A temperature-voltage-controlled reconfigurable reflective polarization converter

Abstract

The present invention relates to a reconfigurable reflective polarization converter, and more particularly, to a temperature-voltage-controlled reconfigurable reflective polarization converter. The converter comprises a bottom metal reflector, an intermediate dielectric layer, and a top resonant unit layer, arranged sequentially from bottom to top. The top resonant unit layer comprises a plurality of square metal sheets, which are periodically arranged in an M×N pattern on the intermediate dielectric layer to form a periodic array. A phase-change material is coated between adjacent square metal sheets; the phase-change material is VO2 nanopowder dispersed in a PVP matrix. The present invention enables temperature and voltage control of the converter's operating state, is insensitive to the polarization and angle of incidence of the incident electromagnetic wave, exhibits strong adjustability and frequency flexibility, and has the potential to be easily expanded to the terahertz and even optical bands. The converter also features a simple manufacturing process and has significant application value in fields such as antenna radiation and radar cross-section reduction for dynamic electromagnetic wave control.

Description

Technical Field

[0001] The present invention relates to a reconfigurable reflective polarization converter, in particular to a temperature and voltage controlled reconfigurable reflective polarization converter. Background Art

[0002] With the rapid development of electronic countermeasures and communications technologies, the demand for electromagnetic wave manipulation is growing stronger. Polarization, a key vector characteristic of electromagnetic waves, has wide applications in optical wave fields, microwave communications, and radar anti-interference. Therefore, the technology for manipulating the polarization of electromagnetic waves has become a key topic in electromagnetic research. The polarization of a plane wave refers to the direction of oscillation of the electric field in the plane of electromagnetic wave propagation.

[0003] Polarization metamaterials (MMs), also known as artificial materials, possess many unique properties not found in nature, enabling flexible manipulation of electromagnetic waves. They are a new type of artificial composite material with at least one of a negative dielectric constant or permeability, and are generally composed of a periodic structure. These unique properties have led to the fabrication of numerous specialized devices and materials, such as perfect absorbers, filtering surfaces, and polarization conversion metasurfaces (PCMs). Polarization metamaterials are primarily used to manipulate the polarization of electromagnetic waves, and are categorized into transmission and reflection types. Transmission-type metamaterials are generally considered to suffer from high losses and a narrow bandwidth, while reflection-type metamaterials offer significant improvements in these two areas. However, their narrow operating bandwidth remains a major limitation in their engineering applications. One research direction is to use multi-point resonance to broaden its operating frequency band. Xi Gao et al. designed an ultra-wideband high-efficiency linear polarization converter using a double V-shaped metal surface, and Xu Jin et al. designed an ultra-wideband linear polarization converter using a square open ring. Vanadium dioxide is a typical strong electron-correlated metal oxide. When subjected to external stimuli such as heat, voltage or light, it can undergo a reversible transformation from a low-temperature insulating state (M phase) to a high-temperature semiconductor state (R phase). The lattice structure changes from a monoclinic rutile structure to a tetragonal rutile structure, and the resistivity will have a mutation of 3-5 orders of magnitude. It has huge application potential in the fields of new storage devices, intelligent electromagnetic protection materials, and terahertz technology.

[0004] Since traditional polarization methods such as gratings and dichroic crystals are used, they have disadvantages such as complex structure, large size and narrow working bandwidth, which limits their application in practical engineering. Summary of the Invention

[0005] The purpose of the present invention is to provide a temperature-voltage-controlled reconfigurable reflective polarization converter, which realizes the control of the converter's operating state by temperature and voltage. It has the characteristics of being insensitive to the polarization and incident angle of the incident electromagnetic wave, strong adjustability, frequency flexibility, and the potential to be easily expanded to the terahertz and even optical bands. The manufacturing process is simple and has great application value in the fields of dynamic electromagnetic wave control such as antenna radiation and radar scattering cross-section reduction.

[0006] The present invention provides a temperature-voltage-controlled reconfigurable reflective polarization converter, comprising a bottom metal reflector, an intermediate dielectric layer, and a top resonant unit layer, which are arranged in sequence from bottom to top. The top resonant unit layer comprises a plurality of square metal sheets, which are periodically arranged in an M×N form on the intermediate dielectric layer to form a periodic array. Phase change material is coated between adjacent square metal sheets; the phase change material is obtained by dispersing VO2 nanopowder in a PVP matrix.

[0007] The present invention realizes the reconfigurability of the super surface by coating a phase change material between the adjacent square metal sheets of the top resonance unit layer, wherein the phase change material is obtained by dispersing VO2 nanopowder in a PVP aqueous solution matrix.

[0008] Preferably, the square-shaped metal sheet is tilted at 45°, that is, the edges of the square-shaped metal sheet are tilted at 45° relative to the intermediate dielectric layer and the bottom metal reflective plate. The four edges of the square-shaped metal sheet extend outward to form an extension sheet. A contact sheet is provided at one end of the extension sheet. The edge of the contact sheet is at 45° to the edge of the extension sheet. There is a gap between adjacent contact sheets, and phase change material is coated in two opposite gaps on each of the square-shaped metal sheets.

[0009] Preferably, the preparation method of the phase change material is: first preparing a PVP aqueous solution, and then dispersing VO2 nanopowder in the PVP aqueous solution to obtain the phase change material.

[0010] Preferably, the phase change material is prepared by first preparing a 3%-10% PVP aqueous solution, then dispersing VO2 nanopowder in the PVP aqueous solution, with the volume fraction of VO2 in the phase change material being 40%-80%. Using this phase change material, the film composition is simple, and the aqueous organic material PVP is safer and more environmentally friendly. To ensure the stability of the electrical properties of the prepared VO2 phase change material, and taking into account the mechanical properties of the composite film and its adhesion to the substrate, a 60% volume fraction of VO2 and a 40% volume fraction of PVP are used when preparing the reconfigurable polarization converter.

[0011] Preferably, the square metal sheet and the metal reflector are both made of copper-clad metal, and the electrical conductivity of the copper-clad metal used is , when the frequency is greater than 1 GHz, the skin depth of the metal copper is less than 2.06 μm, and the thickness of the metal copper is 35 μm.

[0012] Preferably, the square metal sheets are periodically arranged on the intermediate dielectric layer in the form of M×N to form a periodic array, wherein M≥12, N≥11, M and N are integers, and the period p=13-16 mm.

[0013] Preferably, the square side length of the square metal sheet is , the thickness of the gap is , the length of the gap is the same as the length of the contact piece, the length of the contact piece , the contact piece width , the extension piece width w 2=0.5-2mm.

[0014] Preferably, the thickness of the intermediate dielectric layer is h 2=0.5-1 mm.

[0015] Preferably, the middle dielectric layer adopts a high-frequency PCB circuit board with a dielectric constant of 3-5 and a loss tangent of 0.001-0.0037.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] (1) The present invention provides a temperature-voltage-controlled reconfigurable reflective polarization converter, which realizes the control of the polarization state of electromagnetic waves and the control of the converter's operating state by temperature and voltage. Simulation and experimental results show that when VO2 is in a low-temperature insulating state, the structure achieves cross-reflection on the surface due to the resonance of the periodic metal structure. When the material is in a high-temperature metallic state, the metal structure is destroyed and the material can achieve co-polarization emission. At the same time, due to the symmetry of the unit structure, the converter is also insensitive to the polarization and incident angle of the incident electromagnetic wave.

[0018] (2) The present invention provides a temperature-voltage-controlled reconfigurable reflective polarization converter. An electrically controlled reconfigurable polarization converter is designed based on a 45° rotated square shape. Before the phase change, VO2 is in a high-impedance state. The cross-polarization rate of this structure is higher than 70% at 6.76-7.18 GHz, and the co-polarization rate is less than 10%. After the VO2 phase change, the cross-polarization rate of the polarization converter is almost 0. This indicates that VO2 achieves voltage control of the designed structure, with a modulation depth greater than 90%. This VO2-based reconfigurable polarization converter has many advantages, including strong adjustability, frequency flexibility, and the potential to be easily expanded to the terahertz and even optical bands. The manufacturing process is simple, and it has great application value in the fields of dynamic electromagnetic wave control, such as antenna radiation and radar cross-section reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 This is a side view of the structure of each unit of the reconfigurable reflective polarization converter;

[0021] Figure 2 It is a structural diagram of some structural units of the reconfigurable reflective polarization converter;

[0022] Figure 3 This is a structural diagram of a structural unit of a reconfigurable reflective polarization converter;

[0023] Figure 4 yes Figure 3 Enlarged view of the middle dashed box;

[0024] Figure 5 Phase change material, where (a) is the design diagram of the phase change material test electrode, (b) is the actual diagram of the phase change material test electrode, and (c) is the SEM image of the phase change material;

[0025] Figure 6 It is the temperature-induced phase change curve of the phase change material coating;

[0026] Figure 7 Temperature-induced phase transition curves of composite materials with different VO2 volume fractions (20%, 30%);

[0027] Figure 8 Temperature-induced phase transition curves of composite materials with different VO2 volume fractions (70%, 80%);

[0028] Figure 9 Temperature-induced phase transition curves of composite materials with different VO2 volume fractions (40%, 60%);

[0029] Figure 10 Change curve of resistance and VO2 volume fraction before and after phase change of phase change material composite film;

[0030] Figure 11 The left figure shows the temperature-induced phase change curve of the phase change material in the reconfigurable polarization converter, and the right figure shows the temperature-induced phase change test curve of the reconfigurable converter;

[0031] Figure 12 Single-row electroinduced phase change curve of phase change material with reconfigurable polarization converter;

[0032] Figure 13 Polarization rate curves of the reconfigurable polarization converter before (a) and after (b) phase change;

[0033] Figure 14 Polarization conversion rate curve (a) and modulation depth diagram (b) of the reconfigurable polarization converter before and after phase change;

[0034] Figure 15 Physical diagram of some unit structures;

[0035] Figure 16 (a) is the test polarization curve of the reconfigurable polarization converter before and after the phase change, and (b) is the simulation polarization curve of the reconfigurable polarization converter before and after the phase change.

[0036] Description of reference numerals:

[0037] 1- square metal sheet, 2- intermediate dielectric layer, 3- extension sheet, 4- contact sheet, 5- VO2 phase change material, 6- bottom metal reflector. DETAILED DESCRIPTION

[0038] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present application belongs.

[0039] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the embodiments described are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0040] Example

[0041] A temperature-voltage controlled reconfigurable reflective polarization converter, such as Figure 1 As shown, it includes a bottom metal reflector 6, an intermediate dielectric layer 2 and a top resonant unit layer arranged in sequence from bottom to top, as shown in FIG. Figure 2 As shown, the top resonant unit layer includes a plurality of square metal pieces 1, which are periodically arranged in the form of 12×11 on the middle dielectric layer to form a periodic array ( Figure 2 Only the 3×3 part is drawn, and the rest is omitted). The period p = 14.5 mm.

[0042] Figure 3 This is an enlarged view of one of the units. Figure 4 yes Figure 3The enlarged image of the dotted box is as follows: Figure 2-4 As shown, the square metal sheet 1 is tilted at 45 degrees, and the four sides of the square metal sheet 1 extend outward to form an extension sheet 3. A contact sheet 4 is set at one end of the extension sheet 3. The side of the contact sheet 4 is at 45 degrees to the side of the extension sheet 3. There is a gap between adjacent contact sheets 4. VO2 phase change material 5 is coated in two opposite gaps on each square metal sheet 1. That is, VO2 phase change material 5 is coated on two opposite corners of each square metal sheet 1, and the other two opposite corners are gaps and are not coated with VO2 phase change material. The square side length of the square metal sheet 1 is , the thickness of the gap , the gap length is the same as the length of contact piece 4, the length of contact piece 4 , contact piece 4 width , extension piece 3 width w 2=2mm.

[0043] The preparation method of the coated VO2 phase change material 5 (hereinafter referred to as phase change material) is as follows: first, a PVP aqueous solution with a mass fraction of 5% is prepared, and then a certain amount of VO2 nanopowder is dispersed in the PVP aqueous solution matrix, with the volume fraction of VO2 being 60% and the volume fraction of PVP being 40%.

[0044] The square metal sheet, extension sheet, contact sheet and metal reflector are all composed of metal clad copper. The square metal sheet, extension sheet and contact sheet are integrally formed. The metal clad copper used has high electrical conductivity. , when the frequency is greater than 1 GHz, the skin depth of the metal copper is less than 2.06 μm, and the thickness of the metal copper is 35 μm.

[0045] The middle dielectric layer uses high-frequency PCB circuit board Rogers4350B, with a dielectric constant of 3.48 and a loss tangent of 0.0037. The thickness of the middle dielectric layer is h 2=0.7 mm.

[0046] The phase change material prepared in the example was tested:

[0047] First, the resistance of the VO2 phase change material is tested.

[0048] The prepared VO2 phase change material is coated between two electrodes using a coating process. The design diagram of the phase change material test electrode is shown in the figure below. Figure 5 In (a), the electrode width is 2 mm, the spacing is 1 mm, and the actual image of the phase change material test electrode after the VO2 phase change material coating is dried is shown in the figure. Figure 5 As shown in (b) in . Figure 5 (c) is the SEM characterization of the VO2 phase change material coating after drying. It can be seen from the figure that the VO2 nanoparticles overlap each other. The temperature-dependent phase change curve of the VO2 phase change material coating is as follows Figure 6 shown.

[0049] Example 2

[0050] A temperature-voltage-controlled reconfigurable reflective polarization converter is provided, which is different from the embodiment only in that the volume fractions of VO2 and PVP in the VO2 phase change material are different.

[0051] By adjusting the ratio of VO2 nanoparticles, PVP and deionized water in the VO2 phase change material, VO2 phase change material composite films with VO2 volume fractions of 10%-90% were prepared, and the sum of the volume fractions of VO2 and PVP was 100%.

[0052] The temperature-induced phase transition curves of composite materials with different VO2 volume fractions are shown in Figure 7-9 As can be seen from the curves in the figure, the resistance of the prepared VO2 coating changes dramatically around 68°C during the heating and cooling process, indicating that the prepared VO2 coating can undergo temperature-induced phase transition under temperature changes. At a low temperature of 30°C, the resistance is 41KΩ, and at a high temperature of 90°C, the resistance is 320Ω, with a resistance change rate of more than 2 orders of magnitude.

[0053] When the volume fraction of VO2 is 10%, the VO2 junction resistance is infinite and cannot be measured by the device. When the volume fraction of VO2 is 20%, the resistance can only be measured when the temperature is higher than 70°C. Figure 7 As shown. When the resistance is higher than 40%, all samples can experience resistance mutation phenomenon, and the temperature of the phase transition is around 70℃. When the temperature is higher than 80℃, the resistance remains basically unchanged. Figure 9 The resistance variation curve of VO2 / PVP composite material is analyzed. The percolation threshold of VO2 / PVP composite material is 40%. When the volume fraction of VO2 in the composite material is higher than 40%, the electrical properties of the material change little.

[0054] The resistance and VO2 volume fraction curves of the phase change material composite film before and after phase change are shown in Figure 10 .

[0055] In order to ensure the stability of the electrical properties of the prepared VO2 composite material, and taking into account the mechanical properties of the composite film and the adhesion to the substrate, the volume fraction of VO2 was selected as 60% when preparing the reconfigurable polarization converter.

[0056] Example 1 is the best example. The polarization converter prepared in Example 1 was subjected to the following tests:

[0057] In order to study the effect of VO2 phase change material on the performance of polarization conversion metasurface, simulation test was carried out. In the simulation, VO2 was simplified to distributed resistance. ResBy adjusting the resistance value, the polarization converter performance of VO2 phase change material before and after phase change is simulated. First, the temperature-induced phase change test of the prepared unit structure VO2 and polarization converter is carried out, and the temperature-induced phase change curve of VO2 phase change material in the polarization converter can be reconstructed. Figure 11 As shown in the left figure, the temperature-induced phase change test curve of the reconfigurable converter is as follows Figure 11 As shown in the figure on the right, when the VO2 phase change material in the reconfigurable polarization converter is tested, the resistance before the phase change is 18 kΩ and the resistance after the phase change is 10 Ω. When the reconfigurable converter is tested, the single resistance before the phase change is 18 kΩ. , after phase change to .

[0058] The electro-induced phase change curve of a single-row phase change material of a reconfigurable polarization converter is shown in the figure below. Figure 12 As shown by Figure 11 and Figure 12 It can be seen that before the voltage is applied, the single resistor , when the voltage is 100 V, the resistance of a single VO2 It can be found that the resistance after the electro-induced phase transition is slightly higher than the single resistance value after the temperature-induced phase transition. This is because during the electro-induced phase transition, a conductive channel is formed in VO2, but there are still parts in VO2 that have not undergone phase transition. During the temperature-induced phase transition, the overall temperature of VO2 will exceed the phase transition temperature. In the simulation, the resistance of M-phase VO2 at room temperature and pressure is set to Res = 10 kΩ, set the high temperature and high pressure R phase VO2 to Res = 50 Ω.

[0059] When the external environment is at room temperature and pressure, VO2 is in a high-resistance state, and the polarization rate curves before and after the phase change of the polarization converter can be reconstructed as follows: Figure 13 As shown in (a) and (b), the cross-polarization rate of the designed structure is greater than 70% and the co-polarization rate is less than 10% in the 6.76-7.18 GHz band, indicating that before the VO2 phase transition, most of the incident electromagnetic wave undergoes cross-polarization after being reflected by the polarization converter. The co-polarization rate reaches a minimum at 6.81 and 7.13 GHz, near the resonance point. x Polarization and y Polarized electromagnetic waves basically achieve perfect polarization conversion.

[0060] When the temperature is higher than the VO2 phase transition temperature, VO2 transforms into the low-resistance R phase, and the reflection coefficient curve is as follows: Figure 13 As shown in (b), the cross polarization rates in both directions are almost 0, indicating that after the VO2 phase transition, the polarization converter loses its polarization conversion performance. However, it can be seen from the figure that the same polarization reflectivity is less than 1, and yPolarized electromagnetic waves have a minimum reflectivity at 6.9 GHz. This is because VO2 is equivalent to a resistor in the polarization converter. When the oscillating current passes through VO2, Joule heating effect occurs, which consumes some energy and reduces the reflection efficiency. y There is VO2 in the direction, which is y The consumption effect of polarized electromagnetic waves is more intense.

[0061] The polarization conversion rate of the reconfigurable polarization converter before and after phase change is shown in Figure 14 (a) and modulation depth are shown in Figure 14 (b) in . Figure 14 In (a), at low temperatures, the polarization conversion efficiency of the designed structure is greater than 90% at 6.69-7.11 GHz. At high temperatures, the polarization conversion efficiency is close to 0, indicating that after the VO2 phase transition, only a small amount of electromagnetic waves undergo polarization deflection. At this time, the polarization converter is a co-polarization reflective surface. Comprehensive analysis shows that under the influence of temperature or voltage, the polarization converter changes from a cross-polarization conversion reflective surface to a co-polarization reflective surface, and the polarization converter undergoes reconstruction. Figure 14 As can be seen from (b), the designed reconfigurable polarization converter has a modulation depth greater than 90% in the 6-8 GHz range.

[0062] The reconfigurable polarization converter was fabricated using printed circuit board technology. The sample, measuring 180 mm by 180 mm, consisted of 12 × 11 unit cells. To facilitate voltage loading, voltage feeders were placed along the upper and lower edges of the sample. To prevent sudden current fluctuations after phase transition from damaging the VO2, a 2 kΩ protection resistor was added to each circuit. The circuit consisted of 12 × 11 units.

[0063] The process of coating VO2 phase change material on the surface of polarization converter is as follows: first, a hollow polyimide film is made according to the converter structure design, and then the hollow polyimide film is attached to the converter surface, and the film opening is aligned with the gap position of the converter top layer where VO2 phase change material needs to be coated, and the VO2 phase change material is sprayed on the surface of the polyimide film using spraying technology. After drying, the hollow film is peeled off, and the VO2 phase change material in the hollow position remains on the surface of the polarization converter. The actual picture of the part of the unit structure after coating is as follows Figure 15 As shown, each square metal sheet has a corresponding gap at each of its four corners, and VO2 phase change material is coated in two opposite gaps (located on the same diagonal line). Figure 15 The size of the coated phase change material in the actual picture is a bit large, and part of the phase change material overflows and covers the contact piece and the extension piece. In fact, only the phase change material part within the gap is effective. The phase change material part outside the gap does not work, but it has no impact, so the overflow part is not removed in the actual product.

[0064] A polyimide heating film was attached to the back of the underlying metal reflector to heat the sample. To achieve voltage-controlled VO2 phase transition, a high-current programmable DC power supply (ITECH IT6527D) was used to apply voltage to the polarization converter. The sample was tested using an open-field method. Two identical standard horn antennas were used to transmit and receive signals, connected to an Agilent Technologies N5230A vector network analyzer. Testing was performed at 6-8 GHz. The sample was placed 3 meters directly in front of the two horn antennas, with absorbing material placed on the back to prevent environmental interference. When the transmitting and receiving antennas were aligned, the co-polarization reflection coefficient was measured. Adjusting the receiving antenna to a vertical position allowed the cross-polarization reflection coefficient to be measured.

[0065] Figure 16 Figure (a) shows the measured polarization rate curves of the reconfigurable polarization converter before and after the phase transition, while Figure (b) shows the simulated polarization rate curves of the reconfigurable polarization converter before and after the phase transition. It can be seen that the measured results are largely consistent with the simulated results, demonstrating that the performance of the polarization conversion metasurface can be reconfigured by increasing the sample temperature and applying a DC voltage.

[0066] The above tests indicate that the reconfigurable polarization converter provided by the present invention can control the working state of the converter by temperature and voltage.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A temperature-voltage-controlled reconfigurable reflective polarization converter, characterized in that: The invention comprises a bottom metal reflector, an intermediate dielectric layer, and a top resonant unit layer arranged in sequence from bottom to top. The top resonant unit layer comprises a plurality of square metal sheets, which are periodically arranged in an M×N pattern on the intermediate dielectric layer to form a periodic array. Phase change material is coated between adjacent square metal sheets. The phase change material is obtained by dispersing VO2 nanopowder in a PVP matrix. The square-shaped metal sheet is inclined at 45°, and the four sides of the square-shaped metal sheet extend outward to form an extension sheet. A contact sheet is provided at one end of the extension sheet, and the edge of the contact sheet is at 45° to the edge of the extension sheet. There is a gap between adjacent contact sheets, and phase change material is coated in two opposite gaps on each of the square-shaped metal sheets.

2. The temperature-voltage-controlled reconfigurable reflective polarization converter according to claim 1, wherein: The preparation method of the phase change material is as follows: firstly, a PVP aqueous solution is prepared, and then VO2 nanopowder is dispersed in the PVP aqueous solution to obtain the phase change material.

3. The temperature-voltage-controlled reconfigurable reflective polarization converter according to claim 2, wherein: The preparation method of the phase change material is as follows: firstly, a PVP aqueous solution with a mass fraction of 3%-10% is prepared, and then VO2 nanopowder is dispersed in the PVP aqueous solution. The volume fraction of VO2 in the phase change material is 40%-80%.

4. The temperature-voltage-controlled reconfigurable reflective polarization converter according to claim 3, wherein: The volume fraction of VO2 in the phase change material is 60%, and the volume fraction of PVP is 40%.

5. The temperature-voltage-controlled reconfigurable reflective polarization converter according to claim 1, wherein: The square metal sheet and the metal reflector are both composed of metal-clad copper, and the electrical conductivity of the metal-clad copper is σ copper =5.96×10 7 S / m, when it is greater than 1GHz, the skin depth of the metal copper is less than 2.06μm, and the thickness of the metal copper is 35μm.

6. The temperature-voltage-controlled reconfigurable reflective polarization converter according to claim 1, wherein: The plurality of square metal sheets are periodically arranged on the intermediate dielectric layer in the form of M×N to form a periodic array, wherein M≥12, N≥11, M and N are both integers, and the period p=13-16 mm.

7. The temperature-voltage-controlled reconfigurable reflective polarization converter according to claim 1, wherein: The square side length of the square metal sheet is l1 = 10-12 mm, the thickness of the gap is s2 = 0.05-0.2 mm, the length of the gap is the same as the length of the contact sheet, the length of the contact sheet is w1 = 0.3-0.7 mm, the width of the contact sheet is s1 = 0.1-0.4 mm, and the width of the extension sheet is w2 = 0.5-2 mm.

8. The temperature-voltage-controlled reconfigurable reflective polarization converter according to claim 1, wherein: The middle dielectric layer uses a high-frequency PCB circuit board with a dielectric constant of 3-5 and a loss tangent of 0.001-0.0037.

9. The temperature-voltage-controlled reconfigurable reflective polarization converter according to claim 8, wherein: The thickness of the intermediate dielectric layer is h2 = 0.5-1 mm.

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