An electromagnetic wave absorbing metamaterial

Abstract

The present invention provides a wave-absorbing metamaterial, which comprises a dielectric substrate and artificial microstructures periodically arrayed on the dielectric substrate. The artificial microstructures are made of an electrically lossy material. The artificial microstructures include a first structure, a second structure and a third structure which are arranged at intervals. The second structure is arranged within the first structure, and the third structure is arranged within the second structure. The first structure is a square ring, and both the second structure and the third structure are symmetric structures and have a common symmetry center with the first structure. Through reasonable design of the artificial microstructures in the metamaterial, the present invention obtains a wave-absorbing metamaterial that is lightweight, wideband, wide-angle and has a high wave-absorbing effect, covering the X-band to the Ka-band.

Description

Technical Field

[0001] The present invention relates to the field of microwave absorbing metamaterials, and particularly to a polarization-independent, broadband, wide-angle, and highly absorbing microwave absorbing metamaterial.

Background Art

[0002] With the continuous development of modern electromagnetic technologies, the division of the electromagnetic spectrum has become increasingly detailed, and the boundaries have become less clear. At the same time, the development of electromagnetic technologies has also given rise to the problem of electromagnetic pollution that threatens human survival. Broadband electromagnetic absorbing materials are the key to solving this problem and can effectively control electromagnetic pollution, while traditional absorbing materials are difficult to achieve broadband absorption.

[0003] Metamaterials are a new type of artificial synthetic material, which are composed of a dielectric substrate made of non-metallic materials and multiple artificial microstructures periodically arrayed on the dielectric substrate. The artificial microstructures are attached to the surface of the dielectric substrate or embedded inside the substrate. As a new member of the family of absorbing materials, microwave absorbing metamaterials have the characteristics of thin thickness, wide absorption bandwidth, and perfect absorption in any frequency band, and have extensive applications in the field of wave absorption. However, existing microwave absorbing metamaterials still cannot achieve broadband and high absorption effects covering from the X-band to the Ka-band. Therefore, researching metamaterial absorbing structures with wide absorption bandwidth, good absorption effect, and light weight has great potential value.

Summary of the Invention

[0004] To solve the above technical problems, the present invention provides a microwave absorbing metamaterial, which includes a dielectric substrate and artificial microstructures periodically arrayed on the dielectric substrate. The artificial microstructures are made of an electrically lossy material. The artificial microstructures include a first structure, a second structure, and a third structure arranged at intervals. The second structure is disposed inside the first structure, and the third structure is disposed inside the second structure. The first structure is a square ring, and the second structure and the third structure are both symmetric structures and have a common symmetry center with the first structure.

[0005] In some embodiments of the present invention, the second structure is a square structure or a rhombus structure, and a regular polygon opening is provided at the center of the second structure. The third structure is disposed inside the regular polygon opening.

[0006] In some embodiments of the present invention, the third structure is a regular polygon or a circular structure.

[0007] In some embodiments of the present invention, the second structure is a rhombus structure, a square opening is provided at the center of the rhombus structure, and the third structure is a circular structure.

[0008] In some embodiments of the present invention, the unit period of the artificial microstructures is P = 7 - 9 mm.

[0009] In some embodiments of the present invention, the outer side length a of the square ring is 6.5 - 7 mm, and the inner side length ra is 2.6 - 3.4 mm.

[0010] In some embodiments of the present invention, the side length b of the rhombus structure is 1.5 - 2.2 mm.

[0011] In some embodiments of the present invention, the regular polygon opening is a square, and the side length rb of the square opening is 0.8 - 1.1 mm.

[0012] In some embodiments of the present invention, the third structure is a circular structure, and the diameter D of the circular structure is 0.2 - 0.4 mm.

[0013] In some embodiments of the present invention, the unit period of the artificial microstructure is P = 8 mm, the outer side length a of the square ring is 6.8 mm, the inner side length ra is 3.2 mm, the side length b of the rhombus structure is 2 mm, the side length rb of the square opening is 1 mm, and the diameter D of the circular structure is 0.3 mm.

[0014] The present invention provides a microwave absorbing metamaterial, which includes a dielectric substrate and artificial microstructures periodically arrayed on the dielectric substrate. The artificial microstructures are made of an electrically lossy material and include a first structure, a second structure, and a third structure arranged at intervals. The second structure is disposed within the first structure, and the third structure is disposed within the second structure. The first structure is a square ring, and the second structure and the third structure are both symmetric structures and have a common symmetry center with the first structure. Through the optimized design of the artificial microstructures in the microwave absorbing metamaterial, the present invention obtains a microwave absorbing metamaterial that is lightweight, broadband, wide-angle, and has a high microwave absorption effect, covering the X - band to the Ka - band.

Description of the Drawings

[0015] Figure 1 Schematic diagram of a unit structure of an artificial microstructure in a microwave absorbing metamaterial of the present invention;

[0016] Figure 2 Side view of a microwave absorbing metamaterial of the present invention;

[0017] Figure 3 TE polarization wave spectrum of a microwave absorbing metamaterial of the present invention;

[0018] Figure 4 Figure 3 TM polarization wave spectrum of the microwave absorbing metamaterial.

Detailed Embodiments

[0019] In order to make the objectives, technical solutions and advantages of the present invention more clear and understandable, the present invention will be further described in detail below in conjunction with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0020] Please refer to Figure 1 , the present invention provides a microwave absorbing metamaterial, which includes a dielectric substrate and artificial microstructures periodically arranged on the dielectric substrate. The artificial microstructures are made of an electrically lossy material. The artificial microstructures include a first structure 100, a second structure 200, and a third structure 300 that are spaced apart. The second structure 200 is disposed within the first structure, and the third structure 300 is disposed within the second structure. The first structure 100 is a square ring, and the second structure 200 and the third structure 300 are both symmetric structures and have a common symmetry center with the first structure. In this embodiment, the second structure 200 is a rhombus structure, and a square opening is provided at the center of the rhombus structure. The third structure 300 is a circular structure.

[0021] In some embodiments of the present invention, the resistance value of the electrically lossy material is 10 - 1000 Ω / □.

[0022] In some embodiments of the present invention, the artificial microstructures are made of a lossy metal material, and the resistance value of the lossy metal material is 10 - 50 Ω.

[0023] In some other embodiments of the present invention, the second structure 200 may also be a square structure.

[0024] In some other embodiments of the present invention, the third structure 300 may also be a regular polygon structure.

[0025] In some other embodiments of the present invention, a regular n-sided polygon opening is provided at the center of the second structure 200, which may specifically be a regular pentagon opening, or a regular hexagon opening, or a regular octagon opening, etc. The third structure 300 is disposed within the regular n-sided polygon opening.

[0026] In some embodiments of the present invention, the unit period of the artificial microstructures is P = 7 - 9 mm.

[0027] In some embodiments of the present invention, the outer side length a of the square ring is 6.5 - 7 mm, and the inner side length ra is 2.6 - 3.4 mm.

[0028] In some embodiments of the present invention, the side length b of the rhombus structure is 1.5 - 2.2 mm.

[0029] In some embodiments of the present invention, the side length rb of the square opening is 0.8 - 1.1 mm.

[0030] In some embodiments of the present invention, the diameter D of the circular structure is 0.2-0.4 mm.

[0031] To further illustrate the performance of the absorbing metamaterial of the present invention, it is further defined below. In this embodiment, the second structure 200 is a prismatic structure with a square opening at the center. The third structure 300 is a circular structure. The unit period of the artificial microstructure is P=8mm, the outer side length of the square ring is a=6.8mm, the inner side length ra=3.2mm, the side length of the prismatic structure is b=2mm, the side length of the square opening is rb=1mm, and the diameter of the circular structure is D=0.3mm. The artificial microstructure is made of lossy metal material, and the resistance value of the lossy metal material is Rs=40Ω. The entire metamaterial structure layer is sandwiched between two layers of medium with a thickness of d1=d2=2mm, and its structure is as follows: Figure 2 As shown in the figure, the dielectric constant of the upper dielectric layer is 2.94 and the loss tangent is 0.0025; the dielectric constant of the lower dielectric layer is 1.08, and the back of the lower dielectric layer is covered with a metal bottom plate. The electromagnetic performance of the above metamaterial is simulated and tested, and the results are shown in the figure. Figure 3 and Figure 4 As shown. Figure 3 and Figure 4 It can be seen that when the electromagnetic wave is incident vertically, the metamaterial achieves an absorption performance of more than 90% in the range of 7.5 to 32 GHz, and has the characteristics of being polarization-independent; in addition, regardless of TE polarization or TM polarization, the metamaterial can achieve very good and efficient absorption performance in a large angular range of 0 to 40 degrees, and has the effect of broadband large angular absorption.

[0032] In the above embodiments, the present invention is only exemplarily described, but those skilled in the art may make various modifications to the present invention without departing from the spirit and scope of the present invention after reading this patent application.

Claims

1. An electromagnetic wave absorbing metamaterial, characterized in that, The absorbing metamaterial includes a dielectric substrate and artificial microstructures periodically arrayed on the dielectric substrate. The artificial microstructures are made of an electrically lossy material. The artificial microstructures include a first structure, a second structure, and a third structure which are spaced apart. The second structure is disposed within the first structure, and the third structure is disposed within the second structure. The first structure is a square loop, and the second structure and the third structure are both symmetric structures and have a common center of symmetry with the first structure; Wherein, the second structure is a rhombus structure, and a regular polygon opening is provided at the center of the second structure. The third structure is disposed within the regular polygon opening; the third structure is a solid structure.

2. The microwave absorbing metamaterial according to claim 1, characterized in that, The third structure is a regular polygon or a circular structure.

3. The microwave absorbing metamaterial according to claim 2, wherein A square opening is provided at the center of the rhombus structure. The third structure is disposed within the square opening, and the third structure is a circular structure.

4. The microwave absorbing metamaterial according to claim 3, wherein The unit period of the artificial microstructures is P = 7 - 9 mm.

5. The microwave absorbing metamaterial according to claim 4, characterized in that, The outer side length a of the square loop is 6.5 - 7 mm, and the inner side length ra is 2.6 - 3.4 mm.

6. The microwave absorbing metamaterial according to claim 5, wherein, The side length b of the rhombus structure is 1.5 - 2.2 mm.

7. The wave-absorbing metamaterial according to claim 6, characterized in that, The opening is a square, and the side length rb of the opening is 0.8 - 1.1 mm.

8. The microwave absorbing metamaterial according to claim 7, wherein The third structure is a circular structure, and the diameter D of the circular structure is 0.2 - 0.4 mm.

9. The microwave absorbing metamaterial according to claim 3, wherein The unit period of the artificial microstructures is P = 8 mm, the outer side length a of the square loop is 6.8 mm, the inner side length ra is 3.2 mm, the side length b of the rhombus structure is 2 mm, the side length rb of the square opening is 1 mm, and the diameter D of the circular structure is 0.3 mm.

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