A waveguide energy transmission window capable of suppressing ghost mode oscillation and a manufacturing method thereof

Abstract

The present invention discloses a waveguide energy transmission window capable of suppressing spurious mode oscillation and a manufacturing method thereof. The waveguide energy transmission window includes: a first rectangular waveguide section, a second rectangular waveguide section coaxially arranged therewith, and a circular waveguide section located therebetween, as well as a circular ceramic sheet hermetically arranged in the circular waveguide section. The long sides of the first rectangular waveguide section and the second rectangular waveguide section are parallel. A linear conductor is formed on the circular ceramic sheet along the diameter, and the linear conductor is arranged parallel to the long side of the rectangular waveguide section. The technical solution of the present invention enables the microwave axially passing through the circular waveguide section to be converted from the circular waveguide into two semi-circular waveguides for propagation, so that the electric field direction of the microwave in the circular waveguide is perpendicular to the waveguide wall direction, thereby suppressing the coexisting mode generated during the conversion of the microwave in waveguides of different shapes, and further suppressing the spurious parasitic oscillation of the microwave generated during this process; at the same time, the energy loss of the microwave when passing through the circular energy transmission window is greatly reduced, and the energy transmission efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the field of vacuum electronic devices. More specifically, it relates to a waveguide energy transmission window capable of suppressing ghost mode oscillation and a manufacturing method thereof. Background Art

[0002] In the prior art, a microwave transmission between the inside and the outside of a vacuum electronic device is achieved through an energy transmission window component. The microwave energy transmission window is an important part of a high-power vacuum microwave tube, and its quality directly affects the stability and working life of the microwave tube. At present, since a circular ceramic sheet is simple to process as an insulating window sheet and is easy to seal, a cylindrical waveguide energy transmission window is widely used. The window sheet of the waveguide energy transmission window often uses a circular ceramic sheet, and the ceramic sheet material generally uses insulating materials such as alumina ceramic, beryllia ceramic, ruby, and sapphire.

[0003] For a cylindrical waveguide energy transmission window, when microwave passes through the cylindrical waveguide energy transmission window, it first converts from the main mode □TE10 mode of a rectangular waveguide to the main mode 〇TE11 mode of a circular waveguide, and then changes back to the main mode □TE10 mode of the rectangular waveguide, experiencing two conversions during this period. In this conversion process of rectangular waveguide - circular waveguide - rectangular waveguide, if the polarization direction of the microwave deflects in the circular waveguide, at the junction of the circular waveguide and the rectangular waveguide, due to the change of the transmission line boundary, the main mode 〇TE11 will decompose into other multiple modes at the boundary. And if the balance of the electric field perpendicular to the waveguide wall is to be re - achieved, in addition to the main mode □TE10 mode that enters the rectangular waveguide and continues to propagate, other symbiotic modes will also be caused. Some of these symbiotic modes will generate reflections. If the degree is reduced, they will be attenuated. If the degree is larger, the microwave will propagate back and forth at the two circular - straight junctions (the junction of the circular waveguide and the rectangular waveguide), generating ghost mode oscillation. Therefore, the cylindrical waveguide energy transmission window is extremely prone to generate ghost mode parasitic oscillation during the microwave transmission process, which is a huge safety hazard to the microwave tube. In the above - mentioned process of the two conversions, a large amount of energy loss is also generated.

[0004] Therefore, a new waveguide energy transmission window capable of suppressing ghost mode oscillation and a manufacturing method thereof are needed. Summary of the Invention

[0005] The purpose of the present invention is to provide a waveguide energy transmission window capable of suppressing ghost mode oscillation to solve at least one of the problems existing in the prior art;

[0006] To achieve the above - mentioned purpose, the present invention adopts the following technical solutions:

[0007] The first embodiment of the present invention provides a waveguide energy transmission window capable of suppressing ghost mode oscillation, including:

[0008] A first rectangular waveguide section, a second rectangular waveguide section coaxially arranged with each other and a circular waveguide section located therebetween, and

[0009] A circular ceramic sheet hermetically disposed in a circular waveguide section, characterized in that

[0010] A linear conductor is formed on the circular ceramic sheet along the diameter, and the linear conductor is arranged parallel to the long side of the rectangular waveguide section.

[0011] Furthermore, the linear conductor penetrates the diameter of the circular ceramic sheet, and both ends of the linear conductor extend to the edges of the side wall of the circular ceramic sheet.

[0012] Furthermore, the linear conductor is located on the surface of the circular ceramic sheet facing the first rectangular waveguide section.

[0013] Furthermore, in the direction perpendicular to the diameter on the horizontal plane where the surface of the circular ceramic sheet is located, the length of the linear conductor does not exceed 1 / 30 of the diameter of the circular ceramic sheet.

[0014] Furthermore, the linear conductor is formed by a coating layer coated on the surface of the circular ceramic sheet and an electroplated layer covering the surface of the coating layer.

[0015] Furthermore, the thickness of the coating layer does not exceed 0.03 mm, and the thickness of the electroplated layer does not exceed 10 μm.

[0016] Furthermore, the material of the coating layer is one or more of molybdenum, manganese, and silicon dioxide; the material of the electroplated layer is nickel.

[0017] Furthermore, the circular ceramic sheet is provided with a groove for accommodating the linear conductor.

[0018] Furthermore, the groove is a through groove penetrating two opposite surfaces of the circular ceramic sheet, and the through groove forms a first half body and a second half body that are symmetric along the diameter on the circular ceramic sheet; a ceramic metal is provided in the through groove to form the linear conductor.

[0019] Furthermore, the material of the linear conductor is one or more of nickel, oxygen-free copper, and nickel-copper alloy.

[0020] The second embodiment of the present invention provides a method for manufacturing the above-mentioned waveguide energy transmission window, including:

[0021] Stack a coating layer and an electroplated layer in sequence along the diameter of the circular ceramic sheet;

[0022] Fix the outer wall of the circular ceramic sheet and the inner wall of the circular waveguide section to form a sealed inner cavity;

[0023] Fix the first rectangular waveguide section and the second rectangular waveguide section on two opposite circular surfaces of the circular waveguide section in sequence, wherein the linear conductor is arranged parallel to the long side of the rectangular waveguide section.

[0024] The beneficial effects of the present invention are as follows:

[0025] In the technical solution of the present invention, the microwave axially passing through the circular waveguide section is converted from the circular waveguide into two semi-circular waveguides for propagation, so that the electric field direction of the microwave in the circular waveguide is perpendicular to the waveguide wall direction, thereby suppressing the coexisting modes generated during the conversion of the microwave in waveguides of different shapes, and further suppressing the ghost mode parasitic oscillation generated by the microwave during this process; at the same time, the energy loss of the microwave when passing through the circular waveguide energy window is greatly reduced, and the energy transmission efficiency is improved. Description of the Drawings

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0027] Figure 1 Schematic diagram showing the waveguide energy window of the embodiment of the present invention;

[0028] Figure 2 Electric field polarization diagram showing the main propagation mode in the rectangular waveguide section of the waveguide energy window of the embodiment of the present invention;

[0029] Figure 3 Electric field polarization diagram showing the main propagation mode in the circular waveguide section of the existing waveguide energy window;

[0030] Figure 4 Cross-sectional view showing the waveguide energy window of the embodiment of the present invention;

[0031] Figure 5 Schematic diagram showing a specific example of the circular ceramic sheet of the embodiment of the present invention;

[0032] Figure 6 Schematic diagram showing a specific example of the circular ceramic sheet of the embodiment of the present invention;

[0033] Figure 7 Schematic diagram showing a specific example of the circular ceramic sheet of the embodiment of the present invention;

[0034] Figure 8 Schematic diagram of the electric field polarization of the main propagation mode in the circular waveguide section of the waveguide energy window of the embodiment of the present invention;

[0035] Figure 9 Schematic diagram of the voltage standing wave ratio showing the waveguide energy window of the embodiment of the present invention and the existing waveguide energy window;

[0036] Figure 10Schematic diagram of voltage standing wave ratio under different depth grooves of the circular ceramic sheet according to the embodiments of the present invention;

[0037] Figure 11 Schematic diagram showing another specific example of the circular ceramic sheet according to the embodiments of the present invention. Detailed implementation manners

[0038] To more clearly illustrate the present invention, the present invention will be further described below in conjunction with preferred embodiments and the accompanying drawings. Similar components in the drawings are denoted by the same reference numerals. Those skilled in the art should understand that the content specifically described below is illustrative rather than restrictive, and should not be used to limit the protection scope of the present invention.

[0039] From Figure 2 the electric field polarization diagram of the dominant propagation mode in the rectangular waveguide section of the waveguide energy transmission window shown, it can be seen that the dominant mode of microwave propagation in the rectangular waveguide is the □TE10 mode; while as Figure 3 the electric field polarization diagram of the dominant propagation mode of the circular waveguide shown, the dominant mode of the circular waveguide is the 〇TE11 mode. Since microwaves propagate in a waveguide of any shape, the electric field direction is perpendicular to the ideal electric wall (waveguide wall). Similarly, to achieve microwave transmission in a circular waveguide, it is only necessary to keep the electric field direction perpendicular to the waveguide wall. The structure of the circular waveguide is rotationally symmetric, but from Figure 3 it can be seen that the field of the 〇TE11 mode in the circular waveguide is not rotationally symmetric. Therefore, the polarization direction of the 〇TE11 mode in the circular waveguide is prone to rotation during propagation, and this deflection greatly increases the probability of spurious mode parasitic oscillation. In the prior art, the spurious mode oscillation can be reduced by increasing the attenuation. However, using this method will generate a large amount of heat and reduce the transmission efficiency of the waveguide energy transmission window. For this reason, through analysis and calculation and experimental research, the present invention proposes a waveguide energy transmission window capable of suppressing spurious mode oscillation and its manufacturing method to solve the above problems.

[0040] An embodiment of the present invention discloses a waveguide energy transmission window capable of suppressing spurious mode oscillation, as Figure 6 shown, including:

[0041] A first rectangular waveguide section 1, a second rectangular waveguide section 4 coaxially arranged, and a circular waveguide section 3 located therebetween, and

[0042] A circular ceramic sheet 2 hermetically arranged in the circular waveguide section 3,

[0043] A linear conductor is formed on the circular ceramic sheet along the diameter, and the linear conductor is arranged parallel to the long side of the rectangular waveguide section.

[0044] As Figure 1 and Figure 11As shown, in the embodiment of the present invention, the long sides of the first rectangular waveguide section and the second rectangular waveguide section are parallel. A linear conductor 5 parallel to the long side of the first rectangular waveguide section 1 is provided on the diameter of the circular ceramic sheet 2, and the linear conductor 5 is arranged in a long linear shape on Figure 11 the circular ceramic sheet 2 in Figure 11 , which can further suppress the spurious mode parasitic oscillation generated by microwaves during the energy transmission process; at the same time, it greatly reduces the energy loss of microwaves when passing through the circular waveguide energy transmission window, improving the energy transmission efficiency. It should be noted that in practical applications, the linear conductor 5 can be processed and manufactured from a strip-shaped metal conductor with a thickness. That is to say, the linear conductor in the embodiment of the present invention can also be called a "strip conductor", and the linear structure formed on the circular ceramic sheet in the embodiment of the present invention with this name also belongs to the protection scope of the present invention.

[0045] As an energy transmission component of a microwave tube, both the input port and the output port of the waveguide energy transmission window adopt rectangular waveguides. The external waveguide at the output port on one side of the waveguide energy transmission window adopts a standard rectangular waveguide, that is, the first rectangular waveguide section 1, and the internal waveguide at the input port on the other side generally adopts a non-standard rectangular waveguide, that is, the second rectangular waveguide section 2. In this embodiment, a metal linear conductor parallel to the long side of the rectangular waveguide section of the waveguide energy transmission window is added on the circular ceramic sheet sealed in the circular waveguide section of the waveguide energy transmission window. When microwaves pass axially through the circular ceramic sheet of the waveguide energy transmission window, the TE10 mode of the circular waveguide changes to the TE10 mode propagated by two semi-circular waveguides, and then continues to synthesize into one mode. This process makes the microwave electric field direction perpendicular to the waveguide wall direction, thereby suppressing the rotation of the polarization direction of the main propagation mode 〇TE11 mode of the circular waveguide, and further reducing the spurious mode parasitic oscillation.

[0046] The technical solution of the present invention has been simulated through simulation tests, and an electric field polarization schematic diagram of the circular ceramic sheet as shown in Figure 8 has been formed. As shown in Figure 8 the waveguide energy transmission window of the embodiment of the present invention makes the microwave electric field passing through the circular waveguide section of the waveguide energy transmission window symmetric in the y direction circumferentially. While realizing that the structure of the circular waveguide is rotationally symmetric, it also makes the field of the 〇TE11 mode rotationally symmetric circumferentially, so that the polarization direction of the 〇TE11 mode will not rotate or deflect during the propagation process, and the electric field polarization direction of the main mode 〇TE11 is fixed.

[0047] Figure 9 shows a voltage standing wave ratio schematic diagram of the waveguide energy transmission window using the embodiment of the present invention and the existing waveguide energy transmission window. Among them, the VSWR1 curve is the voltage standing wave ratio curve of the waveguide energy transmission window before improvement; the VSWR2 curve is the voltage standing wave ratio curve of the waveguide energy transmission window after improvement in this embodiment. From Figure 9It can be seen that the VSWR1 curve has an obvious singularity near 5.9 GHz, while the VSWR2 curve still has a protrusion near 5.9 GHz, but it has been significantly improved and is not sufficient to generate spurious mode parasitic oscillation. By this method, the coexisting modes generated during the waveguide conversion of different shapes are effectively suppressed, and further, the spurious mode parasitic oscillation generated by the microwave during this process is suppressed; at the same time, the energy loss of the microwave passing through the circular waveguide energy window is greatly reduced, and the energy transmission efficiency is improved.

[0048] In some alternative implementation manners of this embodiment, as Figure 10 shown, the linear conductor penetrates the diameter of the circular ceramic sheet, and both ends of the linear conductor extend to the edges of the side wall of the circular ceramic sheet. Moreover, the linear conductor is centered with respect to the rectangular projection of the port of the first rectangular waveguide 1 on the circular ceramic sheet. In this embodiment, on the basis of the existing circular waveguide section of the waveguide energy window, a linear conductor is added to the circular ceramic sheet. And since the first rectangular waveguide section, the second rectangular waveguide section, and the circular waveguide section located therebetween are coaxially arranged, the linear conductor is centered with respect to the rectangular projection of the port of the first rectangular waveguide 1 and is parallel to the long side of the rectangular projection so as to make the polarization direction of the microwave axially passing through the circular ceramic sheet symmetric, and more effectively reduce the energy loss caused by the polarization direction deflection. In a specific example, the linear conductor penetrates the diameter of the circular ceramic sheet, and both of its ends extend to the edges of the side wall of the circular ceramic sheet to ensure the physical connection between the circular ceramic sheet and the waveguide wall of the circular waveguide section.

[0049] In some alternative implementation manners of this embodiment, as shown in Figure 1, the linear conductor is located on the surface of the circular ceramic sheet 2 facing the first rectangular waveguide section 1.

[0050] In this embodiment, the linear conductor is arranged outside the circular ceramic sheet 2, close to the first rectangular waveguide section 1, so that during the operation of the waveguide energy window, no impurities will evaporate or gas molecules will be released into the microwave tube to maintain the stability inside the microwave tube.

[0051] In some alternative implementation manners of this embodiment, as Figures 5 - 7 shown, in the direction perpendicular to the diameter on the horizontal plane where the surface of the circular ceramic sheet is located, the length (i.e., width) of the linear conductor generally does not exceed 1 / 30 of the diameter of the circular ceramic sheet. In this embodiment, the length of the linear conductor does not exceed 1 / 30 of the diameter of the circular ceramic sheet, which neither affects the various transmission performance parameters of the waveguide energy window nor can effectively reduce the spurious mode oscillation.

[0052] In some alternative implementation manners of this embodiment, as Figure 5As shown, the linear conductor is formed by a coating layer coated on the surface of a circular ceramic sheet and an electroplated layer located on the surface of the coating layer (the electroplated layer is not shown in the figure).

[0053] Wherein, the electroplated layer is located on the surface of the coating layer; and

[0054] The thickness of the coating layer does not exceed 0.03 mm, and the thickness of the electroplated layer does not exceed 10 μm.

[0055] In some optional implementation manners of this embodiment, the material of the coating layer is one or more of molybdenum, manganese, and silicon dioxide; the material of the electroplated layer is nickel.

[0056] In a specific example, on a circular ceramic sheet, a thin layer of metal sealing material (including molybdenum, manganese, silicon dioxide, etc.) is coated along a diameter direction of the circular ceramic sheet as the coating layer and sintered. To ensure that the transmission performance and structural strength of the waveguide energy transmission window are not affected by the coating layer and the electroplated layer, in this embodiment, the width of the coating layer should not exceed 1 / 30 of the diameter, and the thickness should not exceed 0.03 mm. Then, the electroplated layer uses Ni, and the thickness of the Ni coating does not exceed 10 μm.

[0057] In another specific example, a thin groove can be first made along the entire diameter direction of the circular ceramic sheet with a glass cutter or other cutting tools, so as to facilitate the coating of the linear conductor and the subsequent sintered integral structure is relatively firm. Then, a metal sealing material (including molybdenum, manganese, silicon dioxide, etc.) is coated in the groove and sintered at high temperature. The width of the groove should not exceed 1 / 30 of the diameter, and the depth of the groove is not limited, preferably greater than 0.1 mm, but not too deep so as not to affect the structural strength of the circular ceramic sheet and make it easy to break.

[0058] The processing technology of this embodiment can quickly and efficiently coat the linear conductor on the circular ceramic sheet. The processing technology is simple, and the circular ceramic sheet with the attached linear conductor effectively improves the energy transmission efficiency.

[0059] In some optional implementation manners of this embodiment, as Figure 7 shown, the circular ceramic sheet is provided with a groove for accommodating the linear conductor. That is, on the original circular ceramic sheet, a rectangular thin groove is opened along the diameter direction, and a long strip-shaped metal conductor is embedded in the groove as the linear conductor (metal strip) of the embodiment of the present invention. The material is preferably nickel, oxygen-free copper, nickel-copper alloy, etc. The linear conductor is fixed to the circular ceramic sheet by high-temperature sintering or other processes.

[0060] In a specific example, when the thickness of the linear conductor is greater than the depth of the groove, the linear conductor will protrude from the circular ceramic sheet. In this case, the linear conductor is divided into an upper half and a lower half in the thickness direction. The upper half is the protruding part, that is, the part protruding from the circular ceramic sheet, and the lower half is the internal part, that is, the part of the linear conductor embedded in the groove. Since the thickness requirement for the linear conductor is relatively low, even if the thickness dimension of the linear conductor is greater than the depth of the groove, resulting in the existence of the protruding part, it does not affect the actual application effect of the waveguide energy transmission window in the embodiment of the present invention. The ghost mode parasitic oscillation can still be eliminated in this embodiment, greatly reducing the energy loss of microwaves when passing through the circular waveguide energy transmission window and improving the energy transmission efficiency.

[0061] In some optional implementation manners of this embodiment, such as Figure 6 shown, the groove is a through groove penetrating through two opposite surfaces of the circular ceramic sheet, and the through groove divides the circular ceramic sheet into a first half body and a second half body that are symmetric along the diameter; a ceramic metal is provided in the through groove to form the linear conductor.

[0062] In a specific example, such as Figure 10 shows a schematic diagram of the voltage standing wave ratio curve after embedding linear conductors with corresponding thicknesses in grooves with different depths in the embodiment of the present invention. In this example, the thickness of the circular ceramic sheet is 1.35 mm, and the depths of the grooves opened (that is, the thicknesses of the linear conductors, parameter H) are 0.2 mm, 0.5 mm, 0.8 mm, 1.1 mm, and 1.4 mm respectively. When the depth H = 1.4 mm, the groove becomes a through groove penetrating through two opposite surfaces of the circular ceramic sheet, dividing the circular ceramic sheet into two halves along the diameter. From the comparison between FIG. 10 and Figure 9 it can be seen that the groove depth only slightly affects the standing wave parameters of the window and does not generate Figure 9 the ghost mode oscillation with a large change in the parameter VSWR1 in

[0063] In another specific example, such as Figure 6As shown, two symmetric semi-circular ceramic pieces can also be directly used. The straight-side side walls of these two semi-circular ceramic pieces are joined together to form a complete circular ceramic window pane. In this example, the straight-side side walls of the two semi-bodies are respectively coated with ceramic metal. When the two semi-bodies are joined along the diameter of the circular ceramic piece to jointly form the circular ceramic piece, the ceramic metal coated between them forms a linear conductor. In a specific example, the single-side thickness of the coating on the straight-side side wall of each semi-body cannot exceed 0.02 mm, that is, the single-side thickness of the coating of the linear conductor on each semi-body cannot exceed 0.02 mm. After coating, the first semi-body and the second semi-body are joined and welded along the diameter plane into a complete circular ceramic piece. At this time, the ceramic metal between the two semi-bodies forms the linear conductor of this example. In a specific example, only the straight-side side wall of one semi-body can be coated with ceramic metal with a thickness not exceeding 0.04 mm, and the other semi-body does not need to be coated. Then, the two semi-bodies are joined and welded along the straight-side side closed surface to form a complete circular ceramic piece. In another specific example, the coating thickness of the ceramic metal on the straight-side side wall of each semi-body is different. As long as a complete circular ceramic piece is formed by welding, the overall thickness of the ceramic metal between the straight-side side wall of the first semi-body and the straight-side side wall of the second semi-body does not exceed 0.04 mm.

[0064] It should be noted that, in combination with the above embodiments, any method that uses the example of the present invention to add a linear conductor parallel to the long side of the rectangular waveguide in the circular waveguide section of the waveguide energy transmission window to eliminate ghost mode oscillation and improve the efficiency of the waveguide energy transmission window is not limited to the implementation manners of the above examples of the present invention and still falls within the protection scope of the present invention.

[0065] The waveguide energy transmission window proposed in the embodiments of the present invention can be made in the following way:

[0066] First, form as Figures 5 - 7The circular ceramic sheet with a linear conductor is set in any example. A thin layer of metal sealing material (including molybdenum, manganese, silicon dioxide, etc.) can be coated along the diameter direction of the circular ceramic sheet and sintered at high temperature. It is appropriate that the width does not exceed 1 / 30 of the diameter and the thickness does not exceed 0.03 mm. Then, a Ni coating generally not exceeding 10 microns is electroplated. Or a thin groove is made along the diameter direction with a glass cutter or other cutting tools, and a metal sealing material (including molybdenum, manganese, silicon dioxide, etc.) is coated in the groove and sintered at high temperature. The width of the groove does not exceed 1 / 30 of the diameter, and the depth of the groove is not limited, but it is appropriate to be greater than 0.1 mm. Then, Ni is electroplated, and the coating generally does not exceed 10 microns. Or ceramic-metal sealing material is coated on the diameter surfaces of two semi-circular ceramic sheets, and the unilateral thickness of the coating generally does not exceed 0.02 mm, and then they are welded into a whole circular ceramic sheet. Or a rectangular thin groove is opened along the diameter direction of the circular ceramic sheet, and a strip-shaped conductor (made of nickel, oxygen-free copper, nickel-copper alloy, etc.) is embedded in the groove and fixed by high-temperature sintering or other processes. The circular ceramic sheet formed in this step is called a circular ceramic window sheet with a linear conductor. It should be noted that the linear conductor must reach the side wall edge of the circular ceramic sheet to ensure the physical connection between the circular ceramic window sheet and the waveguide wall of the completed waveguide energy transmission window.

[0067] Furthermore, the circumferential outer side wall of the circular ceramic window sheet with a linear conductor is welded to the circumferential inner side wall of the circular waveguide section to achieve air isolation (vacuum).

[0068] Finally, the circular waveguide section, the first rectangular waveguide section, and the second rectangular waveguide section are welded according to the traditional process. The first rectangular waveguide section and the second rectangular waveguide section are welded to the two circular surfaces of the circular waveguide section in sequence, so that the circular waveguide section, the first rectangular waveguide section, and the second rectangular waveguide section are coaxially arranged, and the linear conductor is parallel to the long side of the first rectangular waveguide. The linear conductor is located on the side of the circular ceramic sheet facing the external rectangular waveguide, and it is ensured that there is no air leakage on both sides of the circular ceramic window sheet, forming a new type of waveguide energy transmission window, that is, the waveguide energy transmission window of the present invention.

[0069] As an energy transmission component of a microwave tube, both the input port and the output port of the waveguide energy transmission window adopt rectangular waveguides. The external waveguide of the output port on one side of the waveguide energy transmission window adopts a standard rectangular waveguide, that is, the first rectangular waveguide section 1, and the internal waveguide of the input port on the other side generally adopts a non-standard rectangular waveguide, that is, the second rectangular waveguide section 2. As Figure 4 shown in the sectional view of the waveguide energy transmission window of the embodiment of the present invention, the outer side wall of the circular ceramic sheet 2 is welded to the inner side wall of the circular waveguide section 3 to form the inner cavity of the sealed waveguide energy transmission window and maintain the internal vacuum state to ensure the transmission of microwaves.

[0070] Figure 9The figure shows a schematic diagram of the voltage standing wave ratio of the embodiment of the present invention and the existing waveguide energy transmission window. Among them, the VSWR1 curve is the voltage standing wave ratio curve of the waveguide energy transmission window before improvement; the VSWR2 curve is the voltage standing wave ratio curve of the waveguide energy transmission window after improvement in this embodiment. From Figure 9 It can be seen that the VSWR1 curve has an obvious singularity near 5.9 GHz, while the VSWR2 curve still has a protrusion near 5.9 GHz, but it has been significantly improved and is not sufficient to generate spurious mode parasitic oscillation. Therefore, the technical solution of the present invention adds a linear conductor on the circular ceramic sheet of the traditional cylindrical waveguide energy transmission window, which extends along the diameter of the circular ceramic sheet, is located at the center of the rectangular projection of the external rectangular waveguide port on the circular ceramic sheet, and is parallel to the long side of the rectangular projection, making the structure of the circular waveguide rotationally symmetric and the field of the 〇TE11 mode rotationally symmetric, suppressing the coexisting modes generated during the conversion process, avoiding the rotation of the electric field polarization direction of the microwave propagation in the circular waveguide, thereby suppressing the spurious mode parasitic oscillation, and at the same time greatly reducing the energy loss of the microwave when passing through the waveguide energy transmission window and improving the energy transmission efficiency.

[0071] Corresponding to the waveguide energy transmission window provided in the above embodiment, another embodiment of the present application further provides a method for manufacturing the above waveguide energy transmission window. Since the waveguide energy transmission window manufacturing method provided in the embodiment of the present application corresponds to the waveguide energy transmission windows provided in the above several embodiments, the previous implementation manners are also applicable to the waveguide energy transmission window manufacturing method provided in this embodiment and will not be described in detail in this embodiment.

[0072] The manufacturing method includes:

[0073] Stack a coating layer and an electroplating layer in sequence along the diameter of the circular ceramic sheet;

[0074] Fix the outer wall of the circular ceramic sheet and the inner wall of the circular waveguide section to form a sealed inner cavity;

[0075] Fix the first rectangular waveguide section and the second rectangular waveguide section on two opposite circular surfaces of the circular waveguide section in sequence, wherein the linear conductor is arranged parallel to the long side of the rectangular waveguide section.

[0076] In this embodiment, first, on the circular ceramic sheet, a metal sealing material is coated along any diameter direction of the circular ceramic sheet as the coating layer and sintered, and an electroplating layer is formed on the coating layer. The coating layer and the electroplating layer form the linear conductor of the embodiment of the present invention.

[0077] Further, the circumferential outer wall of the circular ceramic window sheet with the linear conductor formed is welded and fixed to the circumferential inner wall of the circular waveguide section. The circular ceramic window sheet makes the circular waveguide section form two closed inner cavities to achieve air isolation, that is, a vacuum state.

[0078] Weld and fix the first rectangular waveguide section on the circular surface on one side of the circular waveguide section. During the welding process, weld the linear conductor parallel to the long side of the rectangular waveguide section, and weld and fix the second rectangular waveguide section on the circular surface on the other side of the circular waveguide section. Similarly, weld the linear conductor parallel to the long side of the rectangular waveguide section.

[0079] It can be understood that when welding and fixing the two rectangular waveguide sections, the specific steps can be appropriately changed.

[0080] The technical solution of the present invention enables the microwave axially passing through the circular waveguide section to be converted from the circular waveguide to two semi-circular waveguides for propagation, so that the electric field direction of the microwave in the circular waveguide is perpendicular to the waveguide wall direction, thereby suppressing the coexisting mode generated during the conversion of the microwave in waveguides of different shapes, and further suppressing the ghost mode parasitic oscillation generated by the microwave during this process; at the same time, it greatly reduces the energy loss of the microwave when passing through the circular energy transmission window and improves the energy transmission efficiency.

[0081] Obviously, the above-mentioned embodiments of the present invention are only examples for clearly explaining the present invention, rather than limitations on the implementation manners of the present invention. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the implementation manners here. Any obvious changes or modifications derived from the technical solution of the present invention still fall within the protection scope of the present invention.

Claims

1. A waveguide power transmission window capable of suppressing ghost mode oscillation, comprising: A first rectangular waveguide section, a second rectangular waveguide section coaxially arranged, and a circular waveguide section therebetween, and A circular ceramic sheet hermetically arranged in the circular waveguide section, characterized in that A linear conductor is formed on the circular ceramic sheet along the diameter, and the linear conductor is arranged parallel to the long side of the rectangular waveguide section, The linear conductor is located on the surface of the circular ceramic sheet facing the first rectangular waveguide section, In the direction perpendicular to the diameter on the horizontal plane where the surface of the circular ceramic sheet is located, the width of the linear conductor does not exceed 1 / 30 of the diameter of the circular ceramic sheet; The linear conductor is formed by a coating layer coated on the surface of the circular ceramic sheet and an electroplated layer covering the surface of the coating layer. The material of the coating layer is one or more of molybdenum, manganese, and silicon dioxide; the material of the electroplated layer is nickel.

2. The waveguide energy transmission window according to claim 1, wherein The linear conductor penetrates the diameter of the circular ceramic sheet, and both ends of the linear conductor extend to the edges of the side wall of the circular ceramic sheet.

3. The waveguide power transmission window according to claim 1, wherein The circular ceramic sheet is provided with a groove for accommodating the linear conductor.

4. The waveguide power transmission window according to claim 3, characterized in that The groove is a through groove penetrating two opposite surfaces of the circular ceramic sheet, and the through groove forms a first half body and a second half body symmetric along the diameter on the circular ceramic sheet; a ceramic metal is provided in the through groove to form the linear conductor.

5. The waveguide energy transmission window according to claim 4, wherein The material of the linear conductor is one or more of nickel, oxygen-free copper, and nickel-copper alloy.

6. A method for manufacturing a waveguide power transmission window as described in claim 1, characterized in that, Including: The coating layer and the electroplated layer are sequentially stacked along the diameter of the circular ceramic sheet; The outer wall of the circular ceramic sheet and the inner side wall of the circular waveguide section are fixed to form a sealed inner cavity; The first rectangular waveguide section and the second rectangular waveguide section are sequentially fixed on two opposite circular surfaces of the circular waveguide section, wherein the linear conductor is arranged parallel to the long side of the rectangular waveguide section.

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