A dielectric waveguide filter capable of realizing capacitive negative coupling

Abstract

The present invention provides a dielectric waveguide filter capable of realizing capacitive negative coupling, wherein the dielectric waveguide filter comprises at least three resonators, and a blind slot having a length greater than or equal to half the wavelength of the dielectric waveguide filter is arranged between two resonators at the cross-coupling poles in the same cavity, so that the coupling characteristics between the two resonators are reversed, thereby realizing capacitive negative coupling. Preferably, the upper surface, the lower surface and / or each side surface of the blind slot are provided with an unplated area in a shape such as a bow shape, a W shape, an H shape, an M shape, etc., thereby realizing capacitive negative coupling between the two resonators. Thus, the dielectric waveguide filter of the present invention can realize capacitive negative coupling only through a conventional inductive coupling window structure, can improve the frequency selection characteristics and out-of-band suppression characteristics of the dielectric waveguide filter, and has the characteristics of simple implementation and convenient debugging.

Description

Technical Field

[0001] The present invention relates to dielectric waveguide filter technology in the field of communication technology, and in particular to a dielectric waveguide filter capable of realizing capacitive negative coupling. Background Art

[0002] With the continuous development of modern communication technology, the performance requirements for filters are getting higher and higher. Dielectric waveguide filters have been well applied in miniaturized and highly integrated communication systems due to their small size, high Q value, and low cost. However, with the continuous development of multi-frequency systems, the requirements for the frequency selection characteristics and out-of-band suppression characteristics of filters are also getting higher and higher. Introducing capacitive coupling is an important method to improve the frequency selection characteristics and out-of-band suppression characteristics of filters. The most common method to achieve capacitive coupling is to introduce metal coupling probes. However, for dielectric waveguide filters, it is more difficult to introduce coupling probes. At present, there is no mature technical solution for introducing coupling probes in dielectric waveguide filters.

[0003] In summary, the prior art obviously has inconveniences and defects in practical use, so it is necessary to improve it. Summary of the invention

[0004] In view of the above-mentioned defects, the object of the present invention is to provide a dielectric waveguide filter capable of realizing capacitive negative coupling, which can achieve the required filter frequency characteristics and out-of-band suppression characteristics, and has the characteristics of simple implementation and convenient debugging.

[0005] In order to achieve the above object, the present invention provides a dielectric waveguide filter capable of realizing capacitive negative coupling, the dielectric waveguide filter comprising at least three resonators, wherein at least one blind slot having a length greater than or equal to half the wavelength of the dielectric waveguide filter is arranged between a first resonator and a second resonator at a cross-coupling pole in the same cavity, so that the coupling characteristics between the first resonator and the second resonator are reversed to realize capacitive negative coupling.

[0006] According to the dielectric waveguide filter of the present invention, the blind groove is of regular shape or irregular shape, and the blind groove is arranged on the side of the coupling window between the adjacent first resonator and the second resonator.

[0007] According to the dielectric waveguide filter of the present invention, the blind slot is an arcuate blind slot, an H-shaped blind slot, a W-shaped blind slot, an M-shaped blind slot or a trapezoidal blind slot.

[0008] According to the dielectric waveguide filter of the present invention, the overall length of the blind slot is greater than or equal to half the wavelength of the operating frequency of the dielectric waveguide filter.

[0009] According to the dielectric waveguide filter of the present invention, the blind slot and the frequency blind holes corresponding to the first resonator and the second resonator are placed together.

[0010] According to the dielectric waveguide filter of the present invention, the magnitude of the coupling amount of the dielectric waveguide filter is determined by the size of the blind slot; the larger the area of ​​the blind slot is, the larger the coupling amount is.

[0011] According to the dielectric waveguide filter of the present invention, the surface of the dielectric waveguide filter is covered with a metal plating layer.

[0012] According to the dielectric waveguide filter of the present invention, the upper surface, the lower surface and / or each side surface of the blind slot is provided with at least one non-electroplated area of ​​regular or irregular shape.

[0013] According to the dielectric waveguide filter of the present invention, the unplated area is circular, elliptical, square, diamond or trapezoidal.

[0014] According to the dielectric waveguide filter of the present invention, the magnitude of the coupling amount of the dielectric waveguide filter is determined by the size of the unplated area, and the larger the area of ​​the unplated area is, the larger the coupling amount is; and / or

[0015] The magnitude of the coupling amount of the dielectric waveguide filter is determined by the number of the unplated areas. The greater the number of the unplated areas, the greater the coupling amount.

[0016] The present invention proposes a structural form for introducing capacitive negative coupling in a dielectric waveguide filter. The dielectric waveguide filter includes at least three resonators. A blind slot with a length greater than or equal to half the wavelength of the dielectric waveguide filter is arranged between two resonators at the cross-coupling poles in the same cavity. The blind slot is preferably of regular or irregular shape and is arranged on the side of the coupling window between the two resonators, which can reverse the coupling characteristics between the two resonators, thereby realizing capacitive negative coupling. Preferably, the upper surface, lower surface and / or each side of the blind slot are provided with an unplated area of ​​regular or irregular shape such as bow-shaped, W-shaped, H-shaped, M-shaped, etc., thereby realizing capacitive negative coupling between the two resonators. In this way, the dielectric waveguide filter of the present invention can realize capacitive negative coupling only through a conventional inductive coupling window structure, which can improve the frequency selection characteristics and out-of-band suppression characteristics of the dielectric waveguide filter, and has the characteristics of simple implementation and convenient debugging. The present invention plays an important role in promoting the development of dielectric waveguide filters in modern miniaturized integrated communication systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1A schematic diagram of a model structure in which a bow-shaped blind slot is introduced between two resonators of a dielectric waveguide filter in the first embodiment of the present invention to realize capacitive negative coupling;

[0018] Figure 2 A schematic diagram of a model structure in which an H-shaped blind slot is introduced between two resonators of a dielectric waveguide filter in a second embodiment of the present invention to achieve capacitive negative coupling;

[0019] Figure 3 A schematic diagram of a model structure in which an M-shaped blind slot is introduced between two resonators of a dielectric waveguide filter in a third embodiment of the present invention to achieve capacitive negative coupling;

[0020] Figure 4 Schematic diagram of the model structure of introducing a W-shaped blind slot between two resonators of the dielectric waveguide filter in the fourth embodiment of the present invention to achieve capacitive negative coupling. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0022] It should be noted that references to "one embodiment", "embodiment", "example embodiment", etc. in this specification refer to the embodiment described, which may include specific features, structures or characteristics, but not every embodiment must include these specific features, structures or characteristics. In addition, such expressions do not refer to the same embodiment. Furthermore, when describing specific features, structures or characteristics in conjunction with an embodiment, whether or not there is an explicit description, it has been shown that it is within the knowledge of those skilled in the art to combine such features, structures or characteristics into other embodiments.

[0023] In addition, certain words are used in the specification and subsequent claims to refer to specific components or parts. Those with ordinary knowledge in the relevant field should understand that manufacturers can use different nouns or terms to refer to the same component or part. This specification and subsequent claims do not use differences in names as a way to distinguish components or parts, but use differences in the functions of components or parts as the criteria for distinction. "Including" and "including" mentioned throughout the specification and subsequent claims are open-ended terms and should be interpreted as "including but not limited to". In addition, the word "connected" here includes any direct and indirect electrical connection means. Indirect electrical connection means include connection through other devices.

[0024] The present invention proposes a structural form for introducing capacitive negative coupling in a dielectric waveguide filter 100. The dielectric waveguide filter includes at least three resonators. At least one blind slot (also called a blind hole) with a length greater than or equal to half the wavelength of the dielectric waveguide filter is set between the first resonator and the second resonator at the cross-coupling pole in the same cavity, so that the coupling characteristics between the first resonator and the second resonator are reversed, thereby realizing capacitive negative coupling. The blind slot is a regular shape or an irregular shape, and the blind slot is set on the side of the coupling window between the adjacent first resonator and the second resonator. Preferably, the upper surface, the lower surface and / or each side surface of the blind slot are provided with an unplated area in a shape such as a bow shape, a W shape, an H shape, an M shape, etc., thereby realizing capacitive negative coupling between the two resonators. Better yet, the surface of the dielectric waveguide filter is covered with a metal plating layer. The dielectric material of the dielectric waveguide filter can be an electrically conductive material such as ceramics.

[0025] Figure 1 The schematic diagram of the model structure of introducing a bow-shaped blind slot between two resonators of the dielectric waveguide filter in the first embodiment of the present invention to realize capacitive negative coupling. In the first embodiment of the present invention, the dielectric waveguide filter 100 includes six resonators, each of which can include a resonant cavity, a resonant column, and a frequency blind hole. In addition, the present invention selects to set at least one blind slot 30 with a length greater than or equal to half the wavelength of the dielectric waveguide filter 100 between the first resonator 10 and the second resonator 20 at the cross-coupling pole in the same cavity, that is, the overall length of the blind slot 30 is greater than or equal to half the wavelength of the working frequency of the dielectric waveguide filter 100, so that the coupling characteristics between the first resonator 10 and the second resonator 20 can be reversed, thereby realizing capacitive negative coupling. Preferably, the blind slot 30 is arranged on the side of the coupling window 40 between the first resonator 10 and the second resonator 20.

[0026] The dielectric waveguide filter 100 of the present invention utilizes the above structure, and can obtain capacitive negative coupling only through a conventional inductive coupling window structure, thereby improving the filter frequency characteristics and out-of-band suppression characteristics. In addition, the dielectric waveguide filter 100 of the present invention has the characteristics of simple implementation and easy debugging, and solves the problem that the capacitive coupling method is single and complex in the prior art.

[0027] Preferably, the blind groove 30 is of a regular shape or an irregular shape, and the blind groove 30 is disposed on the side of the coupling window 40 between the adjacent first resonator 10 and the second resonator 20. The blind groove 30 may be of any shape such as an arcuate blind groove, an H-shaped blind groove, a W-shaped blind groove, an M-shaped blind groove or a trapezoidal blind groove. In the first embodiment, the blind groove 30 is an arcuate blind groove 30. Of course, the specific shape of the blind groove 30 of the present invention is not limited, for example, the blind groove 30 may be a stepped structure with different sizes and shapes from top to bottom.

[0028] Preferably, the upper surface, the lower surface and / or each side surface of the blind slot 30 are provided with an unplated area 50 in a shape such as a bow shape, a W shape, an H shape, an M shape, a trapezoidal shape, etc., thereby realizing the capacitive negative coupling between the two first resonators 10 and the second resonator 20. More preferably, the blind slot 30 can be placed together with the frequency blind holes 30 corresponding to the first resonator 10 and the second resonator 20.

[0029] Preferably, a metal plating layer is provided on the surface of the dielectric waveguide filter 100. The dielectric material of the dielectric waveguide filter 100 is ceramic, and other conductive materials may also be used.

[0030] The coupling amount of the dielectric waveguide filter 100 may be determined by the size of the blind slot 30. The larger the area of ​​the blind slot 30, the larger the coupling amount of the dielectric waveguide filter 100. Therefore, the dielectric waveguide filter 100 of the present invention can adjust and realize different capacitive coupling amounts by adjusting the area size of the blind slot 30. For example, when the coupling amount required by the dielectric waveguide filter 100 is small, the area of ​​the blind slot 30 may be set to be small. When the coupling amount required by the dielectric waveguide filter 100 is large, the area of ​​the blind slot 30 may be set to be large.

[0031] Preferably, at least one unplated area 50 of regular or irregular shape is provided on the upper surface, lower surface and / or each side surface of the blind groove 30, thereby realizing capacitive negative coupling between the adjacent first resonator 10 and the second resonator 20. The unplated area 50 can be set to any shape such as circular, elliptical, square, diamond or trapezoidal. In the first embodiment, the unplated area 50 is circular, that is, a circle of unplated isolation ring 50 is set at the bottom of the blind groove 30, thereby introducing the TE102 mode, which is opposite to the TE101 mode of the front and rear cavities, and realizing capacitive negative coupling between the first resonator 10 and the second resonator 20.

[0032] More preferably, the coupling amount of the dielectric waveguide filter 100 may be determined by the size of the unplated region 50. The larger the area of ​​the unplated region 50 is, the greater the coupling amount of the dielectric waveguide filter 100 is; and / or, the coupling amount of the dielectric waveguide filter 100 may be determined by the number of the unplated regions 50. The greater the number of the unplated regions 50 is, the greater the coupling amount of the dielectric waveguide filter 100 is.

[0033] Therefore, the dielectric waveguide filter 100 of the present invention can adjust and realize different capacitive coupling amounts by adjusting the size and / or number of the unplated area 50. For example, when the coupling amount required by the dielectric waveguide filter 100 is small, only the upper surface or the lower surface of the blind slot 30 can be provided with the unplated area 50. When the coupling amount required by the dielectric waveguide filter 100 is large, the upper surface, the lower surface and each side surface of the blind slot 30 can be provided with the unplated area 50.

[0034] Preferably, a metal plating layer is provided on the surface of the dielectric waveguide filter 100. The dielectric material of the dielectric waveguide filter 100 can be an electrically conductive material such as ceramic.

[0035] It is worth reminding that Figure 1 The dielectric waveguide filter 100 is composed of six resonators. However, the dielectric waveguide filter 100 that can achieve capacitive negative coupling is not limited to the dielectric waveguide filter of six resonators, and the dielectric waveguide filter composed of more than or equal to three resonators can achieve this function. For example, the dielectric waveguide filter 100 can be a dielectric waveguide filter composed of three, four, five, seven, eight, nine, ten or more resonators. Select two resonators with cross-coupling poles, and add a blind slot greater than or equal to half the wavelength of the dielectric waveguide filter 100 between the two resonators, so that the coupling characteristics between the two resonators can be reversed, thereby achieving capacitive negative coupling.

[0036] Figure 2 The schematic diagram of the model structure of introducing an H-type blind slot between two resonators of the dielectric waveguide filter in the second embodiment of the present invention to realize capacitive negative coupling. The dielectric waveguide filter 100 in the second embodiment includes six resonators, each of which may include a resonant cavity, a resonant column, and a frequency blind hole. In addition, the present invention selects to set at least one H-type blind slot 30 with a length greater than or equal to half the wavelength of the dielectric waveguide filter 100 between the first resonator 10 and the second resonator 20 at the cross-coupling pole in the same cavity, that is, the overall length of the H-type blind slot 30 is greater than or equal to half the wavelength of the working frequency of the dielectric waveguide filter 100, so that the coupling characteristics between the first resonator 10 and the second resonator 20 can be reversed, thereby realizing capacitive negative coupling. Preferably, the H-type blind slot 30 is arranged on the side of the coupling window 40 between the first resonator 10 and the second resonator 20. The blind slot 30 of the dielectric waveguide filter 100 in the second embodiment is an H-type blind slot 30, and the other parts of the structure of the dielectric waveguide filter 100 are basically the same as those in the first embodiment, so they are not repeated.

[0037] Figure 3The schematic diagram of the model structure of introducing an M-type blind slot between two resonators of the dielectric waveguide filter in the third embodiment of the present invention to realize capacitive negative coupling. The dielectric waveguide filter 100 in the third embodiment includes six resonators, each of which can include a resonant cavity, a resonant column, and a frequency blind hole. In addition, the present invention selects to set at least one M-type blind slot 30 with a length greater than or equal to half the wavelength of the dielectric waveguide filter 100 between the first resonator 10 and the second resonator 20 at the cross-coupling pole in the same cavity, that is, the overall length of the M-type blind slot 30 is greater than or equal to half the wavelength of the working frequency of the dielectric waveguide filter 100, so that the coupling characteristics between the first resonator 10 and the second resonator 20 can be reversed, thereby realizing capacitive negative coupling. Preferably, the M-type blind slot 30 is arranged on the side of the coupling window 40 between the first resonator 10 and the second resonator 20. The blind slot 30 of the dielectric waveguide filter 100 in the second embodiment is an M-type blind slot 30, and the other parts of the structure of the dielectric waveguide filter 100 are basically the same as those in the first embodiment, so they are not repeated.

[0038] Figure 4 The schematic diagram of the model structure of introducing a W-shaped blind slot between two resonators of the dielectric waveguide filter in the fourth embodiment of the present invention to realize capacitive negative coupling. The dielectric waveguide filter 100 in the third embodiment includes six resonators, each of which may include a resonant cavity, a resonant column, and a frequency blind hole. In addition, the present invention selects to set at least one W-shaped blind slot 30 with a length greater than or equal to half the wavelength of the dielectric waveguide filter 100 between the first resonator 10 and the second resonator 20 at the cross-coupling pole in the same cavity, that is, the overall length of the W-shaped blind slot 30 is greater than or equal to half the wavelength of the working frequency of the dielectric waveguide filter 100, so that the coupling characteristics between the first resonator 10 and the second resonator 20 can be reversed, thereby realizing capacitive negative coupling. Preferably, the W-shaped blind slot 30 is arranged on the side of the coupling window 40 between the first resonator 10 and the second resonator 20. The blind slot 30 of the dielectric waveguide filter 100 in the second embodiment is a W-shaped blind slot 30, and the other parts of the structure of the dielectric waveguide filter 100 are basically the same as those in the first embodiment, so they are not repeated.

[0039] It is worth pointing out that although the structure of the dielectric waveguide filter 100 that can realize capacitive negative coupling of the present invention is based on Figure 1 to Figure 4 However, it is only a partial example of the implementation method of the present invention and is not intended to limit the present invention.

[0040] In summary, the present invention proposes a structural form for introducing capacitive negative coupling in a dielectric waveguide filter, wherein the dielectric waveguide filter includes at least three resonators, and a blind slot having a length greater than or equal to half the wavelength of the dielectric waveguide filter is arranged between two resonators at the cross-coupling poles in the same cavity, and the blind slot is preferably of a regular shape or an irregular shape and is arranged on the side of the coupling window between the two resonators, so that the coupling characteristics between the two resonators can be reversed, thereby realizing capacitive negative coupling. Preferably, the upper surface, the lower surface and / or each side surface of the blind slot are provided with an unplated area of ​​a regular shape or an irregular shape such as a bow shape, a W shape, an H shape, an M shape, etc., thereby realizing capacitive negative coupling between the two resonators. In this way, the dielectric waveguide filter of the present invention can realize capacitive negative coupling only through a conventional inductive coupling window structure, can improve the frequency selection characteristics and out-of-band suppression characteristics of the dielectric waveguide filter, and has the characteristics of simple implementation and convenient debugging. The present invention plays an important role in promoting the development of dielectric waveguide filters in modern miniaturized integrated communication systems.

[0041] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art may make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A dielectric waveguide filter capable of realizing capacitive negative coupling, characterized in that: The dielectric waveguide filter is composed of a dielectric block, which includes at least three resonators, and at least one blind slot with a length greater than or equal to half the wavelength of the dielectric waveguide filter is arranged between a first resonator and a second resonator at a cross-coupling pole in the same cavity, so that the coupling characteristics between the first resonator and the second resonator are reversed to generate capacitive negative coupling; The upper surface, the lower surface and / or each side surface of the blind groove are provided with at least one unplated area of ​​regular or irregular shape; The overall length of the blind slot is greater than or equal to a half wavelength of an operating frequency of the dielectric waveguide filter.

2. The dielectric waveguide filter according to claim 1, characterized in that The blind groove is of a regular shape or an irregular shape, and the blind groove is arranged on a side of a coupling window between the first resonator and the second resonator.

3. The dielectric waveguide filter according to claim 1, wherein: The blind groove is an arcuate blind groove, an H-shaped blind groove, a W-shaped blind groove, an M-shaped blind groove or a trapezoidal blind groove.

4. The dielectric waveguide filter according to claim 1, wherein: The blind slot and the frequency blind holes corresponding to the first resonator and the second resonator are placed together.

5. The dielectric waveguide filter according to claim 1, wherein: The magnitude of the coupling amount of the dielectric waveguide filter is determined by the size of the blind slot; the larger the area of ​​the blind slot is, the greater the coupling amount is.

6. The dielectric waveguide filter according to claim 1, wherein: The surface of the dielectric waveguide filter is covered with a metal plating layer.

7. The dielectric waveguide filter according to claim 1, wherein: The unplated area is circular, oval, square, diamond or trapezoidal.

8. The dielectric waveguide filter according to claim 1, wherein: The magnitude of the coupling amount of the dielectric waveguide filter is determined by the size of the unplated area. The larger the area of ​​the unplated area is, the greater the coupling amount is; and / or The magnitude of the coupling amount of the dielectric waveguide filter is determined by the number of the unplated areas. The greater the number of the unplated areas, the greater the coupling amount.

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