Spatially multiplexed strongly absorbing electromagnetic wave absorber

Abstract

The application discloses a kind of space multiplexing strong absorption electromagnetic wave-absorbing metamaterial, belong to electromagnetic wave-absorbing technical field.The material includes skin, wave-absorbing functional layer and strong reflection backboard from top to bottom in Z direction;Wave-absorbing functional layer includes lossy dielectric hollow cylinder I, lossy dielectric hollow cylinder II and lossy dielectric hollow cylinder III in turn from outside to inside in XOY plane;Lossy dielectric hollow cylinder I is sequentially provided with electromagnetic super surface I, electromagnetic super surface II and electromagnetic super surface III in Z direction, lossy dielectric hollow cylinder II is sequentially provided with electromagnetic super surface IV and electromagnetic super surface V in Z direction, and lossy dielectric hollow cylinder III is sequentially provided with electromagnetic super surface VI and electromagnetic super surface VII in Z direction.The application is designed by three layers of nested hollow cylinder, the frequency band with reflection coefficient lower than-30 dB is not less than 4.0-14.8 GHz when vertical incidence, the frequency band with reflection coefficient lower than-20 dB is not less than 3.0-15.8 GHz, and still keep good absorption performance under large oblique incidence angle.

Description

Technical Field

[0001] This invention belongs to the field of electromagnetic wave absorption technology, specifically relating to a space-reusable, strongly absorbing electromagnetic wave metamaterial. Background Technology

[0002] The development of information technology and the demands of the electromagnetic compatibility field have placed higher requirements on electromagnetic absorbing materials. Ideal high-performance absorbing materials need to simultaneously achieve ultra-wide effective absorption bandwidth, strong absorption characteristics, maintain stable performance under large oblique incidence angles, and have the advantages of simple structure, low cost, and lightweight engineering applications.

[0003] While existing two-dimensional planar absorbing metasurfaces offer flexible configurations and convenient design, allowing for optimized impedance matching through multi-layer stacking to achieve broadband and strong absorption performance, this structural form introduces greater manufacturing complexity. Furthermore, due to the constrained resonant loss mechanism, the deep absorption bandwidth narrows rapidly with increasing incident angle, essentially losing effective deep absorption capability at a large incident angle of 75°, making it unsuitable for applications requiring omnidirectional stealth and complex electromagnetic environments.

[0004] While existing three-dimensional absorbing structures can broaden the absorption bandwidth to some extent, they still cannot effectively overcome the technical bottleneck of broadband deep absorption: solid three-dimensional structures can ensure a certain absorption intensity, but their surface density is too high, resulting in insufficient lightweight effect; honeycomb absorbing materials, as a typical representative of hollow three-dimensional structures, employ multi-layer honeycomb structure designs or matrix impregnation with absorbing agents to achieve strong absorption performance, but fail to fundamentally meet the issues of simplifying the manufacturing process and extending the environmental reliability of the structure for long-term service, and cannot simultaneously meet the multiple performance requirements of broadband deep absorption, lightweight, and wide-angle stability.

[0005] Therefore, developing three-dimensional absorbing metamaterials that are component-free, simple to manufacture, lightweight, and possess both ultra-wideband strong absorption and large-angle stability is a key research direction in this field. Summary of the Invention

[0006] The purpose of this invention is to provide a spatially reusable, strongly absorbing electromagnetic wave-absorbing metamaterial. Its structural unit adopts a multi-layered, concentrically nested hollow column structure. By loading different metasurface loss functional layers onto the outer surface of each cuboid column, excellent impedance matching, strong absorption characteristics, and a large oblique incidence angle are simultaneously achieved. This meets the current application requirements for three-dimensional absorbing metamaterials that are component-free, simple to manufacture, lightweight, and possess both ultra-wideband strong absorption and large-angle stability.

[0007] This invention provides a spatially reusable, strongly absorbing electromagnetic wave-absorbing metamaterial. In the XYZ three-dimensional coordinate system, from top to bottom in the Z direction, it includes a skin, a wave-absorbing functional layer, and a strong reflective backplate. In the XOY plane, the wave-absorbing functional layer sequentially includes, from outside to inside, a lossy dielectric hollow cylinder I, a lossy dielectric hollow cylinder II, and a lossy dielectric hollow cylinder III. Electromagnetic metasurfaces I, II, and III are sequentially arranged in the Z direction of the lossy dielectric hollow cylinder I; electromagnetic metasurfaces IV and V are sequentially arranged in the Z direction of the lossy dielectric hollow cylinder II; and electromagnetic metasurfaces VI and VII are sequentially arranged in the Z direction of the lossy dielectric hollow cylinder III.

[0008] Preferably, the absorbing metamaterials are arranged periodically in the XOY plane, with a period of 10.0~30.0 mm. The size of the material is determined according to the actual needs of the application scenario.

[0009] Preferably, the skin, lossy dielectric hollow cylinder I, lossy dielectric hollow cylinder II, and lossy dielectric hollow cylinder III are all materials with certain dielectric loss or magnetic loss characteristics, such as PLA, PET, Carbon / Glass Fiber Reinforced PLA, magnetic metal micropowder doped PPS, glass fiber board, or aramid paper, etc., with a relative permittivity ranging from 1.5 to 15.0, a relative permeability ranging from 1.0 to 15.0, and a thickness of 0.1 to 5.0 mm; the height of lossy dielectric hollow cylinder I, lossy dielectric hollow cylinder II, and lossy dielectric hollow cylinder III are all 10.0 to 35.0 mm.

[0010] Preferably, the electromagnetic metasurface I is a rectangular ring resistive film attached to the inner or outer wall of the hollow cylinder I of the lossy medium, arranged along the Z-axis direction. The length of the rectangular ring is 10.0-30.0 mm, the width is 2.0-10.0 mm, the line width is 0.5-4.5 mm, and the sheet resistance is 10-1000 Ω / sq.

[0011] Preferably, the electromagnetic metasurface II is a ring structure attached to the inner or outer wall of the hollow cylinder I of the lossy medium, arranged along the Z-axis. The ring structure is composed of a low sheet resistance resistive film with a linewidth of 0.5-4.0 mm and a sheet resistance of 0.1-30 Ω / sq. Multiple high sheet resistance rectangular resistive films I are uniformly distributed on the ring structure. The length and width of the rectangular resistive film I are both 0.5-5.0 mm, and the sheet resistance is 30-1000 Ω / sq.

[0012] Preferably, the electromagnetic metasurface III is a discontinuous resistive film line attached to the inner or outer wall of the hollow cylinder I of the lossy medium, arranged along the Z-axis direction. The linewidth of the resistive film line is 0.5-4.0 mm, and the sheet resistance is 0.1-30 Ω / sq. Multiple high sheet resistance rectangular resistive films II are uniformly distributed on the resistive film line. The length and width of the rectangular resistive films II are both 0.5-5.0 mm, and the sheet resistance is 30-1000 Ω / sq.

[0013] The electromagnetic metasurface IV consists of multiple rectangular annular resistive films attached to the inner wall or the upper half of the outer wall of the hollow cylinder II containing the lossy medium, arranged along the Z-axis. The rectangular annular resistive films achieve local impedance adjustment by connecting resistive film lines of different linewidths. The linewidth of the annular resistive films is 0.5-4.0 mm, and the sheet resistance is 30-1000 Ω / sq.

[0014] The electromagnetic metasurface V is a complete resistive film attached to the lower half of the inner or outer wall of the hollow cylinder II of the lossy medium, and is set along the Z-axis. The sheet resistance of the complete resistive film is 30-1000 Ω / sq.

[0015] Electromagnetic metasurface VI is a rectangular ring resistive film attached end to end to the upper half of the inner or outer wall of the hollow cylinder III of the lossy medium, arranged along the Z-axis. The length of the rectangular ring resistive film is 10.0-30.0 mm, the width is 2.0-10.0 mm, the linewidth is 0.5-4.5 mm, and the sheet resistance is 10-1000 Ω / sq.

[0016] Electromagnetic metasurface VII is a ring structure attached to the lower half of the inner or outer wall of the hollow cylinder III of the lossy medium, arranged along the Z-axis. The ring structure is composed of low sheet resistance resistive films with a linewidth of 0.5-4.0 mm and a sheet resistance of 0.1-30 Ω / sq. Multiple high sheet resistance rectangular resistive films III are uniformly distributed on the ring structure. The length and width of the rectangular resistive films III are both 0.5-5.0 mm, and the sheet resistance is 30-1000 Ω / sq.

[0017] Preferably, the high-reflectivity backplate is made of a highly conductive material, such as copper foil, carbon fiber plate, silicon carbide fiber plate, etc.

[0018] Preferably, electromagnetic metasurfaces I, II, III, IV, V, VI, and VII can be prepared by processes such as screen printing and inkjet printing.

[0019] Preferably, the hollow cylinder I, hollow cylinder II, and hollow cylinder III of the damaged medium are prepared by 3D printing or by processes such as engraving, molding, or lamination bonding and stretching.

[0020] Working principle

[0021] 1. The strong absorption performance of the spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial of the present invention is mainly obtained through the spatially reused impedance matching optimization design of 3-electromagnetic metasurface I, 4-electromagnetic metasurface II and 5-electromagnetic metasurface III, 9-electromagnetic metasurface IV and 11-electromagnetic metasurface V, 12-electromagnetic metasurface VI and 14-electromagnetic metasurface VII. 3-electromagnetic metasurface I is a low-frequency absorption compensation layer, 4-electromagnetic metasurface II is a low-frequency strong absorption layer, and 5-electromagnetic metasurface III is a mid-frequency and high-frequency impedance adjustment layer; 9-electromagnetic metasurface IV is a full-band absorption compensation layer and impedance adjustment layer, 11-electromagnetic metasurface V is a mid-to-high-frequency absorption compensation layer; 12-electromagnetic metasurface VI is a full-band absorption compensation layer and impedance adjustment layer, and 14-electromagnetic metasurface VII is a high-frequency strong absorption layer.

[0022] 2. The hollow nested design of 2-lossy dielectric hollow cylinder I, 10-lossy dielectric hollow cylinder II and 13-lossy dielectric hollow cylinder III can reduce the surface density of metamaterials while achieving ideal impedance matching effect, thus achieving the goal of lightweighting; in addition, the three-layer hollow nested design can enhance the mechanical properties of materials.

[0023] 3. The space capacitance formed by 4-electromagnetic metasurface II, 11-electromagnetic metasurface V and 14-electromagnetic metasurface VII can effectively adjust the overall impedance matching effect of metamaterials and optimize the absorption bandwidth and absorption intensity.

[0024] 4. Electromagnetic metasurfaces I, II, III, IV, V, VI, and VII are loaded onto a three-layer nested hollow column. Through spatial multiplexing of the electromagnetic wave oblique incidence direction, good impedance matching and energy absorption are achieved.

[0025] Technical effect

[0026] Compared with existing technologies, the spatially reusable strong-absorbing electromagnetic wave-absorbing metamaterial provided by this invention can achieve the following technical effects:

[0027] 1. The spatially reusable strong-absorbing electromagnetic wave-absorbing metamaterial provided by this invention achieves the effects of lightweight, low cost, and improved mechanical properties through a three-layer nested hollow column design.

[0028] 2. The spatially reusable strong-absorbing electromagnetic wave-absorbing metamaterial provided by this invention achieves ultra-wideband strong absorption performance, with a frequency band of at least 4.0-14.8 GHz where the reflection coefficient is below -30 dB when electromagnetic waves are incident perpendicularly, and a frequency band of at least 3.0-15.8 GHz where the reflection coefficient is below -20 dB.

[0029] 3. The spatially reusable strong-absorbing electromagnetic wave-absorbing metamaterial provided by this invention achieves ultra-wideband strong absorption performance, with a frequency band of at least 2.2-25.0 GHz where the reflection coefficient is less than -10 dB when electromagnetic waves are incident perpendicularly.

[0030] 4. The spatially reusable strong-absorbing electromagnetic wave-absorbing metamaterial provided by this invention has a large incident angle characteristic. The maximum oblique incident angle of the -30 dB absorption band can reach 30°, and it still maintains good absorption performance when the oblique incident angle reaches 75°. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of a spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial structural unit in an embodiment of the present invention;

[0032] Figure 2 This is a schematic diagram of the structural unit when the spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial hides the damaged medium hollow column I and its metasurface in an embodiment of the present invention;

[0033] Figure 3 This is a schematic diagram of the structural unit when the spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial hides the damaged medium hollow column I, the damaged medium hollow column II and its metasurface in an embodiment of the present invention;

[0034] Figure 4 This is a schematic diagram of a material plate with a 6×6 periodic arrangement of spatially reusable strong-absorbing electromagnetic wave-absorbing metamaterial in an embodiment of the present invention;

[0035] Figure 5 These are the reflection coefficient curves of the spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial in this embodiment of the invention under TE polarization at oblique incident angles of 0°, 15° and 30°.

[0036] Figure 6 These are the reflection coefficient curves of the spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial in this invention embodiment under TM polarization at oblique incident angles of 0°, 15°, and 30°.

[0037] Figure 7 These are the reflection coefficient curves of the spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial in this embodiment of the invention under TE polarization at oblique incident angles of 45°, 60°, 70° and 75°.

[0038] Figure 8 These are the reflection coefficient curves of the spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial in this invention embodiment under TM polarization at oblique incident angles of 45°, 60°, 70° and 75°;

[0039] Figure 9 This refers to the absorption rate of the spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial under TE polarization at different oblique incident angles in the embodiments of the present invention.

[0040] Figure 10 This refers to the absorption rate of the spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial under TM polarization at different oblique incident angles in the embodiments of the present invention.

[0041] In the diagram: 1. Skin; 2. Lossy dielectric hollow cylinder I; 3. Electromagnetic metasurface I; 4. Electromagnetic metasurface II; 5. Electromagnetic metasurface III; 6. Strong reflective backplate; 7. Rectangular resistive film I; 8. Rectangular resistive film II; 9. Electromagnetic metasurface IV; 10. 10-Lossy dielectric hollow cylinder II; 11. 11-Electromagnetic metasurface V; 12. Electromagnetic metasurface VI; 13. Lossy dielectric hollow cylinder III; 14. Electromagnetic metasurface VII; 15. Rectangular resistive film III. Detailed Implementation

[0042] To make the technical means, creative features, objectives and effects of this invention easier to understand, the following embodiments are described in detail with reference to the accompanying drawings.

[0043] This embodiment provides a space-reusable, strongly absorbing electromagnetic wave-absorbing metamaterial.

[0044] Figure 1 This is a schematic diagram of a spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial structural unit in an embodiment of the present invention;

[0045] Figure 2 This is a schematic diagram of the structural unit when the spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial hides the damaged medium hollow column I and its metasurface in an embodiment of the present invention;

[0046] Figure 3 This is a schematic diagram of the structural unit when a spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial hides a damaged medium hollow column I, a damaged medium hollow column II, and their metasurface in an embodiment of the present invention.

[0047] like Figures 1-3 As shown, in this embodiment, the spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial, in the XYZ three-dimensional coordinate system, includes, from top to bottom, 1-skin, a wave-absorbing functional layer, and 6-strong-reflective backplate in the Z direction; in the XOY plane, the wave-absorbing functional layer of the spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial includes, from outside to inside, 2-lossy dielectric hollow cylinder I, 10-lossy dielectric hollow cylinder II, and 13-lossy dielectric hollow cylinder III. In the Z direction, from top to bottom, 2-lossy dielectric hollow cylinder I is loaded with 3-electromagnetic metasurface I, 4-electromagnetic metasurface II, and 5-electromagnetic metasurface III; 10-lossy dielectric hollow cylinder II is loaded with 9-electromagnetic metasurface IV and 11-electromagnetic metasurface V; and 13-lossy dielectric hollow cylinder III is loaded with 12-electromagnetic metasurface VI and 14-electromagnetic metasurface VII.

[0048] Figure 4 This is a schematic diagram of a material plate with a 6×6 periodic arrangement of a spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial in an embodiment of the present invention.

[0049] like Figure 4 As shown, the spatially reusable strong-absorbing electromagnetic wave-absorbing metamaterial in this embodiment is periodically arranged in the XOY plane, with a period size of 10.0~30.0 mm. The size of the material is determined according to the actual needs of the application scenario.

[0050] In this embodiment, 1-skin, 2-lossy dielectric hollow cylinder I, 10-lossy dielectric hollow cylinder II, and 13-lossy dielectric hollow cylinder III are all materials with certain dielectric loss or magnetic loss characteristics, such as PLA, PET, Carbon / Glass Fiber Reinforced PLA, magnetic metal micropowder doped PPS, glass fiber board, aramid paper, etc., with a relative permittivity ranging from 1.5 to 15.0, a relative permeability ranging from 1.0 to 15.0, and a thickness of 0.1 to 5.0 mm; the heights of 2-lossy dielectric hollow cylinder I, 10-lossy dielectric hollow cylinder II, and 13-lossy dielectric hollow cylinder III are 10.0 to 35.0 mm.

[0051] In this embodiment, the 3-electromagnetic metasurface I is a rectangular ring resistive film disposed along the Z-axis on the inner or outer wall of the 2-lossy dielectric hollow cylinder I, attached to the 2-lossy dielectric hollow cylinder I, and connected end to end. The length and width of the rectangular ring are 10.0-30.0 mm and 2.0-10.0 mm, respectively, the linewidth of the rectangular ring is 0.5-4.5 mm, and the sheet resistance of the resistive film is 10-1000 Ω / sq.

[0052] In this embodiment, the 4-electromagnetic metasurface II is a ring structure disposed along the Z-axis on the upper half of the inner wall or outer wall of the 2-lossy dielectric hollow cylinder I, and is attached to the 2-lossy dielectric hollow cylinder I. The ring structure is composed of a low sheet resistance (0.1-30 Ω / sq) resistive film, the linewidth of the ring is 0.5-4.0 mm, and multiple high sheet resistance (30-1000 Ω / sq) rectangular resistive films 7 are uniformly distributed on it. The length and width of the resistive film 7 range from 0.5-5.0 mm.

[0053] In this embodiment, the 5-electromagnetic metasurface Ⅲ is a discontinuous low sheet resistance (0.1-30 Ω / sq) resistive film line disposed along the Z-axis on the inner or outer wall of the 2-lossy dielectric hollow cylinder Ⅰ, and attached to the 2-lossy dielectric hollow cylinder Ⅰ. The line width is 0.5-4.0 mm, and multiple high sheet resistance (30-1000 Ω / sq) rectangular resistive films 8 are uniformly distributed on it. The length and width of the resistive films 8 range from 0.5-5.0 mm.

[0054] In this embodiment, the 9-electromagnetic metasurface Ⅳ is disposed along the Z-axis on the inner wall or the upper half of the outer wall of the 10-lossy dielectric hollow cylinder Ⅱ, and is composed of multiple rectangular annular resistive films that surround the 10-lossy dielectric hollow cylinder Ⅱ. The impedance of the local area can be adjusted by connecting resistive film lines of different line widths. The sheet resistance of the resistive film is 30-1000 Ω / sq, and the line width is 0.5-4.0 mm.

[0055] In this embodiment, the 11-electromagnetic metasurface V is disposed along the Z-axis in the lower half of the inner or outer wall of the 10-lossy dielectric hollow cylinder II, and is composed of a complete resistive film that surrounds the 10-lossy dielectric hollow cylinder II. The sheet resistance of the resistive film is 30-1000 Ω / sq.

[0056] In this embodiment, 12-electromagnetic metasurface VI is disposed along the Z-axis and attached to the upper half of the inner or outer wall of 13-lossy dielectric hollow cylinder Ⅲ, and is composed of rectangular ring resistive films connected end to end. The length and width of the rectangular ring are 10.0-30.0 mm and 2.0-10.0 mm, respectively, the linewidth of the rectangular ring is 0.5-4.5 mm, and the sheet resistance of the resistive film is 10-1000Ω / sq.

[0057] In this embodiment, 14-electromagnetic metasurface VII is a ring structure disposed along the Z-axis on the lower half of the inner or outer wall of 13-lossy dielectric hollow cylinder III, attached to 13-lossy dielectric hollow cylinder III. The ring structure is composed of a low sheet resistance (0.1-30Ω / sq) resistive film, the linewidth of the ring is 0.5-4.0 mm, and multiple high sheet resistance (30-1000Ω / sq) rectangular resistive films 15 are uniformly distributed on it. The length and width of the resistive film 15 range from 0.5-5.0 mm.

[0058] Figure 5 These are the reflection coefficient curves of the spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial in this embodiment of the invention under TE polarization at oblique incident angles of 0°, 15°, and 30°.

[0059] like Figure 5 The figure shows the reflection coefficient curves under TE polarization at oblique incident angles of 0°, 15°, and 30°. When the incident angles are 0°, 15°, and 30°, the frequency bands with reflection coefficients below -30 dB are 4.0–14.8 GHz, 4.5–15.0 GHz, and 5.7–12.1 GHz, respectively; the frequency bands with reflection coefficients below -20 dB are 3.3–15.7 GHz, 3.1–15.8 GHz, and 2.2–15.4 GHz, respectively; and the frequency bands with reflection coefficients below -10 dB are 2.2–23.0 GHz, 3.9–19.5 GHz, and 2.4–18.0 GHz, respectively.

[0060] Figure 6 These are the reflection coefficient curves of the spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial in the embodiments of the present invention under TM polarization at oblique incident angles of 0°, 15° and 30°.

[0061] like Figure 6 The figure shows the reflection coefficient curves under TM polarization at oblique incident angles of 0°, 15°, and 30°. When the incident angles are 0°, 15°, and 30°: the frequency bands with reflection coefficients below -30 dB are 4.0–14.8 GHz, 4.1–14.6 GHz, and 4.6–14.6 GHz, respectively; the frequency bands with reflection coefficients below -20 dB are 3.2–15.8 GHz, 3.2–16.6 GHz, and 3.4–18.3 GHz, respectively; and the frequency bands with reflection coefficients below -10 dB are 2.2–23.0 GHz, 2.2–25.0 GHz, and 2.3–25.0 GHz, respectively.

[0062] Figure 7 These are the reflection coefficient curves of the spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial in this embodiment of the invention under TE polarization at oblique incident angles of 45°, 60°, 70° and 75°.

[0063] like Figure 7 The figure shows the reflection coefficient curves under TE polarization at oblique incident angles of 45°, 60°, 70°, and 75°. When the incident angle is 45°, the frequency bands with reflection coefficients below -20 dB and -10 dB are 5.7–17.1 GHz and 2.7–25.0 GHz, respectively; when the incident angle is 60°, the frequency bands with reflection coefficients below -20 dB and -10 dB are 8.0–22.8 GHz and 4.4–25.0 GHz, respectively; and when the incident angle is 75°, the frequency band with reflection coefficients below -10 dB is 9.8–25.0 GHz.

[0064] Figure 8 These are the reflection coefficient curves of the spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial in this embodiment of the invention under TM polarization at oblique incident angles of 45°, 60°, 70° and 75°.

[0065] like Figure 8The figure shows the reflection coefficient curves under TM polarization at oblique incident angles of 45°, 60°, 70°, and 75°. When the incident angle is 45°, the frequency bands with reflection coefficients below -20 dB and -10 dB are 3.7–25.0 GHz and 2.3–25.0 GHz, respectively; when the incident angle is 60°, the frequency bands with reflection coefficients below -20 dB and -10 dB are 5.5–25.0 GHz and 2.5–25.0 GHz, respectively; and when the incident angle is 75°, the frequency band with reflection coefficients below -10 dB is 6.0–25.0 GHz.

[0066] Figure 9 This refers to the absorption rate of the spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial under TE polarization at different oblique incident angles in the embodiments of the present invention.

[0067] like Figure 9 As shown, the absorption rate under TE polarization at different oblique incident angles is as follows. The metamaterial maintains an absorption rate greater than 70% in the 4.4–25.0 GHz frequency band within an incident angle of 75°.

[0068] Figure 10 This refers to the absorption rate of the spatially reused strong-absorbing electromagnetic wave-absorbing metamaterial under TM polarization at different oblique incident angles in the embodiments of the present invention.

[0069] like Figure 10 As shown, the absorptivity under TM polarization at different oblique incident angles is as follows. Within an incident angle of 75°, the metamaterial consistently exhibits an absorptivity greater than 70% in the 2.2–25.0 GHz frequency band and absorptivity greater than 70% in the 3.2–25.0 GHz frequency band.

[0070] Therefore, the spatially reusable strong-absorbing electromagnetic wave-absorbing metamaterial in this embodiment achieves broadband strong absorption performance through a multi-layered hollow cylindrical concentric nested structure and by loading different metasurface loss functional layers on the surface of each cuboid column. When electromagnetic waves are incident perpendicularly, the frequency band with a reflection coefficient below -30 dB is no less than 4.0-14.8 GHz; the frequency band with a reflection coefficient below -20 dB is no less than 3.0-15.8 GHz; it also exhibits large incident angle characteristics, with a maximum oblique incident angle of 30° in the -30 dB absorption band, and maintaining good absorption performance even at an oblique incident angle of 75°. This material has significant value in the current field of three-dimensional wave-absorbing metamaterials that are simple to manufacture, lightweight, and possess both ultra-wideband strong absorption and large-angle stability.

[0071] The above embodiments are preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention.

Claims

1. A space-reusable, high-absorption electromagnetic wave-absorbing metamaterial, characterized in that, In the XYZ three-dimensional coordinate system, from top to bottom in the Z direction, it includes a skin, a wave-absorbing functional layer, and a strong reflective backplate; the wave-absorbing functional layer in the XOY plane from outside to inside includes a lossy dielectric hollow column I, a lossy dielectric hollow column II, and a lossy dielectric hollow column III. The hollow cylinder I of the lossy medium is provided with electromagnetic metasurface I, electromagnetic metasurface II and electromagnetic metasurface III in sequence in the Z direction; The lossy medium hollow cylinder II is provided with electromagnetic metasurface IV and electromagnetic metasurface V in sequence in the Z direction; The damaged medium hollow cylinder III has an electromagnetic metasurface VI and an electromagnetic metasurface VII arranged sequentially in the Z direction.

2. The space-reusable, high-absorption electromagnetic wave-absorbing metamaterial according to claim 1, characterized in that: The microwave absorbing metamaterial is periodically arranged in the XOY plane with a period of 10.0-30.0 mm.

3. The space-reusable, high-absorption electromagnetic wave-absorbing metamaterial according to claim 1, characterized in that: The relative permittivity of the skin, the lossy dielectric hollow cylinder I, the lossy dielectric hollow cylinder II, and the lossy dielectric hollow cylinder III is 1.5-15.0, the relative permeability is 1.0-15.0, and the thickness is 0.1-5.0 mm. The heights of the three hollow cylinders of the damaged medium (I, II, and III) are all 10.0-35.0 mm.

4. The space-reusable, high-absorption electromagnetic wave-absorbing metamaterial according to claim 1, characterized in that: The electromagnetic metasurface I is an annular resistive film attached to the inner or outer wall of the hollow cylinder I of the lossy medium, arranged along the Z-axis. The annular resistive film has a length of 10.0-30.0 mm, a width of 2.0-10.0 mm, a linewidth of 0.5-4.5 mm, and a sheet resistance of 10-1000 Ω / sq.

5. The space-reusable, high-absorption electromagnetic wave-absorbing metamaterial according to claim 1, characterized in that: The electromagnetic metasurface II is a ring structure attached to the inner or outer wall of the lossy dielectric hollow cylinder I, arranged along the Z-axis. The linewidth of the ring structure is 0.5-4.0 mm, and the sheet resistance is 0.1-30 Ω / sq. Multiple rectangular resistive films I are uniformly distributed on the ring structure. The length and width of the rectangular resistive films I are both 0.5-5.0 mm, and the sheet resistance is 30-1000 Ω / sq.

6. The space-reusable, high-absorption electromagnetic wave-absorbing metamaterial according to claim 1, characterized in that: The electromagnetic metasurface III is a discontinuous resistive film line attached to the inner or outer wall of the hollow cylinder I of the lossy medium, arranged along the Z-axis. The linewidth of the resistive film line is 0.5-4.0 mm, and the sheet resistance is 0.1-30 Ω / sq. Multiple rectangular resistive films II are uniformly distributed on the resistive film line. The length and width of the rectangular resistive films II are both 0.5-5.0 mm, and the sheet resistance is 30-1000 Ω / sq.

7. The space-reusable, high-absorption electromagnetic wave-absorbing metamaterial according to claim 1, characterized in that: The electromagnetic metasurface IV consists of multiple annular resistive films attached to the inner wall or the upper half of the outer wall of the hollow cylinder II of the lossy medium, arranged along the Z-axis. The annular resistive films achieve local impedance adjustment by connecting resistive film lines of different linewidths. The linewidth of the annular resistive films is 0.5-4.0 mm, and the sheet resistance is 30-1000 Ω / sq.

8. The space-reusable, high-absorption electromagnetic wave-absorbing metamaterial according to claim 1, characterized in that: The electromagnetic metasurface V is a complete resistive film attached to the lower half of the inner or outer wall of the hollow cylinder II of the lossy medium, and is arranged along the Z-axis direction. The sheet resistance of the complete resistive film is 30-1000 Ω / sq.

9. The space-reusable, high-absorption electromagnetic wave-absorbing metamaterial according to claim 1, characterized in that: The electromagnetic metasurface VI is an annular resistive film attached to the upper half of the inner or outer wall of the hollow cylinder III of the lossy medium, arranged along the Z-axis. The annular resistive film has a length of 10.0-30.0 mm, a width of 2.0-10.0 mm, a linewidth of 0.5-4.5 mm, and a sheet resistance of 10-1000 Ω / sq.

10. The space-reusable, high-absorption electromagnetic wave-absorbing metamaterial according to claim 1, characterized in that: The electromagnetic metasurface VII is a ring structure attached to the lower half of the inner or outer wall of the lossy dielectric hollow cylinder III, arranged along the Z-axis. The linewidth of the ring structure is 0.5-4.0 mm, and the sheet resistance is 0.1-30 Ω / sq. Multiple rectangular resistive films III are uniformly distributed on the ring structure. The length and width of the rectangular resistive films III are both 0.5-5.0 mm, and the sheet resistance is 30-1000 Ω / sq.

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