15 results about "Electromagnetic metasurface" patented technology

This invention discloses a reconfigurable electromagnetic metasurface unit integrating transmission, reflection, and absorption functions. The metasurface unit includes two identical polarized resonant patches connected by a central metal via. Four positive intrinsic negative PIN diodes are integrated into the tunable patch layer, and the state of the four PIN diodes is dynamically controlled by a DC bias voltage. This invention can flexibly switch the operating mode of the metasurface by a DC bias voltage, and control the electromagnetic wavefront in real time in absorption mode (low RCS), transmission mode, and reflection mode. Through array coding, it can realize functions such as high-gain beamforming, beam scanning, beam focusing, RCS reduction, beamforming, and vortex beam generation. It has the advantages of simple design, low cost, and excellent performance, and has great potential in fields such as smart skin, electronic countermeasures, and wireless communication systems.

We utilize high-quality-factor (high-Q) metasurfaces patterned either in or adjacent to electro-optical or thermo-optical materials such as lithium niobate, barium titanate, or thermally-sensitive polymers. The metasurface includes nanoantennas that act as dipole emitters; the particular structure and arrangement of nanoantennas can steer light to particular directions or focus light, The electromagnetic metasurface supports one or more guided mode resonances. The metasurface also includes a perturbation superposed on the metasurface features and configured to couple free-space radiation to the guided mode resonances.

The application discloses a low-scattering large-angle wave-transparent electromagnetic metasurface based on angle multiplexing, which comprises an angle selection layer and a phase control layer; the phase control layer is used for controlling the reflection phase of an angle incident electromagnetic wave in a first range; the angle selection layer is used for selectively transmitting an angle incident electromagnetic wave in a second range and selectively reflecting an angle incident electromagnetic wave in the first range, and comprises a second dielectric substrate and metal grounds on the upper and lower surfaces of the second dielectric substrate, the upper metal ground is etched with first and second slot structures, and the lower metal ground is etched with third and fourth slot structures; the two layers of slot structures are arranged in a staggered mode in a unit arrangement direction of a plane, and the first, second, third and fourth slot structures extend to the edges of the unit structures along another unit arrangement direction of the plane and are in communication with the slot structures of adjacent units. The application realizes the integration of scattering suppression and large-angle wave-transparent functions, and effectively improves the function multiplexing capability and system integration degree of the electromagnetic metasurface device.

This invention discloses an intelligent protection method and system for low-voltage switchgear in power plants based on multi-dimensional safety monitoring, relating to the field of electrical equipment condition monitoring. The method includes: real-time acquisition of multi-physics field data inside the low-voltage switchgear using an electromagnetic metasurface array; extraction of spatiotemporal features characterizing the switchgear's operating state; inputting these spatiotemporal features into a pre-constructed digital twin model of the field for state determination and abnormal pattern identification, and generating a corresponding field reconstruction strategy. This field reconstruction strategy defines the target electromagnetic parameters and spatial interaction modes of the electromagnetic metasurface array; and, according to the field reconstruction strategy, sending control commands to the electromagnetic metasurface array to reconstruct the local electromagnetic field environment of the corresponding area inside the low-voltage switchgear. This application solves the technical problems of insufficient monitoring accuracy and passive, lagging protection methods in existing low-voltage switchgear protection systems for power plants, achieving improved monitoring accuracy and enabling proactive intervention and precise protection against fault precursors.

The application discloses a kind of electromagnetic super surface unit structure optimization method based on constraint space mapping, belong to electromagnetic super material design technical field.The application is to solve the problem of low optimization efficiency and difficult to handle constraint condition in the process of super surface unit structure optimization in prior art, mainly using mapping multidimensional structure variable to the convex constraint space formed by inequality constraint condition, and combining multi-objective optimization algorithm for efficient optimization.By using direction vector, scale factor to represent structure variable vector, the initial solution generation process that satisfies complex constraints is simplified, and the global search ability and convergence speed in the constraint space are improved.The method can quickly converge to local optimal solution under complex constraint conditions, and effectively find the Pareto optimal solution, thereby providing an efficient and accurate solution for multi-objective optimization of electromagnetic super surface unit structure.

The application relates to the technical field of film switches and discloses an anti-interference intelligent household appliance wireless communication film switch device, which comprises, from bottom to top, a substrate layer, a signal control circuit layer, a ground electrode shielding layer, a reconfigurable electromagnetic super surface layer and a haptic panel layer; the reconfigurable electromagnetic super surface layer is composed of array-arranged electromagnetic super surface units, the reflection phase and polarization characteristics of electromagnetic waves of the corresponding super surface units are dynamically regulated by changing the impedance value of the adjustable impedance element; the haptic panel layer is integrated with a distributed haptic sensing array; the device further comprises a radio frequency sensing module and an edge computing processing unit. Through dynamic impedance adjustment of the adjustable impedance element of the super surface unit, the reflection phase and polarization characteristics of electromagnetic waves can be regulated, real-time reactance compensation is realized in cooperation with a haptic electromagnetic coupling prediction model, selective regulation is carried out on interference signals of different frequency bands and different directions, and precise interference signal suppression is realized while ensuring the permeability of the communication frequency band.

The invention provides a broadband phase-adjustable electromagnetic metasurface, a preparation method and a phase adjustment and control method, relates to the technical field of microstructures, and aims to solve the technical problem that the phase adjustment and control frequency band range of the electromagnetic metasurface is narrow. The broadband phase-adjustable electromagnetic metasurface is formed by module structures arranged in an array mode, and each module structure comprises a flexible dielectric layer, a driving control circuit and a sealing cover plate. The flexible dielectric layer comprises micro-channel structures which are formed on the upper surface and are arranged in an array at intervals and driving ports formed in the lower surface, and the driving ports are connected with fluids in the micro-channel structures through driving channels; the driving control circuit is located below the flexible dielectric layer, is connected with the driving port through a flexible microtube, and is used for controlling the flowing length of the liquid metal in the flow channel structure; and the sealing cover plate covers the upper surface of the flexible dielectric layer, and the sealing cover plate is an elastic sealing cover plate. The frequency response capability of the electromagnetic metasurface can be adjusted in a range of 3.5 GHz to 12 GHz.

This invention discloses a multi-spectral intelligent control device based on programmable patterned electrodeposition, comprising at least two types of reversible metal electrodeposition units with different patterns, arranged in a pixelated array. Each reversible metal electrodeposition unit consists of an infrared high-transmittance substrate layer, a conductive thin film layer, a patterned dielectric layer, a metal ion electrolyte layer, and a counter electrode. The patterned dielectric layer has patterned grooves; when an electric field is applied, metal is deposited on the patterned grooves, thus presenting the corresponding pattern. This invention arranges the reversible metal electrodeposition units in a specific order to form a large-area pixelated array device. Each reversible metal electrodeposition unit is equivalent to a unit of an electromagnetic metasurface and can be independently controlled, realizing spatial programming and dynamic reconstruction of the target multi-spectral characteristics. This allows for real-time, dynamic, and reversible reconstruction of large-area macroscopic optical patterns, thermal radiation distributions, and microwave scattering fields.

An antenna element includes a first thin-film membrane, second thin-film membrane essentially parallel to and spaced apart from the first thin-film membrane, an electromagnetic metasurface on a first side of the first thin-film membrane opposite of the second thin-film membrane, and a metallic coating on a first side of the second thin-film membrane opposite of the first thin-film membrane. An antenna array is also disclosed.

The application discloses a flexible wide-band ultrathin radar and infrared compatible stealth metasurface and a preparation method, and belongs to the field of electromagnetic metasurfaces and micro-electro-mechanical systems. The metasurface is sequentially provided with an ultrathin multi-resonant spectrum selection layer, an anti-reflection impedance matching layer, a resonant loss layer, a magnetic medium attenuation layer and a coherent enhancement total reflection layer along the direction of electromagnetic wave incidence. The multi-resonant spectrum selection layer is designed with a geometric scale gradient change wave-absorbing pattern, the resonant loss layer is designed with a four-fold rotating arrow and a circular ring combined pattern, and the magnetic loss layer and the dielectric loss layer with low to high dielectric constants are combined to achieve a synergistic absorption mechanism, so that the radar-infrared compatible stealth effect of an ultrawide working frequency band is finally realized. The metasurface structure has high-efficiency wide-band absorption performance and excellent mechanical flexibility, the preparation process is simple and reliable, large-area, low-cost and repeatable manufacturing can be realized, and the metasurface structure has a wide application prospect in the fields of multi-band stealth and flexible electromagnetic devices.

The application provides an adaptive reconfigurable intelligent radar radome system, which can realize adaptive bidirectional band-pass high transmission for any radar signal when the radar works, and realize full-band shielding when the radar does not work, so that electromagnetic protection and electromagnetic stealth of the radar are maximized. According to the principle of generalized Fresnel law, by increasing active feeding on the electromagnetic super surface, the surface current density of the electromagnetic structure can be adaptively changed according to the passing radar signal, so that the band-pass characteristic without transition frequency band at any frequency point and any bandwidth can be realized. The application solves the problems that the traditional frequency selective surface cannot realize full-band shielding when the radar does not work, and cannot adaptively realize the band-pass of the same frequency as the radar signal when the radar works, and can be applied in the field of intelligent stealth of the radar radome.

A pressure sensor based on electromagnetic metasurface and a preparation method and assembly thereof, the pressure sensor based on electromagnetic metasurface comprises: a plurality of periodically arranged metasurface structure units, the period size of the metasurface structure unit is less than half the wavelength of the pressure sensor at the working frequency; the metasurface structure unit comprises: a flexible substrate with opposite first and second surfaces; a metal back plate located on the first surface of the flexible substrate, the surface opposite to the flexible substrate in the metal back plate is used for receiving the measured pressure; a dielectric plate layer located on the second surface of the flexible substrate; a metal resonant unit located on the surface of the dielectric plate layer away from the flexible substrate; a protective layer located on the surface of the metal resonant unit, and the metal resonant unit is located between the dielectric plate layer and the protective layer. The present application binds the resonant frequency and the pressure, realizes the miniaturization and high endurance of the pressure sensor.

This invention discloses a multimodal brain tumor image segmentation method based on a metasurface encoder, relating to the fields of image processing and neural networks. The method includes: acquiring multimodal magnetic resonance imaging data and preprocessing it using an electromagnetic metasurface encoder to obtain preprocessed data; reducing the dimensionality of the original multimodal brain imaging data through rapid dimensionality reduction to decrease data processing time; inputting the preprocessed data into a deep learning network for image segmentation to obtain image segmentation results; the UNet semantic segmentation model used has been trained to identify and locate brain tumors; and reconstructing a high-resolution image based on the image segmentation results output by the deep learning network using a decoder. Compared with traditional brain tumor image segmentation methods, this invention significantly improves processing speed; due to the effective reduction of data dimensionality, the required storage space and computing resources are greatly reduced, providing a more economical and efficient solution for clinical applications and research.

The application discloses a curved surface conformal transparent wave absorber based on a parameterized crease design and a preparation method, belongs to the technical field of microwave absorbing materials and electromagnetic metasurfaces, and aims at solving the problems that the existing planar paper wave absorber cannot be attached to a complex curved surface and the traditional water bomb paper is prone to self-intersection on the curved surface. The wave absorber is a space three-dimensional metasurface folded by a single-layer film, is composed of a plurality of non-uniform periodic units connected in sequence along the y direction, each periodic unit comprises a seven-crease paper part A and an electromagnetic dissipation connecting part B, and the A and the B are alternately arranged along the y direction. A control point sequence is obtained by discretizing a target curved surface, the interval between adjacent control points and a local corner are calculated, the seventh crease length of each periodic unit and the y direction periodic arrangement size are determined according to an analytical relationship, the V-shaped groove opening of the seven-crease paper part A is upwardly formed into a main resonant cavity, the V-shaped groove opening of the electromagnetic dissipation connecting part B is downwardly formed into an auxiliary resonant cavity, and the two form a multi-stage electromagnetic dissipation structure.