Building window glass sheet on convergence metasurface for satellite communication and application method

Abstract

This application provides a converging metasurface on architectural window glass for satellite communication and its application method. The converging metasurface includes a dielectric substrate, a first metal layer, and a second metal layer. The first metal layer includes several phase modulation structures arranged in a two-dimensional periodic array. The phase modulation structures are axisymmetric S-shaped metal patches. The second metal layer serves as a continuous reflector plate to reflect the incident satellite microwave signal back to the first metal layer, thereby cooperating with the phase modulation structures to achieve polarization reversal and geometric phase modulation, ultimately passively converging the signal to the near-field focus. This application utilizes a continuous reflector plate to reflect satellite signals to an S-shaped metal patch array, achieves polarization reversal through the axisymmetric structure, and introduces geometric phase shift by relying on the independent rotation angle of each unit to form a spatial gradient distribution, precisely modulating the wavefront, and ultimately passively converging diffuse electromagnetic energy to the near-field focus, achieving efficient signal collection on the glass surface.

Description

Technical Field

[0001] This application belongs to the field of antenna technology and artificial electromagnetic metamaterials technology, and more specifically, relates to a converging metasurface on a building window glass sheet for satellite communication. Background Technology

[0002] In recent years, artificial electromagnetic metasurfaces have attracted widespread attention due to their flexible control over the amplitude, phase, and polarization state of electromagnetic waves. These materials can achieve multi-dimensional manipulation of electromagnetic waves by periodically arranging resonant units with specific geometric configurations on a subwavelength scale. Compared to traditional technologies, metasurfaces offer significant advantages such as lightweight and thin structures and ease of fabrication, demonstrating important application potential in various fields including beamforming, stealth technology, and wireless communication.

[0003] Currently, with the rapid development of technologies such as Ku-band low-Earth orbit satellite communication, satellite communication frequency bands are gradually expanding into the high-frequency range of 10.5 GHz to 12.5 GHz. However, the high-density tempered glass or double-glazed windows widely used in modern buildings have a strong reflection and attenuation effect on these high-frequency microwave signals, resulting in widespread signal coverage blind spots in indoor spaces. At the same time, existing outdoor satellite receiving devices are usually large in size, making it difficult to achieve conformal integration with building exterior walls or glass curtain walls.

[0004] In existing metasurface technologies, whether transmissive or reflective, research focuses primarily on anomalous deflection or long-distance focusing of far-field beams in space. However, to directly transform architectural glass itself into a highly efficient signal receiving carrier, there is an urgent need for an on-chip focusing technology capable of guiding and converging large-area captured spatial electromagnetic energy to a specific area (such as the central region) on the glass surface. Summary of the Invention

[0005] The purpose of this application is to provide a converging metasurface on a building window glass pane for satellite communication, so as to solve the technical problems of the large size of traditional satellite receiving antennas and the difficulty of high-frequency microwave signals penetrating modern building glass in the prior art.

[0006] To achieve the above objectives, the technical solution adopted in this application is as follows: a converging metasurface on a building window glass sheet for satellite communication is provided, comprising a dielectric substrate, a first metal layer, and a second metal layer; the first metal layer includes a plurality of phase modulation structures arranged in a two-dimensional periodic array, wherein the phase modulation structure is an axisymmetric S-shaped metal patch; the second metal layer serves as a continuous reflection substrate for reflecting incident satellite microwave signals back to the first metal layer, thereby cooperating with the phase modulation structure to achieve polarization reversal and geometric phase modulation, ultimately passively converging the signal to the near-field focus.

[0007] Furthermore, the S-shaped metal patches located at different array positions have different in-plane rotation angles; a Cartesian coordinate system is established with the center of the metasurface array as the origin, and the in-plane rotation angle of the S-shaped metal patch exhibits a specific spatial gradient distribution with respect to its coordinate position; the spatial gradient distribution is used to reflect and converge incident circularly polarized satellite microwave signals with a specific rotation direction to a near-field focal point close to the surface of the first metal layer.

[0008] Furthermore, each of the phase control structures independently constructs a local three-dimensional Cartesian coordinate system: with the center of the local region of the dielectric substrate where the phase control structure is located as the origin, and the thickness direction of the dielectric substrate as the Z-axis, the first metal layer and the second metal layer are both parallel to the XY plane; with one axis of symmetry of the S-shaped metal patch as the rotation reference, the axis of symmetry is deflected by an angle θ relative to the X-axis of the local three-dimensional Cartesian coordinate system; when a circularly polarized electromagnetic wave of a specific rotation direction is incident perpendicularly and reflected by the second metal layer, the phase control structure introduces a geometric phase shift of 2θ for the reflected electromagnetic wave through the rotation angle θ of its S-shaped metal patch, thereby realizing independent control of the unit-level phase.

[0009] Furthermore, a global two-dimensional Cartesian coordinate system X is established on the plane containing the entire metasurface array. Y, located in the array at coordinates Rotation angle of the S-shaped metal patch at the location It satisfies the following distribution pattern: ; Wherein, λ is the free space wavelength corresponding to the center frequency of the incident satellite microwave signal; The preset focusing distance; The initial constant phase is arbitrary; the focusing distance F is set to a near-field focal distance less than a set threshold, so that the reflected electromagnetic waves converge and converge close to the surface of the first metal layer.

[0010] Furthermore, the S-shaped metal patch includes: two symmetrically arranged semi-circular metal strips and an inclined metal connecting rod. The two symmetrically arranged semi-circular metal strips together form an intermittent ring with two symmetrical openings. The two ends of the metal connecting rod pass through the two openings respectively and are connected to the inner edges of the two metal strips respectively. The metal strips and the metal connecting rod together form a centrally symmetrical S-shaped pattern.

[0011] Furthermore, the dielectric substrate is a transparent glass plate.

[0012] Furthermore, both the first metal layer and the second metal layer are made of conductive thin films with a sheet resistance of less than 3Ω.

[0013] This application also provides a method for applying a converging metasurface on a building window pane for satellite communication as described above, including attaching the converging metasurface to the surface of an exterior window of a building; using a second metal layer to reflect incident outdoor satellite microwave signals; and passively converging the satellite microwave signals to a near-field focal point close to the surface of the first metal layer by means of the spatial phase gradient distribution formed by S-shaped metal patches with different in-plane rotation angles in the first metal layer.

[0014] Furthermore, the operating frequency band of the converging metasurface covers 10.5 GHz to 23 GHz, and within the operating frequency band, the convergence gain at the near-field focal point is 15 dB to 30 dB.

[0015] Furthermore, the application method also includes: coupling and extracting the converged satellite signal from the near-field focal point and feeding it into an indoor satellite receiving terminal.

[0016] The beneficial effects of the convergence metasurface on architectural window glass and its application method for satellite communication provided in this application are as follows: Compared with the prior art, in this application, the second metal layer acts as a continuous reflective substrate, completely reflecting the incident outdoor satellite microwave signal back to the direction of the first metal layer, avoiding energy loss caused by signal penetration through the glass, and achieving efficient interception and reuse of space microwave signals; the S-shaped metal patches arranged in a two-dimensional periodic array in the first metal layer, using their axisymmetric configuration and geometric phase control mechanism, reverse the polarization of electromagnetic waves during reflection (such as converting left-hand circular polarization to right-hand circular polarization), and introduce corresponding geometric phase shifts through the independent in-plane rotation angle of each unit; based on the spatial gradient distribution of the rotation angle of each unit, the reflected wavefront is precisely controlled, so that the originally diffused spatial electromagnetic energy is concentrated in a high-intensity near-field focal point close to the surface of the first metal layer in a passive state. The above design can transform a large area of ​​architectural window glass into a high-efficiency satellite signal collector without the need for an external power supply, providing a feasible technical solution to the engineering problem that outdoor satellite signals are difficult to penetrate modern architectural glass to enter the interior. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art 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.

[0018] Figure 1 A schematic diagram of a single structure of a converging metasurface on a building window pane used for satellite communication, provided in an embodiment of this application; Figure 2A schematic diagram of a single structure of the first metal layer in a converging metasurface on a building window pane used for satellite communication, provided in an embodiment of this application; Figure 3 A schematic diagram of an integral array of converging metasurfaces on a building window pane used for satellite communication, provided in an embodiment of this application; Figure 4 Simulation results of the amplitude of a single structure of a converging metasurface on a building window pane used for satellite communication, provided in an embodiment of this application; Figure 5 A simulation result diagram of the phase of a single structure of a converging metasurface on a building window pane used for satellite communication, provided in an embodiment of this application; Figure 6 Simulation focusing results of an integral array of converging metasurfaces on building window panes for satellite communication provided in this application embodiment. Figure 1 ; Figure 7 Simulation focusing results of an integral array of converging metasurfaces on building window panes for satellite communication provided in this application embodiment. Figure 2 .

[0019] The following are the labeling elements in the figure: 100 - Dielectric substrate; 210 - S-type metal patch; 211 - Metal strip; 212 - Metal connecting rod; 300 - Second metal layer. Detailed Implementation

[0020] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0021] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0022] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0023] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0024] Please refer to the following: Figure 1 and Figure 2 The present application provides a description of a converging metasurface for satellite communication on a building window pane. This converging metasurface includes a dielectric substrate 100, a first metal layer, and a second metal layer 300. The first metal layer includes a plurality of phase modulation structures arranged in a two-dimensional periodic array, each a symmetrical S-shaped metal patch 210. The second metal layer 300 serves as a continuous reflection substrate, reflecting incident satellite microwave signals back to the first metal layer to cooperate with the phase modulation structures in achieving polarization reversal and geometric phase modulation, ultimately passively converging the signal to a near-field focal point.

[0025] The converging metasurface on a building window pane for satellite communication provided in this application embodiment, compared with the prior art, uses a second metal layer 300 as a continuous reflective substrate to completely reflect the incident outdoor satellite microwave signal back to the direction of the first metal layer, avoiding energy loss caused by signal penetration through the glass, and achieving efficient interception and reuse of space microwave signals. The S-shaped metal patches 210 arranged in a two-dimensional periodic array in the first metal layer utilize their axisymmetric configuration and geometric phase control mechanism to reverse the polarization of electromagnetic waves during reflection (e.g., converting left-hand circular polarization to right-hand circular polarization), and introduce corresponding geometric phase shifts through the independent in-plane rotation angle of each unit. Based on the spatial gradient distribution of the rotation angle of each unit, the reflected wavefront is precisely controlled, allowing the originally dispersed spatial electromagnetic energy to converge at a high intensity near-field focal point close to the surface of the first metal layer in a passive state. This design, without the need for an external power supply, can transform a large area of ​​building window glass into a highly efficient satellite signal collector, providing a feasible technical solution to the engineering problem of outdoor satellite signals being difficult to penetrate modern building glass to enter the interior.

[0026] In one embodiment of this application, please refer to Figure 3 The S-shaped metal patch 210 located at different array positions has different in-plane rotation angles; a planar rectangular coordinate system is established with the center of the metasurface array as the origin, and the in-plane rotation angle of the S-shaped metal patch 210 has a specific spatial gradient distribution with its coordinate position; the spatial gradient distribution is used to reflect and converge the incident circularly polarized satellite microwave signal with a specific rotation direction to the near-field focal point close to the surface of the first metal layer.

[0027] In this embodiment, through the spatial gradient distribution design of the in-plane rotation angle described above, the converging metasurface achieves precise control of the phase of the reflected electromagnetic wavefront. Specifically, the S-shaped metal patches 210 at different array positions are assigned specific rotation angles according to their coordinates, so that the electromagnetic waves reflected by each unit form a converging wavefront that is in phase and superimposed in space. When a satellite microwave signal with a specific rotation direction (such as left-hand circular polarization) is incident perpendicularly, after being reflected by the second metal layer 300 and passing through the S-shaped metal patch 210 again, the signal rotation direction is reversed (converted to right-hand circular polarization). At the same time, the geometric phase shift introduced by each unit matches its spatial position, jointly driving the reflected wavefront to converge toward the preset near-field focus. This design does not require additional lenses or reflective surface structures; it can achieve near-field converging function solely through a planar metasurface, effectively simplifying the system structure and reducing processing difficulty and manufacturing costs.

[0028] In one embodiment of this application, each phase control structure independently constructs a local three-dimensional rectangular coordinate system: with the center of the local area of ​​the dielectric substrate 100 where the phase control structure is located as the origin, and the thickness direction of the dielectric substrate 100 as the Z-axis, the first metal layer and the second metal layer 300 are both parallel to the XY plane; with a symmetry axis of the S-shaped metal patch 210 as the rotation reference, the symmetry axis is deflected by an angle θ relative to the X-axis of the local three-dimensional rectangular coordinate system; when a circularly polarized electromagnetic wave of a specific rotation direction is incident perpendicularly and reflected by the second metal layer 300, the phase control structure introduces a geometric phase shift of 2θ for the reflected electromagnetic wave through the rotation angle θ of its S-shaped metal patch 210, thereby realizing independent control of the unit-level phase.

[0029] In this embodiment, by independently constructing a local three-dimensional Cartesian coordinate system for each phase control structure and introducing a 2θ geometric phase offset using the rotation angle θ of the S-shaped metal patch 210, high-precision independent control of the reflected electromagnetic wave phase is achieved. The phase control depends only on the in-plane rotation angle θ of the S-shaped metal patch 210, and is decoupled from the specific size parameters of the patch, avoiding the crosstalk problem of drastic amplitude fluctuations accompanying phase changes in traditional size scaling control methods, and ensuring a stable reflection amplitude over a wide frequency band. By continuously varying the rotation angle θ within the range of 0 to π, full-coverage control of the reflected wavefront phase from 0 to 2π can be achieved. The control accuracy depends only on the alignment accuracy of the laser etching process, which is convenient for manufacturing. The phase of each unit can be set independently as needed without interference, providing flexible design freedom for constructing arbitrary spatial phase gradient distributions (such as convergence, deflection, vortex beams, etc.).

[0030] Specifically, taking the center of the dielectric substrate 100 (a single unit consisting of an S-shaped metal patch 210 and the corresponding region of the dielectric substrate 100 and the second metal layer 300) as the origin, a local three-dimensional Cartesian coordinate system (x, y, z) is established along the thickness direction of the dielectric substrate 100, with the z-axis as the origin. A left-handed circularly polarized wave (LHCP) is incident perpendicularly to the first metal layer along the +z direction. The incident wave is reflected through the glass substrate in the second metal layer 300, and then re-coupled by surface plasmon resonance of the S-shaped metal patch 210 to radiate a right-handed circularly polarized wave (RHCP), achieving polarization reversal.

[0031] The angle between the symmetry center axis of the S-shaped metal patch 210 and the x-axis of the local three-dimensional rectangular coordinate system is set as the in-plane physical rotation angle θ. Compared to the reference element with θ=0, the element rotated by an angle θ produces a precise Δ for its radiated right-hand circularly polarized reflected wave. =2θ additional phase shift. By continuously varying θ within the range of 0 to π, broadband full-coverage independent control of the reflected wavefront phase from 0 to 2π can be achieved, and the control accuracy depends only on the etching accuracy, effectively avoiding the crosstalk problem of drastic amplitude fluctuations with phase changes in the traditional size scaling control method.

[0032] In one embodiment of this application, a global two-dimensional Cartesian coordinate system X is established on the plane containing the metasurface array. Y, located in the array at coordinates Rotation angle of the S-shaped metal patch 210 at the location It satisfies the following distribution pattern: ; Wherein, λ is the free space wavelength corresponding to the center frequency of the incident satellite microwave signal; The preset focusing distance; The initial constant phase is set to an arbitrary value; the focusing distance F is set to a near-field focal distance less than a set threshold, so that the reflected electromagnetic wave converges and converges close to the surface of the first metal layer.

[0033] In this embodiment, through precise mathematical mapping of the aforementioned rotation angle distribution law, the converging metasurface achieves near-field focusing and shaping of the front phase of reflected electromagnetic waves. This distribution law, based on geometric optics principles, ensures that reflected electromagnetic waves at various locations on the metasurface achieve in-phase superposition when propagating to the preset focal point, thereby forming high-intensity energy convergence in the near-field range. Simultaneously, by setting the focusing distance F to an extremely small near-field threshold, the reflected electromagnetic waves converge immediately upon contact with the surface of the first metal layer, breaking the physical limitations of the focal length in traditional parabolic antennas and efficiently compressing spatially dispersed electromagnetic energy into a localized area on the glass surface. Furthermore, the adjustable constant phase φ0 introduced in the distribution law allows for a constant shift in the overall phase distribution without changing the focusing position. This facilitates flexible adjustment of the absolute rotation angle assignment range of each unit in engineering design to adapt to the actual needs of different processing precision or material properties, significantly improving the design flexibility and engineering adaptability of the metasurface.

[0034] In one embodiment of this application, please refer to Figure 2 The S-shaped metal patch 210 includes two symmetrically arranged semi-circular metal strips 211 and an inclined metal connecting rod 212. The two symmetrically arranged semi-circular metal strips 211 together form an intermittent ring with two symmetrical openings. The two ends of the metal connecting rod 212 pass through the two openings respectively and are connected to the inner edges of the two metal strips 211 respectively. The metal strips 211 and the metal connecting rod 212 together form a centrally symmetrical S-shaped pattern.

[0035] In this embodiment, a pair of orthogonal electromagnetic resonant modes are excited within the target frequency band using a centrally symmetric structure, achieving efficient cross-polarization conversion of circularly polarized incident waves and providing a polarization basis for geometric phase modulation. Simultaneously, the symmetrical opening gap between the two semi-circular metal strips 211 and the metal connecting rod 212 together form a multi-resonance path equivalent circuit, maintaining a stable electromagnetic response within a wide frequency band of 10.5 GHz to 12.5 GHz, effectively broadening the metasurface's operating bandwidth and covering the mainstream Ku-band satellite communication frequency band. Furthermore, the characteristic radius, linewidth, and connecting rod tilt angle of the S-shaped patch can be independently adjusted, facilitating resonance characteristic optimization for different operating frequencies. This maximizes reflection amplitude and linearizes phase response within the target frequency band, significantly improving the metasurface's design flexibility and engineering adaptability.

[0036] In one embodiment of this application, the dielectric substrate 100 is a transparent glass plate.

[0037] In this embodiment, a transparent glass plate is used as the dielectric substrate 100, giving the converging metasurface both electromagnetic wave modulation and optical transparency. On one hand, the transparent glass plate has high transmittance in the visible light band, so its application to building exterior windows does not significantly affect indoor lighting, thus maintaining the original lighting function and visual transparency of the building windows. On the other hand, the transparent glass plate has stable dielectric properties in satellite communication frequency bands (such as 10.5 GHz to 12.5 GHz), serving as an effective medium for electromagnetic wave transmission and reflection, supporting electromagnetic coupling and phase modulation between the first metal layer and the second metal layer 300. This design allows the converging metasurface to be integrated with existing building glass curtain walls or exterior windows, directly converting ordinary building glass into a highly efficient passive receiver for satellite signals without altering the building's appearance or lighting conditions. This design demonstrates good engineering applicability and market potential.

[0038] Specifically, the transparent glass panel is made of borosilicate glass, which has a dielectric constant of 5.14 and a loss tangent of 0.008. These material parameters offer the following technical advantages in the 10.5 GHz to 12.5 GHz frequency band: First, the dielectric constant of 5.14 shortens the wavelength of electromagnetic waves in the glass substrate to approximately 0.44 times the wavelength in free space, facilitating phase accumulation and resonance modulation within a limited thickness, thereby reducing the overall profile height of the metasurface. Second, the low loss tangent of 0.008 indicates minimal energy attenuation during the round-trip propagation of electromagnetic waves through the glass substrate, effectively ensuring reflection efficiency and convergence gain. Third, borosilicate glass possesses excellent thermal shock resistance and chemical stability, enabling it to withstand long-term outdoor exposure to sunlight and rain, ensuring the long-term reliability of the metasurface in architectural window applications.

[0039] In one embodiment of this application, the materials of the first metal layer and the second metal layer 300 are both conductive thin films with a sheet resistance of less than 3Ω.

[0040] In this embodiment, a conductive film with a sheet resistance of less than 3Ω is used as the material for the first metal layer and the second metal layer 300, ensuring that the converging metasurface has excellent electromagnetic performance within the target operating frequency band. The low sheet resistance characteristic allows the conductive film to exhibit near-ideal conductor electrical behavior in the microwave band, effectively reducing ohmic losses and minimizing energy attenuation of the incident satellite microwave signal during reflection and resonance modulation, thereby achieving high reflection efficiency and converging gain. Simultaneously, the conductive film can be prepared using transparent conductive materials (such as silver film, indium tin oxide, etc.), achieving a certain degree of optical transparency while meeting the low sheet resistance requirement, which is beneficial for maintaining the light-transmitting performance of architectural glass. Furthermore, the conductive film is thin, lightweight, and flexible, making it easy to fabricate on glass substrates on a large area at low cost using mature processes such as magnetron sputtering and laser etching, exhibiting good processing adaptability and mass production potential.

[0041] In one embodiment of this application, please refer to Figure 2 The dielectric substrate 100 has a two-dimensional periodic parameter p = 5 mm and a thickness hg = 1.3 mm; the second metal layer 300 is a seamless metal layer with a thickness h2 = 0.0003 mm, used to achieve complete reflection of electromagnetic waves from 10.5 GHz to 12.5 GHz; the first metal layer has a thickness th = 0.0003 mm, and an S-shaped metal patch 210 is formed on it by laser etching process; the S-shaped metal patch 210 is characterized by: a radius b = 1.65 mm for the metal strip 211, a linewidth d = 0.66 mm for the metal strip 211, and an overall strictly centrally symmetrical configuration, which can excite stable electromagnetic orthogonal resonant modes in the target frequency band.

[0042] This application also provides a method for applying a converging metasurface on a building window pane for satellite communication as described above, including attaching the converging metasurface to the surface of the building window; using a second metal layer 300 to reflect the incident outdoor satellite microwave signal; and using the spatial phase gradient distribution formed by S-shaped metal patches 210 with different in-plane rotation angles in the first metal layer to passively converge the satellite microwave signal to a near-field focal point close to the surface of the first metal layer.

[0043] In this embodiment, through the above-described application method, the converging metasurface achieves efficient acquisition and on-chip convergence of outdoor satellite microwave signals in a passive operating state without the need for an external power supply. The metasurface is directly attached to the surface of existing building windows, eliminating the need to modify the building structure or install additional outdoor antenna devices. This achieves conformal integration with the building's glass curtain wall, avoiding the problems of bulky and complex installation of traditional satellite receiving equipment. Utilizing the perfect reflection characteristics of the second metal layer 300, outdoor satellite signals that would otherwise be reflected or blocked by the building glass are effectively intercepted and retained within the metasurface structure, solving the engineering problem of high-frequency microwave signals being unable to penetrate modern building glass to enter the interior. Through the spatial phase gradient distribution of the S-shaped metal patch 210 in the first metal layer, the reflected electromagnetic waves form a high-intensity energy convergence at the near-field focal point close to the metasurface surface, concentrating the diffuse electromagnetic energy received by a large area of ​​glass into a single point, providing a high-energy-density electromagnetic source for subsequent signal extraction from the glass edge. The above application method is simple to operate, requires no power supply, and is suitable for indoor satellite signal coverage scenarios in various modern buildings (especially glass curtain wall buildings), possessing good engineering practicality and promotional value.

[0044] In one embodiment of this application, the converging metasurface operates in a frequency band covering 10.5 GHz to 23 GHz, and within the operating frequency band, the convergence gain at the near-field focal point is 15 dB to 30 dB.

[0045] In this embodiment, the converging metasurface achieves high-gain near-field energy convergence over a wide frequency band, covering the range of 10.5 GHz to 23 GHz, encompassing the Ku band (12-18 GHz) and part of the K band. It is compatible with the downlink frequency bands of current mainstream low-Earth orbit satellite communication systems (such as Starlink, OneWeb, etc.), exhibiting excellent multi-system adaptability and spectrum compatibility. The convergence gain of 15 dB to 30 dB means that the signal power density at the near-field focal point can be increased by tens to thousands of times compared to the incident wave, concentrating the weak satellite signal that was originally diffused across the entire surface of the building glass into a single point, effectively compensating for the insufficient energy of the satellite signal reaching the ground after atmospheric attenuation. The wide frequency band coverage means that the metasurface does not require customized design for specific satellite communication frequency bands; a single metasurface can simultaneously support signal reception for multiple frequency bands, reducing deployment costs and equipment redundancy between different communication systems, resulting in significant economic benefits and engineering practical value.

[0046] In one embodiment of this application, the application method further includes: coupling and extracting the converged satellite signal from the near-field focal point and feeding it into an indoor satellite receiving terminal.

[0047] In this embodiment, by setting a coupling extraction structure (such as a microstrip probe, slot coupling structure, or coaxial feed port) at the near-field focal point, the high-intensity converged satellite signal is efficiently extracted and fed into the indoor receiving terminal, thus completely realizing a closed-loop signal link from outdoor space signal capture to indoor terminal use. The high energy density at the near-field focal point significantly reduces the difficulty of signal extraction. Even with a simple coupling structure, high coupling efficiency and signal-to-noise ratio can be obtained, avoiding the problem of insufficient receiving sensitivity caused by severe energy attenuation after the signal penetrates the glass in traditional transmission antennas. By passively converging the satellite signal and feeding it indoors, there is no need to deploy additional active amplification equipment or frequency conversion modules outdoors, simplifying the system architecture, reducing installation and maintenance costs, and avoiding engineering problems such as power supply and lightning protection for outdoor active equipment. This application method makes the building glass itself a core component of the satellite signal receiving system. The indoor receiving terminal can be flexibly arranged at the indoor side position corresponding to the near-field focal point and connected through transmission lines such as coaxial cables or waveguides, facilitating direct compatibility and interfacing with existing indoor satellite receiving equipment (such as set-top boxes, satellite modems, etc.), and has good system integration and user convenience.

[0048] Please see Figure 4 , Figure 4 This presents amplitude simulation results for the broadband reflection response of a single-unit structure of a convergent metasurface. Under infinite periodic boundary conditions, this artificial unit achieves a broadband reflection response in the frequency band from 10.5 GHz to 12.5 GHz. Figure 4 As can be seen, the reflection amplitude is at a good level within this frequency band.

[0049] Please see Figure 5 , Figure 5 This presents phase simulation results of the broadband reflection response of a single-unit structure on a convergent metasurface. Under infinite periodic boundary conditions, from... Figure 5 As can be seen, the reflection phase characteristics are excellent within the 10.5 GHz to 12.5 GHz frequency band. Specifically, the reflection phase exhibits a near-linear monotonic variation trend with frequency, and the phase change range covers approximately 360°, indicating that the unit possesses complete phase control capability within the target frequency band. The phase curve is smooth, without drastic jumps or nonlinear distortions, which is attributed to the centrally symmetric configuration of the S-shaped metal patch 210 and the stable response of its excited pair of orthogonal electromagnetic resonant modes within the operating frequency band. These wideband, linearized phase response characteristics enable precise geometric phase control of this metasurface unit within the 10.5 GHz to 12.5 GHz range, providing a reliable unit phase basis for subsequent broadband convergence designs of large-aperture arrays.

[0050] This embodiment provides a converging metasurface on a building window pane for satellite communication, comprising several phase modulation structures arranged in a two-dimensional periodic array on a dielectric substrate 100.

[0051] In the specific engineering design of this embodiment, the physical macroscopic size of the entire metasurface array is set to 30 cm × 30 cm. Combined with the physical period p = 5 mm of a single unit, the on-chip convergent metasurface contains a total of 60 × 60 units on a two-dimensional plane, that is, a total of 3600 S-shaped metal patches 210.

[0052] A global two-dimensional Cartesian coordinate system X is established with the geometric center of the 30 cm × 30 cm array as the origin. Y. To achieve on-chip focusing when receiving satellite microwave signals, parallel electromagnetic waves emitted from a satellite at infinity are required to converge toward a preset focal point after contacting the entire glass surface.

[0053] The preset coordinates of the near-field convergence focus are set as ( , , ).in Approaching 0 means the focal point is located very close to the surface of the first metal layer adjacent to the glass. The global coordinates are ( , The ideal compensation phase required for the i-th sigmoid cell (i=1,2,...,3600) at position ) is:

[0054] Subsequently, according to θ( , )= The absolute mapping relationship of / 2 allows for independent and precise assignment and photolithographic arrangement of the in-plane physical rotation angle θ of the 3600 S-shaped metal patches 210 distributed on the entire glass surface.

[0055] Please see Figure 6 and Figure 7 The array was simulated and focused to obtain the simulation results of the converged metasurface array on the building window glass sheet used for satellite communication.

[0056] Through the synergistic effect of this 30 cm × 30 cm large-aperture array, the microwave energy from outdoor satellites over a large area is not only completely blocked from the outside by the second metal layer 300, but also forcibly converted into converging surface waves propagating laterally along the metasurface by the continuously changing phase gradient on the front side, and finally converged at a very small focal point at the pre-designed glass edge. This design perfectly solves the problem of collecting and capturing high-frequency electromagnetic energy on large-aperture transparent building materials, laying the core physical foundation for the development of a new generation of building-integrated satellite receiving terminals.

[0057] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A converging metasurface on a building window pane for satellite communication, characterized in that, include: Dielectric substrate; The first metal layer includes a plurality of phase modulation structures arranged in a two-dimensional periodic array, wherein the phase modulation structure is an axisymmetric S-shaped metal patch. The second metal layer, which serves as a continuous reflector substrate, is used to reflect the incident satellite microwave signal back to the first metal layer. This, in conjunction with the phase modulation structure, enables polarization reversal and geometric phase modulation, ultimately passively focusing the signal to the near-field focal point.

2. The converging metasurface on a building window pane for satellite communication as described in claim 1, characterized in that, The S-shaped metal patches located at different array positions have different in-plane rotation angles; a Cartesian coordinate system is established with the center of the converging metasurface array as the origin, and the in-plane rotation angle of the S-shaped metal patch is spatially gradient distributed with respect to its coordinate position; the spatial gradient distribution is used to reflect and converge the incident circularly polarized satellite microwave signal to the near-field focal point close to the surface of the first metal layer.

3. The metasurface on building window glass patch aggregator for satellite communications of claim 1, wherein, Each phase control structure independently constructs a local three-dimensional Cartesian coordinate system: with the center of the local region of the dielectric substrate where the phase control structure is located as the origin, and the thickness direction of the dielectric substrate as the Z-axis, the first metal layer and the second metal layer are both parallel to the XY plane; with one axis of symmetry of the S-shaped metal patch as the rotation reference, the axis of symmetry is deflected by an angle θ relative to the X-axis of the local three-dimensional Cartesian coordinate system; when a circularly polarized electromagnetic wave of rotation is incident perpendicularly and reflected by the second metal layer, the phase control structure introduces a geometric phase shift of 2θ for the reflected electromagnetic wave through the rotation angle θ of its S-shaped metal patch, thereby realizing independent phase control at the unit level.

4. The metasurface on building window glass pane convergence for satellite communications of claim 2 or 3, wherein, A global two-dimensional rectangular coordinate system X Y is established with a plane in which the whole array of the metasurface converges The rotation angle of the S-shaped metal patch located at the coordinate The following distribution rule is met: ； Wherein, λ is the free space wavelength corresponding to the center frequency of the incident satellite microwave signal; The preset focusing distance; The initial constant phase is arbitrary; the focusing distance F is set to a near-field focal distance less than a set threshold, so that the reflected electromagnetic waves converge and converge close to the surface of the first metal layer.

5. The metasurface on building window glass patch aggregator for satellite communications of claim 1, wherein, The S-shaped metal patch includes: Two symmetrically arranged semi-circular metal strips together form an intermittent ring with two symmetrical openings. A metal connecting rod is arranged at an angle; the two ends of the metal connecting rod pass through two openings and are respectively connected to the inner edges of the two metal strips; the metal strips and the metal connecting rod together form a centrally symmetrical S-shaped pattern.

6. The metasurface on building window glass patch aggregator for satellite communications of claim 1, wherein, The dielectric substrate is a transparent glass plate.

7. The converging metasurface on a building window pane for satellite communication as described in claim 1, characterized in that, The first metal layer and the second metal layer are both made of conductive thin films with a sheet resistance of less than 3Ω.

8. A method for applying a converging metasurface on a building window pane for satellite communication as described in any one of claims 1 to 7, characterized in that, include: Attaching convergent metasurfaces to the exterior window surfaces of buildings; The second metal layer is used to reflect the incident outdoor satellite microwave signal; The satellite microwave signal is passively focused to the near-field focal point close to the surface of the first metal layer by the spatial phase gradient distribution formed by S-shaped metal patches with different in-plane rotation angles in the first metal layer.

9. The method of use as defined in claim 8, wherein, The converging metasurface operates in a frequency band from 10.5 GHz to 23 GHz, and within this frequency band, the convergence gain at the near-field focal point is from 15 dB to 30 dB.

10. The use according to claim 8, wherein the compound is ###0005### or a pharmaceutically acceptable salt thereof. Also includes: The converged satellite signal is coupled and extracted from the near-field focal point and fed into the indoor satellite receiving terminal.

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