Resonator structure and filter thereof

Abstract

The utility model relates to a resonator structure and a filter thereof. The resonator structure comprises a body. The resonant cavity unit comprises a first resonant cavity and a second resonant cavity which are sequentially arranged on the body in the first direction, the first resonant cavity comprises a first resonant hole, the second resonant cavity comprises a second resonant hole, and the first resonant hole and the second resonant hole are located in the same surface of the body; the resonant cavity unit further comprises a third resonant hole, the third resonant hole is formed in the side face of the body, and the third resonant hole is located between the first resonant cavity and the second resonant cavity; the first resonance hole, the second resonance hole and the third resonance hole are matched to form a three-cavity cross coupling structure, a transmission zero point playing a role in enhancing an inhibition effect can be formed at a high-frequency stop band of a filter passband, the size and the volume of the resonator can be effectively reduced, the required installation space is reduced, and the cost is reduced. While the volume is reduced, the suppression of a certain frequency band or frequency point of a high-frequency stop band is enhanced.

Description

Technical Field

[0001] This utility model relates to the field of communication equipment technology, and in particular to a resonator structure and its filter. Background Technology

[0002] Ceramic waveguide filters are microwave filters made of ceramic materials, primarily used for signal processing in the radio frequency (RF) and microwave bands. Their high dielectric constant and low loss characteristics make them excellent for high-frequency applications. Two-cavity filters are a common microwave filter design, consisting of two resonant cavities that achieve signal filtering through a coupling mechanism. This structure is simple and easy to tune, and is widely used in RF and microwave systems. Two-cavity filters are widely used in RF and microwave fields due to their simplicity, flexibility, and high selectivity. Although they have a narrower bandwidth and require high manufacturing precision, their excellent performance makes them an ideal choice for many high-frequency signal processing systems. The suppression effect of a filter is usually directly related to its design order. A two-cavity structure is equivalent to a second-order filter, the lowest order filter structure. In filter design, to increase the filter's out-of-band suppression effect, the passband order is increased, or cross-coupling is added while keeping the order constant. Cross-coupling involves adding coupling between non-adjacent resonant cavities, and a minimum of three resonant cavities are required to form cross-coupling.

[0003] However, the shortcomings of existing technologies are that while higher filter orders result in better suppression, they also increase the filter's size. Therefore, there is an urgent need to design a filter that can simultaneously balance size, multiple resonant modes, and good suppression performance. Utility Model Content

[0004] Therefore, the technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a resonator structure and its filter, which can form a transmission zero at the high-frequency stopband of the filter passband to enhance the suppression effect, and can effectively reduce the size and volume of the resonator and reduce the installation space required.

[0005] To solve the above-mentioned technical problems, this utility model provides a resonator structure, including,

[0006] ontology;

[0007] A resonant cavity unit includes a first resonant cavity and a second resonant cavity sequentially disposed along a first direction on the body. The first resonant cavity includes a first resonant aperture, and the second resonant cavity includes a second resonant aperture. The first resonant aperture and the second resonant aperture are located on the same surface of the body. The resonant cavity unit also includes a third resonant aperture, which is disposed on the side of the body and located between the first resonant cavity and the second resonant cavity. The first resonant aperture, the second resonant aperture, and the third resonant aperture cooperate to form a three-cavity cross-coupled structure.

[0008] A coupling unit is disposed in the body and located between the first resonant cavity and the second resonant cavity to adjust the coupling amount between the first resonant cavity and the second resonant cavity; the input signal enters the first resonant cavity, is transmitted to the second resonant cavity through the coupling mechanism, and then outputs an output signal.

[0009] In one embodiment of the present invention, the body has opposing first and second surfaces along the thickness direction; the body also has opposing first and second side surfaces, the first and second side surfaces extending along the first direction.

[0010] In one embodiment of the present invention, the first resonant hole and the second resonant hole are spaced apart on the first surface along the first direction, the third resonant hole is disposed on the first side surface, and the depth direction of the third resonant hole is the second direction.

[0011] In one embodiment of the present invention, the coupling unit includes an isolation groove disposed on the second side and located between the first resonant hole and the second resonant hole, so as to adjust the coupling amount between the first resonant hole and the second resonant hole.

[0012] In one embodiment of this utility model, the projection of the isolation groove along the second direction completely overlaps or partially overlaps with the projection of the third resonant hole along the second direction.

[0013] In one embodiment of the present invention, the coupling unit includes an adjustment hole disposed on the first surface and located between the first resonant hole and the second resonant hole, so as to adjust the coupling amount between the first resonant hole and the second resonant hole.

[0014] In one embodiment of this utility model, the projections of the first resonant hole and the second resonant hole along the thickness direction of the body are circular, square, elliptical, or irregular polygonal.

[0015] In one embodiment of this utility model, the depths of the first resonant hole and the second resonant hole are different.

[0016] In one embodiment of this utility model, the first resonant hole, the second resonant hole, and the third resonant hole are all blind holes.

[0017] This invention also provides a filter, including at least one resonator structure as described above.

[0018] The above-mentioned technical solution of this utility model has the following advantages compared with the prior art:

[0019] The resonator structure of this utility model includes a body, a resonant cavity unit, and a coupling unit. The resonant cavity unit includes a first resonant cavity and a second resonant cavity sequentially disposed on the body. The first resonant cavity includes a first resonant aperture, and the second resonant cavity includes a second resonant aperture. The first resonant aperture and the second resonant aperture are disposed on the same surface of the body. The coupling unit is disposed on the body and is located between the first resonant cavity and the second resonant cavity to adjust the coupling amount between the first resonant cavity and the second resonant cavity. In addition, the resonant cavity unit also includes a third resonant aperture, which is disposed on the side of the body and is also located between the first resonant cavity and the second resonant cavity.

[0020] This configuration creates a transmission zero at the high-frequency stopband of the filter passband, which enhances the suppression effect. Compared with the prior art, this invention can effectively reduce the size and volume of the resonator, thereby reducing the required installation space. While reducing the size, it also enhances the suppression of a certain frequency band or frequency point in the high-frequency stopband. Attached Figure Description

[0021] To make the content of this utility model easier to understand, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0022] Figure 1 This is a first-view schematic diagram of the overall structure of a preferred embodiment of the present invention.

[0023] Figure 2 This is a second-view schematic diagram of the overall structure of a preferred embodiment of the present invention.

[0024] Figure 3 This is a third-view schematic diagram of the overall structure of a preferred embodiment of the present invention.

[0025] Figure 4 This is a schematic diagram of the overall structure of another embodiment of the present invention.

[0026] Figure 5This is a simulation curve and theoretical coupling structure diagram of the resonator structure of the preferred embodiment of this utility model at 4000MHz, showing the cross-coupling design.

[0027] Explanation of reference numerals in the accompanying drawings: 100, first surface; 200, second surface; 300, first side surface; 400, second side surface; 1, first resonant cavity; 10, first resonant aperture; 2, second resonant cavity; 20, second resonant aperture; 30, third resonant aperture; 4, coupling unit. Detailed Implementation

[0028] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments are not intended to limit the present invention.

[0029] A ceramic waveguide filter is a frequency-selective filter that utilizes a waveguide structure made of ceramic material. It achieves its filtering function by leveraging the electromagnetic wave propagation characteristics of the waveguide. In material selection, ceramic materials with suitable dielectric constants and low losses are chosen based on frequency requirements. The waveguide structure is fabricated through dry pressing, precision machining, or injection molding. High-temperature sintering densifies the ceramic blank, and a conductive material is coated onto the inner wall of the ceramic blank to allow electromagnetic waves to propagate within the waveguide cavity. Multiple resonant cavities are assembled to form a complete filter structure. Finally, testing and tuning are performed to ensure the filter performance meets design requirements. Example 1

[0030] Reference Figures 1 to 3 As shown, this utility model discloses a resonator structure, including a body;

[0031] The resonator structure further includes a resonant cavity unit, which includes a first resonant cavity 1 and a second resonant cavity 2 sequentially disposed on the body along a first direction. The first resonant cavity 1 includes a first resonant hole 10, and the second resonant cavity 2 includes a second resonant hole 20. The first resonant hole 10 and the second resonant hole 20 are located on the same surface of the body.

[0032] The resonant cavity unit further includes a third resonant aperture 30, which is disposed on the side of the body and located between the first resonant cavity 1 and the second resonant cavity 2. This allows for the excitation of a third resonant mode in the dual-cavity structure. Based on the physical shape and size of the two cavities, three transmission modes are achieved, resulting in the performance of a third-order filter. In principle, when a third resonant cavity exists between the first and second resonant cavities, the signal transmission path changes from the simple path from the first to the second resonant cavity to two paths simultaneously: from the first to the second resonant cavity and from the first resonant cavity to the third resonant cavity and back to the second resonant cavity. Because signal coupling also occurs between the first and second resonant cavities during the transmission from the first to the third resonant cavity and back to the second resonant cavity, a cross-coupling phenomenon occurs, resulting in a zero point on the right side. Figure 5 The notch point mentioned above can be used to enhance suppression. Specifically, when the first resonant aperture and the second resonant aperture are on the same plane, the first resonant aperture couples with the third resonant aperture, the third resonant aperture couples with the second resonant aperture, and the coupling polarities of the first resonant aperture and the second resonant aperture are the same. In this case, the cross-coupling zero point is on the right side (i.e., the high-frequency end).

[0033] The resonator structure further includes a coupling unit 4, which is disposed on the body and located between the first resonant cavity 1 and the second resonant cavity 2, so as to adjust the coupling amount between the first resonant cavity 1 and the second resonant cavity 2.

[0034] With this configuration, the first resonant aperture 10, the second resonant aperture 20, the third resonant aperture 30, and the coupling unit 4 cooperate to form a three-cavity cross-coupled structure. During operation, the input signal enters the first resonant cavity 1, is transmitted to the second resonant cavity 2 through the coupling mechanism, and then outputs an output signal.

[0035] Therefore, it can be understood that the resonator structure protected by this utility model includes a body, a resonant cavity unit, and a coupling unit. The resonant cavity unit includes a first resonant cavity and a second resonant cavity sequentially disposed on the body. The first resonant cavity includes a first resonant hole, and the second resonant cavity includes a second resonant hole. The first and second resonant holes are disposed on the same surface of the body. The coupling unit is disposed on the body and is located between the first and second resonant cavities to adjust the coupling amount between the first and second resonant cavities. In addition, the resonant cavity unit also includes a third resonant hole, which is disposed on the side of the body and is also located between the first and second resonant cavities. This arrangement can form a transmission zero at the high-frequency stopband of the filter passband, which can enhance the suppression effect. Compared with the prior art, this utility model can effectively reduce the size and volume of the resonator, thereby reducing the required installation space. While reducing the size, it also enhances the suppression of a certain frequency band or frequency point in the high-frequency stopband.

[0036] In a preferred embodiment, the body has opposing first surfaces 100 and second surfaces 200 along the thickness direction; the body also has opposing first side surfaces 300 and second side surfaces 400, the first side surface 300 and the second side surface 400 extending along the first direction.

[0037] In detail, the shapes of the first resonant cavity 1 and the second resonant cavity 2 can be polygons, cubes, or irregularly shaped cubes. In this embodiment, both the first resonant cavity 1 and the second resonant cavity 2 are cuboids.

[0038] Furthermore, the first resonant hole 10 and the second resonant hole 20 are spaced apart on the first surface 100 along the first direction, and the third resonant hole 30 is disposed on the first side surface 300, with the depth direction of the third resonant hole 300 defined as the second direction.

[0039] The first resonant hole 10 and the second resonant hole 20 are blind holes formed by indentation along the first surface 100 to generate and tune the frequencies of the corresponding resonant cavities.

[0040] Furthermore, the shape and size of the third resonant hole 30 are not fixed. Theoretically, its design can meet a specific resonant frequency, and the coupling amount with the first resonant hole 10 and the second resonant hole 20 can conform to the design of the entire filter.

[0041] In a preferred embodiment, the coupling unit 4 includes an isolation groove 40, which is disposed on the second side 400 and located between the first resonant hole 10 and the second resonant hole 20, so as to adjust the coupling amount between the first resonant hole 10 and the second resonant hole 20.

[0042] Specifically, the projection of the isolation groove 40 along the second direction completely overlaps or partially overlaps with the projection of the third resonant hole 30 along the second direction.

[0043] In detail, the amount of coupling between the first resonant hole 10 and the third resonant hole 10, and the amount of coupling between the second resonant hole 20 and the third resonant hole 30, can be adjusted by the distance between the third resonant hole 30 and the first resonant hole 10 and the second resonant hole 20, or by the size of the hole itself.

[0044] In other embodiments, when the coupling amount between the first resonant hole 10 and the second resonant hole 20 is insufficient, the coupling amount between the first resonant hole 10 and the second resonant hole 20 can be increased by providing an adjustment hole 41 on the first surface 100. (Refer to...) Figure 3 As shown, the adjustment hole 41 is disposed on the first surface 100, and the adjustment hole 41 is located between the first resonant hole 10 and the second resonant hole 20 to adjust the coupling amount between the first resonant hole 10 and the second resonant hole 20.

[0045] It should be noted that the projections of the first resonant hole 10 and the second resonant hole 20 along the thickness direction of the body can be circular, square, elliptical, or irregular polygonal.

[0046] The first resonant hole 10 and the second resonant hole 20 have different depths.

[0047] In a preferred embodiment, the first resonant hole 10, the second resonant hole 20, and the third resonant hole 30 are all blind holes.

[0048] Combination Figure 5 The figure shows the simulation curve and theoretical coupling structure diagram of the resonator structure of this invention at 4000MHz, which demonstrates the cross-coupling design. It can be seen that the suppression at 4000MHz can reach -78.4dB.

[0049] The transmission zero of a dielectric filter is generated by the cross-coupling path of a non-adjacent resonant cavity, which superimposes the signal in opposite phase with the signal in the main coupling path, thereby blocking the signal at a specific frequency outside the passband and forming a transmission zero. This invention can form a transmission zero at the high-frequency stopband of the filter passband, which enhances the suppression effect. Example 2

[0050] This invention also discloses a filter, including at least one resonator structure as described in Embodiment 1.

[0051] The filter employing the above resonator structure can form a transmission zero at the high-frequency stopband of the filter passband, which enhances the suppression effect; and can effectively reduce the size and volume of the filter, saving materials and reducing manufacturing costs.

[0052] In the description of this utility model, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0053] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0054] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A resonator structure, characterized in that: include, ontology; A resonant cavity unit includes a first resonant cavity and a second resonant cavity sequentially disposed along a first direction on the body. The first resonant cavity includes a first resonant aperture, and the second resonant cavity includes a second resonant aperture. The first resonant aperture and the second resonant aperture are located on the same surface of the body. The resonant cavity unit also includes a third resonant aperture, which is disposed on the side of the body and located between the first resonant cavity and the second resonant cavity. The first resonant aperture, the second resonant aperture, and the third resonant aperture cooperate to form a three-cavity cross-coupled structure. A coupling unit is disposed in the body and located between the first resonant cavity and the second resonant cavity to adjust the coupling amount between the first resonant cavity and the second resonant cavity; the input signal enters the first resonant cavity, is transmitted to the second resonant cavity through the coupling mechanism, and then outputs an output signal; The body has a first surface and a second surface opposite each other along the thickness direction; the body also has a first side surface and a second side surface opposite each other, the first side surface and the second side surface extending along the first direction; The first resonant hole and the second resonant hole are spaced apart on the first surface along the first direction, and the third resonant hole is disposed on the first side surface, with the depth direction of the third resonant hole being the second direction; The coupling unit includes an isolation groove disposed on the second side and located between the first resonant hole and the second resonant hole to adjust the coupling amount between the first resonant hole and the second resonant hole; The projection of the isolation groove along the second direction completely overlaps or partially overlaps with the projection of the third resonant hole along the second direction. The coupling unit includes an adjustment hole disposed on the first surface and located between the first resonant hole and the second resonant hole, so as to adjust the coupling amount between the first resonant hole and the second resonant hole.

2. The resonator structure according to claim 1, characterized in that: The projections of the first resonant hole and the second resonant hole along the thickness direction of the body are circular, square, elliptical, or irregular polygonal.

3. A resonator structure according to claim 1, characterized in that: The first resonant hole and the second resonant hole have different depths.

4. A resonator structure according to any one of claims 1-3, characterized in that: The first resonant hole, the second resonant hole, and the third resonant hole are all blind holes.

5. A filter, characterized in that: It includes at least one resonator structure as described in any one of claims 1-4.

Images