Dielectric filter and communication device having the same

Abstract

The dielectric filter provided by the present invention and the communication device having the dielectric filter belong to the field of communication technologies. The dielectric filter includes: a dielectric block having a front surface provided with a plurality of tuning holes and a back surface opposite to the front surface; a first blind groove that is not penetrated to the back surface of the dielectric block is provided between two of the tuning holes on the front surface of the dielectric block, and the depth of the first blind groove is greater than 0.5 times the thickness of the dielectric filter. In the dielectric filter of the present invention, a first blind groove that is not penetrated to the back surface of the dielectric block is provided between two of the tuning holes on the front surface of the dielectric block, and the depth of the first blind groove is greater than 0.5 times the thickness of the dielectric block. Through this first blind groove, it is possible to make the negative coupling between the tuning holes greater than the positive coupling without cascading an accessory structure outside the dielectric block, thereby meeting the requirements for miniaturization of the dielectric filter.

Description

Technical Field

[0001] The present invention relates to the field of communication technologies, and particularly to a dielectric filter and a communication device having the dielectric filter. Background Art

[0002] A dielectric filter is a microwave filter that uses dielectric tuning holes to achieve frequency selection through multi-stage coupling. In modern mobile communication technologies, dielectric filters have become an essential and important component, and are widely used in various mobile communication systems to filter out clutter or interference signals outside the communication signal frequency.

[0003] Like metal filters, to achieve high selectivity of a dielectric filter, cross-coupling needs to be formed in the dielectric filter. Cross-coupling is divided into two forms: capacitive coupling and inductive coupling. Capacitive coupling forms a transmission zero at the low end of the dielectric filter response, thereby forming high selectivity at the low end of the dielectric filter; inductive coupling forms a transmission zero at the high end of the dielectric filter response, thereby forming high selectivity at the high end of the dielectric filter.

[0004] Currently, in commonly used dielectric filters in the industry, the transmission zeros of the dielectric filter usually can only achieve inductive coupling. To achieve capacitive coupling of the dielectric filter, additional additional structures such as cascading a PCB or a cross-wire outside the dielectric are required. However, these additional structures cause inconvenience to the processing, assembly, and debugging of the dielectric filter.

[0005] With the increasing development of wireless communication technologies, the volume of base stations is required to be miniaturized. For the volume occupied by dielectric filters in base stations, miniaturization is also required. However, existing dielectric filters that can achieve capacitive coupling cannot meet the requirements of existing communication technologies for the miniaturization of base stations because additional attachment structures need to be cascaded outside the dielectric to achieve it. Summary of the Invention

[0006] Therefore, the present invention provides a dielectric filter capable of achieving negative coupling and a communication device having the dielectric filter.

[0007] To solve the above technical problems, the present invention provides a dielectric filter, including:

[0008] A dielectric block having a front surface provided with a plurality of tuning holes and a back surface opposite to the front surface;

[0009] A first blind groove that is not penetrated to the back surface of the dielectric block is provided between two of the tuning holes on the front surface of the dielectric block, and the depth of the first blind groove is greater than 0.5 times the thickness of the dielectric filter.

[0010] As a preferred solution, a second blind groove is provided on the reverse side of the dielectric block opposite to the first blind groove.

[0011] As a preferred solution, a positioning and adjusting groove for adjusting coupling is provided on the bottom surface of the first blind groove.

[0012] As a preferred solution, the positioning and adjusting groove penetrates into the second blind groove on the reverse side of the dielectric block.

[0013] As a preferred solution, a positioning and adjusting groove for adjusting coupling is provided on the bottom surface of the first blind groove.

[0014] As a preferred solution, the positioning and adjusting groove penetrates to the reverse side of the dielectric block.

[0015] As a preferred solution, the positioning and adjusting groove is located at one end close to the center of the dielectric block within the first blind groove.

[0016] As a preferred solution, one end of the first blind groove is communicated with a through groove provided on the dielectric block and penetrating through the front and back surfaces of the dielectric block.

[0017] As a preferred solution, the other end of the first blind groove penetrates to one side edge of the dielectric block.

[0018] The present invention also provides a communication device, including: the dielectric filter according to any one of the above solutions.

[0019] The technical solution of the present invention has the following advantages:

[0020] 1. For the dielectric filter provided by the present invention, a first blind groove that does not penetrate to the reverse side of the dielectric block is provided between two tuning holes on the front surface of the dielectric block, and the depth of the first blind groove is greater than 0.5 times the thickness of the dielectric block; through this first blind groove, it is possible to make the negative coupling between the tuning holes greater than the positive coupling without cascading an accessory structure outside the dielectric block, thereby meeting the requirements for miniaturization of the dielectric filter.

[0021] 2. For the dielectric filter provided by the present invention, a second blind groove is provided on the reverse side of the dielectric block opposite to the first blind groove. Through the setting of the second blind groove, it is easier for the dielectric filter to achieve negative coupling between the tuning holes.

[0022] 3. For the dielectric filter provided by the present invention, the positioning and adjusting groove for adjusting coupling provided on the bottom surface of the first blind groove can be used to perturb the negative coupling, thereby forming an easily adjustable negative coupling structure and realizing tunable negative coupling of a single-layer dielectric filter. And the positioning and adjusting groove is located at one end close to the center of the dielectric block within the first blind groove, so that its adjustment sensitivity is stronger and the adjustment amount can be increased.

[0023] 4. For the dielectric filter provided by the present invention, one end of the first blind slot communicates with the through slot that penetrates the front and back surfaces of the dielectric block, and the other end of the first blind slot penetrates to one side of the dielectric block. Such a setting facilitates the processing of the first blind slot.

[0024] 5. For the dielectric filter provided by the present invention, the dielectric block can be integrally formed, having very good consistency and mass production performance; having a negative coupling structure, combined with a positive coupling structure, can make the filter frequency response have transmission zeros, and have better out-of-band rejection compared to the frequency response of natural attenuation. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0026] Figure 1 It is a front perspective view of an embodiment of the dielectric filter of the present invention.

[0027] Figure 2 is Figure 1 the reverse perspective view of the dielectric filter.

[0028] Figure 3 It is a front perspective view of the second embodiment of the dielectric filter of the present invention.

[0029] Figure 4 It is the frequency response curve of the dielectric filter of the present invention.

[0030] DESCRIPTION OF THE REFERENCE NUMERALS:

[0031] 1, front surface; 2, reverse surface; 3, tuning hole; 4, through slot; 5, first blind slot; 6, second blind slot; 7, input port; 8, output port; 9, positioning and adjusting slot. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] The following will clearly and completely describe the technical solutions of the present invention with reference to the drawings. Obviously, the described embodiments are some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0033] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0034] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0036] Embodiment 1

[0037] This embodiment provides a dielectric filter, including: a dielectric block, the dielectric block having a front surface 1 provided with a plurality of tuning holes 3 and a back surface 2 opposite to the front surface 1.

[0038] As Figure 1 shown, in this embodiment, the front surface 11 of the dielectric block has four tuning holes 3 arranged in a matrix. The tuning holes 3 are blind holes with a circular structure, and the blind holes are expressed as not penetrating through to the other side of the dielectric block. On the front surface 1 of the dielectric block, there is also a through groove 4 that penetrates through the front and back surfaces of the dielectric block. The through groove 4 includes a transverse through groove and a longitudinal through groove. The through groove 4 divides the front surface 1 of the dielectric block into several regions, and at least one tuning hole 3 is provided in each region. Additionally, as an alternative embodiment, the tuning holes 3 can also be set to three, five or more.

[0039] A first blind groove 5 that does not penetrate through to the back surface 2 of the dielectric block is provided between two of the tuning holes 3 on the front surface 1 of the dielectric block. One end of the first blind groove 5 communicates with the middle of one of the transverse through grooves, and the other end of the first blind groove 5 is closed. The depth of the first blind groove 5 is greater than 0.5 times the thickness of the dielectric block.

[0040] As Figure 2As shown in the figure, on the reverse side 2 of the dielectric block, a second blind groove 6 is provided at a position opposite to the first blind groove 5, and the extending direction of the second blind hole is the same as that of the first blind hole. In addition, on the reverse side 2 of the dielectric block, input ports 7 and output ports 8 are respectively provided at positions opposite to two other adjacent tuning holes 3, and both the input port 7 and the output port 8 are blind holes.

[0041] A positioning adjustment groove 9 for adjusting coupling is provided at the bottom surface of the first blind groove 5. The positioning adjustment groove 9 is located at one end close to the center of the dielectric block within the first blind groove 5, and the positioning adjustment groove 9 penetrates into the second blind groove 6 on the reverse side 2. In addition, as an alternative embodiment, the positioning adjustment groove 9 can also be a blind hole that does not penetrate into the second blind groove 6.

[0042] The dielectric block is made of ceramic material, and a metal layer is covered on the outside of the dielectric block. In this embodiment, the metal of the metal layer is silver, and copper, tin, aluminum, etc. can also be used.

[0043] The metal layer avoids the shielding areas around the input port 7 and the output port 8 on the back surface of the dielectric block.

[0044] The metal layer covered in the tuning hole 3 on the front surface 1 of the dielectric block can be removed according to actual situations, so as to adjust the filter characteristics.

[0045] The metal layer covered in the positioning adjustment groove 9 on the front surface 1 of the dielectric block can be removed according to actual situations, so as to adjust the filter characteristics.

[0046] Embodiment 2

[0047] This embodiment provides a dielectric filter, which has a substantially the same structure as that of Embodiment 1. The difference is that: as Figure 3 shown, the dielectric block of this embodiment is only provided with a first blind groove 5 on the front surface 1, and one end of the first blind groove 5 communicates with the middle part of one of the transverse through grooves, and the other end of the first blind groove 5 penetrates to one side edge of the dielectric block.

[0048] In this embodiment, the positioning adjustment groove 9 located at the bottom surface of the first blind groove 5 is a blind hole that does not penetrate to the reverse side 2. In addition, as an alternative embodiment, the positioning adjustment groove 9 can be omitted.

[0049] Embodiment 3

[0050] This embodiment provides a dielectric filter, which has a substantially the same structure as that of Embodiment 1. The difference is that: one end of the first blind groove 5 of this embodiment communicates with the middle part of one of the transverse through grooves, and the other end of the first blind groove 5 penetrates to one side edge of the dielectric block. This structural setting can facilitate the processing of the first blind groove 5 and reduce the production cost.

[0051] As Figure 4 shown, it is the frequency response curve of the dielectric filter in this embodiment.

[0052] Embodiment 4

[0053] This embodiment provides a communication device, including at least one dielectric filter described in Embodiment 1, Embodiment 2 or Embodiment 3.

[0054] Obviously, the above embodiments are merely examples given for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all implementation manners here. And the obvious changes or modifications derived therefrom are still within the protection scope of the present invention.

Claims

1. A dielectric filter, characterized in that , comprising: A dielectric block having a front face (1) provided with a plurality of tuning holes (3) and a back face (2) opposite to the front face (1); a through groove (4) penetrating through the front and back faces of the dielectric block is provided on the dielectric block, the through groove (4) includes a transverse through groove and a longitudinal through groove, and the through groove (4) divides the front face (1) of the dielectric block into several regions, and at least one tuning hole (3) is provided in each region; A first blind groove (5) that does not penetrate to the back face (2) of the dielectric block is provided between two of the tuning holes (3) on the front face (1) of the dielectric block, the depth of the first blind groove (5) is greater than 0.5 times the thickness of the dielectric filter, and a second blind groove (6) is provided on the back face (2) of the dielectric block opposite to the first blind groove (5); One end of the first blind groove (5) communicates with the middle of one of the transverse through grooves, and a positioning adjustment groove (9) for adjusting coupling is provided on the bottom surface of the first blind groove (5), and the positioning adjustment groove (9) penetrates into the second blind groove (6) on the back face (2) of the dielectric block, and the positioning adjustment groove (9) is located at one end close to the center of the dielectric block in the first blind groove (5).

2. The dielectric filter according to claim 1, characterized in that, The other end of the first blind groove (5) penetrates to a side of the dielectric block.

3. A communication device, characterized in that, Comprising: The dielectric filter according to any one of claims 1 to 2.

Images