A compact high-power CTS array antenna loaded with a slow-wave structure

Abstract

The present invention discloses a compact, high-power CTS array antenna loaded with a slow-wave structure, comprising: a mode conversion power distribution network structure, a CTS array cascaded with the mode conversion power distribution network structure, and sealed metal plates on both sides of the CTS array. The mode conversion power distribution network structure comprises a special-shaped waveguide component, a coaxial waveguide component disposed within the special-shaped waveguide component, and a polygonal radial parallel plate waveguide fixedly connected to the coaxial waveguide component. The special-shaped waveguide component comprises multiple curved waveguides and multiple rectangular waveguides, forming a mounting step for accommodating the CTS array. The CTS array comprises a parallel plate waveguide and a CTS assembly on a plate above the parallel plate waveguide. The parallel plate waveguide is provided with a corrugated slow-wave structure along the propagation direction. The sealed metal plates simultaneously connect the mode conversion power distribution network structure and the CTS array. According to the present invention, the problem of grating lobes and high-power feeding caused by excessive spacing between high-power CTS array antenna elements is solved, resulting in a flexible and compact structure.

Description

Technical Field

[0001] The present invention relates to the technical field of antennas, and in particular to a compact high-power CTS array antenna loaded with a slow-wave structure. Background Art

[0002] High power microwave technology is an emerging discipline that combines pulse power technology, electric vacuum technology and plasma physics.

[0003] The development of high-power microwave technology was initially driven by military needs. Through high-power antennas, energy can be concentrated on a target area to disrupt or destroy enemy electronic systems, rapidly and cost-effectively, without causing environmental pollution. Furthermore, in radar ranging, the development of impact radar using high-power microwaves can achieve higher ranging resolution, increase range, and enhance anti-interference capabilities. In microwave energy transmission, high-power microwaves can achieve energy transmission in space. In industry and agriculture, high-power microwaves can also be used for drilling, pest control, and other applications.

[0004] High-power microwave systems consist of high-power microwave sources and high-power antennas. High-power antennas need to have good high-power processing capabilities, so the design method of low-power antennas will no longer be applicable. Antennas with high power capacity and compact structure have become a research hotspot.

[0005] The Continuous Transverse Stub (CTS) array antenna radiates electromagnetic waves by creating transverse slots on a parallel plate waveguide. It has the advantages of high power capacity, compact structure, and easy integration. According to array antenna theory, the unit spacing of the CTS array should be one waveguide wavelength. When the parallel plate waveguide is filled with air or vacuum, the unit spacing is one operating wavelength λ0. At this time, excessive unit spacing can easily lead to grating lobes. In order to suppress grating lobes, it is necessary to shorten the waveguide wavelength λ g , so that λ g ≈0.65~0.78λ0. Due to the low breakdown threshold of the dielectric, the method of shortening the wavelength by filling the dielectric is not applicable in the high power field. Loading an uneven slow-wave structure on the flat metal surface of the parallel plate waveguide will destroy the uniformity of the electric field, resulting in a decrease in power capacity. In order to shorten the waveguide wavelength λ g In order to ensure the high power handling capability of the CTS array antenna while ensuring the high power handling capability of the CTS array antenna, it is necessary to study the parallel plate waveguide slow-wave structure with high power capacity. Summary of the Invention

[0006] In response to the shortcomings of the prior art, the present invention aims to provide a compact, high-power CTS array antenna loaded with a slow-wave structure. This antenna solves the problems of grating lobes and high-power feeding caused by excessive spacing between high-power CTS array antenna elements, and offers a flexible and compact structure. To achieve the above-mentioned objectives and other advantages of the present invention, a compact, high-power CTS array antenna loaded with a slow-wave structure is provided, comprising:

[0007] A mode conversion power distribution network structure, a CTS array cascaded with the mode conversion power distribution network structure, and sealing metal plates on both sides of the CTS array;

[0008] The mode conversion power distribution network structure includes a special-shaped waveguide component, a coaxial waveguide component arranged in the special-shaped waveguide component, and a polygonal radial line parallel plate waveguide fixedly connected to the coaxial waveguide component, wherein the special-shaped waveguide component includes a plurality of curved waveguides and a plurality of rectangular waveguides fixedly connected to the curved waveguides, and a mounting step is formed by the plurality of curved waveguides and the plurality of rectangular waveguides, and the mounting step is used to place a CTS array;

[0009] The coaxial waveguide component includes an outer conductor and an inner conductor disposed in the outer conductor, wherein the outer conductor and the inner conductor are spaced apart, and an upper end portion of the inner conductor extends from an upper end surface of the outer conductor;

[0010] The polygonal radial line parallel plate waveguide includes a lower polygonal annular metal plate fixed to the upper end face of the outer conductor, a metal inclined plate fixed to the upper end face of the inner conductor, an upper polygonal metal plate fixed to the upper end face of the metal inclined plate, and a plurality of metal spacers uniformly fixed between the upper polygonal metal plate and the lower polygonal annular metal plate. The metal spacers divide the area between the metal flat plate and the annular metal plate into a plurality of identical output ports, and the output ports are connected to the interval between the outer conductor and the inner conductor.

[0011] Preferably, the CTS array includes a parallel plate waveguide and a CTS component, the parallel plate waveguide includes an upper plate and a lower plate arranged parallel to the upper plate, and an upper plate slow-wave structure is arranged on the end face of the upper plate facing the lower plate, and a lower plate slow-wave structure is arranged on the end face of the lower plate facing the upper plate.

[0012] Preferably, a CTS component is provided on the upper plate, and the CTS component includes a plurality of first-order CTS branches and a plurality of second-order CTS branches.

[0013] Preferably, the multiple curved waveguides and the multiple rectangular waveguides constitute multiple branches, and the path length of each branch is equal, and the output aperture of each rectangular waveguide is at the same plane and the same height.

[0014] Preferably, the tops of the waveforms of the upper plate slow-wave structure and the lower plate slow-wave structure can be flattened to form flattened tops, or additional ripples can be added between the waveforms of the upper plate slow-wave structure and the lower plate slow-wave structure.

[0015] Preferably, the sealed metal plate connects the mode conversion power distribution network structure and the CTS array at the same time.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] (1) The input port of the present invention is a coaxial waveguide, which can be combined with a high-power microwave source;

[0018] (2) In the mode conversion power distribution network structure of the present invention, the mode conversion from the coaxial waveguide to the rectangular waveguide is realized by a polygonal radial line parallel plate waveguide. The number of sides of the polygon can be set according to actual needs, and the design is flexible.

[0019] (3) In the mode conversion power distribution network structure of the present invention, multiple metal spacers are loaded in the polygonal radial line parallel plate waveguide, which can greatly reduce the coupling between the output ports.

[0020] (4) The present invention designs the width of each unit branch separately, which can reduce the side lobes of the radiation pattern.

[0021] (5) The present invention sets a corrugated slow-wave structure between parallel plate waveguides, which can shorten the waveguide wavelength λ g , which reduces the unit spacing from λ0 to 0.65~0.78λ0, thereby suppressing the grating lobes.

[0022] (6) The corrugated slow-wave structure proposed in the present invention has the characteristic of high power capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A three-dimensional structural diagram of a compact high-power CTS array antenna loaded with a slow-wave structure according to the present invention;

[0024] Figure 2 A three-dimensional structure diagram of a mode conversion power distribution network and a CTS array of a compact high-power CTS array antenna loaded with a slow-wave structure according to the present invention;

[0025] Figure 3 A three-dimensional structural diagram of a mode conversion power distribution network of a compact high-power CTS array antenna loaded with a slow-wave structure according to the present invention;

[0026] Figure 4 It is a front cross-sectional view along the yoz plane of a mode conversion power distribution network of a compact high-power CTS array antenna loaded with a slow-wave structure according to the present invention;

[0027] Figure 5 A front cross-sectional view of a CTS array of a compact high-power CTS array antenna loaded with a slow-wave structure according to the present invention, taken along the xoz plane;

[0028] Figure 6 It is a front cross-sectional view along the xoz plane of a deformed parallel plate waveguide slow-wave structure of a compact high-power CTS array antenna loaded with a slow-wave structure according to the present invention;

[0029] Figure 7 The E-plane and H-plane radiation patterns of the compact high-power CTS array antenna loaded with a slow-wave structure according to the present invention;

[0030] Figure 8 : This is a cross-sectional electric field distribution diagram of the compact high-power CTS array antenna loaded with a slow-wave structure according to the present invention at an input power of 650 MW; DETAILED DESCRIPTION

[0031] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0032] Reference Figure 1-8 , a compact high-power CTS array antenna loaded with a slow-wave structure, comprising:

[0033] The mode conversion power distribution network structure 1, the CTS array 2 cascaded with the mode conversion power distribution network structure 1, and the sealed metal plates 3 on both sides of the CTS array; the mode conversion power distribution network structure 1, the CTS array 2 cascaded with the mode conversion power distribution network structure 1, and the sealed metal plates 3 on both sides of the CTS array are all made of metal materials and have a vacuum structure inside.

[0034] The mode conversion power distribution network structure 1 includes a special-shaped waveguide component, a coaxial waveguide 101 disposed in the special-shaped waveguide component, and a polygonal radial line parallel plate waveguide 102 fixedly connected to the coaxial waveguide component, wherein the special-shaped waveguide component includes a plurality of curved waveguides 103 and a plurality of rectangular waveguides 104 fixedly connected to the curved waveguides 103. A mounting step is formed by the plurality of curved waveguides 103 and the plurality of rectangular waveguides 104, and the mounting step is used to place the CTS array 2;

[0035] The coaxial waveguide component includes an outer conductor 112 and an inner conductor 111 disposed within the outer conductor 112. The outer conductor 112 and the inner conductor 111 are spaced apart, with the upper end of the inner conductor 111 extending from the upper end surface of the outer conductor 112. The radii of both the outer conductor 112 and the inner conductor 111 gradually increase along the transmission direction, thereby improving impedance matching. The inner conductor 111 has a radius of r1 at the input end and r3 at the output end. The outer conductor 112 has a radius of r2 at the input end and r4 at the output end. The radius at the top of the inner conductor 111 is r5. The coaxial waveguide component has a height of H1, and the inner conductor 111 has a height of H2.

[0036] The polygonal radial parallel plate waveguide 102 includes a lower polygonal annular metal plate 122 fixed to the upper end face of the outer conductor 112, a metal slanted plate 124 fixed to the upper end face of the inner conductor 111, an upper polygonal metal plate 121 fixed to the upper end face of the metal slanted plate 124, and a plurality of metal spacers 123 uniformly fixed between the upper polygonal metal plate 121 and the lower polygonal annular metal plate 122. The metal spacers 123 divide the area between the upper polygonal metal plate 121 and the lower polygonal annular metal plate 122 into a plurality of identical output ports, each of which communicates with the area between the outer conductor 112 and the inner conductor 111. The output end of the coaxial waveguide 101 is connected to the polygonal radial parallel plate waveguide 102. The thickness of the lower polygonal annular metal plate 122 and the upper polygonal metal plate 121 is t1. Multiple metal spacers 123 are rotationally symmetric about the central axis of coaxial waveguide 101, each with a thickness of t2. They are placed along polygonal radial lines parallel to the lines connecting the center of plate waveguide 102 and each outer corner. Metal inclined plates 124 are used to improve impedance matching and have a radius of r7 and a height of H3.

[0037] The output aperture of the polygonal radial line parallel plate waveguide 102 is connected to multiple curved waveguides 103. The wide side length of each curved waveguide 103 is a, and the narrow side length is b. The length of the nth curved waveguide 103 is L1n. It consists of a first curved waveguide 131 at the same height as the polygonal radial line parallel plate waveguide 102 and a second curved waveguide 132 folded 180° toward the upper layer. The length of the first curved waveguide 131 is L1n1, and the length of the second curved waveguide 132 is L1n2.

[0038] Multiple curved waveguides 103 are fixedly connected to multiple rectangular waveguides 104, where the nth curved waveguide 103 is connected to the nth rectangular waveguide 104, and the length of the nth rectangular waveguide 104 is L2n. The multiple curved waveguides and the multiple rectangular waveguides form multiple branches, and the path length of each branch is equal. The output aperture of each rectangular waveguide is located at the same height and plane.

[0039] Furthermore, the CTS array 2 includes a parallel plate waveguide 201 and a CTS assembly 202. The parallel plate waveguide 201 includes an upper plate 211 and a lower plate 212 arranged parallel to the upper plate 211. An upper plate slow-wave structure 213 is provided on the end surface of the upper plate 211 facing the lower plate 212, and a lower plate slow-wave structure 214 is provided on the end surface of the lower plate 212 facing the upper plate 211. Both ends of the multiple upper plates 211 and lower plates 212 are fixedly connected by a sealing metal plate 3. A CTS assembly 202 is provided on the upper plate 211, and includes multiple first-order CTS branches 221 and multiple second-order CTS branches 222. The parallel plate waveguide 201 has a length d1 in the transmission direction and a length d2 in the other direction. Its height is H4. The upper plate 211 has a thickness t3, and the lower plate 212 has a thickness t3 at the beginning and increases to t4 at the end. The upper plate slow-wave structure 213 and the lower plate slow-wave structure 214 are both corrugated, and the overall trend of their undulation curves satisfies the sinusoidal function y=Asin(2πx / T), where A is the ripple amplitude of the slow-wave structure, and T is the ripple period of the slow-wave structure. The slow-wave structures 213 and 214 are placed at intervals of half a period T / 2 in the transmission direction.

[0040] The CTS component 202 is located on the upper plate 211 of the parallel plate waveguide and is composed of M first-order CTS branches 221 and M second-order CTS branches 222. The width of the mth first-order CTS branch 221m is W1m, and the width of the mth second-order CTS branch 222m is W2m, where 1≤m≤M. The height of the M second-order CTS branches 222 is H5, where H5 <t3。

[0041] Furthermore, the tops of the waveforms of the upper plate slow-wave structure 213 and the lower plate slow-wave structure 214 can be flattened to form flattened tops 231 , or additional ripples 232 can be added between the waveforms of the upper plate slow-wave structure 213 and the lower plate slow-wave structure 214 .

[0042] In this embodiment, the operating frequency is 9.5 GHz. For the mode conversion power distribution network, the coaxial waveguide inner conductor input end radius r1 = 15 mm, the output end radius r3 = 24.8 mm, the outer conductor input end radius r2 = 30 mm, the output end radius r4 = 39 mm, the coaxial waveguide transmission section height H1 = 33 mm, the inner conductor extension section radius r5 = 30 mm, and the height H2 = 12.6 mm. The radial parallel plate waveguide has 9 sides, a radius r6 = 46 mm, a metal partition thickness t1 = 1.6 mm, a metal slope radius r7 = 41 mm, and a height H3 = 8.6 mm. Taking the fifth bend waveguide and rectangular waveguide as examples, the waveguide width a = 28.5 mm, the narrow side b = 12.6 mm, the total length L15 of the bend waveguide = 232 mm, and the total length L25 of the rectangular waveguide = 90 mm.

[0043] The CTS array has a length of d1 = 251 mm, a width of d2 = 282 mm, and a height of H4 = 12.6 mm. The upper plate has a thickness of t3 = 5 mm, and the lower plate has a thickness of t4 = 11 mm at the output end. The slow-wave structure has a ripple amplitude of A = 2.3 mm and a period of T = 2π. The upper layer of the parallel plate waveguide features 10 radiating elements with a spacing of 25 mm. The height of each second-order CTS branch is H5 = 2 mm. The width dimensions of each branch are shown in Table 1.

[0044] Table 1 Size parameters corresponding to the branch width of each CTS unit

[0045]

[0046]

[0047] During operation, the electromagnetic wave is fed from the input end of the coaxial waveguide, reaches the radial line parallel plate waveguide, and then transmits radially outward to the input port of each curved waveguide. After being transmitted through the curved waveguide and rectangular waveguide with equal total electrical length, 9 TE with equal amplitude and phase are finally output on the same aperture surface. 10 Mode. 9 TE 10 The mode-synthesized plane wave is fed into the CTS array and transmitted as a traveling wave, radiating energy outward through the CTS branches. Because the cross-sectional area of ​​the slow-wave structure in the present invention changes slowly during the undulation process, it is less likely to cause an increase in the electric field and has high power characteristics.

[0048] Figure 7 The E-plane and H-plane radiation patterns of the present invention in this embodiment at 9.5 GHz are shown. It can be seen from the figure that the maximum gain of the antenna is in the normal direction, and the gain is 26 dBi.

[0049] Figure 8 The electric field distribution of the antenna cross-section of the present invention in this embodiment is shown when 650MW of energy is input at 9.5GHz. It can be seen that when the input energy is 650MW, the maximum electric field in the antenna is 79MV / m, which is lower than the vacuum breakdown threshold of 80MV / m at 9.5GHz. It can be seen that the present invention in this example has a power capacity of more than 650MW.

[0050] The number of devices and processing scales described herein are intended to simplify the description of the present invention, and the application, modification, and variation of the present invention will be apparent to those skilled in the art. Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiment. They can be applied to various fields suitable for the present invention. For those skilled in the art, additional modifications can be easily implemented. Therefore, the present invention is not limited to the specific details and illustrations shown and described herein without departing from the general concept defined by the claims and their equivalents.

Claims

1. A compact high-power CTS array antenna loaded with a slow-wave structure, characterized in that: include: A mode conversion power distribution network structure (1), a CTS array (2) cascaded with the mode conversion power distribution network structure (1), and sealing metal plates (3) on both sides of the CTS array; The CTS array (2) comprises a parallel plate waveguide (201) and a CTS component (202), wherein the parallel plate waveguide (201) comprises an upper plate (211) and a lower plate (212) arranged parallel to the upper plate (211), and an upper plate slow-wave structure (213) is arranged on the end surface of the upper plate (211) facing the lower plate (212), and a lower plate slow-wave structure (214) is arranged on the end surface of the lower plate (212) facing the upper plate (211); The upper plate slow-wave structure (213) and the lower plate slow-wave structure (214) are both corrugated, and the overall trend of their undulation curves satisfies the sine function y = Asin(2πx / T), where A is the ripple amplitude of the slow-wave structure, and T is the ripple period of the slow-wave structure. The slow-wave structures (213) and (214) are placed at intervals of half a period T / 2 in the transmission direction. The mode conversion power distribution network structure (1) comprises a special-shaped waveguide component, a coaxial waveguide component (101) arranged in the special-shaped waveguide component, and a polygonal radial line parallel plate waveguide (102) fixedly connected to the coaxial waveguide component, wherein the special-shaped waveguide component comprises a plurality of curved waveguides (103) and a plurality of rectangular waveguides (104) fixedly connected to the curved waveguides (103); a mounting step is formed by the plurality of curved waveguides (103) and the plurality of rectangular waveguides (104), and the mounting step is used to place a CTS array (2); The coaxial waveguide component (101) includes an outer conductor (112) and an inner conductor (111) disposed within the outer conductor (112), wherein the outer conductor (112) and the inner conductor (111) are spaced apart from each other, and an upper end portion of the inner conductor (111) extends from an upper end surface of the outer conductor (112); The polygonal radial line parallel plate waveguide (102) comprises a lower polygonal annular metal plate (122) fixed to the upper end face of the outer conductor (112), a metal inclined plate (124) fixed to the upper end face of the inner conductor (111), an upper polygonal metal plate (121) fixed to the upper end face of the metal inclined plate (124), and a plurality of metal spacers (123) uniformly fixed between the upper polygonal metal plate (121) and the lower polygonal annular metal plate (122), wherein the metal spacers (123) divide the interval between the upper polygonal metal plate (121) and the lower polygonal annular metal plate (122) into a plurality of identical output ports, and the output ports are connected to the interval between the outer conductor (112) and the inner conductor (111).

2. The compact high-power CTS array antenna loaded with a slow-wave structure according to claim 1, characterized in that: A CTS component (202) is provided on the upper plate (211), wherein the CTS component (202) comprises a plurality of first-order CTS branches (221) and a plurality of second-order CTS branches (222).

3. The compact high-power CTS array antenna loaded with a slow-wave structure according to claim 2, characterized in that: The plurality of curved waveguides (103) and the plurality of rectangular waveguides (104) form a plurality of branches, and the path length of each branch is equal. The output aperture of each rectangular waveguide (104) is at the same plane and the same height.

4. The compact high-power CTS array antenna loaded with a slow-wave structure according to claim 3, characterized in that: The tops of the waveforms of the upper plate slow-wave structure (213) and the lower plate slow-wave structure (214) can be flattened to form flattened tops (231), or additional ripples (232) can be added between the waveforms of the upper plate slow-wave structure (213) and the lower plate slow-wave structure (214).

5. The compact high-power CTS array antenna loaded with a slow-wave structure according to claim 4, characterized in that: The sealing metal plate (3) connects the mode conversion power distribution network structure (1) and the CTS array (2) at the same time.

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