Electromagnetic hybrid coupling structure, filter and multiplexer

Abstract

The utility model provides an electromagnetic hybrid coupling structure, which is arranged in a filter and comprises a dielectric plate, an electric coupling plate, a first coupling screw rod, a first metal arc-shaped plate, a second metal arc-shaped plate and two resonators, the metal layer surface of the dielectric plate is provided with a coupling gap; the electric coupling plate is fixedly arranged in the coupling gap, and two ends of the electric coupling plate are respectively connected with the first metal arc-shaped plate and the second metal arc-shaped plate; the first metal arc-shaped plate and the second metal arc-shaped plate are symmetrically distributed relative to the first coupling screw rod; each resonator and the first metal arc-shaped plate or the second metal arc-shaped plate are coaxially arranged in the filter, and the resonators are connected through coupling connecting ribs to form a magnetic coupling structure. According to the utility model, the electric coupling structure and the magnetic coupling structure are independently arranged, so that the electric coupling strength and the magnetic coupling strength can be correspondingly debugged by respectively adjusting the sizes and the positions of the first coupling screw rod and the coupling rib in the debugging process.

Description

Technical Field

[0001] This utility model belongs to the field of microwave filter technology for line communication, and particularly relates to an electromagnetic hybrid coupling structure, filter and multiplexer. Background Technology

[0002] With the rapid development of modern wireless communication technology, radio spectrum resources have become increasingly crowded and precious. In order to fully optimize spectrum resource utilization and reduce interference, microwave filters with high frequency selectivity play a crucial role. Metal coaxial cavity filters are widely used in microwave wireless communication systems due to their advantages such as high reliability, low insertion loss (high Q value), large power capacity, good heat dissipation characteristics, mature manufacturing process, and simple debugging.

[0003] Out-of-band rejection (OBS) is an important electrical performance indicator for filters. It can typically be improved by increasing the filter's order and introducing transmission zeros. However, increasing the filter's order often leads to larger dimensions and insertion loss, as well as increased cost and design complexity.

[0004] Introducing transmission zeros to improve the out-of-band rejection of a filter without increasing its order is the most widely used method. Unlike the traditional method of creating transmission zeros by introducing cross-coupling between non-adjacent resonant elements, electromagnetic hybridization refers to the creation of new transmission zeros when both electrical and magnetic coupling paths exist simultaneously between two adjacent or non-adjacent resonant elements, with the electrical and magnetic coupling magnitudes being comparable. This process improves the filter's out-of-band rejection.

[0005] Currently, electromagnetic hybrid coupling is common in the design of planar filter structures such as microstrip, substrate integrated waveguide, and coplanar waveguide. However, its electromagnetic hybrid coupling structure is complex, difficult to debug, and unsuitable for mass production applications. How to improve the electromagnetic coupling structure to solve the debugging problem is an important direction for current filter development. Utility Model Content

[0006] To address the problem of how to improve the electromagnetic coupling structure and thus solve the debugging problem, as described in the background art, this utility model proposes the following technical solution:

[0007] An electromagnetic hybrid coupling structure, disposed within a filter, includes: a dielectric plate, an electrical coupling plate, a first coupling screw, a first arc-shaped metal plate, a second arc-shaped metal plate, and two resonators. The dielectric plate is detachably disposed at the open end of the filter. Two opposite wide surfaces of the dielectric plate are respectively provided with metal layers, and a coupling notch is provided on the surface of the metal layer near the filter. The electrical coupling plate is fixedly disposed within the coupling notch, and its two ends are respectively connected to the first arc-shaped metal plate and the second arc-shaped metal plate. One end of the first coupling screw passes through the coupling notch and enters the filter. The first and second arc-shaped metal plates are symmetrically distributed about the first coupling screw. Each resonator is coaxially disposed within the filter with either the first or second arc-shaped metal plate, and the resonators are connected by coupling ribs to form a magnetic coupling structure.

[0008] The openings of the first metal arc plate and the second metal arc plate are arranged facing each other, and the diameter of the first metal arc plate is larger than the diameter of the resonator.

[0009] Furthermore, each of the resonators is provided with a resonant cavity, and there is a coupling interval between the open end of each of the resonators and the coupling notch.

[0010] Furthermore, the coupling notch is provided with a plurality of mounting holes for fixing the second coupling screw, and each of the mounting holes is symmetrical about the first coupling screw.

[0011] Furthermore, each of the resonators has an electroplated protective layer on its outer peripheral surface.

[0012] Furthermore, the electrical coupling plate divides the coupling gap into a left side portion and a right side portion, and the orthogonal projection area of ​​each resonator on the dielectric plate is smaller than the area of ​​the left side portion or the area of ​​the right side portion.

[0013] Furthermore, there is a coupling gap between the electrical coupling plate and the metal layer.

[0014] Another objective of this invention is to provide a filter comprising: a base and a plurality of the aforementioned electromagnetic hybrid coupling structures; the base having an open filter cavity, one side of each electromagnetic hybrid coupling structure being detachably connected to the bottom surface of the filter cavity, and the other side of each electromagnetic hybrid coupling structure being detachably connected to the open end of the base; connectors are respectively provided on both sides of the base, and each electromagnetic hybrid coupling structure is fixedly connected to each other to close the filter cavity.

[0015] Furthermore, each of the electromagnetic hybrid coupling structures is arranged sequentially along the length of the base within the filter cavity, and adjacent electromagnetic hybrid coupling structures are connected to each other via the coupling ribs on the side closest to the filter cavity.

[0016] Another objective of this invention is to provide a multiplexer comprising multiple electromagnetic coupling structures as described above.

[0017] Beneficial effects: By independently setting up the electric coupling structure and the magnetic coupling structure, the electric coupling strength and the magnetic coupling strength can be adjusted during the debugging process by adjusting the size and position of the first coupling screw and the coupling rib, respectively. Attached Figure Description

[0018] Figure 1 This is an exploded structural diagram of an electromagnetic hybrid coupling structure according to an embodiment of the present invention;

[0019] Figure 2 This is a schematic diagram of the exploded structure of the dielectric plate according to an embodiment of the present invention;

[0020] Figure 3 This is a cross-sectional schematic diagram of an electromagnetic hybrid coupling structure according to an embodiment of the present utility model;

[0021] Figure 4 This is a perspective structural diagram of a filter according to an embodiment of the present utility model;

[0022] Figure 5 This is a frequency response diagram of a filter according to an embodiment of the present invention, which generates a transmission zero at the low end of the passband.

[0023] Figure 6 This is a frequency response diagram of a filter according to an embodiment of the present invention, which generates a transmission zero at the high end of the passband.

[0024] Figure 7 A perspective view of another filter according to an embodiment of the present invention. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this application clearer, the present invention will be described in further detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the scope of the present invention.

[0026] It should be understood that the terms “center,” “upper,” “lower,” “front,” “back,” “left,” “right,” “vertical,” “horizontal,” “top,” “bottom,” “inner,” and “outer,” etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this patent 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 patent.

[0027] Figure 1 This is an exploded structural diagram of an electromagnetic hybrid coupling structure according to an embodiment of the present invention.

[0028] Reference Figure 1 An electromagnetic hybrid coupling structure according to an embodiment of the present invention includes: a dielectric plate 2, an electrical coupling plate 3, a first coupling screw 4, a first metal arc plate 5, a second metal arc plate 6, and two resonators 7. The dielectric plate 2 is detachably disposed at the open end of the filter 1 via a connector. Metal layers 21 are respectively provided on two opposite wide surfaces of the dielectric plate 2. A coupling notch 22 is provided on the metal layer 21 near the filter 1. The electrical coupling plate 3 is disposed within the coupling notch 22, and its two ends are respectively connected to the first metal arc plate 5 and the second metal arc plate 6, thereby forming an integrated electrical coupling structure. The first coupling screw 4 passes through the electrical coupling plate 3 and enters the filter 1. Each resonator 7 is coaxially disposed within the filter 1 with either the first metal arc plate 5 or the second metal arc plate 6. The resonators 7 are connected by coupling ribs 8 to form a magnetic coupling structure.

[0029] Figure 2 This is a schematic diagram of the exploded structure of the dielectric plate according to an embodiment of the present invention. Figure 3 This is a cross-sectional schematic diagram of an electromagnetic hybrid coupling structure according to an embodiment of the present invention.

[0030] Refer to together Figure 2 and Figure 3 Specifically, the first metal arc plate 5 and the second metal arc plate 6 are symmetrically distributed about the first coupling screw 4 on the wide surface of the dielectric plate 2. This symmetrical design helps to ensure the uniformity of electromagnetic coupling. To further enhance the electromagnetic coupling effect, the openings of the first metal arc plate 5 and the second metal arc plate 6 are arranged facing each other, and the diameter of the first metal arc plate 5 is larger than the diameter of the resonator 7. Each resonator 7 has a resonant cavity 71, and there is a coupling interval between the opening end of the resonator 7 and the coupling notch 22. The diameter of the resonator 7 is smaller than the diameter of either the first metal arc plate 5 or the second metal arc plate 6. Both the first metal arc plate 5 and the second metal arc plate 6 are open-circuit structures. The electrical coupling strength between the two resonators 7 can be adjusted by changing the diameters of the first metal arc plate 5 and the second metal arc plate 6.

[0031] Furthermore, the coupling notch 22 is provided with multiple mounting holes 23 for fixing the second coupling screw 9, and the mounting holes 23 are symmetrical about the first coupling screw 4. Each resonator 7 has an electroplated protective layer on its outer peripheral surface, which prevents the resonator 7 from being affected by the external environment and improves its stability and reliability. The electrical coupling plate 3 divides the coupling notch 22 into a left side and a right side, and the orthogonal projection area of ​​each resonator 7 on the dielectric plate 2 is smaller than the area of ​​the left or right side. The end of the second coupling screw 9 enters the resonant cavity 71 of the resonator 7 through the mounting hole 23. During the design of the filter 1, the magnetic coupling strength between the two resonators 7 can be changed by adjusting the depth of the second coupling screw 9 entering the resonant cavity 71. During the design process, the magnetic coupling strength between the two resonators 7 can also be further changed by changing the height of the coupling rib 8.

[0032] Figure 4 This is a perspective structural diagram of a filter according to an embodiment of the present invention.

[0033] Reference Figure 4 Another objective of this invention is to provide a filter 1, comprising: a base and multiple electromagnetic hybrid coupling structures as described above. The base has an open filter cavity 12, and both sides of the base are connected to connectors 13 to receive external signals. One side of each electromagnetic hybrid coupling structure is detachably connected to the open side of the base via screws or other connectors, and the other side of each electromagnetic hybrid coupling structure is detachably connected to the bottom surface of the filter cavity 12 via bolts or other connectors. The sides of each electromagnetic hybrid coupling structure furthest from the filter cavity 12 are fixedly connected, and the sides of each electromagnetic hybrid coupling structure closest to the filter cavity 12 are fixedly connected via coupling ribs 8, thereby forming an integrated structure and enclosing the filter cavity 12.

[0034] To further illustrate the specific structure and advantages of this application, the following description uses filters 1 with single electromagnetic hybrid coupling structures and multiple electromagnetic hybrid coupling structures as examples:

[0035] Figure 5 This is a frequency response diagram of a filter according to an embodiment of the present invention, which generates a transmission zero at the low end of the passband. Figure 6 This is a frequency response diagram of a filter according to an embodiment of the present invention, which generates a transmission zero at the high end of the passband.

[0036] Example 1:

[0037] In this embodiment, there is only one electromagnetic hybrid coupling structure. After the dielectric substrate 2 is fixed to the base surface with metal screws, the filter cavity 12 is sealed, and both electrical and magnetic coupling paths exist between the two resonators 7. That is, both electrical and magnetic coupling exist between the two resonators 7 simultaneously. (Refer to...) Figure 5 When the electrical coupling and magnetic coupling between the two resonators 7 are of similar magnitude, and the electrical coupling is greater than the magnetic coupling, a transmission zero will be generated at a low frequency outside the passband of filter 1. (Refer to...) Figure 6 When the electrical and magnetic coupling between the two resonators 7 are of similar magnitude, and the magnetic coupling between the two resonators 7 is greater than the electrical coupling, a transmission zero will be generated at a high frequency outside the passband of filter 1. The adjustment methods for the electrical and magnetic coupling have been explained in detail above and will not be repeated here.

[0038] Figure 7 A perspective view of another filter according to an embodiment of the present invention.

[0039] Example 2:

[0040] Reference Figure 7 Unlike Embodiment 1, this embodiment uses two electromagnetic hybrid coupling structures, which, when installed within the base, form a linear fourth-order coaxial cavity filter 1. The filter 1 in this embodiment incorporates two electromagnetic hybrid coupling structure units, generating two transmission zeros. In other embodiments, there can be three, four, five, or more integer numbers of electromagnetic hybrid coupling structures, each located within a separate filter path; further details are omitted here. Furthermore, this invention can also be applied to filters with coaxial cavities, including but not limited to linear coaxial cavity filters and cross-coupled coaxial cavity filters.

[0041] Another objective of this invention is to provide a multiplexer comprising multiple electromagnetic hybrid coupling structures as described above. Each electromagnetic hybrid coupling structure is located within a filter, and each port of the multiplexer is provided with a filter, with each filter containing a corresponding electromagnetic hybrid coupling structure. The multiplexer includes, but is not limited to, duplexers, tripplexers, quadplexers, and other signal multiplexing devices with multiple ports; the specific number of ports is selected based on the performance requirements of the device.

[0042] In summary, by independently setting up the electrical coupling structure and the magnetic coupling structure, the electrical coupling strength and the magnetic coupling strength can be adjusted during the debugging process by adjusting the size and position of the first coupling screw and the coupling rib, respectively.

[0043] The above description describes specific embodiments of the utility model. Other embodiments are within the scope of the appended claims.

[0044] The terms “exemplary,” “example,” etc., used throughout this specification mean “serving as an example, instance, or illustration” and do not imply “preferred” or “advantageous” than other embodiments. Detailed descriptions are included for the purpose of providing an understanding of the described techniques. However, these techniques can be practiced without these detailed descriptions. In some instances, well-known structures and apparatuses are shown in block diagram form to avoid obscuring the concepts of the described embodiments.

[0045] The optional embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the embodiments of the present utility model are not limited to the specific details in the above embodiments. Within the scope of the technical concept of the embodiments of the present utility model, various simple modifications can be made to the technical solutions of the embodiments of the present utility model, and these simple modifications all fall within the protection scope of the embodiments of the present utility model.

[0046] The foregoing description of this specification is provided to enable any person skilled in the art to implement or use the content of this specification. Various modifications to the content of this specification will be apparent to those skilled in the art, and the general principles defined herein can be applied to other variations without departing from the scope of protection of this specification. Therefore, this specification is not limited to the examples and designs described herein, but is consistent with the widest scope of the principles and novel features disclosed herein.

Claims

1. An electromagnetic hybrid coupling structure, disposed within a filter (1), characterized in that, include: The filter comprises a dielectric substrate (2), an electrical coupling plate (3), a first coupling screw (4), a first metal arc plate (5), a second metal arc plate (6), and two resonators (7); the dielectric substrate (2) is detachably disposed at the open end of the filter (1), and the two opposite wide surfaces of the dielectric substrate (2) are respectively provided with metal layers (21), and the surface of the metal layer (21) near the filter (1) is provided with a coupling notch (22); the electrical coupling plate (3) is fixedly disposed in the coupling notch (22), and the two ends of the electrical coupling plate (3) are respectively connected to the first metal arc plate (6) and the second metal arc plate (7). The first metal arc plate (5) and the second metal arc plate (6) are connected; one end of the first coupling screw (4) passes through the coupling notch (22) and enters the filter (1); the first metal arc plate (5) and the second metal arc plate (6) are symmetrically distributed about the first coupling screw (4); each resonator (7) is coaxially arranged with the first metal arc plate (5) or the second metal arc plate (6) in the filter (1); the resonators (7) are connected by coupling ribs (8) to form a magnetic coupling structure.

2. The electromagnetic hybrid coupling structure according to claim 1, characterized in that, The openings of the first metal arc plate (5) and the second metal arc plate (6) are arranged facing each other, and the diameter of the first metal arc plate (5) is larger than the diameter of the resonator (7).

3. The electromagnetic hybrid coupling structure according to claim 2, characterized in that, Each of the resonators (7) has a resonant cavity (71) and there is a coupling interval between the open end of each of the resonators (7) and the coupling notch (22).

4. The electromagnetic hybrid coupling structure according to claim 3, characterized in that, The coupling notch (22) is provided with a plurality of mounting holes (23) for fixing the second coupling screw (9), and each mounting hole (23) is symmetrical about the first coupling screw (4).

5. An electromagnetic hybrid coupling structure according to claim 4, characterized in that, Each of the resonators (7) has an electroplated protective layer on its outer peripheral surface.

6. The electromagnetic hybrid coupling structure according to claim 4, characterized in that, The electrical coupling plate (3) divides the coupling gap (22) into a left side and a right side, and the orthogonal projection area of ​​each resonator (7) on the dielectric plate (2) is smaller than the area of ​​the left side or the area of ​​the right side.

7. An electromagnetic hybrid coupling structure according to claim 6, characterized in that, There is a coupling gap between the electrical coupling plate (3) and the metal layer (21).

8. A filter, characterized in that, include: The base (11) and the electromagnetic hybrid coupling structure as described in any one of claims 1 to 7; the base (11) is provided with an open filter cavity (12), one side of each electromagnetic hybrid coupling structure is detachably connected to the bottom surface of the filter cavity (12), and the other side of each electromagnetic hybrid coupling structure is detachably connected to the open end of the base (11); connectors (13) are respectively provided on both sides of the base (11), and each electromagnetic hybrid coupling structure is fixedly connected to each other to close the filter cavity (12).

9. A filter according to claim 8, characterized in that, Each of the electromagnetic hybrid coupling structures is arranged sequentially along the length of the base (11) within the filter cavity (12), and adjacent electromagnetic hybrid coupling structures are connected to each other on the side closest to the filter cavity (12) by the coupling ribs (8).

10. A multiplexer, characterized in that, It includes the electromagnetic hybrid coupling structure described in any one of claims 1 to 7.

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