High-power microwave energy transmission window and design method

Abstract

The invention discloses a high-power microwave energy transmission window and a design method, and relates to the technical field of high-power microwave energy transmission windows.The energy transmission window comprises an input square waveguide, a first transition waveguide, a window piece, a second transition waveguide and an output circular waveguide which are connected in sequence; the input square waveguide is connected with the first transition waveguide through a TE10-TE01 mode converter; metal diaphragms are arranged between the TE10-TE01 mode converter and the first transition waveguide and between the second transition waveguide and the output circular waveguide. The TE10-TE01 mode converter is obtained by optimizing a compact 135-degree bent waveguide and a compact one-to-two waveguide; the first transition waveguide and the second transition waveguide are Fourier series outline TE01 transition waveguides; the compact high-efficiency TE10-TE01 mode converter is reduced by about 60% in volume compared with the traditional mode converter of the type; the length of the Fourier wave series contour transition waveguide is shortened by more than 50% compared with that of a conventional conical transition waveguide.

Description

Technical Field

[0001] This invention relates to the field of high-power microwave power transmission window technology, and more specifically, to a high-power microwave power transmission window and its design method. Background Technology

[0002] A microwave power transfer window is a microwave device that can efficiently transmit microwaves and isolate the vacuum environment on both sides. It is a key component of high-power microwave vacuum devices, accelerators and other high-power microwave systems. In recent years, the technology of generating gigawatt (GW) level high-power microwave pulses based on non-relativistic klystrons and pulse compressors has received increasing attention and research. Since existing pulse compressors and antenna feeder systems operate under different vacuum conditions, such high-power microwave systems require the addition of a high-power power transfer window between the pulse compressor and the antenna feeder.

[0003] Traditional power transmission windows include box windows, traveling wave windows, horn windows, and composite mode windows. The pulse power limit of a power transmission window is mainly limited by the electric field on the window surface. For the alumina ceramic material commonly used in power transmission windows, its limiting breakdown field strength in vacuum is 80kV / cm. Therefore, for the same type of power transmission window, the larger the window size, the greater the power that the power transmission window can withstand. The window size of traditional power transmission windows is usually less than twice the diagonal length of a rectangular waveguide. When the window size is further increased, serious problems such as higher-order modes and "ghost modes" will occur. For X-band traditional power transmission windows, the theoretical peak power capacity is 170MW, which cannot meet the application of gigawatt-level high-power microwave systems. Summary of the Invention

[0004] The purpose of this invention is to provide a high-power microwave power transmission window and its design method to solve the problems existing in the background art.

[0005] The above-mentioned technical objective of the present invention is achieved through the following technical solution: In a first aspect, this application provides a high-power microwave power transmission window, comprising an input square waveguide, a first transition waveguide, a window, a second transition waveguide, and an output circular waveguide connected in sequence; The input square waveguide is connected to the first transition waveguide via a TE10-TE01 mode converter; metal diaphragms are provided between the TE10-TE01 mode converter and the first transition waveguide, and between the second transition waveguide and the output circular waveguide.

[0006] Based on the above technical solution, the present invention can be further improved as follows.

[0007] Furthermore, the aforementioned TE10-TE01 mode converter was optimized using a compact 135° bend waveguide and a compact one-to-two waveguide.

[0008] Furthermore, the aforementioned first transition waveguide is a Fourier series profile TE01 transition waveguide.

[0009] Furthermore, the aforementioned second transition waveguide is a Fourier series profile TE01 transition waveguide.

[0010] Secondly, this application provides a design method for a high-power microwave power transmission window, used to design a high-power microwave power transmission window according to any one of the first aspects, wherein the high-power microwave power transmission window is designed by a semi-model slicing simulation optimization method.

[0011] Furthermore, the above-mentioned semi-model slice simulation optimization method includes the following specific steps: The main part of the microwave power transmission window is sliced ​​in the 3D simulation software; The main body of the sliced ​​microwave power window is cut along the middle of the window, while retaining the portion containing the first port; Extend the medium portion of the semi-model away from the first port and set the end as the second port; The thickness of the metal film is fixed, and the position and depth of the metal film are continuously optimized until the reflection coefficient of the model is zero.

[0012] Thirdly, this application provides an electronic device, including: at least one processor, at least one memory, and a data bus; In this system, the processor and memory communicate with each other via a data bus; the memory stores program instructions that can be executed by the processor, and the processor calls the program instructions to execute the method as described in any of the second aspects.

[0013] Fourthly, this application provides a non-transitory computer-readable storage medium that stores computer instructions that cause a computer to perform any of the methods in the second aspect.

[0014] Compared with the prior art, the present invention has at least the following beneficial effects: The high-power microwave power transmission window proposed in this invention is based on the traditional TE01 traveling wave window and includes a TE10-TE01 mode converter, two TE01 transition waveguides, two metal diaphragms, and a window structure. In the circular waveguide TE01 mode, the electric field is 0 at the three-phase point of the window, which can effectively suppress the RF breakdown of the window. The microwaves inside the dielectric window are in a traveling wave state, and the field strength and loss are effectively reduced compared to the standing wave state.

[0015] Since traditional circular waveguide four-sided coupled mode converters have the disadvantage of large size, this invention optimizes the mode converter by using a compact 135° bend waveguide and a compact one-to-two waveguide. The resulting compact high-efficiency TE10-TE01 mode converter is about 60% smaller in size than the traditional mode converter of this type. The Fourier series profile transition waveguide used in this invention has the characteristics of compactness. Under the premise of ensuring high transmission efficiency (transmission coefficient > 99.5%), the length of the Fourier series profile transition waveguide is shortened by more than 50% compared with the conventional tapered transition waveguide. Attached Figure Description

[0016] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the high-power microwave power transmission window in an embodiment of the present invention; Figure 2 This is a schematic diagram of the TE10-TE01 mode converter in an embodiment of the present invention; Figure 3 This is a schematic diagram of the full-model 3D simulation optimization method and the half-model slice simulation optimization method in the embodiments of the present invention; Figure 4 This is a schematic diagram of the X-band high-power transmission window designed in an embodiment of the present invention; Figure 5 This is a schematic diagram of microwave scattering parameters of the X-band high-power transmission window in an embodiment of the present invention. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0018] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0019] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0020] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of the invention is usually placed during use, they are only for the convenience of describing the present invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0021] Furthermore, the use of terms such as "horizontal," "vertical," and "sag" does not imply that the component must be absolutely horizontal or suspended, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0022] In the description of the embodiments of the present invention, "multiple" means at least two.

[0023] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0024] Example 1: To address the issue that traditional power transfer windows cannot meet the requirements of gigawatt-level high-power microwave systems, this example provides a high-power microwave power transfer window, such as... Figure 1 As shown, it includes an input square waveguide, a first transition waveguide, a window, a second transition waveguide, and an output circular waveguide connected in sequence; the input square waveguide and the first transition waveguide are connected by a TE10-TE01 mode converter; metal diaphragms are provided between the TE10-TE01 mode converter and the first transition waveguide, and between the second transition waveguide and the output circular waveguide.

[0025] In a gigawatt-level high-power microwave system based on a non-relativistic klystron, the output port of the microwave power source is generally a rectangular waveguide port. The high-power microwave power transmission window proposed in this invention includes a TE10-TE01 mode converter, two TE01 transition waveguides, two metal diaphragms, and a window structure. The electric field of the circular waveguide TE01 mode is 0 at the three-phase point of the window, which can effectively suppress the radio frequency breakdown of the window. The microwave inside the dielectric window is in a traveling wave state, and the field strength and loss are effectively reduced compared to the standing wave state.

[0026] Optionally, the TE10-TE01 mode converter described above is optimized using a compact 135° bend waveguide and a compact one-to-two waveguide.

[0027] The TE10-TE01 mode converter transforms the TE10 mode of a rectangular waveguide to the TE01 mode of a circular waveguide. Traditional TE01 mode traveling-wave windows employ TE10-TE01 mode converters including petal-type, surround-type, and choke-type converters. These three types of converters are relatively compact, but have high coupling coefficients for low-order and degenerate modes (typically >-40dB). Large windows inevitably experience "ghost mode" problems, and high coupling coefficients for low-order and degenerate modes increase the electric field on the window surface, thus reducing the output window's power capacity. Therefore, this patent uses a circular waveguide four-sided coupled mode converter, which has low coupling coefficients for low-order and degenerate modes (<-50dB), effectively suppressing the influence of "ghost modes."

[0028] Specifically, traditional circular waveguide four-sided coupled mode converters have the disadvantage of large size, such as... Figure 2 As shown, in this embodiment, the mode converter can be optimized using a compact 135° bend waveguide and a compact one-to-two waveguide. The resulting compact high-efficiency TE10-TE01 mode converter is about 60% smaller in size than the traditional mode converter of this type.

[0029] Optionally, the first transition waveguide is a Fourier series profile TE01 transition waveguide; the second transition waveguide is a Fourier series profile TE01 transition waveguide.

[0030] The TE01 transition waveguide serves to transition the circular waveguide operating in TE01 mode from a small size to a large size (or vice versa). Traditional power windows typically employ stepped or tapered transition waveguides. Stepped transition waveguides are generally only suitable for cases where n does not exceed 2 in higher-order TE0n modes, and the large-size window in this embodiment does not fall into this category. The disadvantage of tapered transition waveguides is their relatively long length. In contrast, the Fourier series profile transition waveguide used in this embodiment is highly compact. While ensuring high transmission efficiency (transmission coefficient > 99.5%), the length of the Fourier series profile transition waveguide is reduced by more than 50% compared to conventional tapered transition waveguides.

[0031] Example 2: This application provides a design method for a high-power microwave power transmission window, which is used to design a high-power microwave power transmission window of Example 1. The high-power microwave power transmission window is designed by a semi-model slicing simulation optimization method.

[0032] The design of the traveling wave power transmission window requires ensuring both no reflection at the input port and that the microwaves within the window medium are in a traveling wave state. Traditional design methods include formula calculation and full-model 3D simulation optimization. Formula calculation is convenient and fast, but its accuracy is poor due to the use of approximations. Full-model 3D simulation has higher accuracy, but the simulation optimization time is long for large-sized windows, and the optimization results based on the reflection coefficient cannot guarantee that the microwaves within the window medium are in a traveling wave state. This embodiment proposes a semi-model slicing simulation optimization method, which can not only significantly shorten the simulation optimization time, but also guarantee that the microwaves within the window medium are in a traveling wave state based on the optimization results of the reflection coefficient. Optionally, the above-mentioned semi-model slicing simulation optimization method, such as Figure 3 As shown, the specific steps include the following: S1. The main part of the microwave power transmission window is sliced ​​in the 3D simulation software.

[0033] S2, cut the main body of the sliced ​​microwave power window along the middle of the window, and retain the part containing the first port.

[0034] S3, extend the dielectric portion of the half-model away from the first port, and set the end as the second port; for anisotropic, relative permittivity is ( For dielectric materials (such as sapphire), before setting up waveguide ports, the dielectric properties need to be set to a relative permittivity of 0.5%. Isotropic materials.

[0035] S4, fix the thickness of the metal diaphragm and continuously optimize the position and depth of the metal diaphragm until the reflection coefficient of the model is zero; at this time, there is no reflection at the input port of the traveling wave window, and the microwaves in the window medium are in a traveling wave state.

[0036] Specifically, an X-band high-power transmission window designed using the design method provided in this embodiment is as follows: Figure 4 As shown; Figure 4 The power transmission window in the device includes an input square waveguide, a rectangular waveguide TE10 to a circular waveguide TE01 mode converter, two compact TE01 transition waveguides, a window frame and water jacket (containing the window plate), and an output circular waveguide. The outlet of the output window is directly connected to the antenna feed system, so the output waveguide is a circular waveguide.

[0037] See Figure 5 The microwave network parameters of this X-band high-power transmission window are as follows: Figure 5As shown, its bandwidth with a reflection coefficient < -20dB is approximately ±60MHz, and its bandwidth with a transmission coefficient > 0.99 is approximately ±60MHz, meeting the requirements of high-power microwave applications. The maximum electric field on the window surface is 7.6kV / mm at an input power of 1GW, which is less than the window's ultimate breakdown field strength of 8kV / mm. Theoretically, this window can withstand high-power microwaves greater than 1GW.

[0038] Example 3: This application provides an electronic device, including: at least one processor, at least one memory, and a data bus; In this embodiment, the processor and the memory communicate with each other through a data bus; the memory stores program instructions that can be executed by the processor, and the processor calls the program instructions to execute the method as described in Example 2.

[0039] Example 4: This application provides a non-transitory computer-readable storage medium that stores computer instructions that cause a computer to execute the method of Example 2.

[0040] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0041] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0042] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1The function specified in one or more boxes.

[0043] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0044] Those skilled in the art will understand that all or part of the steps in the above facts and methods can be implemented by a program instructing related hardware. The program or the program described therein can be stored in a computer-readable storage medium. When the program is executed, it includes the following steps: at this time, the corresponding method steps are introduced. The storage medium can be ROM / RAM, magnetic disk, optical disk, etc.

[0045] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A high-power microwave power transmission window, characterized in that, It includes an input square waveguide, a first transition waveguide, a window, a second transition waveguide, and an output circular waveguide connected in sequence; The input square waveguide is connected to the first transition waveguide via a TE10-TE01 mode converter; metal diaphragms are provided between the TE10-TE01 mode converter and the first transition waveguide, and between the second transition waveguide and the output circular waveguide.

2. The high-power microwave transmission window according to claim 1, characterized in that, The TE10-TE01 mode converter is optimized using a compact 135° bend waveguide and a compact one-to-two waveguide.

3. A high-power microwave power transmission window according to claim 1, characterized in that, The first transition waveguide is a Fourier series profile TE01 transition waveguide.

4. A high-power microwave power transmission window according to claim 1, characterized in that, The second transition waveguide is a Fourier series profile TE01 transition waveguide.

5. A design method for a high-power microwave power transmission window, characterized in that, The high-power microwave power transmission window was designed using a semi-model slice simulation optimization method.

6. The design method for a high-power microwave transmission window according to claim 7, characterized in that, The semi-model slice simulation optimization method includes the following specific steps: The main part of the microwave power transmission window is sliced ​​in the 3D simulation software; The main body of the sliced ​​microwave power window is cut along the middle of the window, while retaining the portion containing the first port; Extend the medium portion of the semi-model away from the first port and set the end as the second port; The thickness of the metal film is fixed, and the position and depth of the metal film are continuously optimized until the reflection coefficient of the model is zero.

7. An electronic device, characterized in that, include: At least one processor, at least one memory, and a data bus; The processor and the memory communicate with each other via the data bus. The memory stores program instructions that can be executed by the processor, which invokes the program instructions to perform the method as described in any one of claims 5-6.

8. A non-transitory computer-readable storage medium, characterized in that, The non-transitory computer-readable storage medium stores computer instructions that cause the computer to perform the method of any one of claims 5-6.

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