Conformal lightweight dual-polarization metasurface

Abstract

A metasurface unit sequentially comprises an outer skin, a first dielectric plate, a foam layer and a second dielectric plate from outside to inside, and the metasurface unit comprises a first dipole patch and a second dipole patch which are arranged on the lower surface of the first dielectric plate. Through arrangement of the planar micro-strip inductor on the upper surface of the first dielectric plate and positive and negative electrodes of the PIN tubes on the dipole patch, multi-path series direct current feed can be realized, and the number of the PIN tubes on each path of series direct current feed is the same. According to the invention, the antenna has the conformal capability, is light in weight, and can change the feed mode of the array plane through the special structure of the metasurface unit by flexibly controlling the inductance connection mode between the units. Through the feed mode, the metasurface array can still realize a good wave beam deflection function, and the application scene of the metasurface is greatly expanded.

Description

Technical Field

[0001] This invention belongs to the field of artificial electromagnetic metamaterials technology, specifically relating to a conformal lightweight dual-polarized metasurface. Background Art

[0002] Electromagnetic metasurfaces are artificial two-dimensional material structures that have attracted widespread attention due to their ability to manipulate electromagnetic waves. Currently, most research on metasurfaces focuses on single-polarization and single-cell controlled metasurface arrays. To adapt to more complex and variable communication environments and different assembly scenarios, research on conformal and lightweight dual-polarization metasurface arrays is of high research value. Firstly, conformality and lightweight design ensure that metasurfaces can be assembled and used on complex structures; secondly, dual polarization can improve the usability of metasurfaces and meet the need to fully utilize electromagnetic signals.

[0003] However, most existing metasurface designs involve independently feeding the cells on the metasurface. Research on tunable metasurfaces involving coplanarity and dual polarization is limited. Furthermore, existing tunable metasurface designs require complex power supply wiring, control circuits, and drive circuits, resulting in significant overall design complexity. Existing coplanar metasurfaces utilize a large number of diodes and require inductors to reduce inter-cell interference, which greatly increases the cost of the metasurface. Summary of the Invention

[0004] Purpose of the invention / Technical problem This invention addresses the technical problems existing in the prior art by proposing a conformal, lightweight, dual-polarization metasurface. This metasurface possesses conformal capability and is lightweight. Through the special structure of the metasurface unit, the feeding method of the array can be changed by flexibly controlling the inductive connection between control units. With this feeding mode, the metasurface array can still achieve good beam deflection functionality, greatly expanding the application scenarios of metasurfaces.

[0005] Technical Solution: To achieve the above-mentioned technical objectives, the present invention provides the following technical solution: a conformal lightweight dual-polarized metasurface, comprising multiple metasurface units arranged in an array periodically, wherein each metasurface unit comprises, from the outside to the inside, an outer skin, a first dielectric plate, a foam layer, and a second dielectric plate. The upper and lower surfaces of the first dielectric plate are respectively provided with a first metal layer and a second metal layer, and the upper surface of the second dielectric plate is further provided with a third metal layer, wherein: The second metal layer consists of four sets of triangular metal patches arranged symmetrically at the center. Each set of triangular metal patches includes a metal patch of an isosceles right triangle with two right-angled sides that are parallel to each other. The two sets of triangular metal patches on the left and right sides of the metasurface unit can be combined with the corresponding sets of triangular metal patches of the adjacent metasurface units on the left and right sides to form two isosceles right-angled triangular metal patches with parallel and opposite bases, referred to as the first dipole patch; a PIN tube is also provided between the two isosceles right-angled triangular metal patches with parallel and opposite bases. The two sets of triangular metal patches on the upper and lower sides of the metasurface unit can be combined with the corresponding sets of triangular metal patches of the adjacent metasurface units on the upper and lower sides to form two isosceles right-angled triangular metal patches with parallel and opposite bases, referred to as the second dipole patch; a PIN tube is also provided between the two isosceles right-angled triangular metal patches with parallel and opposite bases. The first metal layer is provided with a planar microstrip inductor, and the two ends of the planar microstrip inductor are connected to the first dipole patch and the second dipole patch respectively through metallized vias provided on the first dielectric substrate; The connection method of the planar microstrip inductor and the positive and negative polarity settings of the PIN tubes can ensure the realization of multiple series DC power supplies, and the number of PIN tubes on each series DC power supply is the same.

[0006] Preferably, the multi-channel current feed line is a zigzag segment with a 90° bend and at least one bend.

[0007] Preferably, the period of the metasurface unit is 10mm-12mm, and the base of the isosceles right-angled triangular metal patch is 7-9mm long and the height is 4.5-6mm.

[0008] Preferably, the first dielectric substrate is made of PET material with a thickness of 0.05-0.1mm.

[0009] Preferably, the outer skin is made of glass fiber with a dielectric constant of 3-4 and a thickness of 0.1-0.5 mm.

[0010] Preferably, the thickness of the foam layer is 2-3 mm.

[0011] Preferably, the second dielectric substrate is made of PET material with a thickness of 0.05-0.1mm.

[0012] Beneficial Effects: Compared to existing technologies, the conformal and lightweight dual-polarization metasurface structure designed in this invention has a wide operating bandwidth covering the entire X-band. It can achieve 1-bit phase modulation and amplitude modulation of two polarized electromagnetic waves. Compared to existing metasurface structures, this metasurface structure does not require power supply through through-holes, avoiding complex power supply network designs and reducing the complexity of metasurface design. Furthermore, due to its light weight and conformal nature, this structure has more application scenarios compared to other metasurfaces.

[0013] To meet the requirements of the coplanar design of dual-polarized metasurfaces, the metasurface array needs to satisfy DC feeding and RF isolation. Both technical requirements allow for flexible array DC feeding methods by connecting units through planar microstrip inductors. Furthermore, its inductive properties can eliminate radio frequency coupling effects between units. This scheme can greatly expand the capabilities of this metasurface. The application scenarios enable it to maintain good working performance even in complex curved surface environments. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the conformal lightweight dual-polarized metasurface described in this invention.

[0015] Figure 2 This is a schematic diagram of the structure of the metasurface unit described in this invention.

[0016] Figure 3 This is a schematic diagram of the series DC power supply of the dual-polarized metasurface in Embodiment 1 of the present invention.

[0017] Figure 4 This is the amplitude response of the metasurface unit when the PIN tube is switched on in an embodiment of the present invention.

[0018] Figure 5 This is the phase response of the unit when the PIN tube is switched on / off according to an embodiment of the present invention.

[0019] Figure 6 This is the amplitude response of the unit when the PIN tube is in a micro-conduction state according to an embodiment of the present invention.

[0020] In the figure, the outer skin is 1, the first metal layer is 2, the first dielectric layer is 3, the second metal layer is 4, the foam layer is 5, the third metal layer is 6, the second dielectric layer is 7, the planar microstrip is 8, the isosceles right-angled triangular metal patch is 9, the PIN tube is 10, and the series DC power supply is 11. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention. Unless otherwise specifically stated, the relative arrangement, expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0022] For ease of description, spatial relative terms such as "above," "over," "on the upper surface of," "above," etc., are used here to describe the spatial positional relationship of a device or feature as shown in the figure with other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation besides the orientation of the device as described in the figure. For example, if the device in the figure is inverted, a device described as "above" or "above" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations).

[0023] like Figure 1-3 As shown, the conformal lightweight dual-polarized metasurface of the present invention includes multiple metasurface units arranged in a periodic array. The period size of the metasurface unit is 10mm-12mm. Each metasurface unit, from the outside to the inside, includes an outer skin, a first dielectric plate, a foam layer, and a second dielectric plate. The upper and lower surfaces of the first dielectric plate are respectively provided with a first metal layer and a second metal layer. The upper surface of the second dielectric plate is further provided with a third metal layer. (1) The first layer of the metasurface structure is an outer skin structure, which can prevent water vapor from entering the interior of the metasurface structure and play a protective role. The outer skin material is a glass fiber structure with a dielectric constant of 3-4 and a thickness of 0.1-0.5 mm. The thinner outer skin structure can effectively protect the metasurface structure while reducing the weight of the metasurface structure.

[0024] (2) The first dielectric substrate is divided into a first metal layer, a first dielectric layer and a second metal layer from top to bottom.

[0025] The first dielectric layer is made of flexible PET material with a thickness of 0.05-0.1mm. It is malleable and can be wrapped around complex structures such as columns and cones.

[0026] (3) The first metal layer is connected to the planar microstrip inductor at one end through a metallized via, and to the dipole patch at the other end. The first dipole patch and the second dipole patch are connected together through the first metal layer, the metallized via, and the planar microstrip inductor.

[0027] (4) The metasurface unit is composed of a first dipole patch and a second dipole patch. The metasurface array is composed of metasurface units arranged periodically. The metasurface units and the left and right metasurface units can be combined to form the first dipole patch, and the top and bottom metasurface units can be combined to form the second dipole patch. This structural design method can effectively reduce the unit size while ensuring the performance of the metasurface unit.

[0028] (5) Both the first and second dipole patches are composed of a pair of isosceles triangular patches with a base length of 7-9 mm and a height of 4.5-6 mm. The first and second dipole patches have identical dimensions and structures, thus ensuring the consistency of the metasurface's response to horizontal and vertical polarized waves. The vertical polarized wave can be controlled by adjusting the state of the PIN diode on the first dipole patch, and the horizontal polarized wave can be controlled by adjusting the state of the PIN diode on the second dipole patch.

[0029] (6) The first and second dipole patches are interconnected via a planar microstrip inductor. The planar microstrip inductor can block the cross-polarization current between the first and second dipole patches, preventing the deterioration of the common-polarization reflection amplitude. It also serves as a DC power supply. Overall, the planar microstrip inductor can pass DC and block AC. The planar microstrip inductor can ensure the stability of the electrical performance of the metasurface structure while avoiding the use of inductor components, thus reducing the cost of the metasurface structure.

[0030] (7) The first dielectric substrate and the foam layer are laminated together. The foam layer and the second dielectric substrate are laminated together. The thickness of the foam layer is 2mm-3mm, which provides structural support while reducing the overall weight of the metasurface structure. The foam layer is easy to process and has low cost, and can be processed quickly according to the actual application scenario of the metasurface.

[0031] (8) The second dielectric substrate is made of flexible PET material, and the upper layer is a third metal layer. The third metal layer can ensure the reflectivity of the metasurface array, and the thinner flexible dielectric substrate can ensure the ductility of the metasurface array.

[0032] The metasurface array is composed of the basic metasurface units shown in the figure. The dipole patch containing the PIN diodes along the Y-axis is the first dipole patch, and the dipole patch containing the PIN diodes along the X-axis is the second dipole patch. The first dipole patch has a positive terminal below and a negative terminal above the PIN diodes, while the second dipole patch has a positive terminal to the right and a negative terminal to the left of the PIN diodes. Microstrip planar inductors enable interconnection between the dipole patches, providing series DC power supply. Furthermore, the planar microstrip inductors provide RF isolation between the dipole patches, ensuring the array's performance. Example

[0033] like Figure 3 As shown, in this embodiment, the metasurface uses a 45° power supply method to achieve overall power supply to the array surface based on its structural characteristics, and the series DC feed line is a 90° broken line segment. Other methods, such as planar microstrip inductor connection and PIN diode polarity orientation, can also achieve the functionality of this invention.

[0034] Due to the unique structure of the metasurface units, the units are interconnected via microstrip inductors at a 45° angle. Therefore, the DC feeding of the metasurface no longer employs traditional row- or column-controlled feeding schemes. This metasurface array can change its feeding method by flexibly controlling the inductor connections between units. Even with this feeding mode, the metasurface array can still achieve good beam deflection capabilities.

[0035] like Figure 4-6 As shown, when the current through the diode is 0mA, the diode on the metasurface is in the off state, and the reflection amplitude is within -2dB; when the current through the metasurface is 5mA, the diode on the metasurface is in the on state, and the reflection amplitude is within -1dB; and the phase difference between the two states is within 180°±30°. When the current through the diode is 10uA, the metasurface switches to an absorbing state, achieving an absorption effect within -14dB across the entire X-band.

[0036] The above description is only a partial embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A conformal, lightweight, dual-polarized metasurface, characterized in that: The system comprises multiple metasurface units arranged in a periodic array. From the outside to the inside, each metasurface unit includes an outer skin, a first dielectric plate, a foam layer, and a second dielectric plate. The upper and lower surfaces of the first dielectric plate are respectively provided with a first metal layer and a second metal layer. The upper surface of the second dielectric plate is further provided with a third metal layer. The second metal layer consists of four sets of triangular metal patches arranged symmetrically at the center. Each set of triangular metal patches includes a metal patch of an isosceles right triangle with two right-angled sides that are parallel to each other. The two sets of triangular metal patches on the left and right sides of the metasurface unit can be combined with the corresponding sets of triangular metal patches of the adjacent metasurface units on the left and right sides to form two isosceles right-angled triangular metal patches with parallel and opposite bases, referred to as the first dipole patch; a PIN tube is also provided between the two isosceles right-angled triangular metal patches with parallel and opposite bases. The two sets of triangular metal patches on the upper and lower sides of the metasurface unit can be combined with the corresponding sets of triangular metal patches of the adjacent metasurface units on the upper and lower sides to form two isosceles right-angled triangular metal patches with parallel and opposite bases, referred to as the second dipole patch; a PIN tube is also provided between the two isosceles right-angled triangular metal patches with parallel and opposite bases. The first metal layer is provided with a planar microstrip inductor, and the two ends of the planar microstrip inductor are connected to the first dipole patch and the second dipole patch respectively through metallized vias provided on the first dielectric substrate; The connection method of the planar microstrip inductor and the positive and negative polarity settings of the PIN tubes can ensure the realization of multiple series DC power supplies, and the number of PIN tubes on each series DC power supply is the same.

2. The conformal lightweight dual-polarized metasurface according to claim 1, characterized in that: The multi-channel current feed line is a zigzag segment with a 90° bend and at least one bend.

3. The conformal lightweight dual-polarized metasurface according to claim 1, characterized in that: The period of the metasurface unit is 10mm-12mm, and the base of the isosceles right-angled triangular metal patch is 7-9mm long and the height is 4.5-6mm.

4. The conformal lightweight dual-polarized metasurface according to claim 1, characterized in that: The first dielectric substrate is made of PET material with a thickness of 0.05-0.1mm.

5. The conformal lightweight dual-polarized metasurface according to claim 1, characterized in that: The outer skin is made of glass fiber with a dielectric constant of 3-4 and a thickness of 0.1-0.5 mm.

6. The conformal lightweight dual-polarized metasurface according to claim 1, characterized in that: The thickness of the foam layer is 2-3 mm.

7. The conformal lightweight dual-polarized metasurface according to claim 1, characterized in that: The second dielectric substrate is made of PET material with a thickness of 0.05-0.1mm.

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