Metamaterial electromagnetic lens

Abstract

The metamaterial electromagnetic lens comprises a substrate, four metal trunks and metal branches, the four metal trunks are formed on the substrate and made of metamaterials, the metal branches are arranged at the two ends of each metal trunk respectively, the four metal trunks jointly intersect at a first intersection, the first intersection is the middle point of each metal trunk, each metal branch comprises a first branch, a second branch and a third branch, the metal rod is vertically arranged at the tail end of the metal trunk; the second branch is arranged between the first intersection point and the first branch, is vertical to the metal trunk and is intersected at the middle point of the second branch; the third branch is arranged between the first intersection point and the second branch, is vertical to the metal trunk and is intersected at the middle point of the third branch; the two fourth branches are symmetrically arranged on the two sides of the metal trunk, and the two fourth branches intersect with the two ends of the first branch and the two ends of the second branch respectively; the two fifth branches are symmetrically arranged on the two sides of the metal trunk and extend from the third branch to the first intersection point. Compared with the existing SSR, the electromagnetic lens disclosed by the invention has more excellent performance.

Description

Technical Field

[0001] The present invention relates to the field of electronic communications, and in particular to a metamaterial electromagnetic lens. Background Art

[0002] Electromagnetic metamaterials do not refer to new materials, but to a type of electrical parameter microstructures, which are artificial structures composed of periodic or non-periodic arrangements of subwavelength units. The microstructures in electromagnetic metamaterials will induce electric fields and participate in radiation, thus showing negative refraction characteristics that are not found in nature. When electromagnetic waves pass through electromagnetic metamaterials, negative refraction will occur. Taking microstrip antennas as an example, the transmitting source radiates electromagnetic waves outward, and when the electromagnetic waves pass through metamaterials, negative refraction will occur, which will focus the electromagnetic wave beam and make the antenna more directional. The antenna gain is equal to the product of the directivity coefficient and the antenna efficiency. When the antenna efficiency remains unchanged, the antenna gain will increase. Therefore, electromagnetic metamaterials can increase the gain of the antenna. It is difficult to apply metamaterials alone in practice, as they require a carrier. The electromagnetic lens is to print the metamaterial on a circuit board carrier and use this characteristic of the metamaterial to increase the gain of the antenna.

[0003] The S parameter extraction method was proposed by the Smith team, who designed the classic Split Ring Resonator (SSR) electromagnetic lens unit, which is a bidirectional open resonator ring. Please refer to Figure 1 Since the advent of the S-parameter extraction method, people have designed a variety of metamaterials based on this method. From the SRR, we can see that the metamaterial structure is symmetrical, and an electric field will be induced in the two split rings. The change in the electric field will cause the current to flow back and forth in the ring. The performance of the classic split ring resonator still needs to be improved. Summary of the invention

[0004] In order to solve at least one technical problem in the prior art, the present invention aims to provide a metamaterial electromagnetic lens unit.

[0005] The metamaterial electromagnetic lens disclosed in the present invention comprises a substrate and four metal trunks made of metamaterial formed on the substrate and metal branches respectively arranged at both ends of each metal trunk, wherein the four metal trunks intersect at a first intersection point, which is the midpoint of each metal trunk, and each metal branch comprises: a first branch vertically arranged at the end of the metal trunk, wherein the metal trunk intersects with the first branch at the midpoint of the first branch; a second branch arranged between the first intersection point and the first branch, perpendicular to the metal trunk and intersecting at a second intersection point, wherein the second intersection point is the midpoint of the second branch; a third branch arranged between the first intersection point and the second branch, perpendicular to the metal trunk and intersecting at a third intersection point, wherein the third intersection point is the midpoint of the third branch; two fourth branches symmetrically arranged on both sides of the metal trunk, wherein the two fourth branches intersect with both ends of the first branch and both ends of the second branch respectively; and two fifth branches symmetrically arranged on both sides of the metal trunk, extending from the third branch toward the first intersection point.

[0006] In some embodiments, the two fourth branches are parallel to the metal trunk, respectively, and extend from both ends of the second branch in a direction away from the first intersection and intersect with both ends of the first branch, and cross the first branch to form an extension portion.

[0007] In some embodiments, the two fifth branches are parallel to the metal trunk.

[0008] In some embodiments, the length of the metal trunk is 29.40±0.05 cm, the length L1 of the first branch and the second branch is 6.20±0.05 cm, the length L2 of the third branch is 3.20±0.05 cm, the length L3 of the fourth branch is 3.20±0.05 cm, the length L4 of the fifth branch is 2.20±0.05 cm, the length L5 of the extension (341) is 0.90±0.05 cm, their width is 0.40±0.05 cm, the spacing d1 between the first branch and the second branch is 1.50±0.05 cm, and the spacing d2 between the second branch and the third branch is 2.00±0.05 cm.

[0009] In some embodiments, the length of the metal trunk is 29.40±0.02 cm, the length L1 of the first branch and the second branch is 6.20±0.02 cm, the length L2 of the third branch is 3.20±0.02 cm, the length L3 of the fourth branch is 3.20±0.02 cm, the length L4 of the fifth branch is 2.20±0.02 cm, the length L5 of the extension (341) is 0.90±0.02 cm, their width is 0.40±0.02 cm, the spacing d1 between the first branch and the second branch is 1.50±0.02 cm, and the spacing d2 between the second branch and the third branch is 2.00±0.02 cm.

[0010] In some embodiments, the length of the metal trunk is 29.40±0.02 cm, the length L1 of the first branch and the second branch is 6.20±0.01 cm, the length L2 of the third branch is 3.20±0.01 cm, the length L3 of the fourth branch is 3.20±0.01 cm, the length L4 of the fifth branch is 2.20±0.01 cm, the length L5 of the extension (341) is 0.90±0.01 cm, their width is 0.40±0.01 cm, the spacing d1 between the first branch and the second branch is 1.50±0.01 cm, and the spacing d2 between the second branch and the third branch is 2.00±0.01 cm.

[0011] In some embodiments, the length of the metal trunk is 29.40 cm, the length L1 of the first branch and the second branch is 6.20 cm, the length L2 of the third branch is 3.20 cm, the length L3 of the fourth branch is 3.20 cm, the length L4 of the fifth branch is 2.20 cm, the length L5 of the extension (341) is 0.9 cm, their width is 0.4 cm, the spacing d1 between the first branch and the second branch is 1.5 cm, and the spacing d2 between the second branch and the third branch is 2 cm.

[0012] In some embodiments, the substrate is a FR-4 board, and the length, width, and thickness of the substrate are 50 mm, 50 mm, and 0.6 mm, respectively.

[0013] The electromagnetic lens disclosed in the present invention has a more superior performance than the existing SSR. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0015] Figure 1 It is a schematic diagram of the SSR structure in the prior art.

[0016] Figure 2 is a schematic diagram of a metamaterial electromagnetic lens in some examples of the present disclosure.

[0017] Figure 3 yes Figure 2 A partial schematic diagram of the metamaterial electromagnetic lens shown.

[0018] Figure 4 is the S parameter amplitude of the metamaterial electromagnetic lens of the present disclosure obtained by simulation.

[0019] Figure 5 is an S-parameter phase curve of the metamaterial electromagnetic lens of the present disclosure obtained by simulation.

[0020] Figure 6a-6d They are the relative dielectric constant, magnetic permeability, equivalent impedance and refractive index of the metamaterial electromagnetic lens of the present invention obtained through simulation.

[0021] Figure 7a-7c 1 is the surface electric field intensity distribution of the metamaterial electromagnetic lens of the present disclosure obtained by simulation at frequencies of 1 GHz, 2.45 GHz and 4 GHz respectively.

[0022] Figure 8 is the S parameter of the electromagnetic lens in the comparative example.

[0023] Figures 9a-9d They are the relative dielectric constant, magnetic permeability, equivalent impedance and refractive index of the electromagnetic lens in the comparative example obtained by simulation. DETAILED DESCRIPTION

[0024] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0025] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying 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 limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0026] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] Reference below Figure 2-Figure 3 A metamaterial electromagnetic lens unit according to an embodiment of the present disclosure is described.

[0028] The metamaterial electromagnetic lens unit includes a substrate 1, four metal trunks 2 made of metamaterial formed on the substrate 1, and eight metal branches 3 arranged at both ends of each metal trunk 2. The four metal trunks 2 intersect at a first intersection point J1, which is the midpoint of each metal trunk 2. The angles between adjacent metal trunks 2 are equal. Each metal branch 3 includes:

[0029] The first branch 31 is vertically disposed at the end of the metal trunk 2, and the metal trunk 2 and the first branch 31 intersect at the midpoint of the first branch 31;

[0030] The second branch 32 is disposed between the first intersection point J1 and the first branch 31, is perpendicular to the metal trunk 2 and intersects at the second intersection point J2, and the second intersection point J2 is the midpoint of the second branch 32;

[0031] The third branch 33 is disposed between the first intersection point J1 and the second branch 32, is perpendicular to the metal trunk 2 and intersects at a third intersection point J3, and the third intersection point J3 is the midpoint of the third branch 33;

[0032] Two fourth branches 34 are symmetrically arranged on both sides of the metal trunk 2. The two fourth branches 34 extend from two ends of the second branch 32 in a direction away from the first intersection point J1 and intersect with two ends of the first branch 31.

[0033] The two fifth branches 35 are symmetrically disposed on both sides of the metal trunk 2 , and extend from two ends of the fourth branch 34 toward the first intersection J1 .

[0034] Preferably, the two fourth branches 34 are parallel to the metal trunk 2 , respectively, and extend from both ends of the second branch 32 in a direction away from the first intersection J1 and intersect with both ends of the first branch 31 , and cross the first branch 31 to form an extension portion 341 .

[0035] Preferably, the two fifth branches 35 are parallel to the metal trunk (2.

[0036] The metal trunk 2 and metal branches 3 made of metamaterial constitute a metamaterial electromagnetic lens.

[0037] In some examples, the material of the substrate 1 may be FR-4, and its length, width and thickness may be 50 mm, 50 mm and 0.6 mm respectively. The metal trunk 2 and the metal branches 3 are metamaterials made of metal, such as copper, and their thickness may be about 35 μm. The maximum length and maximum width of the electromagnetic lens working unit formed by the metal trunk 2 and the metal branches 3 may be 29.4 mm respectively.

[0038] Please refer to the combination Figure 2The length of the metal trunk 2 is 29.40±0.05cm, the length L1 of the first branch 31 and the second branch 32 is 6.20±0.05cm, the length L2 of the third branch 33 is 3.2±0.05cm, the length L3 of the fourth branch 34 is 3.20±0.05cm, the length L4 of the fifth branch 35 is 2.20±0.05cm, the length L5 of the extension 341 is 0.9±0.05cm, their width is 0.4±0.05cm, the spacing d1 between the first branch 31 and the second branch 32 is 1.5±0.05cm, and the spacing d2 between the second branch 32 and the third branch 33 is 2±0.05cm.

[0039] Preferably, the length of the metal trunk 2 is 29.40±0.02cm, the length L1 of the first branch 31 and the second branch 32 is 6.20±0.02cm, the length L2 of the third branch 33 is 3.20±0.02cm, the length L3 of the fourth branch 34 is 3.20±0.02cm, the length L4 of the fifth branch 35 is 2.20±0.02cm, the length L5 of the extension 341 is 0.9±0.02cm, and their widths are 0.4±0.02cm respectively. The spacing d1 between the first branch 31 and the second branch 32 is 1.5±0.02cm, and the spacing d2 between the second branch 32 and the third branch 33 is 2±0.02cm.

[0040] Preferably, the length of the metal trunk 2 is 29.40±0.01cm, the length L1 of the first branch 31 and the second branch 32 is 6.20±0.01cm, the length L2 of the third branch 33 is 3.20±0.01cm, the length L3 of the fourth branch 34 is 3.20±0.01cm, the length L4 of the fifth branch 35 is 2.20±0.01cm, the length L5 of the extension 341 is 0.9±0.01cm, and their widths are 0.4±0.01cm respectively. The spacing d1 between the first branch 31 and the second branch 32 is 1.5±0.01cm, and the spacing d2 between the second branch 32 and the third branch 33 is 2±0.01cm.

[0041] The electric field intensity generated by the present invention is greater than that of the existing SSR at the same frequency by optimizing the shape of the electromagnetic lens and designing a reasonable size.

[0042] Example 1

[0043] The shape of the metamaterial electromagnetic lens in this embodiment is as follows Figure 2As shown, the copper with a thickness of 35 μm is printed on the surface of FR-4 medium, and the size is 29.4×29.4×0.035 mm. The length of the metal trunk 2 is 29.40 cm, the length L1 of the first branch 31 and the second branch 32 is 6.20 cm, the length L2 of the third branch 33 is 3.20 cm, the length L3 of the fourth branch 34 is 3.20 cm, the length L4 of the fifth branch 35 is 2.20 cm, the length L5 of the extension 341 is 0.9 cm, and their widths are 0.4 cm respectively. The spacing d1 between the first branch 31 and the second branch 32 is 1.5 cm, and the spacing d2 between the second branch 32 and the third branch 33 is 2 cm.

[0044] The S parameters and important parameters of the metamaterial electromagnetic lens of this embodiment are obtained by HFSS simulation. Figure 4 The S parameter amplitude of the metamaterial electromagnetic lens of this embodiment is shown.

[0045] The S parameter phase curve of the metamaterial electromagnetic lens of this embodiment is as follows: Figure 5 It can be seen that the working area of ​​the electromagnetic lens unit of an embodiment of the present disclosure is near the frequency of 1.9 GHz. In this area, the phase changes drastically, and negative relative permittivity, negative magnetic permeability and negative refractive properties begin to appear. The parameters are imported into MATLAB to solve the key parameters.

[0046] like Figure 6a-6d The relative dielectric constant, magnetic permeability, equivalent impedance and refractive index of the metamaterial electromagnetic lens of this embodiment are shown respectively. It can be seen that the "spider web" type electromagnetic lens also begins to show negative refraction and negative magnetic permeability characteristics at a frequency of about 1.9 GHz.

[0047] The HFSS simulation software can also display the surface electric field size of the metamaterial. Figure 7a-7c The electric field strength at 1 GHz, 2.45 GHz and 4 GHz is shown. The color indicates the electric field strength. The redder the color, the stronger the electric field, and the bluer the color, the weaker the electric field. At 1 GHz, since this is not the characteristic region of the metamaterial, Figure 7a It can be seen that the electric field induced by the metamaterial is weak and its effect is small. At 4 GHz, although the metamaterial is in the working area, its negative refraction effect is reduced. Figure 7c It can be seen that the induced electric field is also small. At 2.45GHz, within the working area, Figure 7b It can be seen that the induced electric field is the strongest and the metamaterial works strongly, which also proves the effectiveness of the designed metamaterial.

[0048] Comparative Example

[0049] The widely used electromagnetic lens at present is the classic split ring resonator (SSR) electromagnetic lens unit designed based on the S parameter extraction method. It is a bidirectional open resonator ring. By modeling it, the S parameters of the SSR unit are first derived. The HFSS simulation software simulates the S parameters of the SSR unit. The S11 and S21 parameters are as follows Figure 8 As shown in Figure 2, it can be seen that the structure undergoes a dramatic change near the frequency of 9.5 GHz, which is its working area.

[0050] The relative dielectric constant ε, magnetic permeability μ, equivalent impedance Z and refractive index n are calculated using S parameters, such as Figures 9a-9d As shown. It can be seen that it exhibits negative refraction and negative magnetic permeability characteristics near the working frequency of 9.5GHz. It can be seen that the negative refraction effect of the current SSR electromagnetic lens unit is not particularly good, and the focusing effect is not particularly ideal.

[0051] In the description of this specification, the description with reference to the terms "some embodiments", "optionally", "further" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0052] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A metamaterial electromagnetic lens, characterized in that: The invention comprises a substrate and four metal trunks (2) formed on the substrate and made of a metamaterial, and metal branches (3) respectively arranged at two ends of each metal trunk (2), wherein the four metal trunks (2) intersect at a first intersection (J1), the first intersection (J1) being the midpoint of each metal trunk (2), and each metal branch (3) comprises: A first branch (31) is vertically arranged at the end of the metal trunk (2), and the metal trunk (2) and the first branch (31) intersect at the midpoint of the first branch (31); a second branch (32), arranged between the first intersection point (J1) and the first branch (31), perpendicular to the metal trunk (2) and intersecting at a second intersection point (J2), wherein the second intersection point (J2) is the midpoint of the second branch (32); A third branch (33) is arranged between the first intersection (J1) and the second branch (32), is perpendicular to the metal trunk (2) and intersects at a third intersection (J3), and the third intersection (J3) is the midpoint of the third branch (33); Two fourth branches (34) are symmetrically arranged on both sides of the metal trunk (2), and the two fourth branches (34) respectively intersect with two ends of the first branch (31) and two ends of the second branch (32); Two fifth branches (35) are symmetrically arranged on both sides of the metal trunk (2), and extend from the third branch (33) toward the first intersection (J1).

2. The metamaterial electromagnetic lens according to claim 1, characterized in that: The two fourth branches (34) are respectively parallel to the metal trunk (2), and the two fourth branches (34) respectively extend from the two ends of the second branch (32) in a direction away from the first intersection (J1) and intersect with the two ends of the first branch (31), and cross the first branch (31) to form an extension portion (341).

3. The metamaterial electromagnetic lens according to claim 1, characterized in that: The two fifth branches (35) are parallel to the metal trunk (2).

4. The metamaterial electromagnetic lens according to any one of claims 1 to 3, characterized in that: The length of the metal trunk (2) is 29.40±0.05cm, the length L1 of the first branch (31) and the second branch (32) is 6.20±0.05cm, the length L2 of the third branch (33) is 3.2±0.05cm, the length L3 of the fourth branch (34) is 3.20±0.05cm, the length L4 of the fifth branch (35) is 2.20±0.05cm, the length L5 of the extension (341) is 0.9±0.05cm, their width is 0.4±0.05cm, the spacing d1 between the first branch (31) and the second branch (32) is 1.5±0.05cm, and the spacing d2 between the second branch (32) and the third branch (33) is 2±0.05cm.

5. The metamaterial electromagnetic lens according to claim 4, characterized in that: The length of the metal trunk (2) is 29.40±0.02 cm, the length L1 of the first branch (31) and the second branch (32) is 6.20±0.02 cm, the length L2 of the third branch (33) is 3.20±0.02 cm, the length L3 of the fourth branch (34) is 3.20±0.02 cm, the length L4 of the fifth branch (35) is 2.20±0.02 cm, the length L5 of the extension (341) is 0.9±0.02 cm, their width is 0.4±0.02 cm, the spacing d1 between the first branch (31) and the second branch (32) is 1.5±0.02 cm, and the spacing d2 between the second branch (32) and the third branch (33) is 2±0.02 cm.

6. The metamaterial electromagnetic lens according to claim 5, characterized in that: The length of the metal trunk (2) is 29.40±0.01cm, the length L1 of the first branch (31) and the second branch (32) is 6.20±0.01cm, the length L2 of the third branch (33) is 3.20±0.01cm, the length L3 of the fourth branch (34) is 3.20±0.01cm, the length L4 of the fifth branch (35) is 2.20±0.01cm, the length L5 of the extension (341) is 0.9±0.01cm, and their width is 0.4±0.01cm. The spacing d1 between the first branch (31) and the second branch (32) is 1.5±0.01cm, and the spacing d2 between the second branch (32) and the third branch (33) is 2±0.01cm.

7. The metamaterial electromagnetic lens according to claim 1, characterized in that: The substrate is a FR-4 board, and the length, width and thickness of the substrate are 50 mm, 50 mm and 0.6 mm respectively.

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