Honeycomb structure, interference preventing device, and application

Abstract

This invention discloses a honeycomb structure, an anti-interference device, and its application. The honeycomb structure may include multiple electromagnetic wave absorbing units arranged sequentially on the same plane. Each electromagnetic wave absorbing unit may include a hexagonal honeycomb substrate, multiple resistive elements layered on the inner wall of the hexagonal honeycomb substrate, and multiple copper sheets disposed on the inner wall of the hexagonal honeycomb substrate. Adjacent resistive elements in the same layer are connected sequentially through the copper sheets to form a ring-shaped resistive network. The electromagnetic wave absorbing unit includes a first end and a second end, and the resistance value of the resistive elements in the multi-layer ring-shaped resistive network increases layer by layer from the first end to the second end. This honeycomb structure, while maintaining lightweight and high strength, effectively forms an impedance gradient and ohmic loss mechanism, thereby solving the problems of narrow electromagnetic wave absorption bandwidth, complex manufacturing process, and heavy weight of traditional electromagnetic wave absorbing honeycomb structures, achieving efficient and stable electromagnetic wave absorption in a wide frequency range of 1.72-18 GHz.

Description

Technical Field

[0001] This invention relates to the field of electromagnetic wave absorbing materials technology, and in particular to a honeycomb structure, anti-interference device and its application. Background Technology

[0002] Electromagnetic wave absorbing honeycomb structures, as a functional composite material that combines high mechanical strength, lightweight properties, and excellent electromagnetic wave absorption performance, have broad application prospects in areas such as aircraft stealth, electromagnetic compatibility, and microwave anechoic chambers.

[0003] Traditional electromagnetic wave absorbing honeycomb structures primarily achieve their absorption performance by impregnating the honeycomb matrix (such as a honeycomb core made of aramid paper or glass fiber reinforced composites) with an electromagnetic wave absorbing coating. This process utilizes the lossy substances in the coating (such as carbonaceous materials or magnetic materials) to convert the energy of the incident electromagnetic waves into heat energy, thus achieving absorption. However, this method has two significant limitations: First, to achieve sufficient electromagnetic wave absorption, a large amount of coating is often required, which significantly increases the overall weight of the structure, contradicting the initial goal of lightweight honeycomb structures; second, single-component and structural electromagnetic wave absorbing coatings are usually only effective within a specific frequency band, resulting in a narrow electromagnetic wave absorption bandwidth, which is insufficient to meet the urgent needs of modern electronic systems for broadband electromagnetic wave absorption performance.

[0004] To overcome the inherent defects of traditional impregnated coating honeycomb, existing technologies have proposed a variety of improvement schemes, but these improvements still struggle to achieve an ideal balance between performance, process, and cost. Summary of the Invention

[0005] This invention was developed to address the technical problems of narrow electromagnetic wave absorption bandwidth, poor process stability, and complex structure inherent in traditional electromagnetic wave absorbing honeycomb structures.

[0006] As one aspect of the present invention, an embodiment of the present invention provides a honeycomb structure, which may include: a plurality of electromagnetic wave absorbing units arranged sequentially on the same plane; each electromagnetic wave absorbing unit may include: a hexagonal honeycomb substrate, a plurality of resistive elements layered on the inner wall of the hexagonal honeycomb substrate, and a plurality of copper sheets disposed on the inner wall of the hexagonal honeycomb substrate.

[0007] The adjacent resistive elements on the same layer are connected in sequence through the copper sheet to form a ring-shaped resistive network;

[0008] The electromagnetic wave absorption unit includes a first end and a second end, and the resistance value of the resistive element in the multilayer ring resistor network increases layer by layer from the first end to the second end.

[0009] In one embodiment, the ring resistor network has four layers, and each layer of the ring resistor network is parallel to the plane in which the plurality of electromagnetic wave absorbing units are located;

[0010] The vertical distance between the first layer of the ring resistor network and the first end is 4~6mm;

[0011] The vertical distance between the second layer of the ring resistor network and the first end is 10~12mm;

[0012] The vertical distance between the third layer of the ring resistor network and the first end is 14~16mm;

[0013] The vertical distance between the fourth layer of the ring resistor network and the first end is 22~24mm.

[0014] In one embodiment, the resistance of the resistive element in the first layer of the ring resistor network is R, where R is 150~300Ω;

[0015] The resistance of the resistor element in the second-layer ring resistor network is 2R;

[0016] The resistance of the resistor element in the third-layer ring resistor network is 4R;

[0017] The resistance of the resistor element in the fourth-layer ring resistor network is 8R.

[0018] In one embodiment, the hexagonal honeycomb substrate is made of aramid paper; the relative permittivity of the hexagonal honeycomb substrate is 2.5, and the loss angle is 0.005.

[0019] In one embodiment, each side of the hexagonal honeycomb substrate is 3 mm long, the wall thickness is 0.13 mm, and the height is 30 mm.

[0020] In one embodiment, the copper sheet is rectangular and is disposed on the inner wall of the connection between adjacent sides of the hexagonal honeycomb substrate. Each copper sheet is 1 mm long and 0.5 mm wide.

[0021] In one embodiment, the copper sheet is mounted on the inner wall of the hexagonal honeycomb substrate using circuit printing technology or adhesive bonding.

[0022] In one embodiment, the resistive element is soldered between the copper sheets using tin.

[0023] As another aspect of the present invention, an embodiment of the present invention provides an anti-interference device, wherein the outer surface of the anti-interference device is attached with the above-mentioned honeycomb structure.

[0024] As another aspect of the present invention, an embodiment of the present invention provides an application of the above-described honeycomb structure in an anti-interference device.

[0025] The beneficial effects of the above-mentioned technical solutions provided in the embodiments of the present invention include at least the following:

[0026] This invention provides a honeycomb structure, an anti-interference device, and an application. The honeycomb structure uses resistive elements with increasing resistance from bottom to top arranged in layers on the inner wall of its hexagonal aramid paper honeycomb matrix, and connects them in the same layer using copper sheets. While maintaining the structure's lightweight and high strength, it effectively forms an impedance gradient and ohmic loss mechanism, thereby solving the problems of narrow electromagnetic wave absorption bandwidth, complex manufacturing process, and heavy weight of traditional electromagnetic wave absorption honeycomb structures, and achieving efficient and stable electromagnetic wave absorption in a wide frequency range of 1.72-18GHz.

[0027] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings.

[0028] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0029] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0030] Figure 1 This is a structural diagram of the honeycomb structure provided in the embodiments of the present invention;

[0031] Figure 2 The reflection loss curve of the honeycomb structure provided in Embodiment 1 of the present invention;

[0032] Figure 3 A structural diagram of the electromagnetic wave absorption unit provided for Comparative Example 1;

[0033] Figure 4 The reflection loss curve of the cellular structure provided for Comparative Example 1;

[0034] Wherein, 1-honeycomb structure; 2-metal reflector;

[0035] 11-Electromagnetic wave absorption unit;

[0036] 111-Hexagonal honeycomb substrate; 112-Resistor element; 113-Copper sheet; 114-First layer ring resistor network; 115-Second layer ring resistor network; 116-Third layer ring resistor network; 117-Fourth layer ring resistor network; 1111-First end; 1112-Second end. Detailed Implementation

[0037] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0038] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," "outer," "far," "near," "front," and "rear," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0039] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0040] For example, in patent application CN119795706A, entitled "A Gradient Structure Honeycomb Absorbing Plate and Its Preparation Method and Application," the honeycomb unit structure is designed with a tapered gradient shape. Impedance matching is achieved through structural gradient without significantly increasing the areal density, thereby broadening the electromagnetic wave absorption bandwidth. The absorber disclosed in this patent achieves excellent electromagnetic wave absorption performance with a reflection loss of less than -10dB in the frequency range of 4.4GHz to 16.2GHz. However, the inventors discovered in their research that the preparation process of this three-dimensional tapered gradient honeycomb structure is complex, requiring extremely high precision in mold design and manufacturing, resulting in high production costs and limiting its large-scale application.

[0041] For example, patent application CN109774211A, entitled "Preparation Method of Impedance Gradient Absorbing Honeycomb," aims to improve electromagnetic wave absorption performance by impregnating different concentrations of absorbing coatings in different layers to form a layered structure with gradually varying impedance. While this method theoretically optimizes impedance matching, in actual production, the layered impregnation steps for different concentrations of coatings are cumbersome, and process parameters (such as impregnation time, lifting speed, and concentration gradient control) are difficult to control precisely. This results in poor product performance consistency, insufficient process stability, and challenges in achieving high yield rates.

[0042] For example, patent application CN119767658A, entitled "A Broadband Sidewall Patterned Absorbing Honeycomb Structure," takes a different approach, choosing not to impregnate the honeycomb with coating, but instead loading patterned resistive films onto the honeycomb sidewalls using a specific process. This patent can achieve good electromagnetic wave absorption in an extremely wide frequency band of 2-18GHz. However, its technical bottleneck lies in the fact that the thickness of the resistive film layer is extremely difficult to control precisely during the deposition or coating process, directly leading to large fluctuations in its key performance parameter—sheet resistance—affecting the uniformity and reliability of product performance. At the same time, the patterning process has stringent requirements for pattern precision, and the involved processes (such as photolithography and precision printing) are also complex and costly.

[0043] The inventors, through summarizing existing improvement methods, found that existing improvements to electromagnetic wave absorbing honeycomb structures either focus on enhancing performance through complex structural designs at the expense of cost and manufacturability, or rely on delicate processes that are difficult to control stably. Therefore, there is an urgent need in the field for a new technical solution that can guarantee wide-bandwidth, high-efficiency electromagnetic wave absorption performance while also possessing advantages such as simple processes, controllable manufacturing costs, and stable product performance, to better meet the needs of practical applications.

[0044] To address the technical problems of narrow electromagnetic wave absorption bandwidth, poor process stability, and complex structure in current electromagnetic wave absorbing honeycomb structures, the inventors aimed to develop a honeycomb structure with load resistive elements. Through persistent efforts, this invention was developed. After numerous experiments, it was discovered that layering multiple resistive elements with different resistance values ​​in different layers creates a gradient impedance between layers. This reduces the impedance difference between different media along the electromagnetic wave propagation path, allowing more electromagnetic waves to enter the structure and be attenuated, achieving unexpected technical benefits.

[0045] This invention provides a honeycomb structure, as shown in the following embodiment. Figure 1As shown, the honeycomb structure 1 may include: a plurality of electromagnetic wave absorbing units 11 arranged sequentially on the same plane; each electromagnetic wave absorbing unit 11 may include: a hexagonal honeycomb substrate 111, a plurality of resistive elements 112 layered on the inner wall of the hexagonal honeycomb substrate 111, and a plurality of metal copper sheets 113 disposed on the inner wall of the hexagonal honeycomb substrate 111; adjacent resistive elements 112 in the same layer are sequentially connected to form a ring resistive network through the metal copper sheets 113; the electromagnetic wave absorbing unit 11 includes a first end 1111 and a second end 1112, and the resistance value of the resistive elements 112 in the multi-layer ring resistive network increases layer by layer from the direction closer to the first end 1111 to the direction closer to the second end 1112.

[0046] In this embodiment, a metal reflector 2 is placed at the bottom near the first end 1111 during testing, and the electromagnetic wave incident direction is a radial direction perpendicular to the metal reflector 2. It should be noted that the resistive element in this embodiment is a surface mount resistor, which is a commercially available product, and its resistance value, shape, and size can be selected as needed.

[0047] The honeycomb structure provided in this embodiment of the invention arranges multiple electromagnetic wave absorbing units 11 closely in the same plane, and sets resistive elements 112 connected by metal copper sheets 113 in layers on the inner wall of each hexagonal honeycomb substrate 111 to form a multi-layer ring resistive network. This makes the resistance value increase layer by layer from low to high along the incident direction of electromagnetic waves, thereby achieving excellent impedance matching and electromagnetic wave absorption performance in a wide frequency range of 1.72-18GHz. At the same time, the structure has high strength, controllable process, and is easy to integrate, overcoming the problems of narrow bandwidth and complex process of traditional electromagnetic wave absorbing materials.

[0048] In this embodiment of the invention, the hexagonal honeycomb substrate 111 is made of aramid paper; the relative permittivity of the hexagonal honeycomb substrate 111 is 2.5, and the loss angle is 0.005. By specifying that the hexagonal honeycomb substrate 111 is made of aramid paper and specifying its relative permittivity of 2.5 and loss angle of 0.005, the honeycomb structure achieves low reflection and high-efficiency absorption of electromagnetic waves while possessing good mechanical strength and lightweight characteristics. This enhances the impedance matching and electromagnetic wave loss capability of the overall structure in a wide frequency band (1.72-18GHz), thereby improving the stability and process feasibility of electromagnetic wave absorption performance.

[0049] In this embodiment, each side of the hexagonal honeycomb substrate 111 has a length of 3 mm, a wall thickness of 0.13 mm, and a height of 30 mm. While ensuring a lightweight and high-strength structure, the hexagonal honeycomb substrate 111, in conjunction with the gradient resistor network, optimizes the propagation path and impedance matching of electromagnetic waves within the honeycomb structure, thereby achieving stable and efficient electromagnetic wave absorption performance over a wide frequency range of 1.72-18 GHz.

[0050] It should be noted that the copper sheet 113 in this embodiment is rectangular and is disposed on the inner wall of the connection between adjacent sides of the hexagonal honeycomb substrate 111. Each copper sheet 113 is 1 mm long and 0.5 mm wide. By limiting the copper sheet 113 to be rectangular with a length of 1 mm and a width of 0.5 mm, and disposing it on the inner wall of the connection between adjacent sides of the hexagonal honeycomb substrate 111, a precise layout and spatial optimization of the connection structure between the resistor elements 112 are achieved. This ensures the formation of a stable, low-loss annular conductive path between the resistor elements 112 in the same layer, while avoiding the encroachment on the overall lightweight nature of the honeycomb structure and the electromagnetic wave incident space. Thus, while maintaining the mechanical strength of the structure, the integration degree of the gradient resistor network and the consistency of the high-frequency electromagnetic response are effectively improved.

[0051] It should be further explained that the copper sheet 113 is mounted on the inner wall of the hexagonal honeycomb substrate 111 using circuit printing technology or adhesive bonding. By using circuit printing technology or adhesive bonding to mount the copper sheet 113 on the inner wall of the hexagonal honeycomb substrate 111, not only is the manufacturing process simplified and the consistency and reliability of the structure improved, but also a stable connection between the resistive element 112 and the copper sheet 113 is ensured. This guarantees the accurate realization of the gradient resistor network and the efficient and stable electromagnetic wave absorption performance of the overall honeycomb structure in a wide frequency band (1.72-18GHz).

[0052] In this embodiment of the invention, the resistive element 112 is soldered between the copper sheets 113 with tin, which ensures a stable and low-impedance electrical connection between the resistive element 112 and the copper sheets 113, improving the electrical continuity and mechanical robustness of the structure. This enhances the electromagnetic wave absorption performance and reliability of the overall honeycomb structure in a wide frequency band (1.72-18GHz), while simplifying the manufacturing process and facilitating mass production and quality control.

[0053] This invention provides a honeycomb structure, an anti-interference device, and its application. The honeycomb structure uses resistive elements 112 with increasing resistance from bottom to top arranged in layers on the inner wall of its hexagonal aramid paper honeycomb matrix, and connects them in the same layer using copper sheets 113. While maintaining the structure's lightweight and high strength, it effectively forms an impedance gradient and ohmic loss mechanism, thereby solving the problems of narrow electromagnetic wave absorption bandwidth, complex manufacturing process, and heavy weight of traditional honeycomb structures, and achieving efficient and stable electromagnetic wave absorption in a wide frequency range of 1.72-18GHz.

[0054] The following are three embodiments and a comparative example provided by this invention, along with test results:

[0055] Example 1

[0056] In Example 1, the honeycomb structure 1 is composed of several hexagonal electromagnetic wave absorbing units 11 arranged closely together, as shown in the figure. Figure 1 As shown, the hexagonal electromagnetic wave absorbing unit 11 includes a hexagonal honeycomb substrate 111, a resistive element 112 loaded on the inner wall of the hexagonal electromagnetic wave absorbing unit 11, and a metal copper sheet 113 connected to the resistive element 112. During testing, a metal reflector 2 is set at the bottom near the first end 1111, and the electromagnetic wave incident direction is the radial direction perpendicular to the metal reflector 2.

[0057] In this embodiment 1, the hexagonal honeycomb substrate 111 is made of aramid paper, with a relative permittivity of 2.5 and a loss angle of 0.005. The hexagonal honeycomb substrate 111 has a length of 3mm, a wall thickness of 0.13mm, and a height of 30mm. Resistive elements 112 are mounted on the inner wall of the hexagonal honeycomb substrate 111. The resistive elements 112 mounted on the sides are divided into four layers, each layer of resistive elements 112 being connected by metal copper sheets 113 mounted on the inner wall of the substrate. The metal copper sheets 113 are mounted on the inner wall of the aramid paper honeycomb substrate using circuit printing technology or adhesive bonding. They are rectangular in shape, with each inner wall metal copper sheet 113 divided into two rectangular regions, left and right, with lengths and widths of 1mm and 0.5mm respectively. Each inner wall uses rectangular metal copper sheets 113 for connecting the resistive elements 112, such as... Figure 1 As shown, adjacent resistor elements 112 in the same layer are connected in sequence to form a ring resistor network via copper sheets 113. The width of the rectangular copper sheet 113 near the inner wall edge of the substrate is connected to the inner wall edge. In the first ring resistor network 114, the bottom edge of the copper sheet 113 is 5mm away from the metal reflector 2. In the second ring resistor network 115, the bottom edge of the copper sheet 113 is 11mm away from the metal reflector 2. In the third ring resistor network 116, the bottom edge of the copper sheet 113 is 15mm away from the metal reflector 2. In the fourth ring resistor network 117, the bottom edge of the copper sheet 113 is 23mm away from the metal reflector 2. Resistor 112 is soldered with tin to the middle of two rectangular copper metal sheets 113 on the inner wall of the substrate. The resistance values ​​from bottom to top are as follows: the resistance of resistor 112 in the first ring resistor network 114 is R=200Ω, the resistance of resistor 112 in the second ring resistor network 115 is 2×R, the resistance of resistor 112 in the third ring resistor network 116 is 4×R, and the resistance of resistor 112 in the fourth ring resistor network 117 is 8×R.

[0058] Reference Figure 3 The reflection loss curve shown in this embodiment 1 indicates that the bandwidth of electromagnetic loss above -10dB is 1.72-18GHz.

[0059] Example 2

[0060] In Example 2, the honeycomb structure 1 is composed of several hexagonal electromagnetic wave absorbing units 11 arranged closely together, as shown in the figure. Figure 1As shown, the hexagonal electromagnetic wave absorbing unit 11 includes a hexagonal honeycomb substrate 111, a resistive element 112 loaded on the inner wall of the hexagonal electromagnetic wave absorbing unit 11, and a metal copper sheet 113 connected to the resistive element 112. During testing, a metal reflector 2 is set at the bottom near the first end 1111, and the electromagnetic wave incident direction is the radial direction perpendicular to the metal reflector 2.

[0061] In this embodiment 2, the hexagonal honeycomb substrate 111 is made of aramid paper, with a relative permittivity of 2.5 and a loss angle of 0.005. The hexagonal honeycomb substrate 111 has a length of 3mm, a wall thickness of 0.13mm, and a height of 30mm. Resistive elements 112 are mounted on the inner wall of the hexagonal honeycomb substrate 111. The resistive elements 112 mounted on the sides are divided into four layers, each layer of resistive elements 112 being connected by metal copper sheets 113 mounted on the inner wall of the substrate. The metal copper sheets 113 are mounted on the inner wall of the aramid paper honeycomb substrate using circuit printing technology or adhesive bonding. They are rectangular in shape, with each inner wall metal copper sheet 113 divided into two rectangular regions, left and right, with lengths and widths of 1mm and 0.5mm respectively. The rectangular metal copper sheets 113 used to connect the resistive elements 112 on each inner wall are as follows... Figure 1 As shown, adjacent resistor elements 112 in the same layer are connected in sequence to form a ring resistor network via copper sheets 113. The width of the rectangular copper sheet 113 near the inner wall edge of the substrate is connected to the inner wall edge. In the first ring resistor network 114, the bottom edge of the copper sheet 113 is 4mm away from the metal reflector 2. In the second ring resistor network 115, the bottom edge of the copper sheet 113 is 10mm away from the metal reflector 2. In the third ring resistor network 116, the bottom edge of the copper sheet 113 is 14mm away from the metal reflector 2. In the fourth ring resistor network 117, the bottom edge of the copper sheet 113 is 22mm away from the metal reflector 2. Resistor 112 is soldered with tin to the middle of two rectangular copper sheets 113 on the inner wall of the substrate. The resistance values ​​from bottom to top are as follows: the resistance of resistor 112 in the first ring resistor network 114 is R=150Ω, the resistance of resistor 112 in the second ring resistor network 115 is 2×R, the resistance of resistor 112 in the third ring resistor network 116 is 4×R, and the resistance of resistor 112 in the fourth ring resistor network 117 is 8×R.

[0062] In this embodiment 2, the bandwidth with electromagnetic losses above -10dB is 1.85-18GHz.

[0063] Example 3

[0064] In Example 3, the honeycomb structure 1 is composed of several hexagonal electromagnetic wave absorbing units 11 arranged closely together, as shown in the figure. Figure 1As shown, the hexagonal electromagnetic wave absorbing unit 11 includes a hexagonal honeycomb substrate 111, a resistive element 112 loaded on the inner wall of the hexagonal electromagnetic wave absorbing unit 11, and a metal copper sheet 113 connected to the resistive element 112. During testing, a metal reflector 2 is set at the bottom near the first end 1111, and the electromagnetic wave incident direction is the radial direction perpendicular to the metal reflector 2.

[0065] In this embodiment 3, the hexagonal honeycomb substrate 111 is made of aramid paper, with a relative permittivity of 2.5 and a loss angle of 0.005. The hexagonal honeycomb substrate 111 has a length of 3mm, a wall thickness of 0.13mm, and a height of 30mm. Resistive elements 112 are mounted on the inner wall of the hexagonal honeycomb substrate 111. The resistive elements 112 mounted on the sides are divided into four layers, each layer of resistive elements 112 being connected by metal copper sheets 113 mounted on the inner wall of the substrate. The metal copper sheets 113 are mounted on the inner wall of the aramid paper honeycomb substrate using circuit printing technology or adhesive bonding. They are rectangular in shape, with each inner wall metal copper sheet 113 divided into two rectangular regions, left and right, with lengths and widths of 1mm and 0.5mm respectively. The rectangular metal copper sheets 113 used to connect the resistive elements 112 on each inner wall are as follows... Figure 1 As shown, adjacent resistor elements 112 in the same layer are connected in sequence to form a ring resistor network via copper sheets 113. The width of the rectangular copper sheet 113 near the inner wall edge of the substrate is connected to the inner wall edge. In the first ring resistor network 114, the bottom edge of the copper sheet 113 is 6mm away from the metal reflector 2. In the second ring resistor network 115, the bottom edge of the copper sheet 113 is 12mm away from the metal reflector 2. In the third ring resistor network 116, the bottom edge of the copper sheet 113 is 16mm away from the metal reflector 2. In the fourth ring resistor network 117, the bottom edge of the copper sheet 113 is 24mm away from the metal reflector 2. Resistor 112 is soldered with tin to the middle of two rectangular copper sheets 113 on the inner wall of the substrate. The resistance values ​​from bottom to top are as follows: the resistance of resistor 112 in the first ring resistor network 114 is R=300Ω, the resistance of resistor 112 in the second ring resistor network 115 is 2×R, the resistance of resistor 112 in the third ring resistor network 116 is 4×R, and the resistance of resistor 112 in the fourth ring resistor network 117 is 8×R.

[0066] In this embodiment 3, the bandwidth of electromagnetic loss above -10dB is 2-18GHz.

[0067] Comparative Example 1

[0068] In Comparative Example 1, the honeycomb structure 1 is composed of several hexagonal electromagnetic wave absorbing units 11 arranged closely together, as shown in the figure. Figure 3As shown, the hexagonal electromagnetic wave absorbing unit 11 includes a hexagonal honeycomb substrate 111, a resistive element 112 loaded on the inner wall of the hexagonal electromagnetic wave absorbing unit 11, and a metal copper sheet 113 connected to the resistive element 112. During testing, a metal reflector 2 is set at the bottom near the first end 1111, and the electromagnetic wave incident direction is the radial direction perpendicular to the metal reflector 2.

[0069] In Comparative Example 1, the hexagonal honeycomb substrate 111 is made of aramid paper with a relative permittivity of 2.5 and a loss angle of 0.005. The hexagonal honeycomb substrate 111 has a length of 3 mm, a wall thickness of 0.13 mm, and a height of 30 mm. Resistive elements 112 are mounted on the inner wall of the hexagonal honeycomb substrate 111. The resistive elements 112 mounted on the sides are divided into three layers, each layer of resistive elements 112 being connected by metal copper sheets 113 mounted on the inner wall of the substrate. The metal copper sheets 113 are mounted on the inner wall of the aramid paper honeycomb substrate using circuit printing technology or adhesive bonding. They are rectangular in shape, with each inner wall metal copper sheet 113 divided into two rectangular regions, left and right, with lengths and widths of 1 mm and 0.5 mm, respectively. The rectangular metal copper sheets 113 used to connect the resistive elements 112 on each inner wall are as follows... Figure 1 As shown, adjacent resistor elements 112 in the same layer are connected sequentially by copper sheets 113 to form a ring resistor network. The width of the rectangular copper sheets 113 near the inner wall edge of the substrate is connected to the inner wall edge. In the first ring resistor network 114, the bottom edge of the copper sheets 113 is 5mm above the metal reflector 2; in the second ring resistor network 115, the bottom edge of the copper sheets 113 is 17mm above the metal reflector 2; and in the third ring resistor network 116, the bottom edge of the copper sheets 113 is 27mm above the metal reflector 2. The resistor element 112 is soldered with tin to the middle of the two rectangular copper sheets 113 on the inner wall of the substrate. The resistance values ​​from bottom to top are: R = 450Ω for the resistor element 112 in the first ring resistor network 114, 2 × R for the resistor element 112 in the second ring resistor network 115, and 4 × R for the resistor element 112 in the third ring resistor network 116.

[0070] Reference Figure 4 The reflection loss curves shown in Comparative Example 1 have a bandwidth of 2-18 GHz for electromagnetic losses above -8 dB.

[0071] By comparing the reflection loss curves of Examples 1-3 and Comparative Example 1, it can be seen that the ring resistor network in Examples 1-3 has four layers, and each layer of the ring resistor network is parallel to the plane where multiple electromagnetic wave absorption units 11 are located; the vertical distance between the first layer of the ring resistor network 114 and the first end 1111 is 4-6 mm; the vertical distance between the second layer of the ring resistor network 115 and the first end 1111 is 10-12 mm; the vertical distance between the third layer of the ring resistor network 116 and the first end 1111 is 14-16 mm; and the vertical distance between the fourth layer of the ring resistor network 117 and the first end 1111 is 22-24 mm. By defining the specific vertical distribution positions of the four-layer ring resistor network in the cellular substrate (first layer 4~6mm, second layer 10~12mm, third layer 14~16mm, fourth layer 22~24mm), an impedance matching structure with a precise spatial gradient in the electromagnetic wave incident direction was constructed. This structure can effectively expand the absorption bandwidth of electromagnetic waves, improve the stability of electromagnetic wave absorption performance, and enable the cellular structure to achieve high-efficiency electromagnetic wave absorption of more than -10dB in a wide frequency range of 1.72-18GHz, while taking into account structural compactness and process feasibility.

[0072] In embodiments 1-3 above, the resistance value of the resistor element 112 in the first-layer ring resistor network 114 is R, where R is 150~300Ω; the resistance value of the resistor element 112 in the second-layer ring resistor network 115 is 2R; the resistance value of the resistor element 112 in the third-layer ring resistor network 116 is 4R; and the resistance value of the resistor element 112 in the fourth-layer ring resistor network 117 is 8R. By limiting the resistance value of the resistor element 112 in the four-layer ring resistor network to increase geometrically (R, 2R, 4R, 8R), a continuous impedance gradient is formed in the electromagnetic wave incident direction, effectively widening the impedance matching bandwidth of the structure and enhancing the ohmic loss capability of electromagnetic waves in a wide frequency band (1.72-18GHz). Thus, while maintaining the lightweight and high strength of the structure, the stability and bandwidth coverage of electromagnetic wave absorption performance are significantly improved.

[0073] By comparing Examples 1-3 with Comparative Example 1, firstly, the number of resistor layers and gradient design in the Examples are superior. The Examples use four resistor layers with resistance values ​​increasing in the order R, 2R, 4R, and 8R, forming a more continuous impedance gradient. This facilitates the gradual entry of electromagnetic waves from free space into the absorber, reducing reflection. Comparative Example 1 uses only three resistor layers, resulting in a less smooth impedance change and stronger reflections in some frequency bands. Secondly, the copper sheets 113 are more densely arranged, forming a more uniform current path. In the Examples, the copper sheets 113 are more evenly distributed in the height direction (four layers), which helps electromagnetic waves undergo multiple reflections and attenuation within the honeycomb structure. In the Comparative Example, the copper sheets 113 are sparsely distributed (three layers), and electromagnetic waves are not sufficiently attenuated in some areas. Thirdly, the Examples exhibit stronger low-frequency absorption capability. Example 1 achieves -10dB at 1.72GHz, while the Comparative Example only achieves -8dB at 2GHz. This demonstrates that the structure of the Examples has better impedance matching in the low-frequency band, effectively absorbing longer wavelength electromagnetic waves. Fourthly, the embodiments exhibit strong process controllability. They employ discrete resistor elements 112, ensuring precise and controllable resistance values, thus avoiding the instability of square resistance encountered in processes like those using patterned resistive films. While the comparative examples also use resistors, their fewer layers and insufficient gradient lead to a decrease in overall performance. Embodiments 1-3, through four layers of gradient resistors, a reasonable arrangement of copper sheets, and precise resistance control, achieve electromagnetic wave absorption performance exceeding -10dB within a wide frequency band of 1.72-18GHz, significantly outperforming the three-layer structure of Comparative Example 1. This design achieves a good balance between wide bandwidth, strong absorption, structural stability, and process controllability, making it suitable for high-performance stealth structures, electromagnetic compatibility, and other military and civilian applications.

[0074] Based on the same inventive concept, this embodiment of the invention also provides an anti-interference device, the outer surface of which is covered with the aforementioned honeycomb structure. By attaching the honeycomb structure to the outer surface of the anti-interference device, the device possesses excellent electromagnetic wave absorption capability in a wide frequency range of 1.72-18GHz, effectively suppressing external electromagnetic interference. Simultaneously, this structure is lightweight, high-strength, and technologically stable, improving the reliability and performance of the device in complex electromagnetic environments.

[0075] Based on the same inventive concept, this embodiment of the invention also provides an application of the above-mentioned cellular structure in anti-interference equipment. Applying the cellular structure to anti-interference equipment can effectively suppress electromagnetic interference by utilizing its wide bandwidth (1.72-18GHz) and high absorption (below -10dB) characteristics, thereby improving the stability and reliability of the equipment in complex electromagnetic environments. Furthermore, due to its lightweight structure and controllable manufacturing process, it is easy to integrate into the surface of various anti-interference equipment, achieving efficient and broadband electromagnetic wave absorption and protection.

[0076] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. This disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. Thus, if these modifications and variations of the invention fall within the scope of the invention and its equivalents, the invention is also intended to include these modifications and variations.

Claims

1. A honeycomb structure, characterized in that, include: Multiple electromagnetic wave absorbing units arranged sequentially on the same plane; Each electromagnetic wave absorbing unit includes: a hexagonal honeycomb substrate, multiple resistive elements layered on the inner wall of the hexagonal honeycomb substrate, and multiple copper metal sheets disposed on the inner wall of the hexagonal honeycomb substrate; The adjacent resistive elements on the same layer are connected in sequence through the copper sheet to form a ring-shaped resistive network; The electromagnetic wave absorption unit includes a first end and a second end, and the resistance value of the resistive element in the multilayer ring resistor network increases layer by layer from the first end to the second end.

2. The honeycomb structure according to claim 1, characterized in that, The ring resistor network has four layers, and each layer of the ring resistor network is parallel to the plane in which the multiple electromagnetic wave absorption units are located. The vertical distance between the first layer of the ring resistor network and the first end is 4~6mm; The vertical distance between the second layer of the ring resistor network and the first end is 10~12mm; The vertical distance between the third layer of the ring resistor network and the first end is 14~16mm; The vertical distance between the fourth layer of the ring resistor network and the first end is 22~24mm.

3. The honeycomb structure according to claim 2, characterized in that, The resistance of the resistor element in the first layer of the ring resistor network is R, where R is 150~300Ω; The resistance of the resistor element in the second-layer ring resistor network is 2R; The resistance of the resistor element in the third-layer ring resistor network is 4R; The resistance of the resistor element in the fourth-layer ring resistor network is 8R.

4. The honeycomb structure according to any one of claims 1 to 3, characterized in that, The hexagonal honeycomb substrate is made of aramid paper; the relative permittivity of the hexagonal honeycomb substrate is 2.5, and the loss angle is 0.

005.

5. The honeycomb structure according to claim 4, characterized in that, The hexagonal honeycomb substrate has a side length of 3mm, a wall thickness of 0.13mm, and a height of 30mm.

6. The honeycomb structure according to claim 4, characterized in that, The copper sheet is rectangular and is disposed on the inner wall of the connection between adjacent sides of the hexagonal honeycomb substrate. Each copper sheet is 1 mm long and 0.5 mm wide.

7. The honeycomb structure according to claim 6, characterized in that, The copper sheet is mounted on the inner wall of the hexagonal honeycomb substrate using circuit printing technology or adhesive bonding.

8. The honeycomb structure according to claim 4, characterized in that, The resistive element is soldered between the copper sheets using tin.

9. An anti-interference device, characterized in that, The outer surface of the anti-interference device is attached with a honeycomb structure as described in any one of claims 1 to 8.

10. The application of a cellular structure as described in any one of claims 1 to 8 in an anti-interference device.

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