A wave absorbing unit and a wave absorbing structure

Abstract

The present invention provides an absorbing unit and an absorbing structure, which relate to the technical field of electromagnetic wave absorbing materials. The absorbing unit includes a base, a first absorbing body and a plurality of second absorbing bodies. The base is prism-shaped. The first absorbing body includes a plurality of absorbing parts, and the plurality of absorbing parts are arranged on the base; the plurality of absorbing parts are arranged along a circular path, and the horizontal cross-section of the first absorbing body is in the shape of a polygonal star. The absorbing part is in the shape of a cone. The second absorbing body is arranged on the base, and a second absorbing body is arranged between any two adjacent absorbing parts; the second absorbing body is in the shape of a pyramid, and the second absorbing body has a side surface coplanar with the side surface of the base. The height of the absorbing part is greater than the height of the second absorbing body. The absorbing structure provided by the present invention adopts the above-mentioned absorbing unit. The absorbing unit and absorbing structure provided by the present invention can improve the technical problem in the prior art that it is difficult to take into account the application scenarios of multiple angles and wide frequency bands.

Description

Technical Field

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

[0002] Electromagnetic wave absorbing materials, also known as absorbing materials, are an important component of the anechoic chamber and a key material for reducing electromagnetic wave scattering in the anechoic chamber. Usually we only care about the performance of absorbing materials when electromagnetic waves are incident vertically, and pay less attention to the cases of incidence at other angles. For some special application scenarios, absorbing materials receive electromagnetic wave radiation from all directions, even at large angles of 50-70°. However, the absorption performance of conventional pyramidal absorbing materials decreases rapidly with the increase of the electromagnetic wave incident angle, and the lower the frequency band used, the more obvious the performance degradation.

[0003] In view of the wide-angle application of absorbing materials, some new structural design schemes have been proposed in the relevant technologies, mainly including the typical structures of splicing various polyhedral cones into different wedge-shaped cones (such as JP2015164230A); designing multiple small wedge-shaped cones on the cone surface of a large wedge-shaped cone (such as JPA 1984129494); and designing small cones on a large wedge-shaped cone (such as JPH08274490A). However, although the above structures can show good absorption performance at certain oblique incident angles or certain frequency bands, it is difficult to take into account the application scenarios of multiple angles and wide frequency bands. Summary of the invention

[0004] The technical problem solved by the present invention is how to improve the technical problem that it is difficult to take into account application scenarios with multiple angles and wide frequency bands in the prior art.

[0005] The embodiments of the present invention can be implemented as follows:

[0006] The present invention provides a wave absorbing unit, comprising:

[0007] A base, wherein the base is in a prism shape;

[0008] The first absorbing body comprises a plurality of absorbing parts, wherein the plurality of absorbing parts are arranged on the base; the plurality of absorbing parts are arranged along a circumferential path, and the horizontal cross-section of the first absorbing body is in the shape of a polygonal star; the horizontal cross-sectional area of ​​the absorbing part gradually decreases from one end close to the base to one end far from the base, so that the absorbing part is in the shape of a cone;

[0009] A plurality of second wave absorbing bodies are arranged on the base, and one second wave absorbing body is arranged between any two adjacent wave absorbing parts; the second wave absorbing bodies are pyramid-shaped, and the second wave absorbing bodies have side surfaces coplanar with the side surfaces of the base;

[0010] A height of the wave absorbing portion relative to the base is greater than a height of the second wave absorbing body relative to the base.

[0011] The beneficial effects of the wave absorbing unit provided by the present invention compared with the prior art include:

[0012] When the absorbing unit is applied to the absorbing structure, the absorbing structure is composed of a plurality of periodic absorbing units. When low-frequency electromagnetic waves are directly incident, the first absorbing body provides the main absorbing function due to the large wavelength of the electromagnetic waves. When high-frequency electromagnetic waves are directly incident, the second absorbing body fills the gap between the first absorbing bodies due to the small wavelength of the electromagnetic waves, weakening the reflection of the electromagnetic waves when incident on the base, and assisting in increasing the absorption of high-frequency electromagnetic waves. In addition, when the electromagnetic waves are obliquely incident, the second absorbing body increases the number of reflections of the electromagnetic waves between the first absorbing body and the second absorbing body. At the same time, in the oblique incident direction, the shapes of the first absorbing body and the second absorbing body are both cone-like impedance gradient structures, which are conducive to the absorption of oblique incident electromagnetic waves. Based on this, the absorbing unit can improve the technical problems in the prior art that it is difficult to take into account multi-angle and wide-band application scenarios.

[0013] Optionally, the first absorbing body and the second absorbing body are distributed over the entire upper surface of the base.

[0014] Optionally, the number of edges of the base is equal to the number of the wave absorbing parts; the number of the second wave absorbing bodies is equal to the number of the wave absorbing parts.

[0015] Optionally, the edge of the absorbing part away from the center of the circumferential path is connected to the edge of the base; the edge of the second absorbing body close to the absorbing part is connected to the intersection line between two adjacent absorbing parts.

[0016] Optionally, the first absorbing body, the second absorbing body and the base are integrally formed.

[0017] Optionally, the second wave absorbing body is a triangular pyramid.

[0018] Optionally, the number of the wave absorbing parts is four, so that the cross section of the first wave absorbing body is in the shape of a four-pointed star;

[0019] Alternatively, the number of the wave absorbing parts is six, so that the cross section of the first wave absorbing body is in the shape of a hexagonal star.

[0020] Optionally, when the side of the second absorbing body away from the absorbing part is coplanar with the side of the base, the second absorbing body is tilted so that the edge of the second absorbing body close to the absorbing part is tilted relative to the vertical plane.

[0021] A wave absorbing structure comprises a plurality of the above-mentioned wave absorbing units, wherein the plurality of the wave absorbing units are spliced ​​with each other; in any two adjacent wave absorbing units, two of the second wave absorbing bodies are spliced ​​to form a pyramid.

[0022] A wave absorbing structure comprises a plurality of the above-mentioned wave absorbing units, wherein the plurality of the wave absorbing units are spliced ​​with each other; in any two adjacent wave absorbing units, the two spliced ​​second wave absorbing bodies are arranged in a staggered splicing manner.

[0023] The beneficial effects of the wave absorbing structure provided by the present invention relative to the prior art are the same as the beneficial effects of the wave absorbing unit provided above relative to the prior art, and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 , 3 , 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, and 27 are schematic diagrams of structures of various absorbing units provided in the first embodiment of the present application respectively;

[0026] Fig.29 , 31 3 and 33 are schematic diagrams of different arrangements of the absorbing units provided in the first embodiment of the present application;

[0027] Figure 2 , 4 , 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, and 34 are reflectivity curves obtained by simulation calculation according to the corresponding absorbing units or absorbing unit component structures.

[0028] Icon: 10 - absorbing unit; 100 - base; 200 - first absorbing body; 210 - absorbing portion; 211 - first side; 212 - second side; 213 - first angle; 214 - second angle; 300 - second absorbing body. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0030] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0032] In the description of the present invention, it should be noted that if the terms "upper", "lower", "inside", "outside", etc. appear to indicate an orientation or position relationship, they are based on the orientation or position relationship shown in the accompanying drawings, or are the orientation or position relationship in which the product of the invention is usually placed when used. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0033] In addition, the terms “first”, “second”, etc., if used, are merely used to distinguish between the descriptions and should not be understood as indicating or implying relative importance.

[0034] It should be noted that, in the absence of conflict, the features in the embodiments of the present invention may be combined with each other.

[0035] First embodiment

[0036] See also Figure 1 In this embodiment, an absorbing unit 10 is provided. In application scenarios such as an anechoic chamber, the absorbing unit 10 can form a structure for absorbing electromagnetic waves. The absorbing unit 10 provided in this embodiment can improve the technical problem that it is difficult to take into account multi-angle and wide-band application scenarios in the prior art.

[0037] In this embodiment, the absorbing unit 10 includes a base 100, a first absorbing body 200 and a plurality of second absorbing bodies 300. The base 100 is prism-shaped; optionally, in this embodiment, the base 100 is a regular prism-shaped. The first absorbing body 200 includes a plurality of absorbing parts 210, and the plurality of absorbing parts 210 are arranged on the base 100; the plurality of absorbing parts 210 are arranged along a circumferential path, and the cross section of the first absorbing body 200 is a polygonal star. Among them, the area of ​​the horizontal cross section of the absorbing part 210 gradually decreases from the side close to the base 100 to the side away from the base 100, so that the absorbing part 210 is conical; based on this, the area of ​​the horizontal cross section of the first absorbing body 200 gradually decreases from the side close to the base 100 to the side away from the base 100. The second absorbing body 300 is disposed on the base, and one second absorbing body 300 is disposed between any two adjacent absorbing parts 210; the second absorbing body 300 is pyramidal, and the second absorbing body 300 has a side surface coplanar with the side surface of the base 100. In this embodiment, the first absorbing body 200, the second absorbing body 300 and the base 100 are integrally formed.

[0038] Among them, since the area of ​​the horizontal cross-section of the first absorbing body 200 gradually decreases from the side close to the base 100 to the side far from the base 100, and the cross-section of the first absorbing body 200 is a polygonal star, the overall structure of the first absorbing body 200 can be called a polygonal star cone. For example, when the horizontal cross-section of the first absorbing body 200 is a four-pointed star, the first absorbing body 200 is called a four-pointed star cone; for another example, when the horizontal cross-section of the first absorbing body 200 is a hexagonal star, the first absorbing body 200 is called a hexagonal star cone.

[0039] In the absorbing unit 10, the absorbing part 210 and the second absorbing body 300 are arranged alternately on the base 100. When the absorbing unit 10 is applied to the absorbing structure, the absorbing structure is formed by a plurality of periodic absorbing units 10. When low-frequency (e.g., below 1 GHz) electromagnetic waves are directly incident, the first absorbing body 200 provides the main absorbing function due to the large wavelength of the electromagnetic waves; when high-frequency (e.g., above 1 GHz) electromagnetic waves are directly incident, the second absorbing body 300 can fill the gap between the first absorbing bodies 200 due to the small wavelength of the electromagnetic waves, thereby reducing the reflection of the electromagnetic waves when they are incident on the base 100 and assisting in increasing the absorption of the electromagnetic waves. In this way, the absorbing structure can take into account both high and low frequency use, and expand the width of the frequency band used. In addition, when the electromagnetic wave is incident at an oblique angle (other incident angles than 0°), the second absorbing body 300 increases the number of reflections of the electromagnetic wave between the first absorbing body 200 and the second absorbing body 300. At the same time, in the oblique incident direction, the shapes of the first absorbing body 200 and the second absorbing body 300 are both cone-like impedance gradient structures, which are conducive to the absorption of oblique incident electromagnetic waves. Based on this, the absorbing unit 10 can improve the technical problem of the prior art that it is difficult to take into account multi-angle and wide-band application scenarios.

[0040] The structure of the first absorbing body 200 is described by taking the cross section of the first absorbing body 200 as a four-pointed star as an example. The first absorbing body 200 includes four absorbing parts 210, and the plurality of absorbing parts 210 are connected to form the first absorbing body 200; it is worth noting that, in general, in order to facilitate the processing of the first absorbing body 200 and to ensure that the absorbing effect generated around the first absorbing body 200 is equivalent, the structures of the plurality of absorbing parts 210 are the same. Fig.19 , Fig.19 is a top view (where Fig.19For example, the direction perpendicular to the paper surface is the vertical direction, and the direction parallel to the paper surface is the horizontal direction). The outer contour of the cross section of each absorbing portion 210 in the horizontal plane forms a quadrilateral, and the quadrilateral can be divided into two first sides 211 and two second sides 212. The two first sides 211 are connected and form a first angle 213, and the two second sides 212 are connected and form a second angle 214. The first angle 213 and the second angle 214 are relative angles in the quadrilateral. In the cross section of the first absorbing body 200 along the horizontal plane, the second sides 212 of adjacent absorbing portions 210 overlap, and each second angle 214 is a right angle. In addition, each absorbing part 210 has four side surfaces, two of which are vertical planes, and the two vertical planes form two second edges 212 in the cross section of the first absorbing body 200 along the horizontal plane; correspondingly, the other two side surfaces are inclined planes, and the two inclined planes form two first edges 211 in the cross section of the first absorbing body 200 along the horizontal plane. Thus, the four absorbing parts 210 together form the first absorbing body 200.

[0041] It is worth noting that in the present embodiment, the plurality of absorbing parts 210 in the first absorbing body 200 are formed by an integrated molding process, and the first absorbing body 200 is divided into the plurality of absorbing parts 210 only for the convenience of describing the specific shape of the first absorbing body 200 .

[0042] Of course, in other embodiments of the present application, the number of the absorbing parts 210 in the first absorbing body 200 may also be other values. For example, the first absorbing body 200 has six absorbing parts 210, and in this case, the second angle 214 is 60°. Of course, the number of the absorbing parts 210 in the first absorbing body 200 may also be other values, which will not be described in detail here.

[0043] In this embodiment, the first absorbing body 200 and the second absorbing body 300 are spread all over the upper surface of the base 100. The first absorbing body 200 is formed by a plurality of absorbing parts 210. When the plurality of absorbing parts 210 are disposed on the upper surface of the base 100, a partial area of ​​the upper surface of the base 100 is exposed between two adjacent absorbing parts 210, and the second absorbing body 300 is disposed in the exposed area, and the second absorbing body 300 is spread all over the exposed area, so that the upper surface of the base 100 is spread all over by the first absorbing body 200 and the second absorbing body 300.

[0044] Further, in the present embodiment, the number of edges of the base 100 is equal to the number of the absorbing parts 210; thus, the arrangement of the first absorbing body 200 on the base 100 can be facilitated, and the overall design and processing difficulty of the absorbing unit 10 can be simplified. In addition, the number of the second absorbing bodies 300 is equal to the number of the absorbing parts 210, so that the first absorbing body 200 and the second absorbing body 300 are closely arranged on the base 100. For example, in the case where there are four absorbing parts 210 in the first absorbing body 200, the number of the second absorbing bodies 300 is four, and one second absorbing body 300 is arranged between every two adjacent absorbing parts 210. For another example, in the case where there are six absorbing parts 210 in the first absorbing body 200, the number of the second absorbing bodies 300 is six, and one second absorbing body 300 is arranged between every two adjacent absorbing parts 210.

[0045] It should be understood that setting the number of the second absorbing bodies 300 to be equal to the number of the absorbing parts 210 is a preferred embodiment of the present application.

[0046] In addition, in this embodiment, the edge of the absorbing part 210 away from the center of the circumferential path is connected to the edge of the base 100; the edge of the second absorbing body 300 close to the absorbing part 210 is connected to the intersection line between two adjacent absorbing parts 210.

[0047] It is worth noting that in the absorbing unit 10, low-frequency electromagnetic waves are mainly absorbed by the first absorbing body 200, and high-frequency electromagnetic waves are absorbed by the first absorbing body 200 and the second absorbing body 300. According to the working principle of the absorbing material, in order to achieve effective absorption of low frequencies (at least greater than 1 / 4 wavelength), the size of the first absorbing body 200 needs to be designed to be larger (compared to the second absorbing body 300), and its height relative to the base 100 is also higher (compared to the second absorbing body 300). On the contrary, in the high-frequency band, the size of the second absorbing body 300 is smaller and its height relative to the base 100 is lower. In addition, from the overall perspective of the absorbing unit 10, the first absorbing body 200 and the second absorbing body 300 with high and low displacements form a secondary structure, which increases the reflection attenuation of electromagnetic waves between the first and second absorbing bodies.

[0048] In this embodiment, the second absorbing body 300 is a triangular pyramid. Further, in the embodiment of the present application, a side surface of the second absorbing body 300 coplanar with the side surface of the base 100 is an isosceles triangle (the side close to the base 100 is used as the bottom side), so the second absorbing body 300 can be regarded as a cone structure formed by extending vertically upward. In some embodiments of the present application, while keeping the side surface of the second absorbing body 300 away from the absorbing part 210 coplanar with the side surface of the base 100, the second absorbing body 300 is tilted so that the edge of the second absorbing body 300 close to the absorbing part 210 is tilted relative to the vertical plane. At this time, the side surface of the second absorbing body 300 coplanar with the side surface of the base 100 is not an isosceles triangle (the side close to the base 100 is used as the bottom side), so the second absorbing body 300 can be regarded as a cone structure formed by extending obliquely upward.

[0049] It should be noted that, based on the surface coplanar with the side surface of the second absorbing body 300 and the base 100, the second absorbing body 300 has an edge on the side away from the side surface, and the edge is connected to the intersection line of two adjacent absorbing parts 210. Figure 1 ), the edge, the intersection line of the two absorbing parts 210 connected to the edge, and the central axis of the first absorbing body 200 are located in the same plane; and in the case where the second absorbing body 300 is inclined (such as Fig.25 ), the edge is offset away from the above plane, thus forming a second absorbing body 300 which is inclined.

[0050] Based on the absorbing unit 10 provided above, the inventors conducted simulation calculations for several different absorbing units 10 to calculate the reflectivity of each absorbing unit 10 model, as follows (it should be noted that when the number of absorbing parts 210 is six, the horizontal cross-section of the first absorbing body 200 is a hexagonal star. For the convenience of description, the shape of the first absorbing body 200 is a hexagonal star cone. Correspondingly, when the number of absorbing parts 210 is four, the shape of the first absorbing body 200 is a four-pointed star cone):

[0051] First, please refer to Figure 1 and Figure 2 In the absorbing unit 10, the first absorbing body 200 is in the shape of a hexagonal star cone, which means that the first absorbing body 200 has six absorbing parts 210, and correspondingly, the number of the second absorbing bodies 300 is six. Figure 2 It represents the reflectivity curve generated by electromagnetic waves incident at different angles obtained by simulation calculation of the wave absorbing unit 10 model. Figure 2In the graph, TE indicates that the incident electromagnetic wave is processed by TE polarization, and TM indicates that the incident electromagnetic wave is processed by TM polarization. The ordinate indicates the reflectivity of the absorbing material to the incident electromagnetic wave, in dB (decibel), and the abscissa indicates the frequency of the incident electromagnetic wave, in GHz. In addition, the multiple angles below the graph indicate the incident angles of the electromagnetic wave.

[0052] Second, please refer to Figures 3 to 10 ,in, Figure 3 , Figure 5 , Figure 7 and Fig. 9 In the absorbing unit 10, the first absorbing body 200 is a four-pointed star cone, which means that the first absorbing body 200 has four absorbing parts 210, and correspondingly, the number of the second absorbing bodies 300 is four. Figure 3 , Figure 5 , Figure 7 and Fig. 9 The difference between the absorbing units 10 in the embodiment is that the heights of the second absorbing units 10 are 100 mm, 150 mm, 200 mm and 250 mm respectively. Figure 4 Indicates the corresponding Figure 3 A reflectivity curve diagram of electromagnetic waves incident at different angles obtained by simulation calculation of the middle absorbing unit 10 model; Figure 6 Indicates the corresponding Figure 5 A reflectivity curve diagram of electromagnetic waves incident at different angles obtained by simulation calculation of the middle absorbing unit 10 model; Figure 8 Indicates the corresponding Figure 7 A reflectivity curve diagram of electromagnetic waves incident at different angles obtained by simulation calculation of the middle absorbing unit 10 model;

[0053] Fig.10 Indicates the corresponding Fig. 9 The reflectivity curves of electromagnetic waves incident at different angles are obtained by simulation calculation of the absorber unit 10 model. It is worth noting that Figure 4 , Figure 6 , Figure 8 and Fig.10 The small cone in the figure refers to the second absorbing body 300 .

[0054] Third, please refer to Figures 11 to 16 ,in, Fig.11 , Fig.13 and Fig.15 In the absorbing unit 10, the first absorbing body 200 is a four-pointed star cone, which means that the first absorbing body 200 has four absorbing parts 210, and correspondingly, the number of the second absorbing bodies 300 is four. Fig.11 , Fig.13 and Fig.15The difference between the absorbing unit 10 in the embodiment is that the width of the base 100 is 250 mm, 300 mm and 400 mm respectively (the width is Fig.11 The A in the middle indicates that Fig.13 B indicates that Fig.15 Correspondingly, Fig.12 Indicates the corresponding Fig.11 A reflectivity curve diagram of electromagnetic waves incident at different angles obtained by simulation calculation of the middle absorbing unit 10 model; Fig.14 Indicates the corresponding Fig.13 A reflectivity curve diagram of electromagnetic waves incident at different angles obtained by simulation calculation of the middle absorbing unit 10 model; Fig.16 Indicates the corresponding Fig.15 The reflectivity curves generated by electromagnetic waves incident at different angles are obtained by simulation calculation of the middle absorbing unit 10 model.

[0055] It is worth noting that when the height of the first absorbing body 200 remains unchanged and the width of the base 100 changes, the vertex angles of the first absorbing body 200 and the second absorbing body 300 will increase as the width of the base 100 increases, which can also be regarded as the increase in the vertex angle of the absorbing part 210, which in turn leads to an increase in the vertex angle of the first absorbing body 200.

[0056] from Figure 4 , Figure 6 , Figure 8 as well as Fig.10 It can be seen that, when the width of the base 100 is 300mm as a reference, the incident electromagnetic wave is processed by TE polarization, and the incident angle of the electromagnetic wave is in the range of 0°-30°. The width of the base 100 is reduced (the width of the base 100 is reduced to 250mm), and the reflectivity performance between 0.8GHz-2GHz increases by about 5dB; the width of the base 100 is increased (the width of the base 100 is increased to 400mm), and the reflectivity performance between 0.7GHz-2GHz decreases by about 5dB-10dB. When the incident angle of the electromagnetic wave is in the range of 40°-70°, the change in the width of the base 100 has little effect on the reflectivity, which will not be repeated here. In addition, the incident electromagnetic wave adopts TM polarization processing, and the incident angle of the electromagnetic wave is between 0°-20°, the width of the base 100 is reduced, and the reflectivity performance at 0.8GHz-2GHz increases by about 5dB; the width of the base 100 is increased, and the reflectivity performance at 0.7GHz-2GHz decreases by about 5dB-10dB. When the incident angle is between 50°-70°, the overall performance is improved to a certain extent at 1.2GHz-2GHz.

[0057] Fourth, please refer to Figures 17 to 24 ,in, Fig.17 , Fig.19 , Fig.21 and Fig.23 In the absorbing unit 10, the first absorbing body 200 is a four-pointed star cone, which means that the first absorbing body 200 has four absorbing parts 210, and correspondingly, the number of the second absorbing bodies 300 is four. Fig.17 , Fig.19 , Fig.21 and Fig.23 The difference between the absorbing unit 10 in the embodiment is that the values ​​of the first angle 213 are 15°, 30°, 45° and 60° respectively; correspondingly, Fig.18 Indicates the corresponding Fig.17 A reflectivity curve diagram of electromagnetic waves incident at different angles obtained by simulation calculation of the middle absorbing unit 10 model; Fig. 20 Indicates the corresponding Fig.19 A reflectivity curve diagram of electromagnetic waves incident at different angles obtained by simulation calculation of the middle absorbing unit 10 model; Fig. 22 Indicates the corresponding Fig.21 A reflectivity curve diagram of electromagnetic waves incident at different angles obtained by simulation calculation of the middle absorbing unit 10 model; Fig.24 Indicates the corresponding Fig.23 The reflectivity curves generated by electromagnetic waves incident at different angles are obtained by simulation calculation of the middle absorbing unit 10 model.

[0058] It is worth noting that when the first angle 213 of the absorbing portion 210 increases, the overall thickness of the second absorbing body 300 becomes thinner, which can also be regarded as that the cone angle of the second absorbing body 300 close to the center of the first absorbing body 200 becomes larger, and the two cone angles formed by the side surfaces of the second absorbing body 300 coplanar with the base 100 become smaller.

[0059] from Fig.18 , Fig. 20 , Fig. 22 as well as Fig.24It can be seen that when the first angle 213 becomes smaller, the cone angle of the first absorbing body 200 becomes sharper; correspondingly, the two cone angles formed by the side surfaces of the second absorbing body 300 coplanar with the base 100 become larger, which can be regarded as the size of the second absorbing body 300 becomes blunter. When the incident angle of the electromagnetic wave is 0°-20°, the absorbing performance of the absorbing unit 10 is enhanced as the first angle 213 increases from 0GHz to 1.7GHz (regardless of whether the electromagnetic wave is TE polarized or TM polarized), but starting from about 1.7GHz, the smaller the first angle 213, the better the absorbing effect. When the incident angle of the electromagnetic wave is 30°-50°, in the range of 0GHz-2GHz, when the electromagnetic wave is TE polarized, as the first angle 213 increases, the absorbing performance is improved; in the range of 1GHz-2GHz, when the electromagnetic wave is TM polarized, the absorbing performance of the absorbing unit 10 is better than the absorbing unit 10 when the first angle 213 is larger when the first angle 213 is smaller. When the incident angle of the electromagnetic wave is in the range of 60°-70°, regardless of whether the electromagnetic wave is TE polarized or TM polarized, as the first angle 213 increases, the absorbing performance of the absorbing unit 10 decreases. In general, when the first angle 213 is larger, it can be ensured that the absorbing unit 10 has a better absorbing performance when the electromagnetic wave is incident at a small angle; and when the first angle 213 is smaller, it can be ensured that the absorbing unit 10 has a better absorbing performance when the electromagnetic wave is obliquely incident at a large angle.

[0060] Fifth, please refer to Figure 25 to Figure 28 ,in, Fig.25 and Fig. 27 In the absorbing unit 10, the first absorbing bodies 200 are all in the shape of a four-pointed star cone, which means that the first absorbing body 200 has four absorbing parts 210, and correspondingly, the number of the second absorbing bodies 300 is four. Fig.25 The second wave absorbing body 300 is offset in a clockwise direction to form an inclined triangular pyramid; and Fig. 27 The second wave absorbing body 300 in the embodiment is offset in the counterclockwise direction to form an inclined triangular cone; correspondingly, Fig.26 Indicates the corresponding Fig.25 A reflectivity curve diagram of electromagnetic waves incident at different angles obtained by simulation calculation of the middle absorbing unit 10 model; Fig.28 Indicates the corresponding Fig. 27 The reflectivity curves generated by electromagnetic waves incident at different angles are obtained by simulation calculation of the middle absorbing unit 10 model.

[0061] from Fig.26 and Fig.28It can be seen that even if the second absorbing body 300 is tilted in different directions, the absorbing effect produced by the absorbing unit 10 is the same, which means that when the tilt angle is the same, different tilt directions have no effect on the absorbing effect of the absorbing unit 10. However, when the second absorbing body 300 is tilted, the absorbing effect is not significantly improved compared to the vertical arrangement of the second absorbing body 300, and it may increase the difficulty of processing and the difficulty of installing and using the absorbing unit 10. Therefore, compared with the solution of tilting the second absorbing body 300, the vertical arrangement of the second absorbing body 300 is a more preferred arrangement.

[0062] Sixth, please refer to Fig.29 To Figure Fig.34 ,in, Fig.29 , Fig.31 and Fig.33 The absorbing units 10 in the embodiment all adopt the first absorbing body 200 in the shape of a four-pointed star cone, which means that each absorbing unit 10 has four absorbing parts 210; correspondingly, the number of the second absorbing bodies 300 is four. Fig.29 , Fig.31 and Fig.33 The difference between the structures shown in Fig.29 The plurality of absorbing units 10 are arranged in a transverse arrangement, and in any two adjacent absorbing units 10, two second absorbing bodies 300 are spliced ​​to form a pyramid; wherein Fig.29 In the arrangement shown in , the incident direction of the electromagnetic wave is approximately toward the position between the two absorbing parts 210 , which can also be regarded as that the incident direction of the electromagnetic wave is approximately toward the side of the first absorbing body 200 . Fig.31 The multiple absorbing units 10 are arranged in an oblique arrangement (wherein, Fig.31 The arrangement in can be seen as Fig.30 The structure in the embodiment is rotated 45°, and in any two adjacent absorbing units 10, two second absorbing bodies 300 are spliced ​​to form a pyramid; wherein, Fig.31 In the arrangement shown in , the incident direction of the electromagnetic wave is substantially toward the edge of the absorbing portion 210 away from the center of the first absorbing body 200 , which can also be regarded as the incident direction of the electromagnetic wave is substantially toward the edge of the first absorbing body 200 . Fig.33 The multiple absorbing units 10 are also arranged in an oblique manner, and in any two adjacent absorbing units 10, the two second absorbing bodies 300 are staggered and spliced. Fig.30 Indicates the corresponding Fig.29 A reflectivity curve diagram of electromagnetic waves incident at different angles obtained by simulation calculation of a structure formed by splicing multiple absorbing units 10; Fig.32 Indicates the corresponding Fig.31A reflectivity curve diagram of electromagnetic waves incident at different angles obtained by simulation calculation of a structure formed by splicing multiple absorbing units 10; Fig.34 Indicates the corresponding Fig.33 A reflectivity curve diagram of electromagnetic waves incident at different angles obtained by simulation calculation of a structure formed by splicing multiple absorbing units 10.

[0063] from Fig.30 , Fig.32 as well as Fig.34 It can be seen that compared with the horizontal arrangement, the inclined arrangement has a better absorbing effect; compared with the splicing method of two second absorbing bodies 300 spliced ​​to form a pyramid, the staggered splicing method of the second absorbing bodies 300 has a better absorbing effect.

[0064] In summary, a plurality of absorbing units 10 form an absorbing structure. When low-frequency electromagnetic waves are directly incident, the first absorbing body 200 provides the main absorbing function due to the large wavelength of the electromagnetic waves. When high-frequency electromagnetic waves are directly incident, the second absorbing body 300 can fill the gap between the first absorbing bodies 200 due to the small wavelength of the electromagnetic waves, thereby weakening the reflection of the electromagnetic waves when incident on the base 100, and assisting in increasing the absorption of the electromagnetic waves. In addition, when the electromagnetic waves are obliquely incident, the second absorbing body 300 increases the number of reflections of the electromagnetic waves between the first absorbing body 200 and the second absorbing body 300. At the same time, in the oblique incident direction, the shapes of the first absorbing body 200 and the second absorbing body 300 are both cone-like impedance gradient structures, which are conducive to the absorption of oblique incident electromagnetic waves. Based on this, the absorbing unit 10 can improve the technical problem in the prior art that it is difficult to take into account multi-angle and wide-band application scenarios.

[0065] Second embodiment

[0066] This embodiment provides an absorbing structure (not shown), which can be used in an environment such as an anechoic chamber for performing wireless performance tests to absorb reflected electromagnetic waves generated in the anechoic chamber and improve the accuracy of wireless performance tests. Fig.29 , Fig.31 and Fig.33 The structure shown in the figure can be regarded as a partial structure of the wave absorbing structure, and the way in which the plurality of wave absorbing units 10 used in the wave absorbing structure are spliced ​​and arranged can be adopted. Fig.29 , Fig.31 and Fig.33 Since the wave absorbing structure adopts the wave absorbing unit 10 in the first embodiment, it means that the wave absorbing structure can improve the technical problem of the prior art that it is difficult to take into account the application scenarios of multiple angles and wide frequency bands.

[0067] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A wave absorbing unit, characterized in that: include: A base, wherein the base is in a prism shape; A first wave absorbing body, comprising a plurality of wave absorbing parts, wherein the plurality of wave absorbing parts are all arranged on the base; The plurality of wave absorbing parts are arranged along a circumferential path, and the horizontal cross-section of the first wave absorbing body is in the shape of a polygonal star; the horizontal cross-sectional area of ​​the wave absorbing part gradually decreases from one end close to the base to one end far from the base, so that the wave absorbing part is in the shape of a cone; A plurality of second wave absorbing bodies are arranged on the base, and one second wave absorbing body is arranged between any two adjacent wave absorbing parts; the second wave absorbing bodies are pyramid-shaped, and the second wave absorbing bodies have side surfaces coplanar with the side surfaces of the base; A height of the wave absorbing portion relative to the base is greater than a height of the second wave absorbing body relative to the base.

2. The absorbing unit according to claim 1, characterized in that: The first absorbing body and the second absorbing body are fully distributed on the upper surface of the base.

3. The absorbing unit according to claim 1, characterized in that: The number of edges of the base is equal to the number of the wave absorbing parts; the number of the second wave absorbing bodies is equal to the number of the wave absorbing parts.

4. The absorbing unit according to claim 3, characterized in that: The edge of the absorbing part away from the center of the circumferential path is connected to the edge of the base; the edge of the second absorbing body close to the absorbing part is connected to the intersection line between two adjacent absorbing parts.

5. The absorbing unit according to claim 1, characterized in that: The first absorbing body, the second absorbing body and the base are integrally formed.

6. The wave absorbing unit according to claim 1, characterized in that: The second wave absorbing body is a triangular pyramid.

7. The wave absorbing unit according to claim 1, characterized in that: The number of the wave absorbing parts is four, so that the cross section of the first wave absorbing body is in the shape of a four-pointed star; Alternatively, the number of the wave absorbing parts is six, so that the cross section of the first wave absorbing body is in the shape of a hexagonal star.

8. The absorbing unit according to claim 1, characterized in that: When the side of the second absorbing body away from the absorbing part is coplanar with the side of the base, the second absorbing body is tilted so that the edge of the second absorbing body close to the absorbing part is tilted relative to the vertical plane.

9. A wave absorbing structure, characterized in that: It comprises a plurality of absorbing units according to any one of claims 1 to 8, wherein the plurality of absorbing units are spliced ​​with each other; and in any two adjacent absorbing units, two of the second absorbing bodies are spliced ​​to form a pyramid.

10. A wave absorbing structure, characterized in that: It comprises a plurality of absorbing units according to any one of claims 1 to 8, wherein the plurality of absorbing units are spliced ​​with each other; and in any two adjacent absorbing units, the two spliced ​​second absorbing bodies are arranged in a staggered manner.

Images