Electromagnetic shielding structure

Abstract

The utility model provides an electromagnetic shielding structure, and relates to the technical field of wireless. The electromagnetic shielding structure comprises a first metasurface layer; the wave-transparent layer is arranged on one side of the first metasurface layer; the second metasurface layer is arranged on one side, deviating from the first metasurface layer, of the wave-transparent layer; the control unit is respectively connected with the first metasurface layer and the second metasurface layer; wherein the control unit sends a working frequency control signal to the first metasurface layer, and / or sends a shielding efficiency control signal to the second metasurface layer. According to the scheme of the utility model, the problem that the frequency and the shielding efficiency are difficult to adjust in the existing electromagnetic shielding technology is solved.

Description

Technical Field

[0001] The utility model relates to the field of wireless technology, in particular to an electromagnetic shielding structure. Background Art

[0002] With the popularization of electronic devices and the development of wireless communication technology, the sources of electromagnetic radiation that people are exposed to in their daily lives are increasing. For example, televisions, mobile phones, microwave ovens, computers, communication base stations, radar systems, etc. are all sources of electromagnetic radiation.

[0003] Currently, electromagnetic radiation can be blocked or reduced through electromagnetic shielding technology. However, traditional electromagnetic shielding technology can generally only shield electromagnetic radiation in a specific frequency band, and it is difficult to achieve electromagnetic shielding with adjustable frequency and shielding efficiency. Utility Model Content

[0004] The utility model aims to provide an electromagnetic shielding structure, which solves the problem that the existing electromagnetic shielding technology is difficult to achieve adjustable frequency and shielding efficiency.

[0005] In order to achieve the above-mentioned object, an embodiment of the utility model provides an electromagnetic shielding structure, comprising:

[0006] The first super surface layer;

[0007] A wave-transmitting layer, disposed on one side of the first super surface layer;

[0008] A second super surface layer is arranged on a side of the wave-transmitting layer away from the first super surface layer;

[0009] A control unit, connected to the first super surface layer and the second super surface layer respectively;

[0010] Wherein, the control unit sends an operating frequency control signal to the first supersurface layer, and / or sends a shielding efficiency control signal to the second supersurface layer.

[0011] Optionally, the first supersurface layer comprises:

[0012] a first insulating dielectric layer;

[0013] A first feeding layer, arranged on a side of the first insulating medium layer facing the wave-transmitting layer;

[0014] A first surface layer is arranged on a side of the first insulating medium layer away from the wave-transmitting layer, the first surface layer comprises: at least one first adjustable device and a plurality of first conductors arranged in an array, wherein the first conductor is in a strip shape, the first adjustable device is arranged between two adjacent first conductors whose length extension directions are on the same horizontal line, and the first adjustable device is connected to the first feeding layer;

[0015] The control unit is connected to the first adjustable device, and the control unit sends the operating frequency control signal to the first adjustable device.

[0016] Optionally, the length of the first conductor is greater than or equal to P / 4 and less than or equal to P, and the width of the first conductor is greater than or equal to P / 4 and less than or equal to P / 2, wherein the value range of P is determined according to the adjustable range of the operating frequency.

[0017] Optionally, the distance between two adjacent first conductors whose length extension directions are on different horizontal lines is greater than or equal to P / 6 and less than or equal to P / 2, wherein the value range of P is determined according to the adjustable range of the operating frequency.

[0018] Optionally, the thickness of the first insulating dielectric layer is greater than or equal to P / 20 and less than or equal to P / 15, wherein the value range of P is determined according to the adjustable range of the operating frequency.

[0019] Optionally, the second supersurface layer comprises:

[0020] a second insulating dielectric layer;

[0021] A second feeding layer, arranged on a side of the second insulating medium layer facing the wave-transmitting layer;

[0022] At least two second conductors are arranged on a side of the second insulating medium layer away from the wave-transmitting layer, wherein at least one second adjustable device is arranged between two adjacent second conductors, and the second adjustable device is connected to the second feeding layer;

[0023] Wherein, the control unit is connected to the second adjustable device, and the control unit sends a shielding efficiency control signal to the second adjustable device.

[0024] Optionally, the cross-section of the second conductor is rectangular, wherein the length of the second conductor is greater than or equal to P / 2 and less than or equal to P, and the width of the second conductor is greater than or equal to P / 4 and less than or equal to P / 2, wherein the value range of P is determined according to the adjustable range of the operating frequency.

[0025] Optionally, the thickness of the wave-transmitting layer is greater than or equal to P / 10 and less than or equal to P / 5, wherein the value range of P is determined according to the adjustable range of the operating frequency.

[0026] Optionally, the dielectric constant of the wave-transmitting layer is greater than or equal to 1.

[0027] Optionally, the input current of the first adjustable device in the first metasurface layer and the input current of the second adjustable device in the second metasurface layer are in the same direction.

[0028] The beneficial effects of the above technical solution of the utility model are as follows:

[0029] In the electromagnetic shielding structure of the embodiment of the utility model, the control unit can send an operating frequency control signal to the first super surface layer to adjust the operating frequency of the electromagnetic shielding structure, and can also send a shielding efficiency control signal to the second super surface layer to adjust the shielding efficiency of the electromagnetic shielding structure. In this way, it is possible to selectively adjust the shielding performance of electromagnetic waves of different frequencies according to actual needs, with high control accuracy, a wide frequency range, and fast adjustment speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a schematic structural diagram of the electromagnetic shielding structure of an embodiment of the utility model;

[0031] Figure 2 This is a schematic structural diagram of the first super surface layer of an embodiment of the utility model;

[0032] Figure 3 A schematic structural diagram of the first surface layer in the first super surface layer of an embodiment of the utility model;

[0033] Figure 4 This is a schematic structural diagram of the second super surface layer of an embodiment of the utility model;

[0034] Figure 5 A schematic diagram of the structure of the second surface layer in the second super surface layer of an embodiment of the utility model;

[0035] Figure 6 This is a return loss variation curve of the varactor diode in the second super surface layer of the embodiment of the utility model under different capacitance states (the PIN tube in the first super surface layer is in the OFF state);

[0036] Figure 7 This is a return loss variation curve of the varactor diode in the second super surface layer of an embodiment of the utility model under different capacitance states (the PIN tube in the first super surface layer is in the ON state). DETAILED DESCRIPTION

[0037] In order to make the technical problems to be solved, technical solutions and advantages of the present invention more clear, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0038] It should be understood that the references to "one embodiment" or "an embodiment" throughout the specification mean that the specific features, structures, or characteristics associated with the embodiment are included in at least one embodiment of the present invention. Therefore, the references to "in one embodiment" or "in an embodiment" appearing throughout the specification do not necessarily refer to the same embodiment. In addition, these specific features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0039] In various embodiments of the present invention, it should be understood that the size of the serial numbers of the following processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0040] Additionally, the terms "system" and "network" are often used interchangeably herein.

[0041] In the embodiments provided in the present application, it should be understood that "B corresponding to A" means that B is associated with A, and B can be determined according to A. However, it should also be understood that determining B according to A does not mean determining B only according to A, and B can also be determined according to A and / or other information.

[0042] Related technical description:

[0043] Electromagnetic shielding technology is a technology designed to block or reduce electromagnetic radiation. Its application range covers many fields such as electronic equipment, communication systems, medical equipment, military systems, etc.

[0044] At present, the common electromagnetic shielding method is to use electromagnetic shielding materials (such as ferrite, copper mesh, conductive coating, etc.) to absorb or reflect electromagnetic radiation to reduce the impact range of electromagnetic radiation. When designing electronic equipment or equipment housings, using these materials can effectively reduce the impact of external electromagnetic fields. For large equipment or special needs, a shielding cover or shielding room can be used to place the equipment inside the shielding structure. These structures are usually made of electromagnetic shielding materials and can effectively block external electromagnetic radiation.

[0045] In addition, some electromagnetic shielding methods use special electromagnetic shielding coatings to coat the surface of the equipment to increase the electromagnetic shielding performance of the equipment. These coatings usually contain conductive particles and have a good electromagnetic shielding effect. For some scenarios with very strict requirements on the electromagnetic environment, such as laboratories or production lines, special electromagnetic shielding compartments can be set up to ensure that the equipment is not interfered by external electromagnetic radiation when working in these areas.

[0046] However, traditional electromagnetic shielding technology, especially technical solutions such as electromagnetic shielding materials or the addition of electromagnetic shielding coatings or electromagnetic shielding covers, can often only shield electromagnetic radiation for a specific frequency band. Therefore, when there are multiple frequency radiation sources in the environment, the disadvantages of traditional electromagnetic shielding technology begin to emerge. Moreover, since traditional electromagnetic shielding technology is only applicable to radiation sources of a specific type or frequency range, it is usually static. Therefore, it is difficult to effectively change the frequency that needs to be shielded according to demand, and it is also difficult to adjust its performance in real time to adapt to changes in the frequency of electromagnetic radiation in the environment, resulting in the traditional electromagnetic shielding technology. The shielding effect for broad-spectrum radiation sources may be relatively poor.

[0047] Frequency-adjustable electromagnetic shielding technology requires an efficient frequency adjustment mechanism, which is extremely difficult to achieve accurate and rapid frequency adjustment. Most of the few frequency-adjustable electromagnetic shielding solutions currently available are based on special material synthesis and manufacturing processes, and are adjusted and implemented by electrical and mechanical adjustment in combination with material properties. However, these solutions place additional requirements on the production and processing of existing electromagnetic shielding materials, resulting in high production costs, which limits the promotion and application of the technology. In addition, when facing practical applications, the complexity of various engineering implementations and application scenarios must also be considered, including integration with equipment and the environment, frequency-adjustable implementation methods, and safety of use.

[0048] In summary, the practical application of frequency-selectable electromagnetic shielding technology needs to consider cost-effectiveness and scalability to ensure that the technology can be commercialized and applied on a large scale. However, the existing electromagnetic shielding technology is difficult to achieve adjustable frequency and shielding efficiency, and it is difficult to meet the needs of practical applications.

[0049] like Figure 1 As shown, an electromagnetic shielding structure of an embodiment of the utility model includes:

[0050] The first super surface layer 1;

[0051] A wave-transmitting layer 2, arranged on one side of the first super surface layer 1;

[0052] A second super surface layer 3 is arranged on a side of the wave-transmitting layer 2 away from the first super surface layer 1;

[0053] A control unit is connected to the first supersurface layer 1 and the second supersurface layer 3 respectively; wherein the control unit sends an operating frequency control signal to the first supersurface layer 1 and / or sends a shielding efficiency control signal to the second supersurface layer 3.

[0054] It should be noted that the electromagnetic shielding structure is a frequency-selective supersurface structure with adjustable shielding efficiency, wherein the first supersurface layer 1 (i.e., the frequency switching layer) has an operating frequency switching function, and the second supersurface layer 3 (i.e., the shielding efficiency adjustment layer) has a shielding efficiency adjustment function. Specifically, the first supersurface layer 1 and the second supersurface layer 3 are placed in an overlapping manner, and a wave-transmitting layer 2 is arranged between the two, and a control signal (including an operating frequency control signal and a shielding efficiency control signal) is sent to the first supersurface layer 1 and / or the second supersurface layer 3 by a control unit, so that the operating frequency and the shielding efficiency can be adjusted.

[0055] Among them, the operating frequency control signal is used to adjust the operating frequency of the electromagnetic shielding structure. After the first super surface layer 1 receives the operating frequency control signal, the operating frequency of the electromagnetic shielding structure can be adjusted; the shielding efficiency control signal is used to adjust the shielding efficiency of the electromagnetic shielding structure. The second super surface layer 3 receives the shielding efficiency control signal and can adjust the shielding efficiency of the electromagnetic shielding structure. In this way, the electromagnetic shielding structure can adapt to the changes of different frequencies more flexibly, which helps to better adapt to a wide range of electromagnetic spectrum.

[0056] In this embodiment, the control unit can send an operating frequency control signal to the first super surface layer 1 to adjust the operating frequency of the electromagnetic shielding structure, and can also send a shielding efficiency control signal to the second super surface layer 3 to adjust the shielding efficiency of the electromagnetic shielding structure. In this way, it is possible to selectively adjust the shielding performance of electromagnetic waves of different frequencies according to actual needs, with high control accuracy, a wide frequency range, and fast adjustment speed.

[0057] It should be noted that the electromagnetic shielding structure of the embodiment of the utility model can be specifically an arrangement structure composed of a plurality of super surface units, wherein each super surface unit includes the following: Figure 1 The first super surface layer 1, the wave-transmitting layer 2 and the second super surface layer 3 shown, the period of the super surface unit is represented by P, and the value range of P is determined according to the adjustable range of the working frequency, which is specifically described as follows:

[0058] Assume that the working frequency of the electromagnetic shielding structure (that is, the frequency band of the electromagnetic wave in which the electromagnetic shielding structure acts, that is, the electromagnetic shielding structure can shield the electromagnetic waves in this frequency band) is f, f∈[f1, f2], and the center frequency is f ′ =(f1+f2) / 2, the wavelength of the electromagnetic wave λ = c / f ′ , P∈[λ / 8,λ / 2]. Where λ represents the wavelength of the electromagnetic wave, c represents the speed of light propagation under vacuum conditions, and f ′ Indicates the center frequency.

[0059] It should be noted that if P is less than λ / 8, or P is greater than λ / 2, the electromagnetic shielding structure may not respond to electromagnetic waves, and the electromagnetic wave shielding effect cannot be achieved.

[0060] like Figure 2-Figure 3 As shown, in some embodiments, the first super surface layer 1 includes:

[0061] A first insulating dielectric layer 101;

[0062] A first feeding layer 102, arranged on a side of the first insulating medium layer 101 facing the wave-transmitting layer 2;

[0063] The first surface layer 103 is arranged on the side of the first insulating medium layer 101 away from the wave-transmitting layer 2, and the first surface layer includes: at least one first adjustable device 1032 and a plurality of first conductors 1031 arranged in an array, wherein the first conductors 1031 are in a strip shape, the first adjustable device 1032 is arranged between two adjacent first conductors 1031 whose length extension directions are on the same horizontal line, and the first adjustable device 1032 is connected to the first feeding layer; wherein the control unit is connected to the first adjustable device 1032, and the control unit sends the operating frequency control signal to the first adjustable device 1032.

[0064] Here, the first adjustable device 1032 includes but is not limited to the following devices: PIN diodes, varactors, and micro-electro-mechanical systems (MEMS) actuated switches. The operating frequency control signal is used to adjust at least one electrical parameter (such as capacitance, inductance, resistance, etc.) of the first adjustable device 1032, so as to adjust the operating frequency of the electromagnetic shielding structure. After receiving the operating frequency control signal, the first adjustable device 1032 will adjust at least one electrical parameter of the first adjustable device 1032 according to the operating frequency control signal. In this way, by adjusting at least one of the electrical parameters such as capacitance, inductance, and resistance variables of the first adjustable device 1032 in the first metasurface layer 1, the frequency band of the electromagnetic wave acting on the electromagnetic shielding structure can be adjusted.

[0065] It should be noted that if Figure 2 As shown, in the first super surface layer 1, the first insulating dielectric layer 101 serves as an intermediate layer, which can effectively isolate the first feed layer 102 from the first surface layer 103 to avoid short circuit. As a preferred embodiment, the value range of the dielectric constant (ε1) of the first insulating dielectric layer 101 can be expressed as: ε1∈[2,6], and the value range of the loss tangent (tanδ1) of the first insulating dielectric layer 101 can be expressed as: tanδ1∈[0.001,0.05].

[0066] The main function of the first feeding layer 102 is to set the feeding network according to the position of the first adjustable device 1032. As a preferred embodiment, the first feeding layer 102 can be made of a material with good conductor properties, for example, a material with a conductivity greater than or equal to 1.0×10 7 Material of S / m.

[0067] In some embodiments, the thickness of the first insulating dielectric layer 101 is greater than or equal to P / 20 and less than or equal to P / 15.

[0068] like Figure 2 As shown, as a preferred embodiment, the value range of the thickness (H1) of the first insulating dielectric layer 101 can be expressed as: H1∈[P / 20, P / 15].

[0069] In some embodiments, the length of the first conductor 1031 is greater than or equal to P / 4 and less than or equal to P, and the width of the first conductor 1031 is greater than or equal to P / 4 and less than or equal to P / 2.

[0070] It should be noted that the first conductor 1031 may be made of a material having good conductor properties, for example, a material having a conductivity greater than or equal to 1.0×10 7 S / m materials. Figure 3 As shown, in some preferred embodiments, the value range of the length (L) of the first conductor 1031 can be expressed as: L∈[P / 4, P], and the value range of the width (W) of the first conductor 1031 can be expressed as: W∈[P / 4, P / 2].

[0071] In some embodiments, the distance between two adjacent first conductors 1031 whose length extension directions are on different horizontal lines is greater than or equal to P / 6 and less than or equal to P / 2.

[0072] In a specific preferred embodiment, Figure 3 As shown, in one of the above-mentioned metasurface units, the first surface layer 103 of the first metasurface layer 1 is provided with three columns of first conductors 1031, and the first conductors 1031 in different columns are parallel to each other, and the value range of the spacing (D2) between the first conductors 1031 in two adjacent columns can be expressed as: D2∈[P / 6, P / 2]. In the second column in the middle position, the length extension directions of the two first conductors 1031 are on the same horizontal line, and the middle load is loaded with a first adjustable device 1032. In other words, the first adjustable device 1032 is provided between two adjacent first conductors 1031 whose length extension directions are on the same horizontal line, and the value range of the spacing (D1) between the two first conductors 1031 can be expressed as: D1∈[0, P / 2].

[0073] In some embodiments, the thickness of the wave-transmitting layer 2 is greater than or equal to P / 10 and less than or equal to P / 5.

[0074] In some embodiments, the dielectric constant of the wave-transmitting layer 2 is greater than or equal to 1.

[0075] It should be noted that, in some optional examples, the wave-transmitting layer 2 may be made of a material close to the air impedance characteristics (i.e., a wave-transmitting medium), and in other optional examples, the wave-transmitting layer 2 may also be a structure with a space left inside, that is, the wave-transmitting layer 2 may be a space gap reserved between the first super surface layer 1 and the second super surface layer 3. In a preferred embodiment, the value range of the thickness (H2) of the wave-transmitting layer 2 can be expressed as: H2∈[P / 10, P / 5], the value range of the dielectric constant (ε2) of the wave-transmitting layer 2 can be expressed as: ε2∈[1,∞], and the value range of the magnetic permeability (μ2) of the wave-transmitting layer 2 can be expressed as: μ2∈[1,1.5].

[0076] like Figure 4-Figure 5 As shown, in some embodiments, the second super surface layer 3 includes:

[0077] A second insulating dielectric layer 301;

[0078] A second feeding layer 302, arranged on a side of the second insulating medium layer 301 facing the wave-transmitting layer 2;

[0079] The second surface layer 303 includes: at least two second conductors 3031, which are arranged on the side of the second insulating medium layer 301 away from the wave-transmitting layer 2, wherein at least one second adjustable device 3032 is arranged between two adjacent second conductors 3031, and the second adjustable device 3032 is connected to the second feeding layer 302; wherein the control unit is connected to the second adjustable device 3032, and the control unit sends a shielding efficiency control signal to the second adjustable device 3032.

[0080] Here, the second adjustable device 3032 includes but is not limited to the following devices: PIN diode, varactor, MEMS actuated switch. The shielding efficiency control signal is used to adjust at least one electrical parameter (such as capacitance, inductance, resistance, etc.) of the second adjustable device 3032, so as to adjust the shielding efficiency of the electromagnetic shielding structure. After receiving the shielding efficiency control signal, the second adjustable device 3032 will adjust at least one electrical parameter of the second adjustable device 3032 according to the shielding efficiency control signal. In this way, by adjusting at least one of the electrical parameters such as capacitance, inductance, resistance variables of the adjustable device of the second adjustable device 3032, the reflection amplitude of the electromagnetic wave in the action frequency band of the electromagnetic shielding structure can be regulated (amplitude modulation), so as to achieve the effect of regulating the shielding efficiency of the electromagnetic shielding structure.

[0081] It should be noted that the main function of the second feeding layer 302 is to set the feeding network according to the position of the second adjustable device 3032. As a preferred embodiment, the second feeding layer 302 can be made of a material with good conductor properties, for example, a material with a conductivity greater than or equal to 1.0×10 7 Material of S / m.

[0082] It should also be noted that if Figure 4 As shown, in the second super surface layer 3, the second insulating dielectric layer 301 is used as an intermediate layer to effectively isolate the second feed layer 302 from the second surface layer 303 to avoid short circuit. As a preferred embodiment, the value range of the dielectric constant (ε3) of the second insulating dielectric layer 301 can be expressed as: ε3∈[2,6], the value range of the loss tangent (tanδ3) of the second insulating dielectric layer 301 can be expressed as: tanδ3∈[0.001,0.05], and the value range of the thickness (H3) of the second insulating dielectric layer 301 can be expressed as: H3∈[P / 4,P / 2].

[0083] In some embodiments, the cross-section of the second conductor 3031 is rectangular, wherein the length of the second conductor 3031 is greater than or equal to P / 2 and less than or equal to P, and the width of the second conductor 3031 is greater than or equal to P / 4 and less than or equal to P / 2.

[0084] In a specific preferred embodiment, Figure 5 As shown, in one of the above-mentioned metasurface units, the second surface layer 303 of the second metasurface layer 3 includes two second conductors 3031 of rectangular structure, and the two second conductors 3031 are cascaded with the second adjustable device 3032 to form the second surface layer 303. Among them, the value range of the length (A) of the second conductor 3031 can be expressed as: A∈[P / 2, P], and the value range of the width (B) of the second conductor 3031 can be expressed as: B∈[P / 4, P / 2].

[0085] In some embodiments, the input current of the first adjustable device 1032 in the first metasurface layer 1 and the input current of the second adjustable device 3032 in the second metasurface layer 3 are in the same direction.

[0086] In a specific embodiment of the present application, the electromagnetic shielding structure is constructed with the following parameters: P=12mm, W=2mm and 1.6mm, D2=3.2mm, D1=1.1mm, L=12mm and 5.45mm, ε1=ε3=4.4, tanδ1=tanδ3=0.025, H1=0.6mm, H2=1.4mm, ε2=1, μ2=1, H3=3.3mm, A=11mm, B=5mm.

[0087] By adjusting the capacitance and voltage of the adjustable components (including the first adjustable component 1032 and the second adjustable component 3032 ), an S11 parameter curve (ie, a return loss curve) can be obtained in the simulation software.

[0088] According to the S parameter testing method, the S11 parameter is used to represent the return loss, wherein the closer the S11 value is to 1, the more electromagnetic waves are reflected, and the electromagnetic waves cannot penetrate the electromagnetic shielding structure, that is, the electromagnetic shielding efficiency of the electromagnetic shielding structure is good; the closer the S11 value is to 0, the more electromagnetic waves are transmitted, that is, the electromagnetic shielding efficiency of the electromagnetic shielding structure is poor.

[0089] like Figure 6 As shown, when the first adjustable device 1032 (such as a PIN tube) in the first metasurface layer 1 is in an off state, the second adjustable device 3032 (such as a varactor diode) in the second metasurface layer 3 is in different capacitance (0.13 to 2.6 pF) states. It can be seen that when the capacitance changes from 2.6 pF to 0.13 pF, as the capacitance decreases, within the frequency range of 5.9 to 6.3 GHz, the shielding efficiency changes from 0.8 to 0.2, that is, the electromagnetic shielding efficiency drops from 80% to 20%.

[0090] like Figure 7 As shown, when the first adjustable device 1032 (such as a PIN tube) on the first metasurface layer 1 is in the ON state, the second adjustable device 3032 (such as a varactor diode) on the second metasurface layer 3 is in different capacitance (0.13-2.6pF) states. It can be seen that when the capacitance changes from 2.6pF to 0.13pF, as the capacitance decreases, within the frequency range of 3.6-4.2GHz, the shielding efficiency changes from 0.95 to about 0.6, that is, the electromagnetic shielding efficiency drops from 95% to 60%.

[0091] By comparison Figure 6 and Figure 7 It can be found that when the first adjustable device 1032 on the first supersurface layer 1 is switched between the open / closed state, electromagnetic waves of different frequency bands (3.6~4.2GHz, 5.9~6.3GHz) can be shielded. Adjusting the varactor diode of the second supersurface layer 3 can cause changes in different reflection amplitudes, thereby achieving the effect of regulating the shielding efficiency.

[0092] Therefore, combined with the above simulation results, by controlling the adjustable device, the electromagnetic shielding structure can be switched at different operating frequencies, and the shielding efficiency of electromagnetic waves within the operating frequency can be adjusted within a certain range, which broadens the application scenarios of smart metasurfaces and effectively solves the problem of frequency switching and dynamic adjustment of shielding efficiency.

[0093] It should be noted that, through the above electromagnetic shielding structure, the operating frequency and shielding efficiency can be adjusted in real time in a dynamic electromagnetic environment, so as to provide the best shielding performance. In this way, the above electromagnetic shielding structure has broad application prospects in various fields such as military and civilian. For example, in the military field, the frequency selectability of the electromagnetic shielding structure can be used to dynamically adjust radar waves of different frequencies, which helps to improve the efficiency of target detection and tracking; for example, in the civilian field, for IoT devices, there are many communication protocols used (different operating frequencies), and the frequency selectability of the electromagnetic shielding structure can be used to optimize signal transmission and improve the communication efficiency between devices; in addition, for some special confidentiality or wireless communication scenarios, electromagnetic security is very important. The frequency adjustable characteristics of the electromagnetic shielding structure can ensure the penetration of electromagnetic waves in a specific frequency band, and can prevent the transmission of unauthorized (non-specific frequency band) electromagnetic waves, causing information security leakage, and avoiding potential eavesdropping risks.

[0094] The electromagnetic shielding structure of this embodiment combines the characteristics of intelligent metasurface technology that can change the electromagnetic propagation characteristics. By separately controlling the adjustable devices on different layers, the shielding efficiency of electromagnetic waves in different frequency bands can be selectively controlled, thereby realizing electromagnetic shielding functions with adjustable frequency and adjustable shielding efficiency. It has high control accuracy, a wide frequency range, and a fast adjustment speed.

[0095] The above exemplary embodiments are described with reference to the accompanying drawings, and many different forms and embodiments are feasible without departing from the spirit and teachings of the utility model. Therefore, the utility model should not be constructed as a limitation of the exemplary embodiments proposed herein. More specifically, these exemplary embodiments are provided so that the utility model will be perfect and complete, and the scope of the utility model will be conveyed to those who are familiar with the technology. In these figures, the component sizes and relative sizes may be exaggerated for clarity. The terms used here are only based on the purpose of describing specific exemplary embodiments and are not intended to be limiting. As used herein, unless the context clearly indicates otherwise, the singular forms "one", "an" and "the" are intended to include these multiple forms. It will be further understood that the terms "including" and / or "comprising" when used in this specification indicate the presence of the features, integers, steps, operations, components and / or components, but do not exclude the presence or increase of one or more other features, integers, steps, operations, components, components and / or their groups. Unless otherwise indicated, when stated, a range of values ​​includes the upper and lower limits of that range and any subranges therebetween.

[0096] The above is a preferred embodiment of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. An electromagnetic shielding structure, characterized in that: include: The first super surface layer; A wave-transmitting layer, disposed on one side of the first super surface layer; A second super surface layer is arranged on a side of the wave-transmitting layer away from the first super surface layer; a control unit, connected to the first supersurface layer and the second supersurface layer respectively; Wherein, the control unit sends an operating frequency control signal to the first supersurface layer, and / or sends a shielding efficiency control signal to the second supersurface layer.

2. The electromagnetic shielding structure according to claim 1, characterized in that: The first super surface layer comprises: a first insulating dielectric layer; A first feeding layer, arranged on a side of the first insulating medium layer facing the wave-transmitting layer; A first surface layer is arranged on a side of the first insulating medium layer away from the wave-transmitting layer, the first surface layer comprises: at least one first adjustable device and a plurality of first conductors arranged in an array, wherein the first conductor is in a strip shape, the first adjustable device is arranged between two adjacent first conductors whose length extension directions are on the same horizontal line, and the first adjustable device is connected to the first feeding layer; The control unit is connected to the first adjustable device, and the control unit sends the operating frequency control signal to the first adjustable device.

3. The electromagnetic shielding structure according to claim 2, characterized in that: The length of the first conductor is greater than or equal to P / 4 and less than or equal to P, and the width of the first conductor is greater than or equal to P / 4 and less than or equal to P / 2, wherein the value range of P is determined according to the adjustable range of the operating frequency.

4. The electromagnetic shielding structure according to claim 2, characterized in that: The distance between two adjacent first conductors whose length extension directions are on different horizontal lines is greater than or equal to P / 6 and less than or equal to P / 2, wherein the value range of P is determined according to the adjustable range of the operating frequency.

5. The electromagnetic shielding structure according to claim 2, characterized in that: The thickness of the first insulating dielectric layer is greater than or equal to P / 20 and less than or equal to P / 15, wherein the value range of P is determined according to the adjustable range of the operating frequency.

6. The electromagnetic shielding structure according to claim 1, characterized in that: The second super surface layer comprises: a second insulating dielectric layer; A second feeding layer, arranged on a side of the second insulating medium layer facing the wave-transmitting layer; At least two second conductors are arranged on a side of the second insulating medium layer away from the wave-transmitting layer, wherein at least one second adjustable device is arranged between two adjacent second conductors, and the second adjustable device is connected to the second feeding layer; Wherein, the control unit is connected to the second adjustable device, and the control unit sends a shielding efficiency control signal to the second adjustable device.

7. The electromagnetic shielding structure according to claim 6, characterized in that: The cross-section of the second conductor is rectangular, wherein the length of the second conductor is greater than or equal to P / 2 and less than or equal to P, and the width of the second conductor is greater than or equal to P / 4 and less than or equal to P / 2, wherein the value range of P is determined according to the adjustable range of the operating frequency.

8. The electromagnetic shielding structure according to claim 1, characterized in that: The thickness of the wave-transmitting layer is greater than or equal to P / 10 and less than or equal to P / 5, wherein the value range of P is determined according to the adjustable range of the operating frequency.

9. The electromagnetic shielding structure according to claim 1, characterized in that: The dielectric constant of the wave-transmitting layer is greater than or equal to 1.

10. The electromagnetic shielding structure according to claim 1, characterized in that: The input current of the first adjustable device in the first super-surface layer and the input current of the second adjustable device in the second super-surface layer have the same direction.

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