A wave absorbing structure

Abstract

The present invention provides an absorbing structure, comprising a dielectric substrate layer, a conductor structure layer arranged on one surface of the dielectric substrate layer, and a conductor reflection layer arranged on the other surface of the dielectric substrate layer; the conductor structure layer comprises a first structure, the first structure comprises an outer frame and a central structure located in the outer frame; the outer frame comprises N strip structures, and N integrated conductors connected between every two adjacent strip structures in the N strip structures; the central structure comprises a primary substructure and a secondary substructure; both the primary substructure and the secondary substructure are axisymmetric structures; the primary substructure comprises two sides and a waist connecting the two sides, each side having at least two ends; the secondary substructure comprises two sides and a waist connecting the two sides, each side having at least one end; each of the ends included in the primary substructure is connected to the waist of the secondary substructure, and the size of the primary substructure is larger than that of the secondary substructure. The absorbing structure realizes absorption of electromagnetic waves of a specific frequency.

Description

Technical Field

[0001] The invention relates to the technical field of electromagnetic wave absorbing materials, and in particular to a wave absorbing structure. Background Art

[0002] With the continuous development of communication technology, devices can send signals through electromagnetic waves to communicate with each other. Different devices use different spectrum resources for communication. For example, medium frequency resources are used for maritime wireless communication, AM broadcasting, etc.; ultra-high frequency resources are used for cellular TV, navigation, radar, microwave communication, personal communication systems, etc.

[0003] At present, communication devices working at certain specific frequencies have been rapidly applied and developed. For example, in order to facilitate people's lives, WiFi technology has been widely used. WiFi signals are transmitted through electromagnetic waves with frequencies of 2.4GHz and / or 5GHz. At present, most electronic devices have integrated the function of wireless network cards to facilitate the reception of WiFi signals in the surrounding environment. Users can communicate wirelessly through WiFi signals, which provides great convenience for people's lives. However, while people enjoy this convenience, they are also subject to some adverse factors. The WiFi signals flooding the environment may interfere with people's other communication functions, such as the video call function and data transmission function of the 5G network, affecting the user's network communication experience.

[0004] Therefore, for certain application scenarios, designing an absorbing material that can effectively absorb electromagnetic waves of certain specific frequencies becomes an urgent problem to be solved. Summary of the invention

[0005] An embodiment of the present invention provides a wave absorbing structure, which is used to absorb electromagnetic waves of a specific frequency.

[0006] A wave absorbing structure comprises: a dielectric substrate layer, a conductor structure layer arranged on one surface of the dielectric substrate layer, and a conductor reflection layer arranged on the other surface of the dielectric substrate layer; the conductor structure layer comprises a first structure, the first structure comprises an outer frame and a central structure located in the outer frame; the outer frame comprises N strip structures and N lumped resistors; each of the N lumped resistors is connected between every two adjacent strip structures in the N strip structures; the central structure comprises a primary substructure and a secondary substructure; both the primary substructure and the secondary substructure are axisymmetric structures; the primary substructure comprises two side portions and a waist portion connecting the two side portions, each of the side portions of the primary substructure has at least two ends; the secondary substructure comprises two side portions and a waist portion connecting the two side portions, each of the side portions of the secondary substructure has at least one end; each of the ends included in the primary substructure is connected to the waist of the secondary substructure, and the size of the primary substructure is larger than that of the secondary substructure.

[0007] In a possible implementation, the primary substructure and the secondary substructure are both H-shaped structures, the central structure also includes a tertiary substructure, each of the ends of the secondary substructure is connected to the tertiary substructure, the tertiary substructure is an axisymmetric structure, and the tertiary substructure includes two sides and a waist connecting the two sides, each of the sides of the tertiary substructure has at least one end; the size of the secondary substructure is larger than that of the tertiary substructure.

[0008] In a possible implementation, the absorbing structure is a square structure, and the absorbing structure also includes a second structure, a third structure and a fourth structure; the first structure and the fourth structure are centrally symmetric about the center point of the conductor structure layer; the second structure is: the center point of the first structure is a structure obtained by rotating the center 90 degrees; the second structure and the third structure are centrally symmetric about the center point of the conductor structure layer.

[0009] In a possible implementation manner, the tertiary substructure is an H-shaped structure or a concave structure.

[0010] In a possible implementation, the side length of the absorbing structure is 18 mm-22 mm; the outer frame is square, and the side length of the outer frame is in the range of 14 mm-16 mm; the width of the outer frame is in the range of 0.5 mm-1.5 mm.

[0011] In a possible implementation, the outer frame is square, N is 4, each lumped resistor connects two adjacent strip structures, and each lumped resistor is arranged at a corner of the outer frame.

[0012] In a possible implementation, the primary substructure includes a first side and a second side parallel to each other, and a waist perpendicular to the first side and the second side; the width of the waist ranges from 0.1mm to 0.7mm; the length of the waist ranges from 5mm to 7mm.

[0013] In a possible implementation manner, the total resistance of the N lumped resistors ranges from 12.5Ω to 50Ω.

[0014] In a possible implementation, the thickness of the dielectric substrate layer ranges from 5 mm to 8 mm.

[0015] In a possible implementation, the dielectric constant of the dielectric substrate layer is 3.2-4.5

[0016] In an embodiment of the present invention, the dielectric substrate layer is used to carry the conductor structure layer and the conductor reflection layer, the conductor structure layer is used to absorb incident electromagnetic waves, and the conductor structure layer includes a first structure, the first structure includes an outer frame and a central structure located in the outer frame; the central structure is used to sense the outer frame when there is an incident electromagnetic wave on the conductor structure layer, and the conductor structure layer generates current. The central structure includes a primary substructure and a secondary substructure; the primary substructure is the main structure, the end of the primary substructure is the connection point, and the next level structure is fractalized, the end of the primary substructure is connected to the waist of the secondary substructure, and each end of the secondary substructure has at least one end to ensure that the secondary substructure is not a closed structure. The conductor pattern in the conductor structure in the embodiment of the present invention can form multiple electromagnetic bandgap responses, and the structure can be equivalent to a series-parallel circuit of multiple distributed capacitors and inductors. Specifically, for the primary substructure (such as an H-shaped structure), when the electric field is polarized in the horizontal direction, the waist of the primary substructure can form an induced current distribution under the polarization of the electric field, which is equivalent to an inductor structure, and a capacitance distribution will be formed correspondingly at the angle between the edge and the waist of the primary substructure, so it is equivalent to a parallel circuit of capacitors and inductors. The structure in which the primary substructure is connected to the secondary substructure 1132 extends the length of the conductor pattern path. This structure is equivalent to increasing the length of the geometric space of the inductor part and the area of ​​spatial capacitance distribution, which is equivalent to a series-parallel circuit of multiple inductors and capacitors. Due to the magnetic induction of the central structure and the outer frame, the outer frame generates an induced current. The outer frame includes N strip structures and N integrated conductors. The induced current generated by the outer frame is absorbed by the lumped resistance, generating electromagnetic energy loss, thereby absorbing electromagnetic waves of a specific frequency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention, and a person skilled in the art can also obtain other drawings based on these drawings.

[0018] Figure 1 This is a schematic diagram of a three-dimensional structure of an embodiment of a wave absorbing structure in an embodiment of the present invention;

[0019] Figure 2 It is a schematic diagram of a side view structure of an embodiment of a wave absorbing structure in an embodiment of the present invention;

[0020] Figure 3 A schematic diagram of an embodiment of a primary substructure and a secondary substructure provided by an embodiment of the present invention;

[0021] Figure 4 A schematic diagram of another embodiment of a primary substructure provided by an embodiment of the present invention;

[0022] Figure 5 A schematic diagram of another embodiment of a primary substructure provided by an embodiment of the present invention;

[0023] Figure 6 A schematic diagram of another embodiment of a three-level substructure provided by an embodiment of the present invention;

[0024] Figure 7 A schematic diagram of another embodiment of a three-level substructure provided by an embodiment of the present invention;

[0025] Figure 8 A schematic diagram of another embodiment of a conductor structure layer provided by an embodiment of the present invention;

[0026] Fig. 9 It is a curve schematic diagram of the change of frequency-reflectivity with the change of the side length p of the absorbing structure in the embodiment of the present invention;

[0027] Fig.10 It is a curve diagram showing the corresponding frequency-reflectivity change when the width w1 of the outer frame portion changes in the embodiment of the present invention;

[0028] Fig.11 It is a curve diagram showing the corresponding frequency-reflectivity change when the width w2 of the primary substructure changes in the embodiment of the present invention;

[0029] Fig.12 It is a curve diagram showing the corresponding frequency-reflectivity change when the side length l1 of the outer frame in the embodiment of the present invention changes;

[0030] Fig.13 It is a curve diagram showing the corresponding frequency-reflectivity change when the length l2 of the waist of the primary substructure in the embodiment of the present invention changes;

[0031] Fig.14 It is a curve diagram of the corresponding frequency-reflectivity change when the lumped resistance R0 changes in the embodiment of the present invention;

[0032] Fig.15 It is a schematic diagram of a curve of corresponding frequency-reflectivity change when the thickness h of the dielectric substrate layer changes in an embodiment of the present invention;

[0033] Fig.16 is the dielectric constant e of the dielectric substrate layer in the embodiment of the present invention r Schematic diagram of the corresponding frequency-reflectivity change curve when changes occur;

[0034] Fig.17 Schematic diagram of the curve of the corresponding frequency-reflectivity change when the electromagnetic wave is incident on the surface of the absorbing material at different angles in the TE mode in the embodiment of the present invention;

[0035] Fig.18 Schematic diagram of the corresponding frequency-reflectivity curve change when the electromagnetic wave is incident on the surface of the absorbing structure at different angles in the TM mode in an embodiment of the present invention.

[0036] Among them, the reference numerals in the figure are:

[0037] 1-conductor structure layer; 11-first structure; 111-outer frame; 112-lumped resistor; 113-central structure; 1131-first substructure; 1132-second substructure; 1133-third substructure;

[0038] 12- Second structure;

[0039] 13- The third structure;

[0040] 14- Fourth structure;

[0041] 2- dielectric substrate layer;

[0042] 3- Conductor reflective layer. DETAILED DESCRIPTION

[0043] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0044] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0045] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0046] See also Figure 1 and Figure 2 To understand, Figure 1 is a schematic diagram of a three-dimensional structure of an embodiment of a wave absorbing structure in an embodiment of the present invention, Figure 2 The side view structural diagram of an embodiment of an absorbing structure in an embodiment of the present invention. The absorbing structure includes a dielectric substrate layer 2, a conductor structure layer 1 disposed on one surface of the dielectric substrate layer 2, and a conductor reflection layer 3 disposed on the other surface of the dielectric substrate layer 2; wherein the conductor structure layer 1 is used to absorb electromagnetic waves incident on the surface of the conductor structure layer 1, and the conductor structure layer 1 can also be understood as a film with a pattern printed on the conductor, and the conductor structure layer 1 can also be called a conductor pattern layer, and the conductor structure layer 1 can be equivalent to a resonant circuit. The dielectric substrate layer 2 is used to carry the conductor structure layer 1 and the conductor reflection layer 3. The conductor reflection layer 3 is used to shield electromagnetic waves incident on the absorbing structure. The electromagnetic waves propagate from one side of the space to the other side of the space. When the electromagnetic waves that are not attenuated reach the surface of the conductor reflection layer 3, they are reflected by the conductor reflection layer 3 to achieve the effect of shielding electromagnetic waves.

[0047] For details, please refer to Figure 3 To understand, Figure 3Schematic diagram of a primary substructure and a secondary substructure. The conductor structure layer 1 includes a first structure 11, the first structure 11 includes an outer frame portion 111 and a central structure 113 located in the outer frame portion 111; the outer frame portion 111 includes N strip structures and N lumped resistors 112; each lumped resistor 112 in the N lumped resistors is connected between every two adjacent strip structures in the N strip structures, N is an even number greater than or equal to 4, for example, N is 4, or 8, etc.; the central structure 113 includes a primary substructure 1131 and a secondary substructure 1132; Both the primary substructure 1131 and the secondary substructure 1132 are axially symmetrical structures. The primary substructure 1131 includes two sides and a waist connecting the two sides, and each side has at least two ends; the secondary substructure 1132 includes two sides and a waist connecting the two sides, and each side has at least one end; each of the ends included in the primary substructure 1131 is connected to the waist of the secondary substructure 1132, and the size of the primary substructure 1131 is larger than that of the secondary substructure 1132.

[0048] In the embodiment of the present invention, the primary substructure 1131 includes a first side portion and a second side portion, both of which can be straight strip structures, and the waist can be a straight strip structure, one end of the waist is vertically connected to the first side portion, and the other end of the waist is vertically connected to the second side portion. Figure 3 As shown, the primary substructure 1131 may be an H-shaped structure. Alternatively, the primary substructure 1131 may also be an I-shaped structure. Alternatively, in another possible implementation, see Figure 4 and Figure 5 It is understood that the first side and the second side are both broken line structures with an angle, and the value range of the angle is (120°, 180°). The waist is a straight strip structure, one end of the waist is connected to the angular position of the first side, and the other end of the waist is connected to the angular position of the second side.

[0049] The secondary substructure 1132 may be an H-shaped structure or an I-shaped structure. Figure 3 It is understood that the secondary substructure 1132 may also be a concave structure, the concave structure includes a first side portion, a second side portion and a waist portion, the first end of the first side portion is vertically connected to the first end of the waist portion, and the first end of the second side portion is vertically connected to the first end of the waist portion. Alternatively, in another possible implementation, the secondary substructure 1132 may also be Figure 4 and Figure 5 The structure shown (hereinafter referred to as the double-headed arrow structure).

[0050] In the embodiment of the present invention, the dielectric substrate layer 2 is used to carry the conductor structure layer 1 and the conductor reflection layer 3, the conductor structure layer is used to absorb the incident electromagnetic waves, the conductor structure layer 1 includes a first structure 11, the first structure 11 includes an outer frame 111 and a central structure 113 located in the outer frame 111; the central structure 113 includes a primary substructure 1131 and a secondary substructure 1132; for example, the primary substructure 1131 is an H-shaped structure, with the primary substructure 1131 as the main structure, the primary substructure 1131 includes 4 ends, and the 4 ends of the main structure are used as connection points to fractalize the next level structure, each of the 4 ends of the primary substructure 1131 is connected to the waist of the secondary substructure 1132, and each end of the secondary substructure 1132 has at least one end, ensuring that the secondary substructure 1132 is not a closed structure. The conductor pattern in the conductor structure in the embodiment of the present invention can form multiple electromagnetic bandgap responses, and the structure can be equivalent to a series-parallel circuit of multiple distributed capacitors and inductors. Specifically, for the primary substructure 1131 (such as an H-shaped structure), when the electric field is polarized in the horizontal direction, the waist of the H-shaped structure can form an induced current distribution under the polarization of the electric field, which is equivalent to an inductor structure, and a capacitance distribution will be formed correspondingly at the angle between the edge and the waist of the H-shaped structure, so it is equivalent to a parallel circuit of capacitors and inductors. The structure in which the primary substructure 1131 is connected to the secondary substructure 1132 extends the length of the conductor pattern path. This structure is equivalent to increasing the length of the geometric space of the inductor part and the area of ​​spatial capacitance distribution, which is equivalent to a series-parallel circuit of multiple inductors and capacitors. Due to the magnetic induction of the central structure 113 and the outer frame 111, the outer frame 111 generates an induced current. The outer frame 111 includes N strip structures and N integrated conductors. The induced current generated by the outer frame 111 is absorbed by the lumped resistor 112, generating electromagnetic energy loss, thereby absorbing electromagnetic waves of a specific frequency.

[0051] Optionally, in one possible embodiment, see Figure 6 and Figure 7 It is understood that the primary substructure 1131 and the secondary substructure 1132 are both H-shaped structures, the central structure 113 also includes a tertiary substructure 1133, each of the four ends of the secondary substructure 1132 is connected to the tertiary substructure 1133, the tertiary substructure 1133 is an axisymmetric structure, and the tertiary substructure 1133 includes two sides and a waist connecting the two sides, each side has at least one end; the size of the secondary substructure 1132 is larger than that of the tertiary substructure 1133. The tertiary substructure 1133 can be an H-shaped structure, a concave structure, or a bidirectional arrow-shaped structure.

[0052] It should be noted that, in the embodiment of the present invention, the central structure can be a combination of an H-shaped structure, a concave structure, and a double-arrow-shaped structure. For example, the primary substructure 1131 is an H-shaped structure, the secondary substructure 1132 is a concave structure, and the tertiary substructure 1133 is a double-arrow-shaped structure; or, the primary substructure 1131 is an H-shaped structure, the secondary substructure 1132 is a concave structure, and the tertiary substructure 1133 is a concave structure, and so on, and examples are not given one by one here. For the convenience of explanation, in this embodiment, the primary substructure 1131, the secondary substructure 1132, and the tertiary substructure 1133 are all described by taking the H-shaped structure as an example.

[0053] In this embodiment, the central structure 113 is further fractalized on the basis of the secondary substructure 1132. The secondary substructure 1132 is connected to the tertiary substructure 1133, further increasing the extension path of the central structure 113, which is equivalent to increasing the length of the geometric space of the inductor part and the area of ​​spatial capacitance distribution, thereby enhancing the induced current generated by the outer frame 111. The induced current generated by the outer frame 111 is absorbed by the lumped resistor 112, thereby enhancing the electromagnetic energy loss, thereby improving the electromagnetic wave absorption rate of a specific frequency.

[0054] Optionally, in one possible implementation, see Figure 8 To understand, Figure 8 A schematic diagram of the structure of an embodiment of the absorbing structure provided in the embodiment of the present invention. The absorbing structure is a square structure, and the absorbing structure also includes a second structure 12, a third structure 13 and a fourth structure 14; the first structure 11 and the fourth structure 14 are centrally symmetrical about the center point of the conductor structure layer 1; the second structure 12 is a structure obtained by rotating 90 degrees with the center point of the first structure 11 as the center; the second structure and the third structure are centrally symmetrical about the center point of the conductor structure layer 1. In the first structure 11, the first-level substructure 1131 of the central structure 113 takes an H-shaped structure as an example, and in the second structure 12, the first-level substructure 1131 of the central structure 113 is an I-shaped structure. It should be noted that the four structures of the first structure 11, the second structure 12, the third structure 13 and the fourth structure 14 all include an outer frame 111 and a central structure 113, and the parameter values ​​of the parameters in the outer frame 111 and the central structure 113 are the same. The parameter values ​​corresponding to the parameters in the embodiment of the present application are explained by taking the first structure 11 as an example.

[0055] In this embodiment, the absorbing structure includes a first structure 11, a second structure 12, a third structure 13 and a fourth structure 14. The first structure 11 and the fourth structure 14 are respectively located at a diagonal position of the absorbing structure, and the second structure 12 and the third structure 13 are respectively located at another diagonal position of the absorbing structure. The second structure 12 and the third structure 13 are both structures obtained by rotating the first structure 11 by 90 degrees with the center point of the first structure 11 as the center, which can ensure that the incident electromagnetic wave can produce the characteristics of absorption response in different TE and TM modes (horizontal or vertical polarization of the electric field).

[0056] Optionally, the outer frame 111 may be circular, or the outer frame 111 may be square. In the embodiment of the present invention, the outer frame 111 is square for example, wherein when N is 4, the outer frame 111 includes 4 straight strip structures, each straight strip structure is a side of the outer frame 111, each lumped resistor 112 connects two adjacent strip structures, and each lumped resistor 112 is arranged at a corner of the outer frame 111. In this embodiment, considering the current distribution state of the conductor pattern, the current distribution is stronger at the top corner, therefore, the lumped resistor 112 is arranged at the corner of the outer frame 111, the loss of electromagnetic energy will also be greater, and the absorption rate of electromagnetic waves of a specific frequency will be increased.

[0057] Optionally, in an example not shown in the figure, N can also be 8, the outer frame portion 111 includes 8 straight strip structures, the number of lumped resistors 112 is also 8, each side of the outer frame portion 111 includes two straight strip structures, each lumped resistor 112 connects two adjacent strip structures, and 4 of the lumped resistors 112 are correspondingly arranged at the 4 corner positions of the outer frame portion 111, and each of the 4 lumped resistors 112 is correspondingly arranged between two strip structures on one side. In this embodiment, lumped resistors 112 are respectively arranged at the angular position and the side position of the outer frame portion 111, and the lumped resistors 112 are used to absorb the induced current generated by the outer frame portion 111 to increase the absorption rate of electromagnetic waves of a specific frequency.

[0058] The wave absorbing structure is described in the above embodiment. The parameters included in the wave absorbing structure and the corresponding parameter values ​​are described below.

[0059] Optional, see Figure 2 To understand, Figure 2 The figure is a side view of an embodiment of an absorbing structure provided in an embodiment of the present invention. The thickness of the conductor structure layer 1 (denoted by "t1"), the value range of t1 can be 0.016mm-0.020mm, and t1 can be any value in the range of 0.016mm-0.020mm. For example, t1 can be 0.016mm, 0.018mm, or 0.020mm.

[0060] The thickness of the dielectric substrate layer 2 (represented by "h") can be in the range of 5.0 mm to 8.0 mm, and h can be any value in the range of 5.0 mm to 8.0 mm. For example, h can be 5.0 mm, 6.5 mm or 8.0 mm. The dielectric substrate layer 2 is made of FR-4 dielectric material, with a dielectric constant of 4 or 4.5 and a tangent loss of 0.02; or a PET dielectric substrate, with a dielectric constant of 3.2 and a tangent loss of 0.02.

[0061] The thickness of the conductor reflective layer 3 (denoted by "t2") may be in the range of 0.016 mm to 0.020 mm, and t2 may be any value in the range of 0.016 mm to 0.020 mm. For example, t2 may be 0.016 mm, 0.018 mm, or 0.020 mm. The conductor reflective layer 3 may be made of copper.

[0062] Optional, see Figure 8 It is understood that the side length of the absorbing structure is 36mm-44mm; in this embodiment, half of the side length of the absorbing structure (represented by "p"), the value range of p is 18mm-22mm, p can be any value in the range of 18mm-22mm, for example, p18 can be 18mm, 20mm, or 22mm.

[0063] Optionally, the outer frame portion 111 is square, and the side length of the outer frame portion 111 (indicated by "l1"), the value range of l1 is 14mm-16mm, l1 can be any value in the range of 14mm-16mm, for example, l1 can be 14mm, 15mm and 16mm.

[0064] Optionally, the width of the outer frame 111 (denoted by "w1"), the value range of w1 is 0.5mm-1.5mm. The value range of w1 is 0.5mm-1.5mm, w1 can be any value in the range of 0.5mm-1.5mm, for example, w1 can be 0.5mm, 1.0mm or 1.5mm.

[0065] Optionally, the width of the waist of the primary substructure 1131 (denoted by "w2"), the value range of w2 is 0.1mm-0.7mm, w2 can be any value in the range of 0.1mm-0.7mm, for example, w2 can be 0.1mm, 0.4mm, 0.7mm. The length of the waist of the primary substructure 1131 (denoted by "l2"), the value range of l2 is 5mm-7mm, l2 can be any value in the range of 5mm-7mm, for example, l2 can be 5mm, 6mm, 7mm.

[0066] Optionally, the distance from the outer edge of the outer frame to the corresponding side of the absorbing structure (denoted by "g1"), the value range of g1 is 2mm-3mm, and the specific value of g1 is determined according to p and l1.

[0067] Optionally, taking the H-shape as an example, the length of the waist of the secondary substructure 1132 (indicated by "l3"), the value range of l3 is 2.5mm-3.5mm, and l3 can be any value in the range of 2.5mm-3.5mm, for example, l3 can be 2.5mm, 3.0mm or 3.5mm.

[0068] Optionally, taking the H-shape as an example, the length of the side of the tertiary substructure 1133 (indicated by "l4"), the value range of l4 is 1.0mm-2.0mm, and l4 can be any value in the range of 1.0mm-2.0mm, for example, l4 can be 1.0mm, 1.5mm or 2.0mm.

[0069] It should be noted that, in the embodiment of the present invention, the widths of the waists of the primary substructure 1131 , the secondary substructure 1132 , and the tertiary substructure 1133 may all be the same.

[0070] Optionally, in the first structure 11, the total resistance of the N lumped resistors 112 ranges from 12.5Ω to 50Ω, for example, the total resistance in the first structure 11 is 25Ω. The total resistance of the 4N lumped resistors 112 in the first structure 11, the second structure 12, the third structure 13, and the fourth structure 14 ranges from 50Ω to 200Ω. For example, the total resistance in the four structures is 100Ω.

[0071] In the embodiment of the present application, by designing the conductor pattern of the conductor structure layer 1 and the parameter values ​​corresponding to the parameters in the conductor pattern, electromagnetic waves of a specific frequency can be absorbed. For example, the wave absorbing structure can absorb the electromagnetic waves emitted by the operating frequencies of 2.45 GHz and 5.8 GHz of the dual-band WiFi, shielding the interference of WiFi signals for certain devices. Alternatively, electromagnetic waves of a specific frequency emitted by certain devices can be shielded to prevent these devices from interfering with WiFi signals. For example, the operating frequency of the induction cooker is 2.45 GHz, so the conductor structure can be made into an electromagnetic wave shielding material for the induction cooker to prevent interference with WiFi signals when the induction cooker is working.

[0072] In the embodiment of the present application, an absorbing material is also provided, which includes the above-mentioned multiple periodically arranged absorbing structures (the absorbing structure is described by an example including a first structure, a second structure, a third structure 13 and a fourth structure 14). A simulation experiment is conducted on the absorbing material, and a target absorbing material arranged in an infinite periodic array is established using simulation software. Electromagnetic waves are emitted by an excitation source, and the test frequency band is 0.5 GHz-6 GHz. The electromagnetic waves are incident on the target absorbing material, and the frequency band of the electromagnetic waves absorbed by the target and the corresponding absorption rate are tested.

[0073] The parameters in the above embodiment can be selected. The values ​​of some variables can be selected first. The relevant parameters are p, w1, w2, l1, l2, R0, h, e r By changing the values ​​of some of the parameters, the absorption characteristics of the corresponding absorbing materials will also change accordingly to meet certain special customized requirements.

[0074] For details, please refer to Fig. 9 As shown, Fig. 9 FIG. 1 is a schematic diagram of a frequency-reflectivity curve showing a change in the side length p of the absorbing structure according to an embodiment of the present invention. Fig. 9 As can be seen in the figure, the corresponding reflectivity curve change characteristics. For the convenience of explanation, the reflectivity curve corresponding to p = 18mm is the first reflectivity curve, the reflectivity curve corresponding to p = 20mm is the second reflectivity curve, and the reflectivity curve corresponding to p = 22mm is the third reflectivity curve. In the range of 18mm-22mm, as the length p increases, the resonant peak of the first reflectivity curve will shift toward high frequency, while the resonant peaks of the second and third reflectivity curves will move toward low frequency, that is, the entire resonant peak position will move toward the center frequency, and the resonance intensity will also increase, especially for the first and second resonant regions, when p = 22mm, a broadband absorption effect is formed, and the absorption intensity of -10dB covers 2.5GHz-4GHz. Therefore, by adjusting the length p, some low-frequency broadband application scenarios can be met.

[0075] See also Fig.10 As shown, Fig.10 FIG. 1 is a curve diagram showing the change in frequency-reflectivity when the width w1 of the outer frame portion changes in the embodiment of the present invention. Fig.10It can be seen that within the range of 0.5mm-1.5mm, as w1 increases, the resonance peak offset of the corresponding reflectivity curve is small. When w1=1.5mm, the absorption characteristics of the first resonance peak are the strongest. Therefore, it is particularly effective for absorbing 2.45GHz WiFi signals, and the absorption intensity can reach -50dB. When w1=1.0mm, the absorption intensity of electromagnetic waves at 2.45GHz can reach -20dB, the absorption intensity of electromagnetic waves at 3.8GHz can reach -11dB, and the absorption intensity of electromagnetic waves at 5.8GHz can reach -19dB. When w1=0.5mm, the absorption intensity of electromagnetic waves at 2.5GHz can reach -12dB, the absorption intensity of electromagnetic waves at 3.8GHz can reach -15dB, and the absorption intensity of electromagnetic waves at 5.8GHz can reach -20dB.

[0076] See also Fig.11 As shown, Fig.11 FIG. 1 is a curve diagram showing the change in frequency-reflectivity when the width w2 of the primary substructure changes in the embodiment of the present invention. Fig.11 It can be seen that in the range of 0.1mm-0.7mm, as w2 increases, the resonant peak of the corresponding reflectivity curve will shift toward high frequency. Therefore, by adjusting the width of the primary substructure (the width of the secondary substructure and the tertiary substructure is the same as the width of the primary substructure), the absorption frequency position can be effectively adjusted, which provides a very clear parameter optimization direction for designing absorbing materials with specific working frequencies. For example, when w2=0.4, the absorption intensity of electromagnetic waves at 2.45GHz can reach -20dB, the absorption intensity of electromagnetic waves at 5.8GHz can reach -18dB, and the absorption intensity of electromagnetic waves at 3.8GHz can reach -11dB. When w2=0.1, the absorption intensity of electromagnetic waves at 2.25GHz can reach -30dB, and the absorption intensity of electromagnetic waves at 5.7GHz can reach -18dB.

[0077] See also Fig.12 As shown, Fig.12 is a curve diagram showing the change in frequency-reflectivity when the side length l1 of the outer frame changes. Fig.12 It can be seen that within the range of 14mm-16mm, as l1 increases, the low-frequency resonance peak will shift to low frequency, and the high-frequency resonance peak will move to high frequency. When l1 = 16mm, the absorption intensity of electromagnetic waves at 2.45GHz can reach -20dB, and the absorption intensity of electromagnetic waves at 5.8GHz can reach -18dB.

[0078] See also Fig.13 As shown, Fig.13Schematic diagram of the curve of the corresponding frequency-reflectivity change when the length l2 of the waist of the primary substructure changes. Fig.13 It can be seen that within the range of 5mm-7mm, as l2 increases, the low-frequency resonance peak will shift toward low frequency, but the shift of the high-frequency resonance peak position does not have a monotonic change pattern. When l2 = 6mm, the absorption intensity of electromagnetic waves at 2.45GHz can reach -20dB, and the absorption intensity of electromagnetic waves at 5.8GHz can reach -18dB. When l2 = 5mm, the absorption intensity of electromagnetic waves at 4.5GHz can reach -17dB. When l2 = 7mm, the absorption intensity of electromagnetic waves at 2.1GHz can reach -33dB, and the absorption intensity of electromagnetic waves at 5.2GHz can reach -13dB.

[0079] See also Fig.14 As shown, Fig.14 It is a curve diagram showing the corresponding frequency-reflectivity change when the lumped resistance R0 changes. Fig.14 It can be seen that within the range of 50Ω-200Ω, as R0 increases, the position of the resonance peak of the corresponding reflectivity curve and the absorption intensity change significantly. In design, resistance R0 is a key parameter for adjusting the absorption effect of a specific frequency. When R0 = 100Ω, the absorption intensity of electromagnetic waves at 2.48GHz can reach -20dB, and the absorption intensity of electromagnetic waves at 5.8GHz can reach -20dB. When R0 = 50Ω, the absorption intensity of electromagnetic waves at 2GHz can reach -20dB, and the absorption intensity of electromagnetic waves at 5.8GHz can reach -17dB. When R0 = 200Ω, the absorption intensity of electromagnetic waves at 2.48GHz can reach -17dB, and the absorption intensity of electromagnetic waves at 3.5GHz can reach -13dB.

[0080] See also Fig.15 As shown, Fig.15 It is a schematic diagram of the frequency-reflectivity curve when the thickness h of the dielectric substrate layer changes. Fig.15 It can be seen that within the range of 5mm-8mm, as h increases, the resonance peak of the corresponding reflectivity curve will shift toward low frequency, and the absorption intensity corresponding to the resonance peak will also change significantly. When h = 5.0mm, the absorption intensity of electromagnetic waves at 2.5GHz can reach -21dB, and the absorption intensity of electromagnetic waves at 4GHz can reach -15dB. When h = 6.5mm, the absorption intensity of electromagnetic waves at 2.5GHz can reach -20dB, and the absorption intensity of electromagnetic waves at 5.8GHz can reach -20dB. When h = 8.0mm, the absorption intensity of electromagnetic waves at 2.0GHz can reach -17dB, and the absorption intensity of electromagnetic waves at 5.5GHz can reach -12dB.

[0081] See also Fig.16 As shown, Fig.16 is the dielectric constant of the dielectric substrate layer e r When changes occur, the corresponding frequency-reflectivity curve diagram is shown. Fig.15 It can be seen that in the range of 3.2-4.5, as e r As the dielectric constant increases, the resonant peak of the corresponding reflectivity curve will shift toward low frequency. The adjustment of this parameter broadens the range of material selection. For example, if the dielectric constant is 3.2, PET-type flexible materials can be selected, and PET materials also have transparent properties.

[0082] See also Fig.17 As shown, Fig.17 The figure is a schematic diagram of the corresponding frequency-reflectivity change curve when the electromagnetic wave is incident on the surface of the absorbing material at different angles in the TE mode. Fig.17 It can be seen that within the range of 15 degrees to 45 degrees, as theta increases, the resonance peak position and intensity of the corresponding reflectivity curve do not show a more obvious shift characteristic, indicating that the absorbing material can maintain a good absorption effect even when used at a relatively large angle.

[0083] See also Fig.18 As shown, Fig.18 The figure is a schematic diagram of the corresponding frequency-reflectivity curve when the electromagnetic wave is incident on the surface of the absorbing material at different angles in the TM mode. Fig.18 It can be seen that within the range of 15 degrees to 45 degrees, as theta increases, the resonance peak position and intensity of the corresponding reflectivity curve do not show a more obvious shift characteristic, indicating that the absorbing material can maintain a good absorption effect even when used at a relatively large angle.

[0084] Combination Fig.17 and Fig.18 It can be seen from the curve change characteristics that the absorbing material designed in the present invention not only has a good absorption effect at a large angle, but also exhibits very good absorption performance for incident electromagnetic waves with different polarizations.

[0085] It should be noted that Figure 2 and Figure 8 When other relevant geometric parameters indicated in are changed, the corresponding absorption curve will also shift accordingly, and the bandwidth will also change accordingly, which will not be elaborated here.

[0086] By adjusting the specific parameter values ​​of the above parameters, the wave absorbing structure in the embodiment of the present invention can absorb electromagnetic waves of a specific frequency.

[0087] In summary, in the above embodiments, the relevant parameters and their exemplary values ​​can be: p = 18mm; l1 = 16mm; l2 = 6mm; l3 = 3mm; l4 = 1.5mm; h = 6.5mm; t1 = 0.018mm; t2 = 0.018mm; g1 = 1mm; w1 = 1mm; w2 = 0.4mm; R0 = 100Ω. The dielectric constant of the dielectric material selected in the design is 4.5, and the tangent loss is 0.02. In the embodiment of the present application, the wave absorption effect of about -20dB at 2.45GHz, about -11dB at 3.8GHz, and about -19dB at 5.8GHz is achieved.

[0088] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A wave absorbing structure, characterized in that: It comprises a dielectric substrate layer, a conductor structure layer arranged on one surface of the dielectric substrate layer, and a conductor reflection layer arranged on the other surface of the dielectric substrate layer; the conductor structure layer comprises a first structure, the first structure comprises an outer frame and a central structure located in the outer frame; the outer frame comprises N strip structures and N lumped resistors; each of the N lumped resistors is connected between every two adjacent strip structures in the N strip structures; the central structure comprises a primary substructure and a secondary substructure; both the primary substructure and the secondary substructure are axisymmetric structures; the primary substructure comprises two sides and a waist connecting the two sides, each of the sides of the primary substructure has at least two ends; the secondary substructure comprises two sides and a waist connecting the two sides, each of the sides of the secondary substructure has at least one end; each of the ends included in the primary substructure is connected to the waist of the secondary substructure, and the size of the primary substructure is larger than that of the secondary substructure; Wherein, the primary substructure and the secondary substructure are both H-shaped structures, the central structure further includes a tertiary substructure, each of the ends of the secondary substructure is connected to the tertiary substructure, the tertiary substructure is an axisymmetric structure, and the tertiary substructure includes two side portions and a waist portion connecting the two side portions, and each of the side portions of the tertiary substructure has at least one end; the size of the secondary substructure is larger than that of the tertiary substructure; The absorbing structure is a square structure, and the absorbing structure further includes a second structure, a third structure and a fourth structure; the first structure and the fourth structure are centrally symmetrical about the center point of the conductor structure layer; the second structure is a structure obtained by rotating 90 degrees with the center point of the first structure as the center; the second structure and the third structure are centrally symmetrical about the center point of the conductor structure layer; Wherein, the tertiary substructure is an H-shaped structure or a concave structure.

2. The wave absorbing structure according to claim 1, characterized in that: The side length of the wave absorbing structure is 18mm-22mm; the outer frame is square, and the side length of the outer frame ranges from 14mm to 16mm; the width of the outer frame ranges from 0.5mm to 1.5mm.

3. The wave absorbing structure according to claim 1, characterized in that: The outer frame is square, N is 4, each lumped resistor connects two adjacent strip structures, and each lumped resistor is arranged at a corner position of the outer frame.

4. The wave absorbing structure according to claim 1, characterized in that: The primary substructure includes a first side portion and a second side portion parallel to each other, and a waist portion perpendicular to the first side portion and the second side portion; the width of the waist portion ranges from 0.1 mm to 0.7 mm; the length of the waist portion ranges from 5 mm to 7 mm.

5. The wave absorbing structure according to claim 1, characterized in that: The total resistance of the N lumped resistors ranges from 12.5Ω to 50Ω.

6. The wave absorbing structure according to claim 1, characterized in that: The thickness of the dielectric substrate layer ranges from 5 mm to 8 mm.

7. The wave absorbing structure according to claim 1, characterized in that: The dielectric constant of the dielectric substrate layer is 3.2-4.5.

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