Cover-based ultra-wideband 1-bit reconfigurable metasurface with switchable frequency bands

Abstract

The invention discloses a cladding-based ultra wide band 1-bit reconfigurable metasurface with switchable frequency bands, which comprises a basic unit, and is characterized in that the basic unit comprises a dielectric substrate, a metal patch and a PIN (Personal Identification Number) diode; the metal patch is positioned on the upper surface of the dielectric substrate; the metal patches are two axisymmetric metal patches, an interval is formed between the two axisymmetric metal patches, the PIN diode is arranged at the interval, and the two axisymmetric metal patches are connected through the PIN diode located in the center of the unit; a coating is loaded on the surface of the basic unit and is used for enhancing or expanding the regulation and control capability of the basic unit; an air layer is arranged between the surface of the basic unit and the coating. By loading a specific coating on the surface of the basic unit, frequency band switching and 94% relative bandwidth can be realized. According to the invention, the regulation and control capability of the reconfigurable metasurface on electromagnetic waves is greatly improved, and the breakthrough progress of an intelligent metasurface platform is realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of reconfigurable metasurfaces, and particularly relates to a cladding-based switchable-band ultra-wideband 1-bit reconfigurable metasurface. Background Art

[0002] The working bandwidth of traditional reconfigurable metasurfaces is generally small. Once fabricated into physical objects, they can only rely on mechanisms such as mechanical, electro-optic, and phase change materials to achieve dynamic regulation of phase, frequency, polarization, bandwidth, and beam. If one wants to design a frequency-switching 1-bit reconfigurable metasurface that can continuously cover the C / X / Ku bands, difficulties such as complex structure, increased power consumption, high system design requirements, and high cost will be faced.

[0003] Reconfigurable metasurfaces can precisely manipulate the propagation direction, frequency response, and energy distribution of electromagnetic waves, and have gradually evolved into the core elements of advanced electromagnetic systems. This material has broad application prospects in fields such as radar detection, electromagnetic compatibility design, aerospace communication, and wireless sensor networks. However, for existing reconfigurable metasurfaces, the following defects still generally exist:

[0004] Traditional reconfigurable metasurface designs are often optimized for fixed frequency bands and are less adaptable to frequency changes or multiple frequency band interferences. Moreover, once a reconfigurable metasurface is fabricated into a physical object, the means for subsequent dynamic regulation are extremely limited, mainly relying on a few mechanisms such as mechanical, electro-optic, and phase change materials. By means of these mechanisms, dynamic adjustment of characteristics such as phase, frequency, polarization, bandwidth, and beam can be achieved to a certain extent. However, the limitations of the methods greatly restrict the wide application and performance improvement of reconfigurable metasurfaces.

[0005] In the research and development process of the current metasurface technology field, although traditional 1-bit reconfigurable metasurfaces have shown certain advantages and application potential in many aspects, however, they have significant limitations in terms of the ability to increase bandwidth. Traditional 1-bit reconfigurable metasurfaces mainly achieve their functions based on specific design architectures and working mechanisms. This design method exposes its inherent deficiencies when facing the increasing demand for bandwidth increase. Its internal physical structure and working mode are relatively fixed and difficult to flexibly adapt to different frequency bands and wider range of signal processing requirements.

[0006] The traditional ultra-wideband 1-bit reconfigurable metasurface has a complex structure and increased costs. The complex structure not only greatly increases the design difficulty but also poses extremely high requirements for process precision. Even the slightest deviation may affect the performance. Moreover, the low structural versatility makes it difficult to adapt to other designs, severely limiting its popularization and application. At the same time, in order to simplify the design and achieve functions, existing metasurfaces often use two or more PIN diodes, varactor diodes, etc. On the one hand, this greatly increases the cost and loss. On the other hand, it reduces the robustness of the system.

[0007] The surface-mounted PIN diode of the existing electronically controlled metasurface is a key component, but it often has no protection structure and is extremely vulnerable to environmental influences and human damage.

[0008] In N.Thi Toan,T.T.Thuy Quynh,T.V.Bang Giang and N.M.Tran,"AI-bitUltra-Wideband Reconfigurable Intelligent Surface with Multilayer Structurefor Beyond5G,"2024International Conference on Advanced Technologies forCommunications(ATC),Ho Chi Minh City,Vietnam,2024,pp.980-985., a 1-bit reconfigurable intelligent surface unit with a multilayer structure was proposed, which can maintain a phase difference of 180° (±30°) between 9.38 GHz and 12.68 GHz, approximately a 30% relative bandwidth. However, this unit structure adopts a multilayer design and integrates components such as PIN diodes and RF chokes, which increases the manufacturing cost and process complexity to a certain extent. From the perspective of mass production and practical application, the high cost may limit its popularization, and the complex manufacturing process may also affect the consistency and stability of the product.

[0009] In H. Shi et al., "An Ultrawideband 1-Bit Suspended Reconfigurable Intelligent Surface for Enhancing Wireless Coverage," in IEEE Antennas and Wireless Propagation Letters, vol. 23, no. 12, pp. 4613-4617, Dec. 2024, an ultrawideband 1-bit suspended reconfigurable intelligent surface is designed. The RIS unit consists of two metal gratings connected by PIN diodes, a dielectric-air-dielectric sandwich, and a metal reflection layer. In the ultrawideband range of 2.75 GHz - 6 GHz, a stable reflection phase difference of 180° ± 30° can be achieved between the on-state and off-state of the PIN diode, and the relative bandwidth reaches 74.3%. However, there is still room for improvement in the frequency band coverage. Summary of the Invention

[0010] In order to overcome the deficiencies of the above-mentioned prior art, the purpose of the present invention is to provide a cladding-based switchable-band ultrawideband 1-bit reconfigurable metasurface, which will greatly increase the electromagnetic wave regulation ability of the reconfigurable metasurface and achieve a breakthrough in the intelligent metasurface platform.

[0011] In order to achieve the above purpose, the technical solution adopted by the present invention is:

[0012] A cladding-based switchable-band ultrawideband 1-bit reconfigurable metasurface, including a basic unit, the basic unit includes a dielectric substrate, a metal patch, and a PIN diode;

[0013] The metal patch is located on the upper surface of the dielectric substrate;

[0014] The metal patch is composed of two axially symmetric metal patches with a gap between them. A PIN diode is arranged at the gap, and the two axially symmetric metal patches are connected by a PIN diode located at the center of the unit;

[0015] A cladding is loaded on the surface of the basic unit to enhance or expand the regulation ability of the basic unit;

[0016] There is an air layer between the surface of the basic unit and the cladding.

[0017] The dielectric substrate material is selected as Taconic TLY, with a thickness of 2 mm, a relative dielectric constant of 2.2, a loss tangent of 0.0009, and the size of a single patch is 3.35 mm * 8 mm.

[0018] The gap between the metal patches is 0.3 mm.

[0019] Taking the center of the lower surface of the dielectric layer as the coordinate origin, a spatial rectangular coordinate system is established, with the z-axis perpendicular to the upper surface of the dielectric layer, the y-axis horizontally to the right, and the x-axis longitudinally forward. The two patches are symmetric about the y-axis;

[0020] In HFSS, a model is established for full-wave simulation. The boundary condition is set as a periodic boundary to simulate an infinite periodic array. A Floquet port is set on the upper surface of the top air layer, and TM wave incidence is selected.

[0021] By adjusting the patch width, the resonant frequency can be adjusted. The basic unit can achieve 1-bit phase control from 11.5 GHz to 15.6 GHz, with a relative bandwidth of 30%.

[0022] A cladding layer 1 is loaded above the basic unit, and there is an air layer between the cladding layer 1 and the basic unit.

[0023] The cladding layer 1 includes a layer of dielectric substrate, and metal patches arranged in a 5*5 period are set on the upper surface of the dielectric substrate.

[0024] The material of the dielectric substrate is selected as Rogers RT / duroid 5880, with a thickness of 0.508 mm, a relative dielectric constant of 2.2, a loss tangent of 0.0009, the size of a single patch is 1.5 mm * 1.5 mm, and the distance between each patch is 0.1 mm;

[0025] The patch period is 1.6 mm, less than one-tenth of the wavelength, which is a sub-wavelength metasurface. Through the resonance response of the artificial micro-structure, it has the equivalent characteristics of a metamaterial.

[0026] The cladding layer 1 is composed of a 1.6 mm * 1.6 mm * 0.508 mm dielectric layer symmetric about the middle axis and 5*5 arrays of 1.5 mm * 1.5 mm upper surface metal patches, introducing additional resonant frequencies. By adjusting the thickness of the air layer and the patch width of the cladding layer 1, the resonant frequency is adjusted and the bandwidth is increased; the basic unit can achieve 1-bit phase control from 7 GHz to 11.5 GHz, with a relative bandwidth of 49%.

[0027] A cladding layer 2 is loaded directly above the basic unit, and there is an air layer between the cladding layer 2 and the basic unit.

[0028] The cladding layer 2 is composed of two layers of dielectric substrates and two layers of metal patches arranged in a 5*5 period.

[0029] The two layers of dielectric substrates are connected up and down. The thickness of the upper dielectric plate is 0.508 mm, the size of a single patch is 0.5 mm * 0.5 mm, and the distance between each patch is 1.1 mm;

[0030] The thickness of the lower dielectric plate is 0.254 mm, the size of a single patch is 1.5 mm * 1.5 mm, and the distance between each patch is 0.1 mm.

[0031] The second cladding is divided into two layers. The upper layer is formed by arranging 5×5 arrays of a 1.6 mm×1.6 mm×0.508 mm dielectric layer with central symmetry and a 0.5 mm×0.5 mm upper surface metal patch; the lower layer is formed by arranging 5×5 arrays of a 1.6 mm×1.6 mm×0.254 mm dielectric layer with central symmetry and a 1.5 mm×1.5 mm upper surface metal patch.

[0032] The second cladding introduces additional resonant frequencies. By adjusting the air layer thickness and the patch widths of the two layers of the second cladding, the resonant frequencies are adjusted and the bandwidth is increased. The basic unit can achieve 1-bit phase control in the range of 5.5 GHz - 7 GHz, with a relative bandwidth of 24%.

[0033] The proposed cladding-based switchable-band ultra-wideband 1-bit reconfigurable metasurface, in the field of communication, its ultra-wideband characteristics are adapted to 5G / 6G multi-band communication systems, and can efficiently process signal transmission and optimize the utilization of spectrum resources; in the scenarios of radar detection and non-destructive testing, through precise phase control, it can significantly improve the target recognition accuracy and the material defect detection ability.

[0034] When the metasurface unit is applied to the surfaces of aircraft and ships, the phase of the incident electromagnetic wave can be controlled.

[0035] Advantages of the present invention:

[0036] The working frequency band of the present invention covers 5.6 GHz - 15.6 GHz. Through the unique method of loading the cladding, only a single PIN diode is required to achieve 1-bit phase control, which not only greatly simplifies the complex control structure, but also fundamentally reduces the system complexity and manufacturing cost, providing a new technical path for the design of metasurface units.

[0037] Specifically, by selecting different loaded claddings, the unit can flexibly achieve frequency band switching and 1-bit phase control within the ultra-wide frequency band of 5.6 GHz - 15.6 GHz. This design has multiple advantages: the structure is simple and clear, significantly reducing the design and processing difficulty; the cost is low, adapting to the needs of large-scale production; it has strong robustness and can operate stably in complex electromagnetic environments, effectively overcoming the pain points of the complex structure and demanding process requirements of traditional metasurface units.

[0038] At the practical application level, this metasurface unit demonstrates broad applicability and technical advantages. In the field of communication, its ultra-wideband characteristics are suitable for 5G / 6G multi-band communication systems, which can efficiently process signal transmission, optimize the utilization of spectrum resources, and provide support for high-rate and low-latency communication. In the scenarios of radar detection and non-destructive testing, through precise phase regulation, it can significantly improve the target recognition accuracy and the ability to detect material defects. When the metasurface unit is applied to the surfaces of aircraft and ships, by regulating the phase of the incident electromagnetic wave, the reflected wave can be made to interfere destructively in a specific direction, effectively reducing the radar cross section (RCS) of the equipment and greatly enhancing the stealth performance and survivability in complex environments. This design that combines high efficiency, low cost, and high reliability lays a solid foundation for the engineering application of metasurface technology in multiple fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 is the structural diagram of the basic unit.

[0040] Figure 2 is the structural diagram of the unit with the first cladding loaded.

[0041] Figure 3 is the structural diagram of the unit with the second cladding loaded.

[0042] Figure 4 is the schematic diagram of the phase difference between two states of the basic unit.

[0043] Figure 5 is the schematic diagram of the phase difference between two states of the unit with the first cladding loaded.

[0044] Figure 6 is the schematic diagram of the phase difference between two states of the unit with the second cladding loaded. DETAILED DESCRIPTION OF THE INVENTION

[0045] The present invention will be further described in detail below with reference to the accompanying drawings.

[0046] The present invention discloses a cladding-based switchable-band ultra-wideband 1-bit reconfigurable metasurface;

[0047] The schematic diagram of the basic unit structure is as Figure 1 shown. The unit size is 8mm * 8mm, including a layer of dielectric substrate, two metal patches, and a PIN diode;

[0048] The dielectric substrate material is selected as Taconic TLY, with a thickness of 2mm, a relative dielectric constant of 2.2, and a loss tangent of 0.0009. The patches are located on the upper surface of the dielectric layer. The size of a single patch is 3.35mm * 8mm, and two axially symmetric metal patches are separated by 0.3mm and connected by a PIN diode located at the center of the unit.

[0049] Taking the center of the lower surface of the dielectric layer as the coordinate origin, a spatial rectangular coordinate system is established, with the z-axis perpendicular to the upper surface of the dielectric layer, the y-axis horizontally to the right, and the x-axis longitudinally forward. The two patches are symmetric about the y-axis;

[0050] A model is established in HFSS for full-wave simulation. The boundary condition is set as a periodic boundary to simulate an infinite periodic array for simulation. A Floquet port is set on the upper surface of the top air layer, and the TM wave incidence is selected. Figures 4 - 6 The vertical axis Y1 represents dB(S(1,1)).

[0051] To achieve phase tunability, the PIN diode model is selected as MADP-000907. Here, the LumpRLC boundary condition is used to represent the PIN diode, and the RLC series equivalent circuit parameters of the two states of the PIN diode switch are used to simulate the on and off of the actual diode. The on and off of the PIN diode affect the electrical structure of the microstrip patch on the unit surface at the operating frequency. A switch state table is used to represent the on and off states of the PIN diode, as shown in 0. By adjusting the patch width, the resonant frequency is adjusted. The final simulation results are as Figure 1 shown. This basic unit can achieve 1-bit phase regulation from 11.5 GHz to 15.6 GHz, with a relative bandwidth of 30%.

[0052] Table 1 Switch states

[0053] Switch state PIN state pinr pinl pinc ON Conduction 2.8 Ω 30 pH \ OFF Cut-off 0 Ω 30 pH 0.025 pF

[0054] The schematic diagram of the unit structure loaded with cladding one is as Figure 2 shown. The thickness of the air layer is 1 mm. Cladding one is located directly above the basic unit and is composed of a layer of dielectric substrate and metal patches arranged in a 5*5 period;

[0055] The patch period is 1.6 mm, which is less than one-tenth of the wavelength, making it a sub-wavelength metasurface. Through the resonance response of the artificial microstructure and the equivalent metamaterial characteristics, the structural size can be effectively reduced, and flexible and customizable electromagnetic regulation capabilities can be achieved.

[0056] The dielectric substrate material is selected as Rogers RT / duroid 5880, with a thickness of 0.508 mm, a relative dielectric constant of 2.2, a loss tangent of 0.0009, the size of a single patch is 1.5 mm * 1.5 mm, and the distance between each patch is 0.1 mm.

[0057] Cladding one is formed by arranging a 1.6 mm * 1.6 mm * 0.508 mm dielectric layer symmetric about the middle axis and 1.5 mm * 1.5 mm upper surface metal patches in a 5*5 array, which can introduce additional resonant frequencies. By adjusting the thickness of the air layer and the patch width of cladding one, the resonant frequency is adjusted and the bandwidth is increased. The final simulation results are asFigure 5 As shown, the basic unit loaded with Cladding 1 can achieve 1-bit phase control in the range of 7 GHz - 11.5 GHz, with a relative bandwidth of 49%.

[0058] The schematic diagram of the unit structure loaded with Cladding 2 is as shown in Figure 3 As shown, the thickness of the air layer is 0.3 mm. The loaded Cladding 2 is located directly above the basic unit and is composed of two dielectric substrates and two layers of metal patches arranged in a 5*5 periodic pattern. The dielectric substrate material is Rogers RO4003, with a relative dielectric constant of 3.55 and a loss tangent of 0.0027.

[0059] The two dielectric substrates are connected up and down. The thickness of the upper dielectric board is 0.508 mm, the size of a single patch is 0.5 mm * 0.5 mm, and the distance between each patch is 1.1 mm; the thickness of the lower dielectric board is 0.254 mm, the size of a single patch is 1.5 mm * 1.5 mm, and the distance between each patch is 0.1 mm.

[0060] Cladding 2 is divided into two layers. The upper layer is formed by arraying a 1.6 mm * 1.6 mm * 0.508 mm dielectric layer with a central symmetry and 0.5 mm * 0.5 mm upper surface metal patches in 5*5 groups; the lower layer is formed by arraying a 1.6 mm * 1.6 mm * 0.254 mm dielectric layer with a central symmetry and 1.5 mm * 1.5 mm upper surface metal patches in 5*5 groups.

[0061] The cladding can introduce additional resonant frequencies. By adjusting the thickness of the air layer and the patch widths of the two layers of Cladding 2, the resonant frequency is adjusted and the bandwidth is increased. The final simulation results are as shown in Figure 6 As shown, the basic unit loaded with Cladding 2 can achieve 1-bit phase control in the range of 5.5 GHz - 7 GHz, with a relative bandwidth of 24%.

[0062] For the basic unit structure, when the PIN diode is in the conducting state, the two metal patches are connected by the PIN diode, forming a specific current path. At this time, the current distribution is more concentrated, and the unit will generate a specific reflection phase or amplitude response to the incident electromagnetic wave; when the PIN diode is in the cut-off state, the two metal patches are disconnected, and the equivalent electromagnetic characteristics change. At this time, the current path is blocked, and the equivalent capacitance effect of the unit is enhanced, generating another reflection phase or amplitude response to the incident electromagnetic wave. Compared with the conducting state, the resonant frequency shifts and the scattering phase changes, resulting in a phase difference of 180° ± 20° between the two states, thus achieving 1-bit phase control, that is, using the impedance characteristics of the PIN diode to change the resonant response of the electromagnetic unit, thereby adjusting the phase of the reflected wave.

[0063] Introducing a cladding can adjust the equivalent impedance of the metasurface unit to match that of free space (377 Ω), reducing signal reflection caused by impedance mutation. The cladding is usually composed of a dielectric material with a relatively high dielectric constant. When the cladding is placed on the surface of the metamaterial, it enhances the electric field coupling between the structural units of the metamaterial, thereby increasing the equivalent capacitance C of the structure.

[0064] According to the resonance frequency formula When the equivalent inductance L remains unchanged (or the change is negligible), an increase in the equivalent capacitance C will, according to the frequency formula, lead to a decrease in the resonance frequency f. At the same time, the cladding will change the overall equivalent dielectric constant, causing the distribution of the electromagnetic field in the unit to change, altering the original electromagnetic resonance characteristics and achieving the adjustment of the resonance frequency.

[0065] Embedding periodic metal patterns in the cladding can be regarded as an artificial electromagnetic structure, which will change the equivalent dielectric constant and permeability of the cladding region. When the metal patterns interact with electromagnetic waves, a resonance effect will occur. When electromagnetic waves are incident, the periodic metal patterns will change the current distribution of the unit. The current flowing on the metal patterns generates an additional magnetic field, which couples with the original electromagnetic field of the basic unit to adjust the overall field distribution. The periodic metal patterns selectively transmit or reflect specific frequency bands to optimize the working bandwidth. At the same time, the cladding structure introduces additional resonance modes to expand the bandwidth.

[0066] The present invention proposes a design scheme for a 1-bit reconfigurable metasurface unit based on a cladding. The core of this scheme lies in the ability to select loaded claddings with different dielectric constants according to actual needs, flexibly and accurately adjust the resonance frequency density, and effectively realize the regulation of surface wave coupling, opening up a new idea for optimizing the performance of the metasurface.

[0067] The present invention proposes a frequency-band adjustable 1-bit reconfigurable metasurface design with a switched cladding. This design pioneerly introduces a loaded cladding into the field of metasurface design. Through this unique method, it successfully realizes 1-bit phase regulation with frequency-band selection function, opening up an economical and efficient low-cost solution path for programmable metasurface designs that meet different application requirements.

[0068] The present invention proposes a frequency-switching ultra-wideband 1-bit reconfigurable metasurface that can continuously cover the C / X / Ku bands. The characteristic of continuous coverage of the C / X / Ku bands greatly expands its application scenarios. Moreover, the relative bandwidth of this metasurface reaches 94%, far exceeding similar products, bringing new possibilities for the development of related fields. The present invention proposes a method for protecting the adjustable device on the surface of the metasurface. Through cladding loading, it effectively isolates the reconfigurable device on the metasurface from the environment, greatly improving the reliability of the metasurface.

Claims

1. A cladding-based switchable frequency band ultra-wideband 1-bit reconfigurable metasurface, characterized in that: It comprises a basic unit, wherein the basic unit comprises a dielectric substrate, a metal patch and a PIN diode; The metal patch is located on the upper surface of the dielectric substrate; The metal patches are two axisymmetric metal patches, with a gap between them, a PIN diode is arranged at the gap, and the two axisymmetric metal patches are connected by the PIN diode located at the center of the unit; The surface of the basic unit is loaded with a coating to enhance or expand the control capability of the basic unit; There is an air layer between the surface of the base unit and the covering layer.

2. The cladding-based switchable frequency band ultra-wideband 1-bit reconfigurable metasurface according to claim 1, characterized in that: The dielectric substrate material is Taconic TLY, with a thickness of 2 mm, a relative dielectric constant of 2.2, a loss tangent of 0.0009, and a single patch size of 3.35 mm*8 mm; The metal patches are spaced 0.3 mm apart.

3. The cladding-based switchable frequency band ultra-wideband 1-bit reconfigurable metasurface according to claim 1, characterized in that: Take the center of the lower surface of the dielectric layer as the coordinate origin, establish a spatial rectangular coordinate system, with the z-axis perpendicular to the upper surface of the dielectric layer, the y-axis horizontally to the right, and the x-axis vertically forward, and the two patches are symmetrical about the y-axis; A model was established in HFSS for full-wave simulation. The boundary conditions were set to periodic boundaries to simulate infinite periodic arrays. A Floquet port was set on the upper surface of the top air layer, and TM wave incidence was selected.

4. The cladding-based switchable frequency band ultra-wideband 1-bit reconfigurable metasurface according to claim 1, characterized in that: The resonant frequency is adjusted by adjusting the patch width, and the basic unit achieves 1-bit phase control from 11.5 GHz to 15.6 GHz, with a relative bandwidth of 30%.

5. The cladding-based switchable frequency band ultra-wideband 1-bit reconfigurable metasurface according to claim 1, characterized in that: A coating layer 1 is loaded on the base unit, and an air layer is between the coating layer 1 and the base unit; the coating layer 1 includes a dielectric substrate, and a metal patch arranged in a 5*5 periodic pattern is arranged on the dielectric substrate; The dielectric substrate material is Rogers RT / duroid 5880, with a thickness of 0.508mm, a relative dielectric constant of 2.2, a loss tangent of 0.0009, a single patch size of 1.5mm*1.5mm, and a spacing of 0.1mm between each patch; The patch period is 1.6mm, which is less than one tenth of the wavelength. It is a sub-wavelength metasurface, which has equivalent special medium properties through the resonant response of the artificial microstructure.

6. The cladding-based switchable frequency band ultra-wideband 1-bit reconfigurable metasurface according to claim 5, characterized in that: The first cladding layer is composed of a 5*5 array of a 1.6mm*1.6mm*0.508mm dielectric layer and a 1.5mm*1.5mm upper surface metal patch with a central axis symmetry, introducing an additional resonant frequency. By adjusting the thickness of the air layer and the width of the patch of the first cladding layer, the resonant frequency is adjusted and the bandwidth is increased. The basic unit can achieve 1-bit phase control from 7 GHz to 11.5 GHz, with a relative bandwidth of 49%.

7. The cladding-based switchable frequency band ultra-wideband 1-bit reconfigurable metasurface according to claim 1, characterized in that: The second covering layer is loaded directly above the basic unit, and an air layer is between the second covering layer and the basic unit; The second cladding layer is composed of two layers of dielectric substrates and two layers of metal patches arranged in a 5*5 periodic pattern; The two layers of dielectric substrates are connected up and down, the thickness of the upper dielectric plate is 0.508mm, the size of a single patch is 0.5mm*0.5mm, and each patch is 1.1mm apart; The thickness of the lower dielectric board is 0.254mm, the size of a single patch is 1.5mm*1.5mm, and each patch is 0.1mm apart.

8. The cladding-based switchable frequency band ultra-wideband 1-bit reconfigurable metasurface according to claim 7, characterized in that: The covering layer is divided into two layers. The upper layer is composed of a 5*5 array of a 1.6mm*1.6mm*0.508mm dielectric layer with a central axis symmetry and a 0.5mm*0.5mm upper surface metal patch; the lower layer is composed of a 5*5 array of a 1.6mm*1.6mm*0.254mm dielectric layer with a central axis symmetry and a 1.5mm*1.5mm upper surface metal patch.

9. The cladding-based switchable frequency band ultra-wideband 1-bit reconfigurable metasurface according to claim 8, characterized in that: The second cladding layer introduces an additional resonant frequency. By adjusting the thickness of the air layer and the patch width of the second cladding layer, the resonant frequency is adjusted and the bandwidth is increased. The basic unit can achieve 1-bit phase control of 5.5GHz-7GHz, with a relative bandwidth of 24%.

10. The application of a cladding-based switchable frequency band ultra-wideband 1-bit reconfigurable metasurface according to any one of claims 1 to 9, characterized in that: In the field of communications, the ultra-wideband 1-bit reconfigurable metasurface with switchable frequency bands based on the coating is suitable for 5G / 6G multi-band communication systems due to its ultra-wideband characteristics, and can efficiently process signal transmission and optimize the utilization of spectrum resources; In radar detection and non-destructive testing scenarios, precise phase control can significantly improve target recognition accuracy and material defect detection capabilities; When the metasurface unit is applied to the surface of aircraft or ships, the phase of the incident electromagnetic wave can be adjusted.

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