阅读说明：本技术 一种应用于介质加载回旋行波管中的角向功分波导结构 (Angular power division waveguide structure applied to medium-loaded gyrotron traveling wave tube ) 是由 徐勇 郑智斌 毛娅 刘智航 田辰彦 王高磊 于 2020-12-16 设计创作，主要内容包括：本发明公开了一种应用于介质加载回旋行波管中的角向功分波导结构,涉及微波、毫米波电真空器件技术领域。本发明的角向功分波导结构设置于介质加载互作用段和输出波导段之间；角向功分波导结构包括：圆波导、N个正向角向功分波导、N个逆向角向功分波导；正向角向功分波导为沿圆波导外壁角向均匀分布的斜出式矩形波导,逆向角向功分波导为沿圆波导外壁角向均匀分布的斜入式矩形波导。回旋行波管在预群聚阶段产生的电磁波在进入角向功分波导结构后,绝大部分电磁波能量直接传播到角向功分波导中,进而被吸波结构吸收；角向功分波导结构增加了耗散面积,提高了回旋行波管平均功率容量,并且角向功分波导结构还有效缩短了介质加载段的长度。(The invention discloses an angular power division waveguide structure applied to a medium-loaded gyrotron traveling wave tube, and relates to the technical field of microwave and millimeter wave electro-vacuum devices. The angular power division waveguide structure is arranged between a medium loading interaction section and an output waveguide section; the angular power division waveguide structure comprises: the waveguide comprises a circular waveguide, N forward angular power distribution waveguides and N reverse angular power distribution waveguides; the forward angular power distribution waveguide is an oblique rectangular waveguide which is evenly distributed along the outer wall of the circular waveguide in an angular mode, and the reverse angular power distribution waveguide is an oblique rectangular waveguide which is evenly distributed along the outer wall of the circular waveguide in an angular mode. After electromagnetic waves generated by the gyrotron traveling wave tube in the pre-clustering stage enter the angular power division waveguide structure, most of electromagnetic wave energy is directly transmitted to the angular power division waveguide and is further absorbed by the wave absorbing structure; the angular power division waveguide structure increases the dissipation area, improves the average power capacity of the gyrotron traveling wave tube, and effectively shortens the length of the medium loading section.)

1. The utility model provides an angular power distribution waveguide structure for among gyrotron travelling wave tube high frequency interaction system, sets up between medium loading interaction section and the output waveguide section of medium loading gyrotron travelling wave tube, its characterized in that, angular power distribution waveguide structure includes: the waveguide comprises a circular waveguide, N forward angular power distribution waveguides and N reverse angular power distribution waveguides; the forward angular power distribution waveguide is an oblique-out rectangular waveguide which is evenly distributed along the outer wall of the circular waveguide in an angular direction, the reverse angular power distribution waveguide is an oblique-in rectangular waveguide which is evenly distributed along the outer wall of the circular waveguide in an angular direction, and the included angle between the oblique-out rectangular waveguide and the circular waveguide is theta₁The included angle between the oblique rectangular waveguide and the circular waveguide is theta₂And theta₁+θ₂＝180°，20°≤θ₁≤40°。

2. The structure of claim 1, wherein the forward angular power division waveguides and the backward angular power division waveguides are distributed in a staggered manner, and a terminal of each forward angular power division waveguide is inserted into a middle position of two adjacent backward angular power division waveguides.

3. The structure of claim 2, wherein N is 8, 12, or 16.

4. The structure of the angular power distribution waveguide applied to the high-frequency interaction system of the gyrotron traveling wave tube according to claim 2 or 3, wherein the forward angular power distribution waveguide and the backward angular power distribution waveguide are both internally provided with a wedge-shaped wave absorbing structure made of wave absorbing materials and tightly attached to the wide side of the rectangular waveguide.

5. The structure of claim 2 or 3, wherein the angled power splitting waveguide is a nonstandard rectangular waveguide with the same size as the angled rectangular waveguide.

6. The structure of claim 4, wherein the wave-absorbing material is a ceramic material.

Technical Field

The invention relates to the technical field of microwave and millimeter wave electro-vacuum devices, in particular to an angular power division waveguide structure applied to a medium-loaded gyrotron traveling wave tube.

Background

Gyrotron traveling wave tubes are an important high power millimeter wave source. The high-power broadband high-power electromagnetic wave induction heating device has the characteristics of broadband and high power, and has wide application prospects in the military and civil fields of radar, communication, electronic countermeasure, material treatment, controlled thermonuclear fusion plasma heating, environmental protection and the like, so that the high-power broadband high-power electromagnetic wave induction heating device is highly valued internationally and domestically.

Through development for many years, various tube-type structures have been derived from the gyrotron traveling wave tube, wherein the gyrotron traveling wave tube with a medium loading structure is a very successful gyrotron traveling wave tube structure, and the gyrotron traveling wave tube comprises an input waveguide, a medium loading interaction section and an output waveguide which are sequentially connected. The high-frequency interaction system is a core component of the gyrotron traveling wave tube, and the performance of the high-frequency interaction system influences performance indexes such as working bandwidth, efficiency, gain and power capacity of the gyrotron traveling wave tube. In the conventional medium-loaded gyrotron traveling wave tube, due to reflection of an output system of the conventional medium-loaded gyrotron traveling wave tube, excessive high-power electromagnetic waves are directly reflected to a medium loading interaction section under the condition of high average power, so that a loss medium at the tail end of the medium loading interaction section is overheated to outgas due to absorption of excessive high-power electromagnetic wave energy, and stable operation of the gyrotron traveling wave tube is further influenced. Furthermore, in the dielectric loading section of the high frequency interaction system, the electromagnetic energy density distribution increases non-linearly and exponentially with the deepening of electron beam-wave interaction in the axial direction of the high frequency system, and particularly in the vicinity of the output end of the dielectric loading section, the electromagnetic energy density is highest, and the high density electromagnetic energy distribution necessarily causes absorption by the high density electromagnetic energy medium. Under the condition of high average power, the output end loss medium of the medium loading interaction section is overheated to give vent to air due to the fact that the medium absorbs excessive high-power electromagnetic wave energy, the stability of the gyrotron traveling wave tube is further affected, and the average power capacity of a high-frequency interaction system is limited. In addition, due to the reflection of the output system, a part of the output electromagnetic energy is also caused to return directly into the dielectric loading section and concentrated to be dissipated at the end ceramic ring. This also causes the end-loss media to overheat and outgas by absorbing excess high power electromagnetic wave energy under high average power conditions, resulting in further limitation of the average power capacity of the high frequency interaction system. Therefore, how to improve the average power capacity of the high-frequency interaction system of the dielectric-loaded gyrotron traveling wave tube is a technical bottleneck problem of the traditional dielectric-loaded gyrotron traveling wave tube.

Disclosure of Invention

The technical bottleneck of high average power output of the traditional medium-loaded gyrotron traveling wave tube is solved. The invention provides an angular power division waveguide structure applied to a high-frequency interaction system of a gyrotron traveling wave tube.

The technical scheme adopted by the invention is as follows:

the utility model provides an angular power distribution waveguide structure for among gyrotron travelling wave tube high frequency interaction system, sets up between medium loading interaction section and the output waveguide section of medium loading gyrotron travelling wave tube, its characterized in that, angular power distribution waveguide structure includes: a circular waveguide, N forward angular power dividing waveguides, and N reverse angular power dividing waveguides, where N is 8, 12, or 16. The forward angular power distribution waveguide is an oblique-out rectangular waveguide which is evenly distributed along the outer wall of the circular waveguide in an angular direction, the reverse angular power distribution waveguide is an oblique-in rectangular waveguide which is evenly distributed along the outer wall of the circular waveguide in an angular direction, and the included angle between the oblique-out rectangular waveguide and the circular waveguide is theta₁(20°≤θ₁Not more than 40 degrees), and the included angle between the inclined rectangular waveguide and the circular waveguide is theta₂And theta₁+θ₂＝180°。

The forward angular power distribution waveguides and the reverse angular power distribution waveguides are distributed in a staggered mode, and the tail end of each forward angular power distribution waveguide is inserted into the middle of two adjacent reverse angular power distribution waveguides.

Oblique-wedge-shaped wave-absorbing structures which are made of wave-absorbing materials and tightly attached to the wide sides of the rectangular waveguides are arranged in the forward angular power distribution waveguide and the reverse angular power distribution waveguide, so that electromagnetic waves transmitted to the non-standard rectangular waveguides are absorbed, and meanwhile, the heat dissipation area of the rectangular waveguides is increased.

Furthermore, the oblique-out rectangular waveguide and the oblique-in rectangular waveguide are nonstandard rectangular waveguides with the same size.

Further, the wave-absorbing material is a ceramic material.

The design principle is as follows:

the angular power division waveguide structure is arranged between the medium loading section and the output smooth section of the medium loading gyrotron traveling wave tube, so that the length of the medium loading section of the traditional medium loading gyrotron traveling wave tube is shortened. After electromagnetic waves generated by the gyrotron traveling wave tube in the pre-clustering stage enter the angular power division waveguide structure, most of electromagnetic wave energy is directly transmitted to the angular power division waveguide, and then is absorbed by the attenuation ceramic chip in the non-standard rectangular waveguide. The dissipation area of the attenuation ceramic wafer of the angular power division waveguide is far larger than that of the ceramic ring of the replaced part, so that the purposes of increasing the dissipation area and improving the average power capacity of the gyrotron traveling wave tube are achieved.

The invention has the following main advantages:

1. most of forward electromagnetic energy generated in the pre-modulation stage of the medium loading interaction section of the gyrotron traveling wave tube can be guided into the forward angular power division waveguide and absorbed by the attenuation medium sheet loaded on the wide side of the non-standard rectangular waveguide. The structure effectively increases the dissipation area of the medium-loaded gyrotron traveling wave tube high-frequency interaction system, and further effectively improves the power capacity of the gyrotron traveling wave tube high-frequency interaction system.

2. Because the plurality of paths of forward angular power division waveguides and reverse angular power division waveguides are loaded at the angular direction of the circular waveguide, the dispersion curve of the working mode of the circular waveguide is far away from the dispersion curve of the working mode of the output smooth waveguide, namely, the dispersion and the electron beam of the working modes of the forward angular power division waveguides and the reverse angular power division waveguides are asynchronous. The electron beams only do drift motion in the forward angular power division waveguide and the reverse angular power division waveguide, further deepen clustering, and prepare for finally forming a good clustering state in an output smooth section and realizing high-efficiency energy conversion. Meanwhile, the electromagnetic power density of the forward angular power division waveguide and the reverse angular power division waveguide is greatly reduced, and the power capacity of the gyrotron traveling wave tube is improved.

3. For the reverse high-power electromagnetic wave reflected by the output system, when the reverse high-power electromagnetic wave passes through the reverse angular power division waveguide, most (accounting for more than 90% of the total energy) of the electromagnetic wave energy also directly propagates into the reverse angular power division waveguide, and then is absorbed by the attenuation ceramic wafer in the non-standard rectangular waveguide. Therefore, the angular power division waveguide structure can also effectively prevent the output electromagnetic wave from directly reflecting to the medium loading section of the gyrotron traveling wave tube, and can effectively realize the isolation of the medium loading section and the output smooth section. The effects of further reducing the dissipation power of the high-frequency system of the gyrotron traveling wave tube and improving the average power capacity of the gyrotron traveling wave tube are achieved.

4. The attenuation ceramic chip loaded in the angular power division waveguide adopts an oblique-wedge-shaped structure and is tightly attached to the wide side of the non-standard rectangular waveguide, so that the contact area of the attenuation ceramic chip and the non-standard rectangular waveguide can be increased as much as possible, and the power capacity of the high-frequency interaction system of the gyrotron traveling wave tube is effectively improved.

Drawings

Fig. 1 is a 3-dimensional diagram of an angular power splitting waveguide structure.

Fig. 2 is a front view and a top view of an angled power division waveguide structure.

Figure 3 is a side view of an angular power dividing waveguide structure.

Fig. 4 is a cross-sectional view of an angular power splitting waveguide structure.

Fig. 5S-parameter of the angular power splitting waveguide structure.

Description of reference numerals: 1. the device comprises a circular waveguide, 2. a forward angular power division waveguide, 3. a reverse angular power division waveguide, 4. an attenuation ceramic chip loaded in the forward angular power division waveguide, and 5. an attenuation ceramic chip loaded in the reverse angular power division waveguide.

Detailed Description

The invention is explained in more detail below with reference to a design example and the attached drawing:

the technical index requirements of the angular power division waveguide structure applied to the medium-loaded gyrotron traveling wave tube are as follows:

circular waveguide mode of operation: TE₀₁Molding; working frequency band: u band (45GHz-52 GHz);

the structure is shown in fig. 1-5. The method comprises the following steps: the device comprises a circular waveguide (1), a forward angular power distribution waveguide (2), a reverse angular power distribution waveguide (3), an attenuation ceramic chip (4) loaded in the forward angular power distribution waveguide, and an attenuation ceramic chip (5) loaded in the reverse angular power distribution waveguide.

Wherein:

circular waveguide (main waveguide) (1): radius 4.04 mm, length dimension 34 mm;

forward angular power dividing waveguide (2): the waveguide comprises 8 paths of oblique-out non-standard rectangular waveguides which are uniformly distributed at the outer wall angle of a circular waveguide. The length dimension a of the forward angular power division waveguide is 19.89 mm, the width dimension b is 5.69 mm, and the narrow dimension is 1.5 mm, wherein theta₁＝38°。

Reverse angular power dividing waveguide (3): the waveguide comprises 8 paths of oblique non-standard rectangular waveguides which are evenly distributed at the outer wall angle of a circular waveguide. The length dimension a of the reverse angular power division waveguide is 19.89 mm, the width dimension b is 5.69 mm, and the narrow dimension is 1.5 mm, wherein theta₂＝142°。

Attenuation ceramic plates (4, 5) loaded in the forward angular power distribution waveguide and the reverse angular power distribution waveguide: the ceramic wafer is respectively loaded at the tail end of the non-standard rectangular waveguide of the forward angular power division waveguide and the tail end of the non-standard rectangular waveguide of the reverse angular power division waveguide, adopts an oblique wedge type gradual change structure and is tightly attached to the wide edge of the non-standard rectangular waveguide. The gradual change length is 16 millimeters, and broadside size 5.69 millimeters, and the most big department of narrow limit size is 1 millimeter, and the least department of narrow limit size is 0.2 millimeters.

Fig. 5 shows the S-parameters of the simulated angular power division waveguide structure. The S21 parameter represents the energy of the electromagnetic wave transmitted from the input end to the output end of the circular waveguide. As can be seen from the figure, the S21 parameter of the angular power dividing waveguide structure is mostly less than-10 dB, and the S21 is about-8 dB only when the frequency is around 46 GHz. This means that only at frequencies around 46GHz, about 16% of the energy is transferred from the input to the output. At other frequencies, less than 10% of the energy is transmitted from the input to the output, and the remainder is reflected or transmitted into the forward angular power splitting waveguide.

The S12 parameter represents the energy of the electromagnetic wave transmitted from the circular waveguide output end to the input end. As can be seen from the figure, the S12 parameter of the angular power dividing waveguide structure is mostly less than-10 dB, and the S12 is about-8 dB only when the frequency is around 46 GHz. This means that only at frequencies around 46GHz, about 16% of the energy is transferred from the output to the input. At other frequencies, less than 10% of the energy is transmitted from the output to the input, and the remainder is reflected or transmitted into the retro-angular power splitting waveguide.

The S11 parameter characterizes the amount of energy reflected at the input end of the circular waveguide. As can be seen from the figure, the S11 parameter of the angular power dividing waveguide structure is mostly less than-10 dB, and the S11 is about-6.3 dB only when the frequency is around 46 GHz. This means that only at frequencies around 46GHz, the input end has about 23% reflection of energy. At other frequencies, the input end reflects less than 10% of the energy. The rest energy is transmitted to the forward angular power division waveguide or continuously propagates along the circular waveguide.

The S22 parameter characterizes the amount of energy reflected at the output of the circular waveguide. As can be seen from the figure, the S22 parameter of the angular power dividing waveguide structure is mostly less than-10 dB, and the S22 is about-5.4 dB only when the frequency is around 46 GHz. This means that only at frequencies around 46GHz will the output end reflect approximately 28% of the energy. At other frequencies, the output end reflects less than 10% of the energy. The rest energy is transmitted to the backward angular power division waveguide or continuously propagates along the circular waveguide.

The angular power division waveguide structure can guide most of electromagnetic waves generated in the pre-clustering stage in the medium loading section into the rectangular waveguide of the forward angular power division waveguide and be absorbed by the attenuation ceramic chip therein, and can also guide most of high-power electromagnetic waves reflected back to the medium loading section from an output system into the rectangular waveguide of the reverse angular power division waveguide and be absorbed by the attenuation ceramic chip therein. The structure effectively expands the dissipation area of the high-frequency system of the gyrotron traveling wave tube, prevents electromagnetic waves reflected by an output system from directly entering a medium loading section, and improves the power capacity of the medium loading section.