A single-layer dual-frequency huygens super-surface unit

Abstract

The application discloses a single-layer double-frequency Huygens super surface unit, belonging to the field of artificial electromagnetic. The unit is composed of a double independent mirror symmetry structure in xy plane and a dielectric substrate, wherein the first metal sheet, the second metal sheet, the third metal sheet and the mirror metal sheets of the three respectively form a first mirror symmetry structure, the fourth metal sheet and the fifth metal sheet and the mirror metal sheets of the two respectively form a second mirror symmetry structure, and all the metal sheet structures are rectangular strip structures. The super surface unit of the application only induces magnetic current through the upper and lower metal sheets, has no other magnetic elements or via structures, and has the characteristics of simple structure, compactness and easy processing. The working frequency of the application is 32GHz and 38.5GHz respectively, has high electromagnetic wave transmittance and nearly 360º electromagnetic wave transmission phase control, can respond to two different frequency incident electromagnetic waves respectively, realizes independent electromagnetic control function, and increases electromagnetic channel capacity.

Description

Technical Field

[0001] This invention belongs to the field of artificial electromagnetics and relates to a single-layer dual-frequency Huygens metasurface unit. Background Technology

[0002] Metasurfaces are two-dimensional artificial electromagnetic materials composed of periodic or aperiodic subwavelength-sized structural units, capable of precisely controlling the amplitude, phase, polarization, and other characteristics of electromagnetic waves. In recent years, metasurfaces have achieved excellent electromagnetic performance in numerous applications, such as focusing, polarization conversion, and holographic imaging. With the rapid development of technologies such as 5G systems and millimeter-wave radar, the demand for multi-band, multi-polarization, and highly integrated electromagnetic control devices is increasing. However, traditional dual-frequency metasurfaces often employ multi-layer stacked structures, leading to increased device profiles and problems such as frequency band shift and decreased polarization isolation caused by interlayer coupling. Single-layer structures often employ complex unit structures, resulting in high fabrication difficulty and reduced yield. Huygens metasurfaces possess low profile and high transmittance electromagnetic properties, making them suitable for electromagnetic systems. However, current research and applications of Huygens metasurfaces mainly focus on single-frequency applications, and most unit structures are quite complex. Therefore, designing a Huygens metasurface unit with dual-frequency, high transmittance, and simple structure has significant practical and engineering value. Summary of the Invention

[0003] In view of this, the object of the present invention is to provide a single-layer dual-frequency Huygens metasurface unit.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] A single-layer dual-frequency Huygens metasurface unit adopts a dual independent mirror symmetry structure in the xy plane. The first metal sheet (1), the second metal sheet (2), the third metal sheet (3) and their respective mirror metal sheets form a first mirror symmetry structure, and the fourth metal sheet (4) and the fifth metal sheet (5) and their respective mirror metal sheets form a second mirror symmetry structure. The metasurface unit is a planar structure, placed horizontally along the xy plane, and adopts a single-layer dielectric substrate (6).

[0006] Optionally, the dielectric substrate material is F4B, with a dielectric constant of 2.2, a loss tangent of 0.001, and a thickness of 1.5 mm.

[0007] Optionally, the period of the metasurface unit is 5 mm, and the distance between all metal sheets and the boundary of the dielectric substrate (6) is the same, which is 0.1 mm.

[0008] Optionally, the first metal sheet (1) and its mirror metal sheet, the fourth metal sheet (4) and its mirror metal sheet are placed along the x-axis and y-axis directions respectively, located on the top layer of the dielectric substrate (6); the second metal sheet (2) and the third metal sheet (3) and their respective mirror metal sheets are placed along the x-axis direction, located on both sides of the bottom layer of the dielectric substrate (6); the fifth metal sheet (5) and its mirror metal sheet are placed along the y-axis direction, located on the bottom layer of the dielectric substrate (6).

[0009] Optionally, the first metal sheet (1), the second metal sheet (2), and the third metal sheet (3) have the same width, and the second metal sheet (2) and the third metal sheet (3) have the same length and are half the length of the first metal sheet (1).

[0010] Optionally, the fourth metal sheet (4) and the fifth metal sheet (5) have the same length and width, and there is a partial overlap between the upper and lower metal sheets.

[0011] Optionally, the Huygens metasurface unit does not have additional magnetic elements or via structures. It induces magnetic current by changing the structural parameters of the upper and lower metal sheets. The magnetic current interacts with the surface current of the metal sheets, thereby forming electromagnetic resonance and achieving high transmission of electromagnetic waves.

[0012] Optionally, the Huygens metasurface unit can change the amplitude and phase of the x-polarized transmitted wave by changing the length of the first metal sheet (1). At the first operating frequency of 32 GHz, the transmission amplitude of the x-polarized transmitted wave is greater than 0.9, and the transmission phase of 323º can be controlled. By changing the length of the overlapping area of ​​the fourth metal sheet (4) and the fifth metal sheet (5), the amplitude and phase of the y-polarized transmitted wave can be changed. At the second operating frequency of 38.5 GHz, the transmission amplitude of the y-polarized transmitted wave is greater than 0.88, and the transmission phase of 324º can be controlled.

[0013] The beneficial effects of this invention are as follows:

[0014] (1) Compared with multi-layer stacked dual-frequency metasurface units, the dual-frequency metasurface unit of the present invention has the characteristic of low profile; compared with most single-layer dual-frequency metasurface units, it has the characteristics of simple structure and easy processing.

[0015] (2) The dual-frequency Huygens metasurface unit of the present invention has high electromagnetic wave transmittance and wide transmission electromagnetic wave phase modulation. At the hardware level, there are only dielectric substrates and metal structures, without other magnetic components or via structures. The magnetic current is induced by the upper and lower metal sheets, and the interaction between the magnetic current and the surface current achieves electromagnetic resonance.

[0016] (3) The dual-frequency Huygens metasurface unit of the present invention uses an F4B dielectric substrate with a thickness of 1.5mm, which is relatively low in cost among high-frequency dielectric substrates, and takes into account the requirements of low loss, miniaturization and integration.

[0017] (4) The dual-frequency Huygens metasurface unit of the present invention can respond to two different incident electromagnetic waves, realize independent electromagnetic control function, increase electromagnetic channel capacity, and realize electromagnetic control function at 32GHz and 38.5GHz respectively. At present, most Huygens metasurfaces only realize the function at a single frequency point. The present invention expands the dual-frequency application of Huygens metasurfaces. Attached Figure Description

[0018] To more clearly illustrate the purpose, advantages, and technical solutions of this invention, the accompanying drawings required for this invention will be described below. It should be understood that the following drawings should not be regarded as a limitation on the scope of this invention.

[0019] Figure 1 A schematic diagram of the three-dimensional structure of a single-layer dual-frequency Huygens metasurface unit;

[0020] Figure 2 A schematic diagram of the upper metal structure and parameters of a single-layer dual-frequency Huygens metasurface unit;

[0021] Figure 3 A schematic diagram of the lower metal structure and parameters of a single-layer dual-frequency Huygens metasurface unit;

[0022] Figure 4 Transmission amplitude and phase diagrams for a single-layer dual-frequency Huygens metasurface unit at 32 GHz under x-polarization;

[0023] Figure 5 The y-polarization transmission amplitude and transmission phase diagram of a single-layer dual-frequency Huygens metasurface unit at 38.5 GHz;

[0024] Figure 6 Phase distribution diagram of a double-focal metasurface composed of single-layer dual-frequency Huygens metasurface units;

[0025] Figure 7 Phase distribution diagram of a single-focus metasurface composed of single-layer dual-frequency Huygens metasurface units;

[0026] Figure 8 A schematic diagram of the top layer of a focusing metasurface composed of single-layer dual-frequency Huygens metasurface units;

[0027] Figure 9 A schematic diagram of the bottom layer of a focusing metasurface composed of single-layer dual-frequency Huygens metasurface units;

[0028] Figure 10The electric field distribution of the focused metasurface under incident x-polarized waves at 32 GHz is shown.

[0029] Figure 11 The electric field distribution of the focused metasurface under incident y-polarized wave at 38.5 GHz is shown.

[0030] Reference numerals: 1-First metal sheet, 2-Second metal sheet, 3-Third metal sheet, 4-Third metal sheet, 5-Fifth metal sheet, 6-Dielectric substrate. Detailed Implementation

[0031] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer from the following description. It should be noted that the drawings are in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the present invention. Please refer to the accompanying drawings to make the objectives, features, and advantages of the present invention more apparent and understandable.

[0032] This invention provides a single-layer dual-frequency Huygens metasurface unit, the specific implementation of which is as follows:

[0033] See Figure 1 The single-layer dual-frequency Huygens metasurface unit adopts a dual independent mirror symmetry structure in the xy plane. The first metal sheet (1), the second metal sheet (2), the third metal sheet (3) and their respective mirror metal sheets form the first mirror symmetry structure, and the fourth metal sheet (4) and the fifth metal sheet (5) and their respective mirror metal sheets form the second mirror symmetry structure. The metasurface unit is a planar structure, placed horizontally along the xy plane, and adopts a single-layer dielectric substrate (6).

[0034] See Figures 2-3The first metal sheet (1) and its mirror metal sheet, and the fourth metal sheet (4) and its mirror metal sheet are placed along the x-axis and y-axis directions respectively, located on the top layer of the dielectric substrate (6). The second metal sheet (2) and the third metal sheet (3) and their respective mirror metal sheets are placed along the x-axis direction, located on both sides of the bottom layer of the dielectric substrate (6); the fifth metal sheet (5) and its mirror metal sheet are placed along the y-axis direction, located on the bottom layer of the dielectric substrate (6). The first metal sheet (1), the second metal sheet (2), and the third metal sheet (3) have the same width W1, which is 0.1 mm. The second metal sheet (2) and the third metal sheet (3) have the same length, which is half the length of the first metal sheet (1). The fourth metal sheet (4) and the fifth metal sheet (5) have the same length and width. There is a partial overlap between the upper and lower metal sheets. The width W2 is 0.08 mm, the fixed length L2 is 1.9 mm, and the length of the overlap area is twice the parameter d. The distance between all metal sheets and the boundary of the dielectric substrate (6) is the same, which is 0.1 mm. The Huygens metasurface unit does not have any additional magnetic elements or via structures. It induces magnetic current by changing the structural parameters of the upper and lower metal sheets. The magnetic current interacts with the surface current of the metal sheets, thereby forming electromagnetic resonance and achieving high transmission of incident electromagnetic waves.

[0035] The first operating frequency of the single-layer dual-frequency Huygens metasurface unit of the present invention is 32 GHz, the second operating frequency is 38.5 GHz, the period P of the unit is a subwavelength, i.e., 5 mm; the dielectric substrate material is F4B, the dielectric constant is 2.2, the loss tangent is 0.001, and the thickness h is 1.5 mm.

[0036] The single-layer Huygens metasurface unit of the present invention can respond to x-polarized incident waves at 32 GHz and y-polarized incident waves at 38.5 GHz respectively, thereby changing the amplitude and phase of the transmitted electromagnetic waves and independently realizing electromagnetic control functions at 32 GHz and 38.5 GHz. By changing the length of the first metal sheet (1), the metasurface unit of the present invention can change the amplitude and phase of the x-polarized transmitted waves. At the first operating frequency of 32 GHz, the transmission amplitude of the x-polarized transmitted waves is greater than 0.9, and the transmission phase of 323º can be controlled. By changing the length of the overlapping area of ​​the fourth metal sheet (4) and the fifth metal sheet (5), the amplitude and phase of the y-polarized transmitted waves can be changed. At the second operating frequency of 38.5 GHz, the transmission amplitude of the y-polarized transmitted waves is greater than 0.88, and the transmission phase of 324º can be controlled.

[0037] Figure 4This is a graph showing the transmission amplitude and phase of x-polarized transmitted waves at 32 GHz for a single-layer dual-frequency Huygens metasurface unit as a function of the unit parameter L1. Simulation results show that when the metal sheet length parameter L1 varies from 0.8 mm to 5 mm, the transmission amplitude of the x-polarized wave is greater than 0.9, and the transmission phase at 323º can be tuned.

[0038] Figure 5 This is a graph showing the transmission amplitude and phase of a y-polarized transmitted wave at 38.5 GHz using a single-layer dual-frequency Huygens metasurface unit as a function of the unit parameter d. Simulation results show that when the overlap parameter d of the upper and lower metal sheets varies from 0 mm to 2.2 mm, the transmission amplitude of the y-polarized wave is greater than 0.88, and the transmission phase at 324º can be tuned.

[0039] Figure 6 The phase distribution diagram is shown for a focusing metasurface composed of a single-layer dual-frequency Huygens metasurface unit. This metasurface achieves two focal points in a preset plane by controlling a 32 GHz x-polarized incident wave. The positions of the two focal points are (35, 65, 60) mm and (95, 65, 60) mm, respectively.

[0040] Figure 7 The phase distribution diagram is shown for a focusing metasurface composed of a single-layer dual-frequency Huygens metasurface unit. This metasurface achieves a single focal point in a preset plane by modulating a 38.5 GHz y-polarized incident wave, with the focal point located at (65, 65, 35) mm.

[0041] Figures 8-9 This is a structural diagram of the focusing metasurface composed of a single-layer dual-frequency Huygens metasurface unit according to the present invention. The metasurface consists of 25×25 units, with an overall size of 125mm×125mm×1.5mm. It can be seen that the arrangement of the metasurface units along the x-axis and along the y-axis is different, so that the metasurface responds to two incident electromagnetic waves of different frequencies, realizes independent electromagnetic control function, and increases the electromagnetic channel capacity.

[0042] Figure 10 This is an electric field distribution diagram of a focusing metasurface composed of a single-layer dual-frequency Huygens metasurface unit under 32GHz x-polarized wave incident light; two focal points are achieved in the xy plane at a distance of 60mm from the metasurface.

[0043] Figure 11 The electric field distribution diagram of the focusing metasurface composed of a single layer of dual-frequency Huygens metasurface units of the present invention is shown under the incident y-polarized wave of 38.5 GHz; a single focus is achieved in the xy plane 35 mm away from the metasurface.

[0044] The above descriptions are merely embodiments of this application and are not intended to limit the scope of this application. Those skilled in the art can derive related modifications and variations beyond those described herein by applying relevant principles and techniques. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A single-layer dual-frequency Huygens metasurface unit, characterized in that: The metasurface unit adopts a dual independent mirror symmetry structure in the xy plane. The first metal sheet (1), the second metal sheet (2), the third metal sheet (3) and their respective mirror metal sheets form the first mirror symmetry structure. The fourth metal sheet (4) and the fifth metal sheet (5) and their respective mirror metal sheets form the second mirror symmetry structure. The metasurface unit is a planar structure, placed horizontally along the xy plane, and uses a single-layer dielectric substrate (6).

2. The single-layer dual-frequency Huygens metasurface unit according to claim 1, characterized in that: The first metal sheet (1) and its mirror metal sheet, the fourth metal sheet (4) and its mirror metal sheet are placed along the x-axis and y-axis directions respectively, and are located on the top layer of the dielectric substrate (6); the second metal sheet (2) and the third metal sheet (3) and their respective mirror metal sheets are placed along the x-axis direction, and are located on both sides of the bottom layer of the dielectric substrate (6); the fifth metal sheet (5) and its mirror metal sheet are placed along the y-axis direction, and are located on the bottom layer of the dielectric substrate (6).

3. The single-layer dual-frequency Huygens metasurface unit according to claim 1, characterized in that: The first metal sheet (1), the second metal sheet (2), and the third metal sheet (3) have the same width. The second metal sheet (2) and the third metal sheet (3) have the same length and are half the length of the first metal sheet (1).

4. The single-layer dual-frequency Huygens metasurface unit according to claim 1, characterized in that: The fourth metal sheet (4) and the fifth metal sheet (5) have the same length and width, and there is a partial overlap between the upper and lower metal sheets.

5. A single-layer dual-frequency Huygens metasurface unit according to claim 1, characterized in that: The period of the metasurface unit is 5 mm; all metal sheets are 0.1 mm away from the boundary of the dielectric substrate (6).

6. The single-layer dual-frequency Huygens metasurface unit according to claim 1, characterized in that: The dielectric substrate material is F4B, with a dielectric constant of 2.2, a loss tangent of 0.001, and a thickness of 1.5 mm.

7. A single-layer dual-frequency Huygens metasurface unit according to claim 1, characterized in that: The Huygens metasurface unit described above can efficiently transmit electromagnetic waves. It does not have any additional magnetic elements or via structures. It induces magnetic current by changing the structural parameters of the upper and lower metal sheets. The magnetic current interacts with the surface current of the metal sheets, thereby forming electromagnetic resonance. This metasurface unit has no stacked or complex structure and has the characteristics of low profile and easy processing.

8. A single-layer dual-frequency Huygens metasurface unit according to claim 1, characterized in that: The Huygens metasurface unit changes the amplitude and phase of the x-polarized transmitted wave by changing the length of the first metal sheet (1). At the first operating frequency of 32 GHz, the transmission amplitude of the x-polarized transmitted wave is greater than 0.9, and the transmission phase of the x-polarized wave at 323º can be controlled. By changing the length of the overlapping area of ​​the fourth metal sheet (4) and the fifth metal sheet (5), the amplitude and phase of the y-polarized transmitted wave are changed. At the second operating frequency of 38.5 GHz, the transmission amplitude of the y-polarized transmitted wave is greater than 0.88, and the transmission phase of the y-polarized wave at 324º can be controlled.

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