CN117712647A - Tunable filter - Google Patents

Abstract

The application provides a tunable filter, which relates to the technical field of communication; the tunable filter comprises a resonant cavity and a metal resonant column, wherein two ends of the metal resonant column are communicated, a first end of the metal resonant column is positioned in the resonant cavity, and the first end of the metal resonant column is covered with an elastic skin, so that a semi-closed elastic space which is opened at a second end of the metal resonant column is formed in the metal resonant column; the second end of the metal resonant column is connected with the first side edge of the resonant cavity, so that the tuning rod enters from the second end of the metal resonant column to enable the elastic skin to deform, and the resonant cavity is tuned. Therefore, through the structure, the metal resonant column forms a semi-closed elastic space, even if metal scraps are generated due to friction in the tuning process, the metal scraps can not enter the resonant cavity, the surface of the skin is smoother than that of the tuning rod, the power capacity is further improved, and poor intermodulation is reduced.

Description

Tunable filter

Technical Field

Embodiments of the present application relate to, but are not limited to, the field of communications technologies, and in particular, to a tunable filter.

Background

In the field of wireless communications, the tunable filter may be used as a base station radio frequency filter. In the debugging process of a traditional tunable filter, performance adjustment is often realized by adjusting the length of a tuning screw penetrating into the resonant cavity of the tunable filter. However, in this process, metal chips are generated between the tuning screw and the side (e.g., the cover plate) of the resonant cavity due to friction, and the chips fall into the cavity of the tunable filter, which causes high-power ignition and poor intermodulation, and affects the communication quality. Although a metal polish rod may be used, a small amount of threads remain at the end of the polish rod for fixing, so there is still a probability of intermodulation defect due to metal chips generated by friction during debugging, and thus there is a need for a tunable filter that can reduce the probability of intermodulation defect during debugging.

Disclosure of Invention

The following is a summary of the subject matter described in detail herein. This summary is not intended to limit the scope of the claims. The embodiment of the application provides a tunable filter, which can reduce the probability of poor intermodulation in the debugging process.

According to the tunable filter provided by the embodiment of the application, the tunable filter comprises a resonant cavity and a metal resonant column, wherein two ends of the metal resonant column are communicated, a first end of the metal resonant column is positioned in the resonant cavity, and the first end of the metal resonant column is covered with an elastic skin, so that a semi-closed elastic space which is opened at a second end of the metal resonant column is formed in the metal resonant column; the second end of the metal resonant column is connected with the first side edge of the resonant cavity, so that the tuning rod enters from the second end of the metal resonant column and causes the elastic skin to deform, and the resonant cavity is tuned.

Therefore, the above embodiments of the present application have at least the following advantages: through getting into the tuning rod from the second end of metal resonance post, along with the change of tuning rod in depth length this moment for the tuning rod produces pressure to the elastic skin, thereby makes elastic skin take place deformation, and then makes the electric capacity change, thereby realizes the tuning to resonant frequency. Meanwhile, as the metal resonant column forms a semi-closed elastic space, even if metal scraps are generated due to friction in the tuning process, the metal scraps can not enter the resonant cavity, and the surface of the skin is smoother than that of the tuning rod, so that the power capacity can be further improved, and the intermodulation defect is reduced. Therefore, the method and the device can reduce the probability of poor intermodulation in the debugging process and improve the power capacity.

According to some embodiments of the present application, the first side is provided with a mounting structure, the mounting structure has a first spacing fixed slot, the lateral wall of the first spacing fixed slot with first side is connected, just the first spacing fixed slot with resonant cavity lateral wall intercommunication, first spacing fixed slot with the second end of metal resonance post can be dismantled and is connected.

According to some embodiments of the present application, the mounting structure further has a second limit fixing groove, the directions of the notches of the first limit fixing groove and the second limit fixing groove are opposite, the first limit fixing groove and the second limit fixing groove share a bottom edge, and an opening of the second limit fixing groove is connected with the first side edge; the bottom edge is provided with a through hole communicated with the metal resonance column, so that the tuning rod penetrates into the semi-closed elastic space in the metal resonance column from the through hole.

According to some embodiments of the present application, the inner side wall of the first limit fixing groove is provided with a first internal thread, the inner hole of the second end of the metal resonance column is provided with a hexagonal hole, and the outer side wall of the second end of the metal resonance column is provided with a first external thread matched with the first internal thread.

According to some embodiments of the present application, the tunable filter further comprises a tuning rod, an outer sidewall of the tuning rod is provided with a second external thread, and an inner sidewall of the second end of the metal resonator column is provided with a second internal thread matching the second external thread.

According to some embodiments of the application, the first limit fixing groove is riveted and fixed with the second end of the metal resonant column.

According to some embodiments of the present application, the tunable filter further includes a cannulated screw, an inner hole of the cannulated screw is a hexagon socket, and the cannulated screw is used for riveting the first limiting fixing groove and the second end of the metal resonant column.

According to some embodiments of the application, the outer side wall of the first limiting fixing groove is provided with a third external thread, and the second end of the metal resonant column is provided with a third internal thread matched with the third external thread.

According to some embodiments of the present application, the resonant cavity includes a cavity body and a cover plate, the cavity body is a cavity body with a hollow cavity body and an opening at one side, the cover plate is covered at the opening of the cavity body, and the first side is the cover plate or the bottom of the cavity body.

According to some embodiments of the present application, the tunable filter further includes a tuning rod, and a middle portion of the tuning rod and an end near the metal resonant post are provided as smooth rods.

Drawings

The accompanying drawings are included to provide a further understanding of the technical aspects of the present application, and are incorporated in and constitute a part of this specification, illustrate the technical aspects of the present application and together with the examples of the present application, and not constitute a limitation of the technical aspects of the present application.

FIG. 1 is a schematic cross-sectional view of one embodiment of a tunable filter provided herein;

FIG. 2 is a schematic cross-sectional view of another embodiment of a tunable filter provided herein;

FIG. 3 is a schematic cross-sectional view of another embodiment of a tunable filter provided herein;

FIG. 4 is a schematic cross-sectional view of another embodiment of a tunable filter provided herein;

fig. 5 is a schematic cross-sectional structure of another embodiment of a tunable filter provided herein.

Reference numerals:

resonant cavity 100, first side 110, mounting structure 120, first spacing fixed slot 121, second spacing fixed slot 122, first external thread 131, second external thread 132, hollow screw 133, third external thread 134, cavity body 140, cover plate 150, metal resonant column 200, elastic skin 210, and,

Tuning rod 300.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application will be further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the present application.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing embodiments of the present application only and is not intended to be limiting of the present application. The terms "first," "second," "third," "fourth," and the like in the description of the present application and in the above-described figures, if any, are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order.

Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of embodiments of the disclosure. One skilled in the relevant art will recognize, however, that the disclosed aspects may be practiced without one or more of the specific details, or with other methods, components, devices, steps, etc. In other instances, well-known methods, devices, implementations, or operations are not shown or described in detail to avoid obscuring aspects of the disclosure.

In the field of wireless communications, the tunable filter may be used as a base station radio frequency filter. In the debugging process of a traditional tunable filter, performance adjustment is often realized by adjusting the length of a tuning screw penetrating into the resonant cavity of the tunable filter. However, in this process, metal chips are generated between the tuning screw and the side (e.g., the cover plate) of the resonant cavity due to friction, and the chips fall into the cavity of the tunable filter, which causes high-power ignition and poor intermodulation, and affects the communication quality. Although a metal polish rod may be used, a small amount of threads remain at the end of the polish rod for fixing, so there is still a probability of intermodulation defect due to metal chips generated by friction during debugging, and thus there is a need for a tunable filter that can reduce the probability of intermodulation defect during debugging. Based on this, the embodiment of the application provides a tunable filter, which can reduce the probability of intermodulation defect in the debugging process.

Referring to fig. 1 to 5, a tunable filter according to an embodiment of the present application includes a resonant cavity 100 and a metal resonant cylinder 200, two ends of the metal resonant cylinder 200 are penetrated, a first end of the metal resonant cylinder 200 is located in the resonant cavity 100 and the first end of the metal resonant cylinder 200 is covered with an elastic skin 210, so that a semi-closed elastic space opened at a second end of the metal resonant cylinder 200 is formed in the metal resonant cylinder 200; the second end of the metal resonator column 200 is connected to the first side 110 of the resonator body 100 such that the tuning rod 300 enters from the second end of the metal resonator column 200 and causes the elastic skin 210 to deform to tune the resonator body 100.

Therefore, the above embodiments of the present application have at least the following advantages: by entering the tuning rod 300 from the second end of the metal resonant column 200, the tuning rod 300 generates pressure on the elastic skin 210 along with the change of the deep length of the tuning rod 300, so that the elastic skin 210 is deformed, and the capacitance is changed, thereby realizing tuning of the resonant frequency. Meanwhile, since the metal resonating posts 200 form a semi-closed elastic space, even if metal scraps are generated due to friction during tuning, the metal scraps do not enter the inside of the resonating cavity 100, and the surface of the skin is smoother than the tuning rod 300, so that the power capacity can be further improved, and intermodulation defects can be reduced. Therefore, the method and the device can reduce the probability of poor intermodulation in the debugging process and improve the power capacity.

It should be appreciated that the elastic skin 210 has elasticity, so that when the tuning rod 300 applies pressure to the elastic skin 210, the elastic skin 210 deforms, thereby achieving tuning.

It should be appreciated that the elastic skin 210 may be made of plastic metal, such as aluminum, silver, etc., and may be selectively provided by those skilled in the art according to actual needs.

It should be appreciated that the semi-closed elastic space is realized by using the metal resonant tank 200, and the manufacturing is simpler. The metal resonant column 200 may be mounted on the cover plate 150 of the resonant cavity 100, or may be mounted on the cavity body of the resonant cavity 100, and at this time, due to the arrangement of the resonant cavity 100, the processing of the cover plate 150 and the cavity body may be simpler, and only a space for mounting the metal resonant column 200 is required. The placement of the metal resonator column 200 can be selected by those skilled in the art according to actual requirements. When the metal resonant tank 200 is disposed on the cover plate 150, the first side 110 is the cover plate 150, and when tuning, the space between the cover plate 150 and the elastic skin 210 is adjusted, so that the power capacity can be further improved and the intermodulation can be reduced. When the metal resonant tank 200 is disposed in the cavity body 140, the first side 110 represents the bottom of the cavity body 140, and by adjusting the distance between the elastic skin 210 and the main cavity, the power capacity is further improved and intermodulation defects are reduced.

It should be appreciated that the first end of the metallic resonating post 200 may extend outwardly as shown in fig. 1-5 to provide sufficient mounting space for electrical connection with the elastic skin 210. The edges of the first end portions of the elastic skin 210 and the metal resonant columns 200 may be electrically connected by laser welding, soldering or press riveting, and may be selectively set by a person skilled in the art according to actual needs, which will not be described in detail.

It should be understood that the number of metal resonator columns 200 is not limited in the embodiments of the present application, and may be selectively set according to the resonator cavities formed in the resonator body 100.

As can be appreciated, as shown in fig. 1 to 5, the first side 110 is provided with a mounting structure 120, the mounting structure 120 has a first limiting fixing groove 121, a side wall of the first limiting fixing groove 121 is connected with the first side 110, the first limiting fixing groove 121 is communicated with an outer side wall of the resonant cavity 100, and the first limiting fixing groove 121 is detachably connected with the second end of the metal resonant column 200.

It should be understood that the side wall of the first limiting fixing groove 121 may be directly connected to the first side edge 110, or may be indirectly connected to the first side edge (as shown in fig. 1 to 3), for which, a person skilled in the art may selectively set the mounting structure 120 according to actual needs.

It should be appreciated that the convenience of mounting the metal resonator column 200 can be improved by providing the first limit fixing groove 121.

It should be noted that the mounting structure 120 may be integrally formed with the first side 110, as shown in fig. 1, 2, 4 and 5, and the mounting structure 120 and the chamber body 140 are integrally formed, and in other embodiments, as shown in fig. 3, the mounting structure 120 is a relatively independent structure from the cover plate 150.

As can be appreciated, referring to fig. 1 to 5, the mounting structure 120 further has a second limiting and fixing groove 122, the directions of the notches of the first limiting and fixing groove 121 and the second limiting and fixing groove 122 are opposite, the first limiting and fixing groove 121 and the second limiting and fixing groove 122 share a bottom edge, and the opening of the second limiting and fixing groove 122 is connected with the first side edge 110; the bottom side is provided with a through hole communicating with the metal resonating column 200 such that the tuning rod 300 penetrates into the semi-closed elastic space inside the metal resonating column 200 from the through hole.

It should be understood that the manner in which the first limit fixing groove 121 and the second limit fixing groove 122 are formed is not limited in this application, and may be selectively set by those skilled in the art according to actual needs.

It should be appreciated that by providing the second limiting fixing groove 122, the outer surface of the first side 110 forms a counter bore, at this time, the tuning rod 300 may be fixed in the counter bore after tuning, so as to reduce the probability of damage to the exposed surface of the tuning rod 300.

It can be understood that, referring to fig. 1, the inner sidewall of the first limit fixing groove 121 is provided with a first internal thread, the inner hole of the second end of the metal resonance post 200 is provided with a hexagonal hole, and the outer sidewall of the second end of the metal resonance post 200 is provided with a first external thread 131 matched with the first internal thread.

It should be understood that, through the threaded connection of the first external thread 131 and the first internal thread, the convenience of installation of the metal resonance column 200 can be improved, and meanwhile, the inner hole of the metal resonance column 200 is set to be an inner hexagonal hole, so that the convenience of installation can be further improved by using the inner hexagonal wrench to install the covered metal resonance column 200 from the bottom of the cavity.

It should be understood that after the metal resonant cylinder 200 is screwed to the first limiting fixing groove 121, the metal resonant cylinder may be further fixed by welding, etc., which is not limited in this embodiment, and may be selectively set by those skilled in the art according to actual needs.

As can be appreciated, referring to fig. 1, the tunable filter further includes a tuning rod 300, an outer sidewall of the tuning rod 300 is provided with a second external thread 132, and an inner sidewall of the second end of the metal resonator column 200 is provided with a second internal thread matching the second external thread 132.

By providing the second external thread 132 and the second internal thread, the tuning rod 300 can be fixed.

It can be appreciated that referring to fig. 4, the first limit fixing groove 121 is riveted and fixed with the second end of the metal resonator column 200.

As can be appreciated, referring to fig. 4, the tunable filter further includes a cannulated screw 133, wherein an inner hole of the cannulated screw 133 is a hexagonal through hole, and the cannulated screw 133 is used to rivet the first limiting fixing groove 121 with the second end of the metal resonator column 200.

It will be appreciated that referring to fig. 5, the outer sidewall of the first limit fixing groove 121 is provided with a third external thread 134, and the second end of the metal resonant cylinder 200 is provided with a third internal thread matching the third external thread 134.

It should be understood that the fixing manner of the first limiting fixing groove 121 and the second end of the metal resonant column 200 is not limited in this application, a person skilled in the art may select a threaded connection, a rivet connection, etc., and the position of the threaded arrangement may be selectively set by a person skilled in the art according to actual needs, which is not too much restricted in this embodiment of the present application.

It should be understood that the specific material of the tuning rod 300 is not limited in the embodiments of the present application, and in some embodiments the tuning rod 300 is metal or plastic or glass or ceramic.

As can be appreciated, referring to fig. 1 to 5, the resonant cavity 100 includes a cavity body 140 and a cover plate 150, the cavity body 140 is a hollow cavity with one side open, the cover plate 150 is disposed at the opening of the cavity body 140, and the first side 110 is the cover plate 150 or the bottom of the cavity body 140.

It should be appreciated that by dividing the resonant cavity 100 into the cavity body 140 and the cover plate 150 which are detachably connected, the convenience of tuning can be improved.

It will be appreciated that referring to fig. 2, the tunable filter further includes a tuning rod 300, and a middle portion of the tuning rod 300 and one end near the metal resonator post 200 are provided as smooth rods.

Illustratively, in the schematic structural diagram of the metal resonator shown in fig. 1, the upper surface of the metal resonator column 200 is covered with a metal skin (i.e., an elastic skin 210), and the metal skin forms an electrical connection at the edge of the metal resonator column 200 by means of laser welding, soldering, or press-riveting, etc., and the electrical connection forms a closed space between the metal resonator column 200 and the metal skin, and the entire metal resonator column 200 forms a semi-closed elastic space, so as to prevent the debugged metal scraps from entering the cavity.

It should be understood that in the embodiment of the present application, the metal resonator column 200 is connected to the metal cavity by means of threads or welding, riveting, or the like. As shown in fig. 1, the inner hole at the bottom of the metal resonant column 200 is an inner hexagonal hole, and the outer diameter is tapped with the first external thread 131, so as to facilitate the use of an inner hexagonal wrench to install the covered metal resonant column 200 from the bottom of the cavity. The debug bar bottom outer diameter has a second external thread 132 that forms a threaded connection with the chamber body 140 at the bottom internal bore (i.e. through hole). The material of the test rod can be, but is not limited to, metal, plastic, glass, and ceramic. The tuning rod deforms the elastic skin 210 by pressing the elastic skin 210 so as to tune the resonance frequency.

For example, as shown in fig. 2, the tuning rod may be made into a polished rod 10, and the polished rod strikes the skin to plastically deform the elastic skin 210, thereby achieving the purpose of frequency tuning.

Illustratively, as shown in fig. 3, the tunable filter includes a cavity body 140, a metal resonator post 200, a tuning rod, a metal skin (i.e., an elastic skin 210), a cover plate 150, and a mounting structure 120. The mounting structure 120 is used to connect the cover plate 150 to the skin metal resonator.

Illustratively, as shown in fig. 4, the connection between the metal resonator column 200 and the chamber body 140 is crimped with a cannulated screw 133, and the internal bore of the cannulated screw 133 is a hexagonal through hole to facilitate installation from the bottom of the chamber.

It should be appreciated that embodiments of the present application may employ any of the methods shown in fig. 1-4 for the placement of tunable metal resonators.

In summary, the tunable filter of the embodiment of the present application may debug that generated metal chips are isolated outside the cavity, so as to reduce high-power ignition and intermodulation defects caused by the chips falling into the cavity.

In addition, the skin increases the capacitance between the metal resonant column 200 and the cover plate 150 (fig. 1 scheme) or the cavity (fig. 3 scheme), and at the same resonant frequency, the distance between the metal resonant column 200 of the skin and the cover plate 150 (fig. 1 scheme) is larger, or the distance between the metal resonant column 200 of the skin and the cavity is larger (fig. 3 scheme); therefore, the power capacity can be further improved and intermodulation defects can be reduced.

While the preferred embodiments of the present application have been described in detail, the present application is not limited to the above embodiments, and various equivalent modifications and substitutions can be made by those skilled in the art without departing from the spirit of the present application, and these equivalent modifications and substitutions are intended to be included in the scope of the present application as defined in the appended claims.

Claims (10)

1. A tunable filter, comprising:

a resonant cavity;

the two ends of the metal resonance column are communicated, the first end of the metal resonance column is positioned in the resonance cavity, and the first end of the metal resonance column is covered with an elastic skin, so that a semi-closed elastic space which is opened at the second end of the metal resonance column is formed in the metal resonance column; the second end of the metal resonant column is connected with the first side edge of the resonant cavity, so that the tuning rod enters from the second end of the metal resonant column and causes the elastic skin to deform, and the resonant cavity is tuned.

2. The tunable filter of claim 1, wherein the first side is provided with a mounting structure having a first spacing fixed slot, a side wall of the first spacing fixed slot is connected to the first side, and the first spacing fixed slot is in communication with an outer side wall of the resonant cavity, and the first spacing fixed slot is detachably connected to the second end of the metal resonant column.

3. The tunable filter of claim 2, wherein the mounting structure further has a second limiting and fixing groove, the first limiting and fixing groove and the second limiting and fixing groove are opposite in notch direction, the first limiting and fixing groove and the second limiting and fixing groove share a bottom edge, and an opening of the second limiting and fixing groove is connected with the first side edge; the bottom edge is provided with a through hole communicated with the metal resonance column, so that the tuning rod penetrates into the semi-closed elastic space in the metal resonance column from the through hole.

4. A tunable filter according to claim 2 or 3, wherein the inner side wall of the first limit fix groove is provided with a first internal thread, the inner hole of the second end of the metal resonator column is provided with an internal hexagonal hole, and the outer side wall of the second end of the metal resonator column is provided with a first external thread matching the first internal thread.

5. The tunable filter of claim 4, further comprising a tuning rod, an outer sidewall of the tuning rod being provided with a second external thread, an inner sidewall of the second end of the metal resonator post being provided with a second internal thread that mates with the second external thread.

6. A tunable filter according to claim 2 or 3, wherein the first limit fix groove is riveted to the second end of the metal resonator post.

7. The tunable filter of claim 6, further comprising a cannulated screw having an internal bore of a hexagonal through bore, the cannulated screw configured to rivet the first limit fixation slot with the second end of the metal resonating post.

8. A tunable filter according to claim 2 or 3, wherein the outer side wall of the first limit fix groove is provided with a third external thread, and the second end of the metal resonator column is provided with a third internal thread matching the third external thread.

9. The tunable filter of claim 1, wherein the resonant cavity comprises a cavity body and a cover plate, the cavity body is a hollow cavity with one side open, the cover plate covers the opening of the cavity body, and the first side is the bottom of the cover plate or the cavity body.

10. The tunable filter of claim 1, further comprising a tuning rod, a middle portion of the tuning rod and an end near the metal resonator post being provided as a smooth rod body.