Non-contact magnetically controlled dual-polarized reconfigurable metasurface

Abstract

The application provides a non-contact magnetic control dual-polarized reconfigurable metasurface, comprising a plurality of array distributed electromagnetic units in an external static magnetic field. The electromagnetic unit comprises a metal floor and a magnetic control dual-polarized reconfigurable structure arranged on the metal floor, and the magnetic control dual-polarized reconfigurable structure comprises a first radiation patch, a second radiation patch arranged on one side of the first radiation patch and two orthogonally arranged reed switches, one end of each reed switch is connected with the first radiation patch, and the other end of each reed switch is connected with the second radiation patch. Each reed switch can be turned on when the magnetic field of the external static magnetic field is greater than a preset conduction threshold or turned off when the magnetic field of the external static magnetic field is less than a preset disconnection threshold, so as to independently control the conduction or disconnection of each reed switch through the size of the magnetic field of the external static magnetic field, thereby realizing passive on-off control, and effectively avoiding the problems of design complexity, unstable phase response, influence on overall performance and reliability caused by using active devices for on-off control.

Description

Technical Field

[0001] This application relates to the field of wireless communication technology, and in particular to a non-contact magnetized dual-polarized reconfigurable metasurface. Background Technology

[0002] With the rapid development of 5G / 6G mobile communication and IoT technologies, wireless communication systems are facing increasingly higher requirements for spectrum efficiency, coverage, and energy efficiency. Reconfigurable Intelligent Surfaces (RIS), as an emerging technology that can dynamically adjust the direction, polarization, and signal strength of electromagnetic beams, are a key enabling technology for improving the performance of future wireless networks.

[0003] Specifically, reconfigurable smart metasurfaces consist of a large number of periodically arranged subwavelength tunable electromagnetic units, allowing for flexible manipulation of incident electromagnetic waves by independently controlling the electromagnetic response of each unit. In scenarios such as satellite communication, radar detection, and mobile communication, dual-polarization capability can significantly improve channel capacity and spectral efficiency; therefore, dual-polarized reconfigurable smart metasurfaces have become an important research direction in this field. Currently, phase modulation of dual-polarized reconfigurable smart metasurfaces often employs electrically controlled active devices such as PIN diodes, varactor diodes, or MEMS switches to switch the resonant states of the electromagnetic units.

[0004] However, electrically controlled active devices require complex DC bias networks, which increases the design complexity and profile height of the electromagnetic units. Furthermore, in arrays of very large-scale electromagnetic units, the active DC bias network can cause wiring congestion, DC voltage drop, and electromagnetic crosstalk, affecting the overall performance and reliability of the array. In addition, the high-frequency parasitic parameters of electrically controlled active devices can affect the phase response stability of the electromagnetic units in the millimeter-wave band. Summary of the Invention

[0005] The purpose of this application is to provide a non-contact magnetically controlled dual-polarized reconfigurable metasurface, which aims to solve the problems of design complexity and unstable phase adjustment caused by using electrically controlled active devices to switch the resonant state of electromagnetic units.

[0006] This application provides a non-contact magnetized dual-polarized reconfigurable metasurface, comprising multiple electromagnetic units arrayed in an external static magnetic field; The electromagnetic unit includes a metal floor and a magnetically controlled dual-polarization reconfiguration structure disposed on the metal floor. The magnetically controlled dual-polarization reconfiguration structure includes a first radiating patch, a second radiating patch located on one side of the first radiating patch, and two reed switches orthogonally arranged between the first radiating patch and the second radiating patch. One end of each reed switch is connected to the first radiating patch, and the other end of each reed switch is connected to the second radiating patch. Each of the reed switches can be turned on when the magnetic field of the external static magnetic field is greater than a preset conduction threshold, or turned off when the magnetic field of the external static magnetic field is less than a preset disconnection threshold.

[0007] In some embodiments, the cross-sections of the first radiating patch and the second radiating patch are both rectangular; The diagonal of the second radiating patch is collinear with the diagonal of the first radiating patch.

[0008] In some embodiments, the two reed switches are located on the outer side of the adjacent side of the first radiating patch and are arranged parallel to the corresponding side of the first radiating patch.

[0009] In some embodiments, the distance between the reed switch and the corresponding side ranges from 0.18 mm to 0.4 mm.

[0010] In some embodiments, the reed switch is provided with solder pads at both ends, one of the two solder pads is soldered to the first radiating patch, and the other of the two solder pads is soldered to the second radiating patch.

[0011] In some embodiments, the size of the welding pad along the axial direction of the reed switch ranges from 2.1 mm to 2.7 mm; And / or, the size of the welding pad in the radial direction of the reed switch ranges from 1 mm to 1.6 mm.

[0012] In some embodiments, the cross-sectional dimension of the first radiating patch is larger than the cross-sectional dimension of the second radiating patch.

[0013] In some embodiments, the cross-section of the first radiating patch is square, and the side length of the first radiating patch ranges from 11.6 mm to 13 mm.

[0014] In some embodiments, the cross-section of the second radiating patch is square, and the side length of the second radiating patch ranges from 1.8 mm to 2.4 mm.

[0015] In some embodiments, the metal floor, the first radiant patch, and the second radiant patch are all copper foil sheets.

[0016] The beneficial effects of this invention are: This application provides a non-contact magnetically controlled dual-polarized reconfigurable metasurface, comprising multiple electromagnetic units arrayed in an external static magnetic field. Each electromagnetic unit includes a metal ground plate and a magnetically controlled dual-polarized reconfiguration structure disposed on the metal ground plate. The magnetically controlled dual-polarized reconfiguration structure includes a first radiating patch, a second radiating patch located on one side of the first radiating patch, and two reed switches orthogonally arranged between the first and second radiating patches. One end of each reed switch is connected to the first radiating patch, and the other end of each reed switch is connected to the second radiating patch. Each reed switch can be turned on when the magnetic field of the external static magnetic field is greater than a preset on threshold or turned off when the magnetic field of the external static magnetic field is less than a preset off threshold. Thus, the on / off state of each reed switch can be independently controlled by the magnitude of the external static magnetic field, thereby achieving independent modulation of the phase and beam of the dual-polarized electromagnetic wave. Furthermore, in this application, the on / off control of the reed switch can be achieved simply by changing the magnitude of the external static magnetic field. Therefore, no external power supply is required, thus achieving passive on / off control. This effectively avoids the problems of design complexity, unstable phase response, and impact on overall performance and reliability caused by using active devices for on / off control. Attached Figure Description To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the electromagnetic unit structure of the non-contact magnetized dual-polarized reconfigurable metasurface shown in the embodiments of this application; Figure 2 This is a top view of the magnetized dual-polarization reconfiguration structure of the non-contact magnetized dual-polarization reconfigurable metasurface shown in the embodiment of this application; Figure 3 This is a schematic diagram of the structure of the non-contact magnetized dual-polarized reconfigurable metasurface shown in the embodiment of this application; Figure 4 This is a schematic diagram of the electric field distribution and current direction on the surface of the electromagnetic unit of the non-contact magnetized dual-polarized reconfigurable metasurface shown in the embodiments of this application when it is turned on and off under X-polarization excitation; Figure 5 This is a schematic diagram showing the reflection amplitude and phase response of the electromagnetic unit of the non-contact magnetically controlled dual-polarized reconfigurable metasurface when the state of the horizontal reed switch is changed under X-polarization excitation, as illustrated in the embodiments of this application. Figure 6 This is a schematic diagram of the simulation results of the non-contact magnetized dual-polarized reconfigurable metasurface under cross-polarization coupling, as shown in the embodiment of this application. Figure 7This is a schematic diagram of the phase encoding distribution of each electromagnetic unit of the non-contact magnetized dual-polarized reconfigurable metasurface shown in the embodiments of this application; Figure 8 This is a schematic diagram of the 3D far-field gain direction of the electromagnetic unit of the non-contact magnetized dual-polarized reconfigurable metasurface when the target beam is deflected by 13°, as shown in the embodiment of this application.

[0018] Figure label: 100. Non-contact magneto-controlled dual-polarized reconfigurable metasurface; 110. Electromagnetic unit; 120. Metal ground plane; 130. Magneto-controlled dual-polarized reconfigurable structure; 131. First radiating patch; 132. Second radiating patch; 133. Reed switch; 134. Solder pad. Detailed Implementation

[0019] In the embodiments of this application, the terms "first," "second," "third," "fourth," "fifth," and "sixth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," "third," "fourth," "fifth," and "sixth" may explicitly or implicitly include one or more of that feature.

[0020] In embodiments of this application, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0021] Reference Figures 1 to 3 As shown, this embodiment provides a non-contact magneto-controlled dual-polarized reconfigurable metasurface 100, which includes multiple electromagnetic units 110 arrayed in an external static magnetic field.

[0022] The electromagnetic unit 110 includes a metal floor 120 and a magnetically controlled dual-polarization reconfiguration structure 130 disposed on the metal floor 120. The magnetically controlled dual-polarization reconfiguration structure 130 includes a first radiating patch 131, a second radiating patch 132 located on one side of the first radiating patch 131, and two reed switches 133 orthogonally arranged between the first radiating patch 131 and the second radiating patch 132. One end of each reed switch 133 is connected to the first radiating patch 131, and the other end of each reed switch 133 is connected to the second radiating patch 132.

[0023] Each reed switch 133 can be turned on when the magnetic field of the external static magnetic field is greater than the preset conduction threshold or turned off when the magnetic field of the external static magnetic field is less than the preset disconnection threshold.

[0024] In specific implementation, the non-contact magnetically controlled dual-polarized reconfigurable metasurface 100 of this embodiment is composed of a large number of electromagnetic units 110 arranged periodically in an array. The non-contact magnetically controlled dual-polarized reconfigurable metasurface 100 is arranged within the range of an external static magnetic field. The working state of the reed switch 133 of each electromagnetic unit 110 is independently controlled in a non-contact manner by relying on the external static magnetic field. Therefore, no wiring or DC power supply is required, thus achieving a passive design.

[0025] For example, the overall array model is as follows: Figure 3 As shown, for example, it can be set up to consist of 25×25 units arranged in a period of 16 mm×16 mm, with a total array size of 400 mm×400 mm.

[0026] For example, the non-contact magnetized dual-polarized reconfigurable metasurface 100 in this embodiment is a reflective structure with an operating center frequency of 2.4 GHz. Specifically, the metal ground plane 120 serves as the bottom common ground reflective layer of the electromagnetic unit 110, acting as electromagnetic wave reflection shielding, impedance reference, and electromagnetic isolation. For example, the metal ground plane 120 can be of the Rogers RT6010 type, or it can be of the Taconic series or FR4, etc., with a relative permittivity of 10.2, a loss tangent of 0.0023, and a thickness of 3.5 mm.

[0027] Specifically, the magnetically controlled dual-polarization reconfiguration structure 130 is disposed above the metal floor 120 to realize independent phase reconstruction of dual polarization and control of electromagnetic wave beam. In this embodiment, the magnetically controlled dual-polarization reconfiguration structure 130 consists of three parts: a first radiating patch 131, a second radiating patch 132, and two orthogonally arranged reed switches 133. The second radiating patch 132 is disposed on one side of the first radiating patch 131, and the two are separate and not directly connected, relying on the reed switches 133 to establish a controllable electrical path and an electromagnetic coupling path.

[0028] For example, each electromagnetic unit 110 is provided with such Figure 1 The two reed switches 133 shown are arranged orthogonally to accommodate the X-polarization and Y-polarization orthogonal linear polarization operating modes in mobile communication, satellite communication, and radar detection. Specifically, each reed switch 133 is connected across the first radiating patch 131 and the second radiating patch 132, with one end of the reed switch 133 electrically connected to the first radiating patch 131 and the other end of the reed switch 133 electrically connected to the second radiating patch 132.

[0029] It should be noted that the reed switch 133, as a controllable RF switch, can switch between on and off states under the control of the magnitude of the external static magnetic field. This alters the current path, equivalent electrical length, and resonant boundary conditions between the first radiating patch 131 and the second radiating patch 132, thereby changing the reflection phase and polarization response of the electromagnetic unit 110 to the incident electromagnetic wave. Furthermore, as a mechanical contact switch, the reed switch 133, compared to semiconductor active devices, has lower on-resistance, smaller off-resistance parasitic capacitance, weaker high-frequency parasitic effects, and better phase response stability, making it more suitable for high-frequency applications such as millimeter waves. Simultaneously, the reed switch 133's control method is simple, reliable, and highly resistant to interference. Using the magnitude of the external static magnetic field as the sole control condition, it is free from active circuit noise and power supply fluctuations, resulting in more stable and reliable state switching.

[0030] For example, the reed switch 133 can be of model RI-80, which is a single-pole single-throw normally open magnetic switch that achieves non-contact state switching through an external static magnetic field. The reed switch 133 closes and conducts when the magnetic field is greater than 150 Gauss and opens when the magnetic field is less than 20 Gauss. That is, the preset conduction threshold is 150 Gauss and the preset opening threshold is 20 Gauss. Alternatively, other reed switches of different models or other magnetic switching devices can be used instead, achieving the same effect of magnetically controlled non-contact actuation.

[0031] To obtain accurate electromagnetic characteristics of the reed switch 133 in the radio frequency band, the TRL calibration method can be used for de-embedding measurements to directly extract the S-parameters of both ends of the reed switch 133. Experimental results show that the reed switch 133 has stable amplitude and phase characteristics within the operating frequency band. Equivalent circuit fitting of the measured S-parameters yields the following: near 2.45 GHz, the on-state is equivalent to a series circuit with R = 4.591Ω, C = 20 pF, and L = 4.923 nH, and the off-state is equivalent to a series circuit with R = 0.1Ω, C = 0.4644 pF, and L = 4.08 nH.

[0032] The specific on / off control principle of the reed switch 133 is briefly described as follows: When the magnetic field strength of the external static magnetic field is greater than the preset conduction threshold, the reed inside the reed switch 133 is magnetized and attracted, so that the reed switch 133 is in the conduction state. At this time, the first radiating patch 131 and the second radiating patch 132 form a low-resistance connection path, and the electromagnetic unit 110 corresponds to a resonance state and reflection phase.

[0033] When the magnetic field strength of the external static magnetic field is less than the preset disconnection threshold, the reed inside the reed switch 133 loses its magnetism and separates. At this time, the reed switch 133 is in the disconnected state. The DC path between the first radiating patch 131 and the second radiating patch 132 is cut off. The induced current can only travel around the edge of the first radiating patch 131 or be capacitively coupled through the gap between the first radiating patch 131 and the second radiating patch 132. The equivalent electrical length of the electromagnetic unit 110 changes, and then switches to another resonant state and reflection phase.

[0034] Specifically, the working mechanism of the electromagnetic unit 110 in this embodiment can be intuitively explained from its physical structure and field distribution. Specifically, after the electromagnetic wave from the external static magnetic field enters free space, it excites an induced current between the metal floor 120 and the first radiating patch 131, which is then reflected by the metal floor 120 and re-radiated. The key to controlling the reflection phase lies in the current path formed by the first radiating patch 131 and the reed switch 133. For example, when the above-mentioned type of reed switch 133 is used, for X-polarized excitation, when the external static magnetic field is greater than 150 Gauss, such as... Figure 1 The reed switch 133, placed horizontally along the X-direction, is closed and conducting. A short direct current path is formed between the first radiating patch 131 and the second radiating patch 132 via the reed switch 133. At this point, the equivalent inductance is small, and the electromagnetic unit 110 resonates around 2.45 GHz. When the external static magnetic field is less than 20 Gauss, the reed switch 133 is opened, the direct current path is cut off, and the induced current is forced to travel along the longer edge of the first radiating patch 131 and couple to the second radiating patch 132 via the gap capacitance between the first radiating patch 131 and the reed switch 133. The equivalent electrical length increases, and the resonant frequency shifts towards around 2.6 GHz.

[0035] Furthermore, in this embodiment, by optimizing the spacing between the first radiating patch 131 and the reed switch 133, the resonant frequencies in both states are symmetrically distributed on both sides of the design frequency, thereby obtaining a reflection phase difference of approximately 140° at 2.45 GHz, satisfying the 180° ± 37° response required for 1-bit phase modulation. The reflection coefficient amplitude remains within -4.5 dB in both states, indicating that the electromagnetic unit 110 has low-loss characteristics. Similarly, the on / off state of the vertically placed reed switch 133 along the Y direction independently controls the current path under Y-polarized excitation, realizing 1-bit phase modulation of Y-polarization.

[0036] As described above, in this embodiment, by controlling the threshold strength of the external static magnetic field, the two electromagnetic states of each electromagnetic unit 110 can be flexibly switched without contact or passivity, thereby achieving 1-bit phase reconstruction. The surface of the electromagnetic unit 110 requires no DC bias lines, metallized vias, or choke structures. A truly passive reconfigurable metasurface is achieved in the minimalist configuration formed by the metal ground plane 120 and the magnetically controlled dual-polarization reconstruction structure 130. This fundamentally avoids the dependence on complex active bias networks in traditional electronic control schemes, significantly reducing the complexity of the electromagnetic unit 110 and the manufacturing cost of large-scale arrays. Furthermore, the reed switch 133, as a magnetically sensitive element, integrates "magnetic field sensing" and "switching execution," directly responding to changes in the external magnetic field without intermediate conversion circuits. This enables the electromagnetic unit 110 to possess in-situ sensing and response capabilities to magnetic field encoded signals under passive conditions.

[0037] It should be noted that this embodiment employs a design with two orthogonally arranged reed switches 133. One reed switch 133 corresponds to horizontal polarization in the X direction, and the other reed switch 133 corresponds to vertical polarization in the Y direction. The two current excitation paths are spatially orthogonal. The two orthogonally arranged reed switches 133 are each independently connected between the first radiating patch 131 and the second radiating patch 132 without interfering with each other. The phase response of the two orthogonally polarized electromagnetic waves can be independently controlled, thereby achieving independent dual-polarization control, high polarization isolation, and avoiding crosstalk between polarizations.

[0038] In summary, this embodiment sets up a magnetically controlled dual-polarization reconfiguration structure 130, and controls the reed switches 133 of the magnetically controlled dual-polarization reconfiguration structure 130 to open or close under the influence of the magnitude of the external static magnetic field. This eliminates the need for active electronic control devices such as PIN diodes, varactor diodes, and MEMS switches used in the prior art. Therefore, there is no need to design complex DC bias networks, metallized vias, or multi-layer power supply wiring, thus fundamentally solving the problems of wiring congestion, DC voltage drop, and electromagnetic crosstalk caused by the use of active electronic control devices in the prior art.

[0039] Furthermore, in this embodiment, the reed switch 133 achieves on / off control solely by the threshold drive of the external static magnetic field, thereby realizing non-contact regulation. The electromagnetic unit 110 itself has no DC power consumption and requires no power supply lines or control leads, which makes the array layout of the electromagnetic unit 110 simple and facilitates large-scale expansion and integration.

[0040] Furthermore, the orthogonal arrangement of two reed switches 133 ensures that the two polarization current paths are spatially orthogonal, enabling independent 1-bit phase control of X and Y dual polarizations. This achieves high isolation for independent dual polarization control, with low crosstalk between polarizations and excellent isolation, making it suitable for dual polarization applications in 5G / 6G communication, satellite communication, and radar detection. In addition, the electromagnetic unit 110, relying on the minimalist configuration of the metal ground plane 120, dual-radiating patch, and orthogonal reed switches 133, reduces the number of switching elements required for dual polarization 1-bit phase control to a theoretical minimum of two. This avoids the design dilemma in existing solutions where reducing the number of switches requires increasing the number of wiring layers, thus significantly reducing the complexity of the electromagnetic unit 110 and the manufacturing cost of large-scale arrays.

[0041] Furthermore, the mechanical contact characteristics of the reed switch 133 endow it with extremely low on-resistance and minimal off-resistance, giving it a natural advantage in low loss at high frequencies compared to PIN diodes, making it more suitable for expansion into higher frequency bands such as millimeter waves. This structure provides an effective technical approach for constructing low-cost, easily scalable, and high-frequency applicable large-scale reconfigurable electromagnetic protection arrays.

[0042] Reference Figure 1 and Figure 2 As shown, in some embodiments, the cross-sections of the first radiating patch 131 and the second radiating patch 132 are both rectangular; the diagonal of the second radiating patch 132 is collinear with the diagonal of the first radiating patch 131.

[0043] In specific implementation, the first radiating patch 131 is the main radiator under X-polarization and Y-polarization excitation, which determines the fundamental resonant frequency of the electromagnetic unit 110. The second radiating patch 132 mainly serves as an electrical common connection node, affecting impedance matching and phase linearity. In this embodiment, both the first radiating patch 131 and the second radiating patch 132 adopt a regular rectangular cross-sectional structure, making their shape regular and their geometric boundaries clear, which is convenient for electromagnetic simulation modeling and fabrication.

[0044] In this embodiment, the second radiating patch 132 is arranged on one side of the first radiating patch 131, and their diagonals are on the same straight line, i.e., referring to... Figure 1 As shown, the first radiating patch 131 is located in the upper left quadrant of the second radiating patch 132, thus forming an "L-shaped" layout. This layout makes the first radiating patch 131 and the second radiating patch 132 form an alignment reference at the geometric center, the electric field distribution center, and the electromagnetic coupling center. The gap between the first radiating patch 131 and the second radiating patch 132 is symmetrically distributed along the diagonal, so that the coupling path of the induced current between the first radiating patch 131 and the second radiating patch 132 is symmetrically distributed. Therefore, there will be no one-sided bias, electric field distortion, or current path asymmetry.

[0045] Alternatively, the first radiating patch 131 can be located in other quadrants of the second radiating patch 132, such as the upper right, lower left, or lower right, or the entire magnetized dual-polarization reconstructed structure 130 can be rotated by 90°, 180°, or 270°, with its function being completely equivalent to the original structure.

[0046] In other words, the diagonal collinear layout makes the electromagnetic coupling of the first radiating patch 131 and the second radiating patch 132 symmetrical, and the surface electric field and induced current distribution of the electromagnetic unit 110 are regular and balanced, which can effectively suppress stray electric fields at the edges and asymmetric parasitic coupling, and improve the consistency of electromagnetic response under dual polarization operation.

[0047] Furthermore, the orthogonally arranged reed switches 133 are connected between the first radiating patch 131 and the second radiating patch 132. Based on the regular rectangular shape of the first radiating patch 131 and the second radiating patch 132 and their collinear symmetrical layout, the installation position, parallelism and bridging span of the reed switches 133 can be precisely defined, ensuring that the two orthogonal reed switches 133 are arranged in a standardized manner and with consistent spacing, thus providing a stable structural foundation for realizing independent control of two polarization paths.

[0048] Reference Figures 1 to 2 As shown, in some embodiments, two reed switches 133 are located on the outer side of the adjacent side of the first radiating patch 131, and are arranged parallel to the corresponding side of the first radiating patch 131.

[0049] In a specific implementation, the first radiating patch 131 has a rectangular outline and two adjacent, mutually perpendicular sides. The two reed switches 133 are respectively arranged in the outer regions of these two adjacent sides, without intruding into the outline of the first radiating patch 131.

[0050] Furthermore, the length of each reed switch 133 is parallel to its corresponding side, and the reed switches 133 are arranged in a straight line along the edge without tilting or shifting.

[0051] Since the two adjacent sides of the rectangular first radiating patch 131 are geometrically orthogonal to each other, and the two reed switches 133 are arranged parallel to the two orthogonal adjacent sides, the two reed switches 133 automatically form a 90° orthogonal layout in space without the need for additional angle correction, so as to meet the orthogonal structure conditions required for dual polarization.

[0052] Furthermore, the parallel side arrangement of the reed switch 133 allows it to be arranged along the main direction of the induced current at the edge of the first radiating patch 131. One reed switch 133 is parallel to the horizontal side, corresponding to the horizontal X-polarized current path, and the other reed switch 133 is parallel to the vertical side, corresponding to the vertical Y-polarized current path. This ensures that the current flow direction is consistent with the axis of the reed switch 133, thereby making the radio frequency current transmission smooth and reducing corner distortion and impedance abrupt changes.

[0053] In some embodiments, the distance between the reed switch 133 and the corresponding side ranges from 0.18 mm to 0.4 mm.

[0054] In this embodiment, the spacing refers to the vertical net distance between the outer wall of the reed switch 133 and the corresponding side of the first radiating patch 131. It is the isolation gap when the two are arranged in parallel and is a key parameter for adjusting the phase difference between the two states of the reed switch 133.

[0055] Specifically, if the spacing is too large, the electromagnetic coupling strength is significantly weakened, and the ability of the reed switch 133 to control the surface induced current of the first radiating patch 131 becomes weaker. Simultaneously, the equivalent electrical length change of the reed switch 133 in both on and off states is insufficient, making it impossible to form the approximately 180° phase difference required for 1-bit control. If the spacing is too small, the edges of the reed switch 133 and the first radiating patch 131 are too close, and the strong electric fields at the edges couple with each other, generating excessive parasitic capacitance. Furthermore, a small spacing also introduces additional stray resonant points, causing a shift in the operating frequency and increased reflection loss.

[0056] For example, the distance between the reed switch 133 and the corresponding side can be 0.18 mm, 0.2 mm, or 0.4 mm.

[0057] In some embodiments, the two ends of the reed switch 133 are respectively provided with solder pads 134, one of the two solder pads 134 is soldered to the first radiating patch 131, and the other of the two solder pads 134 is soldered to the second radiating patch 132.

[0058] In specific implementation, the two ends of the reed switch 133 in the axial direction are not directly connected to the first radiating patch 131 and the second radiating patch 132 through bare pins. Instead, dedicated solder pads 134 are pre-laid as transitional connection structures between the pins of the reed switch 133 and the first radiating patch 131 and the second radiating patch 132. The solder pads 134 are soldered to the corresponding first radiating patch 131 or second radiating patch 132 to achieve electrical conduction.

[0059] Specifically, the pins of one end of the reed switch 133 are soldered to the corresponding solder pad 134, which is connected to the first radiating patch 131. The pins of the other end of the reed switch 133 are soldered to the corresponding solder pad 134, which is connected to the second radiating patch 132, thereby forming a complete controllable radio frequency electrical path from the first radiating patch 131 to the solder pad 134 to the reed switch 133 to the solder pad 134 to the second radiating patch 132.

[0060] Reference Figure 2 As shown, in some embodiments, the size of the solder pad 134 along the axial direction of the reed switch 133 ranges from 2.1 mm to 2.7 mm; the size of the solder pad 134 along the radial direction of the reed switch 133 ranges from 1 mm to 1.6 mm.

[0061] By reasonably setting the dimensional range of the welding pad 134 in the axial and radial directions of the reed switch 133, the requirements of welding reliability and avoiding impact on electrical performance can be balanced.

[0062] Specifically, refer to Figure 2 As shown, if the axial dimension b is too small, the overlap length of the solder pad 134 will be too short, resulting in insufficient soldering area and making it easy for issues such as cold solder joints and detachment to occur, affecting soldering reliability. If the axial dimension b is too large, the solder pad 134 will extend excessively along the axial direction, occupying the effective area of ​​the electromagnetic unit 110, thereby generating additional parasitic capacitance and stray electromagnetic coupling, interfering with the original resonant characteristics of the first radiating patch 131 and the second radiating patch 132, causing frequency shift and phase response distortion.

[0063] Specifically, if the radial dimension 'a' is too large, the solder pad 134 will be too wide laterally, which will intensify the useless coupling with the first radiating patch 131, the second radiating patch 132, and the adjacent reed switch 133, thus deteriorating the polarization isolation and loss characteristics. If the radial dimension 'a' is too small, the solder pad 134 will be too narrow, making soldering difficult in the process.

[0064] For example, in this embodiment, the axial dimension b of the solder pad 134 along the reed switch 133 can be 2.1 mm, 2.5 mm, or 2.7 mm. The radial dimension a of the solder pad 134 along the reed switch 133 can be 1 mm, 1.3 mm, 1.4 mm, or 1.6 mm.

[0065] Reference Figure 1 and Figure 2 As shown, in some embodiments, the cross-sectional dimension of the first radiating patch 131 is larger than the cross-sectional dimension of the second radiating patch 132.

[0066] Specifically, in this embodiment, the first radiating patch 131 serves as the main radiating resonator, undertaking the core functions of receiving incident electromagnetic waves, reflecting resonance, and constructing the basic current path; therefore, its size is relatively large. The second radiating patch 132 does not participate in the dominant resonance but only serves as a common electrical relay node for the two orthogonal reed switches 133, connecting the other ends of the two reed switches 133 and acting as an electrical bridge; therefore, its size can be designed to be smaller.

[0067] In some embodiments, the cross-section of the first radiating patch 131 is square, and the side length of the first radiating patch 131 ranges from 11.6 mm to 13 mm.

[0068] In practice, the first radiating patch 131 adopts a square cross-section. The square cross-section is geometrically symmetrical in two orthogonal directions, horizontal and vertical, so that the X polarization and Y polarization have similar resonant frequencies, radiation impedances and current distributions, in order to meet the requirements of dual-polarization symmetrical operation.

[0069] Furthermore, if the side length L1 is less than 11.6 mm, the resonant frequency of the first radiating patch 131 will be too high, which will deviate from the design operating frequency and result in insufficient electrical length to form a sufficient phase difference. If the side length L1 is greater than 13 mm, the size of the first radiating patch 131 will be too large, exceeding the subwavelength constraint, which will easily generate high-order stray resonances and lead to performance degradation.

[0070] Therefore, by setting the side length L1 of the first radiating patch 131 in the range of 11.6mm to 13mm, the fundamental resonant frequency can be precisely locked, and the resonant points of the reed switch 133 in both the on and off states can be symmetrically distributed, making it easy to achieve the phase difference required for 1-bit phase modulation.

[0071] For example, the side length L1 of the first radiating patch 131 can be 11.6mm, 12mm, 12.5mm or 13mm.

[0072] In some embodiments, the cross-section of the second radiating patch 132 is square, and the side length of the second radiating patch 132 ranges from 1.8mm to 2.4mm.

[0073] In practice, the second radiating patch 132 also adopts a square structure, which makes the electrical characteristics uniform in all directions. As a common connection node, it can evenly distribute the induced current of the two orthogonal reed switches 133, and will not cause the polarization response of the two paths to be unbalanced due to the asymmetrical shape.

[0074] Furthermore, if its side length L2 is less than 1.8mm, making its area too small, it will result in insufficient space for the arrangement of the solder pad 134, making soldering difficult and prone to incomplete soldering, which in turn leads to poor electrical connection reliability.

[0075] If its side length L2 is greater than 2.4mm, making its size too large, it will lead to enhanced parasitic capacitance and edge coupling, which will easily introduce additional electromagnetic interference and destroy the original resonant characteristics of the electromagnetic unit 110.

[0076] Therefore, setting the side length L2 of the second radiating patch 132 within the range of 1.8mm-2.4mm can not only meet the welding layout requirements of the reed switch 133, but also control the parasitic electromagnetic parameters at an extremely low level.

[0077] For example, the side length L2 of the second radiating patch 132 can be 1.8 mm, 2 mm or 2.4 mm.

[0078] Alternatively, in other implementations, the first radiating patch 131 and the second radiating patch 132 can also be irregular shapes such as circles, ellipses, or polygons to adjust the frequency response and impedance matching characteristics.

[0079] In some embodiments, the metal floor 120, the first radiating patch 131, and the second radiating patch 132 are all copper foil sheets.

[0080] It should be noted that the metal floor 120, the first radiating patch 131, and the second radiating patch 132 are all made of copper foil material and etched into shape.

[0081] Copper foil possesses physical properties such as high conductivity, low surface roughness, low high-frequency microwave loss, good ductility, and strong adhesion, making it ideal for resonant radiation and radio frequency current transmission. Furthermore, copper foil processing is mature, offers high etching precision, and has controllable costs, making it suitable for large-area array mass production.

[0082] also, Figure 4 The electric field distribution and current direction on the surface of the electromagnetic unit 110 are shown under X-polarized excitation, during the on and off states of the reed switch 133. Figure 4 It can be seen that in the on state, a large current is induced in the reed switch 133 and flows in the horizontal direction (i.e., the X direction). In the off state, the central direct current path is cut off, and the current is forced to bypass the edge of the first radiating patch 131.

[0083] It should be noted that the electric field and current distribution under Y-polarization excitation exhibit similar orthogonal duality characteristics. Since the dominant current paths corresponding to the two polarizations are orthogonal to each other in space, the second radiating patch 132, as a common node, has orthogonal superposition of current flows under the excitation of the two polarizations without generating energy crosstalk. The electromagnetic unit 110 has an inherent high polarization isolation, and the switching of a polarization state has minimal impact on the electromagnetic response of the orthogonal polarization, thus realizing true independent dual-polarization control.

[0084] Furthermore, to verify the dual-polarization independent control performance of the electromagnetic unit 110, the unit was modeled and analyzed using electromagnetic simulation software, and the environment of an infinitely large periodic array was simulated using Floquet port excitation and master-slave boundary conditions. Figure 5 This demonstrates the reflection amplitude and phase response of the electromagnetic unit 110 when only the state of the horizontally placed reed switch 133 is changed under X-polarization excitation. Figure 5 It can be seen that the reflection coefficient amplitude remains within -4.5 dB in both states, and the reflection phase difference is approximately 140° at the operating frequency of 2.45 GHz. Similarly, the simulation results under Y-polarized excitation exhibit similar characteristics.

[0085] Furthermore, Figure 6 Simulation results of cross-polarization coupling are presented, and the isolation between the two polarization channels is evaluated through the cross-polarization transfer coefficient. When only the state of the vertically placed reed switch 133 is changed under X-polarization excitation, the cross-polarization transfer coefficient remains at an extremely low level, indicating that the switching action of the Y-polarization channel has almost no effect on the X-polarization electromagnetic response; and vice versa. This result fully verifies that the electromagnetic unit 110 has excellent dual-polarization independent control capability and high polarization isolation.

[0086] Furthermore, unlike traditional active control, the non-contact magnetically controlled dual-polarized reconfigurable metasurface 100 in this embodiment does not require the use of PIN diodes or varactor diodes to achieve resonant tuning via bias voltage. Instead, it switches its operating state under different external static magnetic fields. Structurally, the control of both polarization directions does not require any DC bias circuit design; only two orthogonally placed reed switches 133 are needed to achieve truly passive non-contact on / off control. The electromagnetic unit 110 itself is a passive structure with zero DC power consumption. In terms of driving mode, the electromagnetic scattering fields of the two polarizations are independently modulated by an external static magnetic field, making the control method simple and reliable.

[0087] It is worth noting that the reed switch 133 itself is a magnetic field sensitive element. Its reed is directly magnetized under the action of an external magnetic field and produces a mechanical closing action, integrating the functions of "magnetic field sensing" and "switching execution" into one, without the need for additional magneto-electric conversion circuits or sensor modules, thus achieving in-situ direct response to magnetic field signals. This characteristic distinguishes this embodiment from other mechanical or optically controlled passive switch solutions. Although the latter can also achieve passive control, they require additional force transmission mechanisms or photoelectric conversion units, making it difficult to achieve compact integration within subwavelength scale metasurface units. From an application perspective, the magnetic control solution does not need to consider DC bias power supply and power consumption requirements, and there are no problems such as wiring congestion, DC voltage drop, and electromagnetic crosstalk in large-scale arrays.

[0088] Figure 7The array phase coding distribution diagram generated by MATLAB is shown. The continuous phase is discretized into the on or off state of the corresponding reed switch 133 by the 1-bit quantization criterion. The phase distribution is calculated independently for X polarization and Y polarization respectively, and the coding state of the corresponding reed switch 133 in each electromagnetic unit 110 is determined.

[0089] Figure 8 The 3D far-field gain pattern of the entire array when the target beam is deflected by 13° clearly shows that the reflected beam forms a distinct main gain lobe in the direction of the predetermined deflection angle, verifying the effective control capability of the array's 1-bit quantization coding scheme for beam pointing. Further simulations demonstrate that by dynamically adjusting the coding states of the two reed switches 133 in each electromagnetic unit 110 of the array, the reflected beam can be flexibly controlled within a certain angle range, verifying the feasibility of this embodiment in passive, non-contact, reconfigurable electromagnetic beam control applications.

[0090] The non-contact magnetically controlled dual-polarized reconfigurable metasurface 100 achieves independent 1-bit phase modulation and reconfigurable beam control of dual polarization under power-free conditions through magnetic programming and reconfiguration. In principle, it solves the prominent problems faced by traditional electrically controlled dual-polarized metasurfaces in large-scale array layout, such as complex bias circuit design, wiring congestion and DC power consumption.

[0091] In the description of the embodiments of this application, specific features, structures, materials or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0092] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A contactless magnetically controlled dual-polarized reconfigurable metasurface, characterized in that, It includes multiple electromagnetic units (110) arrayed in an external static magnetic field. The electromagnetic unit (110) includes a metal floor (120) and a magnetically controlled dual-polarization reconfiguration structure (130) disposed on the metal floor (120). The magnetically controlled dual-polarization reconfiguration structure (130) includes a first radiating patch (131), a second radiating patch (132) located on one side of the first radiating patch (131), and two reed switches (133) orthogonally arranged between the first radiating patch (131) and the second radiating patch (132). One end of each reed switch (133) is connected to the first radiating patch (131), and the other end of each reed switch (133) is connected to the second radiating patch (132). Each of the reed switches (133) can be turned on when the magnetic field of the external static magnetic field is greater than a preset conduction threshold or turned off when the magnetic field of the external static magnetic field is less than a preset disconnection threshold.

2. The contactless magneto-dielectric dual-polarized reconfigurable metasurface of claim 1, wherein, The cross-sections of the first radiating patch (131) and the second radiating patch (132) are both rectangular; The diagonal of the second radiating patch (132) is collinear with the diagonal of the first radiating patch (131).

3. The contactless magneto-dielectric dual-polarized reconfigurable metasurface of claim 2, wherein, The two reed switches (133) are located on the outer side of the adjacent side of the first radiating patch (131) and are arranged parallel to the corresponding side of the first radiating patch (131).

4. The contactless magneto-dielectric dual-polarized reconfigurable metasurface of claim 3, wherein, The distance between the reed switch (133) and the corresponding side is in the range of 0.18mm-0.4mm.

5. The contactless magneto-dielectric dual-polarized reconfigurable metasurface of claim 1, wherein, The reed switch (133) is provided with welding pads (134) at both ends. One of the two welding pads (134) is welded to the first radiating patch (131), and the other of the two welding pads (134) is welded to the second radiating patch (132).

6. The non-contact magnetized dual-polarized reconfigurable metasurface according to claim 5, characterized in that, The size of the welding pad (134) along the axial direction of the reed switch (133) ranges from 2.1 mm to 2.7 mm; And / or, the size of the welding pad (134) in the radial direction along the reed tube (133) ranges from 1 mm to 1.6 mm.

7. The non-contact magnetized dual-polarized reconfigurable metasurface according to any one of claims 1 to 6, characterized in that, The cross-sectional dimension of the first radiating patch (131) is larger than the cross-sectional dimension of the second radiating patch (132).

8. The contactless magneto-dielectric dual-polarized reconfigurable metasurface of claim 7, wherein, The first radiating patch (131) has a square cross-section and the side length of the first radiating patch (131) ranges from 11.6 mm to 13 mm.

9. The contactless magneto-dielectric dual-polarized reconfigurable metasurface of claim 7, wherein, The second radiating patch (132) has a square cross-section and the side length of the second radiating patch (132) ranges from 1.8mm to 2.4mm.

10. The contactless magnetically controlled dual-polarization reconfigurable metasurface of any one of claims 1 to 6, wherein, The metal floor (120), the first radiant patch (131) and the second radiant patch (132) are all copper foil sheets.

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