CN106558766A - Metamaterial composite structure and its manufacture method and antenna house - Google Patents

Abstract

The invention discloses a supermaterial composite structure, a manufacturing method thereof and a radome. The metamaterial composite structure includes: a honeycomb panel, the honeycomb panel is composed of a dielectric material, and has a plurality of honeycomb units, each honeycomb unit has a plurality of honeycomb walls; and a plurality of honeycomb walls attached to the plurality of honeycomb walls Conductive geometric structure units, wherein the plurality of conductive geometric structure units are located on the honeycomb walls with different orientations, thereby forming multiple microstructure arrays with different orientations. As the middle layer of the radome, the metamaterial composite structure not only plays a role in improving the mechanical strength, but also further improves the wave-transmitting performance of electromagnetic waves incident at large angles.

Description

Metamaterial composite structure, manufacturing method and radome

technical field

The invention relates to the field of artificial composite materials, and more specifically, to a metamaterial composite structure, a manufacturing method thereof, and a radome.

Background technique

In recent years, the research and application of metamaterials have attracted extensive attention. Metamaterials are artificial composite structures or composite materials with specific microstructures. Through the orderly design of the structure of the material on the physical scale, it is possible to break through the limitations of some natural laws, thereby exhibiting extraordinary physical properties that natural materials do not have. The physical properties of metamaterials depend not only on the intrinsic properties of the material but also on the microstructure formed in it.

Metamaterials can be formed by stacking multiple metamaterial functional plates or combining them in other regular arrays. The metamaterial functional plate includes a dielectric substrate and a plurality of conductive geometric structures forming an array on the dielectric substrate. The metamaterial functional board exhibits metamaterial properties. In order to further enhance the mechanical strength, the metamaterial functional plate and the honeycomb structure plate can also be laminated together.

One application of metamaterials is in the manufacture of radomes. The existing radome is basically a pure material radome, which can only protect the antenna and affect the performance of the antenna within the allowable range. Ordinary physical materials use the half-wavelength or quarter-wavelength theory to change their thickness corresponding to different antenna frequencies. When the thickness of the material is 1/2 of the wavelength of the electromagnetic wave in the working frequency band, the electromagnetic wave penetration rate is the best. However, if the operating wavelength is too long, the radome designed according to the half-wavelength theory will be too thick. Not only is the weight of the radome too heavy, but it also cannot meet the requirements for large-angle electromagnetic wave transmission. In addition, pure material radome has poor filtering characteristics and is susceptible to interference from adjacent frequency bands. Metamaterials consist of conductive geometric structures on a dielectric substrate that generate electromagnetic responses to electric and magnetic fields, thereby exhibiting electromagnetic properties different from those of conventional materials. Compared with pure material radome, metamaterial radome can reduce thickness and weight.

It is expected to further improve the structural design of metamaterials, so that the radome can also show excellent wave-transmitting effects for electromagnetic waves incident at large angles.

Contents of the invention

In view of the aforementioned problems, the object of the present invention is to provide a metamaterial composite structure capable of improving the wave-transmitting effect, its manufacturing method, and a radome.

According to one aspect of the present invention, there is provided a metamaterial composite structure, comprising: a honeycomb panel, the honeycomb panel is composed of a dielectric material, and has a plurality of honeycomb units, each honeycomb unit has a plurality of honeycomb walls; and A plurality of conductive geometric structure units on the plurality of honeycomb walls, wherein the plurality of conductive geometric structure units are located on the honeycomb walls with different orientations, thereby forming a plurality of microstructure arrays with different orientations.

Preferably, the honeycomb units are periodically arranged, and the honeycomb units are evenly distributed on the honeycomb plate, and adjacent honeycomb units have a common honeycomb wall.

Preferably, the shape of the plurality of honeycomb units is selected from one of polygonal, wavy, and zigzag.

Preferably, the shape of the plurality of honeycomb units is a closed polygon.

Preferably, the shape of the plurality of honeycomb units is a regular hexagon.

Preferably, at least one conductive geometric structure unit is provided in each honeycomb wall.

Preferably, a plurality of conductive geometric structure units are arranged on each honeycomb wall, and the plurality of conductive geometric structure units are periodically arranged in an array.

Preferably, the metamaterial composite structure has opposite first and second surfaces, and the plurality of honeycomb units each have openings on the first and second surfaces.

Preferably, said plurality of conductive geometrical structural units comprises a first group of conductive geometrical structural units and/or a second group of conductive geometrical structural units, said first group of conductive geometrical structural units and said second group of conductive geometrical structural units Patterns and/or sizes vary.

Preferably, the plurality of conductive geometrical structure units respectively comprise a closed ring-shaped first portion and a block-shaped second portion located inside the first portion.

Preferably, the first part is square-shaped, and the second part is square-shaped.

Preferably, the outer side length of the first part is 4.8 to 9.2 mm, and the line width is 0.05 to 1.2 mm.

According to another aspect of the present invention, a radome is provided, comprising: the above-mentioned metamaterial composite structure; and a first skin and a second skin, wherein the metamaterial composite structure is sandwiched between the first skin and the second skin. between the second skins.

Preferably, the shape of the radome is one selected from the following shapes: flat surface, curved surface, conical surface, spherical surface, and special-shaped surface.

Preferably, the surfaces of the first skin and the second skin are perpendicular to the surfaces of the plurality of honeycomb walls.

According to yet another aspect of the present invention, there is provided a method for manufacturing a metamaterial composite structure, comprising: forming a first microstructure array and a second microstructure array on opposite first and second surfaces of a dielectric substrate; and The dielectric substrate together with the first microstructure array and the second microstructure array are used as a honeycomb plate member to assemble a metamaterial composite structure, wherein the first microstructure array includes a plurality of first microstructure arrays separated by a plurality of first bonding regions. a set of conductive geometrical units, the second array of microstructures includes a plurality of second sets of conductive geometrical units separated by a plurality of second bonding areas, and the step of assembling includes utilizing the first bonding areas and The adhesive layer on at least one of the second adhesive regions bonds the adjacent honeycomb panel components together.

Preferably, the step of forming the first microstructure array and the second microstructure array is selected from one of: combining photosensitive ink with hot stamping, combining photolithography with etching, and printing with conductive ink.

Preferably, the dielectric substrate is bent using hot pressing to form the honeycomb panel member.

Preferably, the step of bending the dielectric substrate includes: for the plurality of first groups of conductive geometric structure units, bending the first group of conductive geometric structure units upward respectively to form the first group of conductive geometric structure units attached A plurality of the first set of honeycomb walls, and for the plurality of second sets of conductive geometrical units, bending the second set of conductive geometrical units downward, respectively, to form multiple cells to which the second set of conductive geometrical units are attached A second set of honeycomb walls.

Preferably, all conductive geometric structure units located on a honeycomb wall in the first group of conductive geometric structure units and the second group of conductive geometric structure units are in the same plane.

Preferably, in the step of bending the dielectric substrate, the bending angle is 120 degrees.

Preferably, the dielectric substrate is a flat dielectric substrate, and the assembling into a metamaterial composite structure includes: after bonding a plurality of the honeycomb plate components together, stretching all the dielectric substrates so that adjacent media The substrates are spaced apart from each other to form the space of the honeycomb unit.

The metamaterial composite structure fabricated according to the above steps includes a honeycomb panel with honeycomb units, and conductive geometric structure units attached to the honeycomb walls of the honeycomb units. As the middle layer of the radome, the metamaterial composite structure can not only improve the mechanical strength, but also improve the electromagnetic wave penetration rate in the working frequency band.

In addition, the plurality of conductive geometrical units are located on different orientations of the honeycomb walls, thereby forming a plurality of arrays of microstructures with different orientations. Even if the incident angle of electromagnetic waves is not perpendicular to the main surface of the metamaterial composite structure (that is, the main surface of the radome skin), the metamaterial composite structure can make it easier for electromagnetic waves in the working frequency band to penetrate. Therefore, the metamaterial composite structure can increase the incident angle of electromagnetic waves.

Description of drawings

Through the following description of the embodiments of the present invention with reference to the accompanying drawings, the above and other objects, features and advantages of the present invention will be more clear, in the accompanying drawings:

1 is a perspective view of a metamaterial composite structure according to a first embodiment of the present invention;

2 is a perspective view of a metamaterial composite structure according to a second embodiment of the present invention;

3 to 7 are schematic diagrams of various steps of a method for manufacturing a radome according to a third embodiment of the present invention, wherein Fig. 3, 5 and 7 show schematic perspective views respectively, and Fig. 4a, 4b and 4c show two directions respectively The three-dimensional schematic diagram and top view, Figures 6a and 6b show a three-dimensional schematic diagram and a cross-sectional view, respectively;

8 is a schematic perspective view of a radome according to a fourth embodiment of the present invention;

FIG. 9 shows an electromagnetic wave transmission characteristic curve of the radome shown in FIG. 8 .

detailed description

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings. In the various figures, identical elements are indicated with similar reference numerals. For the sake of clarity, various parts in the drawings have not been drawn to scale. Also, some well-known parts may not be shown. For simplicity, the structure obtained after several steps can be described in one figure.

It should be understood that when describing the structure of a device, when a layer or a region is referred to as being "on" or "over" another layer or another region, it may mean being directly on another layer or another region, or Other layers or regions are also included between it and another layer or another region. And, if the device is turned over, the layer, one region, will be "below" or "beneath" the other layer, another region.

If it is to describe the situation directly on another layer or another area, the expression "A is directly above B" or "A is above and adjacent to B" will be used herein. In the present application, "A is located directly in B" means that A is located in B, but not that A is located in a doped region formed in B.

In the following, many specific details of the present invention, such as microstructures, materials, dimensions, processing techniques and techniques, are described for a clearer understanding of the present invention. However, the invention may be practiced without these specific details, as will be understood by those skilled in the art.

The invention can be embodied in various forms, some examples of which are described below.

FIG. 1 is a schematic perspective view of a metamaterial composite structure according to a first embodiment of the present invention. The metamaterial composite structure 100 includes a honeycomb panel 110 formed of a dielectric material and a conductive geometrical unit 120 formed of a conductive material.

The honeycomb panel 110 includes honeycomb cells. The shape of the cross section of the honeycomb unit may be one of polygonal, wavy, and zigzag. In a preferred embodiment, the cross section of the honeycomb unit is a closed polygon, and in another preferred embodiment, the cross section of the honeycomb unit is a regular hexagon. The honeycomb unit includes a plurality of honeycomb walls, and the honeycomb walls with different normal vectors on the plane have different orientations. For example, V-shaped honeycomb units can provide two orientations of honeycomb walls, and honeycomb units with triangular cross-section and regular hexagonal cross-section can provide three orientations of honeycomb walls.

The honeycomb units are periodically arranged, and the honeycomb units are evenly distributed on the honeycomb board. For example, honeycomb units are arranged in periodic rows and columns.

The honeycomb unit includes a plurality of honeycomb walls, adjacent honeycomb units have a common honeycomb wall, and two surfaces of the common honeycomb wall belong to the adjacent honeycomb units respectively.

The honeycomb panel 110 may be made of any suitable dielectric material, for example: glass fiber, ceramics, aramid fiber, polytetrafluoroethylene, polymethacrylimide (polymethacrylimide, PMI), ferroelectric material, ferrite material. The honeycomb panel 110 needs to meet the requirements of providing mechanical support and hot stamping. Preferably, the honeycomb panel 110 is composed of aramid fiber.

The conductive geometrical units 120 are located on the cell walls of the cells in the honeycomb panel. The conductive geometry unit 120 includes a first portion in the shape of a closed loop, and a second portion located within the first portion. The size of the first part depends on the size of the honeycomb wall, in particular, the size of the first part is smaller than or equal to the size of the honeycomb wall. In the embodiment shown in FIG. 1 , each honeycomb unit is regular hexagonal in shape and includes six honeycomb walls, each of which has a conductive geometric structure unit 120 attached thereto. The angle between adjacent honeycomb walls is, for example, 120 degrees, and the conductive geometrical structure units 120 on adjacent honeycomb walls are adjacent to each other. The conductive geometrical unit 120 consists of a conductive material, for example of a metallic material such as gold, silver, copper or of a conductive ink.

The conductive geometric structure unit 120 includes, for example, a zigzag-shaped (hollowed-out rectangle) first portion 121 and a square-shaped second portion 122 inside the first portion. The first part 121 is a hollowed out rectangle, and the line width of the first part 121 is 4.8-9.2 mm. The second part 122 is located at the center of the rectangular hollow part of the first part 121 . It can be understood that the conductive geometric structure unit 120 located on the honeycomb wall of the honeycomb unit is not limited to the above pattern, but can be any pattern based on the simulation results.

In another example, first portions of conductive geometrical units 120 on adjacent honeycomb walls contact each other.

In this embodiment, since each honeycomb wall is attached with a conductive geometric structure unit, the size of the honeycomb unit, that is, the side length of the hexagon, and the thickness of the honeycomb plate, are approximately the same as the size of the conductive geometric structure unit 120 . The pattern and dimensions of the conductive geometrical units 120 depend on the desired electromagnetic properties. The thickness of the honeycomb panel 110 and the size of the honeycomb units are determined accordingly after designing the pattern and size of the conductive geometric structure unit 120 .

In this embodiment, the cell walls of the honeycomb elements provide the attachment surfaces for the conductive geometrical elements. The six honeycomb wall surfaces of the honeycomb units are parallel to each other in three directions, so the conductive geometric structure units 120 of the entire honeycomb panel 110 correspondingly form three microstructure arrays with different orientations.

The metamaterial composite structure described above utilizes honeycomb panels 110 to provide mechanical strength and reduce weight. Using the conductive geometric structure unit 120 on the honeycomb wall to form three different microstructure array orientations can realize large-angle electromagnetic wave transmission.

In this embodiment, the shape of the honeycomb unit is a regular hexagon, and the angle between adjacent honeycomb walls is 120 degrees. In an alternative embodiment, the shape of the honeycomb unit may be any closed polygonal shape including a plurality of honeycomb walls, and the angle between adjacent honeycomb walls is not limited to 120 degrees. The pattern and size of the conductive geometrical units on adjacent honeycomb walls may be the same or different.

In a preferred embodiment, the metamaterial composite structure has opposite first and second surfaces, and the plurality of honeycomb units have openings on both the first and second surfaces.

In another preferred embodiment, the plurality of conductive geometrical structural units of the metamaterial composite structure comprises a first group of conductive geometrical structural units and/or a second group of conductive geometrical structural units, wherein the first group of conductive geometrical structural units and the second group of conductive geometrical structural units The patterns and/or dimensions of the two sets of conductive geometrical units are different.

FIG. 2 is a schematic perspective view of a metamaterial composite structure according to a second embodiment of the present invention. The metamaterial composite structure 200 includes a honeycomb panel 210 formed of a dielectric material and a conductive geometrical unit 220 formed of a conductive material.

The metamaterial composite structure according to the second embodiment differs from the metamaterial composite structure according to the first embodiment in that in the metamaterial composite structure 200, 9 conductive geometric structure units are attached to each honeycomb wall, forming An array of 3x3 conductive geometry elements.

The size of the honeycomb unit, that is, the side length of the hexagon, depends on the size of the conductive geometric structure unit 220 and the number of conductive geometric structure units 220 arranged in this direction. The thickness of the honeycomb panel depends on the size of the conductive geometric structure unit 220 and the number of conductive geometric structure units 220 arranged in this direction.

The pattern and dimensions of the conductive geometrical units 220 depend on the desired electromagnetic properties. After designing the pattern and size of the conductive geometric structure unit 220, the quantity of the conductive geometric structure unit 220 arranged along the side length of the honeycomb unit and the conductive geometric structure unit arranged along the thickness of the honeycomb panel 210 can be further calculated according to the requirement of mechanical strength 220, so as to determine the thickness of the honeycomb panel 210 and the size of the honeycomb unit accordingly.

The metamaterial composite structure according to the second embodiment not only includes microstructure arrays with different orientations, so that large-angle electromagnetic wave transmission can be realized, but also the patterns and/or sizes of conductive geometric structure units and honeycomb units can be designed separately, so as to optimize the conduction Electromagnetic properties of geometrical units and mechanical strength of honeycomb units.

In this embodiment, the shape of the honeycomb unit is a regular hexagon, and the number of conductive geometric structure units attached to each honeycomb wall is equal. In an alternative embodiment, the shape of the honeycomb unit may be any closed polygonal shape including a plurality of honeycomb walls, and the angle between adjacent honeycomb walls is not limited to 120 degrees. The pattern, size, and number of conductive geometrical units on adjacent honeycomb walls may be the same or different. For example, the number of conductive geometric structure units on one honeycomb wall is 2×3, and the number of conductive geometric structure units on another adjacent honeycomb wall is 4×3.

3 to 7 are schematic diagrams of various steps of a method for manufacturing a metamaterial composite structure according to a third embodiment of the present invention, wherein Figs. 3 and 5-8 show schematic perspective views respectively, and Figs. A three-dimensional schematic diagram and a top view. This method is used to fabricate a metamaterial composite structure 100 as shown in FIG. 1 .

Before manufacturing the metamaterial composite structure, according to the required electromagnetic wave transmission characteristics, the shape and distribution of the conductive geometric structure units 120 are obtained through simulation design. The microstructure array includes a plurality of conductive geometric structure units 120 . Each conductive geometric structure unit 120 may be in the shape of a square, a hexagon, a square, a cross, a snowflake, or any combination thereof. According to actual needs, the sizes of the conductive geometric structure units 120 in the microstructure array can be the same or different.

In this embodiment, the conductive geometric structure unit 120 includes, for example, a square-shaped first portion 121 and a square-shaped second portion 122 located inside the first portion.

As shown in FIG. 3 , the method starts with a flat dielectric substrate 101 . The dielectric substrate 101 may be made of any suitable dielectric material, for example: glass fiber, ceramics, aramid fiber, polytetrafluoroethylene, polymethacrylimide (polymethacrylimide, PMI), ferroelectric material, ferrite material. The dielectric substrate 101 needs to meet the requirements of providing mechanical support and hot stamping. Preferably, the dielectric substrate 101 is made of aramid fiber.

The photosensitive ink is evenly coated on the dielectric substrate 101 with a screen or a spray gun. The photosensitive ink can be any type of ink. Generally, it should have excellent photosensitive performance and graphic resolution. In this embodiment, the photosensitive ink uses a transparent ultraviolet (UV) curable ink, which has excellent photosensitive performance and a minimum line width of up to 0.05 mm. After the photosensitive ink is coated on the dielectric substrate 101 by using the screen, the screen should be removed in time.

If necessary, before coating the photosensitive ink, the dielectric substrate 101 can also be pretreated, such as surface cleaning treatment, and the methods include mechanical cleaning, chemical cleaning and electrolytic cleaning.

After the photosensitive ink is coated, the photosensitive ink is dried, so that the photosensitive ink is dried and an adhesion layer is formed on the surface of the dielectric substrate 101 . For example, when using a screen to coat the photosensitive ink, the photosensitive ink can be dried in a screen oven. In addition, if hot air is used to dry the photosensitive ink, the drying temperature may be determined according to the actual situation, but should be lower than the glass transition temperature of the photosensitive ink and the material used to manufacture the dielectric substrate 101 . In this embodiment, the drying temperature is about 40 degrees.

If necessary, the steps of applying photosensitive ink and drying the photosensitive ink can be repeated to increase the thickness of the adhesion layer.

Then, a backsheet having the same pattern as the microstructure array is made, and the backsheet is overlaid on the adhesive layer. Specifically, the pattern of the microstructure array is designed by computer software such as CST, and whether it satisfies actual needs is checked by simulation test. The data related to the shape, size and arrangement of the microstructure array are transmitted to the photographic equipment, and the photographic equipment outputs a negative film (ie film) having the same image as the microstructure array.

The adhesive layer is then exposed through the negative to cure the light-receiving portion corresponding to the non-image portion of the negative. In this embodiment, the light used to irradiate the film is ultraviolet light emitted by an ultraviolet (UV) lamp. Since the adhesive layer is formed of photosensitive ink, exposure causes the pattern of the negative to be transferred into the adhesive layer. The exposed part of the adhesion layer is cured by light (becoming thermosetting), and the performance of the unexposed part remains unchanged and remains thermoplastic. After the exposure is complete, the negative can be removed. The photosensitive ink in this embodiment is a negative-type photosensitive ink, of course, the photosensitive ink can also be a positive-type photosensitive ink, as long as the positions of the light-shielding and light-leaking parts of the negative are interchanged.

Then, a conductive layer with an adhesive layer is covered on the adhesive layer. The conductive layer can be aluminum foil or copper foil. Coating an adhesive layer on the conductive layer, such as glue or other adhesives, is mainly to increase the bonding force between the conductive layer and the adhesion layer. Heat and pressurize the laminated structure consisting of the dielectric substrate 101 , the adhesive layer and the conductive layer, so that the unexposed part of the adhesive layer is melted, and the corresponding conductive layer is bonded to the dielectric substrate 101 .

For example, in this embodiment, the medium substrate 101 is placed on the electric heating base plate of the hot stamping machine. The electric heating bottom plate of the hot stamping machine is used to heat up the adhesion layer, so that the unexposed part of the adhesion layer is melted. The conductive layer is rolled using the pressure roller of the hot stamping machine. After the hot-melt portion of the adhesion layer is cured, the dielectric substrate 101 and the corresponding portion of the conductive layer are bonded together corresponding to the non-light-receiving portion of the adhesion layer. The heating temperature for the adhesion layer should be lower than the glass transition temperature of the photosensitive ink and the material used to manufacture the dielectric substrate 101 , for example, the heating temperature is between 100-130 degrees.

Then, the part of the conductive layer that is not bonded to the dielectric substrate 101 is removed, and the remaining part of the conductive layer forms a microstructure array.

By repeating the above-mentioned steps of forming microstructure arrays using photosensitive ink and hot stamping, the first microstructure array and the second microstructure array composed of conductive geometric structure units 120 are respectively formed on the two opposite surfaces 101a and 101b of the dielectric substrate 101. Arrays of structures, as shown in Figures 4a, 4b and 4c. In FIG. 4 c , for the sake of clarity, oblique lines are used to indicate the conductive layer pattern formed on the dielectric substrate 101 .

As shown in FIG. 4a, on the surface 101a of the substrate 101, the conductive geometric structure units of the first microstructure array are divided into multiple groups of conductive geometric structure units, and each group of conductive geometric structure units includes three conductive geometric structure units arranged in a row and adjacent to each other. The structural units 120 a , 120 b , 120 c , different groups of conductive geometrical structural units are separated by a first bonding area 125 whose size corresponds to the size of one conductive geometrical structural unit 120 .

As shown in Figure 4b, on the surface 101b of the substrate 101, the conductive geometric structure units of the second microstructure array are divided into multiple groups of conductive geometric structure units, and each group of conductive geometric structure units includes three conductive geometric structure units arranged in a row and adjacent to each other. The structural units 120d , 120e , 120f , different sets of conductive geometrical structural units are separated by a second bonding area 126 whose size corresponds to the size of one conductive geometrical structural unit 120 . The second bonding area 126 coincides with the projection of the conductive geometric structure unit 120b on the surface 101a. In this embodiment, the dielectric substrate 101 will be used to form a honeycomb panel, as will be described below. Each conductive geometry unit 120 will be attached to one of the cell walls of the cell respectively. The first bonding area 125 and the second bonding area 126 are staggered from each other, so that the first bonding area 125 corresponds to the position and size of a conductive geometric structure unit 120, and the second bonding area 126 corresponds to the position and size of a conductive geometric structure unit 120. corresponding to the location and size.

Then, according to the mechanical properties of the dielectric substrate 101 , the dielectric substrate 101 is bent by using a hot pressing process, as shown in FIG. 5 . In this embodiment, each group of conductive geometric structure units 120a, 120b, 120c of the first microstructure array is bent upwards, and each group of conductive geometric structure units 120d, 120e, 120f of the second microstructure array is bent downward.

Each group of conductive geometrical structure units 120a, 120b, 120c will form three adjacent honeycomb walls among the six honeycomb walls of a honeycomb unit, which are bent upward to form an angle of 120 degrees to each other. Each group of conductive geometrical units 120d, 120e, 120f will form three adjoining honeycomb walls of the six honeycomb walls of the adjacent other honeycomb unit, bent downwards into a shape with an angle of 120 degrees to each other.

On the first surface of the dielectric substrate 101 , each first bonding area 125 connects two adjacent groups of conductive geometric structure units 120 a , 120 b , 120 c of the first microstructure array. On the opposite second surface of the dielectric substrate 101 , each second bonding area 126 connects two adjacent groups of conductive geometric structure units 120 d , 120 e , 120 f of the second microstructure array.

The dielectric substrate 101 and the first microstructure array and the second microstructure array on its two opposite surfaces together form a honeycomb plate member 102 .

Then, the honeycomb panel member 102 and the honeycomb panel member 103 are assembled together, as shown in Figs. 6a and 6b. The honeycomb panel member 102 and the honeycomb panel member 103 respectively have the same structure as shown in FIG. 5 . Figures 6a and 6b are schematic views of forming honeycomb units by bonding honeycomb plate components 102 and 103, wherein Figure 6b is a cross-sectional view of the dotted line area in Figure 6a.

During assembly, an adhesive is applied on at least one of the first bonding area 125 of the honeycomb panel member 102 and the first bonding area 125 of the honeycomb panel member 103, thereby forming an adhesive layer. The adhesive layer may consist of any conventional heat or light curing adhesive, such as epoxy. The first bonding region 125 of the honeycomb panel member 102 and the first bonding region 125 of the honeycomb panel member 103 are relatively close, and the honeycomb panel member 102 and the honeycomb panel member 103 are bonded together by an adhesive layer, thereby forming a honeycomb panel laminated. Depending on the nature of the adhesive, the adhesive can be cured by heating or light irradiation.

Each group of conductive geometric structure units of the first microstructure array of the honeycomb plate member 102, together with a corresponding group of conductive geometric structure units of the first microstructure array of the honeycomb plate member 103, form six honeycomb walls adjacent to each other of a honeycomb unit . Adjacent honeycomb walls are at an angle of 120 degrees to each other.

The first bonding area 125 of the honeycomb panel member 102 and the corresponding first bonding area 125 of the honeycomb panel member 103 connect two adjacent honeycomb units.

In a preferred embodiment, the first bonding area 125 and the second bonding area 126 are bonded by pressure bonding.

Then, the honeycomb plate components 102 and 103 and the honeycomb plate components 104-106 are sequentially bonded together to form a metamaterial composite structure 100, as shown in FIG. 7 .

When bonding each honeycomb panel component, the first bonding area and the second bonding area are used alternately to bond two adjacent honeycomb panel components.

The dielectric substrates of all of the honeycomb panel structures 102-106 described above are bonded together. The dielectric substrates together form a honeycomb panel. On the six honeycomb walls of each honeycomb unit of the honeycomb panel, a conductive geometric structure unit 120 is respectively attached,

In this embodiment, microstructure arrays are formed on two opposite surfaces of the dielectric substrate 101 using photosensitive ink and hot stamping.

In an alternative embodiment, conductive ink may be used to directly form the pattern of microstructure units on the dielectric substrate 101 , and in this case, the conductive ink directly serves as a conductive layer. In another alternative embodiment, photolithography and etching may be used to pattern the metal layer on the dielectric substrate 101 into microstructure units.

In addition, in this embodiment, the dielectric substrate 101 is hot-pressed and bent into a honeycomb panel member 102, the angle between adjacent conductive geometric structural units is 120 degrees, and multiple honeycomb panel members are assembled together by bonding.

In an alternative embodiment, in the above hot pressing step, the included angle between the adjacent conductive geometric structure units of the dielectric substrate 101 can be arbitrary. As long as the final formed honeycomb unit can form a closed hexagon.

In another alternative embodiment, according to the mechanical properties of the dielectric substrate 101 , the step of thermally pressing and bending the dielectric substrate 101 into the honeycomb panel member 102 may be omitted. For example, in the case that the dielectric substrate 101 is composed of aramid fiber, the flat dielectric substrates can be bonded together, and all the dielectric substrates can be stretched together so that the adjacent dielectric substrates are separated by a certain distance to form a honeycomb unit space.

FIG. 8 is a schematic perspective view of a radome according to a fourth embodiment of the present invention. The radome 105 includes a first skin 150 , a second skin 160 , and the metamaterial composite structure 100 sandwiched between the first skin 150 and the second skin 160 . The metamaterial composite structure 100 has, for example, the structure shown in FIG. 1 .

The first skin 150 and the second skin 160 are used as shell materials, such as glass fiber or epoxy resin. The metamaterial composite structure 100 provides mechanical strength. Moreover, since the metamaterial composite structure 100 includes conductive geometric structures, it is easier for electromagnetic waves incident at large angles to penetrate the metamaterial composite structure 100 .

In a preferred embodiment, in order to protect the radome, the outer surfaces of the first skin 150 and the second skin 160 can be coated with a protective layer for anti-acid, anti-corrosion, anti-abrasion and the like.

In this embodiment, the radome 105 has a planar shape. In an alternative embodiment, the metamaterial composite structure of the radome according to the present invention can be a thin layer material of any shape such as a plane, a curved surface, a conical surface, a spherical surface, a special-shaped surface, etc., and can also include a soft film, depending on the application requirements. different.

FIG. 9 shows an electromagnetic wave transmission characteristic curve of the radome shown in FIG. 8 . In this preferred embodiment, the first skin 150 and the second skin 160 of the radome have a relative permittivity of 2.85, a loss of 0.005, and a thickness of 0.6 mm. The relative permittivity of the honeycomb panel 110 is 1.05, and the loss is 0.0045. The outer length of the first part 122 of the shape of the conductive geometric structure unit is 7 mm, and the line width is 0.8 mm; the length, width and thickness of the second part 122 of the square shape are respectively 1.4 mm, 1.4 mm, and 0.018 mm. The second portion 122 is silver.

As shown in Figure 9, the simulation results when the electromagnetic wave (TE mode, TM mode) irradiates the radome shows that for the electromagnetic wave of 12.5GHz-17.5GHz, the electromagnetic wave transmission coefficient value of the radome is close to 1, indicating that the electromagnetic wave transmittance Very high, acting like solid air. The metamaterial composite structure 100 of the present invention not only ensures high wave penetration in the working frequency band, but also filters signals outside the working frequency band, providing a better protection environment for the normal operation of the antenna.

The radome according to the present invention has a certain mechanical strength to protect the antenna therein, and ensures high wave penetration in the working frequency band, and plays a role in filtering signals outside the working frequency band, providing a better protection environment for the normal operation of the antenna .

In the above description, technical details such as patterning and etching of each layer are not described in detail. However, those skilled in the art should understand that various technical means can be used to form layers, regions, etc. of desired shapes. In addition, in order to form the same structure, those skilled in the art can also design a method that is not exactly the same as the method described above. In addition, although the various embodiments are described above separately, this does not mean that the measures in the various embodiments cannot be advantageously used in combination.

The embodiments of the present invention have been described above. However, these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. The scope of the invention is defined by the appended claims and their equivalents. Those skilled in the art can make various substitutions and modifications without departing from the scope of the present invention, and these substitutions and modifications should all fall within the scope of the present invention.

Claims (22)

1. A metamaterial composite structure, comprising: a honeycomb panel consisting of a dielectric material and having a plurality of honeycomb cells each having a plurality of cell walls; and a plurality of conductive geometrical structural units attached to the plurality of honeycomb walls, Wherein, the plurality of conductive geometric structure units are located on at least two honeycomb walls with different orientations, thereby forming multiple microstructure arrays with different orientations. 2. The metamaterial composite structure according to claim 1, wherein the honeycomb units are periodically arranged, and the honeycomb units are uniformly distributed on the honeycomb plate, and adjacent honeycomb units have common honeycomb walls. 3. The metamaterial composite structure according to claim 2, wherein the cross-sectional shape of the plurality of honeycomb units is a shape selected from one of polygonal, wavy, and zigzag. 4. The metamaterial composite structure according to claim 3, wherein the cross-sectional shape of the plurality of honeycomb units is a closed polygon. 5. The metamaterial composite structure according to claim 4, wherein the cross-sectional shape of the plurality of honeycomb units is a regular hexagon. 6. The metamaterial composite structure according to any one of claims 1-5, wherein at least one conductive geometric structure unit is provided in each honeycomb wall. 7. The metamaterial composite structure according to claim 6, wherein a plurality of conductive geometric structure units are provided on each honeycomb wall, and the plurality of conductive geometric structure units are periodically arranged in an array. 8. The metamaterial composite structure according to claim 1, wherein the metamaterial composite structure has a first surface and a second surface opposite, and the plurality of honeycomb units are located between the first surface and the second surface. Both surfaces have openings. 9. The metamaterial composite structure according to claim 8, wherein said plurality of conductive geometrical units comprises a first set of conductive geometrical units and/or a second set of conductive geometrical units, said first set of conductive geometrical units The pattern and/or size of the structural elements and said second set of conductive geometrical structural elements are different. 10. The metamaterial composite structure of claim 7, wherein the plurality of conductive geometrical units each comprise a closed loop-shaped first portion and a block-shaped second portion within the first portion. 11. The metamaterial composite structure according to claim 10, wherein the first portion is square-shaped and the second portion is square-shaped. 12. The metamaterial composite structure of claim 11, wherein the first portion has an outer side length of 4.8 to 9.2 mm and a line width of 0.05 to 1.2 mm. 13. A radome comprising: A metamaterial composite structure according to any one of claims 1 to 12; and first skin and second skin, Wherein the metamaterial composite structure is sandwiched between the first skin and the second skin. 14. The radome according to claim 13, wherein the shape of the radome is one selected from the following shapes: flat surface, curved surface, conical surface, spherical surface, and special-shaped surface. 15. The radome of claim 13 or 14, wherein the surfaces of the first skin and the second skin are perpendicular to the surfaces of the plurality of honeycomb walls. 16. A method of fabricating a metamaterial composite structure comprising: Forming a first microstructure array and a second microstructure array on opposite first and second surfaces of the dielectric substrate, respectively; and The dielectric substrate together with the first microstructure array and the second microstructure array are used as a honeycomb plate member to assemble a metamaterial composite structure, Wherein the first microstructure array includes a plurality of first conductive geometric structure units separated by a plurality of first bonding regions, and the second microstructure array includes a plurality of conductive geometric structure units separated by a plurality of second bonding regions. a second set of conductive geometry units, and The assembling step includes: using the adhesive layer on at least one of the first adhesive region and the second adhesive region to bond the adjacent honeycomb panel components together. 17. The method according to claim 16, wherein the step of forming the first array of microstructures and the second array of microstructures is selected from the group consisting of: using a combination of photosensitive ink and hot stamping, using a combination of photolithography and etching , and one of printing with conductive ink. 18. The method of claim 16, wherein the dielectric substrate is bent using hot pressing to form the honeycomb panel member. 19. The method of claim 18, wherein bending the dielectric substrate comprises: For the plurality of first set of conductive geometrical units, each of the first set of conductive geometrical units is bent upwardly to form a plurality of first set of honeycomb walls to which the first set of conductive geometrical units are attached, and For the plurality of second sets of conductive geometrical units, the second set of conductive geometrical units are respectively bent down to form a plurality of second sets of honeycomb walls to which the second set of conductive geometrical units are attached. 20. The method of claim 19, wherein all conductive geometrical units of the first set and the second set of conductive geometrical units located on a cell wall lie in the same plane. 21. The method according to claim 20, wherein, in the step of bending the dielectric substrate, the bending angle is 120 degrees. 22. The method according to claim 16, wherein the dielectric substrate is a flat dielectric substrate, and the assembling into a metamaterial composite structure comprises: After a plurality of the honeycomb panel members are bonded together, all the dielectric substrates are stretched so that adjacent dielectric substrates are separated from each other by a certain distance to form the spaces of the honeycomb units.