Large-angle wave-transparent metamaterial antenna housing
The A-layer structure, designed with two microstructures, solves the problem of deteriorated transmission characteristics of the radome at large incident angles, achieving wideband wave transmission and low radar cross section, expanding the working coverage of the antenna, and meeting the stealth requirements of high-performance communication systems.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-31
- Publication Date
- 2026-03-13
AI Technical Summary
Existing radomes exhibit drastic deterioration in transmission characteristics at large incident angles, failing to achieve broadband transmission and possessing a high radar cross section, making it difficult to meet the requirements of high-performance communication systems.
The design employs a two-layer microstructure, consisting of an A-layer sandwich structure composed of a band-stop microstructure layer and a dielectric layer. Through symmetrical conformal coupling units and the arrangement of microstructures, it achieves fast cutoff outside the frequency band and broadband wave transmission within the frequency band.
Achieving wideband wave transmission at large incident angles reduces radar cross section, expands antenna operating coverage, and meets the stealth requirements of high-performance communication systems.
Smart Images
Figure CN121663181A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of metamaterials, and more specifically, to a wide-angle transparent metamaterial radome. Background Technology
[0002] Radomes are one of the most commonly used and important components in radar communication systems. With the trend towards wider bandwidth in communication systems, research on broadband radomes is increasingly being strengthened. While designing the broadband characteristics of a frequency selective surface (FSS), it is necessary to ensure the stability of its operating performance across the entire frequency band under different incident angles to improve the overall performance of the antenna system. For traditional FSS radomes, their frequency response is often highly sensitive to the incident angle of electromagnetic waves; as the incident angle increases, the transmission characteristics deteriorate sharply, achieving only a narrow operating bandwidth at large incident angles.
[0003] Existing radome design methods mainly include geometry optimization, material selection, and structural layering. Geometry optimization alone is insufficient to overcome the losses and phase shifts caused by large incident angles. Material selection and layered design can increase bandwidth to some extent, but at large incident angles, the impedance differences and phase delays between different layers lead to a sharp deterioration in transmission characteristics, making it impossible to achieve broadband transmission at large incident angles. Summary of the Invention
[0004] To address the problems in related technologies, this invention proposes a large-angle transparent metamaterial radome, which solves the technical problems of having broadband in-band wave transmission at large incident angles and fast out-of-band cutoff to reduce the overall radar cross section (RCS).
[0005] This invention provides a large-angle transparent metamaterial radome, comprising: a first prepreg layer, a second prepreg layer, a core material layer, a first microstructure layer, and a second microstructure layer; the stacking order of the structures of the radome from the outside to the inside is the first microstructure layer, the first prepreg layer, the core material layer, the second prepreg layer, and the second microstructure layer; wherein, the first microstructure layer and the second microstructure layer are both band-resistive microstructure layers.
[0006] Preferably, the radome further includes a third prepreg layer and a fourth prepreg layer, and the stacking order of the structures of the radome from the outside to the inside is as follows: third prepreg layer, first microstructure layer, first prepreg layer, core material layer, second prepreg layer, second microstructure layer and fourth prepreg layer.
[0007] Preferably, the first microstructure layer and the second microstructure layer are completely identical.
[0008] Preferably, both the first microstructure layer and the second microstructure layer include a substrate and a first conductive geometric structure and six second conductive geometric structures disposed on the substrate, wherein the six second conductive geometric structures are identical. The first conductive geometric structure is in the shape of a regular hexagonal ring, and the six second conductive geometric structures are connected end to end in sequence to form an approximate hexagonal ring; the six second conductive geometric structures are respectively disposed on the six sides of the first conductive geometric structure. Each second conductive geometry includes a first straight segment, multiple identical raised curve segments, and a bent curve segment. The multiple raised curve segments are arranged sequentially, one end to the other, and each of the multiple raised curve segments is perpendicularly arranged on the corresponding side of the first conductive geometry. A first gap is formed between any two adjacent raised curve segments, and the shape of each raised curve segment is exactly the same as the shape of a rectangular wave in the positive half-cycle. One end of the plurality of raised curved segments is perpendicularly connected to the first straight segment, and the other end of the plurality of raised curved segments forms a second gap with the bent curved segment; the bent curved segment includes a fixed straight segment and a free straight segment, one end of the fixed straight segment is perpendicularly disposed on the corresponding side of the first conductive geometry, and the other end of the fixed straight segment is perpendicularly connected to the free straight segment.
[0009] Preferably, the first gap formed between any two adjacent convex curve segments is exactly the same.
[0010] Preferably, the structure formed by the third prepreg layer, the first microstructure layer, and the first prepreg layer is symmetrically arranged with respect to the core material layer, as is the structure formed by the fourth prepreg layer, the second microstructure layer, and the second prepreg layer.
[0011] Preferably, any two adjacent layers among the third prepreg layer, the first microstructure layer, the first prepreg layer, the core layer, the second prepreg layer, the second microstructure layer, and the fourth prepreg layer are bonded together using an adhesive film.
[0012] Preferably, the dielectric constant of the first prepreg layer, the second prepreg layer, the third prepreg layer, and the fourth prepreg layer is 3.3, and the loss tangent is 0.005; the dielectric constant of the adhesive film is 3.2, and the loss tangent is 0.007; the dielectric constant of the core layer is 1.12, and the loss tangent is 0.068.
[0013] Preferably, the materials of the first prepreg layer, the second prepreg layer, the third prepreg layer and the fourth prepreg layer all include glass fiber prepreg or quartz fiber prepreg, and the material of the core layer includes PMI foam.
[0014] The beneficial effects of this invention are as follows: The large-angle transparent metamaterial radome described in this embodiment of the invention adopts a two-layer microstructure design. The upper and lower band-stop microstructures (i.e., the first microstructure layer and the second microstructure layer) achieve rapid cutoff outside the operating frequency band to reduce the radar cross section (RCS) of the radome. The radome can also achieve broadband wave transmission within the operating frequency band, thereby meeting the requirements of high-performance communication detection systems and stealth. Attached Figure Description
[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0016] Figure 1 This is a schematic diagram of the structure of a large-angle transparent metamaterial radome according to an embodiment of the present invention.
[0017] Figure 2 for Figure 1 The diagram shows the structure of the microstructure layer.
[0018] Figure 3 for Figure 1 The diagram shows the transmittance curve of the radome in TM mode.
[0019] Figure 4 for Figure 1 The diagram shows the transmittance curve of the radome in TE mode. Detailed Implementation
[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the scope of protection of the present invention.
[0021] This invention proposes a large-angle transparent metamaterial radome, which aims to achieve broadband in-band wave transmission at large incident angles and rapid out-of-band cutoff to reduce the overall radar cross section (RCS) of the radome, thereby meeting the requirements of high-performance communication detection systems and stealth.
[0022] Figure 1 This is a schematic diagram of the structure of a large-angle transparent metamaterial radome 100 according to an embodiment of the present invention. Figure 1As shown, the large-angle transparent metamaterial radome 100 includes a first prepreg layer 12, a second prepreg layer 15, a core material layer 14, a first microstructure layer 10, and a second microstructure layer 16. The stacking order of the structures of the radome 100 from the outside to the inside is the first microstructure layer 10, the first prepreg layer 12, the core material layer 14, the second prepreg layer 15, and the second microstructure layer 16; wherein, the first microstructure layer 10 and the second microstructure layer 16 are both band-resistive microstructure layers.
[0023] Furthermore, considering the wideband characteristics and out-of-band fast cutoff characteristics of the radome 100, this invention employs an A-layer design, which includes two microstructure layers and a dielectric layer. The dielectric layer includes a prepreg layer (dielectric constant 3.3, loss tangent 0.005), an adhesive film (dielectric constant 3.2, loss tangent 0.007), and a PMI (dielectric constant 1.12, loss tangent 0.068). Figure 1 As shown, the large-angle transparent metamaterial radome 100 also includes a third prepreg layer 18 and a fourth prepreg layer 19. The stacking order of the structures of the radome 100 from the outside to the inside is as follows: third prepreg layer 18, first microstructure layer 10, first prepreg layer 12, core material layer 14, second prepreg layer 15, second microstructure layer 16 and fourth prepreg layer 19.
[0024] In this embodiment, the materials of the first prepreg layer 12, the second prepreg layer 15, the third prepreg layer 18 and the fourth prepreg layer 19 are including but not limited to glass fiber prepreg or quartz fiber prepreg, and the material of the core layer 14 is including but not limited to PMI foam.
[0025] The first microstructure layer 10 and the second microstructure layer 16 are completely identical.
[0026] Any two adjacent layers among the third prepreg layer 18, the first microstructure layer 10, the first prepreg layer 12, the core layer 14, the second prepreg layer 15, the second microstructure layer 16, and the fourth prepreg layer 19 are bonded together with an adhesive film.
[0027] In this embodiment, the dielectric constants of the first prepreg layer 12, the second prepreg layer 15, the third prepreg layer 18, and the fourth prepreg layer 19 are all 3.3, and the loss tangent is 0.005. The dielectric constant of the adhesive film is 3.2, and the loss tangent is 0.007. The dielectric constant of the core layer 14 is 1.12, and the loss tangent is 0.068.
[0028] In this embodiment, the thickness of the third prepreg layer 18 is 0.35 mm, the thickness of the first prepreg layer 12 is 0.2 mm, the thickness of the second prepreg layer 15 is 0.2 mm, and the thickness of the fourth prepreg layer 19 is 0.35 mm. The thickness of the core layer 14 is 4 mm.
[0029] like Figure 2 As shown, in this embodiment, both the first microstructure layer 10 and the second microstructure layer 16 include a substrate and a first conductive geometry 120 and six second conductive geometry 140 disposed on the substrate. The six second conductive geometry 140 are identical.
[0030] The substrate material includes, but is not limited to, PI film.
[0031] The first conductive geometric structure 120 is in the shape of a regular hexagonal ring. Six second conductive geometric structures 140 are connected end to end to form an approximate hexagonal ring. The six second conductive geometric structures 140 are respectively disposed on the six sides of the first conductive geometric structure 120.
[0032] Each second conductive geometry 140 includes a first straight segment 142, multiple identical raised curve segments 144, and bent curve segments 146. The multiple raised curve segments 144 are arranged sequentially, one end to the other, and the multiple raised curve segments 144 are all vertically arranged on the corresponding sides of the first conductive geometry 120. A first gap is formed between any two adjacent raised curve segments 144, and the shape of each raised curve segment 144 is exactly the same as the shape of a rectangular wave in the positive half-cycle.
[0033] One end of a plurality of raised curved segments 144 is perpendicularly connected to the first straight segment 142, and the other end of the plurality of raised curved segments 144 forms a second gap with the bent curved segment 146. The bent curved segment 146 includes a fixed straight segment and a free straight segment. One end of the fixed straight segment is perpendicularly disposed on the corresponding side of the first conductive geometry 120, and the other end of the fixed straight segment is perpendicularly connected to the free straight segment.
[0034] In this embodiment, the number of the plurality of raised curve segments 144 includes, but is not limited to, three; the first gap formed between any two adjacent raised curve segments 144 is exactly the same.
[0035] In this embodiment, the side length c of the first conductive geometry 120, which is a regular hexagonal ring, is 3.9 mm. The linewidth g of the first conductive geometry 120 is 0.22 mm. The linewidth a of the second conductive geometry 140 is 0.09 mm. The length b of the free straight segment of the bent curve segment 146 is 0.75 mm. The length d of the first conductive geometry 120, which is a regular hexagonal ring, passing through the center diagonal is 7.8 mm. The shape of each raised curve segment 144 is exactly the same as the shape of a rectangular wave in the positive half-cycle. The length f of the high-level continuous line segment of the raised curve segment 144 is 0.42 mm, and the length e of the line segment of the raised curve segment 144 rising from zero level to high level is 0.76 mm.
[0036] Optionally, in other embodiments, both the first microstructure layer and the second microstructure layer include a substrate and a first conductive geometric structure and four second conductive geometric structures disposed on the substrate, wherein the four second conductive geometric structures are identical.
[0037] The first conductive geometric structure is in the shape of a regular quadrilateral ring, and the four second conductive geometric structures are connected end to end in sequence to form an approximate quadrilateral ring; the four second conductive geometric structures are respectively disposed on the four sides of the first conductive geometric structure.
[0038] Each second conductive geometry includes a first straight segment, multiple identical raised curve segments, and a bent curve segment. The multiple raised curve segments are arranged sequentially, one end to the other, and each of the multiple raised curve segments is perpendicularly arranged on the corresponding side of the first conductive geometry. A first gap is formed between any two adjacent raised curve segments, and the shape of each raised curve segment is exactly the same as the shape of a rectangular wave in the positive half-cycle.
[0039] One end of the plurality of raised curved segments is perpendicularly connected to the first straight segment, and the other end of the plurality of raised curved segments forms a second gap with the bent curved segment; the bent curved segment includes a fixed straight segment and a free straight segment, one end of the fixed straight segment is perpendicularly disposed on the corresponding side of the first conductive geometry, and the other end of the fixed straight segment is perpendicularly connected to the free straight segment.
[0040] Traditional single-layer FSS in existing technologies presents a contradiction in achieving wide-angle stability and wideband characteristics. Increasing the complexity of microstructure units to expand bandwidth often worsens wide-angle stability; while pursuing wide-angle stability usually requires sacrificing bandwidth or increasing the number of structural layers, leading to design complexity, increased cost, and increased insertion loss.
[0041] The innovations of the radome 100 of this invention compared to the prior art are as follows: The resonance principle of the radome 100 is that each microstructure unit is equivalent to an LC resonant circuit; the radome 100 provides an FSS array based on symmetrical conformal coupling units, the main unit of which is a multi-layered nested microstructure; by setting coupling structures of microstructures of different shapes and / or different sizes in different layers, or by setting coupling structures of microstructures of the same shape and size in different layers, and by forming additional parasitic resonant loops through edge field coupling, the bandwidth is expanded; and the hexagonal arrangement of the microstructures has better wide-angle stability. In other optional embodiments, the quadrilateral arrangement of the microstructures can also have good wide-angle stability.
[0042] Figure 3 for Figure 1 The diagram shows the transmittance curve of the radome in TM mode. Figure 4 for Figure 1The diagram shows the transmittance curve of the radome in TE mode. Simulation results are as follows. Figure 3 and Figure 4 As shown in Table 1, the transmission statistics results are presented in the table.
[0043] Table 1
[0044] As can be seen from the results shown in Table 1 above, the embodiments of the present invention disclose a broadband transparent metamaterial radome 100 with a large incident angle. The radome 100 of the present invention adopts a two-layer microstructure design with an A-layer sandwich, and the upper and lower layers are band-resistive microstructures 10 and 16 (i.e., Figure 1 The first microstructure layer 10 and the second microstructure layer 16 shown achieve out-of-band fast cutoff, reducing the RCS of the radome 100. Simulation calculations, as shown in Table 1 above, demonstrate that in both TE and TM modes, the radome 100 achieves an average transmittance greater than 80% within the operating frequency band of 0-1 GHz (specifically, in TM mode, the radome 100 even achieves an average transmittance greater than 80% within the operating frequency band of 0-4 GHz); and in both TE and TM modes, the radome 100 achieves fast cutoff outside the operating frequency band of 8-18 GHz. The radome 100 of this invention does not limit the incident angle of electromagnetic waves and still exhibits excellent transmittance within the operating frequency band and fast cutoff performance outside the operating frequency band for a relatively large range of incident angles (e.g., 0°~60°).
[0045] It should be noted that there is currently no quantitative definition of high transmittance in scientific research and engineering, and this concept is indeed difficult to define numerically. Of course, generally speaking, and without other limiting conditions, a transmittance higher than -1dB (80%) is generally considered high transmittance.
[0046] For specific examples, such as Figure 3 and Figure 4 As shown, when the incident angle is 60°, the radome 100 exhibits the following characteristics: 1) Transmission zone: The bandwidth of the transmission zone with a transmittance greater than 80% in TE mode is 1 GHz, and the bandwidth of the transmission zone with a transmittance greater than 80% in TM mode is 4 GHz; 2) Cutoff zone: Both TE and TM modes can achieve an out-of-band cutoff of more than -5dB in the 8-18 GHz frequency band. This means that the antenna coverage range can be effectively expanded while maintaining a low RCS, ensuring efficient communication of the antenna system.
[0047] This invention proposes a large-angle broadband transparent radome design based on microstructure design (i.e., large-angle transparent metamaterial radome 100), which is mainly applied in satellite communication, radar systems, aerospace radomes, wireless sensor networks, and electromagnetic compatibility. Its advantage lies in maintaining a wide bandwidth even at large incident angles, effectively expanding the antenna's operating coverage and thus improving the overall performance of the antenna system. Furthermore, in military applications, considering stealth requirements, the radome 100 of this invention is designed with fast out-of-band cutoff while maintaining effective in-band bandpass to meet stealth requirements.
[0048] When designing a wideband transmission antenna radome 100 at large incident angles, traditional transmission materials and methods often lead to poor impedance matching, enhanced multiple reflections and interference effects, and the excitation of higher-order modes as the incident angle increases. These factors work together to cause a sharp decline in transmission performance. Therefore, it is necessary to precisely control the electromagnetic properties of the material and adopt a novel complex structural design to achieve consistent high transmittance at large incident angles over a wide bandwidth. Simulation experiments have proven that the technical solution of the radome 100 of this invention has achieved significant technical effects (i.e., it achieves wide-angle stability and wideband characteristics) compared with the prior art, overcoming the defects of the prior art.
[0049] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A large-angle wave-transparent metamaterial radome, characterized in that, include: The antenna radome consists of a first prepreg layer, a second prepreg layer, a core material layer, a first microstructure layer, and a second microstructure layer. The stacking order of the structures from the outside to the inside is as follows: first microstructure layer, first prepreg layer, core material layer, second prepreg layer, and second microstructure layer. The first and second microstructure layers are both band-resistive microstructure layers.
2. The radome according to claim 1, characterized in that, It also includes a third prepreg layer and a fourth prepreg layer. The stacking order of the structures of the radome from the outside to the inside is as follows: third prepreg layer, first microstructure layer, first prepreg layer, core material layer, second prepreg layer, second microstructure layer and fourth prepreg layer.
3. The radome according to claim 2, characterized in that, The first microstructure layer and the second microstructure layer are completely identical.
4. The radome according to claim 3, characterized in that, Both the first microstructure layer and the second microstructure layer include a substrate and a first conductive geometric structure and six second conductive geometric structures disposed on the substrate, wherein the six second conductive geometric structures are identical. The first conductive geometric structure is in the shape of a regular hexagonal ring, and the six second conductive geometric structures are connected end to end in sequence to form an approximate hexagonal ring; the six second conductive geometric structures are respectively disposed on the six sides of the first conductive geometric structure. Each second conductive geometry includes a first straight segment, multiple identical raised curve segments, and a bent curve segment. The multiple raised curve segments are arranged sequentially, one end to the other, and each of the multiple raised curve segments is perpendicularly arranged on the corresponding side of the first conductive geometry. A first gap is formed between any two adjacent raised curve segments, and the shape of each raised curve segment is exactly the same as the shape of a rectangular wave in the positive half-cycle. One end of the plurality of raised curved segments is perpendicularly connected to the first straight segment, and the other end of the plurality of raised curved segments forms a second gap with the bent curved segment; the bent curved segment includes a fixed straight segment and a free straight segment, one end of the fixed straight segment is perpendicularly disposed on the corresponding side of the first conductive geometry, and the other end of the fixed straight segment is perpendicularly connected to the free straight segment.
5. In the radome according to claim 4, the first gap formed between any two adjacent convex curve segments is exactly the same.
6. The radome according to claim 3, characterized in that, Both the first microstructure layer and the second microstructure layer include a substrate and a first conductive geometric structure and four second conductive geometric structures disposed on the substrate, wherein the four second conductive geometric structures are identical. The first conductive geometric structure is in the shape of a regular quadrilateral ring, and the four second conductive geometric structures are connected end to end in sequence to form an approximate quadrilateral ring; the four second conductive geometric structures are respectively disposed on the four sides of the first conductive geometric structure. Each second conductive geometry includes a first straight segment, multiple identical raised curve segments, and a bent curve segment. The multiple raised curve segments are arranged sequentially, one end to the other, and each of the multiple raised curve segments is perpendicularly arranged on the corresponding side of the first conductive geometry. A first gap is formed between any two adjacent raised curve segments, and the shape of each raised curve segment is exactly the same as the shape of a rectangular wave in the positive half-cycle. One end of the plurality of raised curved segments is perpendicularly connected to the first straight segment, and the other end of the plurality of raised curved segments forms a second gap with the bent curved segment; the bent curved segment includes a fixed straight segment and a free straight segment, one end of the fixed straight segment is perpendicularly disposed on the corresponding side of the first conductive geometry, and the other end of the fixed straight segment is perpendicularly connected to the free straight segment.
7. The radome according to claim 2, characterized in that, The structures formed by the third prepreg layer, the first microstructure layer, and the first prepreg layer are symmetrically arranged with respect to the core material layer, as are the structures formed by the fourth prepreg layer, the second microstructure layer, and the second prepreg layer.
8. The radome according to claim 2, characterized in that, Any two adjacent layers among the third prepreg layer, the first microstructure layer, the first prepreg layer, the core layer, the second prepreg layer, the second microstructure layer, and the fourth prepreg layer are bonded together with an adhesive film.
9. The radome according to claim 8, characterized in that, The dielectric constants of the first, second, third, and fourth prepreg layers are all 3.3, and the loss tangent is 0.005; the dielectric constants of the adhesive film are all 3.2, and the loss tangent is 0.007; the dielectric constant of the core layer is 1.12, and the loss tangent is 0.
068.
10. The radome according to claim 2, characterized in that, The materials of the first prepreg layer, the second prepreg layer, the third prepreg layer and the fourth prepreg layer all include glass fiber prepreg or quartz fiber prepreg, and the material of the core layer includes PMI foam.