CN219286628U

CN219286628U - Metal filter

Info

Publication number: CN219286628U
Application number: CN202320669985.1U
Authority: CN
Inventors: 周亮; 张勇
Original assignee: Suzhou Xiecheng Microwave Technology Co ltd
Current assignee: Suzhou Xiecheng Microwave Technology Co ltd
Priority date: 2023-03-30
Filing date: 2023-03-30
Publication date: 2023-06-30
Anticipated expiration: 2033-03-30

Abstract

The utility model relates to a metal filter, wherein a convex ring is arranged on the lower surface of a cover plate of the metal filter, and extends downwards longitudinally along the vertical direction of the cover plate and stretches into the inner cavity of a corresponding filter cavity; the convex ring is of a circular three-dimensional structure; the convex ring keeps a certain horizontal distance with the upper end of the resonator of the filter, and the central axis of the resonator is coincident with the central axis of the convex ring; the number of the convex rings is one or more. The metal filter in the utility model has better out-of-band rejection performance of high frequency band without additionally adding a low-pass filter, has simple structural design, avoids excessive reduction of design space of the metal filter, reduces product cost, and can be widely used in the field of communication.

Description

Metal filter

Technical Field

The utility model relates to the field of filters, in particular to a metal filter.

Background

In a communication system, a filter is a common and important component, and can effectively filter clutter signals, so that the communication quality and the communication stability are greatly improved. The frequency band of the conventional metal coaxial filter is usually within 5GHz, but due to the characteristics of radio frequency signals, multiple resonances can be generated, and the generated resonance frequency band is within a KU band (more than 10 GHz), so that serious interference is generated to satellite communication and military communication, and communication equipment manufacturers have higher demands on the suppression of the high frequency band of the filter.

In order to ensure that the out-of-band rejection of a high-frequency band can meet the requirement, the traditional metal filter needs to be additionally provided with a low-pass filter on a filter component to improve the out-of-band rejection of the high-end, so that the space for designing and applying the filter is reduced, the structural design is complex, and the product cost is increased.

Disclosure of Invention

In order to solve the problems in the prior art, the utility model provides the metal filter which can meet the out-of-band rejection performance of a high frequency band without additionally adding a low-pass filter, and has the advantages of simple structural design and low product cost.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

a metal filter, comprising:

the filter cavity is provided with a hollow inner cavity, and the upper end face of the filter cavity is of an opening structure;

a resonator disposed in an inner cavity of the filter cavity and having a resonant cavity;

the tuning screw rod is arranged opposite to the resonant cavity of the resonator up and down;

the filter comprises a filter cavity, a cover plate, a tuning screw, a filter and a filter, wherein the filter cavity is provided with a plurality of resonant cavities, the resonant cavities are provided with a plurality of resonant cavities, the filter cavity is provided with a plurality of resonant cavities, the resonant cavities are provided with resonant cavities, and the resonant cavities are provided with resonant cavities;

the method is characterized in that: the lower surface of the cover plate is provided with a convex ring which extends downwards to form a ring-shaped three-dimensional structure, the convex rings are in one-to-one correspondence with the resonators, and the central axis of the resonators is coincident with the central axis of the convex ring;

the inner diameter of the convex ring is larger than the outer diameter of the resonator.

Preferably, the height and width of the convex ring are adjusted according to the designed frequency band.

Further, in the horizontal direction of the cover plate, the lower end surface of the convex ring is higher or lower than the upper surface of the upper end of the resonator.

Further, in the horizontal direction of the cover plate, the lower end face of the convex ring is flush with the lower surface of the upper end of the resonator, the upper end of the resonator is surrounded, and the height of the convex ring is 1.5-3mm.

Further, the widths of the upper end and the lower end of the convex ring are equal, and the width is 0.2-0.4mm.

Further, the width of the collar is less than the width of the tuning screw.

Further, the number of the convex rings is one or more.

Preferably, the horizontal distance between the collar and the resonator is adjusted according to the product power capacity requirements.

Further, the horizontal distance between the convex ring and the upper end of the resonator is 0.2-0.5mm.

Further, a horizontal distance between the collar and an upper end of the resonator is less than or equal to a horizontal distance between the collar and an inner cavity wall of the filter cavity.

Further, the convex ring and the cover plate are integrally formed.

Further, the convex ring is made of metal.

The relevant content explanation in the technical scheme is as follows:

in the above scheme, the upper and lower are defined by the distance between the upper end and the lower end relative to the open end of the filter cavity, the upper end and the upper end face are one end close to the open end of the filter cavity and the end face thereof, and the lower end face are one end far away from the open end of the filter cavity and the end face thereof.

Due to the application of the technical scheme, compared with the prior art, the utility model has the following advantages:

the convex ring and the height and width of the convex ring are adjusted, so that the frequencies of the second harmonic and the third harmonic can be pushed back, and the convex ring has better out-of-band rejection performance of a high frequency band under the condition that a low-pass filter is not required to be additionally arranged. In addition, the metal filter has simple structural design, avoids excessive reduction of design space of the metal filter, reduces product cost, and can be widely applied to the field of communication.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the description of the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a cut-away view of a cavity of a metal filter provided in an exemplary embodiment of the present disclosure;

FIG. 2 is a single-cavity simulation diagram of a metal filter provided by an exemplary embodiment of the present disclosure;

FIG. 3 is a single-cavity simulation diagram of a conventional structural filter;

FIG. 4 is a single-cavity simulation result of a metal filter provided by an exemplary embodiment of the present disclosure;

single-cavity simulation results for a filter of the conventional structure of fig. 5.

Wherein, the reference numerals include: 1-a filter cavity; a 2-resonator; 3-tuning a screw; 4-cover plate; 5-convex ring.

Detailed Description

The utility model will be further described with reference to examples of embodiments shown in the drawings.

The present utility model provides a metal filter, as shown in fig. 1, the metal filter includes:

the filter cavity 1 is provided with a hollow inner cavity, and the upper end face of the filter cavity is of an opening structure.

And a resonator 2 disposed in the inner cavity of the filter cavity 1 and having a resonant cavity, the bottom of the resonator 2 being fixed to the upper surface of the bottom wall of the filter cavity 1 in one or more numbers.

And a tuning screw 3 disposed opposite to the resonator cavity of the resonator 2 up and down.

The cover plate 4 is detachably arranged on the upper end surface of the filter cavity 1, and is provided with through holes corresponding to the resonant cavities of the resonators 2 one by one, and the specific corresponding mode is that when the cover plate 4 is covered on the upper end surface of the filter cavity 1, the cover plate is arranged opposite to the resonant cavities of the resonators 2 up and down.

The inner wall of the through hole is provided with an internal thread, the diameter of the through hole is matched with that of the tuning screw 3, the tuning screw 3 is rotatably fixed in the cover plate 4 through the through hole, the height of the tuning screw 3 in the resonant cavity of the resonator 2 is adjustable, the frequency obtaining range is wide, and specifically, when the tuning screw 3 rotates downwards, the frequency obtained by tuning is lower, and is reversely higher.

The lower surface of apron 4 is provided with bulge loop 5, and the material of bulge loop 5 is the metal, and bulge loop 5 extends vertically downwardly along the vertical direction of apron 4, stretches into the inner chamber of corresponding filter cavity 1, can change the electric capacity in the filter cavity 1, and then changes the resonant frequency of circuit, realizes the adjustment to the frequency range of filter.

The bulge loop 5 is the three-dimensional structure of ring, and bulge loop 5 and resonator 2 one-to-one, and bulge loop 5 and the upper end of resonator 2 keep certain horizontal distance, and the central axis of resonator 2 coincides with the central axis of bulge loop 5, and the internal diameter of bulge loop 5 is greater than the diameter of the upper end of resonator 2 for bulge loop 5 can encircle setting up in the periphery of resonator 2, also can be located directly over the resonator 2, produces the influence of different degree to the resonant frequency of resonator 2.

The number of the convex rings 5 is one or more, and the specific number depends on the number of the resonators 2. Specifically, the number of the convex rings 5 is equal to the number of the resonators 2, and is 2.

The convex ring 5 and the cover plate 4 are integrally formed, so that the installation of various parts in the cavity in the prior art is avoided, and the stability of filtering operation is further improved.

The height and width of the convex ring 5 can directly influence the filtering effect of the filter on the high frequency band, so that the height and width of the convex ring 5 can be adjusted according to the designed frequency band.

Further, in the horizontal direction of the cover plate 4, the lower end face of the collar 5 is higher or lower than the upper surface of the upper end of the resonator 2, and the height H1 of the collar 5 is 1.5-3mm, so that the collar 5 surrounds the upper end of the resonator 2 or is located directly above the resonator 2. When the lower end surface of the convex ring 5 is level with the lower surface of the upper end of the resonator 2, the convex ring 5 surrounds the upper end of the resonator 2, and the height of the convex ring 5 is 2-3mm, which is equivalent to adjusting the height of the resonator 2, so that the frequency modulation range of the filter is changed.

Further, the upper end and the lower end of the convex ring 5 have the same width, and become a hollow cylinder, and the width W1 is 0.2-0.4mm. In addition, the width of the convex ring 5 is smaller than the width of the tuning screw 3, so that after the width and the height of the convex ring 5 are fixed, the frequency of the second harmonic wave and the third harmonic wave can be pushed back by adjusting the tuning screw 3, and the convex ring has better out-of-band rejection performance of a high frequency band under the condition that a low-pass filter is not required to be additionally added, the adoption of the low-pass filter is avoided, and the designable application space of the filter is enlarged.

The horizontal distance between the collar 5 and the resonator 2 is adjusted according to the product power capacity requirements, in general the larger the product power capacity the larger its size.

The horizontal distance W2 between the collar 5 and the upper end of the resonator 2 is 0.2-0.5mm and the horizontal distance between the collar 5 and the upper end of the resonator 2 is less than or equal to the horizontal distance between the collar 5 and the inner cavity wall of the filter cavity 1.

In another embodiment, the number of convex rings 5 is equal to the number of resonators 2, and is 1, and in this case, a single-cavity filter is shown in fig. 2. And (3) analyzing simulation results of the filter with the single cavity filter with the traditional structure. Compared with the metal filter in the present embodiment, the single-cavity filter of the conventional structure mainly lacks the cover plate 4 and the downward extending convex ring 5 with a ring-shaped three-dimensional structure arranged on the lower surface thereof, and the single-cavity simulation diagram is shown in fig. 3.

The simulation results are shown in fig. 4 and 5.

Through the comparative analysis of fig. 4 and fig. 5, the simulated single cavity has the same size, the simulated frequency is the same, the quality factor of the single cavity is the same, and compared with the traditional cavity design, the metal filter in the patent is adopted to enable the 2-order harmonic frequency to be pushed back by 700MHz, the 3-order harmonic frequency to be pushed back by 2.3GHz, and the metal filter has better out-of-band rejection performance of a high frequency band.

In another embodiment, the number of convex rings 5 and the number of resonators 2 may be 3, 4, etc.

The above embodiments are provided to illustrate the technical concept and features of the present utility model and are intended to enable those skilled in the art to understand the content of the present utility model and implement the same, and are not intended to limit the scope of the present utility model. All equivalent changes or modifications made in accordance with the spirit of the present utility model should be construed to be included in the scope of the present utility model.

Claims

1. A metal filter, comprising:

the filter cavity (1) is provided with a hollow inner cavity, and the upper end face of the filter cavity is of an opening structure;

a resonator (2) which is arranged in the inner cavity of the filter cavity (1) and is provided with a resonant cavity;

a tuning screw (3) which is arranged to be vertically opposite to the resonant cavity of the resonator (2);

the cover plate (4) is detachably arranged on the upper end face of the filter cavity (1) and is provided with through holes corresponding to the resonant cavities of the resonators (2) one by one, the inner walls of the through holes are provided with internal threads, and the tuning screw (3) is rotatably fixed in the cover plate (4) through the through holes;

the method is characterized in that: the lower surface of the cover plate (4) is provided with a convex ring (5) which extends downwards to form a ring-shaped three-dimensional structure, the convex rings are in one-to-one correspondence with the resonators (2), and the central axis of the resonators (2) is coincident with the central axis of the convex ring (5);

the inner diameter of the convex ring (5) is larger than the outer diameter of the resonator (2).

2. The metal filter of claim 1, wherein: in the horizontal direction of the cover plate (4), the lower end surface of the convex ring (5) is higher or lower than the upper surface of the upper end of the resonator (2).

3. The metal filter of claim 2, wherein: in the horizontal direction of the cover plate (4), the lower end face of the convex ring (5) is flush with the lower surface of the upper end of the resonator (2), the upper end of the resonator (2) is surrounded, and the height of the convex ring (5) is 1.5-3mm.

4. The metal filter of claim 1, wherein: the width of the upper end and the width of the lower end of the convex ring (5) are equal, and the width is 0.2-0.4mm.

5. The metal filter of claim 4, wherein: the width of the convex ring (5) is smaller than the width of the tuning screw (3).

6. The metal filter of claim 1, wherein: the number of the convex rings (5) is one or more.

7. A metal filter according to claim 1 or 6, characterized in that: the horizontal distance between the convex ring (5) and the upper end of the resonator (2) is 0.2-0.5mm.

8. The metal filter of claim 1, wherein: the horizontal distance between the convex ring (5) and the upper end of the resonator (2) is smaller than or equal to the horizontal distance between the convex ring (5) and the inner cavity wall of the filter cavity (1).

9. The metal filter of claim 1, wherein: the convex ring (5) and the cover plate (4) are integrally formed.

10. The metal filter of claim 1, wherein: the convex ring (5) is made of metal.