A waveguide bandpass filter based on a tunable pin assembly and a metal membrane

Abstract

The utility model discloses a waveguide band pass filter based on adjustable pin nail assembly and metal diaphragm belongs to filter technical field for solving the technical problem that only can adjust work frequency or coupling bandwidth of current waveguide band pass filter. The waveguide band pass filter of the utility model includes waveguide tube, adjustable pin nail assembly and metal diaphragm, and the waveguide tube contains at least two resonant cavities that communicate in turn, and the metal diaphragm is fixed at the connecting place between adjacent resonant cavities, and the adjustable pin nail assembly includes first adjustable pin nail assembly and second adjustable pin nail assembly, and the first adjustable pin nail assembly is used for adjusting the resonant frequency of resonant cavity, and the second adjustable pin nail assembly is used for adjusting the coupling degree between resonant cavities. The utility model improves the debuggability of waveguide band pass filter.

Description

Technical Field

[0001] This utility model belongs to the field of filter technology and relates to a waveguide bandpass filter based on an adjustable pin assembly and a metal diaphragm. Background Technology

[0002] Waveguide bandpass filters are core components of microwave and millimeter-wave systems. They have advantages such as large operating bandwidth, low in-band insertion loss, and large power capacity. They are widely used in high-frequency, low-loss, and high-power radio frequency systems, mainly to achieve frequency selection and noise suppression functions. Their performance directly affects the signal quality of communication, radar, satellite and other systems.

[0003] Because high-frequency systems are sensitive to structural tolerances, waveguide bandpass filters often exhibit problems such as operating frequency deviation and large in-band reflections after fabrication, rendering the devices unusable. In existing technologies, adjustable pins for frequency tuning can only adjust the operating frequency at a single point, failing to address bandwidth considerations; sliding metal diaphragms for bandwidth tuning can only adjust the coupling bandwidth, not the resonant frequency. Furthermore, the conductive grease on the diaphragm's sliding surface is prone to volatilization at high temperatures, causing performance drift and making it difficult to simultaneously solve the problems of frequency deviation and in-band reflections. Utility Model Content

[0004] Based on the above analysis, this utility model aims to provide a waveguide bandpass filter based on an adjustable pin assembly and a metal diaphragm, in order to solve the technical problem that existing waveguide bandpass filters can only adjust the operating frequency or coupling bandwidth.

[0005] The purpose of this utility model is mainly achieved through the following technical solutions.

[0006] This invention provides a waveguide bandpass filter based on an adjustable pin assembly and a metal diaphragm, comprising a waveguide, an adjustable pin assembly, and a metal diaphragm; the waveguide includes at least two resonant cavities connected in sequence, and the metal diaphragm is fixed at the connection between adjacent resonant cavities; the adjustable pin assembly includes a first adjustable pin assembly and a second adjustable pin assembly, the first adjustable pin assembly being used to adjust the resonant frequency of the resonant cavities, and the second adjustable pin assembly being used to adjust the coupling degree between the resonant cavities.

[0007] Furthermore, the adjustable pin assemblies are arranged sequentially at intervals along the length of the waveguide.

[0008] Furthermore, the position of the first adjustable pin assembly corresponds to the center of the resonant cavity.

[0009] Furthermore, the position of the second adjustable pin assembly corresponds to the position of the metal diaphragm.

[0010] Furthermore, the metal diaphragms are arranged in pairs, with the second adjustable pin assembly located between the two paired metal diaphragms.

[0011] Furthermore, the metal diaphragm extends from the sidewall of the resonant cavity into the interior of the resonant cavity.

[0012] Furthermore, the metal diaphragm is rectangular and its three sides are fixedly connected to the inner wall of the waveguide.

[0013] Furthermore, both the first adjustable pin assembly and the second adjustable pin assembly include a pin rod that passes through the wall of the waveguide.

[0014] Furthermore, one end of the pin rod is an adjustment end, which extends into the resonant cavity.

[0015] Furthermore, both the first and second adjustable pin assemblies include an adjusting nut, which is used to adjust the length of the adjusting end extending into the resonant cavity.

[0016] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0017] 1. The waveguide bandpass filter of this utility model, by setting a first adjustable pin assembly and a second adjustable pin assembly, can efficiently adjust the resonant frequency of the resonant cavity and the coupling degree between the resonant cavities, thereby improving the adjustability of the waveguide bandpass filter.

[0018] 2. The waveguide bandpass filter of this utility model adopts a combination of adjustable pins and metal diaphragms, which solves the problems of operating frequency offset and large in-band reflection caused by filter structure processing tolerances, and improves the adjustability of the waveguide bandpass filter.

[0019] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objectives and other advantages of this invention can be realized and obtained through the embodiments described and the accompanying drawings, which are particularly pointed out. Attached Figure Description

[0020] Figure 1 This is a three-dimensional perspective view of the waveguide bandpass filter according to an embodiment of the present invention;

[0021] Figure 2 This is a top view of the waveguide bandpass filter according to an embodiment of the present invention.

[0022] Figure 3 This is a side view of the waveguide bandpass filter according to an embodiment of the present invention.

[0023] Figure label:

[0024] 1-Waveguide; 11-Resonant cavity;

[0025] 2-Adjustable pin assembly; 21-First adjustable pin assembly; 22-Second adjustable pin assembly; 201-Pin rod; 202-Adjusting nut;

[0026] 3-Metallic membrane. Detailed Implementation

[0027] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0028] Example 1

[0029] This embodiment provides a waveguide bandpass filter based on an adjustable pin assembly and a metal diaphragm, such as Figure 1 and Figure 2 As shown, it includes a waveguide 1, an adjustable pin assembly 2, and a metal diaphragm 33; the waveguide 1 includes at least two resonant cavities 11 connected in sequence, and the metal diaphragm 3 is fixed at the connection between adjacent resonant cavities 11; the adjustable pin assembly 2 includes a first adjustable pin assembly 21 and a second adjustable pin assembly 22, the first adjustable pin assembly 21 is used to adjust the resonant frequency of the resonant cavity 11, and the second adjustable pin assembly 22 is used to adjust the coupling degree between the resonant cavities 11.

[0030] The waveguide bandpass filter in this embodiment adopts a combination of adjustable pins and metal diaphragms 3. The center frequency of the waveguide bandpass filter is changed by adjusting the first adjustable pin assembly 21, and the coupling bandwidth of the waveguide bandpass filter is changed by adjusting the second adjustable pin assembly 22. This solves the problems of operating frequency offset and large in-band reflection caused by filter structure processing tolerances, and improves the adjustability of the waveguide bandpass filter.

[0031] In some embodiments, such as Figure 2 As shown, the adjustable pin assemblies 2 are arranged sequentially at intervals along the length of the waveguide 1. The position of the first adjustable pin assembly 21 corresponds to the center of the resonant cavity 11, and the position of the second adjustable pin assembly 22 corresponds to the position of the metal diaphragm 3. This allows the first adjustable pin assembly 21 and the second adjustable pin assembly 22 to adjust the resonant frequency of the resonant cavity 11 and the coupling degree between the resonant cavities 11, respectively.

[0032] Specifically, such as Figure 2As shown, both the first adjustable pin assembly 21 and the second adjustable pin assembly 22 include a pin rod 201, which passes through the wall of the waveguide 1. The waveguide 1 includes a wide side and a narrow side, and the pin rod 201 is perpendicularly inserted through the wide side of the waveguide 1. One end of the pin rod 201 is an adjustment end, which extends into the resonant cavity 11 and can be adjusted axially to the depth of insertion into the resonant cavity 11. When the pin rod 201 of the first adjustable pin assembly 21 extends into the resonant cavity 11, the equivalent capacitance increases and the resonant frequency decreases. When the pin rod 201 of the second adjustable pin assembly 22 is positioned close to the metal diaphragm 3 and its insertion depth is adjusted, the electromagnetic coupling strength between adjacent resonant cavities 11 changes accordingly, thereby adjusting the passband bandwidth of the filter.

[0033] like Figure 3 As shown, both the first adjustable pin assembly 21 and the second adjustable pin assembly 22 also include an adjusting nut 202, which is used to adjust the length of the adjusting end extending into the resonant cavity 11. The adjusting nut 202 is located outside the waveguide 1 for easy adjustment.

[0034] In some embodiments, such as Figure 1 and Figure 3 As shown, the metal diaphragm 3 is rectangular and its three sides are fixedly connected to the inner wall of the waveguide 1. The metal diaphragms 3 are arranged in pairs on the narrow sides of the waveguide 1 and extend into the resonant cavity 11. The adjustment end of the second adjustable pin assembly 22 is located between the two pairs of metal diaphragms 3.

[0035] When scheduling the waveguide bandpass filter of this embodiment, firstly, adjust each adjustable pin to its designed depth within the resonant cavity 11, for example, L / 2. Then, test the S-parameter curve of the waveguide bandpass filter on a vector network analyzer. Compare the operating center frequency shown on the actual test curve with the design frequency, and increase or decrease the depth of the pin rod 201 of the first adjustable pin assembly 21 into the resonant cavity 11. Observe the frequency change displayed on the instrument. By adjusting the first adjustable pin assembly 21, ensure that the resonant frequencies of all resonant cavities 11 are within the operating frequency range. Then, adjust the depth of the pin rod 201 of the second adjustable pin assembly 22 into the waveguide 1 to change the coupling between adjacent resonant cavities 11, thereby improving reflections within the filter passband. After adjusting all adjustable pins by adjusting the nut 202, fix the adjustable pin assembly 2 with high and low temperature resistant waterproof adhesive.

[0036] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present utility model should be included within the protection scope of the present utility model.

Claims

1. A waveguide bandpass filter based on an adjustable pin assembly and a metal diaphragm, characterized in that, It includes a waveguide (1), an adjustable pin assembly (2), and a metal diaphragm (3); The waveguide (1) includes at least two resonant cavities (11) connected in sequence, and the metal diaphragm (3) is fixed at the connection between adjacent resonant cavities (11); The adjustable pin assembly (2) includes a first adjustable pin assembly (21) and a second adjustable pin assembly (22). The first adjustable pin assembly (21) is used to adjust the resonant frequency of the resonant cavity (11), and the second adjustable pin assembly (22) is used to adjust the coupling degree between the resonant cavities (11).

2. The waveguide bandpass filter based on an adjustable pin assembly and a metal diaphragm according to claim 1, characterized in that, The adjustable pin assembly (2) is arranged sequentially at intervals along the length of the waveguide (1).

3. The waveguide bandpass filter based on an adjustable pin assembly and a metal diaphragm according to claim 2, characterized in that, The position of the first adjustable pin assembly (21) corresponds to the center of the resonant cavity (11).

4. The waveguide bandpass filter based on an adjustable pin assembly and a metal diaphragm according to claim 3, characterized in that, The position of the second adjustable pin assembly (22) corresponds to the position of the metal diaphragm (3).

5. The waveguide bandpass filter based on an adjustable pin assembly and a metal diaphragm according to claim 4, characterized in that, The metal diaphragms (3) are arranged in pairs, and the second adjustable pin assembly (22) is located between the two pairs of metal diaphragms (3).

6. The waveguide bandpass filter based on an adjustable pin assembly and a metal diaphragm according to claim 5, characterized in that, The metal diaphragm (3) extends from the sidewall of the resonant cavity (11) into the interior of the resonant cavity (11).

7. The waveguide bandpass filter based on an adjustable pin assembly and a metal diaphragm according to claim 6, characterized in that, The metal diaphragm (3) is rectangular and its three sides are fixedly connected to the inner wall of the waveguide (1).

8. The waveguide bandpass filter based on an adjustable pin assembly and a metal diaphragm according to any one of claims 1 to 7, characterized in that, Both the first adjustable pin assembly (21) and the second adjustable pin assembly (22) include a pin rod (201), which passes through the wall of the waveguide (1).

9. The waveguide bandpass filter based on an adjustable pin assembly and a metal diaphragm according to claim 8, characterized in that, One end of the pin rod (201) is an adjustment end, which extends into the resonant cavity (11).

10. The waveguide bandpass filter based on an adjustable pin assembly and a metal diaphragm according to claim 9, characterized in that, The first adjustable pin assembly (21) and the second adjustable pin assembly (22) also include an adjusting nut (202), which is used to adjust the length of the adjusting end extending into the resonant cavity (11).

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