阅读说明：本技术 一种工作于x波段的圆波导te11-tm01混合模式激励器及设计方法 (Circular waveguide TE11-TM01 hybrid mode exciter working in X wave band and design method ) 是由 任杰 翁明 李永东 曹猛 林舒 于 2021-08-27 设计创作，主要内容包括：本发明公开了一种工作于X波段的圆波导TE11-TM01混合模式激励器及设计方法,属微波模式激励器领域,旨在解决激励器仅为单模式激励器,且其结构不能调整的问题。本发明提出的混合模式激励器通过矩形波导传输段与矩形波导截至段形成一种模式,再结合圆波导结构形成混合模式,矩形波截止段减小矩形波导传输段输入端反射,使其具有低反射优点,再对圆波导结构上设置阻抗匹配段来实现阻抗匹配。在普通的带有矩形槽结构的模式转换器结构基础上,增加矩形槽结构的调节模块,可用于调节输出模式的模式混合比。本发明提出的混合模式激励器结构简单,易于加工,在进行实验时便于组装测试,为高功率微波测量系统中的混合模式研究提供了技术基础。(The invention discloses a circular waveguide TE11-TM01 mixed mode exciter working in an X wave band and a design method thereof, belongs to the field of microwave mode exciters, and aims to solve the problems that the exciter is only a single mode exciter, and the structure of the exciter cannot be adjusted. The mixed mode exciter forms a mode through the rectangular waveguide transmission section and the rectangular waveguide cut-off section, then forms a mixed mode by combining with the circular waveguide structure, reduces the reflection of the input end of the rectangular waveguide transmission section through the rectangular waveguide cut-off section, so that the mixed mode exciter has the advantage of low reflection, and then realizes impedance matching by arranging the impedance matching section on the circular waveguide structure. On the basis of a common mode converter structure with a rectangular groove structure, an adjusting module with the rectangular groove structure is added, and the mode mixing ratio of an output mode can be adjusted. The mixed mode exciter provided by the invention has the advantages of simple structure, easiness in processing, convenience in assembly and test during experiment, and provides a technical basis for mixed mode research in a high-power microwave measurement system.)

1. A circular waveguide TE11-TM01 mixed mode exciter working in an X wave band is characterized by comprising a rectangular waveguide transmission section (1), a rectangular groove structure (2), a rectangular waveguide cut-off section (3), a circular waveguide structure (4) and an impedance matching section (5);

the rectangular waveguide transmission section (1) and the rectangular waveguide cut-off section (3) are symmetrically arranged at two ends of the rectangular groove structure (2), the circular waveguide structure (4) is arranged at the center above the rectangular groove structure (2), and the impedance matching section (5) is arranged above the circular waveguide structure (4).

2. The circular waveguide TE11-TM01 hybrid mode exciter of claim 1, wherein the length of the rectangular waveguide transmission section (1) is greater than the length of the rectangular waveguide cutoff section (3).

3. Circular waveguide TE11-TM01 hybrid mode exciter operating in the X-band in accordance with claim 2, characterized by that the rectangular waveguide transmission section (1) is open-ended for microwave input.

4. The circular waveguide TE11-TM01 hybrid mode exciter of claim 2, wherein the rectangular waveguide cutoff section (3) is port-closed for cutting off microwaves.

5. The circular waveguide TE11-TM01 hybrid mode exciter of claim 1, wherein the axis of the circular waveguide structure (4) coincides with the axis of the impedance matching section (5).

6. The circular waveguide TE11-TM01 hybrid mode exciter of claim 1, wherein the impedance matching section (5) is formed by a 3-stage stepped circular waveguide.

7. Circular waveguide TE11-TM01 hybrid mode exciter operating in the X-band in accordance with claim 1, characterized by the rectangular slot structure (2) being height adjustable as required.

8. The design method of the circular waveguide TE11-TM01 hybrid mode exciter working in the X-band according to any one of claims 1 to 7 is adopted, and the design method is characterized by comprising the following steps:

s1, sending the microwave into the rectangular waveguide transmission section (1);

s2, transmitting microwaves into the rectangular groove structure (2) through the rectangular waveguide transmission section (1), converting the microwaves into a target mode through the rectangular groove structure (2), and transmitting the target mode into the circular waveguide structure (4);

and S3, outputting the target mode after the impedance matching is realized through the impedance matching section (5).

9. The design method of circular waveguide TE11-TM01 hybrid mode exciter working in X band as claimed in claim 8, characterized in that rectangular waveguide cut-off section (3) is used to reduce the input end reflection of rectangular waveguide transmission section (1).

Technical Field

The invention belongs to the field of microwave mode exciters, and relates to a circular waveguide TE11-TM01 hybrid mode exciter working in an X wave band and a design method thereof.

Background

In the current high-power microwave online measurement system, real mode mixing information cannot be obtained in an actual high-power experiment, so that whether a method for judging the mode purity is accurate cannot be verified, different mode mixing conditions need to be calibrated under the low-power condition, and a basis is provided for verification of a mixed mode diagnosis method.

Mode conversion is very important for transmission and transmission of high-power microwaves, and the high-power microwaves often need different forms of waveguides for mode conversion in order to control the mode during transmission. However, the actuators reported at present are mainly single-mode actuators, and have a fixed structure and cannot be adjusted.

Disclosure of Invention

In order to overcome the drawbacks of the prior art, the present invention provides a circular waveguide TE11-TM01 hybrid mode exciter operating in the X-band and a design method thereof, and aims to solve the technical problems that the exciter is only a single mode exciter and the structure of the exciter cannot be adjusted in the prior art.

In order to achieve the purpose, the invention adopts the following technical scheme to realize the purpose:

the invention provides a circular waveguide TE11 and TM01 mixed mode exciter working in an X wave band, which comprises a rectangular waveguide transmission section, a rectangular groove structure, a rectangular waveguide cut-off section, a circular waveguide structure and an impedance matching section;

the rectangular waveguide transmission section and the rectangular waveguide cut-off section are symmetrically arranged at two ends of the rectangular groove structure, the circular waveguide structure is arranged at the center above the rectangular groove structure, and the impedance matching section is arranged above the circular waveguide structure.

Preferably, the length of the rectangular waveguide transmission section is greater than the length of the rectangular waveguide cutoff section.

Preferably, the rectangular waveguide transmission section port is open for inputting microwaves.

Preferably, the rectangular waveguide cutoff section is closed at the port for cutting off the microwave.

Preferably, the axis of the circular waveguide structure coincides with the axis of the impedance matching section.

Preferably, the impedance matching section is formed of a 3-stage stepped circular waveguide.

Preferably, the rectangular groove structure can be adjusted in height as required.

The invention also provides a design method of the circular waveguide TE11-TM01 mixed mode exciter working in the X wave band, which comprises the following steps:

s1, sending the microwave into the rectangular waveguide transmission section;

s2, transmitting microwaves into the rectangular groove structure through the rectangular waveguide transmission section, converting the microwaves into a target mode through the rectangular groove structure, and transmitting the target mode into the circular waveguide structure;

and S3, outputting the target mode after realizing impedance matching through the impedance matching section.

Preferably, the rectangular waveguide cut-off is used to reduce input end reflections of the rectangular waveguide transmission segment.

Compared with the prior art, the invention has the following beneficial effects:

according to the circular waveguide TE11-TM01 mixed mode exciter working in the X wave band, the rectangular waveguide transmission section and the rectangular waveguide cut-to section are arranged on the two sides of the rectangular groove structure, when microwaves enter the rectangular waveguide transmission section, the rectangular waveguide cut-to section reduces the reflection of the input end of the rectangular waveguide transmission section, so that the exciter has the advantages of low reflection and low loss, the circular waveguide structures are arranged on the rectangular waveguide transmission section and the rectangular waveguide cut-to section to achieve the advantage of multiple modes, and the impedance matching section is arranged on the circular waveguide structure to achieve impedance matching; the circular waveguide structure is arranged at the center above the rectangular groove structure, the rectangular groove structure adjusts the microwave, the microwave is in a symmetrical mode when being transmitted to the circular waveguide structure, the circular waveguide structure is not arranged at the center of the rectangular groove structure, other interference modes can be generated, and the effect of the microwave; the rectangular slot structure is added to tune the performance of the actuator. The mixed mode exciter provided by the invention has the advantages of simple structure, easiness in processing, convenience in assembly and test during experiment, and provides a technical basis for mixed mode research in a high-power microwave measurement system.

Further, the length of the rectangular waveguide transmission section is greater than that of the rectangular waveguide cut-off section, so as to improve the transmission efficiency of the microwave and reduce reflection.

Furthermore, the axis of the circular waveguide structure coincides with the axis of the impedance matching section, so that the transmission speed of the microwave in the exciter can be increased, and the microwave transmission efficiency can be reduced if the circular waveguide structure and the impedance matching section are arranged in different axes.

Furthermore, on the basis of a common mode converter structure with a rectangular groove structure, a rectangular groove adjusting block is added, and the rectangular groove adjusting block can be used for adjusting the mode mixing ratio of the output mode.

Further, the port of the transmission section of the rectangular waveguide is open and can be used for inputting microwaves, and the port of the cut-off section of the rectangular waveguide is closed and can be used for cutting off the microwaves.

Further, according to the chebyshev impedance transformation section principle, the impedance matching section adopts a three-order chebyshev impedance transformation section.

The design method of the circular waveguide TE11-TM01 mixed mode exciter working in the X wave band provided by the invention has the advantages of simple operation steps, convenience in realization and better application prospect in the field of microwave mode exciters.

Drawings

FIG. 1 is a schematic structural diagram of a fundamental mode converter in a circular waveguide TE11 and TM01 hybrid mode exciter according to the present invention;

FIG. 2 is a rear view of FIG. 1;

FIG. 3 is a left side view of FIG. 1;

FIG. 4 is a schematic structural view of a rectangular slot adjusting block of the present invention;

FIG. 5 is a diagram of the S11 parameters of the TE10 mode of the rectangular waveguide of the present invention (the height of the rectangular slot is adjusted to 1 mm);

FIG. 6 is a diagram of S21 parameters of TE11 mode of circular waveguide (the height of rectangular slot is adjusted to 1 mm);

FIG. 7 is a diagram of the S11 parameters of the TE10 mode of the rectangular waveguide of the present invention (the height of the rectangular slot is adjusted to 12.6 mm);

FIG. 8 is a diagram of the S21 parameters of the TE11 mode of the circular waveguide of the present invention (the height of the rectangular slot is adjusted to 12.6 mm);

FIG. 9 is a diagram of the S11 parameters of the TE10 mode of the rectangular waveguide of the present invention (the rectangular slot is adjusted to have a height of 11 mm);

FIG. 10 is a diagram of the S21 parameters of the TE11 mode of the circular waveguide of the present invention (the height of the rectangular slot is adjusted to 11 mm).

Wherein: 1-a rectangular waveguide transmission section; 2-a rectangular groove structure; 3-rectangular waveguide cut-off section; 4-circular waveguide structure; 5-impedance matching section.

Detailed Description

In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the invention described herein are capable of operation in sequences other than those illustrated or described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

The invention is described in further detail below with reference to the accompanying drawings:

the invention discloses a circular waveguide TE11-TM01 mixed mode exciter working in an X wave band, which comprises a basic mode converter structure and a rectangular groove adjusting block structure.

As shown in fig. 1, 2 and 3, the fundamental mode converter structure is composed of the following parts in the microwave transmission direction, respectively: the device comprises a rectangular waveguide transmission section 1, a rectangular groove structure 2, a rectangular waveguide cut-off section 3, a circular waveguide structure 4 and an impedance matching section 5.

Preferably, the rectangular waveguide transmission section 1 and the rectangular waveguide cut-off section 3 are symmetrically arranged at two ends of the rectangular groove structure 2, the circular waveguide structure 4 is arranged at the center position above the rectangular groove structure 2, the rectangular groove structure 2 adjusts microwaves, the microwaves are transmitted to the circular waveguide structure 4 in a symmetrical mode, if the circular waveguide structure 4 is not arranged at the center of the rectangular groove structure, other interference modes can be generated to influence the effect of the invention, and the impedance matching section 5 is arranged above the circular waveguide structure 4 to realize impedance matching; the length of the rectangular waveguide transmission section 1 is greater than that of the rectangular waveguide cut-off section 3, so that the transmission efficiency of the microwave is improved, and the reflection is reduced; specifically, when the rectangular groove structure 2 is not provided, the rectangular waveguide transmission section 1 and the rectangular waveguide cut-off section 3 are integrated, and the rectangular groove structure 2 is added to divide the rectangular waveguide into the rectangular waveguide transmission section 1 and the rectangular waveguide cut-off section 3 in order to adjust the performance of the hybrid mode exciter. The impedance matching section 5 is formed by 3 stages of stepped circular waveguides, specifically: according to the Chebyshev impedance transformation section principle, the impedance matching section adopts a three-order Chebyshev impedance transformation section; the axis of the circular waveguide structure 4 is overlapped with the axis of the impedance matching section 5, so that the transmission speed of the microwave in the exciter can be increased, and the microwave transmission efficiency can be reduced if the circular waveguide structure and the impedance matching section are arranged in different axes.

Preferably, the rectangular waveguide transmission section 1 is open at the port for inputting microwaves; the rectangular waveguide cut-off section 3 is closed in port and used for cutting off microwaves.

The invention provides a design method of a circular waveguide TE11-TM01 mixed mode exciter working in an X wave band, which comprises the following steps:

s1, the microwave enters the rectangular waveguide transmission section 1;

s2, the rectangular waveguide transmission section 1 transmits microwaves into the rectangular groove structure 2, the microwaves are converted into a target mode through the rectangular groove structure 2, and the target mode is transmitted into the circular waveguide structure 4;

the excitation condition of the microwave is different due to the different sizes of the rectangular groove structures 2, only a TM01 mode and a small amount of TE11 modes can be transmitted under specific length and width, and the mode mixing ratio can be adjusted due to the different heights.

And S3, finally, outputting the target mode after the impedance matching is realized through the impedance matching section 5.

Preferably, the rectangular waveguide cutoff section 3 is used to reduce the input end reflection of the rectangular waveguide transmission section 1.

As shown in fig. 4, the adjusting block structure of the rectangular groove structure 2 with reference to fig. 4(a), 4(b), 4(c) and 4(d) can be adjusted according to the height requirement of the rectangular groove structure 2: the rectangular waveguide transmission section 1 in the fundamental mode converter structure is of a fixed size, the height is a fixed value, the rectangular groove structure 2 has an initial height, and when the height of the rectangular groove structure 2 needs to be adjusted, a corresponding adjusting block as shown in fig. 4 is added.

In this embodiment, each portion is made of metal. Referring to fig. 1, the input end face of the rectangular waveguide transmission section 1 has a length of 22.86mm, a width of 10.16mm, and a length of 45.7mm in the microwave input direction; the length of the parallel surface of the rectangular waveguide cut-off section 3 and the input end surface is 22.86mm, the width is 10.16mm, and the length along the microwave input direction is 24.45 mm; the initial dimensions of the rectangular slot structure 2 were 12.8mm in length perpendicular to the microwave input direction, 33mm in width and 10.6mm in length along the microwave input direction.

The diameter of the circular waveguide structure 4 is 29.2mm, and the height is 76.84 mm; the impedance matching section 4 is composed of 3 stages of stepped circular waveguides, from bottom to top, the diameter of the first section is 36.14mm, and the height is 5.94 mm; the diameter of the second section is 44.94mm, and the height is 6.5 mm; the third section had a diameter of 49.5mm and a height of 25.53 mm.

After modeling and simulation processing are performed on the height-adjustable mixed mode actuator structure of the rectangular groove structure 2 by using the adjusting block of the rectangular groove structure 2, the following conditions are analyzed respectively:

when the height of the rectangular groove structure 2 is 12.8mm, S11 parameters of a TE10 mode of the rectangular waveguide are shown in FIG. 5, S21 parameters of a TE11 mode of the circular waveguide and a TM01 mode are shown in FIG. 6, the S11 parameters are less than-15 dB in a 9.2-10.2 GHz frequency band, S21 parameters of a TE11 mode at a frequency point of 9.7GHz are-21.59 dB, namely the TE11 mode content is 0.69%;

when the height of the rectangular groove structure 2 is 1mm, S11 parameters of a TE10 mode of the rectangular waveguide are shown in FIG. 7, S21 parameters of a TE11 mode of the circular waveguide and a TM01 mode are shown in FIG. 8, the S21 parameters are less than-15 dB in a 9.6-10.2 GHz frequency band, S21 parameters of a TE11 mode at a frequency point of 9.7GHz are-6.41 dB, namely the TE11 mode content is 22.86%;

when the height of the rectangular groove structure 2 is 11mm, S11 parameters of a rectangular waveguide TE10 mode are shown in FIG. 9, S21 parameters of a round waveguide TE11 mode and a TM01 mode are shown in FIG. 10, the S21 parameters are less than-15 dB in a 9.2-9.9 GHz frequency band, S21 parameters of a TE11 mode at a 9.7GHz frequency point are-9.68 dB, and the TE11 mode content is 10.76%.

For other mixed-mode outputs with TE11 content of 0.69-22.86%, the height of the rectangular groove structure 2 can be adjusted by changing the adjusting block of the rectangular groove structure 2, and the specific corresponding relationship is as follows:

TABLE 1 relationship of rectangular groove height to TE11 content

TE11 content/%)	Height/mm of rectangular groove
		0.69	12.8
2.15	12.4
		4.28	12
7.46	11.5
		10.76	11
15.81	10
		17.78	8
19.59	6
		21.23	4
22.86	1

In summary, the circular waveguide TE11-TM01 hybrid mode exciter working in the X-band provided by the invention has good transmission performance and high conversion efficiency, and has the advantages of low reflection, adjustable mode mixing ratio and the like, and is simple to process, the TE11 content can be adjusted according to table 1, and the hybrid mode output of the circular waveguide TE11 and the TM01 is provided.

The above-mentioned contents are only for illustrating the technical idea of the present invention, and the protection scope of the present invention is not limited thereby, and any modification made on the basis of the technical idea of the present invention falls within the protection scope of the claims of the present invention.