Integrally-formed dielectric filter with multi-layer structure

Abstract

The invention provides an integrally-formed dielectric filter with a multilayer structure, which comprises a shell and a porcelain blank body, the shell is mounted outside the porcelain blank body, and the integrally-formed dielectric filter is characterized in that the porcelain blank body is of a multilayer structure, a plurality of resonant cavities are formed in each layer of the porcelain blank body, a blank body silver coating is coated outside the porcelain blank body except the front surface, and the ceramic blank body silver coating is coated outside the ceramic blank body. The surface and the inner wall of each resonant cavity are coated with a cavity silver coating. And the porcelain blank body is provided with a through groove for discharging interference coupling. The ceramic blank adopts a multi-layer structure and is fully utilized in the Z-axis direction, so that the size is optimized and the miniaturization effect is achieved under the condition that the performance of a dielectric filter is not consumed.

Description

Technical Field

[0001] The invention relates to a dielectric filter with an integrally formed multilayer structure. Background Art

[0002] With the development of the times and technology, the miniaturization of communication systems, such as base stations and WiFi, has become an inevitable trend. Especially for low-power systems such as WiFi, portability has become a functional requirement that goes hand in hand with performance.

[0003] Ceramic dielectric filters are an indispensable device for processing signals in base stations and WiFi systems. After years of development and technological iteration, they are no longer just about performance indicators, but also have increasingly stringent requirements on size.

[0004] The space in the communication system is set to three directions: X, Y, and Z. The plane composed of XY is a horizontal plane, which is mainly used for the layout of chips and components. The space is relatively cramped. Looking at the technical development history of ceramic dielectric filters, they are basically in-line and tiled structures. This structure mainly occupies the size of the XY horizontal area in space, and the use in the Z-axis direction is very limited.

[0005] Currently, the application of Monoblock in multi-layer structures is very limited. Generally, a split structure is adopted, that is, two independent dielectric filters are spliced ​​together. The process of this solution is complicated, and the splicing process increases the difficulty of the later process. In addition, the cost is relatively difficult to control. In addition, due to the influence of independent filters, it is often only possible to stack two layers of structure and cannot achieve a multi-layer effect. Summary of the invention

[0006] The purpose of the present invention is to address the above-mentioned problems in the prior art and to propose an integrated multi-layer dielectric filter. The ceramic body distributes the resonators in a multi-layer three-dimensional structure instead of a single horizontal in-line arrangement, and makes full use of the Z-axis direction, thereby optimizing the volume without consuming the performance of the dielectric filter and achieving a miniaturized effect.

[0007] The object of the present invention can be achieved by the following technical solution: A dielectric filter with an integrally formed multilayer structure, comprising a housing and a ceramic body, wherein the housing is mounted outside the ceramic body, and is characterized in that:

[0008] The ceramic embryo is a multi-layer structure and each layer is provided with a plurality of resonant cavities. The outside of the ceramic embryo is coated with a body silver-plated layer except for the front side, and the surface and inner wall of each resonant cavity are coated with a cavity silver-plated layer.

[0009] The ceramic blank is provided with a through groove for discharging interference coupling.

[0010] Furthermore, the ceramic body is made of ceramic material.

[0011] Furthermore, two sides of the lower end of the through slot are provided with a wire silver-plated layer, which are an input wire and an output wire respectively.

[0012] Furthermore, the multi-layer structure of the ceramic body comprises a first layer and a second layer, the first layer has four resonance cavities which are respectively located on both sides of the through groove, and the second layer has four resonance cavities arranged side by side.

[0013] Furthermore, the through groove is T-shaped and is located between the first layer and the second layer, and the lower end of the through groove is open and penetrates the ceramic blank.

[0014] Further, as another solution, the through groove is T-shaped and located in the middle of the ceramic blank.

[0015] Furthermore, as another solution, the multi-layer structure of the ceramic body has four layers, each layer has two resonance cavities, and the through groove is in the shape of a long strip and divides the resonance cavities of the lower three layers in the center.

[0016] Compared with the prior art, the advantages of this application are:

[0017] 1. The ceramic body adopts a multi-layer structure and makes full use of the Z-axis direction, so as to reduce the volume without consuming the performance of the dielectric filter and achieve the effect of miniaturization.

[0018] 2. The patent of the present invention adopts an integrated molding pressing process, and can easily realize the model design of multi-layer structure by adjusting the press and the mold, which greatly optimizes the process technology and realizes the structural design of any multi-layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic diagram of Embodiment 1;

[0020] Figure 2 This is a schematic diagram of Embodiment 1 with the housing removed;

[0021] Figure 3 is a schematic diagram of a ceramic embryo body of Example 1;

[0022] Figure 4 is a topological diagram of Embodiment 1;

[0023] Figure 5 is a schematic diagram of Embodiment 2;

[0024] Figure 6 This is a schematic diagram of Embodiment 2 with the housing removed;

[0025] Figure 7 is a topological diagram of Embodiment 2;

[0026] Figure 8 is a topology diagram of Embodiment 3;

[0027] In the figure, 1, shell; 2, ceramic body; 21, resonant cavity; 3, body silver plating layer; 31, cavity silver plating layer; 32, wire silver plating layer; 4, coupling path; 5, through slot. DETAILED DESCRIPTION

[0028] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention.

[0029] like Figure 1-4 As shown, a dielectric filter with an integrated multilayer structure comprises a housing 1 and a ceramic body 2, wherein the housing 1 is mounted outside the ceramic body 2, and is characterized in that:

[0030] The ceramic body 2 is a multi-layer structure and each layer is provided with a plurality of resonant cavities 21. The exterior of the ceramic body 2 except the front side is coated with a body silver-plated layer 3. The surface and inner wall of each resonant cavity 21 are coated with a cavity silver-plated layer 31.

[0031] The ceramic body 2 is provided with a through groove 5 for discharging interference coupling.

[0032] The Monoblock filter used in the present invention adopts the TEM mode working mode, and a section of the resonator (i.e., the ceramic body 2) is subjected to silver removal and open circuit processing to form a 1 / 4 wavelength. In addition, through the multi-layer distribution structure of the resonator, and then through the slotting ("T" slot, "I" slot, "I" slot) and other methods, the coupling path is normalized, thereby completing the design method of the three-dimensional topological structure.

[0033] Furthermore, the ceramic body 2 is made of ceramic material. The ceramic body 2 is an integrated structure and can have different heights.

[0034] Furthermore, the two sides of the lower end of the through slot 5 are provided with a wire silver-plated layer 32 and are respectively an input wire and an output wire. The input wire inputs a signal, and the output wire outputs a signal.

[0035] Furthermore, the multilayer structure of the ceramic body 2 is a first layer and a second layer, the first layer has four resonant cavities 21 respectively located on both sides of the through slot 5, and the second layer has four resonant cavities 21 arranged side by side. The resonant cavity adopts the TEM mode working mode, by removing a section of the silver layer of the resonator to form an open circuit, forming a 1 / 4 wavelength mode, and by plating a part of the silver layer on the open circuit, the resonator resonant frequency and coupling effect are controlled, thereby achieving the effect of establishing a passband.

[0036] The resonant cavity is divided into 2 layers, with 4 cavities in the first layer and 4 cavities in the second layer. The example is as follows. The plane occupies 9.80*6.84mm and the height is 580mm, making full use of the height space and reducing the space in the horizontal direction by half. If there is a large space margin in height, 4 layers can be stacked, with 2 resonant cavities distributed on each layer, then the plane space can be compressed to 7.80*6.84mm and the height is 7.80mm. In addition, the above stacked structure does not affect the performance of ceramic filter products.

[0037] Furthermore, the through groove 5 is T-shaped and is located between the first layer and the second layer, and the through groove 5 has an opening at the lower end and penetrates the ceramic body 2. Penetrating the ceramic body 2 allows the interference coupling to be completely discharged.

[0038] Compared with the in-line tile structure dielectric filter of the prior art, the present application reduces the length while keeping the width unchanged, and makes changes in the Z-axis direction to realize a laminated dielectric filter, with four resonant cavities 21 in the first layer and four resonant cavities 21 in the second layer, making full use of the height space and reducing the space by half in the horizontal direction. At the same time, through slots 5 are set by the slotting method to discharge the interference coupling generated by the bin setting, further realizing the normalization of the coupling path 4 and realizing the filter performance. The coupling path 4 is as shown in FIG. Figure 4 shown.

[0039] Embodiment 2

[0040] like Figure 5-7 As shown, further, as another solution, the through groove 5 is T-shaped and located in the middle of the ceramic body 2. The through groove 5 of this embodiment does not penetrate the lower end of the ceramic body 2.

[0041] Embodiment 3

[0042] like Figure 8 As shown, further, as another solution, the multi-layer structure of the ceramic body 2 has four layers, each layer has two resonance cavities 21, and the through groove 5 is in the shape of a long strip and centrally divides the resonance cavities 21 of the lower three layers.

[0043] If there is still a large space margin in height, four layers can be stacked, and two resonant cavities 21 can be opened in each layer, so that the plane space can be further compressed, and the interference coupling can be eliminated by the long strip through slot 5. The coupling path 4 of the third embodiment is as follows: Figure 8 shown.

[0044] The technical solution of the present invention provides a solution that is significantly different from the prior art to address the technical problem that the prior art solution is too single. The parts not involved in the technical solution of this application are the same as the prior art or can be implemented by using the prior art and will not be described in detail.

[0045] The technical solutions in the above embodiments have clearly and completely described the contents of the present invention. 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.

Claims

1. A dielectric filter with an integrally formed multilayer structure, comprising a housing and a ceramic body, wherein the housing is mounted outside the ceramic body, and characterized in that: The ceramic embryo is a multi-layer structure and each layer is provided with a plurality of resonant cavities. The outside of the ceramic embryo is coated with a body silver-plated layer except for the front side, and the surface and inner wall of each resonant cavity are coated with a cavity silver-plated layer. The ceramic blank is provided with a through groove for discharging interference coupling.

2. The dielectric filter of the integrally formed multilayer structure according to claim 1, characterized in that: The ceramic body is made of ceramic material.

3. The dielectric filter of the integrally formed multilayer structure according to claim 1, characterized in that: The multi-layer structure of the ceramic body comprises a first layer and a second layer, wherein the first layer has four resonance cavities respectively located on both sides of the through slot, and the second layer has four resonance cavities arranged side by side.

4. The dielectric filter of the integrally formed multilayer structure according to claim 3, characterized in that: The through groove is T-shaped and is located between the first layer and the second layer. The lower end of the through groove is open and penetrates the ceramic piece embryo body.

5. The dielectric filter of the integrally formed multilayer structure according to claim 3, characterized in that: The through groove is T-shaped and is located in the middle of the ceramic embryo body.

6. The dielectric filter with an integrally formed multilayer structure according to claim 1, characterized in that: The multi-layer structure of the ceramic body has four layers, each layer has two resonance cavities, and the through groove is in the shape of a long strip and divides the resonance cavities of the lower three layers in the middle.

7. The dielectric filter of the integrally formed multilayer structure according to claim 1, characterized in that: The two sides of the lower end of the through slot are provided with a wire body silver-plated layer, which are respectively an input wire body and an output wire body.

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