Slow-wave structure, traveling wave tube, and network device

Abstract

A slow-wave structure, a traveling wave tube, and a network device, relating to the technical field of vacuum electronics. The slow-wave structure comprises a housing, a slow-wave transmission line, an input coupler, and an output coupler. The housing comprises a first housing cover and a second housing cover, which are stacked and connected in a first direction, so that the slow-wave structure is a stacked structure. The slow-wave transmission line is located in a first plane perpendicular to the first direction. Both the input coupler and the output coupler are electrically connected to the slow-wave transmission line. At least one of the input coupler and the output coupler is not coplanar with the first plane, so that the at least one of the input coupler and the output coupler has good consistency with the stacking direction. Therefore, the production and assembly of the input coupler and / or the output coupler are simplified, the degree of integration of the input coupler and the output coupler is improved, and miniaturization of the slow-wave structure is achieved.

Description

Slow-wave structures, traveling wave tubes, and network equipment

[0001] This application claims priority to the Chinese patent application with application number 202311615520.9 filed with the State Intellectual Property Office of China on November 29, 2023, and priority to the Chinese patent application with the invention name “Slow-wave structure, traveling wave tube and network equipment”, all contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the technical field of vacuum electronic devices, and in particular to a slow-wave structure, a traveling wave tube, and a network device. Background Art

[0003] Millimeter-wave power amplifiers include traveling wave tubes (TWTs) and solid-state power amplifiers (SSPAs). Solid-state power amplifiers (SPAs) have lower applicable power, significantly limiting the coverage distance of base stations using them. This requires increasing the number of base stations to meet coverage requirements, increasing deployment costs. Traveling wave tubes (TWTs) have higher applicable power. Using TWT amplifiers can increase the equivalent isotropic radiated power (EIRP) of base stations, thereby reducing the number of base stations and saving deployment costs.

[0004] Traveling wave tubes (TWTs) are categorized by their slow-wave structure, including those with all-metal waveguide slow-wave structures and those with dielectric-supported structures. TWTs with all-metal waveguide slow-wave structures have metal walls whose special structural design folds the electromagnetic wave transmission path, thereby reducing the propagation phase velocity of the electromagnetic wave and enabling energy conversion between the electromagnetic wave and the electron. However, the waveguide modes of TWTs with all-metal waveguide slow-wave structures are transverse electric and transverse magnetic modes (TE and TM modes), which use the total harmonic field to interact with the electron beam, resulting in poor electromagnetic wave amplification.

[0005] A traveling wave tube with a dielectric-supported slow-wave structure comprises a metal slow-wave line, a dielectric support rod, and a metal shell. The metal slow-wave line is used to transmit electromagnetic waves, the dielectric support rod is used to support the metal slow-wave line, and the metal shell serves as a waveguide to enclose the dielectric support rod and the metal slow-wave line. The dielectric support rod and the metal shell are usually made of different materials. The traveling wave tube with a dielectric-supported slow-wave structure has a dual-conductor structure, which makes the waveguide mode of the traveling wave tube with a dielectric-supported slow-wave structure a transverse electromagnetic wave (TEM mode / quasi-TEM mode). Compared with the transverse electric wave / transverse magnetic mode, the transverse electromagnetic wave has a larger electric field and a wider frequency band, which enables the traveling wave tube with a dielectric-supported slow-wave structure to achieve a better amplification effect of electromagnetic waves while being miniaturized. However, the input coupler and output coupler of the traveling wave tube with a dielectric-supported slow-wave structure have a low degree of integration with the waveguide. The input coupler and output coupler have poor consistency with the waveguide assembly method during assembly, which is not conducive to the miniaturization and integration of the traveling wave tube with a dielectric-supported slow-wave structure.

[0006] Summary of the Invention

[0007] The present application provides a slow-wave structure, a traveling wave tube, and a network device. By arranging at least one of the input coupler and the output coupler perpendicular to or parallel to a plane perpendicular to the stacking direction, it is beneficial to simplify the production and assembly of the input coupler and / or the output coupler, improve the integration of the input coupler and the output coupler, and realize the miniaturization of the slow-wave structure.

[0008] In a first aspect, the present application provides a slow-wave structure, comprising: a shell, comprising a first shell cover and a second shell cover stacked and connected along a first direction; a slow-wave transmission line, extending on a first plane perpendicular to the first direction, the slow-wave transmission line being fixed in a first waveguide formed by the first shell cover and the second shell cover; an input coupler and an output coupler, both electrically connected to the slow-wave transmission line, at least one of the input coupler and the output coupler being non-coplanar with the first plane.

[0009] The slow-wave structure provided in the present application includes a housing, a slow-wave transmission line, an input coupler, and an output coupler. The housing includes a first shell cover and a second shell cover stacked in a first direction, so that the slow-wave structure is a stacked structure. During the manufacturing process of the slow-wave structure, each layer structure in the slow-wave structure can be processed separately, which is conducive to achieving planarized batch manufacturing, shortening processing time, and improving the efficiency of slow-wave structure production and processing. At least one of the input coupler and the output coupler is not coplanar with the first plane, so that at least one of the input coupler and the output coupler has good consistency with the stacking direction, that is, at least one of the input coupler and the output coupler has good consistency with the assembly method of the slow-wave structure, which is conducive to simplifying the production and assembly of the input coupler and / or the output coupler, improving the integration of the input coupler and the output coupler, and realizing the miniaturization of the slow-wave structure.

[0010] In one possible embodiment, the input coupler includes a plurality of sequentially connected first metal portions, and the output coupler includes a plurality of sequentially connected second metal portions, wherein two adjacent first metal portions or two adjacent second metal portions form a stepped structure, and at least one of the arrangement direction of the plurality of first metal portions or the arrangement direction of the plurality of second metal portions is at an angle with the first plane. By ensuring that at least one of the arrangement direction of the plurality of first metal portions or the arrangement direction of the plurality of second metal portions is at an angle with the first plane, adjacent first metal portions or adjacent second metal portions are sequentially connected along the stacking direction, thereby simplifying the production and assembly of the input coupler and / or output coupler, improving the integration of the input coupler and output coupler, and achieving miniaturization of the slow-wave structure.

[0011] In one possible embodiment, the input coupler further includes an input coaxial line and a second waveguide. The input coaxial line is electrically connected to the slow-wave transmission line and the plurality of first metal parts. The plurality of first metal parts and at least a portion of the input coaxial line are located within the second waveguide, and the second waveguide is used to couple electromagnetic waves. By including the input coaxial line and the second waveguide in the input coupler, the input coaxial line is used to convert the waveguide mode of the electromagnetic wave from a TEM mode to a quasi-TEM mode, so that the mode of the electromagnetic wave at the slow-wave transmission line is a quasi-TEM mode, thereby improving the amplification effect of the slow-wave structure on the electromagnetic wave.

[0012] In one possible embodiment, the slow-wave structure includes at least one attenuator electrically connected to the output coupler or the input coupler, and configured to absorb electromagnetic waves. Electrically connecting the attenuator to the output coupler or the input coupler helps prevent electromagnetic waves from being reflected by the slow-wave transmission line, improves the stability of electromagnetic wave transmission along the slow-wave transmission line, and thereby ensures the slow-wave structure's amplification effect on electromagnetic waves.

[0013] In one possible embodiment, the slow-wave transmission line includes at least two sections of transmission line, with adjacent sections of the transmission line spaced apart. The slow-wave structure includes at least two attenuators, with each section of the transmission line electrically connected to at least one attenuator. The slow-wave structure also includes at least two spaced couplers, with the spaced couplers electrically connected to the transmission line and the attenuator. By ensuring that the slow-wave transmission line includes at least two sections of transmission line, with a single section of transmission line electrically connected to at least one attenuator, each section of the transmission line is provided with an attenuator for absorbing excess electromagnetic waves, thereby preventing electromagnetic wave reflection at each section of the transmission line and improving the stability of electromagnetic wave transmission at each section of the transmission line.

[0014] In one possible implementation, the input coupler and the output coupler are both non-coplanar with the first plane, while the couplers at the intervals are both coplanar with the first plane. By making the input coupler and the output coupler both non-coplanar with the first plane and the couplers at the intervals coplanar with the first plane, it is advantageous to simplify the configuration of the input and output couplers, improve the integration of the input and output couplers, reduce the space occupied by the attenuator and the couplers at the intervals, and achieve miniaturization of the slow-wave structure.

[0015] In one possible embodiment, at least two of the transmission line segments differ in at least one of the number of periods and the length of the periods. By varying at least one of the number of periods and the length of the periods in the at least two transmission line segments, the rate of decrease of the phase velocity of the electromagnetic wave at each transmission line segment varies, thereby enhancing the amplification effect of the slow-wave structure on the electromagnetic wave.

[0016] In one possible embodiment, the attenuator is wedge-shaped, with a cross-sectional area on the side of the attenuator closer to the coupler at the gap being larger than a cross-sectional area on the side of the attenuator farther from the coupler at the gap, and the cross-sectional area being perpendicular to the direction from the coupler at the gap to the attenuator. The wedge-shaped attenuator helps reduce reflection of electromagnetic waves in the attenuator, enabling the attenuator to absorb electromagnetic waves of a wider frequency range and power.

[0017] In one possible embodiment, the attenuator, the input coupler, and the output coupler are all integrated with the first housing cover. Integrating the attenuator, the input coupler, and the output coupler with the first housing cover facilitates assembly of the input coupler and the output coupler in the stacking direction, provides space for the attenuator, improves the integration of the attenuator, the input coupler, and the output coupler, and facilitates miniaturization of the slow-wave structure.

[0018] In one possible embodiment, the first housing has a first input hole and a first output hole, the input coupler is fixedly connected to the inner wall of the first input hole, and the output coupler is fixedly connected to the inner wall of the first output hole. By fixing the input coupler and the output coupler to the inner wall of the first input hole and the inner wall of the first output hole, respectively, at least a portion of the input coupler and at least a portion of the output coupler are accommodated within the shell layer of the first housing, thereby improving the integration of the input coupler and the output coupler with the first housing and facilitating the miniaturization of the slow-wave structure.

[0019] In one possible embodiment, the slow-wave structure further includes a first energy transmission window and a second energy transmission window. The first energy transmission window seals the first input hole, and the second energy transmission window seals the first output hole. The first energy transmission window is electrically connected to the input coupler and the input waveguide interface, and the second energy transmission window is electrically connected to the output coupler and the output waveguide interface. By including the first energy transmission window and the second energy transmission window in the slow-wave structure, the first energy transmission window and the second energy transmission window respectively seal the first waveguide at the first input hole and the first output hole, thereby ensuring the sealing of the first waveguide.

[0020] In one possible embodiment, the inner wall of at least one of the first input hole and the first output hole has a flange, which supports and connects at least one of the first energy transmission window and the second energy transmission window. Providing a flange on the inner wall of at least one of the first input hole and the first output hole helps improve the stability of the position of the first energy transmission window and / or the second energy transmission window in the slow-wave structure.

[0021] In one possible embodiment, the second housing has a second input hole and a second output hole, the first input hole and the second input hole intersecting in the first direction, and the first output hole and the second output hole intersecting in the first direction. The slow-wave structure also includes a first reflector and a second reflector, the first reflector sealing the second input hole, and the second reflector sealing the second output hole. Providing the second housing with a second input hole and a second output hole, the first reflector sealing the second input hole, and the second reflector sealing the second output hole facilitates ensuring a sealed state within the first waveguide. The provision of the first and second reflectors facilitates phase cancellation between the electromagnetic wave and the original electromagnetic wave after reflection, thereby improving the stability of the electromagnetic wave during transmission.

[0022] In one possible embodiment, one of the first shell cover and the second shell cover includes a circuit layer, and the circuit layer is stacked and connected to the other of the first shell cover and the second shell cover in the first direction. By having one of the first shell cover and the second shell cover include a circuit layer, and the circuit layer is stacked and connected to the other of the first shell cover and the second shell cover in the first direction, the slow-wave transmission line can be integrated with other structures of the slow-wave structure in the stacking direction, thereby improving the integration of the slow-wave transmission line and the shell, and facilitating the miniaturization of the slow-wave structure.

[0023] In one possible embodiment, the slow-wave transmission line is parallel to the first plane, there are at least two slow-wave transmission lines, and the at least two slow-wave transmission lines are stacked and spaced apart in the first direction. By having at least two slow-wave transmission lines, it is advantageous to generate an electric field with a consistent direction, thereby enhancing the amplification effect of the slow-wave structure on electromagnetic waves.

[0024] In one possible implementation, the input coupler and the output coupler are located on the same side of the slow-wave transmission line in the first direction. By locating the input coupler and the output coupler on the same side of the slow-wave transmission line in the first direction, the space occupied by the slow-wave transmission line, the input coupler, and the output coupler in the first direction is reduced, thereby facilitating miniaturization of the slow-wave structure.

[0025] In a second aspect, the present application further provides a traveling wave tube, comprising an electron gun, a collector, a focusing system, an input device, an output device, and the slow-wave structure described in any one of the embodiments of the first aspect, wherein the electron gun and the collector are both fixedly connected to the shell of the slow-wave structure, the electron gun is used to emit electrons into the first waveguide of the slow-wave structure, the collector is used to collect electrons in the first waveguide, the focusing system is used to allow electrons to pass through the slow-wave structure, the input device is electrically connected to the input coupler of the slow-wave structure, the input device is used to send electromagnetic waves to the input coupler, the output device is electrically connected to the output coupler of the slow-wave structure, and the output coupler is used to send amplified electromagnetic waves to the output device. The beneficial effects of this embodiment are similar to those of the above embodiments and will not be repeated in this embodiment.

[0026] In a third aspect, the present application further provides a network device comprising an antenna and the traveling wave tube described in the second aspect, the antenna being electrically connected to the traveling wave tube and configured to transmit electromagnetic waves amplified by the traveling wave tube. The beneficial effects of this embodiment are similar to those of the above-described embodiments and are not further described in this embodiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] FIG1 is a perspective structural diagram of a slow-wave structure provided in an embodiment of the present application;

[0028] FIG2 is an exploded view of the slow-wave structure provided by the embodiment shown in FIG1 ;

[0029] FIG3 is a schematic structural diagram of the first housing cover in the embodiment shown in FIG1 ;

[0030] 4 is a schematic structural diagram of a slow-wave structure provided in an embodiment of the present application, in which both the input coupler and the output coupler are not coplanar with the first plane and no housing is provided;

[0031] 5 is a schematic structural diagram of a slow-wave structure provided in an embodiment of the present application, in which only the input coupler and the first plane are not coplanar and no housing is provided;

[0032] 6 is a schematic structural diagram of a slow-wave structure provided in an embodiment of the present application, in which only the output coupler and the first plane are not coplanar and no housing is provided;

[0033] 7 is a schematic structural diagram of a slow-wave structure without a housing provided in an embodiment of the present application, having a single-segment transmission line and a single attenuator;

[0034] FIG8 is a schematic structural diagram of a slow-wave structure without a housing provided in an embodiment of the present application, having two transmission lines and two attenuators;

[0035] 9 is a schematic structural diagram of a slow-wave structure without a housing provided in an embodiment of the present application, having three transmission lines and four attenuators;

[0036] FIG10 is a schematic structural diagram of a slow-wave structure having an energy transmission window and a reflector provided in an embodiment of the present application;

[0037] FIG11 is an exploded view of the slow-wave structure provided by the embodiment shown in FIG10 ;

[0038] FIG12 is a perspective structural diagram of the inner wall of the first input hole and the first energy transmission window provided in an embodiment of the present application;

[0039] FIG13 is an exploded view of the inner wall of the first input hole and the first energy transmission window provided in the embodiment shown in FIG12 ;

[0040] FIG14 is a system schematic diagram of a traveling wave tube provided in an embodiment of the present application;

[0041] FIG15 is a system diagram of a network device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0042] The embodiments of the present application are described below in conjunction with the drawings in the embodiments of the present application.

[0043] For ease of understanding, the English abbreviations and related technical terms involved in the embodiments of this application are explained and described below.

[0044] It should be clear that the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0045] The terms used in the embodiments of the present application are for the purpose of describing specific embodiments only and are not intended to limit the present application. The singular forms "a", "an", "the" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise.

[0046] It should be understood that the term "and / or" as used herein is simply a term used to describe the existence of three possible relationships between related objects. For example, "A and / or B" can represent the existence of A alone, the existence of both A and B, and the existence of B alone. Furthermore, the character " / " in this document generally indicates that the related objects are in an "or" relationship.

[0047] The word "if," as used herein, may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting," depending on the context. Similarly, the phrases "if it is determined" or "if (stated condition or event) is detected" may be interpreted as "when it is determined" or "in response to the determination" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)," depending on the context.

[0048] It should be understood that the terms “first”, “second”, etc. used in this application are only used for the purpose of distinguishing descriptions, and cannot be understood as indicating or implying relative importance, nor can they be understood as indicating or implying an order.

[0049] In the description of this application, the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limiting this application.

[0050] In the description of this application, it should be noted that due to manufacturing errors or assembly errors, there are some angular deviations in the design that should be vertical or parallel. For example, the deviation is within 15 degrees, which also falls within the vertical or parallel described in this embodiment.

[0051] When used in this application, "within the range of...", unless it is specifically stated that the end value is not included, it is assumed that both end values ​​of the range are included. For example, in the range of 1 to 5, the two values ​​1 and 5 are included.

[0052] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "install", "connect" and "connect" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, a conflicting connection or an integrated connection. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0053] It should be understood that in this application, "electrical connection" can be understood as physical contact and electrical conduction between components; it can also be understood as the connection between different components in a circuit structure through physical lines such as printed circuit board (PCB) copper foil or wires that can transmit signals. "Connection" and "connected" can both refer to a mechanical or physical connection relationship. For example, "A and B are connected" or "A and B are connected" can mean that there is a fastening member (such as a screw, bolt, rivet, etc.) between A and B, or that A and B are in contact with each other and A and B are difficult to separate.

[0054] In this application, electrical length may refer to the physical length (i.e., mechanical length or geometric length) multiplied by the ratio of the propagation time of an electrical or electromagnetic signal in a medium to the time required for the signal to travel the same distance as the physical length of the medium in free space. The electrical length may satisfy the following formula:

[0055]

[0056] Where L is the physical length, a is the propagation time of the electrical or electromagnetic signal in the medium, and b is the propagation time in free space.

[0057] Alternatively, electrical length can also refer to the ratio of physical length (i.e., mechanical length or geometric length) to the wavelength of the transmitted electromagnetic wave. The electrical length can satisfy the following formula:

[0058]

[0059] Where L is the physical length and λ is the wavelength of the electromagnetic wave.

[0060] Coupling: refers to the phenomenon in which the input and output of two or more circuit elements or electrical networks are closely coordinated and influenced by each other, and energy is transmitted from one side to the other through interaction.

[0061] Millimeter-wave transmitters offer the advantages of wide bandwidth and high linearity, meeting the ultra-high-capacity transmission requirements of communication systems and bringing significant advantages to millimeter-wave communication systems. The millimeter-wave power amplifier (MPA) is a core component of a millimeter-wave transmitter, and its performance directly determines the cost, size, and transmission performance of the transmitter. MWAs include solid-state PAs and traveling wave tubes (TWTs). The lower power of SPAs results in lower output power for millimeter-wave transmitters using SPAs. This limits base station coverage distance, necessitating an increase in the number of base stations to meet coverage requirements, and increasing base station deployment costs.

[0062] A traveling wave tube (TWT) is a microwave electron tube that amplifies electromagnetic waves by synchronizing the speed of an electron beam with the phase velocity of an electromagnetic wave. In a TWT, the electron beam interacts with the electromagnetic wave traveling through a slow-wave circuit, continuously transferring kinetic energy to the electromagnetic wave, thereby amplifying the wave. Because it uses a slow-wave structure to interact with the electron beam rather than a resonant cavity, the TWT boasts a wide operating frequency band, high efficiency, and high output power.

[0063] The slow-wave structure is a device designed to enhance the interaction between electrons and electromagnetic fields in a traveling wave tube, more efficiently converting the energy of the electron stream into high-frequency electromagnetic energy. Because electromagnetic waves propagate at the speed of light in a vacuum, while the speed of an electron beam in a vacuum is much slower than the speed of light, a specific high-frequency structure must be used to slow the motion of the electromagnetic wave's isophase plane in order to enable interaction between the electromagnetic wave and the electron beam. This means that the phase velocity of the electromagnetic wave must be slowed down so that the electron's travel speed approaches that of the electromagnetic wave, thereby satisfying synchronization requirements.

[0064] Slow-wave structures include all-metal waveguide slow-wave structures and dielectric-supported slow-wave structures. The all-metal waveguide slow-wave structure is made of all-metal, which is more convenient for processing and manufacturing. The slow-wave structure includes a hollow metal waveguide tube, which is used to deform or fold the electromagnetic wave transmission path to reduce the propagation phase velocity of the electromagnetic wave, thereby achieving energy conversion between the electromagnetic wave and the electron. The all-metal waveguide slow-wave structure operates in the transverse electric wave / transverse magnetic mode (TE mode / TM mode). During the transmission of electromagnetic waves, the electromagnetic wave transmission speed in the TE mode / TM mode is faster. Therefore, more electromagnetic wave transmission paths need to be folded to reduce the phase velocity of the electromagnetic wave to the required range. This increases the length of the hollow metal waveguide tube in the transmission direction of the electromagnetic wave, resulting in an increase in the structural size of the all-metal waveguide slow-wave structure, which cannot meet the requirements of miniaturization. At the same time, because this type of waveguide needs to operate on spatial harmonics to achieve the slow-wave effect, the electric field of the electromagnetic wave transmitted by the hollow metal waveguide tube in the transmission direction is relatively small, resulting in poor amplification effect of the all-metal waveguide slow-wave structure on the electromagnetic wave.

[0065] The dielectric-supported slow-wave structure includes a metal slow-wave line, a dielectric support rod, and a metal shell, which are arranged in sequence. The metal slow-wave line is used to transmit electromagnetic waves. The structure of the metal slow-wave line is a curved structure, so that the path of the electromagnetic wave when it is transmitted at the metal slow-wave line is folded, thereby reducing the propagation phase velocity of the electromagnetic wave, thereby realizing the energy conversion between the electromagnetic wave and the electron. The metal shell acts as a waveguide to enclose the dielectric support rod and the metal slow-wave line. The material of the dielectric support rod is different from that of the metal shell. The material of the dielectric support rod is usually ceramic. The dielectric-supported slow-wave structure has a dual-conductor structure, so that the waveguide mode of the dielectric-supported slow-wave structure is a transverse electromagnetic wave (TEM mode / quasi-TEM mode). Compared with the TE mode / TM mode, the TEM mode / quasi-TEM mode has a wider bandwidth and is easier to reduce the phase velocity of the electromagnetic wave to the required range at a smaller size. At the same time, because this type of slow-wave structure operates on the first spatial harmonic of the TEM mode, the electric field of the electromagnetic wave transmitted by the metal slow-wave line is larger in the transmission direction, which makes the dielectric-supported slow-wave structure have a better amplification effect on the electromagnetic wave.

[0066] The dielectric-supported slow-wave structure is more conducive to the miniaturization of traveling wave tubes. However, the integration of the input coupler and output coupler of the dielectric-supported slow-wave structure with the waveguide is currently low, and the input coupler and output coupler are poorly consistent with the waveguide assembly method during the assembly process, making the assembly of the dielectric-supported traveling wave tube more complicated and prone to errors, which is not conducive to the further miniaturization of the dielectric-supported traveling wave tube.

[0067] The present application provides a slow-wave structure 100, as shown in Figures 1 and 2. Figure 1 shows a perspective structural diagram of the slow-wave structure 100 provided in an embodiment of the present application, and Figure 2 shows an exploded view of the slow-wave structure 100 provided in the embodiment shown in Figure 1. The slow-wave structure 100 includes a housing 10 and a slow-wave transmission line 20. The housing 10 includes a first housing cover 11 and a second housing cover 12 stacked and connected along a first direction (Z direction in Figure 1). The first housing cover 11 and the second housing cover 12 enclose a first waveguide 13, and the slow-wave transmission line 20 is fixed within the first waveguide 13.

[0068] The first waveguide 13 is used to pass electrons. The first waveguide 13 can extend in a straight line. The extension direction of the first waveguide 13 is a second direction (the Y direction in Figure 1), and the second direction can be perpendicular to the first direction. The channel area of ​​the first waveguide 13 perpendicular to the second direction can remain unchanged in the second direction to ensure the consistency of the channel area of ​​the first waveguide 13 along its extension direction, prevent electrons from being blocked by the inner wall of the first waveguide 13 during movement within the first waveguide 13, and improve the space utilization of the first waveguide 13. The cross-sectional shape of the first waveguide 13 includes but is not limited to a circular or rectangular shape, and can be set according to actual needs.

[0069] The slow-wave transmission line 20 is used to transmit electromagnetic waves. The slow-wave transmission line 20 is fixed in the first waveguide 13 . The electromagnetic waves transmitted by the slow-wave transmission line 20 interact with the electrons in the first waveguide 13 to achieve amplification of the electromagnetic waves.

[0070] The slow-wave transmission line 20 has a folded structure, which folds the path of electromagnetic waves propagating through the metal slow-wave line, thereby reducing the propagation phase velocity of the electromagnetic waves. The slow-wave transmission line 20 can extend linearly along the second direction. The extension direction of the slow-wave transmission line 20 is the same as the extension direction of the first waveguide 13. This ensures that the overall propagation direction of the electromagnetic waves through the slow-wave transmission line 20 is the same as the propagation direction of electrons within the first waveguide 13.

[0071] Referring to FIG. 4 , FIG. 4 illustrates a schematic structural diagram of a slow-wave structure 100 provided in an embodiment of the present application, wherein both the input coupler 30 and the output coupler 40 are not coplanar with the first plane 26. The slow-wave transmission line 20 can extend along the first plane 26, which is one of the planes perpendicular to the first direction. The slow-wave transmission line 20 extends entirely along a second direction on the first plane 26, with the central axis of the slow-wave transmission line 20 located on the first plane 26, such that the slow-wave transmission line 20 is symmetrically disposed relative to the first plane 26.

[0072] In one embodiment, the slow-wave transmission line 20 can be extended spirally along the second direction. During the spiral extension of the slow-wave transmission line 20, the radius of a single spiral can remain unchanged to ensure the consistency of the path folding degree at each position when the electromagnetic wave is transmitted at the metal slow-wave line.

[0073] In one embodiment, the slow-wave transmission line 20 may also bend and extend along the second direction on the first plane 26. The slow-wave transmission line 20 includes a plurality of curved lines connected end to end. The shapes and sizes of the plurality of curved lines may be the same. The shapes of the plurality of curved lines include but are not limited to U-shape, V-shape or S-shape.

[0074] The slow-wave structure 100 also includes an input coupler 30 and an output coupler 40. Both the input coupler 30 and the output coupler 40 are electrically connected to the slow-wave transmission line 20. The input coupler 30 is used to input electromagnetic waves into the slow-wave transmission line 20. During the process of transmitting electromagnetic waves by the slow-wave transmission line 20, the electrons in the first waveguide 13 interact with the electromagnetic wave field of the electromagnetic wave. The electrons continuously transfer kinetic energy to the electromagnetic wave field, so that the electromagnetic wave is amplified. The slow-wave transmission line 20 transmits the amplified electromagnetic wave to the output coupler 40, and the output coupler 40 then outputs the amplified electromagnetic wave from the slow-wave structure 100.

[0075] At least one of the input coupler 30 and the output coupler 40 is not coplanar with the first plane 26. In one embodiment, referring to FIG4 , the input coupler 30 and the output coupler 40 may both be non-coplanar with the first plane 26. In one embodiment, referring to FIG5 , FIG5 shows a schematic structural diagram of a slow-wave structure 100 provided in an embodiment of the present application, in which only the input coupler 30 and the first plane 26 are not coplanar, and the housing 10 is not provided. The input coupler 30 may be non-coplanar with the first plane 26, and the output coupler 40 may be coplanar with the first plane 26. In one embodiment, referring to FIG6 , FIG6 shows a schematic structural diagram of a slow-wave structure 100 provided in an embodiment of the present application, in which only the output coupler 40 and the first plane 26 are not coplanar, and the housing 10 is not provided. The input coupler 30 may be coplanar with the first plane 26, and the output coupler 40 may be non-coplanar with the first plane 26.

[0076] At least one of the input coupler 30 and the output coupler 40 is not coplanar with the first plane 26, which means that at least one of the input coupler 30 and the output coupler 40 is not parallel to the first plane 26, and at least one of the input coupler 30 and the output coupler 40 is not located on the first plane 26. The input coupler 30 and the output coupler 40 may both have an angle with the first plane 26; or the input coupler 30 may have an angle with the first plane 26 and the output coupler 40 may be parallel to the first plane 26; or the input coupler 30 may be parallel to the first plane 26 and the output coupler 40 may have an angle with the first plane 26.

[0077] Illustratively, the input coupler 30 and the output coupler 40 are both perpendicular to the first plane 26; or, the input coupler 30 is perpendicular to the first plane 26 and the output coupler 40 is parallel to the first plane 26; or, the input coupler 30 is parallel to the first plane 26 and the output coupler 40 is perpendicular to the first plane 26.

[0078] The housing 10 includes a first shell cover 11 and a second shell cover 12 stacked and connected along a first direction. The slow-wave structure 100 can be a stacked structure. During the manufacturing process of the slow-wave structure 100, each layer structure in the slow-wave structure 100 can be processed separately, so that each layer structure in the slow-wave structure 100 can be processed simultaneously, which is conducive to achieving planar batch manufacturing, shortening processing time, and improving the efficiency of the production and processing of the slow-wave structure 100; at the same time, the processed layer structures can be assembled sequentially along the stacking direction. The assembly method in the stacking direction has a small error and is more suitable for industrial production and manufacturing, which is conducive to simplifying the processing and assembly process of the slow-wave structure 100, improving the production accuracy and yield of the slow-wave structure 100, and improving the amplification effect and stability of the slow-wave structure 100 on electromagnetic waves.

[0079] At least one of the input coupler 30 and the output coupler 40 is not coplanar with the first plane 26. During the arrangement process, at least one of the input coupler 30 and the output coupler 40 forms an angle with the first plane 26, so that the arrangement direction of at least one of the input coupler 30 and the output coupler 40 is well consistent with the stacking direction. When processing the input coupler 30 or the output coupler 40, at least one of the input coupler 30 and the output coupler 40 can be integrated with other structures of the slow-wave structure 100 in the stacking direction, thereby improving the integration level of at least one of the input coupler 30 and the output coupler 40 and facilitating the miniaturization of the slow-wave structure 100. Furthermore, this facilitates assembly of the input coupler 30 or the output coupler 40 in the stacking direction in conjunction with the stacking connection of the first shell 11 and the second shell 12, simplifying the arrangement of the input coupler 30 and / or the output coupler 40 and making the assembly of the input coupler 30 or the output coupler 40 more convenient for industrial production.

[0080] The slow-wave structure 100 provided in the present application includes a shell 10, a slow-wave transmission line 20, an input coupler 30 and an output coupler 40. The input coupler 30 and the output coupler 40 are both electrically connected to the slow-wave transmission line 20. The shell 10 encloses the first waveguide 13, and the slow-wave transmission line 20 is fixed in the first waveguide 13, so that electromagnetic waves can be transmitted through the slow-wave transmission line 20. The electrons in the first waveguide 13 can act on the electromagnetic waves transmitted by the slow-wave transmission line 20 to achieve amplification of the electromagnetic waves. The slow-wave structure 100 adopts the TEM mode / quasi-TEM mode, which is conducive to ensuring that the electromagnetic waves have a good amplification effect.

[0081] The shell 10 includes a first shell cover 11 and a second shell cover 12 stacked along a first direction, so that the slow-wave structure 100 is a stacked structure. During the manufacturing process of the slow-wave structure 100, each layer structure in the slow-wave structure 100 can be processed separately, which is conducive to achieving planar batch manufacturing, shortening the processing time, and improving the production and processing efficiency of the slow-wave structure 100; at the same time, at least one of the input coupler 30 and the output coupler 40 is not coplanar with the first plane 26, so that at least one of the input coupler 30 and the output coupler 40 has good consistency with the stacking direction, that is, at least one of the input coupler 30 and the output coupler 40 has good consistency with the assembly method of the slow-wave structure 100, which is conducive to simplifying the production and assembly of the input coupler 30 and / or the output coupler 40, improving the integration of the input coupler 30 and the output coupler 40, and realizing the miniaturization of the slow-wave structure 100.

[0082] In one possible embodiment, as shown in Figure 4, the input coupler 30 includes a first mode converter 31, and the output coupler 40 includes a second mode converter 41. The first mode converter 31 is used to convert the waveguide mode of the electromagnetic wave from the TE mode to the TEM mode; the second mode converter 41 is used to convert the mode of the electromagnetic wave from the TEM mode to the TE mode, so that the mode of the electromagnetic wave when it is output is the TE mode.

[0083] The first mode converter 31 includes multiple first metal portions 311, which are connected in sequence, with adjacent pairs of first metal portions 311 forming a staircase structure. Similarly, the second mode converter 41 includes multiple second metal portions 411, which are connected in sequence, with adjacent pairs of second metal portions 411 forming a staircase structure. At least one of the first mode converter 31 and the second mode converter 41 is not coplanar with the first plane 26. Specifically, at least one of the arrangement direction of the multiple first metal portions 311 and the arrangement direction of the multiple second metal portions 411 forms an angle with the first plane 26.

[0084] 4 , when both the first mode converter 31 and the second mode converter 41 are not coplanar with the first plane 26 , the arrangement direction of the plurality of first metal portions 311 and the arrangement direction of the plurality of second metal portions 411 both have an angle with the first plane 26 ; referring to FIG5 , when the first mode converter 31 is not coplanar with the first plane 26 and the second mode converter 41 is coplanar with the first plane 26 , the arrangement direction of the plurality of first metal portions 311 has an angle with the first plane 26 , and the arrangement direction of the plurality of second metal portions 411 is parallel to the first plane 26 ; referring to FIG6 , when the first mode converter 31 is coplanar with the first plane 26 and the second mode converter 41 is not coplanar with the first plane 26 , the arrangement direction of the plurality of first metal portions 311 is parallel to the first plane 26 , and the arrangement direction of the plurality of second metal portions 411 has an angle with the first plane 26 .

[0085] Exemplarily, the arrangement direction of the multiple first metal parts 311 and the arrangement direction of the multiple second metal parts 411 are both perpendicular to the first plane 26; or, the arrangement direction of the multiple first metal parts 311 is perpendicular to the first plane 26, and the arrangement direction of the multiple second metal parts 411 is parallel to the first plane 26; or, the arrangement direction of the multiple first metal parts 311 is parallel to the first plane 26, and the arrangement direction of the multiple second metal parts 411 is perpendicular to the first plane 26.

[0086] When manufacturing the input coupler 30 and the output coupler 40, the one of the first mode converter 31 and the second mode converter 41 that is not coplanar with the first plane 26 can be integrated with other structures of the slow-wave structure 100 in the stacking direction. That is, at least one of the multiple first metal parts 311 and the multiple second metal parts 411 is sequentially arranged in the stacking direction, and two adjacent first metal parts 311 or two adjacent second metal parts 411 are sequentially connected along the stacking direction. This helps to simplify the production and assembly of the input coupler 30 and / or the output coupler 40, improve the integration of the input coupler 30 and the output coupler 40, and achieve miniaturization of the slow-wave structure 100. The two adjacent first metal parts 311 or the two adjacent second metal parts 411 can be sequentially welded along the stacking direction so that the multiple first metal parts 311 form an integrated first mode converter 31 or the multiple second metal parts 411 form an integrated second mode converter 41.

[0087] For example, referring to Figure 4, the first mode converter 31 and the second mode converter 41 are both perpendicular to the first plane 26, and the arrangement direction of the multiple first metal parts 311 and the arrangement direction of the multiple second metal parts 411 are both perpendicular to the first plane 26. When processing the input coupler 30 and the output coupler 40, the multiple first metal parts 311 and the multiple second metal parts 411 are connected in sequence in the stacking direction, and the volumes of the multiple first metal parts 311 and the multiple second metal parts 411 in the stacking direction are reduced in sequence, so that two adjacent first metal parts 311 or two adjacent second metal parts 411 form a stepped structure in the stacking direction.

[0088] For example, referring to FIG5 , the first mode converter 31 is perpendicular to the first plane 26 , the second mode converter 41 is parallel to the first plane 26 , the arrangement direction of the plurality of first metal parts 311 is perpendicular to the first plane 26 , and the arrangement direction of the plurality of second metal parts 411 is parallel to the first plane 26 . When processing the input coupler 30 , the plurality of first metal parts 311 are connected sequentially in the stacking direction, thereby simplifying the production and assembly of the input coupler 30 and improving the integration of the input coupler 30 .

[0089] In one embodiment, referring to Figures 2, 3, and 4, Figure 3 shows a schematic structural diagram of the first shell cover in the embodiment shown in Figure 1. The input coupler 30 also includes an input coaxial line 32 and a second waveguide 33. The input coaxial line 32 is electrically connected to the slow-wave transmission line 20 and the first mode converter 31. The input coaxial line 32 is used to convert the waveguide mode of the electromagnetic wave from a TEM mode to a quasi-TEM mode, so that the mode of the electromagnetic wave at the slow-wave transmission line 20 is a quasi-TEM mode. The input coaxial line 32 can be electrically connected to the slow-wave transmission line 20 and the first mode converter 31 at both ends respectively. The input coaxial line 32 is electrically connected to the plurality of first metal parts 311. The input coaxial line 32 can be directly connected to a single first metal part 311 located at the end of the plurality of first metal parts 311, that is, the input coaxial line 32 can be in contact with the single first metal part 311 located at the end of the plurality of first metal parts 311. The plurality of first metal parts 311 and at least a portion of the input coaxial line 32 are located in the second waveguide 33 . The second waveguide 33 is used for coupling electromagnetic waves so that the electromagnetic waves are transmitted from the input coupler 30 to the slow-wave transmission line 20 .

[0090] Similarly, the output coupler 40 includes an output coaxial line 42 and a third waveguide 43. The output coaxial line 42 is electrically connected to the slow-wave transmission line 20 and the second mode converter 41. The output coaxial line 42 is used to convert the waveguide mode of the electromagnetic wave from the quasi-TEM mode to the TEM mode, so that the mode of the electromagnetic wave transmitted from the slow-wave transmission line 20 to the second mode converter 41 is the TEM mode. The output coaxial line 42 can be electrically connected to the slow-wave transmission line 20 and the second mode converter 41 at both ends, and the input coaxial line 32 can be directly connected to a single second metal part 411 located at the end of the multiple second metal parts 411. The multiple second metal parts 411 and at least part of the output coaxial line 42 are located in the third waveguide 43. The third waveguide 43 is used to couple electromagnetic waves so that the amplified electromagnetic waves are output from the slow-wave transmission line 20.

[0091] The input coaxial line 32 and the output coaxial line 42 can both extend along a straight line, and the extension direction of the input coaxial line 32 and the extension direction of the output coaxial line 42 can both be parallel to the first plane 26. Compared with the case where the extension direction of the input coaxial line 32 and the extension direction of the output coaxial line 42 both have an angle with the first plane 26, the space occupied by the input coupler 30 and the output coupler 40 in the first direction (Z direction in Figure 4) is reduced, which is conducive to simplifying the setting method of the input coaxial line 32 and the output coaxial line 42, and making full use of the space of the slow-wave structure 100 on the first plane 26.

[0092] In one embodiment, referring to Figures 4, 5, and 6, the input coupler 30 and the output coupler 40 are both located on the same side of the slow-wave transmission line 20 in the first direction (the Z direction in Figures 4 to 6), that is, the input coupler 30 and the output coupler 40 are both located on the same side of the slow-wave transmission line 20 in the stacking direction. When processing the input coupler 30 and the output coupler 40, the input coupler 30 and the output coupler 40 can be integrated simultaneously, which helps simplify the production and assembly of the input coupler 30 and the output coupler 40. At the same time, compared to the case where the input coupler 30 and the output coupler 40 are respectively located on opposite sides of the slow-wave transmission line 20 in the first direction, the space occupied by the slow-wave transmission line 20, the input coupler 30, and the output coupler 40 in the first direction is reduced, which helps to achieve miniaturization of the slow-wave structure 100.

[0093] The input coupler 30 and the output coupler 40 can be directly connected to the two ends of the slow-wave transmission line 20 respectively, that is, the input coupler 30 and the output coupler 40 can be directly in contact with the two ends of the slow-wave transmission line 20 respectively, so that the extension length of the slow-wave transmission line 20 in the second direction is fully utilized, which is conducive to the miniaturization of the slow-wave structure 100.

[0094] The slow-wave transmission line 20 extends along the second direction (the Y direction in Figures 4 to 6), and the input coaxial line 32 and the output coaxial line 42 can both extend along the third direction (the X direction in Figures 4 to 6), which is perpendicular to both the second direction and the first direction. At this time, the two ends of the input coaxial line 32 are respectively connected to the multiple first metal parts 311 and the slow-wave transmission line 20, and the two ends of the output coaxial line 42 are respectively connected to the multiple second metal parts 411 and the slow-wave transmission line 20, so that the multiple first metal parts 311 and the multiple second metal parts 411 are all spaced apart from the slow-wave transmission line 20, providing space for the arrangement of the slow-wave transmission line 20 and the transmission of electrons in the first waveguide 13. The input coupler 30 and the output coupler 40 can be respectively located on both sides of the slow-wave transmission line 20 in the third direction, so that the input coupler 30 and the output coupler 40 are staggered compared to the slow-wave transmission line 20, which facilitates the identification of the input device 203 and the output device 204 when they are respectively connected to the input coupler 30 and the output coupler 40 of the slow-wave structure 100.

[0095] In one possible embodiment, referring to Figures 7 and 8, Figure 7 shows a schematic structural diagram of a slow-wave structure 100 provided in an embodiment of the present application, having a single-segment transmission line and a single attenuator 60 without a housing 10. Figure 8 shows a schematic structural diagram of a slow-wave structure 100 provided in an embodiment of the present application, having two-segment transmission lines and two attenuators 60 without a housing 10. The slow-wave structure 100 includes at least one attenuator 60, which is used to absorb electromagnetic waves. The single attenuator 60 is electrically connected to the input coupler 30 or the output coupler 40. The single attenuator 60 is indirectly electrically connected to the input coupler 30 via the slow-wave transmission line 20, which is located between the input coupler 30 and the attenuator 60. The single attenuator 60 can be electrically connected to the output coupler 40 either indirectly via the slow-wave transmission line 20 or directly. When the attenuator 60 is directly electrically connected to the output coupler 40, the single attenuator 60 is directly in contact with the output coupler 40.

[0096] In one embodiment, as shown in FIG7 , the slow-wave transmission line 20 is a single-segment transmission line, and the input coupler 30 and the output coupler 40 are directly connected to both ends of the slow-wave transmission line 20. The slow-wave structure 100 includes a single attenuator 60, which is directly connected to the output coupler 40. When electromagnetic waves are transmitted from the input coupler 30 to the output coupler 40 via the slow-wave transmission line 20, most of the electromagnetic waves can be output from the output coupler 40. To prevent part of the electromagnetic waves from being reflected at the output coupler 40 to the slow-wave transmission line 20, thereby affecting the electromagnetic waves in the slow-wave transmission line 20 during transmission, the output coupler 40 is electrically connected to the attenuator 60. The attenuator 60 absorbs excess electromagnetic waves at the output coupler 40, which helps to prevent electromagnetic waves from being reflected to the slow-wave transmission line 20, improves the stability of electromagnetic wave transmission at the slow-wave transmission line 20, and thereby ensures the amplification effect of the slow-wave structure 100 on electromagnetic waves.

[0097] In one embodiment, referring to Figures 8 and 9, Figure 9 shows a schematic structural diagram of a slow-wave structure 100 provided in an embodiment of the present application, having three transmission lines and four attenuators 60, but without a housing 10. The slow-wave transmission line 20 includes at least two transmission lines, which are arranged sequentially in the second direction, with adjacent transmission lines spaced apart, and with a gap between adjacent transmission lines in the second direction. An input coupler 30 and an output coupler 40 are located at both ends of the slow-wave transmission line 20, and are electrically connected to the two transmission lines at both ends, respectively. When the slow-wave transmission line 20 includes at least two sections of transmission lines, the electromagnetic wave is transmitted sequentially at the at least two sections of transmission lines, and the two adjacent sections of transmission lines are spaced apart. By setting the spacing between the two adjacent sections of transmission lines, the electromagnetic wave transmission path can be cut off at the spacing between the two adjacent sections of transmission lines; at the same time, the electron beam used to interact with the electromagnetic wave at the spacing can enter the next section of the slow-wave line without being intercepted under the constraint of the magnetic field, and stimulate the corresponding electromagnetic field to continue to interact with the electromagnetic wave, thereby helping to improve the amplification effect of the electromagnetic wave.

[0098] The slow-wave structure 100 also includes at least two couplers 50 at the intervals, and the couplers 50 at the intervals are electrically connected to one end of the two adjacent transmission lines at the intervals. The two ends of one of the two transmission lines at the two ends are respectively electrically connected to the input coupler 30 and the coupler 50 at the intervals, and the two ends of the other section are respectively electrically connected to the output coupler 40 and the coupler 50 at the intervals.

[0099] The slow-wave structure 100 includes at least two attenuators 60, which are electrically connected to the couplers 50 at the intervals. The number of couplers 50 at the intervals is the same as the number of attenuators 60. The input coupler 30 and the output coupler 40 are both indirectly electrically connected to the attenuator 60 through the transmission line, and the coupler 50 at the intervals is directly electrically connected to the attenuator 60, that is, the coupler 50 at the intervals is in direct contact with the attenuator 60. The coupler 50 at the intervals is electrically connected to both the transmission line and the attenuator 60, so that the coupler 50 at the intervals is located between the transmission line and the attenuator 60. Each section of the transmission line is electrically connected to at least one attenuator 60, so that each section of the transmission line is provided with an attenuator 60 for absorbing excess electromagnetic waves, thereby avoiding reflection of electromagnetic waves at each section of the transmission line, and facilitating the stability of electromagnetic wave amplification in each section of the transmission line.

[0100] Assuming the number of transmission lines included in the slow-wave transmission line 20 is n and the number of attenuators 60 in the slow-wave structure 100 is m, when the slow-wave transmission line 20 includes at least two transmission line segments, the number of transmission lines and the number of attenuators 60 satisfy the relationship: m = 2 × (n - 1). By ensuring that the slow-wave structure 100 satisfies this relationship, each transmission line segment is electrically connected to at least one attenuator 60, which helps improve the stability of electromagnetic wave transmission in each transmission line segment.

[0101] For example, referring to FIG8 , the slow-wave transmission line 20 includes two transmission line sections, namely a first transmission line 21 and a second transmission line 22. The two ends of the first transmission line 21 are electrically connected to the input coupler 30 and the coupler 51 at the first interval, respectively. The two ends of the second transmission line 22 are electrically connected to the output coupler 40 and the coupler 52 at the second interval, respectively. The slow-wave structure 100 includes two attenuators 60, namely a first attenuator 61 and a second attenuator 62. The first attenuator 61 is electrically connected to the coupler 51 at the first interval, and the second attenuator 62 is electrically connected to the coupler 52 at the second interval.

[0102] For example, referring to FIG9 , the slow-wave transmission line 20 includes three transmission line sections, namely a first transmission line 21, a second transmission line 22, and a third transmission line 23. The first transmission line 21 and the second transmission line 22 are located at opposite ends of the slow-wave transmission line 20, respectively, and the third transmission line 23 is located in the middle region of the slow-wave transmission line 20. The two ends of the first transmission line 21 are electrically connected to the input coupler 30 and the coupler 51 at the first interval, respectively. The two ends of the second transmission line 22 are electrically connected to the output coupler 40 and the coupler 52 at the second interval, respectively. The two ends of the third transmission line 23 are electrically connected to the coupler 53 at the third interval and the coupler 54 at the fourth interval, respectively. The slow-wave structure 100 includes four attenuators 60, which are respectively a first attenuator 61, a second attenuator 62, a third attenuator 63 and a fourth attenuator 64. The first attenuator 61 is electrically connected to the coupler 51 at the first interval, the second attenuator 62 is electrically connected to the coupler 52 at the second interval, the third attenuator 63 is electrically connected to the coupler 53 at the third interval, and the fourth attenuator 64 is electrically connected to the coupler 54 at the fourth interval, so that the two ends of the third transmission line 23 are electrically connected to the third attenuator 63 and the fourth attenuator 64 respectively.

[0103] In a possible embodiment, referring to Figures 8 and 9, the input coupler 30 and the output coupler 40 are not coplanar with the first plane 26, so that the setting direction of the input coupler 30 and the output coupler 40 are well consistent with the stacking direction. The input coupler 30 and the output coupler 40 can be integrated with other structures of the slow-wave structure 100 in the stacking direction, which is conducive to simplifying the setting method of the input coupler 30 and the output coupler 40 and improving the integration of the input coupler 30 and the output coupler 40.

[0104] The couplers 50 at the intervals are all coplanar with the first plane 26, so that the setting directions of the couplers 50 at the intervals are all parallel to the first plane 26, which is conducive to providing space for the setting of the attenuator 60. Compared with the couplers 50 at the intervals being not coplanar with the first plane 26, when the attenuator 60 and the coupler 50 at the intervals that are coplanar with the first plane 26 are electrically connected, the attenuator 60 and the coupler 50 at the intervals occupy less space in the first direction, which is conducive to the miniaturization of the slow-wave structure 100.

[0105] For example, referring to Figure 8, the input coupler 30 and the output coupler 40 are both perpendicular to the first plane 26, the couplers 50 at the two intervals are both parallel to the first plane 26, and the setting direction of the coupler 50 at the interval and the attenuator 60 electrically connected thereto is parallel to the first plane 26, which is conducive to making full use of the space of the slow-wave structure 100 parallel to the first plane 26, reducing the space occupied by the attenuator 60 and the coupler 50 at the interval in the first direction, and realizing the miniaturization of the slow-wave structure 100.

[0106] The spacer coupler 50 includes a third mode converter 55, a spacer coaxial line 56, and a fourth waveguide. The third mode converter 55 includes multiple third metal parts 551, which are connected in sequence. Adjacent third metal parts 551 form a stepped structure. The arrangement direction of the multiple third metal parts 551 is parallel to the first plane 26. The spacer coaxial line 56 is electrically connected to the slow-wave transmission line 20 and the third mode converter 55. The spacer coaxial line 56 can be electrically connected to the slow-wave transmission line 20 and the third mode converter 55 at both ends. The spacer coaxial line 56 is electrically connected to the multiple third metal parts 551. The spacer coaxial line 56 can be directly connected to a single third metal part 551 located at the end of the multiple third metal parts 551. The spacer coaxial line 56 can extend along a third direction. The multiple third metal parts 551 and at least a portion of the spacer coaxial line 56 are located within the fourth waveguide. The fourth waveguide is used to couple electromagnetic waves so that the partially amplified electromagnetic waves are absorbed by the attenuator 60.

[0107] In one possible embodiment, as shown in Figures 8 and 9 , the slow-wave transmission line 20 includes at least two repeating units, and a single-segment transmission line includes at least one repeating unit, such that the single-segment transmission line includes at least one period. In other words, the number of periods in the single-segment transmission line is equal to the number of repeating units in the single-segment transmission line. The multiple repeating units are connected end-to-end in a second direction (the Y direction in Figures 8 and 9 ). The minimum length of a single repeating unit in the second direction is the length of one period. In other words, the period length of the single-segment transmission line is the minimum length of a single repeating unit in the single-segment transmission line in the second direction.

[0108] The slow-wave transmission line 20 includes at least two sections of transmission lines, and at least one of the number of periods and the period length of the at least two sections of transmission lines is different, so that the reduction rate of the phase velocity of the electromagnetic wave at each section of the transmission line is different, which is beneficial to improving the amplification effect of the slow-wave structure 100 on the electromagnetic wave.

[0109] Exemplarily, referring to FIG8 , the slow-wave transmission line 20 includes a first transmission line 21 and a second transmission line 22 , wherein the period length of the first transmission line 21 is the same as the period length of the second transmission line 22 , and the number of periods of the first transmission line 21 is smaller than the number of periods of the second transmission line 22 , such that the length of the first transmission line 21 in the second direction is smaller than the length of the second transmission line 22 in the second direction.

[0110] In one embodiment, the repeating unit of the slow-wave transmission line 20 is a curved line, and at least two curved lines have the same shape and size. The shape of the at least two curved lines includes but is not limited to U-shape, V-shape or S-shape.

[0111] In one possible embodiment, as shown in Figures 7, 8, and 9, the attenuator 60 is wedge-shaped. The cross-sectional area of ​​the attenuator 60 on the side closer to the coupler 50 at the gap is larger than the cross-sectional area on the side farther from the coupler 50 at the gap. The cross-sectional area is perpendicular to the direction from the coupler 50 at the gap to the attenuator 60. The wedge-shaped attenuator 60 helps reduce the reflection of electromagnetic waves in the attenuator 60, allowing the attenuator 60 to absorb electromagnetic waves with a wider frequency range and power.

[0112] Exemplarily, the direction from the coupler 50 at the gap to the attenuator 60 is parallel to the second direction, and the cross-sectional area of ​​the side of the attenuator 60 close to the coupler 50 at the gap in the direction perpendicular to the second direction is larger than the cross-sectional area of ​​the side of the attenuator 60 away from the coupler 50 at the gap in the direction perpendicular to the second direction, so that the extension direction of the attenuator 60 is parallel to the extension direction of the slow-wave transmission line 20, which is conducive to making full use of the space of the slow-wave structure 100 and realizing the miniaturization of the slow-wave structure 100.

[0113] In one possible embodiment, referring to Figures 2, 3, and 4, the first housing 11 includes a first accommodating cavity 114, a second accommodating cavity 115, and a third accommodating cavity 116 that are interconnected. The first accommodating cavity 114 is the chamber of the first waveguide 13 and is used to accommodate the slow-wave transmission line 20 and pass electrons. The first accommodating cavity 114 can constitute the chamber of the first waveguide 13, with the first housing 11 alone constituting the first waveguide 13, so that the slow-wave transmission line 20 is integrated only with the first housing 11. Alternatively, the first housing 11 and the second housing 12 can jointly enclose the chamber of the first waveguide 13, and the first housing 11 and the second housing 12 jointly constitute the second waveguide 33, so that the slow-wave transmission line 20 is integrated with both the first housing 11 and the second housing 12.

[0114] The second accommodating cavity 115 and the third accommodating cavity 116 are both connected to the first accommodating cavity 114. The second accommodating cavity 115 constitutes a cavity for the second waveguide 33. The first shell cover 11 constitutes the second waveguide 33. The second accommodating cavity 115 is used to accommodate multiple first metal parts 311. The input coaxial line 32 is located at the connection point between the second accommodating cavity 115 and the first accommodating cavity 114, so that one end of the input coaxial line 32 electrically connected to the multiple first metal parts 311 is located in the second accommodating cavity 115, and one end of the input coaxial line 32 electrically connected to the slow-wave transmission line 20 is located in the first accommodating cavity 114. The third accommodating cavity 116 constitutes a cavity of the third waveguide 43, the first shell cover 11 constitutes the third waveguide 43, the third accommodating cavity 116 is used to accommodate multiple second metal parts 411, and the output coaxial line 42 is located at the connection point between the third accommodating cavity 116 and the first accommodating cavity 114, so that one end of the output coaxial line 42 electrically connected to the multiple second metal parts 411 is located in the third accommodating cavity 116, and one end of the output coaxial line 42 electrically connected to the slow-wave transmission line 20 is located in the first accommodating cavity 114.

[0115] By configuring the first housing 11 to form the second waveguide 33 and the third waveguide 43, the input coupler 30 and the output coupler 40 can be integrated with the first housing 11. When the first housing 11 and the second housing 12 are assembled in the stacking direction, the input coupler 30 and the output coupler 40 can be simultaneously integrated with the slow-wave structure 100, facilitating assembly of the input coupler 30 and the output coupler 40 in the stacking direction and simplifying the configuration of the input coupler 30 and the output coupler 40. Furthermore, compared to separately configuring the housing structure to form the second waveguide 33 and the third waveguide 43 and then integrating them with the first housing 11, the number of components in the slow-wave structure 100 is reduced, the integration level of the input coupler 30 and the output coupler 40 is improved, and miniaturization of the slow-wave structure 100 is achieved.

[0116] In one embodiment, referring to FIG. 7 , the attenuator 60 is electrically connected to the output coupler 40 , and the attenuator 60 electrically connected to the output coupler 40 is accommodated in the third accommodation cavity 116 , which is beneficial to improving the integration of the attenuator 60 and the output coupler 40 .

[0117] In one embodiment, please refer to Figure 8, the first shell cover 11 also includes a fourth accommodating cavity, which is connected to the first accommodating cavity 114, and the fourth accommodating cavity constitutes a cavity of the fourth waveguide. The first shell cover 11 constitutes the fourth waveguide, and the fourth accommodating cavity is used to accommodate multiple third metal parts 551 and the attenuator 60. The coaxial line 56 at the interval is located at the connection between the fourth accommodating cavity and the first accommodating cavity 114, so that one end of the coaxial line 56 at the interval that is electrically connected to the multiple third metal parts 551 is located in the fourth accommodating cavity, and one end of the coaxial line 56 at the interval that is electrically connected to the slow-wave transmission line 20 is located in the first accommodating cavity 114.

[0118] By making the first shell 11 form the fourth waveguide, it is convenient to integrate the coupler 50 and attenuator 60 at the gap with the first shell 11. When the first shell 11 and the second shell 12 are assembled in the stacking direction, the integration of the coupler 50 at the gap with the slow-wave structure 100 can be achieved simultaneously, and an accommodation space is provided for the installation of the attenuator 60, which is convenient for assembling the coupler 50 and attenuator 60 at the gap in the stacking direction and simplifying the installation method of the coupler 50 and attenuator 60 at the gap. At the same time, the number of structures in the slow-wave structure 100 is reduced, the integration level of the coupler 50 and attenuator 60 at the gap is improved, and it is convenient to miniaturize the slow-wave structure 100.

[0119] Exemplarily, the fourth accommodating cavity is located on both sides of the slow-wave transmission line 20 in the second direction, so that the coupler 50 and the attenuator 60 at the interval are located on both sides of the slow-wave transmission line 20 in the second direction, which is conducive to making full use of the edge space of the first shell 10 and realizing the miniaturization of the slow-wave structure 100.

[0120] In one possible embodiment, referring to Figures 10 and 11 , Figure 10 illustrates a schematic structural diagram of a slow-wave structure 100 having an energy transmission window and a reflector, provided in an embodiment of the present application, and Figure 11 illustrates an exploded view of the slow-wave structure 100 provided in the embodiment shown in Figure 10 . A first housing 11 includes a first input aperture 111 and a first output aperture 112, spaced apart from each other. The input coupler 30 is fixedly connected to the inner wall of the first input aperture 111, and the output coupler 40 is fixedly connected to the inner wall of the first output aperture 112. This allows at least a portion of the input coupler 30 and at least a portion of the output coupler 40 to be accommodated within the shell of the first housing 10. This fully utilizes the thickness of the first housing 10 to provide space for the input coupler 30 and the output coupler 40, thereby improving the integration of the input coupler 30 and the output coupler 40 with the first housing 10 and facilitating miniaturization of the slow-wave structure 100.

[0121] The penetration direction of the first input hole 111 and the penetration direction of the first output hole 112 both have an angle with the first plane 26, so that the penetration direction of the first input hole 111 and the penetration direction of the first output hole 112 have good consistency with the stacking direction, which facilitates the implementation of at least one of the input coupler 30 and the output coupler 40 being non-coplanar with the first plane 26, so that at least one of the input coupler 30 and the output coupler 40 can be integrated with other structures of the slow-wave structure 100 in the stacking direction, simplifying the setting method of the input coupler 30 and / or the output coupler 40.

[0122] The slow-wave structure 100 also includes a first energy transmission window 34 and a second energy transmission window. The first energy transmission window 34 seals the first input hole 111, while the second energy transmission window seals the first output hole 112. This seal ensures that the first input hole 111 and the first output hole 112 are sealed, ensuring a hermetic seal within the first waveguide 13 and facilitating the creation of a vacuum environment for electron transmission within the first waveguide 13. The first energy transmission window 34 is located between the input coupler 30 and the opening of the first input hole 111, while the second energy transmission window is located between the output coupler 40 and the opening of the first output hole 112. The first energy transmission window 34 and the second energy transmission window respectively seal the first waveguide 13 at the first input hole 111 and the first output hole 112.

[0123] In one embodiment, the slow-wave structure 100 further includes an input waveguide interface 35 and an output waveguide structure. The input waveguide interface 35 is used to electrically connect the input coupler 30 and the input device 203, and the output waveguide interface 44 is used to electrically connect the output coupler 40 and the output device 204. The input waveguide interface 35 is inserted into the first input hole 111 and contacts the first energy transmission window 34. The first energy transmission window 34 is used to electrically connect the input coupler 30 and the input waveguide interface 35, so that electromagnetic waves at the input device 203 can be transmitted to the input coupler 30 through the first energy transmission window 34. The output waveguide interface 44 is inserted into the second output hole 122 and contacts the second energy transmission window. The second energy transmission window is used to electrically connect the output coupler 40 and the output waveguide, so that electromagnetic waves at the output coupler 40 can be transmitted to the output device 204 through the second energy transmission window.

[0124] In one embodiment, referring to Figures 12 and 13, Figure 12 shows a perspective structural diagram of the inner wall of the first input hole 111 and the first energy transmission window 34 provided in an embodiment of the present application, and Figure 13 shows an exploded view of the inner wall of the first input hole 111 and the first energy transmission window 34 provided in the embodiment shown in Figure 12. At least one of the inner wall of the first input hole 111 and the first output hole 112 may have a flange 113. Specifically, the inner wall of the first input hole 111 and the inner wall of the first output hole 112 may both have flanges 113, or the inner wall of the first input hole 111 may have flanges 113 while the inner wall of the first output hole 112 may not have flanges 113, or the inner wall of the first input hole 111 may not have flanges 113 while the inner wall of the first output hole 112 may have flanges 113.

[0125] The flange 113 supports and connects at least one of the first energy transmission window 34 and the second energy transmission window, so that the setting position of the first energy transmission window 34 and / or the second energy transmission window in the slow-wave structure 100 is more stable, ensuring the closure of the first input hole 111 by the first energy transmission window 34 and the closure of the first output hole 112 by the second energy transmission window, which is conducive to maintaining the first waveguide 13 in a sealed state.

[0126] The inner wall of the first input hole 111 can include at least two flanges 113, spaced apart in the first direction so that the first energy transmission window 34 is sandwiched between the at least two flanges 113. The at least two flanges 113 limit the position of the first energy transmission window 34 in the first direction. The inner wall of the first input hole 111 limits the position of the first energy transmission window 34 perpendicular to the first direction, further enhancing the positional stability of the first energy transmission window 34. Similarly, the inner wall of the first output hole 112 can also include at least two flanges 113, spaced apart in the first direction so that the second energy transmission window is sandwiched between the multiple flanges 113, further enhancing the positional stability of the second energy transmission window. The flanges 113 can be arranged around a central axis parallel to the first direction. The flanges 113 can be annular or comprise multiple spaced apart flanges 113, each of which is arranged around the central axis.

[0127] 11 , the second housing cover 12 has a second input hole 121 and a second output hole 122. The second input hole 121 and the second output hole 122 are spaced apart. The first input hole 111 and the second input hole 121 intersect with each other in the first direction, i.e., the orthographic projections of the area enclosed by the inner wall of the first input hole 111 on the area enclosed by the inner wall of the second input hole 121 at least partially overlap. The first output hole 112 and the second output hole 122 intersect with each other in the first direction, i.e., the orthographic projections of the area enclosed by the inner wall of the first output hole 112 on the area enclosed by the inner wall of the second output hole 122 at least partially overlap.

[0128] The slow-wave structure 100 further includes a first reflector 36 and a second reflector 45. The first reflector 36 seals the second input hole 121, and the second reflector 45 seals the second output hole 122. This ensures that the second input hole 121 and the second output hole 122 are sealed, ensuring a sealed state within the first waveguide 13 and facilitating a vacuum environment for electron transmission within the first waveguide 13. The first reflector 36 is positioned between the input coupler 30 and the opening of the second input hole 121, and the second reflector 45 is positioned between the output coupler 40 and the opening of the second output hole. The first reflector 36 and the second reflector 45 respectively seal the first waveguide 13 at the second input hole 121 and the second output hole 122. The first reflector 36 can be fixedly connected to the inner wall of the second input hole 121, and the second reflector 45 can be fixedly connected to the inner wall of the second output hole 122, so that the first reflector 36 and the second reflector 45 are accommodated in the shell layer of the second shell 10, and the thickness of the second shell 10 is fully utilized to provide accommodation space for the first reflector 36 and the second reflector 45, which is conducive to the miniaturization of the slow-wave structure 100.

[0129] The first reflector 36 is used to make the electromagnetic wave transmitted to the first reflector 36 cancel out its phase with the original electromagnetic wave after reflection, and the second reflector 45 is used to make the electromagnetic wave transmitted to the second reflector 45 cancel out its phase with the original electromagnetic wave after reflection, which is beneficial to improving the stability of the electromagnetic wave during transmission.

[0130] In one embodiment, referring to Figures 10 and 11, one of the first shell cover 11 and the second shell cover 12 includes a circuit layer 14. The circuit layer 14 may belong to the first shell cover 11 or the second shell cover 12. The circuit layer 14 is stacked and connected to the other of the first shell cover 11 and the second shell cover 12 in a first direction. The slow-wave transmission line 20 is provided on the circuit layer 14. The slow-wave transmission line 20 is fixedly connected to the inner wall of the shell 10 at the circuit layer 14, so that the slow-wave transmission line 20 can be integrated with other structures of the slow-wave structure 100 in the stacking direction, simplifying the arrangement of the slow-wave transmission line 20 and making the assembly of the slow-wave transmission line 20 more convenient for industrial production. At the same time, the integration of the slow-wave transmission line 20 with the first shell cover 11 or the second shell cover 12 improves the integration of the slow-wave transmission line 20 with the shell 10, which is conducive to the miniaturization of the slow-wave structure 100.

[0131] The circuit layer 14 may include an upper tube shell 142, a slow-wave transmission line layer 141 and a lower tube shell 143. The slow-wave transmission line layer 141 is sandwiched between the upper tube shell 142 and the lower tube shell 143. The slow-wave transmission line layer 141 has a slow-wave transmission line 20 accommodating hole that is conductive in the first direction. The slow-wave transmission line 20 is arranged in the slow-wave transmission line 20 accommodating hole. The upper tube shell 142 and the lower tube shell 143 respectively close the slow-wave transmission line 20 accommodating hole on both sides of the slow-wave transmission line layer 141 in the first direction to form a first accommodating cavity 114.

[0132] In one embodiment, the first housing 11 may include a coupling layer 15. The coupling layer 15 may include a first coupling layer 151 and a second coupling layer 152. The input coupler 30 is disposed on the first coupling layer 151, and the output coupler 40 is disposed on the second coupling layer 152. The first coupling layer 151, the second coupling layer 152, and the circuit layer 14 may be stacked and connected sequentially in a first direction. The first coupling layer 151 and the second coupling layer 152 may be located on the same plane parallel to the first plane 26. Similarly, the first housing 11 may also include an energy transmission window layer 16. The energy transmission window layer 16 may include a first energy transmission window layer 161 and a second energy transmission window layer 162. The first energy transmission window 34 is disposed on the first energy transmission window layer 161, and the second energy transmission window is disposed on the second energy transmission window layer 162. The first energy transmission window layer 161 , the second energy transmission window layer 162 , the first coupling layer 151 , the second coupling layer 152 and the circuit layer 14 can be stacked and connected in sequence in the first direction, and the first energy transmission window layer 161 and the second energy transmission window layer 162 can be located on the same plane parallel to the first plane 26 .

[0133] In one embodiment, the second housing 12 may include a reflector layer 17, which may include a first reflector layer 171 and a second reflector layer 172. The first reflector 36 is disposed on the first reflector layer 171, and the first reflector 36 is disposed on the second reflector layer 172. The first energy transmission window layer 161, the second energy transmission window layer 162, the first coupling layer 151, the second coupling layer 152, the circuit layer 14, the first reflector layer 171, and the second reflector layer 172 may be stacked and connected in sequence in a first direction. The first reflector layer 171 and the second reflector layer 172 may be located on the same plane parallel to the first plane 26.

[0134] In one possible embodiment, as shown in Figure 4, the slow-wave transmission line 20 is parallel to the first plane 26, the number of the slow-wave transmission lines 20 is at least two, and at least two slow-wave transmission lines 20 are stacked at intervals in the first direction. At least two slow-wave transmission lines 20 are used to transmit electromagnetic waves, which is conducive to generating an electric field with consistent direction and enhancing the amplification effect of the slow-wave structure 100 on electromagnetic waves.

[0135] In one possible embodiment, referring to Figure 1, the materials of the slow-wave transmission line 20, the input coupler 30, the output coupler 40 and the shell 10 include at least one of molybdenum, tungsten, tungsten / molybdenum alloy copper, stainless steel, nickel-based alloy and copper, so that the materials of the slow-wave transmission line 20, the input coupler 30, the output coupler 40 and the shell 10 are all metal.

[0136] The slow-wave structure 100 can use a dielectric support rod to support the slow-wave transmission line 20, or it can achieve the same effect as the dielectric support rod on the slow-wave transmission line 20 by setting the structure of the slow-wave transmission line 20 so that the metal shell 10 can connect and support the slow-wave transmission line 20.

[0137] In one embodiment, as shown in FIG4 , a slow-wave transmission line 20 includes a main transmission line 24 and a plurality of branches 25. The main transmission line 24 extends along a second direction, and an input coupler 30 and an output coupler 40 are electrically connected to both ends of the main transmission line 24. One end of each of the plurality of branches 25 is electrically connected to the main transmission line 24, and the other end is connected to the inner wall of the housing 10. The plurality of branches 25 are spaced apart in the second direction, and the housing 10 supports the plurality of branches 25, so that the slow-wave transmission line 20 is supported by the housing 10. When the slow-wave transmission line 20 transmits high-frequency electromagnetic waves, the high-frequency electromagnetic waves are effectively disconnected at the plurality of branches 25, preventing the high-frequency electromagnetic waves from being transmitted from the plurality of branches 25 to the housing 10, causing the mode of the slow-wave structure 100 to be a TEM mode or a quasi-TEM mode. The above-mentioned setting method reduces the number of structures of the slow-wave structure 100, so that the material of each structure of the slow-wave structure 100 is metal, which is conducive to simplifying the processing of the slow-wave structure 100, improving the integration of each structure in the slow-wave structure 100, and realizing the miniaturization of the slow-wave structure 100.

[0138] The present application also provides a traveling wave tube 200, as shown in FIG14 , which shows a schematic structural diagram of the traveling wave tube 200 provided in an embodiment of the present application. The traveling wave tube 200 includes an electron gun 201, a collector 202, an input device 203, an output device 204, and the slow-wave structure 100 described in any of the above embodiments. The electron gun 201 and the collector 202 are both fixedly connected to the housing 10 of the slow-wave structure 100. The electron gun 201 is used to emit electrons into the first waveguide 13 of the slow-wave structure 100. The collector 202 is used to collect electrons in the first waveguide 13. The input device 203 is electrically connected to the input coupler 30 of the slow-wave structure 100 and is used to transmit electromagnetic waves to the input coupler 30. The output device 204 is electrically connected to the output coupler 40 of the slow-wave structure 100 and is used to transmit amplified electromagnetic waves to the output device 204.

[0139] In one embodiment, the electron gun 201 and the collector 202 are respectively located on either side of the slow-wave structure 100 in the second direction (the Y direction in FIG. 14 ). Electrons travel along the second direction from the electron gun 201 through the slow-wave structure 100 to the collector 202. The input device 203 and the output device 204 are respectively located on either side of the slow-wave structure 100 in the third direction (the X direction in FIG. 14 ).

[0140] In one embodiment, the traveling wave tube 200 further includes a focusing system 205, which is used to constrain the magnetic field within the first waveguide 13 of the slow-wave structure 100 so that the electron beam emitted by the electron gun 201 passes through the slow-wave structure 100 without interception, thereby improving the amplification effect of the traveling wave tube 200 on electromagnetic waves.

[0141] In one embodiment, as shown in FIG. 1 , the housing 10 has an electron emission hole 117 . The electron gun 201 corresponds to the electron emission hole 117 and emits electrons from the electron emission hole 117 into the first waveguide 13 . The electron gun 201 is connected to the housing 10 and closes the electron emission hole 117 .

[0142] It can be understood that the traveling wave tube 200 in this embodiment has the slow-wave structure 100 in the above embodiment. Therefore, the traveling wave tube 200 in this embodiment has all the technical effects of the slow-wave structure 100 in the above embodiment. Since the technical effects of the slow-wave structure 100 have been fully explained in the above embodiment, they will not be repeated here.

[0143] The present application also provides a network device 300, as shown in Figure 15 , which shows a system diagram of the network device 300 provided in an embodiment of the present application. The network device 300 includes an antenna 301 and the aforementioned traveling wave tube 200. The antenna 301 is electrically connected to the traveling wave tube 200 and is used to transmit the electromagnetic waves amplified by the traveling wave tube 200.

[0144] It can be understood that the network device 300 in this embodiment has the traveling wave tube 200 in the above embodiment. Therefore, the network device 300 in this embodiment has all the technical effects of the traveling wave tube 200 in the above embodiment. Since the technical effects of the traveling wave tube 200 have been fully explained in the above embodiment, they will not be repeated here.

[0145] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present application, and should all be included in the scope of protection of the present application.

Claims

1. A slow-wave structure, characterized in that: include: The housing comprises a first housing cover and a second housing cover which are stacked and connected along a first direction; A slow-wave transmission line extends along a first plane perpendicular to the first direction, and the slow-wave transmission line is fixed in a first waveguide formed by the first shell cover and the second shell cover; The input coupler and the output coupler are both electrically connected to the slow-wave transmission line, and at least one of the input coupler and the output coupler is not coplanar with the first plane.

2. The slow-wave structure according to claim 1, characterized in that: The input coupler includes a plurality of first metal parts connected in sequence, and the output coupler includes a plurality of second metal parts connected in sequence, two adjacent first metal parts or two adjacent second metal parts form a step structure, and at least one of the arrangement directions of the plurality of first metal parts and the arrangement directions of the plurality of second metal parts has an angle with the first plane.

3. The slow-wave structure according to claim 2, characterized in that: The input coupler also includes an input coaxial line and a second waveguide, wherein the input coaxial line is electrically connected to the slow-wave transmission line and the first metal parts, the first metal parts and at least part of the input coaxial line are located in the second waveguide, and the second waveguide is used for coupling electromagnetic waves.

4. The slow-wave structure according to any one of claims 1 to 3, characterized in that: It also includes at least one attenuator, which is electrically connected to the output coupler or the input coupler, and is used to absorb electromagnetic waves.

5. The slow-wave structure according to any one of claims 1 to 4, characterized in that: The slow-wave transmission line comprises at least two sections of transmission line, two adjacent sections of the at least two sections of transmission line are arranged at intervals, each section of the transmission line is electrically connected to at least one attenuator, and the transmission line and the at least one attenuator are electrically connected to a coupler located at the interval.

6. The slow-wave structure according to claim 5, characterized in that: The input coupler and the output coupler are not coplanar with the first plane, and the couplers at the intervals are coplanar with the first plane.

7. The slow-wave structure according to any one of claims 5 or 6, characterized in that: At least two sections of the transmission line differ in at least one of the number of periods and the length of periods.

8. The slow-wave structure according to any one of claims 1 to 7, characterized in that: The attenuator is in a wedge shape.

9. The slow-wave structure according to any one of claims 5 to 8, characterized in that: The cross-sectional area of ​​the attenuator at a side close to the coupler at the interval is larger than the cross-sectional area of ​​the attenuator at a side far from the coupler at the interval, and the cross-sectional area is perpendicular to the direction from the coupler at the interval to the attenuator.

10. The slow-wave structure according to any one of claims 4 to 9, characterized in that: The attenuator, the input coupler, and the output coupler are all integrated with the first housing cover.

11. The slow-wave structure according to any one of claims 1 to 10, characterized in that: The first shell cover has a first input hole and a first output hole. The input coupler is fixedly connected to the inner wall of the first input hole, and the output coupler is fixedly connected to the inner wall of the first output hole.

12. The slow-wave structure according to claim 11, characterized in that: It also includes a first energy transmission window and a second energy transmission window, the first energy transmission window closes the first input hole, the second energy transmission window closes the first output hole, the first energy transmission window is electrically connected to the input coupler and the input waveguide interface, and the second energy transmission window is electrically connected to the output coupler and the output waveguide interface.

13. The slow-wave structure according to claim 12, characterized in that: An inner wall of at least one of the first input hole and the first output hole has a flange, and the flange supports and connects at least one of the first energy transmission window and the second energy transmission window.

14. The slow-wave structure according to any one of claims 11 to 13, characterized in that: The second shell cover has a second input hole and a second output hole, the first input hole and the second input hole are intertwined in the first direction, and the first output hole and the second output hole are intertwined in the first direction; the slow-wave structure also includes a first reflector and a second reflector, the first reflector closes the second input hole, and the second reflector closes the second output hole.

15. The slow-wave structure according to any one of claims 1 to 14, characterized in that: One of the first housing cover and the second housing cover includes a circuit layer, and the circuit layer is laminated and connected to the other of the first housing cover and the second housing cover in the first direction.

16. The slow-wave structure according to any one of claims 1 to 15, characterized in that: The slow-wave transmission line is parallel to the first plane, the number of the slow-wave transmission lines is at least two, and at least two slow-wave transmission lines are alternately stacked in the first direction.

17. The slow-wave structure according to any one of claims 1 to 16, characterized in that: The input coupler and the output coupler are located on the same side of the slow-wave transmission line in the first direction.

18. A traveling wave tube, characterized in that: It comprises an electron gun, a collector, a focusing system, an input device, an output device and the slow-wave structure according to any one of claims 1 to 17, wherein the electron gun and the collector are fixedly connected to the shell of the slow-wave structure, the electron gun is used to emit electrons into a first waveguide of the slow-wave structure, the collector is used to collect electrons in the first waveguide, the focusing system is used to allow electrons to pass through the slow-wave structure, the input device is electrically connected to an input coupler of the slow-wave structure, the input device is used to send electromagnetic waves to the input coupler, the output device is electrically connected to an output coupler of the slow-wave structure, and the output coupler is used to send amplified electromagnetic waves to the output device.

19. A network device, characterized in that: It comprises an antenna and the traveling wave tube as claimed in claim 18, wherein the antenna and the traveling wave tube are electrically connected, and the antenna is used to transmit the electromagnetic waves amplified by the traveling wave tube.

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