A dielectric filter and a communication device having the dielectric filter

Abstract

The present invention provides a dielectric filter and a communication device with the dielectric filter, belonging to the field of communication technology, wherein the dielectric filter comprises: a dielectric block, the 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 not penetrating to the front side of the dielectric block is provided between two tuning holes on the back side of the dielectric block, and the depth of the first blind groove is greater than 0.5 times the thickness of the dielectric block; the dielectric filter of the present invention has a first blind groove not penetrating to the front side of the dielectric block between two tuning holes on the back side 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 the first blind groove, the negative coupling between the tuning holes can be made greater than the positive coupling without cascading an accessory structure outside the dielectric block, thereby meeting the requirement for miniaturization of the dielectric filter.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular 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 through multi-stage coupling to achieve frequency selection. In modern mobile communication technology, dielectric filters have become an indispensable 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 dielectric filters, cross-coupling needs to be formed in the dielectric filters. 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] At present, in the dielectric filters commonly used in the industry, the transmission zero point of the dielectric filter can usually only realize inductive coupling. To realize the capacitive coupling of the dielectric filter, it is necessary to add additional structures such as cascade jumper PCB or jumper cable outside the dielectric. However, these additional structures cause inconvenience to the processing, assembly and debugging of the dielectric filter.

[0005] With the development of wireless communication technology, the size of base stations is required to be miniaturized. The volume occupied by dielectric filters in base stations is also required to be miniaturized. However, the existing dielectric filters that can achieve capacitive coupling need to be cascaded with accessory structures outside the dielectric, which makes the existing dielectric filters unable to meet the requirements of existing communication technology for miniaturization of base stations. Summary of the invention

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

[0007] In order to solve the above technical problems, the present invention provides a dielectric filter, comprising:

[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 which does not penetrate to the front side of the dielectric block is arranged between the two tuning holes on the reverse side of the dielectric block, and the depth of the first blind groove is greater than 0.5 times the thickness of the dielectric block.

[0010] As a preferred solution, a positioning adjustment groove for adjusting coupling is provided on the front side of the dielectric block opposite to the first blind groove.

[0011] As a preferred solution, the positioning adjustment groove is a groove that does not penetrate to the first blind groove.

[0012] As a preferred solution, the positioning adjustment groove is a circular groove or a strip groove.

[0013] 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 both the front and back surfaces of the dielectric block.

[0014] As a preferred solution, the other end of the first blind groove is closed.

[0015] As a preferred solution, the dielectric block is made of ceramic material, and the outside of the dielectric block is covered with a metal layer.

[0016] As a preferred solution, the metal of the metal layer includes any one of copper, silver, tin or aluminum.

[0017] As a preferred solution, the front surface of the dielectric block has at least a portion not covered by the metal layer.

[0018] The present invention also provides a communication device, comprising: a dielectric filter as described in any one of the above schemes.

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

[0020] 1. The dielectric filter provided by the present invention has a first blind groove that does not penetrate to the front side of the dielectric block and is located between two tuning holes on the back side 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 the first blind groove, the negative coupling between the tuning holes can be greater than the positive coupling without cascading an accessory structure outside the dielectric block, thereby meeting the requirements for miniaturization of the dielectric filter. In addition, the first blind groove is arranged on the back side of the dielectric block, which can more easily achieve negative coupling between the tuning holes than on the front side.

[0021] 2. The dielectric filter provided by the present invention can be used for perturbation negative coupling by setting positioning adjustment grooves, thereby forming an easily adjustable negative coupling structure and realizing tunable negative coupling of a single-layer dielectric filter.

[0022] 3. The dielectric filter provided by the present invention has one end of the first blind slot arranged on the reverse side of the dielectric block connected to the through slot penetrating the front and reverse sides of the dielectric block, and the other end of the first blind slot is closed. This structure can achieve the enclosure of the electromagnetic field.

[0023] 4. The dielectric filter provided by the present invention has a dielectric block that can be integrally formed and has very good consistency and mass production performance.

[0024] 5. The dielectric filter provided by the present invention has a negative coupling structure, which, in combination with a positive coupling structure, can make the filter frequency response have a transmission zero point and have better out-of-band suppression relative to the natural attenuation frequency response. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

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

[0027] Figure 2 for Figure 1 Rear perspective view of the dielectric filter.

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

[0029] Figure 4 It is a front perspective view of a third embodiment of the dielectric filter of the present invention.

[0030] Figure 5 FIG. 4 is a frequency response curve of the dielectric filter of the present invention.

[0031] Description of reference numerals:

[0032] 1. Front side; 2. Back side; 3. Tuning hole; 4. Through slot; 5. First blind slot; 6. Input port; 7. Output port; 8. Positioning adjustment slot. DETAILED DESCRIPTION

[0033] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are 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 cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0035] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0037] Example 1

[0038] This embodiment provides a dielectric filter, comprising: a dielectric block, wherein the dielectric block has a front surface 1 provided with a plurality of tuning holes 3 and a back surface 2 opposite to the front surface 1 .

[0039] like Figure 1 As shown, in this embodiment, the front side 1 of the dielectric block has six tuning holes 3 arranged in a matrix, and the tuning holes 3 are blind holes of a circular structure, which are indicated as not penetrating to the other side of the dielectric block. The front side 1 of the dielectric block also has a through slot 4 penetrating the front and back sides of the dielectric block, and the through slot 4 includes a transverse through slot and a longitudinal through slot, and the through slot 4 divides the front side 1 of the dielectric block into several areas, each of which has at least one tuning hole 3. In addition, as an alternative embodiment, the tuning holes 3 can also be set to three, four, five or more.

[0040] like Figure 2As shown, a first blind groove 5 not penetrating to the front side 1 of the dielectric block is provided on the reverse side 2 of the dielectric block between the two tuning holes 3, one end of the first blind groove 5 is connected to 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. An input port 6 and an output port 7 are provided on the reverse side 2 of the dielectric block at positions respectively opposite to the other two adjacent tuning holes 3, and both the input port 6 and the output port 7 are blind holes.

[0041] The dielectric block is made of ceramic material, and the outside of the dielectric block is covered with a metal layer. In this embodiment, the metal of the metal layer is silver, and copper, tin or aluminum can also be used.

[0042] The metal layer avoids the shielding area around the input port 6 and the output port 7 on the back side of the dielectric block.

[0043] The metal layer covering the tuning hole 3 of the front side 1 of the dielectric block can be removed according to actual conditions to adjust the filter characteristics.

[0044] Example 2

[0045] This embodiment provides a dielectric filter, which has a substantially similar structure to that of the first embodiment, except that: Figure 3 As shown, the front side 1 of the dielectric block of this 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 that does not penetrate the first blind groove 5. The positioning adjustment groove 8 is used to perturb the negative coupling, thereby forming an easily adjustable negative coupling structure, and realizing the tunable negative coupling of the single-layer dielectric filter.

[0046] The positioning adjustment groove 8 of this embodiment is a circular groove. In addition, as an alternative embodiment, the positioning groove can also be Figure 4 The strip groove shown has the same direction as the first blind groove 5 .

[0047] The dielectric block of this embodiment is also made of ceramic material, and is covered with a metal layer on the outside of the dielectric block. The metal layer is in the positioning adjustment slot 8 on the front side 1 of the dielectric block and can be removed according to actual conditions to adjust the filter characteristics.

[0048] like Figure 5 As shown, it is the frequency response curve of the dielectric filter in this embodiment.

[0049] Example 3

[0050] This embodiment provides a communication device, including at least one dielectric filter described in Embodiment 1 or Embodiment 2.

[0051] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled 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 the implementation methods here. However, the obvious changes or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. A dielectric filter, characterized in that ,include: A dielectric block, the dielectric block comprising a front surface (1) provided with a plurality of tuning holes (3) and a rear surface (2) opposite to the front surface (1); A first blind groove (5) is provided on the reverse side (2) of the dielectric block between the two tuning holes (3) and does not penetrate to the front side (1) of the dielectric block, and the depth of the first blind groove (5) is greater than 0.5 times the thickness of the dielectric block; A through slot (4) passes through both sides of the dielectric block, the through slot (4) comprising a transverse through slot and a longitudinal through slot, one end of the first blind slot (5) is connected to the middle of one of the transverse through slots, and the other end of the first blind slot (5) is closed.

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

3. The 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. The dielectric filter according to claim 2, characterized in that: The positioning adjustment groove (8) is a circular groove or a strip groove.

5. The dielectric filter according to claim 1, characterized in that: The dielectric block is made of ceramic material, and the outside of the dielectric block is covered with a metal layer.

6. The dielectric filter according to claim 5, characterized in that The metal of the metal layer includes any one of copper, silver, tin or aluminum.

7. The dielectric filter according to claim 5, characterized in that The front side (1) of the dielectric block has at least a portion not covered by the metal layer.

8. A communication device, characterized in that: include: The dielectric filter according to any one of claims 1 to 7.

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