CN209357886U - Special-shaped cavity three-mode resonance structure and filter comprising same - Google Patents

Abstract

The utility model discloses a special-shaped cavity multimode resonance structure and contain wave filter of this resonance structure, including cavity and apron, be provided with medium resonance piece and medium support frame in the cavity, at least one terminal surface indent or evagination of cavity, at least one terminal surface evagination or indent of medium resonance piece, medium resonance piece and medium support frame constitute three mode medium resonance pole, similar square medium resonance piece one end or arbitrary end are connected with the medium support frame respectively, the medium support frame is connected with the cavity inner wall, the medium resonance piece forms three mode resonances in the X, Y, Z axle three directions of cavity. Used the utility model discloses a cavity filter can guarantee to obtain high Q value under the less interval of resonance bar and cavity, has increased the tuning range of tuning screw rod simultaneously, has reduced the booth apart from the sensitivity to resonant frequency between cavity and the medium resonance piece simultaneously, and the production debugging of being convenient for has reduced manufacturing cost.

Description

A special-shaped cavity three-mode resonant structure and a filter containing the resonant structure

technical field

The utility model relates to a base station filter, an antenna feeder filter, a combiner and an anti-interference filter etc. used in the field of wireless communication. A special-shaped cavity three-mode resonant structure and a filter containing the special-shaped cavity three-mode resonant structure.

Background technique

With the rapid development of the fourth-generation mobile communication to the fifth-generation mobile communication, the requirements for miniaturization and high performance of communication equipment are getting higher and higher. Traditional filters are gradually replaced by single-mode dielectric filters due to their large metal cavity and general performance. Single-mode dielectric filters mainly include TE01-mode dielectric filters and TM-mode dielectric filters, TE01-mode dielectric filters and TM-mode dielectric filters. Mode dielectric filters generally use single-mode dielectric resonance. Although this resonance method can increase the Q value to a certain extent, it has the disadvantages of high manufacturing cost and large volume.

In order to solve the technical problems of high cost and large volume of single-mode dielectric filters, three-mode dielectric filters came into being. In the prior art, three-mode dielectric filters are generally classified into TE three-mode filters and TM three-mode filters. TE three-mode filter has the characteristics of complex coupling method, large size and high Q value; TM three-mode filter has the characteristics of simple coupling method, small size and low Q value. For the TE three-mode filter and the TM three-mode filter in the same frequency band, the weight, cost and volume of the TM three-mode filter are much smaller than those of the TE three-mode filter. Therefore, in the prior art, TE three-mode filters are generally used to design narrowband filters, and other types of filters generally use TM three-mode filters. Because silver is baked on the dielectric resonator block of the TM three-mode filter, after baking silver, a glassy substance is formed between the silver layer and the surface of the dielectric resonator block, resulting in a great decrease in the actual conductivity, so that the actual Q value is low. This further limits the scope of use of the TM three-mode filter. Therefore, how to obtain a small-volume, high-Q TM three-mode filter is a new direction for filter research and development.

Existing TM three-mode filters generally adopt a cubic/cube-like/spherical resonant cavity with a cubic/cube-like/spherical dielectric resonator block. The dielectric resonator block is supported by a dielectric base, and the single resonant cavity The ratio of the side size to the single side size of the dielectric resonator block is generally greater than 1.6. When the volume of the resonant cavity remains unchanged and the dielectric resonant block becomes slightly larger, or when the volume of the resonant cavity is slightly reduced and the dielectric resonant block remains unchanged, or when the volume of the resonant cavity is slightly reduced and the dielectric resonant block is slightly larger, the table 1, we can see that with the increase of the ratio of the unilateral size of the resonator cavity to the unilateral size of the dielectric resonator block, the Q value of the fundamental mode will increase with the increase of the ratio, and the Q value of the higher order mode will increase with the increase of the ratio. The ratio decreases with the increase of the ratio, the size of the dielectric resonator block decreases with the increase of the ratio, and the size of the cavity continues to increase. The Q value also decreases accordingly, and the frequency of the high-order mode increases with the increase of the ratio, and is farther and closer to the frequency of the fundamental mode.

The cavity volumes of the resonant cavities corresponding to different ratios are also different, which can be selected according to actual needs. For cavities of different sizes within the ratio range in Table 1 and the corresponding similar cubic resonators, a single cavity with a ratio above 1.6 can be selected when the filter performance is very high. Therefore, when the ratio of the unilateral size of the resonant cavity to the unilateral size of the dielectric resonant block is greater than 1.6, the Q value is proportional to the distance between the resonant cavity and the dielectric resonant block, but the disadvantage it brings is that the filter The device is too bulky.

The patent application number 2018101455572 discloses a small-volume, high-Q cavity three-mode structure, which ensures that the outer surface of the dielectric resonator block is arranged parallel to the inner surface of the cavity and the distance between the two surfaces is extremely small. It can effectively reduce the size of the filter and improve its Q value. However, this structure has the following technical problems: 1. Because the distance between the dielectric resonator block and the inner wall of the cavity is extremely small, the adjustment range of the tuning screw is limited, which is not conducive to the installation and debugging of the dielectric resonator block; The distance between the inner walls of the cavity is extremely small, so the distance between the dielectric resonator block and the cavity is highly sensitive to the resonance frequency of the single cavity, which is not conducive to the mass production of the dielectric resonator block; 3. Because the distance between the dielectric resonator block and the inner wall of the cavity The small spacing is highly sensitive to the resonant frequency of the single cavity, so the design accuracy of the dielectric resonator block and the cavity is extremely high, thus increasing the manufacturing cost.

Table 1:

Contents of the invention

Aiming at the defects of the above-mentioned prior art, the technical problem to be solved by the utility model is to provide a special-shaped cavity three-mode resonant structure and a filter containing the structure, which can reduce the overall insertion loss of the filter to meet the requirements of the cavity Filter requirements for smaller inserts and smaller volumes.

The utility model discloses a special-shaped cavity three-mode resonant structure, which comprises a cavity and a cover plate, and a dielectric resonance block and a dielectric support frame are arranged in the cavity, and is characterized in that the cavity is similar to a cube shape and at least one end surface is concave, the dielectric resonance block is similar to a cube shape and at least one end surface is convex, the dielectric support frame is respectively connected with the dielectric resonance block and the inner wall of the cavity, and the dielectric resonance block and The dielectric support frame constitutes a three-mode dielectric resonant rod, and the dielectric constant of the dielectric support frame is smaller than that of the dielectric resonator block; The ratio K between the dimensions of one side is: when conversion point 1 ≤ K ≤ conversion point 2, the higher-order mode Q value adjacent to the fundamental mode is converted into the fundamental mode Q value of the three-mode resonant structure, after conversion The resonant frequency of the fundamental mode is equal to the resonant frequency of the fundamental mode before conversion, the Q value of the fundamental mode after conversion > the Q value of the fundamental mode before conversion, and the Q value of the high-order mode adjacent to the fundamental mode after conversion < the Q value of the fundamental mode before conversion The Q value of the higher order mode adjacent to the mode; the three-mode resonant structure is provided with a coupling structure for changing the orthogonal characteristics of the degenerate three-mode electromagnetic field in the cavity; the three-mode resonant structure is provided with a coupling structure for changing the cavity Frequency tuning device for degenerate three-mode resonant frequency.

Further, the utility model discloses a special-shaped cavity three-mode resonant structure, including a cavity and a cover plate, and a dielectric resonator block and a dielectric support frame are arranged in the cavity, and the feature is that the cavity is Similar to a cube shape with at least one end surface convex, the dielectric resonance block is similar to a cube shape with at least one end surface concave, the dielectric support frame is respectively connected to the dielectric resonance block and the inner wall of the cavity, and the dielectric resonance The block and the dielectric support frame form a three-mode dielectric resonant rod, and the dielectric constant of the dielectric support frame is smaller than the dielectric constant of the dielectric resonator block; when the size of the single side of the cavity inner wall corresponds to the dielectric The ratio K between the sizes of one side of the resonant block is: when conversion point 1≤K≤transition point 2, the Q value of the higher-order mode adjacent to the fundamental mode is converted into the Q value of the fundamental mode of the three-mode resonant structure, The resonant frequency of the fundamental mode after conversion is equal to the resonant frequency of the fundamental mode before conversion, the Q value of the fundamental mode after conversion > the Q value of the fundamental mode before conversion, and the Q value of the high-order mode adjacent to the fundamental mode after conversion < the Q value before conversion The high-order mode Q value adjacent to the fundamental mode; the three-mode resonant structure is provided with a coupling structure for changing the orthogonal characteristics of the degenerate three-mode electromagnetic field in the cavity; the three-mode resonant structure is provided with a coupling structure for changing the space Frequency tuning device for degenerate three-mode resonant frequency in cavity.

In a preferred embodiment of the present utility model, the dielectric resonator block is a solid structure or a hollow structure; the hollow part of the dielectric resonator block of the hollow structure is filled with air or a nested dielectric resonator block, and the nested dielectric resonator block The volume is less than or equal to the volume of the hollow chamber.

In a preferred embodiment of the present invention, the nested dielectric resonator block is in a shape similar to a cube and at least one end surface is concave or convex.

In a preferred embodiment of the present invention, at least one end surface of the nested dielectric resonator block is provided with a film dielectric.

In a preferred embodiment of the present invention, at least one end surface of the cavity and/or at least one end surface of the dielectric resonance block is provided with a film medium.

In a preferred embodiment of the present invention, the convex end surface of the cavity or/and the concave end surface of the dielectric resonator block are provided with a film medium.

In a preferred embodiment of the present utility model, the value of the conversion point 1 and the value of the conversion point 2 will vary with the fundamental mode resonance frequency of the dielectric resonator block, the dielectric constant of the dielectric resonator block , The dielectric constant of the support frame varies.

In a preferred implementation of the present utility model, when the fundamental mode resonance frequency of the converted dielectric resonator block remains unchanged, the Q value of the three-mode resonance structure and the value of K and the dielectric The dielectric constant of the resonant block is related to the size of the dielectric resonant block.

In a preferred implementation of the present utility model, when the value of K increases from 1.0 to the maximum, the value of K has three Q value conversion points within the range of variation, and each Q value conversion point makes its fundamental model The Q value and the Q value of the high-order mode adjacent to the fundamental mode are converted, and when the Q value of the high-order mode adjacent to the fundamental mode is converted into the Q value of the fundamental mode, the Q value is increased compared with that before the conversion.

In a preferred implementation of the present utility model, in the 4 regions formed by the starting point, the end point, and three Q value conversion points of the value of K, the Q value of the fundamental model and the adjacent high order of the fundamental model The mode Q value changes gradually with the size of the cavity and the size of the dielectric resonator block, and the requirements for filters applied in different regions are different.

In a preferred embodiment of the present invention, 1.03≤value at switching point 1≤1.30, 1.03≤value at switching point 2≤1.30, value at switching point 1<value at switching point 2.

In a preferred embodiment of the present invention, the coupling structure is arranged on the dielectric resonator block, and the coupling structure includes at least two non-parallel arranged holes and/or grooves and/or cut corners and/or Chamfer.

In a preferred embodiment of the present utility model, the groove or the cut corner or the chamfer is arranged at the edge of the dielectric resonator block.

In a preferred embodiment of the present invention, the hole or groove is arranged on the end face of the dielectric resonator block, and the center line of the hole or groove is perpendicular to the end face of the dielectric resonator block on which the hole or groove is opened. The edges are parallel.

In a preferred embodiment of the present invention, the coupling structure is arranged on the cavity, and the coupling structure includes at least two non-parallel chamfers and/or bosses arranged at the inner corners of the cavity And/or a tap line/sheet arranged in the cavity and not in contact with the dielectric resonator block.

In a preferred embodiment of the present invention, the frequency tuning device includes a tuning screw/disk arranged on the cavity and/or a film arranged on the surface of the dielectric resonator block and/or arranged in the cavity The film of the wall and/or the film provided on the inner wall of the cover plate.

In a preferred embodiment of the present invention, at least one dielectric support frame is provided on at least one end face of the dielectric resonance block.

The utility model also discloses a filter with a special-shaped cavity three-mode resonant structure, which includes a cavity body, a cover plate, and an input and output structure, and at least one special-shaped cavity three-mode resonant structure is arranged in the cavity .

In a preferred embodiment of the present utility model, the special-shaped cavity three-mode resonant structure is combined with the single-mode resonant structure, the double-mode resonant structure, and the three-mode resonant structure in different forms to form filters of different volumes; The coupling between any two resonant cavities formed by the arrangement and combination of the special-shaped cavity three-mode resonant structure and the single-mode resonant cavity, double-mode resonant cavity, and three-mode resonant cavity must be the resonant rod in the two resonant cavities In the case of parallel, the coupling can be realized through the size of the window between the two resonators, and the window size is determined according to the size of the coupling amount; the functional characteristics of the filter include bandpass, bandstop, highpass, lowpass and their mutual The duplexer, multiplexer and combiner formed between them.

In a preferred embodiment of the present utility model, when the cavity three-mode resonant structure with special-shaped cavity keeps the resonant frequency unchanged, the ratio K of the three-mode Q value and the side length of the inner wall of the cavity to the side length of the dielectric resonator block 1. The dielectric constant of the dielectric resonant block is also related to the size change range of the dielectric block; the range of K value is related to different resonance frequencies, dielectric constants of the dielectric resonant rod and the support frame.

In the above technical scheme, the range of variation of the ratio K of the ratio K of the side length of the cavity inner wall to the size of the dielectric resonator block in the three-mode resonant structure of the cavity with a special shape is that when the K value increases from 1.0 to the maximum, the K value within the variation range has 3 conversion points, each conversion point converts the Q value of the fundamental mode resonance frequency and the Q value of the adjacent high-order resonance frequency, and when the adjacent high-order mode Q value is converted into the fundamental mode Q value, its Q value The value is increased than before untransformed.

Furthermore, in the four areas formed by the K value start and end points and their three Q value conversion points, the Q value of the fundamental mode and the adjacent high-order Q values gradually change with the size of the cavity and the size of the dielectric resonator block. Changes, different areas have different requirements for filters (applications in different areas are added to the manual and case).

Further, the dielectric resonator block of the present invention is a solid structure similar to a cube shape, wherein the definition of a cube-like shape is: the dielectric resonator block is a cuboid or a cube, and when the dimensions of the dielectric resonator block are equal to the X-axis, Y-axis, and Z-axis , forming a degenerate three-mode, which is coupled with other single cavity to form a passband filter; when the size differences in the three directions of the X-axis, Y-axis, and Z-axis are slightly unequal, a quasi-orthogonal three-mode is formed Resonance, if the quasi-orthogonal three-mode and other cavities can still be coupled into a passband filter, then the size is OK, if the quasi-orthogonal three-mode and other cavities cannot be coupled into a passband filter, then the size is not good; on the X axis When the dimensions of the three directions of , Y axis, and Z axis are quite different, degenerate three modes or quasi-orthogonal three modes cannot be formed, but three modes of different frequencies are formed, so that it cannot be coupled with other cavities to form a passband filter , the size does not work.

Further, at least two non-parallel coupling structures for changing the orthogonal characteristics of the degenerate three-mode electromagnetic field in the cavity are provided in the three-mode resonant structure of the cavity with different shapes. The chamfer and/or hole on the side, or include the chamfer/cut corner arranged on the edge of the cavity, or include the chamfer and/or hole arranged on the edge of the dielectric resonator block, and the edge of the cavity chamfering/cutting; or including tap lines or/pieces arranged on non-parallel planes in the cavity, the shape of the cutting corner is triangular prism or cuboid or fan-shaped, and the shape of the hole is circular, rectangular or polygon. After chamfering or drilling, under the condition of maintaining the frequency, the side length of the dielectric resonator block increases, and the Q value decreases slightly; the depth of the chamfer or hole is a through or local chamfer/local hole structure according to the required coupling amount; The size of the corner/chamfer/hole affects the amount of coupling; the coupling structure is arranged with a coupling screw along the direction perpendicular or parallel to the chamfer and/or in the direction parallel to the hole, the material of the coupling screw is metal, or the material of the coupling screw It is metal and the metal surface is electroplated with copper or silver, or the material of the coupling screw is a medium, or the material of the coupling screw is a medium with metallization on the surface; the shape of the coupling screw is a metal rod, a dielectric rod, a metal disc, a dielectric disc, and a metal rod Any one of metal plate, metal rod with medium plate, medium rod with metal plate, and medium rod with medium plate.

Further, degenerate three modes in the X-axis, Y-axis and Z-axis directions are formed in the three-mode resonant structure of the cavity, and the resonant frequency of the degenerate three modes in the X-axis direction passes through the X-axis corresponding to the cavity. Install a tuning screw or a tuning disc to change the distance or change the capacitance on one side or two sides of the axis where the field strength is concentrated; the resonant frequency in the Y-axis direction can be achieved by adding a tuning screw or a tuning plate to the place where the field strength is concentrated on one side or two sides of the Y-axis corresponding to the cavity Install a tuning screw or a tuning disc to change the distance or change the capacitance; the resonance frequency in the Z-axis direction can be changed by installing a tuning screw or a tuning disc on the side of the Z-axis corresponding to the cavity or where the field strength is concentrated on both sides It can also be achieved by changing the distance or changing the capacitance; in addition, it can also be achieved by pasting dielectric constant films of different shapes and thicknesses on the surface of the dielectric resonator block, the inner wall of the cavity or the inner wall of the cover plate, and the bottom of the tuning screw. The film material can be ceramic dielectric and ferroelectric material. The frequency is adjusted by changing the dielectric constant; the material of the tuning screw or tuning disc is metal, or the material of the tuning screw or tuning disc is metal and the metal surface is electroplated with copper or silver, or the material of the tuning screw or tuning disc is the dielectric, or The material of the tuning screw or the tuning plate is a medium with metallization on the surface; the shape of the tuning screw is metal rod, medium rod, metal plate, medium plate, metal rod with metal plate, metal rod with medium plate, medium rod with metal plate, medium The rod is matched with any one of the dielectric discs; similar to the cube dielectric resonator block, the ratio of the dielectric material can be adjusted to control the frequency temperature coefficient of the dielectric block, and compensation is made according to the frequency offset change of the filter at different temperatures; the dielectric When the support frame is fixed to the inner wall of the cavity, in order to avoid the stress generated by the cavity and the dielectric material in the environment of sudden temperature changes, an elastic body is used to transition between them to buffer the reliability risk caused by the expansion coefficient of the material.

Further, the cavity three-mode resonant structure with special-shaped cavity is composed of a cavity, a dielectric resonator block and a support frame; when the cavity is similar to a cube, a single cube-like dielectric resonator block and a dielectric support frame are installed on any axis of the cavity direction, the center of the dielectric resonator block coincides with or is close to the center of the cavity. Approximate air medium support frame and similar cube medium blocks can be supported on any one side, or on six sides, or on different combinations of two, three, four and five sides. The medium support frame is a single or multiple medium support frames, and one or more support frames can be installed on different surfaces according to the needs. The support frame whose dielectric constant is greater than that of air and smaller than that of the dielectric resonance block is supported on any one side of a similar cube dielectric block, or on six sides, or on different two, three, four and five sides. Combined support, the surface without the support frame is air, the air surface and the dielectric support frame can be combined arbitrarily, the dielectric support frame of each surface is a single or multiple dielectric support frames, or it is composed of multiple layers of dielectric materials with different dielectric constants Composite permittivity support frame, any combination of single-layer and multi-layer dielectric material support frames and similar cube dielectric blocks, one or more support frames can be installed on different sides according to needs, and the surface of the support frame is installed. In order to maintain the three-mode For frequency and Q value, the size of the dielectric support frame corresponding to the axial direction of the dielectric resonator block needs to be slightly reduced; the single-sided support combination is to support any surface of the dielectric resonator block, especially the bottom surface or load-bearing surface in the vertical direction; 2 pieces The support combination of surfaces includes parallel surfaces, such as top and bottom, front and back, left and right surfaces; it also includes non-parallel surfaces, such as top and front, top and back, top and left, top and right; the support combination of three faces includes: Three mutually perpendicular faces, or two planar faces and one non-parallel face; the support combination of 4 faces includes: two pairs of parallel faces or a pair of parallel faces and the other two non-parallel faces; 5 The support combination of surfaces includes: the support structure of any surface except the front/rear/left/right/above/below; the support combination of 6 surfaces includes: the support structure of all surfaces in the front/rear/left/right/above/below.

Further, any end of a cube-like dielectric resonator block and the dielectric support frame are connected by means of crimping, bonding or burning; it is connected on one surface or a combination of different surfaces, and the multi-layer dielectric support frame is connected by bonding. Connecting, burning, crimping, etc., the dielectric support frame and the inner wall of the cavity are connected by bonding, crimping, welding, burning, screws, etc.; The radio frequency path formed by coupling will cause loss and generate heat. The dielectric resonator block is fully connected with the dielectric support frame and the metal inner wall, so that the heat is introduced into the cavity for heat dissipation.

Further, a cube-like dielectric resonator block has a single dielectric constant or a composite dielectric constant. The composite dielectric constant is composed of two or more different dielectric constants. The dielectric resonator block composed of composite dielectric constants has different dielectric constants. Materials can be combined up and down, left and right, asymmetrical, nested, etc. When the dielectric resonator block is nested with different dielectric constants, one layer or multiple layers of dielectric materials with different dielectric constants can be nested, and the composite dielectric constant The dielectric resonator block needs to conform to the change law of the aforementioned Q value conversion point. When performing edge-cut coupling between the three modes of the resonant rod of the dielectric block, in order to maintain the required frequency, the corresponding side lengths of the two adjacent faces of the cut-edge need to be adjusted in parallel. The dielectric resonance block is made of ceramic or dielectric material, and dielectric sheets with different thicknesses and different dielectric constants can be added on the surface of the dielectric resonance block.

Further, the dielectric constant of the dielectric support frame is similar to the dielectric constant of air, or the dielectric constant of the support frame is greater than the dielectric constant of air and smaller than the dielectric constant of the dielectric resonator block, and the surface area of the dielectric support frame is less than or equal to that of a similar cube dielectric resonator block. The surface area, the dielectric support frame is in the shape of cylinder, cube and cuboid. The medium support frame is a solid structure or a hollow structure. The medium support frame of the hollow structure is single hole or porous. The shape of the hole is circular, square, polygonal and arc-shaped. The material of the medium support frame includes air, plastic, ceramics, and medium; The dielectric support frame is connected with the dielectric resonator block. When the dielectric constant of the dielectric support frame is similar to the dielectric constant of air, the dielectric support frame has no effect on the three-mode resonance frequency; the dielectric constant of the dielectric support frame is greater than that of air but smaller than that of the dielectric resonator block. When constant, in order to maintain the original three-mode frequency, the dimension of the dielectric support frame corresponding to the axial direction of the dielectric resonator block is slightly reduced; similar to the air permittivity support frame and the support frame larger than air but smaller than the dielectric resonator block, they can be combined and installed in the medium The resonant block has different directions and different corresponding surfaces. When the above two support frames with different dielectric constants are used in combination, the axial dimension of the resonant block corresponding to the air support frame is slightly reduced on the original basis.

Furthermore, the shape of the cavity is similar to a cube. In order to realize the coupling between the three modes, without changing the size of the dielectric resonator block similar to a cube, it is also possible to cut edges on any adjacent two sides of the cavity to realize the three modes. The coupling between them, the size of the cutting edge is related to the required coupling amount; the three-mode coupling can also be achieved by the coupling between the two modes through the cutting edge of a similar cube, and the remaining coupling is achieved through the two adjacent edge cutting angles of the cavity. Realize that the wall cannot be broken when the adjacent edge of the cavity is cut, and the cut surface must be completely sealed with the cavity. The cavity material is metal or non-metal, and the metal and non-metal surfaces are electroplated with copper or silver. When the cavity is made of non-metal materials, the inner wall of the cavity must be electroplated with conductive materials such as silver or copper, such as plastics and composite materials. The surface is electroplated with copper or silver.

Further, the cavity three-mode resonant structure with different shapes is combined with the single-mode resonant structure, the double-mode resonant structure and the three-mode resonant structure in different forms to form filters of different volumes; the special-shaped cavity three-mode resonant structure and The coupling between any two resonant cavities formed by the arrangement and combination of single-mode resonant cavities, double-mode resonant cavities, and triple-mode resonant cavities must be in the case that the resonant rods in the two resonant cavities are parallel to pass through the two resonant cavities. The size of the window between two resonators realizes coupling, and the size of the window is determined according to the size of the coupling; the functional characteristics of the filter include bandpass, bandstop, highpass, lowpass, and the duplexer, multiplexer, and duplexer formed between them. Combiner.

The dielectric constant of the cube-like dielectric resonant block of the utility model is greater than that of the support frame, and when the ratio of the unilateral size of the inner wall of the cavity to the unilateral size of the dielectric resonant block is between 1.03-1.30, the high-order mode Q The value is reversed into the Q value of the fundamental mode. The Q value of the fundamental mode of the three-mode dielectric increases and the Q value of the high-order mode decreases. Compared with the traditional single-mode and three-mode dielectric filters with the same volume and frequency, the Q value increases by more than 30%. According to this The combination of three-mode structure and different types of single cavity, such as the combination of three-mode structure plus cavity single-mode, three-mode and TM mode, three-mode and TE single-mode, the more the number of three-mode is used in the filter, the filter The smaller the volume of the device, the smaller the insertion loss; the cavity three-mode resonant structure with special-shaped cavity can generate three-mode resonance in the directions of X, Y, and Z axes respectively, and when the three-mode resonance is generated in the directions of X, Y, and Z axes .

When the ratio of the side length of the inner wall of the cavity to the corresponding side length of the dielectric resonator block is 1.0 to the conversion point 1 of the Q value conversion, the cavity is a pure medium Q value when the ratio is 1.0, and when the cavity size increases, the Q value is in a pure medium. The Q value of the higher-order mode is greater than the Q value of the fundamental mode. When the ratio increases to the conversion point 1, the Q value of the original higher-order mode approximates the Q value of the new fundamental mode.

After entering transition point 1, the Q value of the fundamental mode is greater than the Q value of the higher order mode while keeping the resonance frequency of the fundamental mode unchanged. As the ratio increases, the Q value of the fundamental mode will also increase due to the increase in the size of the dielectric block and the cavity, and the Q value of the higher-order mode will also increase at the same time. The value reaches the highest value, between the fundamental mode Q value conversion conversion point 1 and the fundamental mode Q value conversion conversion point 2, the frequency of the high-order mode is far from the frequency of the fundamental mode with the ratio of the cavity to the dielectric resonant block at the conversion point 1 to The change of conversion point 2 will be far and near.

After entering transition point 2, the Q value of the fundamental mode is smaller than the Q value of the higher order mode. With the increase of the ratio, the size of the dielectric resonator block is decreasing, the size of the cavity is increasing, and the Q value of the fundamental mode will continue to increase. , when the ratio is close to transition point 3, the Q value of the fundamental mode is close to the Q value at transition point 2.

After the ratio enters the conversion point 3, the Q value of the fundamental mode will increase with the increase of the ratio, and the Q value of the high-order mode will decrease with the increase of the ratio, and the size of the dielectric resonant block will decrease with the increase of the ratio. The size of the cavity continues to increase. When the size of the cavity is close to 3/4 wavelength, the Q value of the fundamental mode also decreases due to the continuous reduction of the size of the dielectric resonator block. The frequency is far and near. The specific ratio of the conversion point is related to the dielectric constant and frequency of the dielectric resonant block and whether the dielectric resonant block is single or composite.

The side length of the inner wall of the cavity and the side length of the dielectric resonator block can be equal or unequal in the three directions of X, Y and Z axes. Cavity and cube-like dielectric resonator blocks can form three modes when the X-axis, Y-axis, and Z-axis are equal in size; the size differences in the three directions of the X-axis, Y-axis, and Z-axis can also be slightly unequal. When the unilateral size of the cavity in one of the Y and Z axis directions and the corresponding dielectric resonant block is different from the unilateral size of the other two directions, or any one of the symmetrical unilateral dimensions of the cavity and the dielectric resonant block is different from the other two When the unilateral size of the direction is different, the frequency of one of the three modes will change from the frequency of the other two modes. The greater the size difference, the greater the frequency difference between one mode and the other two modes. When When the size of one direction is larger than the size of the other two directions, the frequency will drop on the original basis. When the size of one direction is smaller than the size of the other two directions, the frequency will rise on the original basis, gradually changing from three modes to It is a double-mode or single-mode; if the three axial dimensions of the cavity and the resonant block are too different; when the symmetrical unilateral dimensions in the three directions of the X, Y, and Z axes are different, the frequencies of the three modes in the three modes will be different. When the side lengths in the three directions differ greatly, the fundamental mode is single mode. In the case where the side lengths in the three directions are not much different, the frequency difference is not large, although the frequency will be There are changes, but it is still possible to maintain the tri-mode status through the tuning device.

The coupling between the three modes can adopt at least two non-parallel coupling structures for changing the orthogonal characteristics of the degenerate three-mode electromagnetic field in the cavity in the three-mode resonant structure of the cavity with different shapes. The coupling structure includes cut corners and/or holes arranged beside the edges of the dielectric resonator block, or includes chamfers/cut corners arranged beside the edges of the cavity, or includes cut corners and/or holes arranged beside the edges of the dielectric resonator block Or hole, and the chamfer/cut corner next to the edge of the cavity or include a tap line or/sheet arranged on a non-parallel plane in the cavity, and the shape of the cut corner is a triangular prism or a cuboid or a fan-shaped body , the shape of the hole is circular, rectangular or polygonal. After corner cutting or drilling, the side length of the dielectric resonator block increases while the frequency is maintained, and the Q value decreases slightly. The depth of the chamfer or the hole is a through or partial chamfer/partial hole structure according to the size of the required coupling amount, and the size of the chamfer/chamfer/hole affects the size of the coupling amount. The coupling structure is arranged with coupling screws in a direction perpendicular to or parallel to the cutting angle and/or in a direction parallel to the holes, and the material of the coupling screws is metal, or the material of the coupling screws is metal and the metal surface is electroplated with copper or electroplated with silver, or The material of the coupling screw is medium, or the material of the coupling screw is a medium with metallization on the surface; the shape of the coupling screw is metal rod, medium rod, metal disc, medium disc, metal rod with metal disc, metal rod with dielectric disc, and dielectric rod Any one of metal plate and medium rod with medium plate.

The resonant frequency of the three-mode in the X-axis direction is realized by adding a tuning screw or a tuning disc to change the distance or changing the capacitance on one side of the X-axis corresponding to the cavity or where the field strength is concentrated on both sides; the resonant frequency in the Y-axis direction can be It can be realized by adding a tuning screw or a tuning disc to change the distance or change the capacitance on one or both sides of the Y-axis corresponding to the cavity where the field intensity is concentrated; Install tuning screws or tuning discs on one or both sides where the field strength is concentrated to change the distance or change the capacitance.

Dielectric resonator Q value conversion three-mode structure and single-mode resonant cavity, dual-mode resonant cavity or three-mode resonant cavity are arranged and combined in different forms to form filters of different sizes required; the functional characteristics of the filter include but are not limited to Band-pass, band-stop, high-pass, low-pass, and duplexers and multiplexers formed between them; any two resonances formed by combination queues between single-mode resonators, double-mode resonators, and three-mode resonators The coupling between cavities is based on the fact that the two resonant structures are parallel and the coupling between the two resonant cavities is achieved through the size of the window.

The beneficial effects of the utility model are: the utility model has a simple structure and is easy to use, and the ratio of the unilateral size of the metal cavity inner wall of the dielectric three-mode to the unilateral size of the dielectric resonance block is set between 1.01-1.30, so that The cooperation between the resonant rod and the cavity forms a three-mode structure and at the same time realizes the inversion of specific parameters, thereby ensuring a high Q value at a small distance between the resonant rod and the cavity; further, the utility model discloses a Compared with the filter of the special-shaped three-mode resonant structure, the utility model reduces the insertion loss by more than 30% under the premise of the same frequency and the same volume as compared with the traditional three-mode filter. The dielectric resonator frequency conversion three-mode structure composed of the cube-like dielectric resonator block, the dielectric support frame and the cavity cover plate of the utility model is mutually orthogonal and perpendicular to each other in the x-axis, y-axis and z-axis directions of the cavity, forming Three resonant modes that do not interfere with each other are created, and the high-order mode frequency is converted into a high-Q fundamental mode frequency, forming coupling between the three magnetic fields, and the different bandwidth requirements of the filter are met by adjusting the strength of the coupling. In a typical 1800MHz frequency filter, when two filters with this special-shaped cavity three-mode resonant structure are used, it is equivalent to the volume of six single cavities in the original cavity, and the volume can be reduced on the basis of the original cavity filter. 40%, the insertion loss can also be reduced by about 30%. Since the volume is greatly reduced, and the processing hours and plating area will be reduced accordingly, although the dielectric resonator block is used, the cost is equivalent to the cavity. If the material cost of the dielectric resonator block can be The cost advantage of this design will be more obvious, and when there are many filter cavities, even three three-mode structures can be used, and the volume and performance will be more obvious; further, the utility model can be used without On the premise of greatly reducing the Q value of the single cavity, by changing the dielectric resonator block and/or the cavity into a structure (setting a special-shaped end face) on the basis of the three-mode resonant structure, the tuning range of the tuning screw is increased, and the cavity is reduced. The small distance between the dielectric resonance block and the sensitivity of the resonance frequency facilitates production debugging and reduces production costs.

Description of drawings

Fig. 1 is a structural schematic diagram of a special-shaped cavity three-mode resonant structure of the present invention. Wherein, the dielectric resonance block is concave inside, and the cavity is convex outside.

Fig. 2 is a structural schematic diagram of a special-shaped cavity three-mode resonant structure of the present invention. Wherein, the dielectric resonance block is concave inside, the cavity is convex outside, and the resonance screws are all located on the cover plate.

Fig. 3 is a structural bottom view of a special-shaped cavity three-mode resonant structure of the present invention. Wherein, the dielectric resonance block is concave inside, the cavity is convex outside, and the resonance screws are all located on the cover plate.

Fig. 4 is a structural schematic diagram of a special-shaped cavity three-mode resonant structure of the present invention. Wherein, the dielectric resonance block is concave inside, the cavity is convex outside, and the resonance screw is respectively located on the cover plate and the cavity.

In the figure: 1-cavity, 2-dielectric resonance block, 3-dielectric support frame, 5-groove, B1-first medium support frame, B2-second medium support frame, B3-third medium support frame, B4- Fourth medium support frame, B5-fifth medium support frame, B6-sixth medium support frame.

Detailed ways

The special-shaped cavity multimode resonant structure described in the following embodiments includes:

The cavity is a special-shaped concave, while the dielectric resonance block is a special-shaped convex, and the dielectric support frame;

The cavity is a special-shaped convex, while the dielectric resonance block is a special-shaped concave, and the dielectric support frame;

The medium support frame is made to match the special-shaped structure, and the number can be one or more. The shape can be a regular shape, such as a solid/hollow cylinder, a solid/hollow square column, etc., or an irregular shape; or it can be composed of multiple columns.

In order to ensure multi-mode and corresponding frequency, the special-shaped structure cannot be infinitely concave or convex, and there are certain restrictions. An example is given below to illustrate, and others can be obtained similarly.

Eg: Single cavity 26mm×26mm×26mm, dielectric support frame is Er9.8, Q×f is 100000, outer diameter is 15mm, inner diameter is 9.7mm; dielectric resonance rod is Er43, Q×f is 43000,

Obviously, the longest side length 25.97 of the dielectric resonator block is close to the side length 26mm of the cavity, so the maximum concave size is 1.5mm.

The utility model will be further described in detail below in conjunction with the accompanying drawings and specific embodiments to facilitate a clear understanding of the utility model, but they do not limit the utility model.

As shown in Figure 1-3, the utility model is a special-shaped cavity three-mode resonant structure, including a cavity 1, a dielectric resonator block 2 and a dielectric support frame 3 are arranged in the cavity 1, and the cavity 1 It is similar to a cube and has one or more mutually non-parallel end faces protruding outward. The protruding part of the cavity 1 is formed by partially digging grooves 5 on one or more mutually non-parallel end faces of the inner wall of the cavity. The dielectric resonator block 2 is formed by one or more non-parallel end faces of a cube-like medium through local digging 5. The six end surfaces of the dielectric resonator block 2 are respectively connected to the inner wall of the cavity 1 through six dielectric support frames 3; three tuning screws are arranged on the cover plate, and the three tuning screws are arranged in parallel to each other.

As shown in Figure 4, a special-shaped cavity three-mode resonant structure of the present invention includes a cavity 1, a dielectric resonator block 2 and a dielectric support frame 3 are arranged in the cavity 1, and the cavity 1 is similar to A cube with one or more mutually non-parallel end faces protruding outward, the protruding part of the cavity 1 is formed by partially digging grooves 5 on one or more mutually non-parallel end faces of the inner wall of the cavity, and the dielectric resonator block 2 is formed by One or more non-parallel end faces of a cube-like medium are formed by partial digging 5 . The six end surfaces of the dielectric resonator block 2 are respectively connected to the inner wall of the cavity 1 through six dielectric support frames 3; tuning screws are arranged on the cover plate and the cavity, and the three tuning screws are arranged perpendicular to each other in pairs.

All the above embodiments are only preferred embodiments of the present invention, and do not constitute a limitation thereto, especially the shape and quantity of the medium support frame.

The three mutually perpendicular edge directions in the dielectric resonator block 2 are respectively defined as the X direction, the Y direction and the Z direction, and the three directions are relative position directions, which are not uniquely determined. The dielectric resonator block 2 is in X, Y, Z The dielectric support frames in the three directions and the corresponding surfaces respectively form the X-axis dielectric resonance rod, the Y-axis dielectric resonance rod and the Z-axis dielectric resonance rod, and the X-axis dielectric resonance rod, the Y-axis dielectric resonance rod and the Z-axis dielectric resonance rod The interior of the cavity cooperates to form three degenerate modes; the resonant frequency in the X-axis direction can be achieved by installing a tuning screw on the side wall corresponding to the metal cavity to change the distance or capacitance; the resonant frequency in the Y-axis direction can be achieved by The side wall corresponding to the metal cavity is equipped with a tuning screw to change the distance or capacitance; the resonant frequency in the Z-axis direction can be achieved by installing a tuning screw on the side wall corresponding to the metal cavity to change the distance or capacitance.

The radio frequency signal will generate loss after the three-mode resonance, and the three degenerate modes in the X, Y, and Z directions will generate heat during operation, which can be fully contacted by the dielectric resonator block and multiple dielectric support frames with the metal cavity wall to form heat conduction, so that Its filter can work stably for a long time.

There is a coupling structure 5 between the three degenerate modes, specifically: the dielectric resonator block 2 is provided with a first plane j1 for coupling the resonance modes in the X direction and the Y direction, and a plane j1 for coupling the resonance modes in the Y direction and the Z direction. The second plane j2, the third plane j3 used to couple the resonant modes in the X direction and the Z direction, the first plane j1, the second plane j2 and the third plane j3 are perpendicular to each other in pairs, the first plane j1 and the Z The edges arranged in the X direction are parallel, the second plane j2 is parallel to the edges arranged in the X direction, and the third plane is parallel to the edges arranged in the Y direction. That is, among the three degenerate modes, the coupling between the degenerate modes in the X direction and the degenerate modes in the Y direction is formed by the crossing of the X and Y planes of the dielectric resonator block A to form the first plane after cutting off part of the corners along the Z-axis direction Formed by j1; the coupling between the degenerate modes in the X direction and the degenerate modes in the Z direction is formed by the second plane j2 after cutting off part of the corners along the X-axis direction from the Y and Z planes of the dielectric resonator block; The coupling between the degenerate modes in the Z direction and the degenerate modes in the Z direction is formed by the third plane j3 after the Z and X planes of the dielectric resonator block intersect to form corners along the Y-axis direction after part of the corners are cut off. The larger the area of the coupling surface, the greater the coupling amount, and vice versa, the smaller the coupling amount. The three degenerate modes formed by the dielectric resonant block can form a transmission zero point through cross-coupling. If the resonance mode in the X direction, the coupling between the resonance modes in the Y direction, the coupling between the resonance mode in the Y direction and the resonance mode in the Z direction If the main coupling is used, then the coupling between the X-direction resonant mode and the Z-direction resonant mode is cross-coupling.

In the above scheme, one or more first planes j1 can be set according to the actual coupling amount. When multiple first planes j1 are set, the multiple first planes j1 are arranged in parallel; the second plane j2 can be set One or more, when multiple second planes j2 are set, multiple second planes j2 are arranged in parallel; the third plane j3 can be set one or more, when multiple third coupling surfaces j3 are set, multiple The third planes j3 are arranged in parallel.

In the above scheme, the dielectric resonator block 2 is directly formed by at least one end surface of a cube-like medium with approximate side lengths or a cube medium with equal side lengths through convex or integral or local film growth on the surface, or a cube-like or side-like cube with approximate side lengths. At least one end face of cube media with equal lengths is composed of whole or partial growth film media after being convex, and the material of the dielectric resonant block is ceramic or dielectric.

Preferably, the dielectric resonator block 2 is directly formed from at least one end surface of a similar cube or a cube medium with an approximate side length through indentation, or at least one end surface of a cube-like medium with an approximate side length or a cube medium with an equal side length The material of the dielectric resonator block 2 is ceramic or dielectric by integrally or partially growing thin-film dielectric after concave.

In the above solution, one or more dielectric support frames 3 can be designed. When multiple dielectric support frames 3 are provided, the multiple dielectric support frames 3 are respectively installed between each surface of the dielectric resonator block 2 and the inner wall of the cavity. Figure 1 of the embodiment of the utility model shows six dielectric support frames 3, the dielectric resonance block is located at the center of the six dielectric support frames, and the six surfaces A1-A6 of the dielectric resonance block 2 are respectively connected to the six dielectric support frames 3 , specifically, the six medium support frames 3 are the first medium support frame B1, the second medium support frame B2, the third medium support frame B3, the fourth medium support frame B4, the fifth medium support frame B5 and the sixth medium support frame Support frame B6, one end surface A1 of the dielectric resonance block 3 along the X direction is connected with the first dielectric support frame B1, and the other end surface A2 is connected with the second dielectric support frame B2 to form an X-axis dielectric resonance rod; the dielectric resonance block 2 is along One end surface A3 in the Y direction is connected to the third dielectric support frame B3, and the other end surface A4 is connected to the fourth dielectric support frame B4 to form a Y-axis dielectric resonance rod; one end surface A5 of the dielectric resonance block 2 along the Z direction is connected to the fifth dielectric support The frame B5 is connected, and the other end surface A6 is connected to the sixth medium support frame B6.

The shapes of the plurality of medium supporting frames 3 include but are not limited to circular, elliptical, square and irregular shapes in which the inner wall of the cavity closely matches the end surface of the corresponding medium. The material of the medium support frame 3 includes but not limited to plastic, medium, and air, and the medium support frame is a solid structure or a hollow structure in the middle. The connection between the dielectric resonator block 2 and the dielectric support frame 3 includes, but is not limited to, gluing and crimping. The connection between the medium support frame and the inner wall of the cavity includes, but is not limited to, gluing, crimping, screw fastening, and welding. The shape of the cavity is cube-like or cubic, and the cavity is made of metal material, or the cavity is made of metal material and the inner wall of the metal material is plated with silver or copper, or the cavity is made of non-metallic material with a metal layer on the surface. In order to reduce the change of frequency at different ambient temperatures, the frequency deviation can be controlled by adjusting the material ratio of the dielectric resonance block according to different temperature deviations. In addition, in order to ensure its structural reliability, the dielectric support frame is made of elastic materials such as plastic. Make this structure counteract the effects of thermal expansion and cold expansion under different environments.

The shape of the medium support frame of the solid structure is a solid structure or a tubular body structure through the middle or a combination of multiple discrete solid columns;

The material of the medium supporting frame of the solid structure is plastic, ceramics or medium, and the material of the medium supporting frame of the non-solid structure is air.

The two ends of the dielectric resonance block along the X direction are connected to the first dielectric support frame and the second dielectric support frame by gluing or crimping; the two ends of the dielectric resonance block along the Y direction are connected to the third dielectric support The frame and the fourth dielectric support frame are connected by gluing or crimping; the two ends of the dielectric resonance block along the Z direction are connected to the fifth dielectric support frame and the sixth dielectric support frame by gluing or crimping connect.

Further, the total resonant rod formed by the resonant rods in the three directions of X, Y and Z and the cavity form a three-mode resonant cavity structure; the shape of the cavity is a cube or an approximate cube, and the cavity is made of a metal material, Or it is made of a metal material and the inner wall of the metal material is plated with silver or copper, or the cavity is made of a non-metal material with a metal layer on the surface.

Further, the resonant rods in the three directions of X, Y and Z form the connection between the total resonant rod and the inner wall of the cavity by gluing, crimping, screw fastening or welding; the resonant rods in the three directions of X, Y and Z The rods form the total resonance rod with compensation for frequency changes with temperature; the resonance rods in the three directions of X, Y and Z form the dielectric support frame of the total resonance rod, and the material with certain elasticity or the shape of the elastic structure is used to make the structure in different To counteract the impact of thermal expansion and contraction in the environment, the elastic material of the medium support frame is plastic, medium, composite material and aluminum oxide.

In the above scheme, the resonant frequency of the degenerate three modes in the X-axis direction is realized by adding a tuning screw or a tuning plate on one or both sides of the X-axis corresponding to the cavity to change the distance or change the capacitance; in the Y-axis direction The resonant frequency can be realized by adding a tuning screw or a tuning plate on one side or both sides of the Y-axis corresponding to the cavity to change the distance or change the capacitance; the resonant frequency in the Z-axis direction can be achieved by adding a tuning screw or a tuning plate on one side or both sides of the Y-axis corresponding to the cavity. Install tuning screws or tuning discs on both sides to change the distance or change the capacitance to achieve;

The material of the tuning screw or the tuning disc is metal, or the material of the tuning screw or the tuning disc is metal and the metal surface is electroplated with copper or silver, or the material of the tuning screw or the tuning disc is a medium, or the material of the tuning screw or the tuning disc is It is the medium for surface metallization;

The shape of the tuning screw is any one of a metal rod, a dielectric rod, a metal disc, a media disc, a metal rod with a metal disc, a metal rod with a media disc, a media rod with a metal disc, and a media rod with a media disc.

In the above solution, at least two non-parallel coupling structures for destroying the orthogonality of the degenerate multi-mode electromagnetic field in the cavity are provided on the shaped dielectric resonator block and/or at the non-corresponding position of the cavity, and the coupling structures include The cut corners and holes next to the edges of the special-shaped dielectric resonator block and/or the cut corners beside the edges of the cavity are in the shape of a triangular prism or similar to a cube or sector. Among the three degenerate modes, the coupling between the degenerate mode in the X direction and the degenerate mode in the Y direction is formed by the crossing of the X and Y planes of the dielectric resonator block to form the first plane after cutting off some of the corners along the Z-axis direction Formed, on the edge formed by the crossing of the X and Y planes of the cavity, the coupling screw is arranged parallel or vertically to realize the fine adjustment of the coupling amount; the coupling between the degenerate mode in the Y direction and the degenerate mode in the Z direction is controlled by the dielectric resonator block The Y and Z planes intersect to form edges and corners, and the second plane is formed after cutting off part of the edges and corners along the X-axis direction. On the edges formed by the intersection of Y and Z planes in the cavity, the coupling screw is set parallel or vertical to realize fine adjustment of the coupling amount; Z direction The coupling between the degenerate mode and the degenerate mode in the X direction is formed by the intersection of the Z and X planes of the dielectric resonator block to form corners. The third plane after cutting off part of the corners along the Y-axis direction is formed by the intersection of the Z and X planes of the cavity. The coupling screw is set parallel or vertically on the edge to realize the fine adjustment of the coupling amount;

The material of the coupling screw is metal, or the material of the coupling screw is metal and the metal surface is electroplated with copper or silver, or the material of the coupling screw is a medium, or the material of the coupling screw is a surface metallized medium;

The shape of the coupling screw is any one of a metal rod, a dielectric rod, a metal disk, a dielectric disk, a metal rod with a metal disk, a metal rod with a dielectric disk, a dielectric rod with a metal disk, or a dielectric rod with a dielectric disk.

Further, the radio frequency signal forms a radio frequency path through the coupling between the resonant mode in the X direction and the resonant mode in the Y direction, and the coupling between the resonant mode in the Y direction and the resonant mode in the Z direction, and generates loss and heat. The six dielectric support frames are fully connected with the inner wall of the cavity to form heat conduction and dissipate heat.

Furthermore, the multi-mode shaped resonant structure with small spacing and different forms of single-mode resonant cavities, dual-mode resonant cavities, and three-mode resonant cavities are combined in different forms to form filters of different volumes;

The functional characteristics of the filter include bandpass, bandstop, highpass, lowpass and the combiner formed between them;

The coupling between any two resonant cavities formed by the arrangement and combination of the three-mode dielectric resonant cavity structure and the single-mode resonant cavity, double-mode resonant cavity, and three-mode resonant cavity must be that the resonant rods in the two resonant cavities are parallel In the case of , the coupling can be achieved through the size of the window between the two resonators.

It should be understood that, the above are only specific embodiments of the present utility model, but the scope of protection of the present utility model is not limited thereto, and any person familiar with the art can easily think of All changes or replacements should fall within the protection scope of the present utility model. The content not described in detail in this specification belongs to the prior art known to those skilled in the art.

Claims (28)

1. A special-shaped cavity three-mode resonant structure, including a cavity and a cover plate, a dielectric resonator block and a dielectric support frame are arranged in the cavity, and it is characterized in that: the cavity is similar to a cube shape and at least one The end face is concave, the dielectric resonant block is similar to a cube shape and at least one end face is convex, the dielectric support frame is respectively connected with the dielectric resonant block and the inner wall of the cavity, and the dielectric resonant block is connected with the dielectric support frame to form a three-mode dielectric resonant rod, the dielectric constant of the dielectric support frame is smaller than the dielectric constant of the dielectric resonant block; When the ratio K between the size of one side of the inner wall of the cavity and the size of the corresponding side of the dielectric resonator block is: conversion point 1 ≤ K ≤ conversion point 2, the higher-order mode adjacent to the fundamental mode The Q value is converted to the fundamental mode Q value of the three-mode resonant structure, the fundamental mode resonance frequency after conversion is equal to the fundamental mode resonance frequency before conversion, the fundamental mode Q value after conversion is greater than the fundamental mode Q value before conversion, and the converted and The Q value of the higher-order mode adjacent to the fundamental mode < the Q value of the higher-order mode adjacent to the fundamental mode before conversion; The three-mode resonant structure is provided with a coupling structure for changing the orthogonal characteristics of the degenerate three-mode electromagnetic field in the cavity; The three-mode resonant structure is provided with a frequency tuning device for changing the degenerate three-mode resonant frequency in the cavity. 2. A special-shaped cavity three-mode resonant structure, including a cavity and a cover plate, a dielectric resonator block and a dielectric support frame are arranged in the cavity, and it is characterized in that: the cavity is similar to a cube shape and at least one The end surface is convex, the dielectric resonance block is similar to a cube shape and at least one end surface is concave, the dielectric support frame is respectively connected with the dielectric resonance block and the inner wall of the cavity, and the dielectric resonance block is connected with the dielectric support frame to form a three-mode dielectric resonant rod, the dielectric constant of the dielectric support frame is smaller than the dielectric constant of the dielectric resonant block; When the ratio K between the size of one side of the inner wall of the cavity and the size of the corresponding side of the dielectric resonator block is: conversion point 1 ≤ K ≤ conversion point 2, the higher-order mode adjacent to the fundamental mode The Q value is converted to the fundamental mode Q value of the three-mode resonant structure, the fundamental mode resonance frequency after conversion is equal to the fundamental mode resonance frequency before conversion, the fundamental mode Q value after conversion>the fundamental mode Q value before conversion, after conversion The Q value of the higher-order mode adjacent to the fundamental mode < the Q value of the higher-order mode adjacent to the fundamental mode before conversion; The three-mode resonant structure is provided with a coupling structure for changing the orthogonal characteristics of the degenerate three-mode electromagnetic field in the cavity; The three-mode resonant structure is provided with a frequency tuning device for changing the degenerate three-mode resonant frequency in the cavity. 3. according to claim 1 or 2 described in a kind of special-shaped cavity three-mode resonance structure, it is characterized in that: described dielectric resonance block is solid structure or hollow structure; The hollow part of the dielectric resonance block of hollow structure is filled with Air or nested dielectric resonant block, the volume of the nested dielectric resonant block is less than or equal to the volume of the hollow chamber. 4. A special-shaped cavity three-mode resonant structure according to claim 3, characterized in that: the nested dielectric resonator block is in the shape of a cube and at least one end surface is concave or convex. 5. A special-shaped cavity three-mode resonant structure according to claim 4, characterized in that: at least one end surface of the nested dielectric resonator block is provided with a film medium. 6. A special-shaped cavity three-mode resonant structure according to claim 1, characterized in that: the concave end surface of the cavity or/and the convex end surface of the dielectric resonator block are provided with thin film dielectrics. 7. A special-shaped cavity three-mode resonant structure according to claim 2, characterized in that: the convex end surface of the cavity or/and the concave end surface of the dielectric resonator block are provided with thin film dielectrics. 8. A special-shaped cavity three-mode resonant structure according to claim 1 or 2, characterized in that: the value of the transition point 1 and the value of the transition point 2 will vary with the dielectric resonator block The resonant frequency of the fundamental mode, the dielectric constant of the dielectric resonator block, and the dielectric constant of the support frame vary. 9. A special-shaped cavity three-mode resonant structure according to claim 1 or 2, characterized in that: when the fundamental mode resonant frequency of the converted dielectric resonator block remains unchanged, the three-mode resonant The Q value of the structure is related to the value of K, the dielectric constant of the dielectric resonant block and the size of the dielectric resonant block. 10. A special-shaped cavity three-mode resonant structure according to claim 1 or 2, characterized in that: when the value of K increases from 1.0 to the maximum, the value of K has three Q within the range of variation Value conversion point, each Q value conversion point makes its fundamental mode Q value and its adjacent high-order mode Q value to the fundamental mode convert; when the fundamental mode Q value is lower than the fundamental mode adjacent to the higher-order mode Q value, the Q value of the higher-order mode adjacent to the fundamental mode is converted into the Q value of the fundamental mode, and the Q value of the fundamental mode is higher than that before conversion; when the Q value of the fundamental mode is higher than the Q value of the higher-order mode adjacent to the fundamental mode , the Q value of the high-order mode adjacent to the fundamental mode is converted into the Q value of the fundamental mode, and the Q value of the fundamental mode is lower than that before the conversion. 11. according to a kind of special-shaped cavity three-mode resonant structure described in claim 10, it is characterized in that: in the 4 regions formed by the initial point, the end point and three Q value conversion points of the value of K, The Q value of the fundamental mode and the Q value of the higher-order mode adjacent to the fundamental mode gradually change with the size of the cavity and the size of the dielectric resonator block. Different regions have different requirements for filters. 12. A special-shaped cavity three-mode resonant structure according to claim 1 or 2, characterized in that: When the dimensions of the cavity and the dielectric resonator block are equal on the X-axis, Y-axis, and Z-axis, a degenerate three-mode is formed, and the degenerate three-mode is coupled with other single cavities to form a passband filter; When the size differences between the cavity and the dielectric resonator block in the three directions of X-axis, Y-axis and Z-axis are slightly unequal, a quasi-orthogonal three-mode resonance is formed. If it can still be coupled into a pass-band filter, the size is acceptable, but if the quasi-orthogonal three-mode and other cavities cannot be coupled into a pass-band filter, the size is not good; When the dimensions of the cavity and the dielectric resonator block are greatly different in the three directions of the X-axis, Y-axis, and Z-axis, they cannot form degenerate three-modes or quasi-orthogonal three-modes, but form three different frequencies. mode, so that it cannot be coupled with other cavities to form a passband filter, the size will not work. 13. A special-shaped cavity three-mode resonant structure according to claim 12, characterized in that: The three-mode resonant structure forms degenerate three-modes in the X-axis, Y-axis, and Z-axis directions, and the resonant frequency of the degenerate three-modes in the X-axis direction passes through the field intensity on one or both sides of the X-axis corresponding to the cavity. Install a tuning screw or a tuning plate in a concentrated place to change the distance or change the capacitance; the resonant frequency in the Y-axis direction is achieved by installing a tuning screw or a tuning plate in the place where the field intensity of the corresponding Y-axis side or both sides of the cavity is concentrated. It can be realized by changing the distance or changing the capacitance; the resonant frequency in the Z-axis direction can be realized by adding a tuning screw or a tuning plate to the place where the field strength is concentrated on one or both sides of the Z-axis corresponding to the cavity to change the distance or change the capacitance. 14. A special-shaped cavity three-mode resonant structure according to claim 11, characterized in that: The three-mode resonant structure forms degenerate three modes in the X-axis, Y-axis and Z-axis directions, and the frequency of the degenerate three modes is adjusted by changing the dielectric constant; the surface of the dielectric resonator block, the cavity The inner wall, the inner wall of the cover plate, or the bottom of the tuning screw are pasted with dielectric constant films of different shapes and thicknesses, and the film materials are ceramic dielectrics and ferroelectric materials; The material of the tuning screw or the tuning disc is metal, or the material of the tuning screw or the tuning disc is metal and the metal surface is electroplated with copper or silver, or the material of the tuning screw or the tuning disc is a medium, or the material of the tuning screw or the tuning disc is It is the medium for surface metallization; The shape of the tuning screw is any one of a metal rod, a dielectric rod, a metal disc, a media disc, a metal rod with a metal disc, a metal rod with a media disc, a media rod with a metal disc, and a media rod with a media disc. 15. A special-shaped cavity three-mode resonant structure according to claim 1 or 2, characterized in that: said three-mode resonant structure is provided with at least two for changing the degenerate three-mode electromagnetic field in the cavity Non-parallel arrangement of coupled structures of orthogonal nature, The coupling structure includes a chamfer/chamfer/groove arranged at the edge of the dielectric resonator block; or include chamfers/chamfers provided at the inner corners of the cavity; Or include chamfering/chamfering/groove next to the edge of the dielectric resonator block and chamfering/chamfering beside the edge of the cavity; Or include tap lines or/sheets arranged on non-parallel planes in the cavity; The shape of the cut corner is triangular prism, cuboid or fan-shaped; after cutting the corner, when the frequency is maintained, the side length of the dielectric resonator block increases, and the Q value decreases slightly; The depth of the chamfer or hole is a through or partial chamfer/partial hole structure according to the size of the required coupling amount; The size of the chamfer/chamfer/hole affects the size of the coupling amount; The coupling structure is arranged with coupling screws in a direction perpendicular to or parallel to the cutting angle, and the material of the coupling screws is metal, or the material of the coupling screws is metal and the metal surface is electroplated with copper or silver, or the material of the coupling screws is a dielectric , or the material of the coupling screw is a surface metallized medium; The shape of the coupling screw is any one of a metal rod, a dielectric rod, a metal disk, a dielectric disk, a metal rod with a metal disk, a metal rod with a dielectric disk, a dielectric rod with a metal disk, or a dielectric rod with a dielectric disk. 16. A special-shaped cavity three-mode resonant structure according to claim 1 or 2, characterized in that: said three-mode resonant structure is provided with at least two for changing the degenerate three-mode electromagnetic field in the cavity Non-parallel arrangement of coupled structures of orthogonal nature, The coupling structure includes a hole/slot arranged on the end face of the dielectric resonator block, the centerline of the hole or the slot is parallel to the edge perpendicular to the end face of the dielectric resonator block where the hole or slot is opened; or include chamfers/chamfers provided at the inner corners of the cavity; Or include chamfering/chamfering beside the hole/groove on the end face of the dielectric resonator block and the edge of the cavity; Or include tap lines or/sheets arranged on non-parallel planes in the cavity; The depth of the hole is a through or partial hole structure according to the size of the required coupling amount; The size of the hole affects the size of the coupling amount; The shape of the hole/slot is circular, rectangular or polygonal. After opening the hole/slot, when the frequency is maintained, the side length of the dielectric resonator increases and the Q value decreases slightly; The coupling structure is arranged with a coupling screw along the direction parallel to the hole, the material of the coupling screw is metal, or the material of the coupling screw is metal and the metal surface is electroplated with copper or silver, or the material of the coupling screw is a medium, or the coupling The material of the screw is the surface metallized medium; The shape of the coupling screw is any one of a metal rod, a dielectric rod, a metal disk, a dielectric disk, a metal rod with a metal disk, a metal rod with a dielectric disk, a dielectric rod with a metal disk, or a dielectric rod with a dielectric disk. 17. A special-shaped cavity three-mode resonant structure according to claim 1 or 2, characterized in that: the shape of the cavity is similar to a cube, in order to realize the coupling between the three modes, without changing the Under the premise of the size of the dielectric resonator block, any two adjacent surfaces of the cavity are processed with cutting edges for realizing the coupling between the three modes, and the size of the cutting edges is related to the required coupling amount; in the three-mode coupling, two The coupling between the molds is realized by cutting the edges of the cavity, and the remaining coupling is realized by cutting the corners of the adjacent two sides of the cavity. It is completely sealed with the cavity; the surface of the cavity is electroplated with copper or silver, and the material of the cavity is metal or non-metal; when the cavity is made of non-metallic material, the inner wall of the cavity must be electroplated with conductive material. 18. A special-shaped cavity three-mode resonant structure according to claim 1 or 2, characterized in that: when the cavity is similar to a cube, the dielectric resonator block and the dielectric support frame are installed on the In any axial direction of the cavity, the center of the dielectric resonator block coincides with or is close to the center of the cavity. 19. A special-shaped cavity three-mode resonance structure according to claim 1 or 2, characterized in that: the dielectric constant of the dielectric support frame is similar to the dielectric constant of air, and the dielectric support frame has a three-mode resonance frequency No effect; the dielectric support frame and the dielectric resonator block are supported on any one side, or on six sides, or on different two, three, four or five sides for different combinations of supports, The medium supporting frame of each surface is a single or multiple medium supporting frames, and one or more supporting frames can be installed on different surfaces as required. 20. A special-shaped cavity three-mode resonant structure according to claim 1 or 2, characterized in that: the dielectric constant of the dielectric support frame is greater than the dielectric constant of air and smaller than the dielectric constant of the dielectric resonator block constant, in order to maintain the original three-mode frequency, the dimension of the dielectric support frame corresponding to the axial direction of the dielectric resonator block is slightly reduced; the dielectric support frame and the dielectric resonator block are supported on any one side, or on six sides Support, or different combinations of two surfaces, three surfaces, four surfaces and five surfaces for different support, the surface without the support frame is air, the air surface and the medium support frame can be combined arbitrarily, the medium of each surface The support frame is a single or multiple dielectric support frames, or a composite dielectric constant support frame composed of multiple layers of dielectric materials with different dielectric constants. The single-layer and multi-layer dielectric material support frames can be combined with similar cube dielectric blocks. One or more support frames can be installed according to the needs. The surface of the support frame is installed. In order to maintain the three-mode frequency and Q value, the dimension of the dielectric support frame corresponding to the axial direction of the dielectric resonator block needs to be slightly reduced. 21. A special-shaped cavity three-mode resonant structure according to claim 20, characterized in that: The single-sided support is combined to support any side of the dielectric resonator block; The support combination of two surfaces includes parallel surfaces, such as top and bottom, front and back, left and right surfaces; it also includes non-parallel surfaces, such as top and front, top and back, top and left, top and right; The support combination of three surfaces includes: three mutually perpendicular surfaces, or two planar surfaces and one non-parallel surface; The support combination of four faces includes: two pairs of parallel faces or a pair of parallel faces and the other two non-parallel faces; The support combination of the five sides includes: any support structure except the front/back/left/right/upper/lower side; The supporting combination of the six sides includes: the supporting structure of all the front/back/left/right/upper/lower sides. 22. A special-shaped cavity three-mode resonant structure according to claim 21, characterized in that the support on one side is combined as a bottom surface or a load-bearing surface in the vertical direction. 23. A special-shaped cavity three-mode resonant structure according to claim 1 or 2, characterized in that: The surface area of the dielectric support frame is less than or equal to the surface area of the dielectric resonator block; the dielectric support frame is a cylinder, a cube or a cuboid; The medium support frame is a solid structure or a hollow structure, and the medium support frame of the hollow structure is single hole or porous, and the shape of the hole is circular, square, polygonal and arc-shaped; The material of the medium support frame includes air, plastic, ceramics, and medium. 24. A special-shaped cavity three-mode resonant structure according to claim 11, characterized in that: the dielectric support frame and the dielectric resonator block are connected by crimping, bonding or burning; The medium supporting frame is connected with the inner wall of the cavity by means of bonding, crimping, welding, burning and screw fixing. 25. A special-shaped cavity three-mode resonant structure according to claim 1 or 2, characterized in that: the radio-frequency path formed by the coupling of radio-frequency signals in the three-mode X, Y and Z-axis directions will cause loss And generate heat, the dielectric resonance block is fully connected with the dielectric support frame and the inner wall of the cavity, so that the heat is introduced into the cavity for heat dissipation. 26. A special-shaped cavity three-mode resonant structure according to claim 1 or 2, characterized in that: the dielectric resonator block controls its frequency temperature coefficient by adjusting the proportion of dielectric materials, according to the filter in The frequency offset change under different temperature conditions is used to compensate. 27. A special-shaped cavity three-mode resonant structure according to claim 25, characterized in that: the dielectric resonator block is a single permittivity or a composite permittivity, and the dielectric resonator block with a composite permittivity consists of Combination of at least two materials with different dielectric constants. Materials with different dielectric constants can be combined up and down, left and right, asymmetrically, and nested; when materials with different dielectric constants are nested in the dielectric resonator block, they can be nested One layer can also be nested with multiple layers, and the dielectric resonator block with composite permittivity needs to comply with the change rule of the aforementioned Q value conversion point; when performing edge-cut coupling between the three modes of the dielectric resonator block, in order to maintain the required frequency , the two adjacent surfaces of the cutting edge need to be adjusted in parallel to the corresponding side length; the dielectric resonator block is made of ceramics or dielectric materials, and dielectric sheets with different thicknesses and different dielectric constants can be added to the surface of the dielectric resonator block. 28. A filter with a special-shaped cavity three-mode resonant structure, including a cavity, a cover plate, and an input and output structure, characterized in that: at least one according to claim 1 or 2 is arranged in the cavity. A special-shaped cavity three-mode resonant structure; The special-shaped cavity three-mode resonant structure is combined with the single-mode resonant structure, the double-mode resonant structure, and the three-mode resonant structure in different forms to form filters of different volumes; The coupling between any two resonant cavities formed by the arrangement and combination of the special-shaped cavity three-mode resonant structure and the single-mode resonant cavity, double-mode resonant cavity, and three-mode resonant cavity must be the resonant rod in the two resonant cavities In the case of parallelism, the coupling can be realized through the size of the window between the two resonators, and the window size is determined according to the size of the coupling amount; The functional characteristics of the filter include band-pass, band-stop, high-pass, low-pass and the duplexer, multiplexer and combiner formed between them.