Energy transmission coupling structure for staggered gate slow wave circuit and design method thereof

Abstract

The invention provides an energy transmission coupling structure used for a staggered gate slow wave circuit and a design method thereof, the energy transmission coupling structure comprises a three-branch waveguide coupling structure, the three-branch waveguide coupling structure comprises a first branch waveguide used for microwave transmission, and a second branch waveguide and a third branch waveguide arranged along an electron beam advancing direction; the ridge load is arranged on the first branch waveguide along the height direction of the three-branch waveguide coupling structure; and the slot load is arranged in the three-branch waveguide intersection area along the height direction of the three-branch waveguide coupling structure. The energy transmission coupling structure can solve the problems that an existing H-face coupling structure is too long in overall length and complex in structure.

Description

Technical Field

[0001] The present invention relates to the technical field of vacuum electronic devices, and more specifically, to an energy transmission coupling structure for a staggered-gate slow-wave circuit and a design method thereof. Background Art

[0002] Millimeter wave / terahertz technology has important application value in future communications, imaging, radar and other fields. The main obstacle restricting its development is the lack of broadband coherent radiation sources with compact structure and moderate power level. The traveling wave tube is a vacuum electronic device that can generate or amplify millimeter wave / terahertz signals. Compared with other types of devices, the traveling wave tube is one of the few devices that has wide bandwidth, high gain, high power capability and compact structure in both millimeter wave and terahertz frequency bands. Traditional traveling wave tube devices are limited by the size co-transition effect - as the frequency increases, the output power decreases with the square of the frequency, which greatly limits the ability of the traveling wave tube to work in the high frequency band. Band electron injection technology is an effective technical way to overcome this problem, and is currently one of the research hotspots in the field of terahertz vacuum electronic devices.

[0003] The staggered grid circuit is an all-metal slow-wave structure suitable for strip electron beams. It has the advantages of large power capacity and wide bandwidth. Its basic structure is as follows Figure 1 Although the staggered grating slow-wave structure has excellent inherent performance, especially bandwidth, in theory, the relative bandwidth can reach 30%, but because its electromagnetic wave transmission path and electron beam transmission path cannot be naturally separated, the input and output coupling structures must be carefully designed in actual devices to achieve effective feeding and extraction of electromagnetic wave signals.

[0004] The existing coupling structure is divided into two types: E-plane and H-plane. The waveguide lead-out direction is along Figure 1 The Y and X directions are shown. Figure 2 and Figure 3They are the most common E-plane and H-plane coupling structures. Each of these two coupling methods has its own advantages and disadvantages. The E-plane coupling structure is relatively simple and compact in axial (Z-direction) length. After matching design, better performance can be achieved. However, its biggest drawback is that the coupling direction conflicts with the plane where the periodic focusing magnetic field is located, resulting in the output waveguide needing to pass vertically through the magnetic field system for extraction. This brings great difficulties to the design and debugging of the magnetic field system. Especially for strip injection devices, the transmission characteristics of the electron beam are very sensitive to magnetic field changes. Therefore, in actual use, the E-plane coupling structure is generally not used. In the H-plane coupling structure, the waveguide extraction direction is parallel to the plane of the magnetic field system, and is extracted from the middle of the upper and lower magnetic field planes, which makes the coupling system and the magnetic field system independent of each other. However, the H-plane coupling structure requires a more complex transition design, including a gradual change at the end of the slow-wave structure, output waveguide matching, and isolator design. In the end, the coupling system that meets the performance requirements is often too long and has a complex structure. Summary of the invention

[0005] In view of the above problems, the present invention provides an energy transmission coupling structure for a staggered-gate slow-wave circuit to solve the problem that the existing H-plane coupling structure has an overall length that is too long and a complex structure.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] The present invention provides an energy transmission coupling structure for a staggered grid slow-wave circuit, comprising:

[0008] A three-branch waveguide coupling structure, wherein the three-branch waveguide coupling structure comprises a first branch waveguide for microwave transmission and a second branch waveguide and a third branch waveguide arranged along a traveling direction of an electron beam;

[0009] A ridge loading is arranged on the first branch waveguide along the height direction of the three-branch waveguide coupling structure; and a groove loading is arranged at the intersection area of ​​the three-branch waveguides along the height direction of the three-branch waveguide coupling structure.

[0010] A preferred solution is that the third branch waveguide and the second branch waveguide are coaxially arranged, and the slot loading is symmetrically arranged about the axis of the third branch waveguide.

[0011] A preferred solution is that the axis of the third branch waveguide is orthogonal to the axis of the first branch waveguide, and the ridge loading is symmetrically arranged about the axis of the first branch waveguide.

[0012] Preferably, the ridge loading is arranged close to the intersection of the three-branch waveguides.

[0013] Preferably, the groove loading and the ridge loading are formed on two opposite sides of the three-branch waveguide coupling structure respectively.

[0014] A preferred solution is that the energy transmission coupling structure is used to directly couple with the slow-wave structure.

[0015] A preferred solution is that the energy transmission coupling structure is an input coupling structure, further comprising a reflector arranged on a branch waveguide on the traveling wave tube electron gun side.

[0016] A preferred solution is that the energy transmission coupling structure is an output coupling structure, further comprising a reflector arranged on a branch waveguide on the collector side of the traveling wave tube.

[0017] The present invention also provides a method for designing an energy transmission coupling structure for a staggered grating slow-wave circuit, the method comprising: designing an initial three-branch waveguide coupling structure, the initial three-branch waveguide coupling structure comprising a first branch waveguide for microwave transmission and a second branch waveguide and a third branch waveguide arranged along the direction of electron beam travel; arranging ridge loading on the first branch waveguide along the height direction of the three-branch waveguide coupling structure; and arranging groove loading in the intersection area of ​​the three-branch waveguides along the height direction of the three-branch waveguide coupling structure.

[0018] A preferred solution is to adjust the resonant frequency of the energy transmission coupling structure by changing the height of the ridge loading or the depth of the groove loading, thereby optimizing the matching and isolation performance of the energy transmission coupling structure.

[0019] The beneficial effects of the present invention are:

[0020] The overall structure of the energy transmission coupling structure of the present invention is compact, wherein the slot loading and ridge loading for adjusting the isolation and matching characteristics are both located on the three-branch waveguide coupling structure. Compared with the existing H-plane coupling structure that adopts a multi-section step transition method, the present invention adopts this method of adding circuit components in situ without additionally increasing the length of the coupling circuit, thereby maintaining the compactness of the structure. In addition, since slot loading and ridge loading have complementary electrical properties and good parameter adjustment characteristics, a single-section reflector can be used to meet the performance requirements, thereby further shortening the length of the energy transmission coupling structure. The present invention can achieve matching characteristics better than -20dB in the range of 205GHz to 240GHz, and isolation characteristics better than -15dB, thereby further increasing the operating bandwidth of the energy transmission coupling structure to 35GHz.

[0021] The groove loading and ridge loading of the present invention both have tunable characteristics. By changing the height of the ridge loading or the depth of the groove loading to adjust the resonant frequency of the energy transmission coupling structure, the matching and isolation performance of the energy transmission coupling structure can be optimized. This adds a useful fine-tuning mechanism for practical applications, which can compensate for the deterioration of matching performance caused by the processing, assembly and welding processes. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The specific implementation modes of the present invention are further described in detail below in conjunction with the accompanying drawings.

[0023] Figure 1 It is a schematic diagram of the structure of a conventional staggered-gate slow-wave circuit.

[0024] Figure 2 It is a structural schematic diagram of an existing E-plane coupling structure.

[0025] Figure 3 It is a structural schematic diagram of an existing H-plane coupling structure.

[0026] Figure 4 It is a schematic diagram of the structure of an existing three-branch waveguide coupling structure.

[0027] Figure 5 It is one of the structural schematic diagrams of the energy transmission coupling structure of the present invention.

[0028] Figure 6 This is the second structural schematic diagram of the energy transmission coupling structure of the present invention.

[0029] Figure 7 It is a schematic diagram of the S parameter performance of the energy transmission coupling structure of the present invention.

[0030] Figure 8 It is a curve diagram showing the change of the matching characteristics of the energy transmission coupling structure when the slot loading depth of the present invention changes.

[0031] Fig. 9 1 is a frequency response curve diagram of groove loading and ridge loading of the present invention.

[0032] Figure numerals: 1. first branch waveguide, 2. second branch waveguide, 3. third branch waveguide, 4. ridge loading, 5. groove loading, 6. reflector, 7. intersection area of ​​three-branch waveguides. DETAILED DESCRIPTION

[0033] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention unless otherwise specifically stated.

[0034] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

[0035] Techniques and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the techniques and equipment should be considered part of the specification.

[0036] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0037] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0038] Due to the complex transmission characteristics of strip electron beams and the difficulty of stable long-distance transmission, the design of strip beam traveling wave tubes hopes that the circuit will be as short as possible to minimize electron beam interception. Therefore, an overly long coupling system is undesirable. This is also one of the key issues that researchers have been working to solve in the current development of strip beam traveling wave tubes. In addition, overly complex structures will bring difficulties in processing and implementation. Especially in the terahertz frequency band, the optimal dimensions in the electrical performance design are often difficult to strictly achieve in actual processing, which makes it difficult to highly match the design and actual measurement. Therefore, in terms of structure, the coupler also needs to be as simple as possible.

[0039] In summary, the problems of existing coupling structures can be summarized as follows: 1) The existing E-plane coupling structure design conflicts with the direction of the magnetic field system and is difficult to be used in practice; 2) The existing H-plane coupling structure meets practical requirements, but the structure is too complex and too long. If the transition design is simplified, the performance is often unsatisfactory.

[0040] In order to solve the above problems, the present invention provides an energy transmission coupling structure for a staggered grid slow wave circuit, wherein the energy transmission coupling structure is used to directly couple with the slow wave structure of a traveling wave tube. Figures 1 to 9 As shown, specifically, the energy transmission coupling structure for the staggered grid slow wave circuit includes: a three-branch waveguide coupling structure, the three-branch waveguide coupling structure includes a first branch waveguide 1 for microwave transmission and a second branch waveguide 2 and a third branch waveguide 3 arranged along the direction of electron beam travel, a ridge loading 4 arranged on the first branch waveguide 1 along the height direction of the three-branch waveguide coupling structure, and a slot loading 5 arranged at the intersection area 7 of the three-branch waveguide along the height direction of the three-branch waveguide coupling structure. The height direction of the three-branch waveguide coupling structure refers to the Y direction, the direction of electron beam travel refers to the Z direction, and the X direction is perpendicular to both the Y direction and the Z direction. The overall length of the energy transmission coupling structure is short, the structure is compact, and the performance can meet practical requirements. The energy transmission coupling structure can achieve good matching, reflection and isolation characteristics without using complex transitions, solving the problem that the existing coupling structure cannot simultaneously achieve H-plane extraction, simple and compact structure and excellent performance.

[0041] Figure 4It is a three-branch waveguide coupling structure with a reflector 6. The first port is marked as the electromagnetic wave input or output port, corresponding to the first branch waveguide 1. The second port is the port leading to the slow wave structure, corresponding to the second branch waveguide 2. The third port is the port leading to the traveling wave tube electron gun or collector, corresponding to the third branch waveguide 3. It can be understood that the reflector and the three-branch waveguide coupling structure in the figure are connected cavities. Ideally, it is hoped that the first port and the second port are matched and isolated from the third port. In terms of specific indicators, the reflection characteristics are required: S 11 ,S 22 <-10dB, isolation characteristics: S 31 ,S 32 <-10dB. The above indicators are for the final actual circuit. Considering the errors and characteristic changes during circuit processing, assembly and welding, sufficient margin is required in the design. Therefore, the design requirements are generally: Reflection characteristics: S 11 ,S 22 <-20dB, isolation characteristics: S 31 ,S 32 <-15dB, that is, the reflection characteristic S 11 <-20dB, reflection characteristic S 22 <-20dB. Isolation characteristic S 31 <-15dB, isolation characteristic S 32 <-15dB. However, a simple three-branch waveguide coupling structure cannot meet the above requirements in the natural state only by changing the waveguide size without introducing additional circuit elements. At this time, it is necessary to introduce additional circuit components. In order to achieve the isolation characteristics of the third port, a reflector is added between the third port and the other two ports. The principle of the reflector is to simulate the open-circuit load of the transmission line and form an equivalent electrical boundary at a suitable position to achieve total reflection of the electromagnetic wave signal. This process requires adjusting the structural parameters of the reflector and the distance between the first and second ports. However, a single-stage reflector usually cannot meet the isolation characteristics while taking into account the matching characteristics of the first port and the second port, that is, to ensure as much as possible that the signal from the second port is reflected and transmitted along the first port, and the signal from the first port is reflected and transmitted to the second port. For this reason, the usual practice is to adopt a multi-stage setting, that is, Figure 3 The method of using multiple reflectors (also called Bragg reflectors) shown in the figure increases the circuit length. In order to maintain a compact structure, the present invention adopts the method of adding circuit components in situ, that is, adding circuit components to the three-branch waveguide coupling structure to obtain a dual improvement in matching and isolation effects.

[0042] Furthermore, the compensating circuit elements used in the present invention are slot loading and ridge loading which have complementary electromagnetic characteristics. Figure 5As shown, the third branch waveguide 3 and the second branch waveguide 2 are coaxially arranged, and the axis L2 of the third branch waveguide 3 is orthogonal to the axis L1 of the first branch waveguide 1. The first branch waveguide 1 is formed with a first port, the second branch waveguide 2 is formed with a second port, and the third branch waveguide 3 is formed with a third port. The slot loading 5 is located at the intersection area 7 of the three branch waveguides, and the slot loading 5 is symmetrically arranged about the axis L2 of the third branch waveguide 3. Since the slot loading 5 will increase the cutoff frequency of the waveguide, whether the signal transmitted from the second port or the first port is transmitted to the third port, it will feel the increase of the waveguide cutoff frequency due to the influence of the slot loading 5, thereby enhancing the isolation effect of the third port. The ridge loading 4 is arranged on the first branch waveguide 1, and the ridge loading 4 is symmetrically arranged about the axis L1 of the first branch waveguide 1 and the ridge loading 4 is arranged near the intersection area 7 of the three branch waveguides. Since the ridge loading 4 can reduce the cutoff frequency of the waveguide, the transmission matching characteristics between the first port and the second port can be improved.

[0043] Specifically, the ridge loading 4 is equivalent to adding a matching network on the transmission path from the first port to the three-branch waveguide intersection area 7. The network can add an extra reactance to the three-branch waveguide intersection area 7, offset the loading effect of the three-branch waveguide intersection area 7 itself to a certain extent, and can also change the impedance of the waveguide at the connection between the first port and the three-branch waveguide intersection area 7, so that the impedance matching condition meets the requirements.

[0044] The slot loading 5 has no effect on the impedance of the waveguide connecting the first port and the second port, and its function is to change the equivalent impedance of the three-branch waveguide intersection 7. The slot loading 5 is close to the reflector 6, so it has a certain effect on the third branch waveguide 3. The slot loading 5 can form a weak resonance effect with the reflector 6. In theory, this effect is positive and can make the isolation of the third port better.

[0045] More specifically, the ridge loading 4 is to match the first port and the second port, but the equivalent impedance of the three-branch waveguide intersection area 7 and the equivalent impedance of the matching network are not fixed constants. Their values ​​and whether they are inductive or capacitive (i.e., positive or negative signs) vary with frequency. When a very wide bandwidth is required, for example, more than 30GHz, it is difficult to meet the requirements by relying solely on a ridge loading. At this time, a second loading element needs to be introduced, but another ridge loading cannot be introduced, because when the frequency range is very wide, at some frequencies the capacitance / inductance of the ridge loading is the same as that of the three-branch waveguide intersection area 7. This not only fails to offset the reactance of the three-branch waveguide intersection area 7, but instead superimposes and enhances it. Therefore, it is necessary to introduce a loading element with opposite characteristics to the ridge loading 4, that is, to introduce a slot loading 5 in the three-branch waveguide intersection area 7. The so-called opposite characteristics refer to the opposite frequency response trend. Through Fig. 9 The frequency response curves of slot loading 5 and ridge loading 4 in the frequency band of interest are given. It can be clearly seen that slot loading 5 and ridge loading 4 have an effect on S11 The effects of are opposite, especially at the high frequency end, forming two opposite peaks. Based on this, it can be seen that groove loading 5 can further improve the performance of the high frequency band on the basis of ridge loading 4.

[0046] In a specific embodiment, the width a of the three-branch waveguide of the energy transmission coupling structure of the present invention in the X direction and the height b in the Y direction are 0.78 mm and 0.35 mm respectively, the radius of the ridge loading is 0.208 mm, the height of the ridge loading in the Y direction is 0.0694 mm, the distance between the center of the ridge loading and the intersection area of ​​the three-branch waveguide is 0.185 mm, the radius of the groove loading is 0.3 mm, the depth of the groove loading in the Y direction is 0.35 mm, and the distance between the center of the groove loading and the reflector is 0.73 mm.

[0047] Reference Figure 7 It can be seen that in the range of 205GHz to 240GHz, the matching characteristics S11, S22 <-20dB, and the isolation characteristics S31, S32 <-15dB. It can fully meet practical requirements. In addition, the energy transmission coupling structure with ridge loading and groove loading provided by the present invention has a bandwidth range of 35GHz with performance better than -20dB, from 205GHz to 240GHz, thereby further broadening the working bandwidth of the energy transmission coupling structure, improving the matching characteristics and also having a positive impact on the isolation performance.

[0048] Combination Figure 5 and Figure 6 As shown, the slot loading 5 and the ridge loading 4 can be arranged on opposite sides or the same side of the three-branch waveguide coupling structure. Further, in order to avoid interference between the slot loading 5 and the ridge loading 4 due to machining accuracy when machining the slot loading 5 and the ridge loading 4, the slot loading 5 and the ridge loading 4 are respectively formed on two opposite sides of the three-branch waveguide coupling structure.

[0049] More specifically, the energy transmission coupling structure may be an input coupling structure or an output coupling structure. When the energy transmission coupling structure is an input coupling structure, it further includes a reflector arranged on the branch waveguide on the traveling wave tube electron gun side. When the energy transmission coupling structure is an output coupling structure, it further includes a reflector arranged on the branch waveguide on the traveling wave tube collector side. The horizontal cross-sections of the ridge loading and the groove loading may be circular or may be other shapes respectively, and the present invention does not limit this. In the specific processing and manufacturing, two circuit halves are provided, and a high-speed precision milling machine is used to process the grooves constituting the three-branch waveguide coupling structure on the two circuit halves, and at the same time, a raised circular ridge that meets the design requirements is processed on one of the circuit halves, and then a recessed circular groove that meets the design requirements is processed on the other circuit half, and finally the two circuit halves are clamped and welded into a whole by a mold.

[0050] The present invention also provides a design method for an energy transmission coupling structure of a staggered grating slow-wave circuit, the method comprising: designing an initial three-branch waveguide coupling structure, the initial three-branch waveguide coupling structure comprising a first branch waveguide 1 for microwave transmission and a second branch waveguide 2 and a third branch waveguide 3 arranged along the direction of electron beam travel; arranging a ridge loading 4 on the first branch waveguide 1 along the height direction of the three-branch waveguide coupling structure; and arranging a groove loading 5 in a three-branch waveguide intersection area 7 along the height direction of the three-branch waveguide coupling structure.

[0051] Further, combined with Figure 8 As shown in the figure, dh represents the depth of the slot loading 5 (unit: mm). The present invention can adjust the resonant frequency of the energy transmission coupling structure by changing the height of the ridge loading 4 or the depth of the slot loading 5, and optimize the matching and isolation performance of the energy transmission coupling structure. In the terahertz frequency band, the slot loading is more suitable as a tuning hole and is used in conjunction with a tuning pin for tuning due to its larger size, while the ridge loading is more suitable for direct integrated processing due to its relatively small size to ensure accuracy.

[0052] In summary, the overall structure of the energy transmission coupling structure of the present invention is compact, wherein the slot loading and ridge loading for adjusting the isolation and matching characteristics are both located on the three-branch waveguide coupling structure. Compared with the existing H-plane coupling structure that adopts a multi-section step transition method, the present invention adopts this method of adding circuit components in situ without additionally increasing the length of the coupling circuit, thereby maintaining the compactness of the structure. In addition, since slot loading and ridge loading have complementary electrical properties and good parameter adjustment characteristics, a single-section reflector can be used to meet the performance requirements, thereby further shortening the length of the energy transmission coupling structure. The present invention can achieve matching characteristics better than -20dB in the range of 205GHz to 240GHz, and isolation characteristics better than -15dB, thereby further increasing the operating bandwidth of the energy transmission coupling structure to 35GHz.

[0053] The groove loading and ridge loading of the present invention both have tunable characteristics. By changing the height of the ridge loading or the depth of the groove loading to adjust the resonant frequency of the energy transmission coupling structure, the matching and isolation performance of the energy transmission coupling structure can be optimized. This adds a useful fine-tuning mechanism for practical applications, which can compensate for the deterioration of matching performance caused by the processing, assembly and welding processes.

[0054] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not limitations on the implementation methods of the present invention. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the implementation methods here. All obvious changes or modifications derived from the technical solution of the present invention are still within the protection scope of the present invention.

Claims

1. An energy transmission coupling structure for a staggered grid slow wave circuit, characterized in that: include: A three-branch waveguide coupling structure, wherein the three-branch waveguide coupling structure comprises a first branch waveguide for microwave transmission and a second branch waveguide and a third branch waveguide arranged along a traveling direction of an electron beam; A ridge loading is arranged on the first branch waveguide along the height direction of the three-branch waveguide coupling structure; and a groove loading is arranged at the intersection area of ​​the three-branch waveguides along the height direction of the three-branch waveguide coupling structure.

2. The energy transmission coupling structure for staggered-gate slow-wave circuit according to claim 1, characterized in that: The third branch waveguide and the second branch waveguide are coaxially arranged, and the slot loading is symmetrically arranged about the axis of the third branch waveguide.

3. The energy transmission coupling structure for staggered-gate slow-wave circuit according to claim 1, characterized in that: The axis of the third branch waveguide is arranged orthogonally to the axis of the first branch waveguide, and the ridge loading is arranged symmetrically about the axis of the first branch waveguide.

4. The energy transmission coupling structure for staggered-gate slow-wave circuit according to claim 3, characterized in that: The ridge loading is arranged near the three-branch waveguide intersection region.

5. The energy transmission coupling structure for staggered-gate slow-wave circuit according to claim 1, characterized in that: The groove loading and the ridge loading are respectively formed on two opposite sides of the three-branch waveguide coupling structure.

6. The energy transmission coupling structure for staggered-gate slow-wave circuit according to claim 1, characterized in that: The energy transmission coupling structure is used for direct coupling with the slow wave structure.

7. The energy transmission coupling structure for staggered-gate slow-wave circuit according to claim 1, characterized in that: The energy transmission coupling structure is an input coupling structure, and further comprises a reflector arranged on a branch waveguide at the traveling wave tube electron gun side.

8. The energy transmission coupling structure for staggered-gate slow-wave circuit according to claim 1, characterized in that: The energy transmission coupling structure is an output coupling structure, and further comprises a reflector arranged on a branch waveguide at the collector side of the traveling wave tube.

9. A design method for an energy transmission coupling structure for a staggered grid slow-wave circuit, characterized in that: The method comprises: designing an initial three-branch waveguide coupling structure, wherein the initial three-branch waveguide coupling structure comprises a first branch waveguide for microwave transmission and a second branch waveguide and a third branch waveguide arranged along the traveling direction of an electron beam; arranging a ridge loading on the first branch waveguide along the height direction of the three-branch waveguide coupling structure; and arranging a groove loading at a junction area of ​​the three-branch waveguides along the height direction of the three-branch waveguide coupling structure.

10. The design method according to claim 9, characterized in that: The resonant frequency of the energy transmission coupling structure is adjusted by changing the height of the ridge loading or the depth of the groove loading, thereby optimizing the matching and isolation performance of the energy transmission coupling structure.

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