阅读说明：本技术 一种具有跨腔耦合结构的介质波导滤波器 (dielectric waveguide filter with cross-cavity coupling structure ) 是由 徐国庆 叶荣 王斌华 廖东 于 2019-10-29 设计创作，主要内容包括：本发明提供了一种具有跨腔耦合结构的介质波导滤波器,所述介质波导滤波器包括有依次连接的至少三个谐振单元,每相邻的两个所述谐振单元之间设有一个耦合窗口；在至少一对非相邻的第一谐振单元和第二谐振单元上分别设有至少一个第一耦合盲孔和第二耦合盲孔,且所述第一耦合盲孔和所述第二耦合盲孔之间相互电气连接,以使非相邻的所述第一谐振单元和所述第二谐振单元产生交叉耦合。借此,本发明通过在非相邻的两个谐振单元之间引入跨腔耦合结构来实现跨腔耦合,增加介质波导滤波器的传输零点,从而能够在不增加滤波器的体积的情况下,进一步提高介质波导滤波器的频率选择特性,并且具有实现结构简单,便于制造和维护的特点。(The invention provides dielectric waveguide filters with cavity-crossing coupling structures, which comprise at least three resonance units connected in sequence, coupling windows are arranged between every two adjacent resonance units, at least fourth coupling blind holes and second coupling blind holes are respectively arranged on th and second resonance units which are not adjacent at least pairs, and the th coupling blind holes and the second coupling blind holes are mutually electrically connected so as to enable the th resonance units and the second resonance units which are not adjacent to each other to generate cross coupling.)

The dielectric waveguide filter with the cavity-crossing coupling structure is characterized by comprising at least three resonance units which are connected in sequence, coupling windows are arranged between every two adjacent resonance units, at least coupling blind holes and at least second coupling blind holes are arranged on the th resonance unit and the second resonance unit which are not adjacent to each other of at least pairs of resonance units, and the th coupling blind hole and the second coupling blind hole are electrically connected with each other, so that the th resonance unit and the second resonance unit which are not adjacent to each other generate cross coupling.

2. The dielectric waveguide filter of claim 1, wherein the side surfaces of the th resonant unit and the second resonant unit which are not adjacent to each other are provided with the th coupling blind hole, the second coupling blind hole and at least 0 circuit boards, the th coupling blind hole and the second coupling blind hole are respectively provided with a th metal inner core and a second metal inner core, the circuit boards are provided with at least th metal wires, and the th metal wires are respectively connected with the th metal inner core of the th coupling blind hole and the second metal inner core of the second coupling blind hole to realize the electrical connection between the th coupling blind hole and the second coupling blind hole, or

The lateral surfaces of the th resonance unit and the second resonance unit which are not adjacent to each other are provided with the coupling blind hole, the second coupling blind hole and at least second metal wires, th metal inner cores and second metal inner cores are respectively arranged in the coupling blind hole and the second coupling blind hole, and the second metal wires are respectively connected with the th metal inner core of the coupling blind hole and the second metal inner core of the second coupling blind hole, so that the coupling blind hole and the second coupling blind hole are electrically connected.

3. The dielectric waveguide filter of claim 2, wherein the circuit board has a three-layer structure comprising a bottom metal layer, a middle dielectric layer and a top metal layer, at least of the metal lines are etched on the top metal layer, the metal lines are electrically connected with the metal core of the coupling blind via and the second metal core of the second coupling blind via through-metallization vias on the circuit board, and/or

The circuit board is a hard circuit board or a flexible circuit board.

4. The dielectric waveguide filter of claim 2, wherein the th metal line or the second metal line is a suspended line, a microstrip line or a coplanar waveguide, and/or

The th metal wire or the second metal wire is in a straight line shape, a fold line shape or a curve shape.

5. The dielectric waveguide filter of claim 1, wherein the th and second coupling blind holes are cylindrical, elliptic cylindrical, or prismatic.

6. A dielectric waveguide filter according to claim 1, wherein the top of each of the resonator elements is provided with at least tuning blind holes for tuning the resonant frequency of the resonator element, and/or

The at least three resonance units are arranged in a straight line, a curve line or a broken line.

7. A dielectric waveguide filter according to claim 6, wherein the tuning blind hole is provided at the center of the top of the resonator unit.

8. The dielectric waveguide filter of claim 1 wherein th metallization is attached to the outer surface of the dielectric waveguide filter, wherein the st and second coupling blind vias have second metallization on their inner walls, and wherein circles of th and second electroless regions are provided on the outer edges of the st and second coupling blind vias, respectively, wherein the th electroless region separates the second metallization of the st coupling blind via from the th metallization of the dielectric waveguide filter, and the second electroless region separates the second metallization of the second coupling blind via from the th metallization of the dielectric waveguide filter.

9. The dielectric waveguide filter of claim 8 wherein the th electroless plated region and the second electroless plated region are circular or polygonal.

10. The dielectric waveguide filter of any of claims 1-9, wherein the coupling strength of the non-adjacent th and second resonant cells is controlled by the depths of the th and second coupling blind holes, the coupling strength is larger the deeper the th and second coupling blind holes are, and/or

The size of the coupling strength of the th resonance unit and the second resonance unit which are not adjacent to each other is controlled by the position relationship between the bottoms of the th coupling blind hole and the second coupling blind hole and the th resonance unit and the second resonance unit respectively, the coupling strength is maximum when the bottoms of the th coupling blind hole and the second coupling blind hole are at the middle position of the th resonance unit and the second resonance unit, and the coupling strength is weaker when the bottoms of the th coupling blind hole or the second coupling blind hole are closer to the upper end position and the lower end position of the th resonance unit and the second resonance unit.

Technical Field

The invention relates to a dielectric waveguide filter in the technical field of communication, in particular to dielectric waveguide filters with a cavity-crossing coupling structure.

Background

However, with the continuous development of the multi-frequency system, the requirements on the volume and frequency selection characteristics of the filter are higher and higher, however, the volume of the dielectric waveguide filter is generally greatly increased to achieve the required frequency selection characteristics in the existing dielectric waveguide filter, and therefore, how to improve the frequency selection characteristics of the dielectric waveguide filter in steps is a problem to be solved at present.

In view of the above, the prior art is obviously inconvenient and disadvantageous in practical use, and needs to be improved.

Disclosure of Invention

In view of the above-mentioned drawbacks, the present invention provides dielectric waveguide filters having a cavity-crossing coupling structure, which can further steps improve the frequency selective characteristics of the dielectric waveguide filter without increasing the size of the filter.

In order to achieve the above object, the present invention provides dielectric waveguide filters having a cross-cavity coupling structure, the dielectric waveguide filter includes at least three resonant units connected in sequence, coupling windows are provided between every two adjacent resonant units, at least coupling blind holes and at least second coupling blind holes are provided on at least pairs of non-adjacent and second resonant units, and the coupling blind holes and the second coupling blind holes are electrically connected to each other, so that the non-adjacent resonant units and the second resonant units generate cross coupling.

According to the dielectric waveguide filter, the lateral surfaces of the th resonance unit and the second resonance unit which are not adjacent are provided with the th coupling blind hole, the second coupling blind hole and at least 0 circuit boards, the th coupling blind hole and the second coupling blind hole are internally provided with the th metal inner core and the second metal inner core respectively, the circuit board is provided with at least th metal wires, and the th metal wire is connected with the th metal inner core of the th coupling blind hole and the second metal inner core of the second coupling blind hole respectively to realize the electrical connection between the th coupling blind hole and the second coupling blind hole, or

The lateral surfaces of the th resonance unit and the second resonance unit which are not adjacent to each other are provided with the coupling blind hole, the second coupling blind hole and at least second metal wires, th metal inner cores and second metal inner cores are respectively arranged in the coupling blind hole and the second coupling blind hole, and the second metal wires are respectively connected with the th metal inner core of the coupling blind hole and the second metal inner core of the second coupling blind hole, so that the coupling blind hole and the second coupling blind hole are electrically connected.

According to the dielectric waveguide filter, the circuit board is of a three-layer structure and sequentially comprises a bottom metal layer, a middle dielectric layer and a top metal layer, at least pieces of th metal wires are etched on the top metal layer, the th metal wires are electrically connected with the th metal inner core of the th coupling blind hole and the second metal inner core of the second coupling blind hole through metalized through holes in the circuit board respectively, and/or

The circuit board is a hard circuit board or a flexible circuit board.

According to the dielectric waveguide filter, the th metal wire or the second metal wire is a suspension wire, a microstrip line or a coplanar waveguide, and/or

The th metal wire or the second metal wire is in a straight line shape, a fold line shape or a curve shape.

According to the dielectric waveguide filter, the th coupling blind hole and the second coupling blind hole are cylindrical, elliptic cylindrical or prismatic.

According to the dielectric waveguide filter, the top of each resonance unit is provided with at least tuning blind holes for tuning the resonance frequency of the resonance unit, and/or

The at least three resonance units are arranged in a straight line, a curve line or a broken line.

According to the dielectric waveguide filter of the present invention, the tuning blind hole is provided at the center of the top of the resonance unit.

According to the dielectric waveguide filter, th metal plating layers are attached to the outer surface of the dielectric waveguide filter, second metal plating layers are respectively arranged on the inner walls of the coupling blind hole and the second coupling blind hole, circles of th electroless plating areas and second electroless plating areas are respectively arranged on the outer edges of the coupling blind hole and the second coupling blind hole, the second metal plating layers of the coupling blind hole and the th metal plating layers of the dielectric waveguide filter are separated by the th electroless plating areas, and the second metal plating layers of the second coupling blind hole and the th metal plating layers of the dielectric waveguide filter are separated by the second electroless plating areas.

According to the dielectric waveguide filter, the th non-plating area and the second non-plating area are circular rings or polygons.

According to the dielectric waveguide filter, the coupling strength of the non-adjacent th resonance unit and the second resonance unit is controlled by the depth of the th coupling blind hole and the second coupling blind hole, the deeper the depth of the th coupling blind hole and the second coupling blind hole is, the greater the coupling strength is, and/or

The size of the coupling strength of the th resonance unit and the second resonance unit which are not adjacent to each other is controlled by the position relationship between the bottoms of the th coupling blind hole and the second coupling blind hole and the th resonance unit and the second resonance unit respectively, the coupling strength is maximum when the bottoms of the th coupling blind hole and the second coupling blind hole are at the middle position of the th resonance unit and the second resonance unit, and the coupling strength is weaker when the bottoms of the th coupling blind hole or the second coupling blind hole are closer to the upper end position and the lower end position of the th resonance unit and the second resonance unit.

The invention has dielectric waveguide filter with coupling structure of crossing the cavity including at least three resonance units connected sequentially, said dielectric waveguide filter has to resonance units and second resonance units not adjacent respectively coupled with coupling blind hole and second coupling blind hole, and couples the blind hole and second coupling blind hole to each other electrically, thus make resonance units and second resonance units not adjacent produce the cross coupling of crossing the cavity, and can produce transmission zeros near the passband.

Drawings

Fig. 1 is a schematic diagram of a preferred structure of a dielectric waveguide filter having a cross-cavity coupling structure according to the present invention.

Detailed Description

For purposes of making the objects, aspects and advantages of the present invention more apparent, the present invention will be described in detail below with reference to the accompanying drawings and examples.

It is noted that references in this specification to " embodiments," "an embodiment," "an example embodiment," etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic.

In addition, while the specification and claims hereinafter may refer to particular components or elements using certain terminology, those skilled in the art will understand that the manufacturer may refer to components or elements using different names or terms.

The invention has dielectric waveguide filter which crosses the cavity coupling structure to include at least three resonance units connected sequentially, the said resonance unit is connected in arbitrary topological structure, and there are coupling windows between every two adjacent resonance units. No. coupling blind holes and second coupling blind holes are set on resonance units and second resonance units which are not adjacent at least , and coupling blind holes and second coupling blind holes are connected electrically, make resonance units and second resonance units which are not adjacent form cross coupling, thus produce transmission zero points near the pass band, on the premise of not increasing the volume of the dielectric waveguide filter, can go on step to improve the frequency selective characteristic of the dielectric waveguide filter.

Fig. 1 shows a preferred structure of a dielectric waveguide filter having a cross-cavity coupling structure according to the present invention, where the dielectric waveguide filter 100 includes five resonant units 101 to 105 connected in sequence, and in this embodiment, the resonant units 101 to 105 are arranged in a straight line in sequence, but each resonant unit of the dielectric waveguide filter 100 of the present invention may be connected in any topological structure as required, for example, the resonant units 101 to 105 may also be arranged in a curve or a polygonal line in sequence, and coupling windows 201 to 204 are respectively disposed between each two adjacent resonant units, and the coupling windows 201 to 204 may be hollow cavity structures, specifically, a coupling window 201 is disposed between the adjacent resonant units 101 to 102, a coupling window 202 is disposed between the adjacent resonant units 102 to 103, a coupling window 203 is disposed between the adjacent resonant units 103 to 104, and a coupling window 204 is disposed between the adjacent resonant units 104 to 105.

In the embodiment shown in FIG. 1, the dielectric waveguide filter 100 is composed of five resonant units 101 to 105 and four coupling windows 201 to 204, and the resonant units 101 to 105 and the coupling windows 201 to 204 are arranged in an alternating straight line. It should be noted that the number n of the resonant units of the dielectric waveguide filter 100 of the present invention is equal to or greater than 3, and the number of the coupling windows is n-1. The specific number of the resonance units is not limited, and the number of the resonance units can be increased or decreased arbitrarily according to actual needs as long as n is more than or equal to 3. For example, the dielectric waveguide filter 100 may include three, four, six, seven, eight, nine, ten, or more resonant cells.

In order to further step improve the frequency selective characteristic of the dielectric waveguide filter, the invention proposes to introduce cross-cavity coupling structures between at least pairs of non-adjacent two resonant units of the dielectric waveguide filter 100 to realize cross-cavity coupling, as shown in fig. 1, at least of the coupling blind holes 301 and the second coupling blind holes 302 are preferably arranged on the non-adjacent th resonant unit 102 and the second resonant unit 104 respectively, and the coupling blind holes 301 and the second coupling blind holes 302 are electrically connected with each other, so that the non-adjacent resonant unit 102 and the second resonant unit 104 form cross-cavity coupling, thereby generating transmission zeros near a pass band, and improving the frequency selective characteristic of the dielectric waveguide filter 100 without increasing the volume of the dielectric waveguide filter 100.

In the embodiment shown in fig. 1, the lateral surfaces of the th resonant unit 102 and the second resonant unit 104 which are not adjacent to each other are provided with a th coupling blind hole 301, a second coupling blind hole 302 and at least 0 circuit boards 501, the 1 th coupling blind hole 301 and the second coupling blind hole 302 are respectively provided with a th metal inner core 401 and a second metal inner core 402, the circuit board 501 is provided with at least th metal wire 502, two ends of the metal wire 502 are respectively connected with the th metal inner core 401 of the th coupling blind hole 301 and the second metal inner core 402 of the second coupling blind hole 302, and the th metal inner core 401 and the second metal inner core 402 are used for electrically connecting the th metal wire 502 on the circuit board 501 with the two coupling blind holes 301-302, so as to generate cross coupling between the non-adjacent resonant units 102 and 104.

Of course, the th coupling blind via 301, the second coupling blind via 302, and the circuit board 501 are not limited to be disposed on the side surfaces of the non-adjacent resonant cells 102 and 104, and may be disposed on the top and bottom of the non-adjacent resonant cells 102 and 104 according to actual requirements.

The th coupling blind hole 301 and the second coupling blind hole 302 in FIG. 1 are preferably cylindrical, but the th coupling blind hole 301 and the second coupling blind hole 302 can also be any regular geometric column or irregular geometric column such as an elliptic column or a prism.

Preferably, the circuit board 501 is a three-layer structure, which sequentially includes a bottom metal layer, a middle dielectric layer and a top metal layer (not shown), at least metal wires 502 of the can be etched on the top metal layer, the metal wire 502 is electrically connected to the inner core 401 of the metal of the coupling blind via 301 and the inner core 402 of the second coupling blind via 302 through a metalized through hole on the circuit board 501, the circuit board 501 can be a rigid circuit board or a flexible circuit board, and the flexible circuit board can be applied to the case where the non-adjacent resonant units 102 and 104 are arranged in a non-linear manner, such as a curved line arrangement or a broken line arrangement.

It should be noted that the electrical connection between the coupling blind via 301 and the second coupling blind via 301 of is not limited to the combination of the circuit board 501 and the metal line 502 of as shown in fig. 1. in another 4930 embodiment of the present invention, the sides of the non-adjacent resonance unit 102 and the second resonance unit 104 are provided with the coupling blind via 301 of th 2, the coupling blind via 302 of second and at least second metal lines (not shown), the coupling blind via 301 of th and the second coupling blind via 302 are provided with the metal core 401 of th and the metal core 402 respectively, said second metal lines are connected to the metal core 401 of th of the coupling blind via 301 of th and the metal core 402 of the second coupling blind via 302 respectively, so as to realize the electrical connection between the coupling blind via 301 of th and the second coupling blind via 302, that the coupling blind via 301 of th and the second coupling blind via 301 can be directly connected via the second metal line without adding the coupling blind via 102 of the non-adjacent resonance unit 301 and the second coupling blind via 302, thereby increasing the frequency selective transmission filter 36100.

The th metal line 502 or the second metal line can be any type of suspended line, microstrip line or coplanar waveguide, preferably a suspended line, and the metal line in the present invention actually only has an electrical connection function, so the specific shape is not limited, for example, the th metal line 502 or the second metal line can be linear, zigzag, or curved.

It should be reminded that the dielectric waveguide filter 100 of the present invention is not limited to be provided with the coupling blind holes only on pairs of the th resonance unit 102 and the second resonance unit 104, actually, the dielectric waveguide filter 100 of the present invention may also be provided with the coupling blind holes on other two non-adjacent resonance units according to actual needs, for example, the coupling blind holes may be respectively provided on two non-adjacent resonance units, such as the resonance unit 101 and the resonance unit 103, the resonance unit 101 and the resonance unit 104, the resonance unit 102 and the resonance unit 105, and the coupling blind holes of the two non-adjacent resonance units are electrically connected, so that a cavity-crossing coupling structure may be introduced between the two non-adjacent resonance units, that is, the dielectric waveguide filter 100 may be provided with a plurality of cavity-crossing coupling structures to realize the cross-cavity coupling.

Preferably, the top of each resonant unit 101-105 is provided with at least tuning blind holes for tuning the resonant frequency of the resonant unit, in this embodiment, the tuning blind holes are preferably arranged at the center of the top of the resonant unit 101-105, which has better tuning effect.

The dielectric material of the dielectric waveguide filter 100 of the present invention is preferably ceramic material, although other dielectric materials may be adopted, preferably layers of th metal plating are attached to the outer surface of the dielectric waveguide filter 100, 1 layers of second metal plating are respectively provided on the inner walls of the 0 th coupling blind via 301 and the second coupling blind via 302, preferably layers of metal plating and second metal plating are preferably silver metal, although other metal materials such as copper, aluminum and the like may also be adopted, circles of th electroless plated region 310 and second electroless plated region 311 are respectively provided on the outer edges of the coupling blind via 301 and the second coupling blind via 302, the th electroless plated region 310 is used for separating the second metal plating of the th coupling blind via 301 from the th metal plating of the dielectric waveguide filter 100, and the second electroless plated region 311 is used for separating the second metal plating of the second coupling blind via 302 from the th metal plating of the dielectric waveguide filter 100.

In the embodiment shown in fig. 1, the th non-plating area 310 and the 311 second non-plating area are preferably circular, but actually, the th non-plating area 310 and the 311 second non-plating area may also be polygonal or irregular in shape, and the like, the th non-plating area 310 and the 311 second non-plating area only need to be closed in any shape, so as to separate the th metal plating layer on the surface of the dielectric waveguide filter 100 from the second metal plating layers on the inner walls of the coupling blind vias 301-302.

It should be noted that, although the structure of the dielectric waveguide filter 100 of the present invention is mainly described with reference to fig. 1, it is only a partial example of the implementation method of the present invention, and is not intended to limit the present invention.

Preferably, the coupling strength between the non-adjacent th resonant cell 102 and the second resonant cell 104 is controlled by the depth of the th coupling blind hole 301 and the second coupling blind hole 302. namely, the coupling strength between the non-adjacent th resonant cell 102 and the second resonant cell 104 is related to the depth of the th coupling blind hole 301 and the second coupling blind hole 302, and the deeper the depth of the th coupling blind hole 301 and the second coupling blind hole 302, the greater the coupling strength.

Preferably, the coupling strength of the non-adjacent th resonant cell 102 and the second resonant cell 104 is controlled by the position relationship between the bottom of the th coupling blind hole 301 and the second coupling blind hole 302 and the position relationship between the second resonant cell 102 and the second resonant cell 104 respectively, that is, the coupling strength of the non-adjacent th resonant cell 102 and the second resonant cell 104 is related to the bottom position of the th coupling blind hole 301 and the second coupling blind hole 302, the coupling strength is maximum when the bottom of the th coupling blind hole 301 and the second coupling blind hole 302 is at the middle position between the th resonant cell 102 and the second resonant cell 104, and the coupling strength is minimum when the bottom of the coupling blind hole 301 or the second coupling blind hole 302 is closer to the upper and lower end positions of the th resonant cell 102 and the second resonant cell 104.

In summary, the dielectric waveguide filter with a cross-cavity coupling structure of the present invention includes at least three sequentially connected resonant units, the dielectric waveguide filter is provided with a th coupling blind hole and a second coupling blind hole on at least pairs of non-adjacent th resonant unit and second resonant unit, and the th coupling blind hole and the second coupling blind hole are electrically connected to each other, so that the non-adjacent th resonant unit and the second resonant unit generate cross-cavity coupling and generate transmission zeros near the pass band.

The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it should be understood that various changes and modifications can be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.