EP4195401A1

EP4195401A1 - Waveguide interface structure

Info

Publication number: EP4195401A1
Application number: EP21859988.4A
Authority: EP
Inventors: Zhuo Li; Jing Wang; Yong Zhang; Jianxun SHU; Zhen Zhang
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2020-08-31
Filing date: 2021-07-21
Publication date: 2023-06-14
Also published as: WO2022042148A1; EP4195401A4; JP7551903B2; JP2023538358A; CN114122644B; CN114122644A

Abstract

Embodiments of the present application relate to the technical field of microwave communications, and provide a waveguide interface structure. The waveguide interface structure (100) in the embodiments of the present application is configured for electrically connecting a first waveguide (10) and a second waveguide (20), and includes an electrical connection portion (11) with elasticity and a fixing portion (12) connected to the electrical connection portion (11). The fixing portion (12) is configured to abut against the end surface of the first waveguide (10). An opening for electromagnetic waves to pass is enclosed by the electrical connection portion (11). The electrical connection portion (11) is elastically pressed between an end surface of the first waveguide (10) and an end surface of the second waveguide (20), and the electrical connection portion is configured for electrically connecting the first waveguide (10) and the second waveguide (20).

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Chinese Patent Application No. 202010895432.9, filed on August 31, 2020 , the entire contents of which are incorporated herein by reference.

TECHNICAL FIELD

Embodiments of the present application relate to the technical field of microwave communications, and in particular to a waveguide interface structure.

BACKGROUND

In the microwave frequency band, the waveguide has the smallest transmission loss, and is an irreplaceable transmission line type for improving the sending and receiving sensitivity of the microwave communication system. When a gap exists in the waveguide interconnection, the strong radiation loss and interference will occur, and the normal operation of the system will be affected. In some cases, the waveguide interconnection solution mostly adopts a single waveguide port and the priority is to ensure the electrical connection. That is, the end surfaces of the two interconnected waveguide ports are in close contact. When a small interconnection gap exists in the waveguide interconnection, a shielding sealing ring is generally provided around the waveguide port to solve the problem about electromagnetic leakage.
The above-mentioned solution has at least following problems: requirements for processing and assembling the waveguide end surfaces are high, and the processing difficulty of the waveguide structure is relatively great. Moreover, the above-mentioned solution can only adapt to the situation of small interconnection gaps, and cannot adapt to the using situation of large gaps with random tolerances.

SUMMARY

The purpose of the embodiments in the present application is to provide a waveguide interface structure, which can reduce the processing difficulty of the waveguide structure and adapt to the using situation of large gaps with random tolerances under the premise that the signal in the waveguide interconnection channel can be ensured to transmit normally.
In order to solve the above technical problems, embodiments of the present application provide a waveguide interface structure, for electrically connecting a first waveguide and a second waveguide. The waveguide interface structure includes an electrical connection portion with elasticity and a fixing portion connected to the electrical connection portion. The fixing portion is configured to abut against the end surface of the first waveguide. An opening for electromagnetic waves to pass is enclosed by the electrical connection portion. The electrical connection portion is elastically pressed between an end surface of the first waveguide and an end surface of the second waveguide, and the electrical connection portion is configured for electrically connecting the first waveguide and the second waveguide.

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments are exemplified by pictures in the accompanying drawings, and these exemplifications are not intended to limit the embodiments. Elements in the drawings with the same reference numerals denote similar elements. Unless otherwise stated, and the pictures in the drawings are not limited to scale.

FIG. 1 is a schematic structural view of a waveguide interface structure according to a first embodiment of the present application.
FIG. 2 is a schematic structural view of the waveguide interface structure applied to a waveguide according to the first embodiment of the present application.
FIG. 3 is an assembly view of the waveguide interface structure applied to the waveguide according to the first embodiment of the present application.
FIG. 4 is another schematic structural view of the waveguide interface structure according to the first embodiment of the present application.
FIG. 5 is another schematic structural view of the waveguide interface structure applied to the waveguide according to the first embodiment of the present application.
FIG. 6 is another assembly view of the waveguide interface structure applied to the waveguide according to the first embodiment of the present application.
FIG. 7 is yet another schematic structural view of the waveguide interface structure according to the first embodiment of the present application.
FIG. 8 is yet another schematic structural view of the waveguide interface structure applied to the waveguide according to the first embodiment of the present application.
FIG. 9 is yet another assembly view of the waveguide interface structure applied to the waveguide according to the first embodiment of the present application.
FIG. 10 is a schematic structural view of the waveguide interface structure according to a second embodiment of the present application.
FIG. 11 is a schematic structural view of the waveguide interface structure applied to the waveguide according to the second embodiment of the present application.
FIG. 12 is yet another assembly view of the waveguide interface structure applied to the waveguide according to the first embodiment of the present application.

DETAILED DESCRIPTION OF THE EMBODIMENTS

In order to make the objectives, technical solutions and advantages of the embodiments of the present application clearer, each embodiment of the present application will be described in detail below with reference to the accompanying drawings. However, those of ordinary skill in the art can understand that, in each embodiment of the present application, many technical details are provided for the reader to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in the present application can be realized.
As shown in FIG. 1 to FIG. 9, a first embodiment of the present application relates to a waveguide interface structure 100, for electrically connecting a first waveguide 10 and a second waveguide 20. The core of this embodiment is that the waveguide interface structure 100 includes an electrical connection portion 11 with elasticity and a fixing portion 12 connected to the electrical connection portion 11. An opening 30 for electromagnetic waves to pass is enclosed by the electrical connection portion 11. The electrical connection portion 11 is elastically pressed between an end surface of the first waveguide 10 and an end surface of the second waveguide 20, and the electrical connection portion 11 is configured for electrically connecting the first waveguide 10 and the second waveguide 20. The fixing portion 12 is configured to abut against the end surface of the first waveguide 10.
The electrical connection portion 11 has elasticity, and is elastically pressed between the end surface of the first waveguide 10 and the end surface of the second waveguide 20. Therefore, the electrical connection portion 11 can be elastically deformed according to the size of the gap between the end surface of the first waveguide 10 and the end surface of the second waveguide 20. Since the electrical connection portion 11 is configured for electrically connecting a first waveguide 10 and a second waveguide 20, the gap between the first waveguide 10 and the second waveguide 20 can be absorbed by the electrical connection portion 11 (that is, an opening 30 for electromagnetic waves to pass is enclosed by the electrical connection portion 11, the electromagnetic wave leakage at the gap between the first waveguide 10 and the second waveguide 20 can be avoided, and the gap between the first waveguide 10 and the second waveguide 20 can be compensated). In this way, not only the problem of non-coplanar interconnection between a plurality of waveguide ports can be solved, but also the electromagnetic wave leakage can be avoided, and the normal signal transmission in the waveguide interconnection channel can be ensured. Moreover, the influence of the cumulative tolerance on the waveguide interconnection is little. Not only the processing accuracy and the assembly requirements of each end surface on the waveguide are low, but also each waveguide port channel can be processed independently, which reduces the processing difficulty of the waveguide structure, and can adapt to the using situation of large gaps with random tolerances.
Moreover, in the related art, the connection of the waveguide port is firstly ensured, then the waterproofing and heat dissipation of the casing is considered, which limits the architecture solution of the whole system, such as the stacking sequence of the whole machine structure, the waveguide port number of the whole machine, the position of the heat sink, the size of the waterproof sealing ring, and the like. In the embodiment of the present application, the first waveguide 10 is connected to the second waveguide 20 through the above-mentioned waveguide interface structure 100, and the waveguide interface structure 100 can be elastically deformed according to the size of the gap between the first waveguide 10 and the second waveguide 20, to absorb waveguide gaps of different sizes. In this way, there is no need to ensure the connection of the waveguide port first, and the heat sink can be designed on the outside of the whole machine and the antenna feeder to achieve the best heat dissipation effect, thereby effectively reducing the volume of the whole machine and costs. In addition, not only the waterproof surface of the whole machine structure can be ensured to contact firstly, and the sealing reliability of the whole machine can be improved, but also the mechanical strength of the docking between the whole machine and the antenna feeder can be improved. Further, the reliability risk of the external field and the later maintenance cost can be reduced.
Implementation details of the waveguide interface structure 100 in this embodiment will be described in detail below, and the following contents are the implementation details only for the convenience of understanding, and are not necessary for implementing this solution.
In practical applications, the electrical connection portion 11 may include an annular body portion 111 connected to the fixing portion 12 and a plurality of elastic pieces 112 provided on the annular body portion 111 at intervals. The annular body portion 111 is configured to attach to the end surface of the first waveguide 10. The plurality of elastic pieces 112 are configured to abut against the end surface of the second waveguide 20, and the plurality of elastic pieces 112 extends along a direction away from the annular body portion 111 to jointly enclose the opening 30. The opening 30 is provided opposite to a central through hole of the annular body portion 111, to facilitate the transmission of electromagnetic waves. A plurality of elastic pieces 112 are elastically pressed between the end surfaces of the first waveguide 10 and the end surface of the second waveguide 20, and electrically connect the first waveguide 10 and the second waveguide 20. In this way, the large-surface contact is transformed into multi-point contact, thereby effectively avoiding the problem of poor contact in a large area, and reducing the processing accuracy and assembly requirements of the elastic pieces 112.
In order to meet the signal transmission requirements, the size of the opening 30 can change according to the size of the waveguide interconnection gap and the deformation of the elastic piece 112, as long as the electrical performance of the opening 30 size always matches with the electrical performance of the waveguide size. The waveguide interface structure 100 can be applied to application scenarios such as rectangular waveguides, circular waveguides, ridge waveguides, and the like. The elastic piece 112 can be designed as a broadband, whose operating frequency range is consistent with that of the waveguide. Different central opening 30s are designed according to different waveguide types. For rectangular waveguides, the opening 30 can be a rectangular. For circular waveguides, the opening 30 can be a circular. For ridge waveguides, the opening 30 can be ridge-shaped.
The annular body portion 111 can be made of a conductive material, such as metal. The elastic piece 112 may be made of an elastic conductive material, such as metal. Of course, the surfaces of the annular body portion 111 and the elastic piece 112 can be made of conductive materials, while the inner materials of the annular body portion 111 and the elastic piece 112 can be insulating materials (such as plastic), as long as the first waveguide 10 can be electrically connected to the second waveguide 20 through the annular body portion 111 and the elastic piece 112.
In practical applications, the elastic piece 112 can be folded into shape after stamping or etching. The planar metal sheet can be bent into a cylindrical shape firstly, and then be weld into the cylindrical isolation portion 114. In order to reduce the processing difficulty, the elastic piece 112 and the cylindrical isolation portion 114 can be processed separately, and then welded together. In the waveguide interface structure 100 of this embodiment, the material cost is low, and the waveguide interface structure 100 is easy to process and can be mass-produced through molds. Compared with the conductive rubber ring, the waveguide interface structure 100 of this embodiment has advantages in cost.
In this embodiment, each elastic piece 112 may include a first extension portion 112a connected to the annular body portion 111, and a second extension portion 112b bending and extending from the first extension portion 112a. The second extension portion 112b is configured to abut against the end surface of the second waveguide 20. The second extension portion 112b bends and extends from the first extension portion 112a, to make the junction between the first extension portion 112a and the second extension portion 112b more likely to be elastically deformed, so that the junction can better adapt to gaps of different sizes between the first waveguide 10 and the second waveguide 20.
The first extension portion 112a can be provided on an inner edge 111a of the annular body portion 111. Or the first extension portion 112a can be provided on an outer edge 111b of the annular body portion 111. Or a part of the first extension portion 112a can be provided on the inner edge 111a of the annular body portion 111, and another part of the first extension portion 112a can be provided on the outer edge 111b of the annular body portion 111. Of course, the first extension portion 112a may not be provided at the edge of the annular body portion 111, but between the inner edge and the outer edge, which is not limited herein.
For each elastic piece 112, an obtuse angle, an acute angle or a right angle can be set between the second extension portion 112b and the first extension portion 112a (that is, the angle between the second extension portion 112b and the first extension portion 112a can be an obtuse angle, an acute angle or a right angle). The junction between the second extension portion 112b and the first extension portion 112a is configured to abut against the end surface of the second waveguide 20. Or an end of the second extension portion 112b away from the first extension portion 112a is configured to abut against the end surface of the second waveguide 20.
All the elastic pieces 112 can be set in a same way. For example, an obtuse angle, an acute angle or a right angle can be set between each second extension portion 112b and the corresponding first extension portion 112a. Or elastic pieces 112 set in various ways can be assembled, and each elastic piece 112 can be set in any of the above-mentioned ways. For example, an obtuse angle can be set between a part of the second extension portion 112b and the corresponding first extension portion 112a, and an acute angle can be set between another part of the second extension portion 112b and the corresponding first extension portion 112a.
For the convenience of understanding, two examples are illustrated in the following.
As shown in FIG. 1, FIG. 2 and FIG. 3, the first extension portion 112a is provided on the inner edge 111a of the annular body portion 111, and an obtuse angle can be set between the second extension portion 112b and the first extension portion 112a. The junction between the second extension portion 112b and the first extension portion 112a is configured to abut against the end surface of the first waveguide 10, and an end of the second extension portion 112b away from the first extension portion 112a is configured to abut against the end surface of the second waveguide 20.
As shown in FIG. 4, FIG. 5 and FIG. 6, a part of the first extension portion 112a is provided on the inner edge 111a of the annular body portion 111, and another part of the first extension portion 112a is provided on the outer edge 111b of the annular body portion 111. Moreover, an acute angle can be set between the second extension portion 112b and the first extension portion 112a. The junction between the second extension portion 112b and the first extension portion 112a is configured to abut against the end surface of the first waveguide 10, and an end of the second extension portion 112b away from the first extension portion 112a is configured to abut against the end surface of the second waveguide 20.
As shown in FIG. 7, FIG. 8, and FIG. 9, the first extension portion 112a are provided on the inner edge 111a of the annular body portion 111. An obtuse angle can be set between a part of the second extension portion 112b and the corresponding first extension portion 112a, and an acute angle can be set between another part of the second extension portion 112b and the corresponding first extension portion 112a. The junction between the second extension portion 112b and the first extension portion 112a is configured to abut against the end surface of the first waveguide 10, and an end of the second extension portion 112b away from the first extension portion 112a is configured to abut against the end surface of the second waveguide 20.
In order to ensure the reliable contact and the electrical performance within the tolerance range, the finger width, the finger spacing, the finger length and the shape of the elastic piece 112 are designed through simulation. The finger width needs to consider the elastic force and deformation of the material (the smaller the finger width, the better the elasticity), to ensure good contact at all times under different gap sizes. The finger spacing meets the cutoff waveguide theory and is reasonably designed according to the anti-leakage target. The tolerance absorption capacity (adaptability to the gap size of the waveguides) and the electrical performance are determined by the finger length and the shape.
If the above-mentioned waveguide interface structure 100 is suitable for transmitting a waveguide of the electromagnetic waves with a first wavelength (the opening 30 is configured for electromagnetic waves with a first wavelength to pass). That is, the first waveguide 10 and the second waveguide 20 are configured for transmitting electromagnetic waves with a first wavelength, and the length of the contact surface between the elastic piece 112 and the waveguide is determined by the finger width. In order to ensure reliable electrical contact, along a distribution direction of the elastic pieces 112, a width w of the elastic piece 112 (namely the finger width) may be less than 0.2 times of the first wavelength. According to the anti-leakage target and the cutoff waveguide theory, along the distribution direction of the elastic pieces 112, a spacing v between adjacent elastic pieces 112 (namely the finger spacing) may be less than 0.05 times of the first wavelength. In order to ensure sufficient elasticity, the thickness of the elastic piece 112 is generally less than 0.2 mm.
In practical applications, installation holes 13 can be provided on the fixing portion 12, and screws can be inserted into the installation holes 13 and fixed on one end of the waveguide (that is, the first waveguide 10), thereby realizing the installation of the waveguide interface structure 100.
For the waveguide interface structure 100 in this embodiment, the gap absorption capacity can be 0 to 2 mm. That is, when the distance between the end surface of the first waveguide 10 and the end surface of the second waveguide 20 is within 2 mm, the waveguide interface structure 100 can realize a good electrical connection and the effect of preventing electromagnetic wave leakage.
A second embodiment of the present application relates to a waveguide interface structure 200. As shown in FIG. 10, FIG. 11 and FIG. 12, the second embodiment is substantially the same as the first embodiment, and the main difference is that: in the first embodiment, the electrical connection portion 11 includes an annular body portion 111 connected to the fixing portion 12 and a plurality of elastic pieces 112 provided on the annular body portion 111 at intervals. The annular body portion 111 is configured to attach to the end surface of the first waveguide 10, and the plurality of elastic pieces 112 extends along a direction away from the annular body portion 111 to jointly enclose the opening 30. The plurality of elastic pieces 112 are configured to abut against the end surface of the second waveguide 20. However, in the second embodiment of the present application, the electrical connection portion 11 includes a plurality of elastic pieces 113 provided on the fixing portion 12 at intervals and a cylindrical isolation portion 114 connected to the plurality of elastic pieces 113. The elastic piece 113 is configured to abut against the end surface of the second waveguide 20, and the opening 30 is enclosed by the cylindrical isolation portion 114. In addition, the cylindrical isolation portion 114 is configured to contact an inner wall of the first waveguide 10. The technical effect of this embodiment is similar to that of the first embodiment, which will not be repeated herein.
That is, in the first embodiment, the annular body portion 111 and the plurality of elastic pieces 113 are configured to respectively abut against the end surface of the first waveguide 10 and the end surface of the second waveguide 20, to realize the elastic connection and electrical connection between the first waveguide 10 and the second waveguide 20. In the second embodiment, the fixing portion 12 and a plurality of elastic pieces 113 are configured to respectively abut against the end surface of the first waveguide 10 and the end surface of the second waveguide 20, to realize the elastic connection between the first waveguide 10 and the second waveguide 20. Moreover, the cylindrical isolation portion 114 is connected to a plurality of elastic pieces 113 and configured to contact an inner wall of the first waveguide 10, to realize the electrical connection between the first waveguide 10 and the second waveguide 20.
The implementation details of the waveguide interface structure 200 of this embodiment will be described detailedly below, and the following contents are the implementation details only for the convenience of understanding, and are not necessary for implementing this solution.
The cylindrical isolation portion 114 may include a cylindrical wall 114a connected to the plurality of the elastic pieces 113 and a plurality of abutting portions 114b connected to the cylindrical wall 114a. The free end of the abutting portion 114b is configured to abut against the inner wall of the first waveguide 10. That is, two opposite end edges (edges at both ends) are provided on the cylindrical isolation portion 114 along the axial direction of the cylindrical isolation portion 114. The elastic piece 113 is connected to one end edge (the top edge), and the abutting portion 114b is connected to the other end edge (the bottom edge). The large-surface contact is transformed into multi-point contact, which effectively avoids the problem of poor contact in a large area, and reduces the processing accuracy and assembly requirements of the abutting portion 114b.
In this embodiment, the abutting portion 114b extends from an end edge or an outer wall surface of the cylinder wall towards a direction away from an inner space of the cylinder wall. In this way, when the first waveguide 10 is connected to the second waveguide 20 through the waveguide interface structure 200, the cylinder wall extends into the waveguide port of the first waveguide 10, the abutting portion 114b abuts against the inner wall of the first waveguide 10, the elastic piece 113 abuts against the end surface of the second waveguide 20, and the elastic piece 113 is connected to the abutting portion 114b through the cylinder wall, thereby realizing the electrical connection between the first waveguide 10 and the second waveguide 20. Moreover, when the size of the interconnection gap between the first waveguide 10 and the second waveguide 20 changes, the abutting portion 114b slides on the inner wall of the first waveguide 10, keeping the abutting portion 114b in contact with the inner wall of the first waveguide 10. In addition, the electromagnetic wave in the electromagnetic wave transmission channel is isolated by the cylinder wall and the abutting portion 114b, thereby avoiding the problem of electromagnetic wave leakage.
In this embodiment, each elastic piece 113 includes a first extension portion 113a connected to the fixing portion 12, a second extension portion 113b bending and extending from the first extension portion 113a, and a third extension portion 113c bending and extending from the second extension portion 113b. The third extension portion 113c is connected to the cylindrical isolation portion 114, and the third extension portion 113c is configured to abut against the end surface of the second waveguide 20. The third extension portion 113c is connected to an end edge (the top edge) of the cylindrical wall 114a, and the abutting portion 114b is connected to the other end edge (the bottom edge) of the cylindrical wall 114a. Since the second extension portion 113b bends and extends from the first extension portion 113a, the junction between the first extension portion 113a and the second extension portion 113b is more likely to be elastically deformed, thereby better adapting to different sizes of gaps between the first waveguide 10 and the second waveguide 20.
It can be understood that the elastic piece 113 can have other elastic structures, such as a spring, as long as the elastic pieces 113 can be elastically pressed between the end surface of the first waveguide 10 and the end surface of the second waveguide 20, which is not limited herein.
The material, the manufacturing method and the size of the abutting portion 114b are similar to those of the elastic piece 112 in the first embodiment. For example, the abutting portion 114b can be made of a metal material, which can be bent and welded after stamping or etching (the cylinder wall and the abutting portion 114b are molded together), or the abutting portion 114b is welded to the cylinder wall by a welding process. If the opening 30 is configured for the electromagnetic wave with the first wavelength to pass, in order to ensure a reliable electrical contact, along a distribution direction of the abutting portion 114b, a width w of the abutting portion 114b (namely the finger width) may be less than 0.2 times of the first wavelength. According to the anti-leakage target and the cutoff waveguide theory, along a distribution direction of the abutting portion 114b, a spacing v between adjacent abutting portions 114b (namely the finger spacing) may be less than 0.05 times of the first wavelength, and the setting of other dimensions will not be repeated herein.
In practical applications, the third extension portion 113c and the cylindrical isolation portion 114 (specifically, the cylindrical wall 114a and the abutting portion 114b) may be made of conductive materials, such as metal. In this way, an electrical connection between the first waveguide 10 and the second waveguide 20 can be realized through the third extension portion 113c, the cylinder wall and the abutting portion 114b. Of course, the surfaces of the third extension portion 113c, the cylinder wall and the abutting portion 114b can be made of conductive materials, while the inner materials of the third extension portion 113c, the cylinder wall and the abutting portion 114b can be insulating materials (such as plastic), as long as the electrical connection can be realized.
In the waveguide interface structure 200 provided in this embodiment, the gap absorption capacity is greater than 2 mm. That is, when the distance between the end surface of the first waveguide 10 and the end surface of the second waveguide 20 is more than 2 mm, the waveguide interface structure 200 can achieve a good electrical connection and the effect of preventing electromagnetic wave leakage.
Since the first embodiment corresponds to this embodiment, this embodiment can be implemented in cooperation with the first embodiment. The relevant technical details mentioned in the first embodiment are still valid in this embodiment, and the technical effects that can be achieved in the first embodiment can further be realized in this embodiment. In order to reduce repetition, details are not repeated herein. Correspondingly, the relevant technical details mentioned in this embodiment can further be applied in the second embodiment.
Those of ordinary skill in the art can understand that the above-mentioned embodiments are specific embodiments for realizing the present application. However, in practical application, various changes in form and details may be made therein without departing from the scope of the present application.

Claims

A waveguide interface structure, for electrically connecting a first waveguide and a second waveguide, characterized by comprising:
an electrical connection portion with elasticity, wherein an opening for electromagnetic waves to pass is enclosed by the electrical connection portion, the electrical connection portion is elastically pressed between an end surface of the first waveguide and an end surface of the second waveguide, and the electrical connection portion is configured for electrically connecting the first waveguide and the second waveguide; and

a fixing portion connected to the electrical connection portion, wherein the fixing portion is configured to abut against the end surface of the first waveguide.
The waveguide interface structure of claim 1, wherein the electrical connection portion comprises:
an annular body portion connected to the fixing portion, wherein the annular body portion is configured to attach to the end surface of the first waveguide; and

a plurality of elastic pieces provided on the annular body portion at intervals, wherein the plurality of elastic pieces extends along a direction away from the annular body portion, the opening is enclosed by the plurality of elastic pieces, and the plurality of elastic pieces are configured to abut against the end surface of the second waveguide.
The waveguide interface structure of claim 2, wherein each elastic piece comprises:
a first extension portion connected to the annular body portion; and

a second extension portion bending and extending from the first extension portion, and the second extension portion is configured to abut against the end surface of the second waveguide.
The waveguide interface structure of claim 3, wherein:
the first extension portion is provided on an inner edge of the annular body portion; or

the first extension portion is provided on an outer edge of the annular body portion; or

a part of the first extension portion is provided on an inner edge of the annular body portion, and another part of the first extension portion is provided on an outer edge of the annular body portion.
The waveguide interface structure of claim 3, wherein:
an obtuse angle is set between the second extension portion and the first extension portion; or

an acute angle is set between the second extension portion and the first extension portion; or

an obtuse angle is set between a part of the second extension portion and the first extension portion, and an acute angle is set between another part of the second extension portion and the first extension portion.
The waveguide interface structure of claim 2, wherein:
the opening is configured for the electromagnetic wave with a first wavelength to pass;

along a distribution direction of the elastic pieces, a width of the elastic piece is less than 0.2 times of the first wavelength; and/or

a spacing between adjacent elastic pieces is less than 0.05 times of the first wavelength.
The waveguide interface structure of claim 2, wherein the annular body portion is made of a conductive material, and the elastic piece is made of an elasticity conductive material.
The waveguide interface structure of claim 1, wherein the electrical connection portion comprises:
a plurality of elastic pieces provided on the fixing portion at intervals, wherein the elastic piece is configured to abut against the end surface of the second waveguide; and

a cylindrical isolation portion connected to the plurality of elastic pieces, wherein the opening is enclosed by the cylindrical isolation portion, and the cylindrical isolation portion is configured to contact an inner wall of the first waveguide.
The waveguide interface structure of claim 8, wherein the cylindrical isolation portion comprises:
a cylindrical wall connected to the plurality of the elastic pieces; and

a plurality of abutting portions connected to the cylindrical wall, wherein the abutting portion is configured to abut against the inner wall of the first waveguide.
The waveguide interface structure of claim 9, wherein the abutting portion extends from an end edge or an outer wall surface of the cylinder wall towards a direction away from an inner space of the cylinder wall.
The waveguide interface structure of claim 9, wherein:
the opening is configured for electromagnetic waves with a first wavelength to pass;

along a distribution direction of the elastic pieces, a width of the abutting portion is less than 0.2 times of the first wavelength; and/or

a spacing between adjacent abutting portions is less than 0.05 times of the first wavelength.
The waveguide interface structure of claim 8, wherein each elastic piece comprises:
a first extension portion connected to the fixing portion;

a second extension portion bending and extending from the first extension portion; and

a third extension portion bending and extending from the second extension portion, wherein the third extension portion is connected to the cylindrical isolation portion, and the third extension portion is configured to abut against the end surface of the second waveguide.
The waveguide interface structure of claim 12, wherein both the third extension portion and the cylindrical isolation portion are made of conductive materials.