CN219180752U

CN219180752U - Feedback millimeter wave waveguide coaxial converter

Info

Publication number: CN219180752U
Application number: CN202320146643.1U
Authority: CN
Inventors: 孙博雅; 康甜甜
Original assignee: Shaanxi Huada Science Technology Co Ltd
Current assignee: Shaanxi Huada Science Technology Co Ltd
Priority date: 2023-01-28
Filing date: 2023-01-28
Publication date: 2023-06-13
Anticipated expiration: 2033-01-28

Abstract

The utility model discloses a feedback millimeter wave waveguide coaxial converter, which belongs to the technical field of waveguide coaxial conversion equipment, and comprises a waveguide body and a coaxial connector, wherein: the middle part of the waveguide body is provided with a waveguide upper cavity and a waveguide lower cavity, the inner surface of the waveguide lower cavity is provided with a ridge waveguide impedance matching section, the ridge waveguide impedance matching section is a stepped impedance matching section, and the coaxial connector comprises an outer conductor, an inner conductor, a bushing and an insulating support sleeve. Compared with the prior structure, the structure adopts a multistage ladder impedance transformation structure in a standard caliber waveguide cavity and is combined with a coaxial probe feedback type coupling structure, the designed ridge waveguide impedance matching section can improve standing wave performance, low-loss transition of microwave signals from a waveguide system to a coaxial system or from the coaxial system to the waveguide system is realized, a welding step and an additional tuning step are not needed in the whole design and manufacturing process, the process complexity and the production cost of a product are reduced, and meanwhile, the consistency of the product is improved.

Description

Feedback millimeter wave waveguide coaxial converter

Technical Field

The utility model belongs to the technical field of waveguide coaxial conversion equipment, and particularly relates to a feedback millimeter wave waveguide coaxial converter.

Background

The waveguide coaxial converter is a passive conversion device widely used in modern microwave millimeter wave systems, plays an indispensable role in various radar systems, precision guidance systems and testing fields, is commonly used for signal interconnection between a transceiver module and an array antenna in an active phased array antenna system, and generally achieves the function of converting rectangular waveguide into coaxial line.

At present, a coaxial waveguide converter generally adopts a side-feed structure, and the principle is that an inner conductor of a coaxial line is vertically extended and inserted into a rectangular waveguide cavity, a probe inserted into the cavity is equivalent to an antenna, energy transmitted by the coaxial line is radiated out through the head of the probe, and an electromagnetic field is excited in the waveguide so as to complete energy exchange between the probe and the waveguide. The structure body is divided into a coaxial end, a waveguide upper cavity and a waveguide lower cavity, wherein the inner conductor of the coaxial line is vertically extended and inserted into the rectangular waveguide cavity, and the purpose of widening the frequency band can be realized by adjusting the insertion depth of the probe and the radius size of the probe and adopting a gradual change method to the probe head inserted into the waveguide.

In practical application, the conventional coaxial waveguide converter has the following technical defects:

1) The insertion of the coaxial probe causes a discontinuity in the waveguide, which in turn produces an infinite number of higher order modes, while the waveguide can only transmit the main mode, and the higher order modes that cannot transmit collect around the probe to produce a reactive effect.

2) Because one end of the waveguide port is a short circuit board, electromagnetic energy can only be transmitted towards the other port of the waveguide, so that the transmission directivity is relatively strong, the lateral feed type analysis method is mainly a mode matching idea, in order to enable the adapter to achieve good matching in a wider frequency range, the purpose of widening the frequency band can be achieved by adjusting the insertion depth of the probe and the radius size of the probe, and the purpose of widening the frequency band can also be achieved by gradually changing the probe head inserted into the waveguide, but the irregular probe shape can complicate the calculation of the surface current distribution.

3) When the power is high, the top of the probe is easy to break down, and because the coaxial joint and the waveguide form an included angle of 90 degrees, the input port and the output port of the side-feed structure are not on the same horizontal line, which is unfavorable for cascading between systems, and the structure is not compact enough.

4) In the millimeter wave frequency range application range, the aperture size of the waveguide port is smaller, and the change of the relevant critical dimension of the side-fed coaxial probe is very sensitive to the influence of the conversion performance of the waveguide coaxial converter, so that the processing and manufacturing process is challenged.

Disclosure of Invention

Aiming at the technical problems, the utility model provides a feedback millimeter wave waveguide coaxial converter, which adopts a multistage ladder impedance conversion structure in a standard caliber waveguide cavity and is combined with a coaxial probe feedback coupling structure, the designed ridge waveguide impedance matching section can improve standing wave performance, low-loss transition of microwave signals from a waveguide system to a coaxial system or from the coaxial system to the waveguide system is realized, a welding step and an additional tuning step are not needed in the whole design and manufacturing process, the process complexity and the production cost of a product are reduced, and the consistency of the product is improved.

The utility model solves the problems by the following technical means:

a feed-back millimeter wave waveguide coaxial converter comprising a waveguide body and a coaxial connector, wherein: the middle part of the waveguide body is provided with a waveguide upper cavity and a waveguide lower cavity, the inner surface of the waveguide lower cavity is provided with a ridge waveguide impedance matching section, the ridge waveguide impedance matching section is a step impedance matching section, and the connecting end face of the waveguide body is provided with a connecting countersink; the coaxial connector comprises an outer conductor, an inner conductor, a bushing and an insulating support sleeve, wherein a central hole is formed in the center of the outer conductor, a step hole is formed in the tail end of the central hole, the bushing is installed in the step hole, the insulating support sleeve is coaxially arranged in the bushing, the inner conductor is installed in the central hole of the insulating support sleeve, and the outer end of the inner conductor is connected with a connecting countersunk hole in a matched mode.

Preferably, the height of the ridge waveguide impedance matching section gradually decreases from one closed end of the waveguide body to the other end in a stepped manner, the length of each step is 1/3λ to 1/4λ, and the thickness of each step is 0.04 λ to 0.1λ.

Preferably, the waveguide body is further provided with a joint inner cavity communicating with the central hole.

Preferably, a connecting flange is arranged at the bottom of the waveguide body, and a plurality of threaded holes are symmetrically formed in the connecting flange.

Preferably, one end of the inner conductor is provided with a slot splitting jack, and the other end of the inner conductor is provided with a slot splitting plug.

Preferably, the tail end of the outer conductor is turned to form a connecting disc, and a plurality of mounting screws are arranged on the connecting disc.

Preferably, the insulating support sleeve is symmetrically provided with a plurality of side holes, and the side holes are used for adding air medium.

The utility model provides a feedback millimeter wave waveguide coaxial converter which can effectively solve the technical problems of the prior coaxial waveguide converter and has the following beneficial effects:

the structure adopts a multistage stepped impedance transformation structure in a standard caliber waveguide cavity and is combined with a coaxial probe feedback type coupling structure, the designed ridge waveguide impedance matching section can improve standing wave performance, low-loss transition of microwave signals from a waveguide system to a coaxial system or from the coaxial system to the waveguide system is realized, a welding step and an additional tuning step are not needed in the whole design and manufacturing process, the process complexity and the production cost of a product are reduced, and meanwhile, the consistency of the product is improved. In addition, the structure adopts the threaded hole to be in threaded connection with the coaxial end and the lower cavity of the waveguide, so that the coaxial inner conductor can be prevented from loosening. The stepped impedance conversion mode in the scheme is beneficial to improving the standing wave performance of products, and the coaxial probe is inserted into the waveguide cavity from the rear wall of the rectangular waveguide, so that the problem of interconnection between systems is effectively solved, and the compactness of the structure is improved.

Drawings

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

FIG. 1 is a schematic view of the overall structure of the present utility model;

FIG. 2 is a schematic illustration of the connection of the present utility model;

fig. 3 is a schematic view of the coaxial connector structure of the present utility model.

Wherein, the liquid crystal display device comprises a liquid crystal display device, 1-waveguide, 101-waveguide upper cavity, 102-waveguide lower cavity, 103-ridge waveguide impedance matching section, 104-connection countersink, 105-connection flange, 106-threaded hole, 2-coaxial connector, 201-outer conductor, 202-inner conductor, 203-bushing, 204-insulating support sleeve, 205-center hole, 206-step hole, 207-connector inner cavity, 208-split slot jack, 209-split slot plug, 210-connection disk, 211-mounting screw, 212-side hole.

Detailed Description

In the description of the present utility model, it should be understood that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like indicate orientations or positional relationships based on the orientation or positional relationships shown in the drawings, merely to facilitate describing the present utility model and simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model. The terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present utility model, unless otherwise indicated, the meaning of "a plurality" is two or more.

The present utility model will be described in detail below with reference to the accompanying drawings.

As shown in fig. 1 to 3, the feedback millimeter wave waveguide coaxial converter comprises a waveguide body 1 and a coaxial connector 2, wherein a waveguide upper cavity 101 and a waveguide lower cavity 102 are formed in the middle of the waveguide body 1, the waveguide upper cavity 101 and the waveguide lower cavity 102 are integrally processed by adopting brass materials, the waveguide upper cavity 101 is a semicircular hole with a smooth inner wall, the left side of the waveguide lower cavity 102 is a semicircular hole with a smooth inner wall, a ridge waveguide impedance matching section 103 is arranged on the inner wall of the right side of the waveguide lower cavity 102, the ridge waveguide impedance matching section 103 is a stepped impedance matching section, and a connecting countersink 104 is arranged at the connecting end face of the waveguide body 1.

The height of the ridge waveguide impedance matching section 103 gradually decreases in a stepwise manner from the closed end of the waveguide body 1 to the other end, the length of each step is 1/3λ to 1/4λ, and the thickness of each step is 0.04 λ to 0.1λ. In actual operation, an initial reference value of the impedance transformation transition section is obtained through theoretical calculation, and then optimization and debugging are carried out through electromagnetic simulation software, so that impedance matching is optimal.

In the figure, the coaxial connector 2 comprises an outer conductor 201, an inner conductor 202, a bushing 203 and an insulating support sleeve 204, wherein the outer conductor 201 and the bushing 203 are integrally processed by stainless steel materials, the inner conductor 202 is integrally processed by beryllium bronze materials, the insulating support sleeve 204 is integrally processed by polyimide materials, a central hole 205 is formed in the center of the outer conductor 201, a stepped hole 206 is formed in the tail end of the central hole 205, the bushing 203 is installed in the stepped hole 206, the insulating support sleeve 204 is coaxially arranged in the bushing 203, the inner conductor 202 is installed in a central hole of the insulating support sleeve 204, and the outer end of the inner conductor 202 is connected with the connecting counter sunk hole 104 in a matched mode.

The waveguide 1 is further provided with a joint inner cavity 207 communicating with the center hole 205. The bottom of the waveguide body 1 is provided with a connecting flange 105, and a plurality of threaded holes 106 are symmetrically arranged on the connecting flange 105. One end of the inner conductor 202 is provided with a split slot jack 208, the other end of the inner conductor 202 is provided with a split slot plug 209, and the outer conductor and the inner conductor are standard 2.4 radio frequency coaxial connector interfaces, which meet the requirements of GJB 5246.

In this embodiment, the terminal flange of the outer conductor 201 forms a land 210, and a plurality of mounting screws 211 are provided on the land 210, and the mounting screws 211 are mounted on mounting holes at the connection end face of the waveguide 1. In addition, a plurality of side holes 212 are symmetrically formed on the insulating support sleeve 204, and the side holes 212 are used for adding air medium.

It should be further explained that the feed-back structure ensures that the input port of the coaxial line and the output port of the waveguide are arranged on the same horizontal line, the inner conductor at the same axial end and the ridge waveguide impedance transformation section are kept in insertion and close contact, and the reliability of electric contact can be realized; the impedance matching of the coaxial waveguide is realized by adding the single-ridge waveguide between the coaxial end and the waveguide, the single-ridge waveguide impedance transformation section is a key structure of the feedback waveguide coaxial converter, and the impedance value of the waveguide coaxial converter is regulated by utilizing the multi-section stepped impedance transformation of the single-ridge waveguide impedance transformation section, so that the better impedance matching is realized. The design scheme of the wave-to-common converter provided by the scheme can be applied to the design of other similar wave-to-common converters. On the premise of keeping the transmission impedance of the connector to 50 omega, a new waveguide coaxial converter can be designed by changing the step size in the waveguide cavity and by means of the transmission section structure of the scheme. The waveguide coaxial converter provided by the scheme not only can be applied to airborne equipment, but also can provide modularization and light-weight support for the airborne equipment, ground fixed equipment and a phased array antenna system.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present utility model, and are not limiting; although the utility model has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present utility model.

Claims

1. A feed-back millimeter wave waveguide coaxial converter, characterized by comprising a waveguide body (1) and a coaxial connector (2), wherein:

the middle part of the waveguide body (1) is provided with a waveguide upper cavity (101) and a waveguide lower cavity (102), the inner surface of the waveguide lower cavity (102) is provided with a ridge waveguide impedance matching section (103), the ridge waveguide impedance matching section (103) is a step-type impedance matching section, and the connecting end face of the waveguide body (1) is provided with a connecting countersink (104);

the coaxial connector (2) comprises an outer conductor (201), an inner conductor (202), a bushing (203) and an insulating support sleeve (204), wherein a central hole (205) is formed in the center of the outer conductor (201), a step hole (206) is formed in the tail end of the central hole (205), the bushing (203) is installed in the step hole (206), the insulating support sleeve (204) is coaxially arranged in the bushing (203), the inner conductor (202) is installed in a middle hole of the insulating support sleeve (204), and the outer end of the inner conductor (202) is connected with a connecting countersunk hole (104) in a matched mode.

2. The post-fed millimeter wave waveguide coaxial converter according to claim 1, wherein the height of the ridge waveguide impedance matching section (103) gradually decreases in a stepwise manner from the closed end of the waveguide body (1) to the other end, the length of each step is 1/3λ to 1/4λ, and the thickness of each step is 0.04 λ to 0.1λ.

3. The feed-back millimeter wave waveguide coaxial converter according to claim 1, characterized in that the waveguide body (1) is further provided with a joint inner cavity (207) communicating with the central hole (205).

4. The feed-back millimeter wave waveguide coaxial converter according to claim 1, wherein a connecting flange (105) is arranged at the bottom of the waveguide body (1), and a plurality of threaded holes (106) are symmetrically arranged on the connecting flange (105).

5. The feed-back millimeter wave waveguide coaxial converter according to claim 1, wherein one end of the inner conductor (202) is provided with a slot insertion hole (208), and the other end of the inner conductor (202) is provided with a slot insertion plug (209).

6. The feed-back millimeter wave waveguide coaxial converter according to claim 1, wherein the terminal flange of the outer conductor (201) forms a land (210), and a plurality of mounting screws (211) are provided on the land (210).

7. The post-fed millimeter wave waveguide coaxial converter of claim 1, wherein a plurality of side holes (212) are symmetrically provided on the insulating support sleeve (204), the side holes (212) being used for adding air medium.