A dual-mode resonator, dual-mode filter and multiplexer

Abstract

The present application relates to the technical field of filter, especially to a dual-mode resonator and a dual-mode filter. The dual-mode resonator comprises a metal cavity and a dielectric resonator body; the number of the metal cavities is two, and the two metal cavities are arranged on opposite sides of the dielectric resonator body respectively; the open end of the metal cavity faces one end of the dielectric resonator body; a conductive ring is arranged between the metal cavity and the dielectric resonator body, and the metal cavity and the conductive ring constitute a resonant cavity. The dual-mode filter comprises a first resonator and a second resonator; the first resonator is a dual-mode resonator; the first resonator and the second resonator are connected in series through a coupling structure. The present application sets the conductive ring and the metal cavity on opposite sides of the dielectric resonator body, and the conductive ring and the metal cavity constitute a resonant cavity, so as to achieve the effect of dual-mode resonance. The overall volume is small, the space utilization rate is high, and the production is easy.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of filter, in particular to a dual-mode resonator, dual-mode filter and multiplexer. BACKGROUND

[0002] The radio frequency filter is a kind of radio frequency device for filtering radio frequency signals, which can filter out interference signals such as spurious harmonics in radio frequency link, so as to ensure better transmission of useful signals, and plays a very important role in the current wireless communication system, especially in mobile communication base station equipment.

[0003] There are many implementation methods of radio frequency filter, and the more common ones include LC filter, coaxial cavity filter, waveguide filter, dielectric filter and acoustic wave filter, etc.

[0004] The coaxial cavity filter has the characteristics of high power and low loss, and is most widely used in mobile communication base station.

[0005] The coaxial cavity filter has high power and low loss, but its volume is relatively large and its weight is relatively heavy. In the existing mobile communication base station radio frequency unit, the filter occupies about one half of the weight and volume. Therefore, how to reduce the volume and weight of the filter under the conditions of power and loss has become the main research object of the current filter design. SUMMARY

[0006] The purpose of the present application is to provide a dual-mode resonator, dual-mode filter and multiplexer, which solves the technical problems existing in the prior art.

[0007] In a first aspect, the present application provides a dual-mode resonator,

[0008] comprising a first cavity, a second cavity and a dielectric resonator body;

[0009] The first cavity and the second cavity are respectively arranged on opposite sides of the dielectric resonator body;

[0010] The opening direction of the first cavity and the second cavity is towards the dielectric resonator body;

[0011] The dielectric constant of the first cavity is smaller than that of the dielectric resonator body;

[0012] The dielectric constant of the second cavity is smaller than that of the dielectric resonator body.

[0013] The dielectric constant of the second cavity is smaller than that of the dielectric resonator body.

[0014] In an optional embodiment, the inner side of the conductive ring is provided with at least one inscribed angle, which can change the main resonant frequency and the main mode electric field direction in the resonant cavity.

[0015] The inscribed angle is in the shape of one of a polygon, a sector or an arc, or a combination of multiple shapes.

[0016] The number of the inscribed angles is two, and the two inscribed angles are oppositely arranged.

[0017] In an optional embodiment, the outer wall of the dielectric resonant body is provided with a conductive layer.

[0018] In an optional embodiment, the first cavity is a metal cavity.

[0019] The second cavity is a metal cavity.

[0020] In an optional embodiment, the cross-sectional shape of the outer contour of the dielectric resonant body is a polygon or a circle.

[0021] In an optional embodiment, the conductive ring of the dielectric resonant body is further provided with at least one circumscribed angle.

[0022] In a second aspect, the present application provides a dual-mode filter, comprising a first resonator and a second resonator.

[0023] The first resonator is the dual-mode resonator according to any one of the preceding embodiments.

[0024] The first resonator and the second resonator are connected in series through a coupling structure.

[0025] In an optional embodiment, the second resonator is a coaxial resonator or the dual-mode resonator according to any one of the preceding embodiments.

[0026] In an optional embodiment, the number of the first resonators is multiple, and the number of the second resonators is multiple.

[0027] In a third aspect, the present application provides a multiplexer, comprising the dual-mode filter according to any one of the preceding embodiments.

[0028] The dual-mode resonator, the dual-mode filter and the multiplexer provided by the present application achieve the effect of dual-mode resonance by arranging conductive rings and metal cavities on opposite sides of a dielectric resonant body, which form a resonant cavity. The overall volume is small, the space utilization is high, and the production is easy. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the specific embodiments of the present application or the prior art, the accompanying drawings needed to be used in the description of the specific embodiments or the prior art will be briefly introduced. Obviously, the accompanying drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort based on these drawings.

[0030] Figure 1 The front view of the square outer contour dual-mode resonator provided by the embodiment of the present application;

[0031] Figure 2 The perspective structural schematic diagram of Figure 1 ;

[0032] Figure 3 The first structural schematic diagram of the conductive ring in the dual-mode resonator provided by the embodiment of the present application;

[0033] Figure 4 The second structural schematic diagram of the conductive ring in the dual-mode resonator provided by the embodiment of the present application;

[0034] Figure 5 The third structural schematic diagram of the conductive ring in the dual-mode resonator provided by the embodiment of the present application;

[0035] Figure 6 The perspective structural schematic diagram of the dual-mode filter provided by the embodiment of the present application;

[0036] Figure 7 The exploded view of Figure 6 ;

[0037] Figure 8 The perspective structural schematic diagram of another dual-mode filter provided by the embodiment of the present application;

[0038] Figure 9 The exploded view of Figure 8 ;

[0039] Figure 10 The electric field direction schematic diagram of the dual-mode resonator provided by the embodiment of the present application;

[0040] Figure 11 The first topological structural schematic diagram of the dual-mode filter provided by the embodiment of the present application;

[0041] Figure 12 The transmission and reflection curve diagram of Figure 11 ;

[0042] Figure 13 The second topological structural schematic diagram of the dual-mode filter provided by the embodiment of the present application;

[0043] Figure 14 For Figure 13 transmission and reflection curves.

[0044] Legend: 1 - first cavity; 2 - dielectric resonator; 3 - conducting loop; 4 - second cavity; 5 - inscribed angle; 6 - circumscribed angle; 7 - input / output port; 8 - coupling window; 9 - coupling loop; 10 - dual-mode resonator; 11 - coaxial filter. DETAILED DESCRIPTION

[0045] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application but not all the embodiments. The components of the embodiments of the present application described and shown in the drawings can be arranged and designed in various different configurations.

[0046] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed application, but only represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative work fall within the scope of protection of the present application.

[0047] It should be noted that: similar reference numerals and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0048] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship when the product of the present application is usually placed, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third" and the like are only used for differentiation and cannot be understood as indicating or implying relative importance.

[0049] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components must be absolutely horizontal or overhanging, but can be slightly inclined. For example, "horizontal" only means that its direction is relatively more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0050] In the description of the present application, it is also necessary to point out that, unless otherwise explicitly specified and limited, the terms "arrange", "mount", "connect", "connect" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be connected inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0051] Some embodiments of the present application will be described in detail below with reference to the accompanying drawings. The following examples and features in the examples can be combined with each other without conflict.

[0052] In a first aspect, the present application provides a dual-mode resonator, as shown in Figure 1 and Figure 2 It comprises a first cavity 1, a second cavity 4 and a dielectric resonator 2; the first cavity 1 and the second cavity 4 are respectively arranged on opposite sides of the dielectric resonator 2; the opening direction of the first cavity 1 and the second cavity 4 is towards the dielectric resonator 2; a conductive ring 3 is arranged between the dielectric resonator 2 and the first cavity 1, and between the dielectric resonator 2 and the second cavity 4; the dielectric constant of the first cavity 1 is less than the dielectric constant of the dielectric resonator 2; the dielectric constant of the second cavity 4 is less than the dielectric constant of the dielectric resonator 2.

[0053] In this embodiment, the dual-mode resonator is composed of two cavities and a dielectric resonator 2, both of which are conductive cavity structures with one end closed and one end open; the dielectric resonator 2 is a dielectric block structure with two square faces on the ends, and a conductive layer is arranged on each of the four sides of the dielectric resonator 2, and a conductive ring 3 is arranged on the periphery of the two square faces of the dielectric body, and the conductive ring 3 is connected with the side conductive layer; the conductive ring 3 is connected with the open end of the first cavity 1 or the second cavity 4, forming a resonant cavity at both ends of the dielectric resonator 2.

[0054] In this embodiment, the main resonant mode of the resonant cavity is two orthogonal mixed and merged modes, and the electric field structure is as shown in Figure 10 The electric field lines of the two modes are respectively distributed along the diagonal lines of the square faces of the dielectric resonator 2, and are perpendicular to each other; the magnetic field lines of each resonant mode are distributed around the center of the electric field lines, and are perpendicular to the center of the electric field lines. The frequencies of the two main modes can be adjusted by making a cut angle structure on a group of diagonals of the peripheral conductive ring 3 of the square, so as to form two resonant frequencies F1 and F2 which constitute the filter.

[0055] In this embodiment, the dual-mode resonator adopts a structure with square end faces, which can effectively utilize the space of the filter and further achieve the purpose of reducing weight and volume. In addition, its operating mode field distribution is distributed along the diagonals of the square faces, and tuning rods can be directly added at the diagonals for frequency tuning. In actual use, the conductive layer on the side of the dielectric resonator 2 and the conductive ring 3 are attached to the surface of the dielectric resonator 2 using a back-silver or electroplating process. The first cavity 1, the second cavity 4, and the conductive layer of the dielectric resonator 2 are connected by welding, which is simple to produce and highly reliable. The dielectric resonator 2 is typically made of ceramic or other dielectric materials with a dielectric constant of 15 to 85.

[0056] It should be understood that in this embodiment, the end face of the dual-mode resonator 2 is a square structure, and it can also adopt other shapes, such as a circular structure, a hexagonal structure, an octagonal structure, etc. As long as a conductive ring 3 is made on the periphery of the two end faces of the dielectric resonator 2 and a conductive layer is made on the side wall, the conductive ring 3 connected to the open end faces of the first cavity 1 and the second cavity 4 with the same end face shape as the dielectric resonator 2 is connected to form a closed cavity structure, a dielectric dual-mode resonator can be realized.

[0057] In this embodiment, the first cavity 1 and the second cavity 4 are both metal cavities. The metal cavity is provided mainly to utilize its conductive property to achieve a filtering function.

[0058] It is understandable that the first cavity 1 and the second cavity 4 can both be metal cavities, or any one of them can be a metal cavity, as long as the dielectric constant of the first cavity 1 and the second cavity 4 is lower than the dielectric constant of the dielectric resonator.

[0059] In an optional embodiment, at least one inscribed angle 5 is provided inside the conductive ring 3 , and the inscribed angle 5 can change the main resonant frequency and the main mode electric field direction in the resonant cavity.

[0060] Specifically, in this embodiment, the inscribed angle 5 is set inside the conductive ring 3, and a plate-shaped structure is set inside the regular conductive ring 3 to change its corresponding regular shape, thereby achieving the purpose of changing the main resonant frequency and the main mode electric field direction.

[0061] More specifically, in this embodiment, the number of the inscribed angles 5 can be one or more, such as two, three, four, etc., as long as the main resonant frequency and the main mode electric field direction are changed by setting the inscribed angles 5.

[0062] In this embodiment, the larger the area of ​​the inscribed angle 5 of the conductive ring 3 is, the higher the resonant frequency is.

[0063] In an optional embodiment, if Figure 3-Figure 5As shown, the shape of the inscribed angle 5 is one of a polygon, a sector, or an arc, or a combination of multiple shapes.

[0064] In this embodiment, the shape of the inscribed angle 5 can be set as a single polygon, such as a triangle, a rectangle, etc., or a single sector, an arc, or other shapes, or a combination of multiple polygons, such as two rectangles combined (e.g. Figure 5 As shown), or a combination of multiple other shapes, or a combination of multiple different shapes, etc. Among them, the same shape can be combined in different sizes.

[0065] In this embodiment, when adjusting the main resonant frequency and the main mode electric field direction, different conductive rings 3 with different inscribed angles 5 can be replaced according to different requirements.

[0066] In an optional embodiment, the number of the inscribed angles 5 is two, and the two inscribed angles 5 are oppositely arranged.

[0067] In this embodiment, the number of the inscribed angles 5 is two, and the two inscribed angles 5 are oppositely arranged inside the conductive ring 3.

[0068] Specifically, in this embodiment, when the conductive ring 3 is rectangular or other polygonal, the two inscribed angles 5 are arranged at the opposite two corners, and when the conductive ring 3 is circular, the two inscribed angles 5 are arranged at the two ends of the same diameter.

[0069] Such arrangement reduces the requirement for direction when the conductive ring 3 is installed, thereby reducing the installation difficulty.

[0070] In this embodiment, the inscribed angle 5 is added to the conductive ring 3 to adjust the resonant frequency and the electric field line direction of the two main modes, and the size of the two focusing inscribed angles can be adjusted according to the required frequency, and the shape can be designed as a square, a T-shaped structure, etc. The diagonal structure can be symmetrical or asymmetric. By arranging different structures on the diagonals of the conductive ring 3 to change the frequency and electric field line direction of the two orthogonal modes of the double-mode dielectric resonator 2, which is one of the main features of the present application.

[0071] It can be understood that the number of the inscribed angle 5 can be two, but it is not limited to two, and it can also be one, three, four, etc. As long as different inscribed angles 5 positions and the number of inscribed angles 5 can adjust different main resonant frequencies and main mode electric field directions.

[0072] In an optional embodiment, the shapes of the two inscribed angles 5 are the same or different.

[0073] In the embodiment, the shapes and parameters of the two inscribed angles 5 are completely identical, which reduces the installation difficulty, and the inscribed angles can also be different, as long as they are set according to the requirements of the main resonant frequency and the main mode electric field direction.

[0074] In an optional embodiment, at least one circumscribed angle 6 is arranged on the dielectric resonant body 2.

[0075] In the embodiment, the conductive ring 3 is provided with a circumscribed angle corresponding to the outer contour of the dielectric resonant body 2, so as to realize the unity of the structure and the beauty of the appearance.

[0076] In the embodiment, the setting of the circumscribed angle 6 is equivalent to marking the shape of the dielectric resonant body 2, thereby facilitating the positioning of the installation of the dielectric resonant body 2.

[0077] In a second aspect, the application provides a dual-mode filter, which comprises a first resonator and a second resonator; the first resonator is the dual-mode resonator 10 of any one of the preceding embodiments; and the first resonator and the second resonator are connected in series through a coupling structure.

[0078] The input and output coupling structures are added to the two metal cavities of the dual-mode dielectric resonant body 2, so as to directly form a dual-mode filter, as shown in Figure 6 and Figure 7 The input and output ports 7 of the filter are arranged on the metal cavities of the dual-mode dielectric resonant body 2 in the form of a coupling ring 9, and the input and output ports 7 are respectively coupled with the two orthogonal modes of the dual-mode dielectric resonant body 2, so as to form a filter with two transmission poles, and the topological structure is as shown in Figure 11 , and the transmission and reflection curves are as shown in Figure 12 .

[0079] In an optional embodiment, the second resonator is a coaxial resonator 11 or the dual-mode resonator 10 of any one of the preceding embodiments.

[0080] Based on the above filter case, two dual-mode resonators 10 are used to cooperate with each other to obtain a dual-mode filter.

[0081] Specifically, in the embodiment, the two dual-mode resonators 10 are connected in series, so as to realize a filter with four transmission poles. In actual use, the two metal cavities 1 at the middle position and the coupling windows 8 of the coupling structure constitute an integral coupling cavity, and the structural diagram is as shown in Figure 6 and Figure 7 The input and output structure of the filter adopts the structure form of the coupling ring 9, and the metal walls of the dual-mode resonators 10 are windowed to be electromagnetically coupled, and the topological structure is as shown in Figure 13 , and the transmission and reflection curves are as shown in Figure 14as shown.

[0082] It should be noted that in the present embodiment, the second resonator is also a dual-mode resonator 10, but it is not limited to a dual-mode resonator 10, and it can also be cascaded with other forms of resonators to form a hybrid mode filter, Figure 8 and Figure 9 A hybrid coupling filter structure of a dual-mode dielectric resonator 2 and a coaxial resonator 11 is given, the input port and the output port of which are directly connected to the coaxial resonator 11, and the coaxial resonator 11 is electromagnetically coupled to the dielectric dual-mode resonator 10 through a coupling window 8 structure, the topological structure of which is shown in Figure 13 , and the filter transmission and reflection curves are shown in Figure 14 .

[0083] In an optional embodiment, the number of the first resonators is multiple, and the number of the second resonators is multiple.

[0084] The input and output structure of the hybrid coupling filter is flexible, which brings great advantages to the design and production of the dual-mode filter, and through cascading more dual-mode dielectric resonators 2 or other types of resonators, a filter with more transmission zeros can be realized, and higher suppression and transmission characteristics can be realized.

[0085] The combination of the two filters working at different frequency bands can be used as a frequency division duplex filter, and therefore, the dielectric multi-mode resonator obtained through the deformation structure in the present embodiment can also be applied in duplexers and multiplexers.

[0086] In a third aspect, the present application also provides a multiplexer comprising the dual-mode filter of any one of the above embodiments.

[0087] The dual-mode resonator 10 and the dual-mode filter provided by the present application achieve the effect of dual-mode resonance by arranging the conductive ring 3 and the metal cavity 1 on the opposite sides of the dielectric resonator 2, and the conductive ring 3 and the metal cavity 1 constitute a resonant cavity, which has a small overall volume, high space utilization, and is easy to produce.

[0088] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the above embodiments, or make equivalent replacement to part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A dual-mode resonator, characterized by, The dual-mode resonator comprises a first cavity, a second cavity and a dielectric resonant body. The first cavity and the second cavity are respectively arranged on opposite sides of the dielectric resonant body. The opening direction of the first cavity and the second cavity is towards the dielectric resonant body. A conductive ring is arranged between the dielectric resonant body and the first cavity and between the dielectric resonant body and the second cavity. The conductive ring and the first cavity connected thereto and the conductive ring and the second cavity connected thereto form a resonant cavity. The dielectric constant of the first cavity is less than the dielectric constant of the dielectric resonant body. The dielectric constant of the second cavity is less than the dielectric constant of the dielectric resonant body. The conductive ring is internally provided with at least one inscribed angle, which can change the main resonant frequency and the main mode electric field direction in the resonant cavity. When adjusting the main resonant frequency and the main mode electric field direction, the conductive ring with different inscribed angles can be replaced according to different requirements. A tuning rod is arranged at the diagonal of the resonant cavity for frequency tuning. The dielectric resonant body is provided with at least one circumscribed angle.

2. The dual-mode resonator of claim 1, wherein The shape of the inscribed angle is one of a polygon, a sector or an arc, or a combination of multiple shapes. And / or, the number of inscribed angles is two, and the two inscribed angles are oppositely arranged.

3. The dual-mode resonator of claim 1, wherein The dielectric resonant body is provided with a conductive layer on the outer wall.

4. The dual-mode resonator of claim 1, wherein, The first cavity is a metal cavity. And / or, the second cavity is a metal cavity.

5. The dual-mode resonator of claim 1, wherein, The cross-sectional shape of the outer contour of the dielectric resonant body is a polygon or a circle.

6. A dual-mode filter, characterized by The dual-mode filter comprises a first resonator and a second resonator. The first resonator is the dual-mode resonator of any one of claims 1-5. The first resonator and the second resonator are connected in series through a coupling structure.

7. The dual-mode filter of claim 6, wherein, The second resonator is a coaxial resonator or the dual-mode resonator of any one of claims 1-5.

8. The dual-mode filter according to claim 6 or 7, characterized in that The number of the first resonators is multiple, and the number of the second resonators is multiple.

9. A multiplexer, characterized by The dual-mode filter comprises the dual-mode resonator of any one of claims 6-8.

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