Ultrathin transflective skin with conformal curved surface

Abstract

A metasurface unit is printed on a dielectric substrate by adopting a double-layer metal structure, a top-layer metal structure comprises a central cross-shaped metal patch, an edge square ring metal patch and rectangular metal patches on two sides, the central cross-shaped metal patch is placed at the central position of the dielectric substrate, and the edge square ring metal patch is placed at the central position of the dielectric substrate. The edge of the edge square ring metal patch coincides with the edge of the dielectric substrate, the rectangular metal patches on the two sides are placed between the central cross-shaped metal patch and the edge square ring metal patch and connected with the edge square ring metal patch, and a gap is reserved between the rectangular metal patches on the two sides and the central cross-shaped metal patch. PIN diodes are loaded at gaps between the rectangular metal patches on the two sides and the central cross-shaped metal patch; the bottom layer metal structure is obtained by rotating the top layer metal structure by 90 degrees according to the normal direction, and the top layer cross-shaped metal patch and the bottom layer cross-shaped metal patch are connected through a metal through hole. According to the invention, the self-adaptive switching wave transmission and reflection functions can be realized.

Description

Technical Field

[0001] The present invention relates to electromagnetic stealth technology, and in particular to an ultra-thin transflective integrated skin with a conformal curved surface. Background Art

[0002] Effective control and management of electromagnetic waves is crucial in modern communications and radar systems. While traditional metasurface technologies can achieve some degree of control over electromagnetic waves, most designs are passive, making it difficult to dynamically adjust their transmission and reflection properties. While some tunable metasurfaces exist, their tuning methods are complex, their response speeds are slow, and they often require complex circuitry or mechanical control. Furthermore, they struggle to meet the curvature requirements of stealth platforms. Summary of the Invention

[0003] The purpose of the present invention is to provide an ultra-thin transflective integrated skin with a conformal curved surface to solve the problems of slow response speed and difficulty in achieving compatibility between electromagnetic shielding and working signal transmission and reception.

[0004] The technical solution to achieve the purpose of the present invention is: a curved conformal ultra-thin transflective integrated skin, including a plurality of periodically arranged metasurface units, the metasurface units are printed on a dielectric substrate using a double-layer metal structure, including: a top metal structure, a bottom metal structure and a dielectric substrate, wherein:

[0005] The top metal structure is placed on the bottom of the dielectric substrate and includes a central cross-shaped metal patch, an edge square ring metal patch, and rectangular metal patches on both sides. The central cross-shaped metal patch is placed at the center of the dielectric substrate, the edge of the edge square ring metal patch coincides with the edge of the dielectric substrate, the rectangular metal patches on both sides are placed between the central cross-shaped metal patch and the edge square ring metal patch, connected to the edge square ring metal patches, leaving a gap with the central cross metal patch, and PIN diodes are loaded in the gap between the rectangular metal patches on both sides and the central cross-shaped metal patch; the bottom metal structure is placed on the bottom surface of the dielectric substrate and is obtained by rotating the top metal structure 90 degrees according to the normal direction. The top cross-shaped metal patch and the bottom cross-shaped metal patch are connected through metal through holes.

[0006] Furthermore, the dielectric substrate is made of Rogers 4350b.

[0007] Furthermore, when the top metal structure is used to weld diodes, the welding direction of each column of diodes remains consistent; when the bottom metal structure is used to weld diodes, the welding direction of each row of diodes remains consistent.

[0008] Furthermore, the metasurface units are electrically connected via edge square ring metal patches, forming a series feeding method.

[0009] Furthermore, by controlling the voltage switching state, a strong electromagnetic shielding effect in different frequency bands is achieved, which is compatible with normal communication signal transmission and reception. Specifically:

[0010] By controlling the voltage loading, the free-space equivalent impedance of the PIN diode is changed, thereby changing the electromagnetic response of the metasurface unit to the incident electromagnetic wave, thus achieving the reconfigurable function of the curved, conformal, ultra-thin, transflective integrated skin.

[0011] When a larger bias voltage is applied, the diode is in the on-state, and the surface impedance of the curved conformal ultra-thin transflective integrated skin changes from a high-resistance state to a low-resistance state, thereby realizing the regulation of the passband and stopband, wherein the low frequency is the stopband and the high frequency is the passband; when a smaller bias voltage is applied or no power is applied, the diode is in the off-state, and the surface impedance of the curved conformal ultra-thin transflective integrated skin changes from a low-resistance state to a high-resistance state, thereby realizing the regulation of the passband and stopband, wherein the high frequency is the stopband and the low frequency is the passband.

[0012] Furthermore, when the diode is in the cut-off state, the low frequency is in the wave-transmitting state and the high frequency is in the wave-reflecting state; when the diode is in the on state, the low frequency is in the wave-reflecting state and the high frequency is in the wave-transmitting state, wherein the wave-transmitting state is the communication state and the reflective state is the shielding state.

[0013] Compared with existing technologies, the present invention has the following significant advantages: 1) The reconfigurable transmissive and reflective metasurface units are periodically arranged, and the diodes are turned on or off by controlling the bias voltage across the diodes. This changes the impedance of the metasurface's surface structure, allowing the metasurface's wave-transmitting and reflective states to be switched between controllably and rapidly, achieving selectivity in the transmission and reflection of electromagnetic waves. 2) The use of an ultra-thin single-layer dielectric substrate, which is flexible and bendable, can conform to carriers of varying curvatures to accommodate the design requirements of actual stealth platforms. Therefore, it is suitable for various electromagnetic wave manipulation applications, such as electromagnetic compatibility and electromagnetic stealth, providing an efficient and flexible electromagnetic wave management solution. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 Schematic diagram of the metasurface unit structure;

[0015] Figure 2 Schematic diagram of the top structure of the metasurface array;

[0016] Figure 3 Schematic diagram of the underlying structure of the metasurface array;

[0017] Figure 4 Schematic diagram of the arrangement of the positive and negative electrodes of the diodes in the top structure of the metasurface array;

[0018] Figure 5 Schematic diagram of the arrangement of the positive and negative electrodes of the diodes in the underlying structure of the metasurface array;

[0019] Figure 6 is the S of the metasurface in two states 21 parameter diagram;

[0020] Figure 7 is the S of the metasurface in two states 11 parameter diagram;

[0021] Explanation of symbols:

[0022] 1-Center cross-shaped metal patch, 2-Edge square ring metal patch, 3-PIN diode, 4-Dielectric substrate, 5-Rectangular metal patches on both sides, 6-Metal through hole. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0024] The present invention discloses a curved conformal ultra-thin transflective integrated skin comprising a plurality of periodically arranged metasurface units, which are printed on a dielectric substrate using a double-layer metal structure. Figure 1 This is a structural diagram of the metasurface unit. The top metal structure is placed on the top layer of the dielectric substrate, and the bottom metal structure is placed on the bottom layer of the dielectric substrate.

[0025] like Figure 1 、 2 As shown, the top metal structure consists of a central cross-shaped metal patch 1, edge square ring metal patches 2, a PIN diode 3, a dielectric substrate 4, two rectangular metal patches 5, and metal vias 6. The central cross-shaped metal patch is placed at the center of the dielectric substrate, with the edges of the edge square ring metal patches coinciding with the edges of the dielectric substrate. The two rectangular metal patches are placed between the central cross-shaped metal patch and the edge square ring metal patches, connected to the edge square ring metal patches, and leaving a gap with the central cross metal patch. The PIN diode is loaded in the gap between the two rectangular metal patches and the central cross-shaped metal patch.

[0026] like Figure 1 、 2 As shown in Figure 3, the top and bottom metal structures of the reconfigurable transflective metasurface are rotationally symmetric. The bottom metal structure is obtained by rotating the top metal structure 90° along the normal direction. Therefore, it is polarization-insensitive to incident electromagnetic waves.

[0027] like Figure 4 、 Figure 5As shown, the metasurface units are electrically connected via edge square ring metal patches, creating a series power feed mechanism. This results in a simple and clear power feed mechanism. To ensure damage detection during actual processing and testing of the diodes, and to facilitate subsequent regular inspection and repair, the soldering direction of each column of diodes on the top metal structure of the reconfigurable transflective surface array remains consistent. Similarly, due to its rotational nature, the soldering direction of each row of diodes on the bottom metal structure remains consistent.

[0028] Furthermore, because its dielectric substrate is a single-layer, ultra-thin dielectric substrate with flexible and bendable properties, it can conform to carrier platforms of varying curvatures. The dielectric substrate material is Rogers 4350b, which is suitable for metasurface dielectric substrates because of its low dielectric constant and low dielectric loss, ensuring signal integrity and efficiency in high-frequency applications. Its high thermal stability (glass transition temperature exceeding 280°C) and excellent mechanical strength and dimensional stability ensure stable performance in various operating environments. In addition, Rogers 4350B's chemical stability enables it to operate reliably for long periods of time in complex environments. These properties together make it an ideal choice for high-performance metasurface designs.

[0029] The present invention achieves strong electromagnetic shielding effects and compatibility with normal communication signal reception and transmission in different frequency bands by controlling the voltage switching state. That is, by controlling the voltage loading size, the free space equivalent impedance of the PIN diode is changed, thereby changing the electromagnetic response of the metasurface unit to the incident electromagnetic wave, thereby realizing the reconfigurable function of the curved conformal ultra-thin transflective integrated skin.

[0030] A PIN diode is loaded into the gap between the rectangular metal patches on both sides and the central cross-shaped metal patch. When the voltage across the PIN diode is greater than its conduction voltage, the metasurface structure changes from a high-resistance state to a low-resistance state, and the corresponding passband and stopband positions also change. When a large bias voltage is applied, the diode is in the on state. At this time, the surface impedance of the curved, conformal, ultra-thin, transflective, and integrated skin changes from a high-resistance state to a low-resistance state, achieving the regulation of the passband and stopband, with low frequencies as the stopband and high frequencies as the passband. When a small bias voltage is applied or no power is applied, the diode is in the off state. At this time, the surface impedance of the curved, conformal, ultra-thin, transflective, and integrated skin changes from a low-resistance state to a high-resistance state, achieving the regulation of the passband and stopband, with high frequencies as the stopband and low frequencies as the passband.

[0031] When the diode is in the cut-off state, the low frequency is in the wave-transmitting state and the high frequency is in the wave-reflecting state; when the diode is in the on state, the low frequency is in the wave-reflecting state and the high frequency is in the wave-transmitting state, among which the wave-transmitting state is the communication state and the reflection state is the shielding state.

[0032] like Figure 6As shown, the simulated S of the curved surface conformal ultra-thin transflective integrated skin in the wave-transmitting state and the shielding state 21 Parameter diagram. When the PIN diode is in the off state, the reconfigurable transflective metasurface exhibits a high-impedance state. At low frequencies between 2.7 and 3.8 GHz, the structure exhibits an insertion loss of less than 1 dB, allowing electromagnetic waves to pass through the metasurface with virtually no loss. Frequency bands outside the passband are considered stopbands, reflecting nearly all incident electromagnetic waves. Correspondingly, when the PIN diode is in the on state, the passband shifts to 7.6-9.1 GHz.

[0033] like Figure 7 As shown, the simulated S of the curved surface conformal ultra-thin transflective integrated skin in the wave-transmitting state and the shielding state 11 Parameter diagram. In the corresponding passbands of the PIN diode's on and off states, the reconfigurable transflective metasurface has a low reflection coefficient, while in the corresponding stopband, the reflection coefficient is high, strongly reflecting the incident electromagnetic wave.

[0034] In summary, the present invention proposes a curved, conformal, ultra-thin, transflective, integrated skin. By altering the on and off states of the PIN diodes on the metasurface, the design switches between a transparent and reflective band. When an electromagnetic wave is incident, the wave passes through the metasurface almost losslessly in the transparent state, while being almost completely reflected in the reflective state. This design not only enables dynamic control of the electromagnetic wave propagation path but also significantly simplifies system complexity and cost. Due to its single-layer dielectric loading and ultra-thin profile, the design is flexible and bendable, meeting the curvature requirements of most stealth platforms.

[0035] Furthermore, the present invention's curved, conformal, ultra-thin, transflective integrated skin utilizes a simple electronic control method to rapidly switch between wave-transmitting and reflective states, providing an efficient and flexible electromagnetic wave management solution. It is particularly suitable for applications in smart antennas, communications systems, and radar technology, meeting the high-performance and high-reliability requirements of modern electronic systems.

[0036] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0037] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A curved conformal ultra-thin transflective integrated skin, characterized in that: The metasurface comprises a plurality of periodically arranged metasurface units, each of which is printed on a dielectric substrate using a double-layer metal structure, including: a top metal structure, a bottom metal structure, and a dielectric substrate, wherein: The top metal structure is placed on the bottom of the dielectric substrate and includes a central cross-shaped metal patch, an edge square ring metal patch, and rectangular metal patches on both sides. The central cross-shaped metal patch is placed at the center of the dielectric substrate, the edge of the edge square ring metal patch coincides with the edge of the dielectric substrate, the rectangular metal patches on both sides are placed between the central cross-shaped metal patch and the edge square ring metal patch, connected to the edge square ring metal patches, leaving a gap with the central cross metal patch, and PIN diodes are loaded in the gap between the rectangular metal patches on both sides and the central cross-shaped metal patch; the bottom metal structure is placed on the bottom surface of the dielectric substrate and is obtained by rotating the top metal structure 90 degrees according to the normal direction. The top cross-shaped metal patch and the bottom cross-shaped metal patch are connected through metal through holes.

2. The curved surface conformal ultra-thin transflective integrated skin according to claim 1, characterized in that: The dielectric substrate is made of Rogers 4350b.

3. The curved surface conformal ultra-thin transflective integrated skin according to claim 1, characterized in that: When soldering diodes on the top metal structure, the soldering direction of each column of diodes remains consistent; when soldering diodes on the bottom metal structure, the soldering direction of each row of diodes remains consistent.

4. The curved surface conformal ultra-thin transflective integrated skin according to claim 1, characterized in that: The metasurface units are electrically connected through edge square ring metal patches, forming a series feeding method.

5. The curved surface conformal ultra-thin transflective integrated skin according to claim 1, characterized in that: By controlling the voltage switching state, strong electromagnetic shielding effect in different frequency bands is achieved, which is compatible with normal communication signal transmission and reception. Specifically: By controlling the voltage loading, the free-space equivalent impedance of the PIN diode is changed, thereby changing the electromagnetic response of the metasurface unit to the incident electromagnetic wave, thus achieving the reconfigurable function of the curved, conformal, ultra-thin, transflective integrated skin. When a larger bias voltage is applied, the diode is in the on-state, and the surface impedance of the curved conformal ultra-thin transflective integrated skin changes from a high-resistance state to a low-resistance state, thereby realizing the regulation of the passband and stopband, wherein the low frequency is the stopband and the high frequency is the passband; when a smaller bias voltage is applied or no power is applied, the diode is in the off-state, and the surface impedance of the curved conformal ultra-thin transflective integrated skin changes from a low-resistance state to a high-resistance state, thereby realizing the regulation of the passband and stopband, wherein the high frequency is the stopband and the low frequency is the passband.

6. The curved surface conformal ultra-thin transflective integrated skin according to claim 1, characterized in that: When the diode is in the cut-off state, the low frequency is in the wave-transmitting state and the high frequency is in the wave-reflecting state; when the diode is in the on state, the low frequency is in the wave-reflecting state and the high frequency is in the wave-transmitting state, among which the wave-transmitting state is the communication state and the reflection state is the shielding state.

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