavity walls made of copper or silver.

12. A ceramic dielectric filter as claimed in claim 10 wherein the second metal cavity walls are second metal cavity walls made of copper or silver.

13. A ceramic dielectric filter as claimed in claim 1 wherein there are two of said first resonant cells and seven of said second resonant cells, said first resonant cells being spaced apart, any one of said first resonant cells being capacitively coupled to one of said second resonant cells and being inductively coupled to both of said second resonant cells.

14. A ceramic dielectric filter as claimed in claim 1, wherein there is one of said first resonator elements and seven of said second resonator elements, said first resonator element being capacitively coupled to one of said second resonator elements and being inductively coupled to both of said second resonator elements.

15. The ceramic dielectric filter of claim 1, wherein each of the first resonator elements has a third opening side surface facing opposite to the first opening side surface, each of the second resonator elements has a fourth opening side surface facing opposite to the second opening side surface, the ceramic dielectric filter has a signal access port opened on one of the third opening side surfaces and the fourth opening side surfaces, and a signal feed-out port opened on one of the remaining third opening side surfaces and the fourth opening side surfaces, the signal access port being for an input signal and the signal feed-out port being for a feed-out signal.