Dual-mode resonator, dual-mode filter and multiplexer

Abstract

The invention relates to the technical field of filters, in particular to a dual-mode resonator and a dual-mode filter. The dual-mode resonator comprises a metal cavity and a medium resonance body; the number of the metal cavities is two, and the two metal cavities are arranged on the two opposite sides of the medium resonance body respectively. The opening end of the metal cavity faces one end of the dielectric resonator; a conducting ring is arranged between the metal cavity and the dielectric resonant body, and the metal cavity and the conducting ring form 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 conducting rings and the metal cavities are arranged on the two opposite sides of the dielectric resonance body, the conducting rings and the metal cavities form the resonance cavities, and the dual-mode resonance effect is achieved. The overall size is small, the space utilization rate is high, and production is easy.

Description

Technical Field

[0001] The present invention relates to the technical field of filters, and in particular to a dual-mode resonator, a dual-mode filter and a multiplexer. Background Art

[0002] An RF filter is a RF device that filters RF signals. It can filter out interfering signals such as stray harmonics in the RF link, thereby ensuring better transmission of useful signals. It plays a very important role in current wireless communication systems, especially in mobile communication base station equipment.

[0003] There are many ways to implement RF filters, the more common ones include LC filters, coaxial cavity filters, waveguide filters, dielectric filters, and acoustic wave filters.

[0004] Coaxial cavity filters have the characteristics of high power and low loss, and are most widely used in mobile communication base stations.

[0005] The coaxial cavity filter has high power and low loss, but it is relatively large and heavy. In the existing mobile communication base station RF unit, the filter occupies about half of the weight and volume. Therefore, how to reduce the size and weight of the filter while ensuring power and loss has become the main research object of filter design. Summary of the invention

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

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

[0008] It includes a first cavity, a second cavity and a dielectric resonator;

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

[0010] The opening directions of the first cavity and the second cavity are both toward the dielectric resonator;

[0011] Conductive rings are arranged between the dielectric resonator and the first cavity, and between the dielectric resonator and the second cavity;

[0012] The dielectric constant of the first cavity is smaller than the dielectric constant of the dielectric resonator;

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

[0014] In an optional embodiment, at least one inscribed angle is provided inside the conductive ring, and the inscribed angle can change the main resonant frequency and the main mode electric field direction in the resonant cavity;

[0015] The shape of the inscribed angle is one of polygon, fan or arc, or a combination of multiple shapes;

[0016] And / or, the number of the inscribed angles is two, and the two inscribed angles are arranged opposite to each other.

[0017] In an optional implementation, a conductive layer is provided on the outer wall of the dielectric resonator.

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

[0019] And / or, the second cavity is a metal cavity.

[0020] In an optional implementation, the cross-sectional shape of the outer contour of the dielectric resonator is polygonal or circular.

[0021] In an optional implementation, at least one external cut corner is further provided on the conductive ring of the dielectric resonator.

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

[0023] The first resonator is a dual-mode resonator as described in any one of the preceding embodiments;

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

[0025] In an optional embodiment, the second resonator is a coaxial resonator or any of the dual-mode resonators described above.

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

[0027] In a third aspect, the present invention provides a multiplexer comprising the dual-mode filter as described in any one of the above items.

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

[0029] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 A front view of a dual-mode resonator with a square outer profile provided by an embodiment of the present invention;

[0031] Figure 2 for Figure 1 Schematic diagram of the three-dimensional structure;

[0032] Figure 3 A first structural schematic diagram of a conductive ring in a dual-mode resonator is provided for an embodiment of the present invention;

[0033] Figure 4 A second structural schematic diagram of a conductive ring in a dual-mode resonator is provided for an embodiment of the present invention;

[0034] Figure 5 A third structural schematic diagram of a conductive ring in a dual-mode resonator is provided for an embodiment of the present invention;

[0035] Figure 6 A schematic diagram of the three-dimensional structure of a dual-mode filter provided in an embodiment of the present invention;

[0036] Figure 7 for Figure 6 Exploded diagram of

[0037] Figure 8 A schematic diagram of the three-dimensional structure of another dual-mode filter provided by an embodiment of the present invention;

[0038] Fig. 9 for Figure 8 Exploded diagram of

[0039] Fig.10 A schematic diagram of an electric field direction of a dual-mode resonator provided in an embodiment of the present invention;

[0040] Fig.11 A schematic diagram of a first topological structure of a dual-mode filter provided in an embodiment of the present invention;

[0041] Fig.12 for Fig.11 Transmission and reflection curves of

[0042] Fig.13 A schematic diagram of a second topological structure of a dual-mode filter provided in an embodiment of the present invention;

[0043] Fig.14 for Fig.13 Transmission and reflection curves.

[0044] Icons: 1-first cavity; 2-dielectric resonator; 3-conductive ring; 4-second cavity; 5-inner corner; 6-outer corner; 7-input and output ports; 8-coupling window; 9-coupling ring; 10-dual-mode resonator; 11-coaxial filter. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0046] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0048] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, 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 are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0050] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0051] Some embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0052] In a first aspect, the present invention provides a dual-mode resonator, such as Figure 1 and Figure 2 As shown, it includes 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 directions of the first cavity 1 and the second cavity 4 are both toward 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 smaller than the dielectric constant of the dielectric resonator 2; the dielectric constant of the second cavity 4 is smaller 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 the other end open; the dielectric resonator 2 is a dielectric block structure with two end faces being square faces, the four side faces of the dielectric resonator 2 are all provided with conductive layers, and conductive rings 3 are provided on the peripheries of the two square faces of the dielectric body, and the conductive rings 3 are connected to the side conductive layers; the conductive rings 3 are connected to the open ends of the first cavity 1 or the second cavity 4, and resonant cavities are formed at both ends of the dielectric resonator 2.

[0054] In this embodiment, the main resonant modes of the resonant cavity are two orthogonal hybrid merge modes, and their electric field structures are as follows: Fig.10 As shown, the electric field lines of the two modes are distributed along the diagonal lines of the square surface 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 line and are perpendicular to the center of the electric field line. The frequencies of the two main modes can be adjusted by making a cut-off structure on a set of diagonals of the square peripheral conductive ring 3 to form two resonant frequencies F1 and F2 that constitute the filter.

[0055] In this embodiment, the dual-mode resonator adopts a structure with a square end face, which can effectively utilize the space of the filter and further achieve the purpose of reducing weight and volume; and its working mode field distribution is distributed along the diagonal of the square surface, and a tuning rod 6 can be directly added at the diagonal to tune the frequency; in actual use, the conductive layer on the side of the dielectric resonator 2 and the conductive ring 3 use back silver or electroplating technology to attach the metal to the surface of the dielectric resonator 2. And the first cavity 1, the second cavity 4 and the conductive layer of the dielectric resonator 2 are connected, which can be achieved by welding, with a simple production process and high reliability. Usually, the dielectric resonator 2 uses ceramics or other dielectric materials with a dielectric constant of 15 to 85.

[0056] It should be understood that in the present embodiment, the end face of the dual-mode resonator 2 is a square structure, and it may 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, and a dielectric dual-mode resonator can be realized.

[0057] In this embodiment, both the first cavity 1 and the second cavity 4 are 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 constants of the first cavity 1 and the second cavity 4 are 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 resonance frequency and the main mode electric field direction in the resonance cavity.

[0060] Specifically, in this embodiment, the inscribed angle 5 is arranged inside the conductive ring 3, and a plate-like structure is arranged inside the regular part of the 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 resonance frequency is.

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

[0064] In this embodiment, the shape of the inscribed angle 5 can be set to a single polygon, such as a triangle, a rectangle, etc., or it can be set to a single fan-shaped, arc-shaped or other shapes, or it can be set to a combination of multiple polygons, such as a combination of two rectangles (such as Figure 5 As shown in the figure, or a combination of multiple other shapes, or a combination of multiple different shapes, etc. Among them, the same combination of shapes can also have different sizes. In other words, the shape, area and other parameters of the inscribed angle 5 are not unique, as long as they can achieve the adjustment of the main resonant frequency and the main mode electric field direction.

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

[0066] In an optional embodiment, the number of the inscribed corners 5 is two, and the two inscribed corners 5 are arranged opposite to each other.

[0067] In this embodiment, there are two inscribed corners 5 , and the two inscribed corners 5 are arranged opposite to each other inside the conductive ring 3 .

[0068] Specifically, in this embodiment, when the conductive ring 3 is a rectangle or other polygon, the two inscribed corners 5 are respectively arranged at two opposite corners; when the conductive ring 3 is a circle, the two inscribed corners 5 are arranged at two ends of the same diameter.

[0069] Such a setting mode ensures that the adjustment effect of the conductive ring 3 is ensured when it is installed, and at the same time, the requirement for the direction is reduced, thereby reducing the difficulty of installation.

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

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

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

[0073] In this embodiment, the shapes and parameters of the two inscribed corners 5 are exactly the same, which reduces the difficulty of installation. They can also be set to 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 implementation, at least one external corner 6 is provided on the dielectric resonator 2 .

[0075] In this embodiment, the conductive ring 3 is provided with an external cut angle corresponding to the outer contour of the dielectric resonator 2 to achieve structural unity and beautiful appearance.

[0076] In this embodiment, the setting of the external cut corner 6 is equivalent to marking the outer shape of the dielectric resonator 2, so as to facilitate the installation and positioning of the dielectric resonator 2.

[0077] In a second aspect, the present invention provides a dual-mode filter, comprising a first resonator and a second resonator; the first resonator is the dual-mode resonator 10 described in any one of the aforementioned embodiments; the first resonator and the second resonator are connected in series via a coupling structure.

[0078] By adding input and output coupling structures to the two metal cavities of the dual-mode dielectric resonator 2, a dual-mode filter can be directly constructed, such as Figure 6 and Figure 7 As shown, the input and output ports 7 of the filter are arranged on the metal cavity of the dual-mode dielectric resonator 2, and the coupling ring 9 is adopted. The input and output ports 7 are respectively coupled with the two orthogonal modes of the dual-mode dielectric resonator 2 to form a filter with two transmission poles. The topological structure is as follows Fig.11 The transmission and reflection curves are shown in Fig.12 shown.

[0079] In an optional embodiment, the second resonator is a coaxial resonator 11 or any of the dual-mode resonators 10 described above.

[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 this embodiment, two dual-mode resonators 10 are cascaded to realize a filter with four transmission poles. In actual use, the two metal cavities 1 in the middle and the coupling window 8 of the coupling structure form an integrated coupling cavity, and its structure is shown in FIG. Figure 6 and Figure 7 The input and output structure of the filter adopts the structure of a coupling ring 9, and a window is opened in the metal wall connected to the dual-mode resonator 10 for electromagnetic coupling. Its topological structure is as follows Fig.13 The transmission and reflection curves are shown in Fig.14shown.

[0082] It should be noted that, in this embodiment, the second resonator is also a dual-mode resonator 10, but it is not limited to the dual-mode resonator 10, and it can also be cascaded with other forms of resonators to form a mixed mode filter. Figure 8 and Fig. 9 A hybrid coupling filter structure of a dual-mode dielectric resonator 2 and a coaxial resonator 11 is given, wherein the input port and the output port 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 is shown in FIG. Fig.13 As shown, the filter transmission and reflection curves are as follows Fig.14 shown.

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

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

[0085] The combined circuit of two filters working in different frequency bands can be used as a frequency division duplexer. Therefore, the dielectric multimode resonator obtained by the deformed structure in this embodiment can also be used in duplexer and multiplexer products.

[0086] In a third aspect, the present invention further provides a multiplexer, which includes the dual-mode filter described in any one of the above embodiments.

[0087] The dual-mode resonator 10 and dual-mode filter provided by the present invention achieve the effect of dual-mode resonance by arranging a conductive ring 3 and a metal cavity 1 on opposite sides of a dielectric resonator 2, and the conductive ring 3 and the metal cavity 1 constitute a resonant cavity. The overall volume is small, the space utilization rate is high, and it 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 invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A dual-mode resonator, characterized in that: It includes a first cavity, a second cavity and a dielectric resonator; The first cavity and the second cavity are respectively arranged on two opposite sides of the dielectric resonator; The opening directions of the first cavity and the second cavity are both toward the dielectric resonator; Conductive rings are arranged between the dielectric resonator and the first cavity, and between the dielectric resonator and the second cavity; The dielectric constant of the first cavity is smaller than the dielectric constant of the dielectric resonator; The dielectric constant of the second cavity is smaller than the dielectric constant of the dielectric resonator.

2. The dual-mode resonator according to claim 1, characterized in that: At least one inscribed angle is provided inside the conductive ring, and the inscribed angle can change the main resonant frequency and the main mode electric field direction in the resonant cavity; The shape of the inscribed angle is one of polygon, fan or arc, or a combination of multiple shapes; And / or, the number of the inscribed angles is two, and the two inscribed angles are arranged opposite to each other.

3. The dual-mode resonator according to claim 1, characterized in that: A conductive layer is arranged on the outer wall of the dielectric resonator.

4. The dual-mode resonator according to claim 1, characterized in that: The first cavity is a metal cavity; And / or, the second cavity is a metal cavity.

5. The dual-mode resonator according to claim 1, characterized in that: The cross-sectional shape of the outer contour of the dielectric resonator is polygonal or circular.

6. The dual-mode resonator according to claim 2, characterized in that: The dielectric resonator is provided with at least one external cut corner.

7. A dual-mode filter, characterized in that: including a first resonator and a second resonator; The first resonator is a dual-mode resonator according to any one of claims 1 to 6; The first resonator and the second resonator are connected in series via a coupling structure.

8. The dual-mode filter according to claim 7, characterized in that: The second resonator is a coaxial resonator or a dual-mode resonator as described in any one of claims 1 to 6.

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

10. A multiplexer, characterized in that: A dual-mode filter comprising the method described in any one of claims 7 to 9.

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