Hinge deformation adjustable metamaterial wave-absorbing unit of composite magnetic patch and regulation and control method

Abstract

The invention discloses a hinge deformation adjustable metamaterial wave-absorbing unit of a composite magnetic patch and a regulation and control method. The wave absorbing unit is formed by connecting a dielectric loss framework and a magnetic material patch through a hinge structure; according to the hinge structure, the clamping hole and the inserting piece which are in special geometric fit are adopted, and stable and continuous rotation from 0 degree to 90 degrees is achieved; by adjusting the rotation angle t, the unit period, thickness and density can be synchronously and continuously changed, so that dynamic and continuous tuning of the electromagnetic wave absorption performance is realized; in order to realize large-scale application, the middle section of the framework is provided with a clamping hole structure, and array expansion of units can be realized through double-end splicing plug-ins. By utilizing a dielectric / magnetic composite loss mechanism, high-efficiency, continuous and adjustable electromagnetic wave absorption performance can be provided within an extremely wide band of 1.2 GHz to 40.0 GHz, and the technical problems that an existing wave absorption structure is low in tuning freedom degree and inconvenient in array expansion are solved.

Description

Technical Field

[0001] This invention belongs to the field of electromagnetic functional materials technology, specifically relating to a hinged deformation adjustable metamaterial wave-absorbing unit and control method of a composite magnetic patch. Background Technology

[0002] In recent years, electromagnetic metamaterials have attracted widespread attention in fields such as stealth, electromagnetic compatibility, and sensors due to their unique ability to control electromagnetic wave parameters. Metamaterial absorbers (MAs) achieve efficient absorption of incident electromagnetic waves through ingenious structural design. However, once traditional absorbing structures are fabricated, their operating frequency and performance remain fixed, making it difficult to adapt to complex and variable electromagnetic environments. To address this issue, researchers have proposed various tuning mechanisms, mainly divided into two major technical routes: electronic tuning and mechanical tuning.

[0003] Electrically controlled tuning technology integrates electronic components such as diodes, relying on external electrical signals or changes in incident power to achieve rapid switching of absorption performance. Chinese patent CN116365254A discloses a reconfigurable power-dependent absorbing metasurface for surface waves. This metasurface achieves excellent power tuning performance: as the incident power changes from 5 dBm to 20 dBm, its absorption rate adjustment range gradually increases from 19.4% to 92.7%, achieving 30%–80% absorption rate adjustment within the 4.93 GHz–5.56 GHz frequency band (relative bandwidth 12.0%). Despite achieving rapid control, the biggest problem with this type of electrically controlled active structure is its high cost and high energy consumption. It must rely on complex external power supply networks and control circuits, and requires an external power supply or a specific power incident wave drive, making it unsuitable for applications requiring structural simplicity or passive environments. Furthermore, its operating frequency band is often narrow, and its absorption performance is limited by the electrical characteristics of the components. Mechanical tuning technology requires no external power supply and achieves control by changing the structure's geometry, making it an ideal passive and adjustable solution. However, existing structures still have shortcomings in tuning continuity and structural stability. Chinese patent CN120879232A discloses an adjustable paper-cutting and folding electromagnetic absorption structure. This structure achieves a -10 dB broadband absorption band in three discrete states by changing the coordinated motion of the fractal paper-cutting and folding structure. The operating frequency band of steady state one is 3.1 GHz - 13.1 GHz; the operating frequency band of steady state two is 5.5 GHz - 14.5 GHz; and the operating frequency bands of the self-locking state are 5.3 GHz - 8.8 GHz and 11.9 GHz - 13.9 GHz, with an absorption peak of -31.6 dB. Although this structure achieves excellent broadband and deep absorption performance, its control mechanism relies on discrete steady-state switching, making it difficult to achieve continuous and precise tuning of absorption performance. Furthermore, the complex paper-cutting and folding structure is prone to structural fatigue during repeated movements, and the stability of the connecting parts is poor. Therefore, it is necessary to design a stable and reliable absorbing structure to solve the problems of tuning continuity, manufacturing cost, and broadband high-efficiency absorption. Summary of the Invention

[0004] The purpose of this invention is to provide a hinged deformation-tunable metamaterial absorbing unit of composite magnetic patch and its control method. This unit can not only achieve continuous tuning, but also has the ability to array splicing and flexible expansion, so as to solve the above-mentioned problems in tuning continuity, array expansion and performance.

[0005] The technical solution to achieve the purpose of this invention is as follows: a hinged, deformable, adjustable metamaterial absorbing unit with composite magnetic patches. This unit is periodically arranged in the transverse and longitudinal directions. The absorbing unit is formed by connecting a dielectric loss frame and a magnetic material patch through hinged parts, and is connected to a reflective backplate to achieve a combined effect of dielectric loss and magnetic loss. The dielectric loss frame has locking holes at both ends, and the hinged parts have insert structures that cooperate with the locking holes. After the insert structures on the hinged parts are inserted into the locking holes at the ends of the dielectric loss frame, they can rotate continuously and freely within a range of 0° to 90°. By changing the rotation angle, the periodicity, thickness, and density of the unit can be adjusted, thereby dynamically and continuously tuning the electromagnetic wave absorption performance. The middle section of the other side of the dielectric loss frame has locking holes consistent with those at both ends, used to splice adjacent units.

[0006] Furthermore, the card hole structure includes a shallow square hole with a side length of m and a deep hole with a diameter of m. The circular hole; the plug-in structure includes a cylinder with a diameter of m and a cube with a cross-sectional side length of m; the diagonal length of the cross-section of the cube is... The diameter is equal to that of the circular hole to ensure continuous and free rotation of the hinge structure within the range of 0° to 90°.

[0007] Furthermore, the unit array is expanded through a dual-head splicing plug; the splicing plug is designed with plug structures at both ends, each end including a cylinder with a diameter of m and a cube with a cross-sectional side length of m, and the splicing plug connects the middle section card hole structure on two adjacent unit skeletons.

[0008] Furthermore, during rotation, the four corners of the plug-in structure block are continuously constrained by the edges of the shallow square holes of the card hole structure to achieve the stability and anti-detachment of the structural connection.

[0009] Furthermore, the dielectric loss skeleton and the hinge component are fabricated by 3D printing from carbon black mixed polylactic acid filaments with dielectric loss properties.

[0010] Furthermore, the magnetic material patch is made of carbonyl iron powder mixed with resin and is attached to the sidewall of the dielectric loss skeleton.

[0011] Furthermore, the rotation angle can be continuously varied from 0° to 90°. By continuously adjusting the rotation angle t, the absorbing unit can achieve a high reflection coefficient within an extremely wide frequency band from 1.2 GHz to 40.0 GHz. The unit exhibits broadband absorption of less than -10 dB, and by continuously adjusting t, it can continuously achieve three independent frequency bands within the range of 7.54 GHz to 12.48 GHz, 15.34 GHz to 25.01 GHz, and 26.58 GHz to 40.00 GHz. The absorption band is less than -20 dB.

[0012] This invention also provides a method for dynamically controlling the electromagnetic wave absorption performance, employing the aforementioned metamaterial absorbing unit. The method includes: adjusting the rotation angle t on the hinged structure of the metamaterial absorbing unit, wherein the rotation angle t continuously varies within the range of 0° to 90°; the continuous change in the rotation angle t synchronously causes continuous changes in the period, thickness, and density of the absorbing unit, thereby achieving continuous control of the equivalent input impedance of the metamaterial; and realizing continuous broadband absorption control of the unit within an extremely wide frequency band from 1.2 GHz to 40.0 GHz.

[0013] Compared with the prior art, the present invention has the following advantages: (1) High degree of freedom dynamic tuning: By adopting a special hinge structure, continuous control of rotation from 0° to 90° is achieved, overcoming the defect that can only achieve discrete tuning, and significantly improving the degree of tuning freedom. (2) Ultra-wideband absorption: By utilizing the optimized design of the composite magnetic patch and combining it with the dielectric loss structure, magnetic loss is effectively introduced, greatly enhancing the loss capability of the structure, and realizing ultra-wideband absorption (1.4 GHz - 40 GHz). Highly efficient absorption. (3) Multi-band highly efficient absorption: modulation results (such as...) Figure 4 The heat map shown demonstrates that, through continuous tuning, the unit can achieve three independent frequency bands within the range of 7.54 GHz to 12.48 GHz, 15.34 GHz to 25.01 GHz, and 26.58 GHz to 40.00 GHz. Deep absorption frequency band. (4) Strong array expansion capability: The introduction of mid-section card hole and dual-head plug-in design enables the absorption unit array to be easily and quickly spliced ​​and flexibly expanded in the horizontal and vertical directions. Attached Figure Description

[0014] The accompanying drawings constitute a part of this invention and are used to explain embodiments of the invention.

[0015] Figure 1The following are detailed diagrams of the hinge structure of the composite magnetic patch, used to illustrate the connection and fit of the hinge joint: (a) is an exploded isometric view showing the three-dimensional form of the plug-in structure 201 and the snap-hole structure 202 before assembly; (b) is a sectional view showing the relative positions of the cylinder 203, block 204, square hole 205, and round hole 206 of each feature structure of the plug-in structure 201 and the snap-hole end 202.

[0016] Figure 2 This is a schematic diagram of a hinged deformable metamaterial absorbing unit with a composite magnetic patch. The unit consists of a dielectric loss frame 101, a hinge component 102, a magnetic material patch 104, and a metal reflective backplate 105 at the bottom; the rotation angle is shown. The tuning mechanism rotates from 0° to 45° and then to 90°.

[0017] Figure 3 This is a schematic diagram of the array splicing structure, showing how adjacent units are spliced ​​at the slot 202 in the middle section of the dielectric skeleton 101 via a double-headed plug 103, which is used to achieve array expansion.

[0018] Figure 4 The CST simulation results show the reflection coefficient ( ) under continuous tuning from 0° to 90°. Heat map as a function of frequency and rotation angle t.

[0019] Figure 5 The CST simulation results are shown in the figure, illustrating different rotation angles under optimal structural parameters. The reflection coefficient curve below ( ). Detailed Implementation

[0020] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0021] Combination Figure 1 , Figure 2This invention provides a metamaterial microwave absorbing unit with adjustable hinge deformation and composite magnetic patch. The metamaterial microwave absorbing unit consists of a dielectric loss skeleton 101, a magnetic material patch 104, a hinge component 102, and a bottom metal reflective backplate 105. The dielectric loss skeleton 101 and the hinge component 102 are integrally formed using carbon black (CB) mixed with polylactic acid (PLA) filaments with dielectric loss characteristics through high-precision 3D printing technology. The skeleton thickness is preferably 4 mm. The magnetic material patch 104 is a composite material with high magnetic loss characteristics, made by mixing carbonyl iron powder and polymer resin at high temperature, then cooling, curing, and pressing. The patch is attached to the sidewall of the dielectric loss skeleton 101 to achieve dielectric / magnetic dual-loss composite. The reflective backplate 105 is made of a high conductivity material (such as aluminum), and its thickness is much greater than the skin depth of electromagnetic waves to achieve total reflection of electromagnetic waves, reducing transmission loss to zero.

[0022] The hinge structure consists of locking structures 202 at both ends of the dielectric skeleton 101 and insert structures 201 on the independently fabricated hinge part 102. The locking structure 202 includes a square hole 205 with a side length of m and a diameter of... The circular hole 206 is used. The plug-in structure 201 includes a cylinder 203 with a diameter of m and a cube 204 with a cross-sectional side length of m. The diagonal length of the cube 204 is exactly equal to the diameter of the circular hole 206, ensuring that the plug-in structure 201 can rotate freely from 0° to 90° within the locking structure 202. Friction exists between the two, ensuring that the hinge structure can be fixed at the required rotation angle. During rotation, the four corners of the cube 204 are constrained by the edges of the shallow square hole 205, effectively preventing the plug-in structure 201 from axially disengaging, and ensuring the stability and reliability of the structure during dynamic tuning.

[0023] The unit achieves rotatable deformation through a hinged structure. An externally applied driving force (e.g., a push rod or motor) adjusts the rotation angle. Available to Continuous variation within a range. The change simultaneously triggered changes in period, thickness, and structural density, realizing the equivalent input impedance of the metamaterial. The dynamic and continuous tuning allows it to be continuously matched with the free space impedance, thereby achieving a wide range of electromagnetic resonant frequency tuning and absorption performance control.

[0024] Array splicing and expansion, such as Figure 3As shown, the dielectric loss frame 101 has a locking structure 202 in the middle section, consistent with the two ends. The splicing element adopts a double-ended plug 103, with both ends being plug structures 201, namely composed of a cylinder 203 with a diameter of m and a cube 204 with a cross-sectional side length of m. The two ends of the double-ended plug 103 are respectively inserted into the locking structures 202 in the middle section of two adjacent absorbing unit frames. Utilizing the stability characteristics of the hinge structure, a rigid and rotatable connection between adjacent units is achieved. This design allows individual absorbing units to be easily and quickly spliced ​​laterally and longitudinally into a large-scale metamaterial absorbing array, greatly simplifying system integration and deployment.

[0025] Optimal structural parameters: Through electromagnetic simulation optimization (CST Studio Suite), the preferred structural parameters were determined as follows: dielectric skeleton thickness 4 mm; magnetic material patch thickness a = 1.5 mm; patch length l = 14.2 mm; patch width w = 3.5 mm. Figure 4 The thermal diagram shows the reflection coefficient S during continuous tuning from 0° to 90°. 11 The variation with frequency (0.5 GHz - 40 GHz). The thermogram clearly shows that by continuously adjusting the t-value, multiple independent deep absorption bands can be flexibly achieved continuously within an extremely wide bandwidth of 1.2 GHz - 40 GHz. The absorption efficiency is extremely high. Throughout the entire tuning range, the light-colored region covers a large area of ​​the frequency space, demonstrating the structure's stability. Ultra-wideband continuous absorption and control capability. Figure 5The CST simulation results specifically illustrate the tuning of absorption performance with different rotation angles t: At t = 0°, the unit is fully deployed, achieving -10 dB absorption in the 10.3 GHz – 15.4 GHz frequency band, with a total structure thickness of only 7 mm, facilitating overall storage; at t = 30°, the designed structure achieves broadband absorption of -10 dB in the 4.9 GHz – 36.2 GHz frequency band, and efficient absorption of -20 dB in the X-band of 8.9 GHz – 11.3 GHz; as the rotation angle t gradually increases, the absorption peak of the designed structure gradually shifts to higher frequencies. When t = 60°, it achieves ultra-wideband absorption of -10 dB in the frequency band from 1.5 GHz to above 40 GHz, with a relative bandwidth exceeding 185.5%, while also achieving absorption in the 15.9 GHz – 22.0 GHz, 27.8 GHz – 31.8 GHz, and 32.5 GHz – 10 GHz frequencies. High-efficiency absorption of -20 dB was achieved in the high-frequency range of 36.7 GHz. When t = 90°, the rotation angle t reaches its design maximum value, at which point the structure is completely folded, weakening the absorption capability. This allows for ultra-wideband absorption of -10 dB in the frequency band from 13.0 GHz to above 40 GHz, and high-efficiency absorption of -20 dB in the frequency bands of 17.8 GHz - 20.7 GHz and 31.1 GHz - 32.5 GHz. This demonstrates that specific absorption targets can be flexibly achieved by adjusting the t value of the designed structure.

[0026] The metamaterial absorbing unit and its control method proposed in this invention are structurally stable, easy to prepare, and have flexible array expansion capabilities. Furthermore, they achieve continuous and efficient control of electromagnetic wave absorption performance over an extremely wide frequency band, and have significant industrial application value.

[0027] The above description is merely a preferred embodiment of the present invention and should not be construed as limiting the scope of the invention. Any simple equivalent transformations and modifications made based on the claims and description of the present invention should be considered within the scope of protection of this patent. Therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A metamaterial absorber unit of a hinged metamaterial patch composite, the unit being periodically arranged in a transverse and longitudinal direction, characterized in that: The absorbing unit is connected by a hinge part (102) with a dielectric loss skeleton (101) and a magnetic material patch (104), and is connected with a reflective back plate (105), to realize the combined effect of dielectric loss and magnetic loss; the dielectric loss skeleton (101) is provided with a clamping hole structure (202) at both ends, and the hinge part (102) is provided with a plug-in structure (201) matched with the clamping hole structure (202); after the plug-in structure (201) on the hinge part (102) is inserted into the end side clamping hole structure (202) of the dielectric loss skeleton (101), continuous and free rotation within 0° to 90° is realized, and by changing the rotation angle, period change, thickness adjustment and unit density change of the unit are realized, so that the electromagnetic wave absorbing performance is dynamically and continuously tuned; the middle section of the other side of the dielectric loss skeleton (101) is provided with a clamping hole structure (202) consistent with both ends, for realizing splicing of adjacent units.

2. The hinged metamaterial absorber unit of claim 1, wherein: The card hole structure (202) includes shallow square holes (205) with side length m and deep circular holes (206) with diameter The insert structure (201) includes cylinders (203) with diameter m and square blocks (204) with cross-sectional side length m; the cross-sectional diagonal length of the square blocks (204) is equal to the diameter of the circular holes (206) to ensure continuous and free rotation of the hinge structure within the range of 0° to 90°.

3. The hinged metamaterial absorber unit of claim 1 or 2, wherein: The unit array is expanded by a double-head splicing plug-in (103); the splicing plug-in (103) is designed as a plug-in structure (201) at both ends, each end including a cylinder with a diameter of m and a square block with a cross-sectional side length of m, and the splicing plug-in (103) connects the middle clamping hole structure (202) on the skeletons of adjacent two units.

4. The hinged metamaterial absorber unit of claim 2, wherein: The four corners of the plug-in structure square block (204) are continuously constrained by the edges of the shallow square holes (205) of the clamping hole structure (202) during rotation, to realize stability and anti-falling of the structure connection.

5. The hinged metamaterial absorber unit of claim 1, wherein: The dielectric loss skeleton (101) and the hinge part (102) are prepared by 3D printing of carbon black mixed polylactic acid filaments with dielectric loss characteristics.

6. The hinged metamaterial absorber unit of claim 5, wherein: The magnetic material patch (104) is prepared by mixing carbonyl iron powder with resin, and is attached to the side wall of the dielectric loss skeleton (101).

7. The hinged metamaterial absorber unit of claim 1, wherein: The continuous change range of the rotation angle is 0° to 90°, and by continuously adjusting the rotation angle t, the absorption unit can realize the reflection coefficient in an extremely wide frequency band of 1.2 GHz to 40.0 GHz A wide-band absorption less than -10 dB, and the unit can continuously realize three independent frequency bands of 7.54 GHz to 12.48 GHz, 15.34 GHz to 25.01 GHz and 26.58 GHz to 40.00 GHz in the range of 7.54 GHz to 40.00 GHz by continuously adjusting t A deep absorption frequency band less than -20 dB.

8. A method of dynamically tuning electromagnetic wave absorption performance, characterized by, The method comprises adjusting the rotation angle t on the hinge structure of the metamaterial absorbing unit, the rotation angle t continuously changes within 0° to 90°; the continuous change of the rotation angle t synchronously causes continuous changes of the period, thickness and density of the absorbing unit, so as to realize continuous regulation of the equivalent input impedance of the metamaterial; and the unit realizes continuous broadband absorption regulation within an extremely wide frequency band of 1.2 GHz to 40.0 GHz.

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