Dual-mode resonator, dual-mode filter and multiplexer
By setting conductive rings and metal cavities on both sides of the dielectric resonator, the problem of large size and heavy weight of coaxial cavity filters is solved, realizing miniaturized and lightweight filter design with high power and low loss performance.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- RSINNC TECHNOLOGIES LTD
- Filing Date
- 2025-03-26
- Publication Date
- 2026-05-15
AI Technical Summary
Existing coaxial cavity filters are large and heavy in mobile communication base stations, making it difficult to reduce their size and weight while ensuring power and loss.
The dual-mode resonator design utilizes conductive rings and metal cavities on opposite sides of the dielectric resonator to form a resonant cavity. By taking advantage of the difference in dielectric constants between the conductive rings and the metal cavity, the dual-mode resonance effect is achieved, reducing the overall volume and improving space utilization.
This achieves a reduction in filter size and weight while maintaining high power and low loss performance, and is easy to manufacture and install.
Smart Images
Figure CN2025084909_15052026_PF_FP_ABST
Abstract
Description
A dual-mode resonator, a dual-mode filter, and a multiplexer
[0001] Cross-reference to related applications
[0002] This application claims priority to Chinese Patent Application No. 2024116000772, filed on November 11, 2024, entitled "A Dual-Mode Resonator, Dual-Mode Filter and Multiplexer", the entire contents of which are incorporated herein by reference. Technical Field
[0003] This disclosure relates to the field of filter technology, and in particular to a dual-mode resonator, a dual-mode filter, and a multiplexer. Background Technology
[0004] Radio frequency (RF) filters are RF devices that filter RF signals, removing spurious harmonics and other interference signals from the RF link to ensure better transmission of useful signals. They play a crucial role in modern wireless communication systems, especially in mobile communication base station equipment. There are many ways to implement RF filters, the most common including LC filters, coaxial cavity filters, waveguide filters, dielectric filters, and acoustic filters. Coaxial cavity filters, with their high power and low loss characteristics, are the most widely used in mobile communication base stations.
[0005] Coaxial cavity filters have high power and low loss, but they are relatively large and heavy. In existing mobile communication base station radio frequency units, filters account for about half of the weight and volume. Therefore, how to reduce the size and weight of filters while ensuring power and loss has become the main research object of filter design. Summary of the Invention
[0006] The purpose of this disclosure is to provide a dual-mode resonator, a dual-mode filter, and a multiplexer that solves the technical problems of large size and heavy weight in the prior art.
[0007] In a first aspect, embodiments of this disclosure provide a dual-mode resonator, including a first cavity, a second cavity, and a dielectric resonator;
[0008] The first cavity and the second cavity are respectively disposed on opposite sides of the dielectric resonator;
[0009] The openings of both the first cavity and the second cavity are oriented towards the dielectric resonator;
[0010] A conductive ring is provided between the dielectric resonator and the first cavity, and between the dielectric resonator and the second cavity;
[0011] The dielectric constant of the first cavity is less than the dielectric constant of the dielectric resonator;
[0012] The dielectric constant of the second cavity is less than the dielectric constant of the dielectric resonator.
[0013] In an optional embodiment, the conductive ring has at least one incised angle inside, which can change the main resonant frequency and the direction of the main mode electric field inside the resonant cavity;
[0014] The shape of the inscribed angle is one of a polygon, a sector, or an arc, or a combination of several shapes;
[0015] And / or, the number of the inscribed angles is two, and the two inscribed angles are set opposite to each other.
[0016] In an optional embodiment, a conductive layer is provided on the outer wall of the dielectric resonator.
[0017] In an optional embodiment, the first cavity is a metal cavity;
[0018] And / or, the second cavity is a metal cavity.
[0019] In an optional embodiment, the cross-sectional shape of the outer contour of the dielectric resonator is polygonal or circular.
[0020] In an optional embodiment, the dielectric resonator conductive ring is further provided with at least one external tangent.
[0021] Secondly, embodiments of this disclosure provide a dual-mode filter, including a first resonator and a second resonator;
[0022] The first resonator is a dual-mode resonator as described in any of the foregoing embodiments;
[0023] The first resonator and the second resonator are connected in series through a coupling structure.
[0024] In an optional embodiment, the second resonator is a coaxial resonator or a dual-mode resonator as described in any of the preceding embodiments.
[0025] In an optional implementation, the number of the first resonators is multiple, and the number of the second resonators is multiple.
[0026] Thirdly, embodiments of this disclosure provide a multiplexer including the dual-mode filter described in any of the preceding claims.
[0027] The embodiments of this disclosure provide a dual-mode resonator, a dual-mode filter, and a multiplexer. The dual-mode resonator includes a first cavity, a second cavity, and a dielectric resonator. The first cavity and the second cavity are respectively disposed on opposite sides of the dielectric resonator. The openings of both the first cavity and the second cavity face the dielectric resonator. Conductive rings are disposed 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 less than that of the dielectric resonator; the dielectric constant of the second cavity is less than that of the dielectric resonator. By disposing conductive rings and metal cavities on opposite sides of the dielectric resonator, the conductive rings and metal cavities constitute a resonant cavity, achieving the effect of dual-mode resonance. The overall size is small, space utilization is high, and it is easy to manufacture. Attached Figure Description
[0028] To more clearly illustrate the technical solutions in the specific embodiments of this disclosure or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0029] Figure 1 is a front view of a dual-mode resonator with a square outer contour provided in an embodiment of this disclosure;
[0030] Figure 2 is a schematic diagram of the three-dimensional structure of Figure 1;
[0031] Figure 3 is a schematic diagram of the conductive ring in a dual-mode resonator provided in an embodiment of this disclosure;
[0032] Figure 4 is a schematic diagram of the conductive ring in a dual-mode resonator provided in an embodiment of this disclosure;
[0033] Figure 5 is a schematic diagram of the conductive ring in a dual-mode resonator provided in an embodiment of this disclosure;
[0034] Figure 6 is a three-dimensional structural diagram of the dual-mode filter provided in the embodiment of this disclosure;
[0035] Figure 7 is an exploded view of Figure 6;
[0036] Figure 8 is a three-dimensional structural diagram of the dual-mode filter provided in the embodiment of this disclosure;
[0037] Figure 9 is an exploded view of Figure 8;
[0038] Figure 10 is a schematic diagram of the electric field direction of the dual-mode resonator provided in the embodiment of this disclosure;
[0039] Figure 11 is a schematic diagram of the topology of the dual-mode filter provided in the embodiment of this disclosure;
[0040] Figure 12 shows the transmission and reflection curves of Figure 11;
[0041] Figure 13 is a schematic diagram of the topology of the dual-mode filter provided in the embodiment of this disclosure;
[0042] Figure 14 shows the transmission and reflection curves of Figure 13.
[0043] Icons: 1-First cavity; 2-Dielectric resonator; 3-Conducting ring; 4-Second cavity; 5-Inner tangent; 6-Outer tangent; 7-Input / output port; 8-Coupled window; 9-Coupled ring; 10-Dual-mode resonator; 11-Coaxial filter. Detailed Implementation
[0044] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. The components of the embodiments of this disclosure described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0045] Therefore, the following detailed description of the embodiments of this disclosure provided in the accompanying drawings is not intended to limit the scope of the claimed disclosure, but merely to illustrate selected embodiments of the disclosure. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without inventive effort are within the scope of protection of this disclosure.
[0046] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0047] In the description of this disclosure, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use. They are used only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this disclosure. In addition, the terms "first," "second," and "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0048] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.
[0049] In the description of this disclosure, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure based on the specific circumstances.
[0050] The following detailed description of some embodiments of this disclosure is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.
[0051] The embodiments of this disclosure provide a dual-mode resonator, as shown in Figures 1 and 2, including a first cavity 1, a second cavity 4, and a dielectric resonator 2; the first cavity 1 and the second cavity 4 are respectively disposed on opposite sides of the dielectric resonator 2; the opening directions of the first cavity 1 and the second cavity 4 are both facing the dielectric resonator 2; a conductive ring 3 is disposed between the dielectric resonator 2 and the first cavity 1 or 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.
[0052] In this embodiment, the dual-mode resonator consists of two cavities and a dielectric resonator 2. Both cavities are conductive cavity structures that are closed at one end and open at the other. The dielectric resonator 2 is a dielectric block structure with two square end faces. Conductive layers are provided on all four sides of the dielectric resonator 2, and conductive rings 3 are provided around the two square faces of the dielectric body. 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, forming resonant cavities at both ends of the dielectric resonator 2.
[0053] In this embodiment, the main resonant modes of the resonant cavity are two orthogonal hybrid modes, and their electric field structures are shown in Figure 10. The electric field lines of the two modes are distributed along the diagonals of the square face 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 chamfered structures on a set of diagonals of the conductive ring 3 on the outer perimeter of the square to form the two resonant frequencies F1 and F2 that make up the filter.
[0054] In this embodiment, the dual-mode resonator adopts a square end face structure, which can effectively utilize the filter space and further reduce weight and volume. Furthermore, its operating mode field distribution follows the diagonal of the square face, allowing for direct frequency tuning by adding tuning rods 6 at the diagonal. In practical use, the conductive layer and conductive ring 3 on the side of the dielectric resonator 2 are attached to the surface of the dielectric resonator 2 using a back-silvering or electroplating process. The first cavity 1 and the second cavity 4 are connected to the conductive layer of the dielectric resonator 2, which can be achieved through welding, resulting in a simple manufacturing process and high reliability. Typically, the dielectric resonator 2 uses ceramic or other dielectric materials with a dielectric constant of 15–85.
[0055] It should be understood that in this embodiment, the end face of the dual-mode resonator 2 is a square structure, but it can also adopt other shapes, such as a circular structure, a hexagonal structure, or an octagonal structure, etc. As long as conductive rings 3 are made on the outer periphery of the two end faces of the dielectric resonator 2 and conductive layers are made on the side walls, and the conductive rings 3 connected to the open end faces of the first cavity 1 and the second cavity 4 with the same shape as the end face of the dielectric resonator 2 are connected to form a closed cavity structure, a dielectric dual-mode resonator can be realized.
[0056] In this embodiment, both the first cavity 1 and the second cavity 4 are metal cavities. The metal cavities are mainly used to achieve the filtering function by utilizing their conductivity. It can be understood that both the first cavity 1 and the second cavity 4 can be metal cavities, or either 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.
[0057] In an optional embodiment, the conductive ring 3 has at least one incised angle 5 inside, which can change the main resonant frequency and the direction of the main mode electric field within the resonant cavity. Specifically, in this embodiment, the incised angle 5 is located inside the conductive ring 3, and a plate-like structure is provided inside the regular shape of the conductive ring 3 to change its corresponding regular shape, thereby achieving the purpose of changing the main resonant frequency and the direction of the main mode electric field. More specifically, in this embodiment, the number of incised angles 5 can be one or more, such as two, three, or four, as long as the main resonant frequency and the direction of the main mode electric field are changed by setting the incised angle 5.
[0058] In this embodiment, the larger the area of the inner incised angle 5 of the conductive ring 3, the higher the resonant frequency. In optional embodiments, as shown in Figures 3-5, the shape of the inner incised angle 5 can be one or a combination of polygons, sectors, or arcs. In this embodiment, the shape of the inner incised angle 5 can be a single polygon, such as a triangle or rectangle, or a single sector or arc, or a combination of multiple polygons, such as two rectangles (as shown in Figure 5), or a combination of multiple other shapes, or a combination of multiple different shapes. Even combinations of the same shape can have different sizes. In other words, the shape, area, and other parameters of the inner incised angle 5 are not unique; they only need to be able to adjust the main resonant frequency and the direction of the main mode electric field.
[0059] In this embodiment, when adjusting the main resonant frequency and the direction of the main mode electric field, the conductive ring 3 with different inner tangent angles 5 can be replaced according to different requirements. In an optional embodiment, the number of inner tangent angles 5 is two, and the two inner tangent angles 5 are arranged opposite to each other. In this embodiment, the number of inner tangent angles 5 is two, and the two inner tangent angles 5 are arranged opposite to each other inside the conductive ring 3.
[0060] Specifically, in this embodiment, when the conductive ring 3 is rectangular or other polygonal, the two inscribed angles 5 are respectively set at two opposite corners; when the conductive ring 3 is circular, the two inscribed angles 5 are set at both ends of the same diameter. This arrangement ensures the adjustment effect while reducing the directional requirements during installation, thus reducing the installation difficulty.
[0061] In this embodiment, an inner tangent angle 5 is added to the conductive ring 3 to adjust the resonant frequency and electric field line direction of the two main modes. The size of the two focusing tangent angles can be adjusted according to the required frequency, and their shape can also be designed as a square or T-shaped structure. The diagonal structure can be symmetrical or asymmetrical. Changing the frequency and electric field line direction of the two orthogonal modes of the dual-mode dielectric resonator 2 by setting different structures on the diagonals of the conductive ring 3 is one of the main features of this disclosure.
[0062] It is understandable that the number of 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 positions and numbers of inscribed angles 5 can be used to adjust different main resonant frequencies and main mode electric field directions.
[0063] In optional embodiments, the two inner corners 5 may have the same or different shapes. In this embodiment, the two inner corners 5 are set to have the same shape and parameters to reduce installation difficulty. 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 direction of the main mode electric field.
[0064] In an optional embodiment, the dielectric resonator 2 is provided with at least one external chamfer 6. In this embodiment, the conductive ring 3 is provided with an external chamfer corresponding to the outer contour of the dielectric resonator 2 to achieve structural uniformity and aesthetic appearance. In this embodiment, the external chamfer 6 is used to mark the shape of the dielectric resonator 2, thereby facilitating the positioning and installation of the dielectric resonator 2.
[0065] Embodiments of this disclosure provide a dual-mode filter, including a first resonator and a second resonator; the first resonator is a dual-mode resonator 10 as described in any of the foregoing embodiments; the first resonator and the second resonator are connected in series through a coupling structure.
[0066] By adding input-output coupling structures to the two metal cavities of the dual-mode dielectric resonator 2, a dual-mode filter can be directly constructed, as shown in Figures 6 and 7. The input and output ports 7 of the filter are set on the metal cavities of the dual-mode dielectric resonator 2 and are in the form of coupling rings 9. The input and output ports 7 are coupled to the two orthogonal modes of the dual-mode dielectric resonator 2 respectively, forming a filter with two transmission poles. Its topology is shown in Figure 11, and the transmission and reflection curves are shown in Figure 12.
[0067] In an optional embodiment, the second resonator is a coaxial resonator 11 or the dual-mode resonator 10 described above.
[0068] Based on the above filter example, two dual-mode resonators 10 are used in combination to obtain a dual-mode filter.
[0069] Specifically, in this embodiment, two dual-mode resonators 10 are cascaded to form 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 constitute an integrated coupling cavity, the structure of which is shown in Figures 6 and 7. The input and output structure of the filter adopts the structure of a coupling loop 9, and electromagnetic coupling is performed through the openings in the connected metal walls of the dual-mode resonators 10, the topology of which is shown in Figure 13, and the transmission and reflection curves are shown in Figure 14.
[0070] It should be noted that in this embodiment, the second resonator is also a dual-mode resonator 10, but it is not limited to dual-mode resonator 10. It can also be cascaded with other types of resonators to form a hybrid mode filter. Figures 8 and 9 show the hybrid coupling filter structure of dual-mode dielectric resonator 2 and coaxial resonator 11. Its input port and output port are directly connected to coaxial resonator 11. Coaxial resonator 11 is electromagnetically coupled to dielectric dual-mode resonator 10 through coupling window 8 structure. Its topology is shown in Figure 13, and the filter transmission and reflection curves are shown in Figure 14.
[0071] In an optional implementation, the number of the first resonators is multiple, and the number of the second resonators is multiple.
[0072] Hybrid-coupled filters offer flexible input and output structures, providing significant advantages for the design and production of dual-mode filters. By cascading more dual-mode dielectric resonators or other types of resonators, filters with more transmission zeros can be implemented, achieving higher suppression and transmission characteristics.
[0073] The combined circuit of two filters operating in different frequency bands can be used as a frequency division duplexer. Therefore, the dielectric multimode resonator obtained by the modified structure in this embodiment can also be applied in duplexer and multiplexer products.
[0074] Embodiments of this disclosure also provide a multiplexer that includes a two-mode filter.
[0075] The dual-mode resonator 10 and dual-mode filter provided in the embodiments of this disclosure achieve dual-mode resonance by setting conductive rings 3 and metal cavities 1 on both sides of the dielectric resonator 2. The conductive rings 3 and metal cavities 1 constitute a resonant cavity. The overall volume is small, the space utilization rate is high, and it is easy to manufacture.
[0076] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this disclosure, and are not intended to limit them. Although this disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this disclosure. Industrial applicability
[0077] The dual-mode resonator, dual-mode filter, and multiplexer disclosed herein achieve dual-mode resonance by placing conductive rings and metal cavities on opposite sides of a dielectric resonator. The conductive rings and metal cavities constitute a resonant cavity. The overall size is small, space utilization is high, and it is easy to manufacture.
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 disposed on opposite sides of the dielectric resonator; The openings of both the first cavity and the second cavity are oriented towards the dielectric resonator; A conductive ring is provided 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 less than the dielectric constant of the dielectric resonator; The dielectric constant of the second cavity is less than the dielectric constant of the dielectric resonator.
2. The dual-mode resonator according to claim 1, characterized in that, The conductive ring has at least one incised angle inside, which can change the main resonant frequency and the direction of the main mode electric field in the resonant cavity. The shape of the inscribed angle is one of a polygon, a sector, or an arc, or a combination of several shapes.
3. The dual-mode resonator according to claim 1 or 2, characterized in that, The number of inscribed angles is two, and the two inscribed angles are set opposite to each other.
4. The dual-mode resonator according to claim 3, characterized in that, The two inscribed angles have the same shape.
5. The dual-mode resonator according to claim 3, characterized in that, The two inscribed angles have different shapes.
6. The dual-mode resonator according to claim 1, characterized in that, A conductive layer is provided on the outer wall of the dielectric resonator.
7. The dual-mode resonator according to claim 6, characterized in that, The conductive ring and the conductive layer are connected.
8. The dual-mode resonator according to any one of claims 1-7, characterized in that, The first cavity is a metal cavity; And / or, the second cavity is a metal cavity.
9. The dual-mode resonator according to any one of claims 1-8, characterized in that, The cross-sectional shape of the outer contour of the dielectric resonator is polygonal or circular.
10. The dual-mode resonator according to any one of claims 2-9, characterized in that, The dielectric resonator has at least one external tangent.
11. The dual-mode resonator according to any one of claims 4-10, characterized in that, The first cavity and the second cavity are welded to the conductive layer of the dielectric resonator.
12. The dual-mode resonator according to any one of claims 4-11, characterized in that, The conductive layer and conductive ring of the dielectric resonator are attached to the surface of the dielectric resonator using a back silvering or electroplating process.
13. The dual-mode resonator according to any one of claims 1-12, characterized in that, The dielectric resonator is made of a ceramic material with a dielectric constant of 15-85.
14. A dual-mode filter, characterized in that, Includes a first resonator and a second resonator; The first resonator is the dual-mode resonator according to any one of claims 1-13; The first resonator and the second resonator are connected in series through a coupling structure.
15. The dual-mode filter according to claim 14, characterized in that, The second resonator is a coaxial resonator or a dual-mode resonator as described in any one of claims 1-13.
16. The dual-mode filter according to claim 14 or 15, characterized in that, The number of the first resonator is multiple, and the number of the second resonator is multiple.
17. A multiplexer, characterized in that, Includes the dual-mode filter as described in any one of claims 14-16.