CN111162356A

CN111162356A - Dielectric filter and communication device with same

Info

Publication number: CN111162356A
Application number: CN202010054880.6A
Authority: CN
Inventors: 李�杰; 吴文敬; 王浩; 吴亚晖
Original assignee: Shenzhen Tatfook Technology Co Ltd
Current assignee: Shenzhen Tatfook Technology Co Ltd
Priority date: 2020-01-17
Filing date: 2020-01-17
Publication date: 2020-05-15

Abstract

The invention provides a dielectric filter and a communication device with the same, belonging to the technical field of communication, wherein the dielectric filter comprises: a dielectric block having a front side provided with a plurality of tuning holes and a back side opposite to the front side; a first blind groove which is not communicated to the front side of the dielectric block is arranged between the two tuning holes on the back side of the dielectric block, and the depth of the first blind groove is more than 0.5 time of the thickness of the dielectric block; according to the dielectric filter, a first blind groove which is not communicated to the front side of a dielectric block is arranged between two tuning holes on the back side of the dielectric block, and the depth of the first blind groove is more than 0.5 time of the thickness of the dielectric block; through the first blind slot, the negative coupling between the tuning holes can be larger than the positive coupling without a cascade accessory structure outside the dielectric block, thereby meeting the requirement on the miniaturization of the dielectric filter.

Description

Dielectric filter and communication device with same

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a dielectric filter and a communications device having the same.

Background

A Dielectric filter (Dielectric filter) is a microwave filter that uses a Dielectric tuning hole to achieve frequency selection through multi-stage coupling. In modern mobile communication technology, a dielectric filter has become an essential important component, and is widely applied to various mobile communication systems for filtering out noise waves or interference signals outside communication signal frequencies.

As with the metal filter, achieving high selectivity of the dielectric filter requires cross-coupling to be formed in the dielectric filter. The cross coupling is divided into two forms of capacitive coupling and inductive coupling, wherein the capacitive coupling is to form a transmission zero at the low end of the response of the dielectric filter so as to form high selectivity of the low end of the dielectric filter; inductive coupling is the formation of transmission zeros at the high end of the dielectric filter response, thus creating high selectivity at the high end of the dielectric filter.

At present, in a dielectric filter commonly used in the industry, a transmission zero of the dielectric filter can only realize inductive coupling, and an additional structure such as a PCB or a jumper cable needs to be cascaded outside a medium to realize capacitive coupling of the dielectric filter. However, these additional structures cause inconvenience in the fabrication, assembly and debugging of the dielectric filter.

With the increasing development of wireless communication technology, the volume miniaturization of base stations is required. The volume occupied by the dielectric filter in the base station also needs to be miniaturized, and the existing dielectric filter capable of realizing capacitive coupling can be realized only by a cascade attachment structure outside the medium, so that the existing dielectric filter cannot meet the requirement of the existing communication technology on the miniaturization of the base station.

Disclosure of Invention

Accordingly, the present invention provides a dielectric filter capable of realizing negative coupling and a communication device having the dielectric filter.

In order to solve the above-mentioned technical problem, the present invention provides a dielectric filter including:

a dielectric block having a front side provided with a plurality of tuning holes and a back side opposite to the front side;

and a first blind groove which is not communicated to the front side of the dielectric block is arranged between the two tuning holes on the back side of the dielectric block, and the depth of the first blind groove is more than 0.5 time of the thickness of the dielectric block.

Preferably, a positioning adjustment groove for adjusting coupling is formed in a front surface of the dielectric block opposite to the first blind groove.

Preferably, the positioning adjustment groove is a groove which does not penetrate through to the first blind groove.

Preferably, the positioning and adjusting groove is a circular groove or a strip-shaped groove.

Preferably, one end of the first blind groove is communicated with a through groove which is arranged on the dielectric block and penetrates through the front surface and the back surface of the dielectric block.

Preferably, the other end of the first blind groove is closed.

Preferably, the dielectric block is made of ceramic, and a metal layer covers the outside of the dielectric block.

Preferably, the metal of the metal layer includes any one of copper, silver, tin, or aluminum.

Preferably, the front surface of the dielectric block is at least partially uncovered by the metal layer.

The present invention also provides a communication apparatus comprising: the dielectric filter of any of the above aspects.

The technical scheme of the invention has the following advantages:

1. according to the dielectric filter provided by the invention, a first blind groove which is not penetrated to the front side of a dielectric block is arranged between two tuning holes on the back side of the dielectric block, and the depth of the first blind groove is more than 0.5 times the thickness of the dielectric block; through the first blind slot, the negative coupling between the tuning holes can be larger than the positive coupling without a cascade accessory structure outside the dielectric block, thereby meeting the requirement on the miniaturization of the dielectric filter. And, set up the first blind groove at the reverse side of dielectric block, compare and set up in the front, can realize the negative coupling between the tuning hole more easily.

2. The dielectric filter provided by the invention can be used for perturbation negative coupling by arranging the positioning adjusting groove, so that an easily-adjusted negative coupling structure is formed, and tunable negative coupling of a single-layer dielectric filter is realized.

3. According to the dielectric filter provided by the invention, one end of the first blind groove arranged on the reverse side of the dielectric block is communicated with the through groove penetrating through the front side and the reverse side of the dielectric block, and the other end of the first blind groove is sealed, so that an electromagnetic field can be sealed in the structure.

4. The dielectric filter provided by the invention has the advantages that the dielectric blocks can be integrally formed, and the consistency and the mass production are very good.

5. The dielectric filter provided by the invention has a negative coupling structure, and can enable the frequency of the filter to correspondingly have a transmission zero point by combining with a positive coupling structure, and the frequency of the filter has better out-of-band rejection relative to the naturally attenuated frequency.

Drawings

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

Fig. 1 is a front perspective view of one embodiment of a dielectric filter of the present invention.

Fig. 2 is a reverse perspective view of the dielectric filter of fig. 1.

Fig. 3 is a front perspective view of a dielectric filter according to a second embodiment of the present invention.

Fig. 4 is a front perspective view of a dielectric filter according to a third embodiment of the present invention.

Fig. 5 is a frequency response curve of the dielectric filter of the present invention.

Description of reference numerals:

1. a front side; 2. the reverse side; 3. a tuning hole; 4. a through groove; 5. a first blind slot; 6. an input port; 7. an output port; 8. and positioning the adjusting groove.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" 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, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

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

Example 1

The present embodiment provides a dielectric filter including: a dielectric block having a front side 1 provided with a plurality of tuning holes 3 and a back side 2 opposite to the front side 1.

As shown in fig. 1, in the present embodiment, the front surface 1 of the dielectric block has six tuning holes 3 arranged in a matrix, and the tuning holes 3 are blind holes with a circular structure, which are shown as not penetrating to the other surface of the dielectric block. The front surface 1 of the dielectric block is also provided with a through groove 4 penetrating through the front surface and the back surface of the dielectric block, the through groove 4 comprises a transverse through groove and a longitudinal through groove, the front surface 1 of the dielectric block is divided into a plurality of areas by the through groove 4, and each area is at least provided with one tuning hole 3. In addition, as an alternative embodiment, the tuning holes 3 may also be provided in three, four, five or more.

As shown in fig. 2, a first blind groove 5 which is not penetrated to the front 1 of the dielectric block is arranged between the two tuning holes 3 on the back 2 of the dielectric block, one end of the first blind groove 5 is communicated with the middle part of one transverse through groove, and the other end of the first blind groove 5 is closed. The depth of the first blind groove 5 is more than 0.5 time of the thickness of the medium block. And an input port 6 and an output port 7 are respectively arranged at positions, opposite to the other two adjacent tuning holes 3, on the back surface 2 of the dielectric block, and the input port 6 and the output port 7 are both blind holes.

The dielectric block is made of ceramic materials, and a metal layer covers the outside of the dielectric block. In this embodiment, silver is used as the metal of the metal layer, and copper, tin, aluminum, or the like may be used.

The metal layer avoids the shielded areas around the input port 6 and the output port 7 on the back of the dielectric block.

The metal layer of the dielectric block covered in the tuning hole 3 of the front surface 1 can be removed according to the actual situation, so as to adjust the filter characteristic.

Example 2

The present embodiment provides a dielectric filter having substantially the same structure as that of embodiment 1, except that: as shown in fig. 3, the front surface 1 of the dielectric block of the present embodiment is provided with a positioning adjustment groove 8 for adjusting coupling at a position opposite to the first blind groove 5, and the positioning adjustment groove 8 is a groove which does not penetrate through to the first blind groove 5. The positioning adjusting groove 8 is used for perturbation negative coupling, so that an easily adjustable negative coupling structure is formed, and tunable negative coupling of the single-layer dielectric filter is realized.

The positioning adjustment groove 8 of the present embodiment is a circular groove, and as an alternative embodiment, the positioning groove may also be a strip-shaped groove as shown in fig. 4, and the orientation of the strip-shaped groove is the same as the direction of the first blind groove 5.

The dielectric block of this embodiment is made of ceramic material, and the exterior of the dielectric block is covered with a metal layer. The metal layer is arranged in the positioning adjusting groove 8 on the front surface 1 of the dielectric block and can be removed according to actual conditions, so that the filter characteristics are adjusted.

Fig. 5 shows a frequency response curve of the dielectric filter in this embodiment.

Example 3

This embodiment provides a communication device including at least one dielectric filter described in embodiment 1 or embodiment 2.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are intended to be within the scope of the invention.

Claims

1. A dielectric filter, comprising:

a dielectric block having a front side (1) provided with a plurality of tuning holes (3) and a back side (2) opposite to the front side (1);

a first blind groove (5) which is not communicated to the front surface (1) of the medium block is arranged between the two tuning holes (3) on the back surface (2) of the medium block, and the depth of the first blind groove (5) is more than 0.5 time of the thickness of the medium block.

2. A dielectric filter according to claim 1, characterized in that a positioning adjustment groove (8) for adjusting coupling is provided on the front surface (1) of the dielectric block opposite to the first blind groove (5).

3. A dielectric filter according to claim 2, characterized in that the positioning adjustment groove (8) is a groove that does not penetrate to the first blind groove (5).

4. A dielectric filter according to claim 2, characterized in that the positioning adjustment groove (8) is a circular groove or a strip-shaped groove.

5. The dielectric filter according to claim 1, wherein one end of the first blind groove (5) is communicated with a through groove (4) which is arranged on the dielectric block and penetrates through the front and back surfaces of the dielectric block.

6. A dielectric filter as claimed in claim 5, characterized in that the other end of the first blind slot (5) is closed.

7. The dielectric filter of claim 1, wherein the dielectric block is made of ceramic, and the exterior of the dielectric block is covered with a metal layer.

8. The dielectric filter of claim 7, wherein the metal of the metal layer comprises any of copper, silver, tin, or aluminum.

9. A dielectric filter as claimed in claim 7, characterized in that the front side (1) of the dielectric block has at least a part which is not covered by the metal layer.

10. A communications apparatus, comprising: a dielectric filter as claimed in any one of claims 1 to 9.