CN111146534B

CN111146534B - A dielectric filter and a communication device

Info

Publication number: CN111146534B
Application number: CN202010042514.9A
Authority: CN
Inventors: 吴文敬; 李�杰; 吴亚晖; 王浩
Original assignee: Shenzhen Tatfook Technology Co Ltd
Current assignee: Shenzhen Tatfook Technology Co Ltd
Priority date: 2020-01-15
Filing date: 2020-01-15
Publication date: 2025-04-15
Anticipated expiration: 2040-01-15
Also published as: CN111146534A

Abstract

The present invention provides a dielectric filter and a communication device, comprising at least three dielectric resonators connected to each other, each dielectric resonator comprising a body made of solid dielectric material and a tuning hole located on the surface of the body, the bodies of all dielectric resonators constitute the body of the dielectric filter, the surface of the body of the dielectric filter and the surface of the tuning hole are covered with a conductive layer, two electrodes are respectively arranged on the surfaces of two dielectric resonators located on one side of the input and output ports, a transmission line is arranged on a carrier, and when the carrier is fixed on the dielectric resonator, the transmission line is suitable for connecting the two electrodes and transmitting electrical signals. The two electrodes are arranged on the surface of the resonator, and the transmission line connecting the electrodes is arranged on an external carrier, and the two electrodes are connected by connecting the external carrier with the resonator body, the structure is simple, easy to adjust, and convenient to realize negative cross coupling.

Description

Dielectric filter and communication device

Technical Field

The invention relates to the technical field of communication, in particular to a dielectric filter and a communication device.

Background

5G communication is the most advanced communication technology at present, and various communication companies compete for research on related aspects. The Sub 6GHz adopts the MIMO technology, so a large number of filters are required to be integrated inside the antenna, and thus, the size and weight of the filters are required to be higher. The conventional metal filter cannot be integrated with an antenna due to its large volume and weight.

The size and weight of the miniaturized dielectric filter realized by adopting the high-dielectric constant material are lower than 1/100 of those of the traditional filter, so that the miniaturized dielectric filter is an effective solving way for realizing a Sub 6GHz MIMO communication system at present. The dielectric filter is formed by adopting a body made of solid dielectric materials (such as ceramic materials with high dielectric constants) and metallizing (such as silver plating) the surface of the body to form dielectric resonators, and forming the dielectric filter through a plurality of dielectric resonators connected in sequence and coupling among the resonators (including direct coupling among adjacent dielectric resonators and cross coupling among non-adjacent dielectric resonators). Wherein the coupling between the individual resonators can be classified into positive coupling (which may also be referred to as inductive coupling) and negative coupling (which may also be referred to as capacitive coupling) according to the polarity. The cross coupling with positive polarity is easy to realize, but the cross coupling with negative polarity is difficult to realize.

In order to realize negative cross coupling of the dielectric filter, a flying rod with a metalized surface is adopted in the prior art to connect two dielectric resonators, and the existing flying rod material and form are mainly made of metal materials and are matched with a flying rod seat to be installed in a cavity for use. The installation through machining is complicated in process, cannot be adjusted after installation, is inconvenient to debug, and needs to disassemble the metal cover plate, take out the flying rod, change the length or the shape of the flying rod in a machining mode, and then fill the cavity for testing, so that one-time debugging is completed. However, repeated machining and performance test operations seriously affect the performance of the filter, and the debugging is complex and the production efficiency is low.

Disclosure of Invention

Therefore, the invention aims to solve the technical problems that the dielectric filter in the prior art adopts a dielectric fly rod, is complex to process, cannot be adjusted after being installed, is complex to debug and has low production efficiency.

To this end, the invention proposes a dielectric filter comprising:

The dielectric resonator comprises at least three connected dielectric resonators, wherein each dielectric resonator comprises a body made of solid dielectric materials and tuning holes positioned on the surface of the body, the bodies of all the dielectric resonators form the body of the dielectric filter, the surfaces of the body of the dielectric filter and the surfaces of the tuning holes are covered with conductive layers, and the dielectric resonator is characterized in that:

The two electrodes are respectively arranged on the surfaces of the two dielectric resonators positioned at one side of the input/output port;

and the transmission line is arranged on the carrier and is suitable for connecting the two electrodes when the carrier is fixed on the dielectric resonator.

Any one of the electrodes is formed on the surface of the dielectric resonator by the conductive layer.

The electrodes are round, square or triangular.

The depth of the tuning hole, the area of the conductive layer covered in the tuning hole and the position of the conductive layer in the tuning hole are related to the resonant frequency of the dielectric resonator where the tuning hole is located.

The thickness of the conductive layer is greater than or equal to the skin depth.

The conductive layer is a silver layer.

The carrier is a PCB.

The transmission line is a copper layer, a silver-plated line or a silver-plated transmission rod of the PCB.

The solid dielectric material is a ceramic material.

All dielectric resonator bodies are integrally formed from the same solid dielectric material.

The invention provides a communication device comprising at least one dielectric filter as described above.

The technical scheme of the invention has the following advantages:

1. The invention provides a dielectric filter, at least three connected dielectric resonators, each dielectric resonator comprises a body formed by solid dielectric materials and a tuning hole positioned on the surface of the body, the bodies of all dielectric resonators form the body of the dielectric filter, the surfaces of the body and the tuning hole of the dielectric filter are covered with conducting layers, two electrodes are respectively arranged on the surfaces of the two dielectric resonators positioned on one side of an input port and an output port, a transmission line is arranged on a carrier, and the transmission line is suitable for connecting the two electrodes and transmitting electric signals when the carrier is fixed on the dielectric resonators. The two electrodes are arranged on the surface of the resonator, the transmission line for connecting the electrodes is arranged on the external carrier, and the two electrodes are connected through the connection between the external carrier and the resonator body, so that the structure is simple, the adjustment is easy, and the negative cross coupling is convenient to realize.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of a dielectric filter according to the present invention;

FIG. 2 is a schematic diagram of a tuning hole structure in a dielectric filter according to the present invention;

fig. 3 is a frequency response curve of a dielectric filter according to the present invention.

Reference numerals illustrate:

1-ceramic body, 11-silver layer, 2-electrode, 3-input/output port, 4-tuning hole, 5-transmission line, 6-PCB, 61-grounding copper layer, 62-PCB through hole, 63-abdication hole and 7-green oil.

Detailed Description

The following description of the embodiments of the present invention will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the invention are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, unless explicitly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected, mechanically connected, electrically connected, directly connected, indirectly connected via an intervening medium, or in communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.

In addition, the technical features of the different embodiments of the present invention described below may be combined with each other as long as they do not collide with each other.

Example 1

The present embodiment provides a dielectric filter, including at least three connected dielectric resonators, each dielectric resonator including a body made of a solid dielectric material and a tuning hole 4 located on a surface of the body, and the bodies of all the dielectric resonators constitute a body of the dielectric filter. In this embodiment, as shown in fig. 1, four dielectric resonators are provided, each dielectric resonator has a tuning hole 4, the four dielectric resonators are arranged in a letter-ji shape, and five, six, etc. dielectric resonators may be provided. In this embodiment, the solid dielectric material is a ceramic material, and the body of the dielectric resonator is the ceramic body 1, although other materials may be used as needed. In this embodiment, all the dielectric resonator bodies are integrally formed by the same ceramic body 1, as shown in fig. 2, that is, four tuning holes 4 are formed in a field-shaped distribution on the same ceramic body 1.

The surface of the ceramic body 1 is covered with a conductive layer, and the conductive layer can be a metal layer such as a copper layer, a tin layer, a silver layer 11 or an aluminum layer, and the thickness of the conductive layer is larger than or equal to the skin depth. In this embodiment, the conductive layer is a silver layer 11, which covers the surface of the ceramic body 1, so as to realize a completely enclosed electromagnetic field transmission structure. The tuning hole 4 is covered with a silver layer 11, and the depth of the tuning hole 4 and the area of the silver layer 11 covered in the tuning hole 4 and the position of the silver layer 11 in the tuning hole 4 are related to the resonant frequency of the dielectric resonator in which the tuning hole 4 is located, for example, the silver layer 11 is annularly distributed on the bottom of the tuning hole 4 or is strip-shaped distributed on the inner wall of the tuning hole 4, etc.

On the surface of one side of the ceramic body 1 opposite to the tuning hole 4, a closed ring-shaped silver layer 11 is partially removed by removing material, the silver layer 11 remained in the middle forms an electrode 2, the silver layer 11 is also removed around the periphery of the two input and output ports 3, and green oil 7 is coated on the removed part. As shown in fig. 1, in this embodiment, the ring-shaped silver layer 11 is removed, so that the electrode 2 with the size of the inner circle of the ring is obtained, and of course, the electrode 2 obtained by removing the silver layer 11 may also have a square shape or a triangle shape, as required.

The transmission line 5 may be a copper layer of a PCB, a silver-plated line or a silver-plated transmission rod, etc. which can transmit an electrical signal, the transmission line 5 is disposed on a carrier, in this embodiment, the transmission line 5 adopts the copper layer of the PCB, the carrier is the PCB6, the copper layer is disposed on the PCB6, as shown in fig. 1, the surface of the PCB6 is covered with the copper layer, a dumbbell-shaped copper layer transmission line is formed by removing the copper layer, a removed portion is coated with green oil 7, a plurality of PCB through holes 62 are formed on the periphery of the removed portion, so as to play roles of shielding and grounding, a grounding copper layer 61 is formed on the copper layer of the rest, and a hole 63 corresponding to an input/output port is also formed on the PCB 6. The PCB6 is welded on the surface of the ceramic body 1 by soldering tin, and a gap of 0.2mm-0.4mm is reserved between the PCB6 and the ceramic body 1. The two ends of the transmission line 5 are welded with the silver layers 11 of the two electrodes 2 by soldering, so that the transmission of an electric field is realized. Of course, the carrier may also be air (i.e. the two electrodes are directly connected to the ceramic body by a copper layer or silver plated wire, etc.), ceramic, or the like, as desired. Fig. 3 is a frequency response curve of the dielectric filter in the present embodiment.

The two electrodes 2 are arranged on the surface of the resonator, and the transmission line 5 for connecting the electrodes 2 is arranged on the external carrier, so that the two electrodes 2 are connected through the connection of the external carrier and the resonator body, the structure is simple, the adjustment is easy, and the negative cross coupling is convenient to realize.

Example 2

The present embodiment provides a communication device including at least one of the dielectric filters of embodiment 1.

It is apparent that the above examples are given by way of illustration only and are not limiting of the embodiments. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. While still being apparent from variations or modifications that may be made by those skilled in the art are within the scope of the invention.

Claims

1. A dielectric filter, comprising at least three connected dielectric resonators, each dielectric resonator comprising a body made of solid dielectric material and a tuning hole (4) located on the surface of the body; the bodies of all the dielectric resonators constitute the body of the dielectric filter; the surface of the body of the dielectric filter and the surface of the tuning hole (4) are covered with a conductive layer; characterized in that:

Two electrodes (2) are respectively arranged on the surfaces of two dielectric resonators located on one side of the input and output ports (3);

A transmission line (5) is arranged on a carrier; when the carrier is fixed on the dielectric resonator, the transmission line is suitable for connecting the two electrodes (2);

The carrier is a PCB (6), the transmission line (5) is formed in a dumbbell shape on the surface of the PCB (6), and green oil (7) is coated around the transmission line (5), and a plurality of PCB through holes (62) are opened on the periphery of the green oil (7).

2. The dielectric filter according to claim 1, characterized in that any one of the electrodes (2) is formed on the surface of the dielectric resonator by the conductive layer.

3. The dielectric filter according to claim 2, characterized in that the electrode (2) is circular, square or triangular.

4. The dielectric filter according to claim 1 is characterized in that the depth of the tuning hole (4), the area of the conductive layer covered in the tuning hole (4), and the position of the conductive layer in the tuning hole (4) are all related to the resonant frequency of the dielectric resonator in which the tuning hole (4) is located.

5 . The dielectric filter according to claim 1 , wherein the thickness of the conductive layer is greater than or equal to the skin depth.

6. The dielectric filter according to claim 5, characterized in that the conductive layer is a silver layer (11).

7. The dielectric filter according to claim 1, characterized in that the transmission line (5) is a copper layer of a PCB, a silver-plated wire or a silver-plated transmission rod.

8. The dielectric filter according to claim 1, wherein the solid dielectric material is a ceramic material.

9. The dielectric filter according to claim 8, characterized in that all dielectric resonator bodies are integrally formed using the same solid dielectric material.

10. A communication device, characterized by comprising at least one dielectric filter according to any one of claims 1 to 9.