CN102904057A - A new artificial electromagnetic material - Google Patents

Abstract

The invention provides a novel manual electromagnetic material which comprises a piece-shaped substrate and at least one pair of artificial micro-structures. Each pair of artificial micro-structures comprises a first artificial micro-structure and a second artificial micro-structure which are adhered to the substrate, and a plurality of artificial micro-structures are arranged on the piece-shaped substrate in an array mode. Two harmonic peaks are obtained through two different artificial micro-structures, and smooth gradual change of epsilon from zero can be achieved between the two harmonic peaks. In addition, according to comparison of simulated images, we can know that the size of the artificial micro-structures can enable the harmonic peaks to move forward or backward in a certain frequency range, and then a smooth gradual-changing frequency range of a dielectric constant from zero is adjusted, wherein a change rule is specifically that the harmonic peaks move backward if size of the artificial micro-structures is decreased; and the harmonic peaks move forward if size of the artificial micro-structures is increased.

Description

A new artificial electromagnetic material

【Technical field】

The invention relates to the electromagnetic field, and more specifically, relates to a novel artificial electromagnetic material.

【Background technique】

Artificial electromagnetic material, commonly known as metamaterial, is a new type of artificial synthetic material, which is composed of a substrate made of non-metallic materials and multiple artificial microstructures attached to the surface of the substrate or embedded in the interior of the substrate. The substrate can be virtually divided into multiple square substrate units arranged in a rectangular array. Each substrate unit is attached with an artificial microstructure to form a metamaterial unit. The entire metamaterial is composed of hundreds of thousands, millions or even hundreds of millions of It is composed of such metamaterial units, just like a crystal is composed of countless lattices according to a certain arrangement. The artificial microstructures on each metamaterial unit are identical or not identical. Artificial microstructures are cylindrical or flat metal wires that form a certain geometric figure, such as ring-shaped, I-shaped metal wires, etc.

Due to the existence of artificial microstructures, each metamaterial unit has an equivalent permittivity and an equivalent magnetic permeability different from the substrate itself, so all metamaterial units composed of metamaterials exhibit special response characteristics to electric and magnetic fields ; At the same time, designing different specific structures and shapes for artificial microstructures can change the equivalent dielectric constant and equivalent magnetic permeability of its units, and then change the response characteristics of the entire metamaterial.

The dielectric constant is the ratio of the capacitance of a capacitor of the same size made of an insulating material as a medium and a vacuum as a medium. It is usually represented by the Greek letter ε, which indicates the amount of electrostatic energy accumulated in a unit volume in a unit electric field. The dielectric constant characterizes the ability of a dielectric to polarize and store charge. If a material with a high dielectric constant is placed in the electric field, the strength of the electric field will drop appreciably within the dielectric. In high dielectric constant materials, the wavelength of electromagnetic waves is very short, which can greatly reduce the size of radio frequency and microwave devices. The variation range of the dielectric constant of most existing materials is very small, and the dielectric constant is usually greater than zero.

In the existing artificial electromagnetic material design and production process, I-shaped artificial microstructures are usually used to change the dielectric constant distribution in space. The distribution of permittivity produced by this structure usually produces only one resonant resonance in the frequency band of interest, so the range of permittivity change is relatively small, and usually starts to change from a relatively large value. However, practical applications usually require Dielectric constant varying from zero.

【Content of invention】

The purpose of the embodiments of the present invention is to provide a new type of artificial electromagnetic material, which has a wide-band high dielectric constant in a certain frequency band and a dielectric constant distribution that gradually increases from zero in another frequency band. The embodiment of the present invention is achieved in this way, a novel artificial electromagnetic material, said material comprising:

A sheet substrate, an artificial microstructure attached to the sheet substrate, the artificial microstructure has at least one pair, each pair of artificial microstructures includes a first artificial microstructure and a second artificial microstructure attached to the substrate structure.

The embodiment of the present invention obtains two resonant peaks through two different artificial microstructures, so that ε can be smoothly and gradually changed from zero between the two resonant peaks, and it can be seen from the comparison of the simulation diagrams that changing the size of the artificial microstructure It can make the resonance peak move forward or backward within a certain frequency band, and then adjust the frequency band where ε smoothly and gradually changes from zero. The specific change law is: reducing the size of the microstructure can widen the bandwidth of the frequency band described by ε, and the resonance peak Move back; increasing the size of the microstructure can broaden the bandwidth of the frequency band described by ε, and move the resonance peak forward, and the artificial electromagnetic material has a wide frequency and high dielectric constant in front of the first resonance peak, which can meet the requirements of specific occasions. need.

【Description of drawings】

Fig. 1 shows the structural diagram of the artificial electromagnetic material provided by preferred embodiment one of the present invention;

Fig. 2 shows the structural diagram of the artificial electromagnetic material provided by the second preferred embodiment of the present invention;

Fig. 3 shows the simulation schematic diagram of the dielectric constant of the artificial electromagnetic material provided by the preferred embodiment of the present invention;

Fig. 4 shows the simulation schematic diagram of the dielectric constant of the artificial electromagnetic material provided by the preferred embodiment 2 of the present invention;

Figure 5 shows another embodiment of the first artificial microstructure provided by the embodiment of the present invention;

FIG. 6 shows data corresponding to the artificial microstructure provided by Embodiment 1 of the present invention.

【Detailed ways】

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

The embodiment of the present invention obtains two resonant peaks through two different artificial microstructures, so that ε can be smoothly and gradually changed from zero between the two resonant peaks, and it can be seen from the comparison of the simulation diagrams that changing the size of the artificial microstructure It can make the resonance peak move forward or backward within a certain frequency band, and then adjust the frequency band where ε smoothly and gradually changes from zero. The specific change law is: reducing the size of the microstructure can widen the bandwidth of the frequency band described by ε, and the resonance peak Move back; increasing the size of the microstructure can widen the bandwidth of the frequency band described by ε, and move the resonance peak forward, and the electromagnetic material has a wide frequency and high dielectric constant in front of the first resonance peak, which can meet the needs of specific occasions .

As shown in Figure 1, it is a structural diagram of the artificial electromagnetic material provided by the preferred embodiment of the present invention. For the convenience of description, only the parts related to the embodiment of the present invention are shown, including:

A sheet substrate 1 , an artificial microstructure 2 attached to the substrate 1 .

In the embodiment of the present invention, the substrate is usually made of materials such as epoxy resin, polytetrafluoroethylene, ceramics, etc., and the artificial microstructure is a planar structure with a certain geometric pattern composed of metal wires such as silver wires or copper wires. Each substrate can be virtually divided into a plurality of cube-shaped grids with equal length and width, the thickness of each grid is equal to the thickness of the substrate, and the length and width are not greater than one-tenth of the wavelength of the incident electromagnetic wave to be responded. Each cube-shaped grid is a substrate unit, and each substrate unit and the artificial microstructure attached to its surface constitute a material unit. Each material sheet can be regarded as a row of these material units with the width of a material unit. The spacing and length are obtained by arraying the column spacing.

Each substrate unit is attached with at least one pair of artificial microstructures, including: a first artificial microstructure and a second artificial microstructure, and the first and second artificial microstructures are combined to form a new artificial microstructure, so that the dielectric substrate 1 exhibit different dielectric constants. And the first and second artificial microstructures are two ELC structures with different sizes. And the first artificial microstructure and the second artificial microstructure can be interchanged.

As shown in FIG. 1 , the first artificial microstructure is a snowflake structure formed by two I-shaped metal rings intersecting at 90°. The second artificial microstructure is similar to the first artificial microstructure 1, except that two I-shaped metal rings intersect at 90°, and also include a metal that extends from each I-shaped transverse edge to the intersection point but does not touch Wire.

It should be pointed out that the bending of the I-shaped transverse side of the second artificial microstructure includes but is not limited to: bending toward the intersection point at a certain degree, bending toward the intersection point in an arc shape; The end line of the transverse side of the font can be a straight line or an arc; in addition, the first artificial microstructure and the second artificial microstructure can be interchanged.

As shown in Figure 2, the structural diagram of the artificial electromagnetic material provided for the preferred embodiment two of the present invention, in the preferred embodiment two, the I-shaped lateral side of the first artificial microstructure has extended the size, that is, the first one has been enlarged. The lateral dimension of the artificial microstructure.

It should be pointed out that the size of the second artificial microstructure provided by preferred embodiments 1 and 2 is the same as that of the first artificial microstructure, and the center point of the second artificial microstructure is located at the center point of the first artificial microstructure. Horizontal or vertical extension line.

Fig. 3 shows the simulation schematic diagram of the dielectric constant of the artificial electromagnetic material that preferred embodiment 1 of the present invention provides, and each simulation parameter is as shown in Fig. 6, wherein S2 is 0.1mm, S3 is 0.7mm, S4 is 1mm, the second The bending angle of the microstructure is 45°, 2.1mm for S5, 0.7mm for S6, and 0.4mm for S7. It can be seen from Fig. 3 that the artificial electromagnetic material provided by preferred embodiment ₁ has a first resonance peak at f1 of 9.4GHZ, a second resonance peak at _f2 of 12.5GHZ, and _f3 between the two resonance peaks is 10.4 In GHZ, ε is zero, and in the frequency band where f is 10.4-11GHZ, the dielectric constant changes slowly from zero, and the bandwidth is 0.6GHZ.

Fig. 4 is a simulation schematic diagram of the dielectric constant of the artificial electromagnetic material provided by the preferred embodiment 2 of the present invention, the corresponding data is the same as Fig. 6, only S3 is changed to 2mm. It can be seen from Fig. 4 that the artificial electromagnetic material provided by the preferred embodiment 2 has the first resonance peak at _f4 of 9.2GHZ, the second resonance peak of 10.5GHZ at _f5 , and the appearance of _f6 at 10GHZ between the two resonance peaks The case where ε is zero.

It can be seen from the simulation schematic diagrams of Fig. 3 and Fig. 4 that the embodiment of the present invention obtains two resonant peaks through two different artificial microstructures, so that ε can be smoothly and gradually changed from zero between the two resonant peaks, and by the simulation It can be seen from the comparison of the figures that changing the size of the artificial microstructure can make the resonance peak move forward or backward within a certain frequency band, and then adjust the frequency band where ε changes smoothly and gradually from zero. Specifically: reducing the size of the microstructure can make the ε frequency band When the bandwidth is widened, the resonance peak moves backward; increasing the size of the microstructure can widen the bandwidth of the ε frequency band, and the resonance peak moves forward.

In the above embodiments, the present invention is only described as an example, but those skilled in the art can make various modifications to the present invention without departing from the spirit and scope of the present invention after reading this patent application.

Claims (10)

1. novel artificial electromagnetic material, comprise: plate shape substrates, be attached to the artificial micro-structural on the described plate shape substrates, it is characterized in that, described artificial micro-structural has at least one pair of, every pair of artificial micro-structural comprises the first artificial micro-structural and the second artificial micro-structural that is attached on the described substrate, and array is placed with a plurality of artificial micro-structurals on the described plate shape substrates.

2. artificial electromagnetic material as claimed in claim 1 is characterized in that, the described first artificial micro-structural is different with the shape of the second artificial micro-structural.

3. artificial electromagnetic material as claimed in claim 2 is characterized in that, the described second artificial micro-structural is by the first artificial Microstructure evolution.

4. artificial electromagnetic material as claimed in claim 3, it is characterized in that, the described first artificial micro-structural is 90 ° by two I shapes and intersects the snowflake structure that consists of, the second artificial micro-structural except be by two I shapes 90 ° intersect, also comprise from the horizontal edge bending of each I shape and extending but discontiguous metal wire to intersection point.

5. artificial electromagnetic material as claimed in claim 4 is characterized in that, the horizontal edge bending of described I shape comprises: be the number of degrees and bend to intersection point; Being circular-arc bends to intersection point.

6. artificial electromagnetic material as claimed in claim 5 is characterized in that, the horizontal edge of described I shape comprises: straight line is remained silent, circular-arc remaining silent.

7. artificial electromagnetic material as claimed in claim 1 is characterized in that, the central point of described the second artificial micro-structural is positioned on the perpendicular or parallel extended line of the first artificial micro-structural central point.

8. artificial electromagnetic material as claimed in claim 1 is characterized in that, described artificial electromagnetic material comprises the multilayer chip substrate.

9. artificial electromagnetic material according to claim 1 is characterized in that, described artificial micro-structural is made by copper cash or silver-colored line.

10. artificial electromagnetic material according to claim 1 is characterized in that, described plate shape substrates is made by polytetrafluoroethylene, epoxy resin or pottery.

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