阅读说明：本技术 实现毫米波频段微带同轴转换的装置 (Device for realizing millimeter wave frequency band microstrip coaxial conversion ) 是由 黄蔚 苏阳 于 2020-12-22 设计创作，主要内容包括：本发明涉及一种实现毫米波频段微带同轴转换的装置,包括绝缘子、微带线、屏蔽盒和空气柱结构,所述的空气柱结构在微带线与同轴之间,同样在绝缘子与屏蔽盒的烧结处,绝缘子焊接在微带线的金属带上,空气柱结构为圆柱体,空气柱结构包括两个不同半径的圆柱体或圆台。采用了本发明的实现毫米波频段微带同轴转换的装置,适用于67GHz以下频段的绝缘子与微带线的转换结构,通过改变屏蔽盒之间的空气柱的形状,即改变屏蔽盒的结构,改善了屏蔽盒中毫米波频段驻波。(The invention relates to a device for realizing millimeter wave frequency band microstrip coaxial conversion, which comprises an insulator, a microstrip line, a shielding box and an air column structure, wherein the air column structure is arranged between the microstrip line and the coaxial line and is welded on a metal strip of the microstrip line at a sintering position of the insulator and the shielding box, the air column structure is a cylinder, and the air column structure comprises two cylinders or round tables with different radiuses. The device for realizing the coaxial conversion of the millimeter wave frequency band microstrip is suitable for the conversion structure of the insulator and the microstrip line in the frequency band below 67GHz, and improves the standing wave of the millimeter wave frequency band in the shielding box by changing the shape of the air column between the shielding boxes, namely changing the structure of the shielding boxes.)

1. The device for realizing millimeter wave frequency band microstrip coaxial conversion is characterized by comprising an insulator, a microstrip line, a shielding box and an air column structure, wherein the air column structure is arranged between the microstrip line and a coaxial line, the insulator is welded on a metal strip of the microstrip line at a sintering position of the insulator and the shielding box, and the air column structure is used for improving insertion loss and standing wave.

2. The device for realizing microstrip coaxial conversion of millimeter wave frequency band according to claim 1, wherein the air column structure is a cylinder, and the length h is not more than 6 mm.

3. The device according to claim 1, wherein the air column structure comprises two air columns with different radiiThe total length of the air column structure is h, and the radiuses of the two cylinders are r respectively₁And r₂Near the radius r of the insulator₁Greater than radius r near the microstrip line₂Length of h₁And h₂And h is h₁And h₂And (4) summing.

4. The device for realizing microstrip coaxial conversion of a millimeter wave frequency band according to claim 1, wherein the air column structure comprises two truncated cones with different radii, the total length of the air column structure is h, and the radius of the truncated cone close to the insulator in the two truncated cones is r₁The radius of the circular truncated cone close to the microstrip line is r₂Near the radius r of the insulator₁Greater than radius r near the microstrip line₂。

5. The device for realizing microstrip coaxial conversion of a millimeter wave frequency band according to claim 1, wherein the shape of the air column structure is adjusted according to actual processing errors.

6. The apparatus of claim 1, wherein the apparatus is configured to perform microstrip coaxial conversion in a millimeter wave band below 67 GHz.

7. The device for realizing microstrip coaxial conversion of millimeter wave frequency band according to claim 3 or 4, wherein the length h of the device is not more than 0.6 mm.

Technical Field

The invention relates to the field of microwave radio frequency, in particular to the field of microstrip shielding box structure technology, and specifically relates to a device for realizing microstrip coaxial conversion in a millimeter wave frequency band.

Background

The design work of the circuit is only the first step of the work, and the problems of structure and process must be considered seriously to really apply the microstrip circuit to the practice.

In the design of the millimeter wave circuit, a microstrip line circuit is adopted in a frequency band below 67GHz, and a shielding box is required to be added in the design circuit. The shielding box mainly plays a role of electric shielding in a circuit, and simultaneously can protect the machinery and the environment. The shielding box is generally composed of a main body, a bottom plate and a cover plate. The mechanical firmness and reliability of the shielding box are enhanced, and the circuit board and the shielding box bottom plate are sintered together. When the size of the shield can is not appropriate, a resonance effect occurs. Meanwhile, the insulator of the adapter and the microstrip conductor strip are firmly welded to ensure reliable contact.

The microstrip line and the coaxial line are two common transmission lines in a microwave system, the common interconnection mode of the two transmission lines in a low frequency band is direct welding, the coaxial inner conductor is welded on a metal strip line of the microstrip line, the outer conductor is installed on a ground plane of the microstrip line, as shown in fig. 1, the figure is a traditional structure mode, at the moment, the test result is shown in fig. 2, the frequency band below 67GHz, and the standing wave ratio of a part of the frequency band is higher than 1.3.

In the millimeter wave frequency band, the connection mode can cause the loss of millimeter wave signals to be increased and influence standing waves. The standing-wave ratio can be influenced by the conversion structure of the insulator and the microstrip. From circuit theory analysis, the microstrip coaxial conversion structure is equivalent to a parallel capacitor between a coaxial line and a microstrip line. At low frequencies, the capacitance is small and can be considered as an open circuit, but as the frequency increases, part of the transmitted signal begins to reflect, resulting in a significant increase in both standing waves and insertion loss of the switching structure.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides the device for realizing the microstrip coaxial conversion of the millimeter wave frequency band, which has the advantages of low consumption, simple structure and wider application range.

In order to achieve the above purpose, the device for realizing microstrip coaxial conversion of millimeter wave frequency band of the invention is as follows:

the device for realizing millimeter wave frequency band microstrip coaxial conversion is mainly characterized by comprising an insulator, a microstrip line, a shielding box and an air column structure, wherein the air column structure is arranged between the microstrip line and the coaxial line, the insulator is welded on a metal strip of the microstrip line at a sintering position of the insulator and the shielding box, and the air column structure is used for improving insertion loss and standing wave.

Preferably, the air column structure is a cylinder, and the length h is not more than 6 mm.

Preferably, the air column structure comprises two cylinders with different radii, the total length of the air column structure is h, and the radii of the two cylinders are r₁And r₂Near the radius r of the insulator₁Greater than radius r near the microstrip line₂Length of h₁And h₂And h is h₁And h₂And (4) summing.

Preferably, the air column structure comprises two circular truncated cones with different radiuses, the total length of the air column structure is h, and the radius of the circular truncated cone close to the insulator in the two circular truncated cones is r₁The radius of the circular truncated cone close to the microstrip line is r₂Near the radius r of the insulator₁Greater than radius r near the microstrip line₂。

Preferably, the shape of the air column structure is adjusted according to actual machining errors.

Preferably, the frequency band targeted by the device is below 67 GHz.

Preferably, the length h of the device is not more than 0.6 mm.

The device for realizing the coaxial conversion of the millimeter wave frequency band microstrip is suitable for the conversion structure of the insulator and the microstrip line in the frequency band below 67GHz, and improves the standing wave of the millimeter wave frequency band in the shielding box by changing the shape of the air column between the shielding boxes, namely changing the structure of the shielding boxes.

Drawings

Fig. 1 is a schematic diagram of a microstrip coaxial switching structure in the prior art.

Fig. 2 is a schematic diagram of a simulation result of a microstrip coaxial conversion structure in the prior art.

Fig. 3 is a schematic diagram of a microstrip coaxial conversion structure of an air column of the device for realizing microstrip coaxial conversion of the millimeter wave frequency band.

Fig. 4 is a schematic diagram of a simulation result of a microstrip coaxial conversion structure of an air column of the device for realizing microstrip coaxial conversion of the millimeter wave frequency band.

Fig. 5 is a schematic diagram of a microstrip coaxial conversion structure of a device for realizing microstrip coaxial conversion of a millimeter wave frequency band and a double-section cylindrical air column.

Fig. 6 is a schematic diagram of a simulation result of a microstrip coaxial conversion structure of a device for realizing microstrip coaxial conversion of a millimeter wave frequency band and a double-section cylindrical air column.

Fig. 7 is a schematic diagram of a microstrip coaxial conversion structure of a truncated cone-shaped air column of the device for realizing microstrip coaxial conversion of the millimeter wave frequency band according to the present invention.

Fig. 8 is a schematic diagram of a simulation result of a microstrip-coaxial conversion structure of a truncated cone-shaped air column of the device for realizing microstrip-coaxial conversion of a millimeter wave frequency band according to the present invention.

Detailed Description

In order to more clearly describe the technical contents of the present invention, the following further description is given in conjunction with specific embodiments.

The device for realizing millimeter wave frequency band microstrip coaxial conversion comprises an insulator, a microstrip line, a shielding box and an air column structure, wherein the air column structure is arranged between the microstrip line and the coaxial line, the insulator is welded on a metal strip of the microstrip line at a sintering position of the insulator and the shielding box, and the air column structure is used for improving insertion loss and standing wave.

As a preferred embodiment of the invention, the air column structure is a cylinder, and the length h is not more than 6 mm.

As a preferred embodiment of the present invention, the air column structure comprises two cylinders with different radii, the total length of the air column structure is h, and the radii of the two cylinders are r₁And r₂Near the radius r of the insulator₁Greater than radius r near the microstrip line₂Length of h₁And h₂And h is h₁And h₂And (4) summing.

In a preferred embodiment of the present invention, the air column structure comprises two circular truncated cones with different radii, the total length of the air column structure is h, and one of the two circular truncated cones is close toThe radius of the round platform of the near insulator is r₁The radius of the circular truncated cone close to the microstrip line is r₂Near the radius r of the insulator₁Greater than radius r near the microstrip line₂。

In a preferred embodiment of the present invention, the shape of the air column structure is adjusted in accordance with an actual machining error.

In a preferred embodiment of the present invention, the frequency band of the device is 67GHz or less.

As a preferred embodiment of the invention, the length h of the device does not exceed 0.6 mm.

In the specific implementation mode of the invention, a millimeter wave frequency band microstrip coaxial conversion structure is designed, and an air column structure is added between a microstrip line and a coaxial line in the conversion structure, namely, after a section of air column is left at the sintering position of an insulator and a shielding box, the insulator is welded on a metal strip of the microstrip line, as shown in fig. 3. The frequency band of the invention is below 67GHz, and the connector joint is 1.85 mm. In this case, as shown in fig. 4, the standing wave ratios in the frequency bands of 67GHz or less are all 1.5 or less.

A section of air column is added on the microstrip coaxial conversion interface, which mainly embodies that:

1. and the capacitance value of the parallel capacitor of the microstrip coaxial conversion structure is reduced.

2. And a section of inductive air cut-off coaxial line is added in the conversion structure to tune the parallel capacitor, so that the standing wave and the insertion loss of the conversion structure are improved.

The air column structure of the present invention is used to improve insertion loss and improve standing waves.

The invention adopts the following technical scheme for solving the technical problems:

the design of the present invention is shown in fig. 5. The total length of the air column is h, and the air column is divided into two cylinders with different radiuses, namely radius r₁，r₂Length of air column h₁,h₂And h ═ h₁+h₂. The test results at this time are shown in fig. 6.

However, the present invention is in processingIn the process, due to h₁,h₂The value of (a) is relatively small, and there is a machining error, which affects the actual result, so that fig. 7 is a diagram in which the shape of the air column is partially modified according to the actual machining difficulty. The air column in fig. 7 is changed from a cylinder into a circular truncated cone, the length of the circular truncated cone is h, and the radius of the air column close to the insulator glass is r₁The radius near the microstrip line connection part is r₂. The test results are shown in fig. 8.

The invention adds a section of inductive air column in the conversion structure and adjusts the shape of the air column according to the actual processing error. The capacitance value of the parallel capacitor of the microstrip coaxial conversion structure is reduced through the air column, the parallel capacitor is tuned, and then the standing wave of the conversion structure is improved.

The technical scheme of the invention is further explained in detail by combining the attached drawings:

the invention improves standing waves by changing the shape of the air column. The invention comprehensively considers the error and difficulty in the actual processing process, and optimizes the shape of the air column on the basis, thereby realizing better effect.

The design of the present invention is shown in fig. 5. The difference from FIG. 3 is that the air column in FIG. 3 is formed by cutting a shielding box with a radius r₁The length of the cylinder is h, and the h is less than or equal to 6mm according to the requirement of the assembly process. In FIG. 5, the cylinder is cut, but the air column h with the same length is divided into two cylinders with different radii, namely, radius r₁，r₂Length of air column h₁,h₂And h ═ h₁+h₂. The test results at this time are shown in fig. 6. Comparing fig. 6 and fig. 4, the overall standing wave ratio is improved.

However, in the process of the invention, h is used as a result₁,h₂The value of (a) is relatively small, and there is a machining error, which affects the actual result, so that fig. 7 is a diagram in which the shape of the air column is partially modified according to the actual machining difficulty. The difference from fig. 3 and 5 is that the air column in fig. 7 is changed from a cylinder into a circular truncated cone, and the length of the circular truncated cone is h and depends onThe radius of the near-insulator glass air column is r₁The radius near the microstrip line connection part is r₂. The test results are shown in fig. 8. Comparing fig. 6 and fig. 8, the results are basically similar, with fig. 8 being slightly better than those in fig. 6.

The invention adds a section of inductive air column in the conversion structure and adjusts the shape of the air column according to the actual processing error. The capacitance value of the parallel capacitor of the microstrip coaxial conversion structure is reduced through the air column, the parallel capacitor is tuned, and then the standing wave of the conversion structure is improved.

The device for realizing the coaxial conversion of the millimeter wave frequency band microstrip is suitable for the conversion structure of the insulator and the microstrip line in the frequency band below 67GHz, and improves the standing wave of the millimeter wave frequency band in the shielding box by changing the shape of the air column between the shielding boxes, namely changing the structure of the shielding boxes.

In this specification, the invention has been described with reference to specific embodiments thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of the invention. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.