Metal truss wave-transparent window and design method thereof

Abstract

This invention discloses a metal truss wave-transparent window and its design method, belonging to the field of radar antennas. Addressing the poor electromagnetic performance of existing metal truss wave-transparent windows, this invention provides a design method for a metal truss wave-transparent window. Using a regular pentagon as the initial core unit and its side length as a reference, a circumscribed or associated regular hexagonal grid is constructed. By introducing angular offsets to the interior angles of the regular hexagons, the inherent 120° rule is broken, introducing controllable, non-periodic "pseudo-random" variations in the grid's side length, node positions, and rod directions. This process is iteratively expanded, ultimately forming a large-area, pseudo-random triangular grid pattern without obvious repetition. This method mainly generates the pseudo-random triangular grid through a specific "regular pentagon-driven hexagonal angle array" geometric construction method. This grid completely breaks the inherent regular arrangement of traditional periodic metal grids or uniform grids, optimizing electrical performance while ensuring mechanical performance.

Description

Technical Field

[0001] This invention belongs to the field of radar antenna technology, and more specifically, relates to a metal truss wave-transparent window and its design method. Background Technology

[0002] Planar metal truss wave-transmitting windows are key components in large radomes (such as radomes and satellite communication radomes), integrating both structural support and electromagnetic wave transmission functions. Their core mission is to provide structural integrity for the entire system, ensuring the antenna's safety and stability during long-term operation and under various climatic conditions, while minimizing interference with the antenna signal, ensuring efficient electromagnetic wave penetration within the operating frequency band, and minimizing antenna gain loss. However, the members of traditional planar metal trusses are arranged uniformly or in parallel, and parallel members significantly degrade the antenna's electrical performance. The main impacts include: 1. Reflection and scattering cause a decrease in antenna gain and interfere with the radiation pattern; 2. Polarization sensitivity has the greatest impact on parallel polarization waves and will degrade polarization purity; 3. Resonance effect: When the length of the edge strip is close to half the wavelength, it will cause strong reflection, resulting in impedance mismatch and bandwidth limitation; 4. Periodic grid effect: If the grids are arranged at equal intervals and the spacing is too large, grid lobes will be generated, which will severely distort the beam.

[0003] To address the aforementioned issues, some corresponding technical improvements have been made. For example, Chinese patent application CN202111214142.4, published on January 4, 2022, discloses a method for improving the operational performance of an antenna system and a simulation method for antenna system operational performance. A metal truss electromagnetic window serves as the antenna system's protective cover, employing a variable cross-section electromagnetic window structure. This structure utilizes trusses of varying widths to create an irregularly pseudo-randomly distributed truss. This pseudo-randomly distributed truss counteracts the scattering effects between the trusses, thereby reducing the impact on the antenna system's electromagnetic performance and improving its operational performance. The variable cross-section electromagnetic window structure also optimizes the mechanical properties of the electromagnetic window. However, this patent has a drawback: the variable cross-section design, using a coarse-section truss on the outer hexagonal periphery and a fine-section truss inside, may significantly affect the antenna radiation pattern. Summary of the Invention

[0004] 1. The problem to be solved To address the poor electromagnetic performance of existing metal truss transmissive windows, this invention provides a metal truss transmissive window and its design method. The design method of this application generates a pseudo-random triangular mesh through a specific "regular pentagon-driven hexagonal angular array" geometric construction method. This mesh completely breaks the inherent regular arrangement of traditional periodic metal gratings or uniform meshes, dispersing the strong grating lobe scattering energy originally concentrated in a specific direction into incoherent weak scattering over a wide angular domain. This significantly reduces the radar cross-section of the transmissive window, effectively suppresses or even eliminates "grating lobes," significantly improves the antenna radiation pattern, reduces sidelobe levels, and increases antenna gain and signal purity. Simultaneously, simulations demonstrate that, while ensuring electromagnetic performance, the window possesses sufficient mechanical strength and stability to meet the practical requirements of complex environments (such as wind load and temperature variations).

[0005] 2. Technical Solution To solve the above problems, the present invention adopts the following technical solution.

[0006] A design method for a metal truss wave-transparent window includes the following steps: S1: Draw a basic shape, which is a regular pentagon; S2: Draw a circumscribed shape, wherein the circumscribed shape is a regular hexagon, and the regular hexagon includes a first side, a second side, a third side, a fourth side, a fifth side, and a sixth side connected in sequence; the first side and the fourth side are both sides extending in the horizontal direction; at the same time, the side length of the circumscribed shape is consistent with the side length of the base shape; S3: The circumscribed shape in step S2 is transformed as follows to obtain the deformed hexagon: Keep the lengths of the first, third, fourth, and fifth sides of the regular hexagon unchanged, and keep the relative positions of the first and fourth sides of the regular hexagon unchanged. Change the interior angle 'a' formed by the third and fourth sides and the interior angle 'b' formed by the fourth and fifth sides, so that 180° > a = b > 120°. S4: Assemble the deformed hexagon from step S3 onto the base shape to obtain the first assembled shape. The specific assembly is as follows: Connect one side of the deformed hexagon to one side of the base shape; then, using the centroid of the base shape as the center of rotation, perform a circular array five times, using the connection position relationship of the deformed hexagon relative to the base shape as the array unit, thereby generating an identical deformed hexagon on each of the remaining four sides of the base shape, and there is one side that overlaps between two adjacent deformed hexagons; wherein the side of the deformed hexagon is the first side, third side, fourth side, or fifth side of the deformed hexagon; S5: Reassemble the basic shape onto the first-assembled shape to obtain the second-assembled shape. The specific assembly is as follows: In one assembly of the figure, the base figure is reassembled on top of each deformed hexagon, such that one side of the base figure coincides with one side of the top of the deformed hexagon; wherein, all five base figures are assembled with the top of each deformed hexagon using the same side. S6: Draw the axis of symmetry: Connect the vertices between two adjacent basic figures to obtain a straight line, which forms the axis of symmetry; the two adjacent basic figures are the basic figures assembled by each deformed hexagon in the primary assembly figure and the secondary assembly figure. S7: Draw an octagon: Take two adjacent basic shapes, one as the starting point and the other as the ending point, and select one side from each of the two adjacent basic shapes and the two adjacent deformed hexagons along the direction of the axis of symmetry. The four sides are symmetrical along the axis of symmetry to obtain an octagon. S8: Assemble the octagon on the secondary assembly graphic according to steps S6~S7 to obtain the tertiary assembly graphic; S9: Reassemble the basic graphic in the installation area of ​​the three-stage assembly graphic to obtain the four-stage assembly graphic. The specific assembly is as follows: The basic shape is assembled in the installation area so that two sides of the basic shape coincide with two sides of the installation area; if the basic shape does not coincide with the installation area, the non-coincident sides of the basic shape are deleted, and the sides of the installation area are retained. At this time, the basic shape becomes a non-regular pentagon. The installation area of ​​the three-stage assembly graphic refers to the area between the octagon and the basic graphic. S10: Draw a hexagon: Connect the vertices of the non-regular pentagon and the octagon to obtain a straight line, which forms the axis of symmetry; take the non-regular pentagon and the octagon as the starting point and the octagon as the ending point, and select one side of each of the non-regular pentagon, the basic figure and the octagon along the direction of the axis of symmetry to obtain a hexagon; S11: Assemble the hexagons on the four-assembly graphic according to step S10 to obtain the five-assembly graphic; S12: In the five-fold assembly of the figure, find the centroid of the basic figure, the non-regular pentagon, the modified hexagon and the octagon, and connect the centroid of each figure to the vertices of the figure to obtain the basic figure, the non-regular pentagon, the modified hexagon and the octagon, which include several triangles. S13: Align the centroid of the transparent window with the centroid of the basic graphic in the five-fold assembly pattern of step S12, and delete the graphics outside the transparent window to obtain the final pseudo-randomly divided triangular mesh pattern; the basic graphic in the five-fold assembly pattern of step S12 is the basic graphic in the first-fold assembly pattern. S14: Simulate the final pseudo-randomly divided triangular mesh pattern to obtain a metal truss wave-transmitting window design that meets mechanical and electromagnetic performance requirements.

[0007] Furthermore, in step S3, the included angle α ranges from 126° to 130°.

[0008] Furthermore, before performing mechanical and electromagnetic performance simulations, step S14 determines the non-electrical performance working area and the electrical performance working area of ​​the wave-transmitting window in the final pseudo-randomly divided triangular mesh pattern, and the truss cross section used in the non-electrical performance working area of ​​the wave-transmitting window is larger than the truss cross section used in the electrical performance working area of ​​the wave-transmitting window.

[0009] Furthermore, the non-electrical performance working area of ​​the wave-transmitting window is selected to be 100mm. 50mm thick Q420 steel; the electrical performance working area of ​​the wave-transparent window is 100mm thick. 12mm thick 6061-T6 aluminum alloy.

[0010] A metal truss translucent window is designed using the design method of a metal truss translucent window as described in any of the above technical solutions.

[0011] 3. Beneficial effects This invention generates a pseudo-random triangular mesh through a specific geometric construction method of "regular pentagon driving hexagonal angular array". This mesh completely breaks the inherent regular arrangement of traditional periodic metal gratings or uniform meshes, and can effectively disrupt the coherent scattering conditions of electromagnetic waves, dispersing the strong grating lobe scattering energy originally concentrated in a specific direction into incoherent weak scattering in a wide-angle domain. As a result, the radar cross section of the transmission window is significantly reduced, "grating lobes" are effectively suppressed or even eliminated, the antenna radiation pattern is significantly improved, the sidelobe level is reduced, and the antenna gain and signal purity are improved. Meanwhile, the system allows for the addition of material to stress concentrations or critical load-bearing areas in the mesh, while reducing material in less important areas, based on the results of finite element analysis. This material distribution optimization based on mechanical state enables the final product to achieve higher structural strength, stiffness, and stability with the same or lighter weight, and to better withstand complex environmental loads such as wind loads, snow loads, vibration, and impact, thus significantly enhancing reliability. The entire design method uses a regular pentagon as the initial core unit, and its side length as the basis to construct an circumscribed or associated regular hexagonal grid. By introducing angular offsets to the interior angles of the regular hexagon, the inherent 120-degree angle rule is broken, thereby introducing controllable, non-periodic "pseudo-random" variations in the side length, node position, and rod direction of the grid. This process is iteratively expanded to eventually form a large-area pseudo-random triangular grid pattern without obvious repeating patterns. It successfully unifies the usually contradictory electromagnetic wave transmission requirements and structural stability requirements in the design of wave-transmitting windows. Moreover, it has strong designability, balanced performance, and is easy to implement in engineering. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of a regular pentagon; Figure 2 A schematic diagram of a regular hexagon transformed into a deformed hexagon; Figure 3 This is a structural diagram of a single-assembly graphic; Figure 4 This is a structural diagram of a secondary assembly graphic; Figure 5 This is a schematic diagram of the axis of symmetry in the secondary assembly diagram; Figure 6 This is a schematic diagram of the forming process of an octagon in a secondary assembly graphic; Figure 7 This is a structural diagram of a three-stage assembly graphic; Figure 8 This is a schematic diagram of the installation area in the three-stage assembly diagram; Figure 9 This is a structural diagram of a four-stage assembly graphic; Figure 10 This is a schematic diagram illustrating the forming process of the hexagon in the four-stage assembly pattern. Figure 11 This is a structural diagram of a five-stage assembly graphic; Figure 12 The diagram shows the basic shape containing a triangle, as well as the structural diagrams of non-regular pentagons, modified hexagons, and octagons. Figure 13 This is a schematic diagram of a five-stage assembly graphic containing triangles. Figure 14 A schematic diagram illustrating the formation process of the final pseudo-randomly divided triangular mesh pattern; Figure 15 This is a simulation diagram. Detailed Implementation

[0013] The present invention will now be further described with reference to specific embodiments and accompanying drawings.

[0014] A design method for a metal truss wave-transparent window includes the following steps: S1: Draw a basic shape, which is a regular pentagon, such as... Figure 1 As shown; S2: Draw a circumscribed shape, wherein the circumscribed shape is a regular hexagon, and the regular hexagon includes a first side, a second side, a third side, a fourth side, a fifth side, and a sixth side connected in sequence; the first side and the fourth side are both sides extending in the horizontal direction; at the same time, the side length of the circumscribed shape is consistent with the side length of the base shape; S3: The circumscribed shape in step S2 is transformed as follows to obtain the deformed hexagon: Keeping the lengths of the first, third, fourth, and fifth sides of the regular hexagon unchanged, and keeping the relative positions of the first and fourth sides unchanged, change the interior angle 'a' formed by the third and fourth sides and the interior angle 'b' formed by the fourth and fifth sides, such that 180° > a = b > 120°; Figure 2 As shown, Figure 2 The left part is a regular hexagon, and the right part is a deformed hexagon; that is to say, this step breaks the inherent 120-degree angle rule of the interior angle of the regular hexagon, thereby laying the foundation for the subsequent introduction of controllable, non-periodic "pseudo-random" changes in the side length, node position and rod direction of the grid. Generally, for feasibility, the included angle α is typically chosen to be between 126° and 130°. If the included angle α is too large, it will cause the hexagonal shape to become extremely flat or distorted. Although this strong local deformation can break the periodicity, it will make the connection angle between adjacent units too sharp or the difference in the length of the rods too large, worsening the stress distribution of the structure, creating local weak points, and possibly forming new, irregular electromagnetic scattering concentration areas in certain directions. Within this angle range, there is high operability and feasibility, and no other problems will interfere. S4: Assemble the deformed hexagon from step S3 onto the base shape to obtain the first assembled shape, as shown in the example below. Figure 3 As shown, the specific assembly is as follows: Connect one side of the deformed hexagon to one side of the base shape; then, using the centroid of the base shape as the center of rotation, perform a circular array five times, using the connection positions of the deformed hexagon relative to the base shape as array units, thereby generating an identical deformed hexagon on each of the remaining four sides of the base shape, with one side overlapping between adjacent deformed hexagons; wherein the side of the deformed hexagon is the first, third, fourth, or fifth side of the deformed hexagon; that is, assemble the deformed hexagon in step S3 into the regular pentagon in step S1, and array it five times along the centroid of the regular pentagon to obtain the shape as shown. Figure 3 The diagram shown is a single assembly diagram; S5: Reassemble the basic shape onto the first-assembled shape to obtain the second-assembled shape, as shown in the example. Figure 4 As shown, the specific assembly is as follows: In one assembly of the figure, the base figure is reassembled on top of each deformed hexagon, such that one side of the base figure coincides with one side of the top of the deformed hexagon; wherein, all five base figures are assembled with the top of each deformed hexagon using the same side. This indicates that the edge corresponding to the top of the deformed hexagon is the edge of the deformed hexagon that is furthest from the regular pentagon. The edge where the deformed hexagon and the regular hexagon coincide is called the coincident edge. The edge corresponding to the top of the deformed hexagon is positioned opposite the coincident edge. After the regular hexagon in step S1 is assembled to the top of the deformed hexagon, the regular pentagon in step S1 is then arrayed five times along its centroid five times to obtain the following... Figure 4 The secondary assembly diagram shown; S6: Draw the axis of symmetry: Connect the vertices between two adjacent basic figures to obtain a straight line AB, as shown in Figure 1. Figure 5 As shown, the straight line forms an axis of symmetry; two adjacent basic shapes are the basic shapes assembled with each deformed hexagon in the primary assembly shape in the secondary assembly shape; S7: Draw an octagon: Take two adjacent basic shapes, one as the starting point and the other as the ending point, and select one side from each of the two adjacent basic shapes and the two adjacent deformed hexagons along the direction of the axis of symmetry. The four sides are symmetrical along the axis of symmetry to obtain an octagon. like Figure 6 As shown, specifically, Figure 6 The left part is a schematic diagram showing the selection of the four sides of the octagon; Figure 6 The right side is a schematic diagram of the octagonal structure; that is, along the direction of the axis of symmetry, one side of each of two adjacent basic figures is selected sequentially. Figure 6 The numbers 1 and 4, and one side of the two adjacent deformed hexagons between two adjacent basic figures, are... Figure 6 2 and 3 in the middle; S8: Assemble the octagons on the secondary assembly graphic according to steps S6-S7 to obtain the tertiary assembly graphic; that is, after determining an octagon assembly method, arrange the regular pentagons along the centroid of the primary assembly graphic five times to obtain the tertiary assembly graphic. Figure 7 The diagram shows a three-stage assembly. S9: Reassemble the basic graphic in the installation area of ​​the three-stage assembly graphic to obtain the four-stage assembly graphic. The four-stage assembly graphic is as follows: Figure 9 As shown; the specific assembly is as follows: The basic shape is assembled in the installation area so that two sides of the basic shape coincide with two sides of the installation area; if the basic shape does not coincide with the installation area, the non-coincident sides of the basic shape are deleted, and the sides of the installation area are retained. At this time, the basic shape becomes a non-regular pentagon. In this context, the installation area of ​​the three-stage assembly refers to the space between the octagon and the base graphic. The base graphic in the installation area refers to the base graphic connected to the octagon. One side of each of the octagon and the base graphic coincides with two sides of the base graphic to be assembled. Since the side lengths of the base graphic and the base graphic to be assembled are equal, complete overlap is achieved. However, if one side of the octagon is not equal to the side length of the base graphic to be assembled, such as... Figure 8 As shown by the red circle, when the sides are unequal, the side lengths of the basic shapes to be assembled are removed, and the side length of the octagon is used as the reference. At this point, the basic shapes to be assembled become non-regular pentagons. That is, after determining the assembly method for a non-regular pentagon, arranging the regular pentagons along their centroids five times in one assembly step yields the shape shown in the red circle. Figure 9 The four-stage assembly diagram shown; S10: Draw a hexagon: Connect the vertices of the non-regular pentagon and the octagon to obtain a straight line, which forms the axis of symmetry; take the non-regular pentagon and the octagon as the starting point and the octagon as the ending point, and select one side of each of the non-regular pentagon, the basic figure and the octagon along the direction of the axis of symmetry to obtain a hexagon; Specifically, such as Figure 10 As shown, Figure 10 The left part of the diagram shows the hexagonal axis of symmetry and the selection of the three sides; Figure 10 The right part is a schematic diagram of the structure of a hexagon; that is, connecting the vertices between the non-regular pentagon and the octagon gives the axis of symmetry CD. Along the axis of symmetry CD, select one side 5 of the non-regular pentagon, one side 6 of the regular pentagon, and one side 7 of the octagon, and symmetrically along CD to obtain the hexagon. S11: Assemble the hexagons on the four-fold assembled shape according to step S10 to obtain the five-fold assembled shape, as shown in the figure below. Figure 11 As shown, after determining the assembly method of a hexagon, arranging the regular pentagons along the centroid of the first assembly figure five times yields the result shown below. Figure 11 The five-stage assembly diagram shown; S12: In the five-fold assembly of the figures, find the centroids of the basic figure, the non-regular pentagon, the modified hexagon, and the octagon, and connect each centroid to a vertex in its respective figure to obtain the basic figure, the non-regular pentagon, the modified hexagon, and the octagon, which include several triangles. Figure 12 As shown; after obtaining the triangular divisions of each basic shape, non-regular pentagon, modified hexagon, and octagon, the overall division of the five-fold assembled shape yields the overall division diagram, as shown. Figure 13 As shown; S13: Align the centroid of the transparent window with the centroid of the basic graphic in the five-fold assembly pattern of step S12, and delete the graphics outside the transparent window to obtain the final pseudo-randomly divided triangular mesh pattern; the basic graphic in the five-fold assembly pattern of step S12 is the basic graphic in the first-fold assembly pattern. Generally, the transparent window is rectangular. The centroid of the rectangle is aligned with the centroid of the basic graphic in the five-stage assembly in step S12, as shown on the left side of Figure 14. Simultaneously, excess external line segments are trimmed, and the edge nodes of the rectangle are fine-tuned (to make the triangle areas similar). That is, after the centroid of the rectangle coincides with the centroid of the basic graphic, the line segments outside the rectangle are discarded, and only the pseudo-random triangles within the rectangle are retained. These triangles may be truncated by the rectangle in the middle, and the resulting nodes need to be translated to the edge of the rectangle. This yields the final pseudo-randomly divided triangles, as shown in the figure. Figure 14 As shown in the right part of the image; S14: Simulate the final pseudo-randomly divided triangular mesh pattern to obtain a metal truss wave-transmitting window design that meets mechanical and electromagnetic performance requirements. Specifically, regarding the simulation steps, after obtaining the final pseudo-randomly divided triangular mesh pattern, it is necessary to convert the final pseudo-randomly divided triangular mesh pattern into a solid metal truss for simulation to ensure that it meets the mechanical and electromagnetic properties. The dimensions of the solid metal truss can be modified according to the simulation results. Specifically, before performing mechanical and electromagnetic performance simulations, step S14 determines the non-electrical performance working area and the electrical performance working area of ​​the wave-transmitting window in the final pseudo-randomly divided triangular mesh pattern, and the truss cross section used in the non-electrical performance working area of ​​the wave-transmitting window is larger than the truss cross section used in the electrical performance working area of ​​the wave-transmitting window. In other words, the members in the truss of this application are not of uniform cross-section, but adopt a variable cross-section design. That is, the cross-sectional dimensions of the members (such as width and thickness) can be adaptively adjusted and optimized according to their position in the overall grid, stress state, or local electromagnetic field distribution. For example, the width is determined according to the operating frequency of the radome, which is generally one wavelength of the maximum operating frequency of the antenna, and the thickness is determined according to the mechanical simulation index to meet the requirements. Variable cross-section design allows for the addition of material in stress concentration or critical load-bearing areas, while reducing material in less critical areas. This enables the optimization of structural strength and efficient use of materials without increasing or even reducing the overall weight. This allows the translucent window to better resist environmental loads such as wind, snow, and vibration, meeting the requirements for long-term reliable use.

[0015] Specifically, such as Figure 15 As shown, this embodiment uses the following material as an example: the non-electrical performance working area of ​​the wave-transmitting window, i.e. Figure 15 The blue area in the image is 100mm. 50mm thick Q420 steel; the electrical performance working area of ​​the wave-transparent window is 100mm thick. Simulation using 12mm 6061-T6 aluminum alloy: Mechanical simulation was carried out using finite element software. Under the action of 1 times the wind load of 45 m / s + 1.3 times the self-weight load, the maximum stress of the rod is 416 MPa < the yield strength of 420 MPa of the steel rod, and the maximum deformation of the rod is 229.6 mm; the maximum stress of the membrane surface is 3.5 MPa < the tensile strength of 170 MPa of the PTFE membrane material; the overall maximum deformation is 229.6 mm; Electromagnetic simulation was carried out using finite element software. Input conditions: a 7.3-meter dual-reflector antenna, and the antenna is 1.8 meters away from the wave-transmitting window. Simulation results: the transmission loss in C / X / Ku bands ≤ 0.90 dB; the transmission loss in L / S / Ka bands ≤ 0.99 dB; the cross polarization ≥ 27.36 dB; the beam broadening ≤ 0.71%; the deterioration of the first sidelobe level ≤ 0.31 dB.

[0016] It can be seen that the design method of this application can effectively suppress and even eliminate "grating lobes", significantly improve the antenna radiation pattern, reduce the sidelobe level, and improve the gain and signal purity of the antenna; at the same time, without increasing or even reducing the total weight, the optimization of structural strength and the efficient utilization of materials are realized; this enables the wave-transmitting window to better resist environmental loads such as wind, snow, and vibration, and meet the requirements of long-term reliable use.

[0017] A metal truss wave-transmitting window is designed by using the design method of a metal truss wave-transmitting window described in any one of the above technical solutions. This metal truss wave-transmitting window unifies the usually conflicting electromagnetic wave-transmitting requirements and structural stability requirements in the design of the wave-transmitting window, has strong designability, balanced performance, and is easy to be realized in engineering.

[0018] The examples described in the present invention are only descriptions of the preferred embodiments of the present invention, and do not limit the concept and scope of the present invention. Without departing from the design idea of the present invention, various deformations and improvements made by those skilled in the art to the technical solutions of the present invention shall fall within the protection scope of the present invention.

Claims

1. A method of designing a metal truss wave-transparent window, characterized by: Includes the following steps: S1: Draw a basic shape, which is a regular pentagon; S2: Draw a circumscribed shape, wherein the circumscribed shape is a regular hexagon, and the regular hexagon includes a first side, a second side, a third side, a fourth side, a fifth side, and a sixth side connected in sequence; the first side and the fourth side are both sides extending in the horizontal direction; at the same time, the side length of the circumscribed shape is consistent with the side length of the base shape; S3: The circumscribed shape in step S2 is transformed as follows to obtain the deformed hexagon: Keep the lengths of the first, third, fourth, and fifth sides of the regular hexagon unchanged, and keep the relative positions of the first and fourth sides of the regular hexagon unchanged. Change the interior angle 'a' formed by the third and fourth sides and the interior angle 'b' formed by the fourth and fifth sides, so that 180° > a = b > 120°. S4: Assemble the deformed hexagon from step S3 onto the base shape to obtain the first assembled shape. The specific assembly is as follows: Connect one side of the deformed hexagon to one side of the base shape; then, using the centroid of the base shape as the center of rotation, perform a circular array five times, using the connection position relationship of the deformed hexagon relative to the base shape as the array unit, thereby generating an identical deformed hexagon on each of the remaining four sides of the base shape, and there is one side that overlaps between two adjacent deformed hexagons; wherein the side of the deformed hexagon is the first side, third side, fourth side, or fifth side of the deformed hexagon; S5: Reassemble the basic shape onto the first-assembled shape to obtain the second-assembled shape. The specific assembly is as follows: In one assembly of the figure, the base figure is reassembled on top of each deformed hexagon, such that one side of the base figure coincides with one side of the top of the deformed hexagon; wherein, all five base figures are assembled with the top of each deformed hexagon using the same side. S6: Draw the axis of symmetry: Connect the vertices between two adjacent basic figures to obtain a straight line, which forms the axis of symmetry; the two adjacent basic figures are the basic figures assembled by each deformed hexagon in the primary assembly figure and the secondary assembly figure. S7: Draw an octagon: Take two adjacent basic shapes, one as the starting point and the other as the ending point, and select one side from each of the two adjacent basic shapes and the two adjacent deformed hexagons along the direction of the axis of symmetry. The four sides are symmetrical along the axis of symmetry to obtain an octagon. S8: Assemble the octagon on the secondary assembly graphic according to steps S6~S7 to obtain the tertiary assembly graphic; S9: Reassemble the basic graphic in the installation area of ​​the three-stage assembly graphic to obtain the four-stage assembly graphic. The specific assembly is as follows: The basic shape is assembled in the installation area so that two sides of the basic shape coincide with two sides of the installation area; if the basic shape does not coincide with the installation area, the non-coincident sides of the basic shape are deleted, and the sides of the installation area are retained. At this time, the basic shape becomes a non-regular pentagon. The installation area of ​​the three-stage assembly graphic refers to the area between the octagon and the basic graphic. S10: Draw a hexagon: Connect the vertices of the non-regular pentagon and the octagon to obtain a straight line, which forms the axis of symmetry; take the non-regular pentagon and the octagon as the starting point and the octagon as the ending point, and select one side of each of the non-regular pentagon, the basic figure and the octagon along the direction of the axis of symmetry to obtain a hexagon; S11: Assemble the hexagons on the four-assembly graphic according to step S10 to obtain the five-assembly graphic; S12: In the five-fold assembly of the figure, find the centroid of the basic figure, the non-regular pentagon, the modified hexagon and the octagon, and connect the centroid of each figure to the vertices of the figure to obtain the basic figure, the non-regular pentagon, the modified hexagon and the octagon, which include several triangles. S13: Align the centroid of the transparent window with the centroid of the basic graphic in the five-fold assembly pattern of step S12, and delete the graphics outside the transparent window to obtain the final pseudo-randomly divided triangular mesh pattern; the basic graphic in the five-fold assembly pattern of step S12 is the basic graphic in the first-fold assembly pattern. S14: Simulate the final pseudo-randomly divided triangular mesh pattern to obtain a metal truss wave-transmitting window design that meets mechanical and electromagnetic performance requirements.

2. The method of designing a metal truss wave-transparent window according to claim 1, wherein: In step S3, the included angle α ranges from 126° to 130°.

3. The method of designing a metal truss wave-transparent window according to claim 1, wherein: Before performing mechanical and electromagnetic performance simulations, step S14 determines the non-electrical performance working area and the electrical performance working area of ​​the wave-transmitting window in the final pseudo-randomly divided triangular mesh pattern, and the truss cross section used in the non-electrical performance working area of ​​the wave-transmitting window is larger than the truss cross section used in the electrical performance working area of ​​the wave-transmitting window.

4. The method of designing a metal truss wave-transparent window according to claim 3, wherein: 100 mm of Q420 steel material for the non-electrically active region of the wave-transparent window 50 mm of Q420 steel material for the electrically active region of the wave-transparent window 12 mm of 6061-T6 aluminum alloy.

5. A metal truss wave-transparent window, characterized by: It is designed using the design method of a metal truss wave-transparent window as described in any one of claims 1-4.

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