252 results about "Wave absorption" patented technology

The invention relates to a vanadium dioxide-based multiband dynamic adjustable terahertz metasurface, which comprises a cross-like layer, a first dielectric layer, a first thin film layer, a double-opening metal layer, a second dielectric layer and a second thin film layer which are sequentially arranged from top to bottom, the cross-like layer, the first thin film layer and the second thin film layer are made of vanadium dioxide; the double-opening metal layer is annular, and the annular surface of the double-opening metal layer is provided with a first opening part and a second opening part which penetrate through the annular surface. Vanadium dioxide serves as materials of the cross-like layer, the first thin film layer and the second thin film layer, phase change characteristics of vanadium dioxide at different temperatures are utilized, and the first opening part and the second opening part formed in the double-opening metal layer are combined, so that the metasurface can achieve the wave absorbing function and the frequency selection function at the same time. Moreover, the metasurface provided by the invention is simple in structure and easy to process, and the production cost can be effectively reduced.

The invention provides a coding metasurface with terahertz wave absorption and reflection functions and application, the coding metasurface comprises at least one coding unit arranged in an array, each coding unit comprises a top resonance layer, a dielectric layer and a metal reflection layer which are sequentially arranged from top to bottom, the top resonance layer comprises a graphene resonance layer and a vanadium dioxide phase change layer, and the dielectric layer comprises a dielectric layer and a metal reflection layer. The graphene resonance layer comprises square graphene, the vanadium dioxide phase change layer comprises a square vanadium dioxide outer ring and a vanadium dioxide strip embedded in the vanadium dioxide outer ring, the vanadium dioxide outer ring is located on the inner side of the graphene, and the square edge of the vanadium dioxide outer ring and the square edge of the graphene are arranged in parallel at an interval; wherein the vanadium dioxide strips are arranged at the diagonal positions of the vanadium dioxide outer ring and are arranged at intervals with the vanadium dioxide outer ring, the advantages of a wave-absorbing metasurface and a reflection coding metasurface are integrated, and the signal generation power of 6G communication is greatly optimized.

The invention belongs to the technical field of electromagnetic wave functional materials, and particularly relates to a nested split ring wave-absorbing metamaterial and a preparation method thereof. The wave-absorbing metamaterial sequentially comprises an FSS metal structure layer, a dielectric layer and a metal matrix layer from top to bottom in the thickness direction, the FSS metal structure layer is formed by distributing structure units in a periodic array mode, each structure unit is composed of a double-opening outer ring shaped like a Chinese character'hui 'and a double-opening inner ring, the double-opening outer ring is a split square, and the double-opening inner ring is a hollow square. The structural units are symmetrically arranged about the diagonal line of the dielectric layer. The FSS metal structure layer designed by the invention has anisotropy, so that the polarization direction of an incident wave can be rotated by 90 degrees in a reflection mode. By means of the design, the two functions of electromagnetic wave absorption and polarization conversion are achieved at the same time, and meanwhile the effect of multiband wave absorption is achieved. Within the frequency band of 4 GHz to 18 GHz, the maximum wave-absorbing strength of the nested wave-absorbing metamaterial is as high as-30 dB, and the effective wave-absorbing bandwidth can reach 7.5 GHz.

The invention belongs to the field of optical sensing technology and food component analysis, and discloses a tea polyphenol detection method and a tea polyphenol detection device based on an infrared evanescent wave absorption spectrum. Comprising the following steps that a conical infrared optical fiber sensor is provided, the conical infrared optical fiber sensor is obtained by drawing an optical fiber with the diameter of 150-1000 microns to obtain a conical infrared optical fiber, and then the end faces of the two ends of the conical infrared optical fiber sensor are polished till the end faces of the optical fiber are free of scratches, so that the two end faces of the optical fiber are flat, smooth and bright and form mirror faces; the conical infrared optical fiber sensor is packaged in the sample pool, the upper end of the sample pool is open, and a to-be-detected sample solution is injected and fully coats the optical fiber; an 850-4000 cm <-1 > infrared light source is provided, focused infrared light enters the optical fiber and is fully coupled with the optical fiber, an infrared evanescent wave absorption spectrum is collected, and qualitative and quantitative analysis is carried out on the tea polyphenol content based on the tea polyphenol characteristic peak intensity. The method for detecting the tea polyphenol has the characteristics of rapidness, high sensitivity and low detection limit.

The invention relates to the technical field of layered products, and particularly discloses a skin material for wave-absorbing hiding and a preparation method. The skin material is of a layered structure and comprises a bionic micro-forest wave-transparent layer, a gradient transition layer, a wave-absorbing layer with a'skeleton-matrix 'dual-network structure, a reflecting layer and a heat-insulating layer which are sequentially arranged from top to bottom. A micro-cone array is arranged on the surface of the bionic micro-forest wave-transparent layer, so that broadband impedance matching is realized; the wave-absorbing layer comprises a three-dimensional ceramic skeleton and a magnetic-dielectric composite matrix filled in pores of the skeleton, and magnetic absorbents in the wave-absorbing layer are directionally arranged in the layer plane direction through a magnetic field auxiliary technology. The skin material prepared by the invention has excellent comprehensive performance of ultra-wideband wave absorption, high mechanical strength, light weight and high temperature resistance, and is particularly suitable for stealth requirements in the field of aerospace.

The invention relates to the technical field of terahertz metamaterial devices, in particular to an ultra wide band / double narrow band switchable terahertz wave absorber based on vanadium dioxide and sensing application. The wave absorber is formed by periodically arranging and combining a plurality of metamaterial square structure units, and no gap exists between adjacent periodic units. Each metamaterial square structure unit is composed of six layers from top to bottom, namely a VO2 resonance layer, a photonic crystal plate dielectric layer, a VO2 thin film, a metal resonance layer, a polycrystalline silicon dielectric layer and a gold substrate. The reversible phase change process of vanadium dioxide from a metal state to an insulation state is realized through external excitation (light, temperature and voltage). When vanadium dioxide is in a metal state, the terahertz ultra-bandwidth absorption function is achieved, when vanadium dioxide is in an insulated state, the terahertz wave double-narrow-band absorption function is achieved, and conversion between the ultra-wide band and the double narrow bands of the wave absorber is achieved. According to the terahertz wave absorber, the ultra-wideband / dual-narrowband conversion function of terahertz wave absorption can be achieved on one device, the defects that an existing terahertz wave absorber is complex in structure and the absorption characteristic is fixed once the terahertz wave absorber is manufactured are overcome, and the sensing function application of a single narrowband in the terahertz wave absorber is researched.

Embodiments of the present disclosure disclose wave-absorbing materials, device for wave-absorbing and heat-dissipating including the same, and methods of preparing the same. The device for wave-absorbing and heat-dissipating comprises: a wave-absorbing layer, the wave-absorbing layer being prepared from raw materials comprising wave-absorbing material and heat-dissipating material, the wave-absorbing layer in which the wave-absorbing material and the heat-dissipating material are in a first mass ratio; a heat-dissipating layer, the heat-dissipating layer being adjacent to the wave-absorbing layer, the raw material for preparing the heat-dissipating layer comprising wave-absorbing material and heat-dissipating material; the mass ratio of the wave-absorbing material and the heat-dissipating material in the heat-dissipating layer is a second mass ratio; the first mass ratio is greater than the second mass ratio. The solution of the present disclosure is capable of reducing cost and occupying space while safeguarding the wave-absorbing performance and heat-dissipating performance of the device for wave-absorbing and heat-dissipating.

An electromagnetic-wave absorber and reflector includes a base material, and a plurality of unit patterns made of conductive material disposed at even intervals on a surface of the base material. In the electromagnetic-wave absorber and reflector, a portion of each of the plurality of unit patterns overlaps with a portion of adjacent one of the plurality of unit patterns in a stacking direction of the base material, and the portion of each of the plurality of unit patterns and the portion of adjacent one of the plurality of unit patterns have a dielectric layer interposed in between.

The invention belongs to the technical field of mine geophysical prospecting, and particularly relates to a cross-hole radar perspective data processing method and system for a coal mine driving face, and the method comprises the steps: firstly constructing a real inter-hole detection region according to a transmitting hole track and a receiving hole track; according to a preset observation system, radar rays are drawn in the inter-hole detection area, and the path value, the transmitting antenna direction factor and the receiving antenna direction factor of each radar ray are calculated; and finally, constructing a radar wave energy attenuation equation set based on the geometrical shape of the inter-hole detection area, the radar ray path, the transmitting antenna direction factor and the receiving antenna direction factor, and carrying out joint iterative solution on the radar wave energy attenuation equation set to obtain radar wave absorption coefficient distribution in the inter-hole detection area of the tunneling working face. According to the invention, the problem of poor detection precision caused by inaccurate radar wave absorption coefficient in the existing cross-hole radar tomography of the coal mine driving working face can be solved.

The invention belongs to the technical field of metamaterials, and particularly relates to an adjustable wave-absorbing and reflecting integrated metamaterial structure which comprises a plurality of basic units arranged in a periodic array mode, and each basic unit comprises a resonance unit, a dielectric layer and a reflecting plate which are sequentially arranged in a stacked mode. The dielectric layer can be deformed, so that a cavity is formed between the dielectric layer and the reflecting plate or the dielectric layer is tightly attached to the reflecting plate; each resonance unit comprises four arc-shaped sections which are sequentially connected with one another, the four arc-shaped sections are arranged in a central symmetry mode, sharp corner parts extending towards the center of the resonance unit are formed at the connecting positions of the tail ends of the adjacent arc-shaped sections, and a gap is formed between every two opposite sharp corner parts. According to the invention, the reconfigurability is good, the use flexibility and deformability are very high, the state can be conveniently adjusted according to the actual use requirement so as to switch the use mode, and the 4.9 GHz-16.3 GHz broadband wave absorption or complete reflection function can be realized.

The invention relates to the field of materials, and provides a layered Ti3C2Tx / MXene loaded FeCo nanoparticle composite material, a preparation method and application, FeCo nanoparticles prepared by a hydrothermal method and Ti3C2Tx / MXene prepared by an in-situ etching method are combined by adopting an electrostatic self-assembly method, so that the composite material with a layered structure is obtained, and the FeCo nanoparticles with soft magnetic properties are loaded between layers and on the surface of the Ti3C2Tx / MXene material. The FeCo nanoparticles can adjust the dielectric property of the composite material, so that the composite material can be widely applied to the field of wave absorption. The method has the beneficial effects of simple equipment, low production cost, high production efficiency, greenness and no pollution. The composite material is a high-reflection and low-absorption material in the frequency band of 170-220GHz, and the absorption rate is 10-30%. In the range of 0.2-3 THz, the product prepared by the method also has a wave-absorbing effect, and the absorption coefficient is 100-150 cm <-1 >.

The invention relates to the field of ocean renewable energy technology utilization, and provides an oscillating water column type wave energy power generation device based on a superstructure, which comprises an oscillating water column main body, a superstructure assembly, a top shell and a power generation unit, and is characterized in that the interior of the oscillating water column main body is provided with the superstructure assembly formed by a plurality of guide plates which are arranged along the radial direction and extend in a horn shape; the oscillating water column body is internally divided into a plurality of independent oscillating water column cavities with gradually-changed sizes by combining with the partition plate assembly, an air chamber is defined by the top shell and the oscillating water column body, and airflow energy generated by water column oscillation driving is converted into electric energy through the power generation unit. The power generation unit can adopt a plurality of split type air turbines to generate power or a general type air turbine to generate power. The special fluctuation performance of the superstructure is fully exerted, efficient broadband capture and wave absorption are achieved, meanwhile, wave loads are effectively reduced, diversified integration of wave energy power generation devices is developed, sea area resources and operation and maintenance cost are saved, and negative environmental influences are reduced.

The invention discloses a NiZnCu ferrite composite metasurface with a P wave band broadband and a low RCS (Radar Cross Section) based on 1-bit coding. Firstly, the impedance matching condition of the ferrite is improved through Mn < 2 + > ion doping, so that when the thickness of the NiZnCu ferrite is 2 mm, effective wave absorption with the reflection loss smaller than-10 dB is achieved within the range of 0.25 GHz to 1.0 GHz. Furthermore, NiZnCu ferrite is combined with a sandwich structure (square metal sheet / FR4 / metal back plate, 6 mm) to construct a 1-bit coding metasurface structure unit, optimal array arrangement is obtained by adopting a genetic algorithm, and directional reflection is reduced to the greatest extent. And finally, full-wave simulation software is used for verification, and the result shows that the NiZnCu ferrite composite coding metasurface can further reduce the RCS by using the diffuse reflection effect on the basis of keeping the ferrite wave absorbing effect, the range of the RCS is 0.50 GHz-0. 75 GHz, and the maximum RCS reduction value can reach 29.4 dB.

The invention discloses a multi-layer resistive film frequency selective surface composite wave-absorbing device with high bearing and wave-absorbing integrated functional characteristics. The composite wave absorbing device sequentially comprises a mechanical bearing layer composed of a wave-transparent dielectric plate subjected to impedance modification and a dielectric isolation layer from top to bottom. The wave-absorbing functional layer is formed by arranging three layers of resistive film frequency selective surfaces, three layers of dielectric isolation layers and six layers of wave-transparent dielectric plates at intervals; and the total reflection bottom plate is formed by a carbon fiber plate or a metal plate. According to the invention, a layer of resistive film frequency selective surface is embedded in the wave-transparent dielectric plate, so that the wave-absorbing bandwidth can be effectively expanded while the high-bearing mechanical property is ensured; a layer of wave-transparent dielectric plate is laid on the upper portion and the lower portion of the frequency selective surface of each resistive film in the wave-absorbing functional layer so as to further reinforce the mechanical bearing characteristic of the composite wave-absorbing device.

The invention discloses a transmission type multifunctional non-reciprocal unit structure metasurface which comprises a plurality of unit structures, the unit structures are arranged from left to right in the-z direction, each unit structure comprises metal layers and dielectric layers, the metal layers and the dielectric layers are alternately arranged at intervals, every two adjacent metal layers at intervals comprise orthogonally-prevented open square rings, and the open square rings are connected with the metal layers at intervals. Wherein the phase change material is embedded into one of the open square rings. According to the transmission type multifunctional non-reciprocal unit structure metasurface, non-reciprocal regulation and control of electromagnetic waves can be achieved through a simple structural design without an external magnetic field, the metasurface can perform different control effects on the electromagnetic waves which are incident in different directions and are in different polarization states, and the metasurface is high in practicability. The material has multiple functions of polarization conversion, wave absorption and the like, and the performance of the material can be dynamically regulated and controlled without depending on an external magnetic field.

The present invention provides a flexible sheet of broadband wave-absorbing metamaterial based on carbon-based materials. The sheet comprises a reflective layer and a dielectric layer embedded with periodically arranged structural units. The dielectric layer is arranged above the reflective layer. The preparation of the sheet comprises the following steps: the dielectric layer is arranged according to the size of the periodic resonant structural unit, and every other unit cell is arranged. P The size of the double-layer concentric cylindrical hole is mechanically punched; the small hole side of the medium plate with the hole is cleaned with anhydrous ethanol, and the reflective layer is applied; the graphene or carbon nanotubes are mixed with the adhesive to form a carbon composite for use; the graphene or carbon nanotubes are filled into the periodically arranged holes in step 1 with a scraper; the carbon composite is dried naturally until it is completely dry. The flexible sheet of this patent achieves a wide-band wave absorption effect in the range of 2 to 18 GHz, has a simple manufacturing process, is easy to use, can be applied to the object to be measured, and effectively reduces the characteristic signal of the radar wave of the target object.

The invention provides a reconfigurable metasurface capable of realizing absorption, transmission and reflection polarization conversion. The metasurface unit comprises four dielectric plates which are printed with polygonal phase change materials, polygonal phase change material rings, first phase change material strips, metal strips, a plurality of polarization conversion metal units and second phase change material strips, wherein the first phase change material strips and the metal strips are alternately arranged, the polarization conversion metal units are periodically arranged, and the second phase change material strips are spatially crossed with the first phase change material strips and the metal strips. When electromagnetic waves irradiate from the top, the first phase change material is in a metal state, the second phase change material is in a medium state or a metal state, and the metasurface shows the broadband wave-absorbing characteristic. When electromagnetic waves irradiate from the bottom and the two are both in a metal state, the metasurface realizes the linear polarization and circular polarization conversion characteristic of a reflection state. And if the first phase change material is in a medium state and the second phase change material is in a metal state, the metasurface realizes the linear polarization conversion characteristic of a transmission state. According to the design, the defect that the application range is narrow in the prior art is effectively overcome, the application scene is widened, and the wave absorbing bandwidth is enhanced.

The invention provides a tunable metamaterial wave absorber, which comprises a flexible dielectric layer, a metal reflecting layer and a plurality of periodically arranged metal resonant structures, the metal resonant structures are arranged on the first surface of the flexible dielectric layer, the metal reflecting layer is arranged on the second surface of the flexible dielectric layer, and the flexible dielectric layer deforms when being stressed, so that the shape of each metal resonant structure is changed, and the area of each metal resonant structure is not changed. The shape of each metal resonance structure is changed in real time, so that the electromagnetic resonance frequency of the metamaterial wave absorber can be adjusted, wave absorbing requirements of different frequencies are met, a plurality of frequency points with the absorption rate higher than 90% exist in the frequency band of 2-18 GHz, and the metamaterial wave absorber has wide application prospects in the fields of radar stealth, wearable equipment, intelligent radio frequency tags and the like.

The invention provides a wave-transparent band frequency-adjustable frequency selection surface, which comprises a loss layer, a frequency selection layer and a bias network, the loss layer and the frequency selection layer are periodically arranged, the loss layer comprises a first resonant structure and a second resonant structure, and the frequency selection layer comprises a third resonant structure. The upper bias network and the lower bias network are respectively connected with direct-current voltages with different polarities, so that the variable capacitance diodes in the first resonant structure and the third resonant structure work under different voltages to generate different capacitance values, the resonant frequency point of the loss layer and the resonant frequency point of the frequency selection layer in the structures generate frequency shift at the same time, and finally continuous adjustability in the wave-transparent frequency band of 5.51 GHz to 6.31 GHz is achieved. Under the action of the second resonant structure and other lumped resistors of the loss layer, wave absorption within the frequency band range of 4.31 GHz to 5.15 GHz and the frequency band range of 6.31 GHz to 13.81 GHz is achieved. The device has the characteristics of continuous frequency modulation and out-of-band wave absorption, can effectively suppress interference of outside electromagnetic waves in other frequency bands or electromagnetic waves in a frequency band close to a communication frequency band on communication, can reduce the radar cross section of a target, and is beneficial to target stealth.

A GaSb substrate, a GaSb buffer layer, an epitaxial thin film, a first electrode and a second electrode are adopted, the GaSb substrate, the GaSb buffer layer and the epitaxial thin film are sequentially stacked, and the epitaxial thin film comprises a first contact layer, a long wave absorption layer, a medium wave absorption layer and a second contact layer which are sequentially stacked; the first contact layer is in contact with the GaSb buffer layer; and etching is carried out on the basis of the epitaxial thin film to form a step, the depth of the step reaches the first contact layer, the first electrode is conducted with the first contact layer, the second electrode is conducted with the second contact layer, finally, a two-color infrared detector structure is formed, 12ML InAs / 2ML InAs0. 5Sb0. 5 superlattice is used as a material of the medium-wave absorption layer, good lattice matching is formed between the medium-wave absorption layer and the long-wave absorption layer, and the performance of the two-color infrared detector is improved. Therefore, interface defects and stress accumulation caused by lattice mismatch are reduced, and a smooth and uniform interface is provided for subsequent growth of the epitaxial layer, so that the growth difficulty of the epitaxial layer can be reduced.

To provide an electromagnetic wave absorber having a high electromagnetic wave absorption characteristic, and a wide absorption band width.SOLUTION: An electromagnetic wave absorber includes a structure that a first dielectric body and a second dielectric body are laminated, and in which a complex dielectric constant in a maximum absorption frequency of the first and second dielectric bodies satisfies the following formulas (1) and (2): 8≤ε1'-ε2'≤40...(1), and 5.5≤ε1"-ε2"≤25...(2) (In formula (1), ε1' is a real part of the complex dielectric constant of the first dielectric body, and ε2' is a real part of the complex dielectric constant of the second dielectric body. In formula (2), ε1" is an imaginary part of the complex dielectric constant of the first dielectric body, and ε2" is an imaginary part of the complex dielectric constant of the second dielectric body.)SELECTED DRAWING: None

The invention discloses a wave-absorbing and wave-transmitting switchable multifunctional stealth metasurface, and belongs to the technical field of electromagnetic functional materials, the metasurface is formed by periodically arranging a plurality of metasurface units, each metasurface unit comprises a resonance layer, a graphene capacitor layer and a frequency selection surface layer, a first resonance layer, a second resonance layer, a graphene capacitor layer, a third resonance layer and a frequency selective surface layer are sequentially arranged from top to bottom, and gaps between the layers are filled with PMI foam to serve as supports. The resonance layer and the frequency selection surface layer are formed by a dielectric substrate and a metal patch; a PIN diode is integrated on the metal patch of the frequency selection surface layer; and a rectangular groove is formed in the middle of the graphene capacitor layer. According to the multifunctional stealth metasurface, the scattering characteristic of the metasurface is tunable, the transmission characteristic of the metasurface is reconfigurable, and the multifunctional stealth metasurface has the advantages of being wide in scattering adjustment bandwidth, small in transmission frequency band loss, low in manufacturing cost, easy to adjust and control and the like.

The invention discloses a transparent ultra-wideband electromagnetic shielding wave-absorbing body for a wireless and visible light communication integrated system. The transparent ultra-wideband electromagnetic shielding wave-absorbing body is formed by arranging one or more metamaterial units, each metamaterial unit is formed by tightly attaching an upper ITO-PET-PDMS structure and a lower ITO-PET-PDMS structure; each ITO-PET-PDMS structure comprises a transparent substrate PDMS layer, a polyethylene glycol terephthalate (PET) layer and an ITO ceramic thin film layer from top to bottom, and the transparent substrate PDMS layer, the PET layer and the ITO ceramic thin film layer are sequentially arranged from top to bottom. The structure designed by the invention has the characteristics of broadband wave absorption, wide-angle wave absorption and optical transparency. The transparent ITO ceramic thin film is adopted to construct a multi-resonance topological structure, the wave absorption rate of the transparent ITO ceramic thin film exceeds 90% at 4.2-16.3 GHz (the relative bandwidth is 118.0%), the wave absorption rate of the transparent ITO ceramic thin film exceeds 75% within the incidence angle of 60 degrees, and the transparent ITO ceramic thin film can be applied to electromagnetic energy absorption covering a plurality of wireless communication frequency bands such as GPS and WiMAX. The structure designed by the invention has high optical transmittance.

The invention discloses a vegetation model and plastic blind ditch combined composite wave absorbing device which comprises a square supporting amplitude modulation frame, a lifting mechanism and a vegetation model. The square supporting amplitude modulation frame comprises a bottom support, a block-shaped plastic blind ditch plate arranged on the bottom support, two guide sliding rails arranged on the two sides of the top of the block-shaped plastic blind ditch plate correspondingly, and a porous net-shaped vegetation fixing grid arranged between the two guide sliding rails. A plurality of plug-in type grooves are formed in the porous net-shaped vegetation fixing grids, vegetation strips are inserted into the plug-in type grooves to form a vegetation model, one end of the bottom support is connected with the water tank, the other end of the bottom support is connected with the lifting mechanism, and the lifting mechanism is used for adjusting the angle between the square supporting amplitude modulation frame and the water tank. The vegetation model and the plastic blind ditch plate are combined, reflection waves are reduced through double wave absorption of the vegetation model and the plastic blind ditch plate, and the wave absorption effect is improved.

This invention provides a two-dimensional wave-generating water tank with active wave absorption function driven by a voice coil motor, comprising a wave-generating device, a water tank body, and a force feedback active wave-absorbing device. The force feedback active wave-absorbing device and the wave-generating device are rigidly connected to both sides of the water tank body via brackets. Each includes a voice coil linear motor, a small processor, a magnetic grating displacement sensor, a lever amplification mechanism, and a float. The output end of the voice coil linear motor is connected to the lever amplification mechanism, which is connected to the float. The small processor is connected to the magnetic grating displacement sensor signal. The voice coil linear motor is used to apply a wave-absorbing force f to the float based on the data from the magnetic grating displacement sensor. a (t). This invention is applicable to small and medium-sized wave pools, occupies little space, and has high precision, greatly enriching the application scenarios of wave pools. It is convenient for transportation, installation, debugging, and mobile use in different scenarios, providing a foundation for subsequent classroom demonstrations, student experiments, and equipment sharing.

The invention discloses a broadband low-scattering reflection surface based on a back-loaded active microstrip network, which integrates an antenna unit with the back-loaded active microstrip network to control the response of the low-scattering reflection surface to incoming waves. Wherein the antenna unit sequentially comprises a top dielectric matching layer, a dipole patch, a first dielectric substrate, a coupling capacitor metal disc, a second dielectric substrate, a metal floor and a third dielectric substrate from top to bottom; the back-loaded active microstrip network is arranged below the third dielectric substrate; after receiving an incident wave, the antenna unit transmits the incident wave into the back-loaded active microstrip network, and after network processing, the incident wave is radiated to a free space through the antenna unit; the back-loaded active microstrip network realizes phase control of TE polarized reflected waves by adjusting the on-off state of the PIN tube, and realizes absorption of TM polarized incoming waves by loading a resistor in the middle of the short-circuit microstrip line. According to the invention, low profile and miniaturization are ensured, and wave absorbing and active scattering regulation and control functions are realized at the same time.

The invention provides a wave absorbing unit and a wave absorbing structure, and relates to the technical field of electromagnetic wave absorbing materials. The wave absorbing unit comprises a first wave absorbing body and a second wave absorbing body. The first wave absorber is made of a dielectric material. The first wave absorbing body comprises a base and a wave absorbing main body, and the wave absorbing main body is conical or wedge-shaped; the wave absorbing body is arranged on the base, and a cavity is formed in the wave absorbing body. And the second wave absorbing body is made of a magnetic material. The second wave absorbing body is arranged on the side, away from the wave absorbing body, of the base, or the second wave absorbing body is arranged in the cavity. The wave absorbing structure provided by the invention adopts the wave absorbing unit. According to the wave-absorbing unit and the wave-absorbing structure provided by the invention, the problems of large overall weight, high cost and high installation difficulty of a wave-absorbing material caused by increase of manufacturing materials in order to improve the wave-absorbing performance in the prior art can be solved.

The present invention discloses a wave-absorbing metamaterial, comprising: a plurality of metamaterial units arranged periodically, wherein each of the metamaterial units includes: a first loop disposed in a first plane; and a second loop disposed in a second plane, the first plane being perpendicular to the second plane so that the first loop is orthogonal to the second loop. The above technical solution of the present invention can achieve wave absorption within a large angular range while ensuring broadband wave absorption.

This invention discloses an adaptive wave-absorbing experimental device and method under a hypergravity field. The device includes: a model box with a top plate and a wave-absorbing mounting base plate installed on the underside of the top plate; a distance adjustment module including a first ball screw, a linear motion mechanism, and a first grid plate, wherein the linear motion mechanism is mounted on the wave-absorbing mounting base plate, and the first ball screw is used to move the first grid plate in the wave propagation direction through the linear motion mechanism to adjust the distance between the first grid plate and the side wall of the model box; an aperture ratio adjustment module including a second ball screw and a second grid plate, wherein the second ball screw is mounted on the first grid plate and is used to control the movement of the second grid plate perpendicular to the wave propagation direction to adjust the aperture ratio of the grid plate formed by the second grid plate and the first grid plate; and a control system for acquiring the wave height of the reflected wave and controlling the operation of the distance adjustment module and the aperture ratio adjustment module according to the wave height.

The application discloses a broadband low radar scattering cross section antenna loaded with an ATFSS, which comprises three layers of dielectric plates, namely, an upper layer plate, a middle layer plate and a lower layer plate, the upper surface and the lower surface of the upper layer plate are attached with wave absorbing structures, the lower surface of the middle layer plate is attached with a band-pass FSS structure, the upper surface of the lower layer plate is attached with a patch antenna, the lower surface of the lower layer plate is a metal ground plate, coaxial line feeding is adopted, and the upper layer plate, the middle layer plate and the lower layer plate are all air cavities. The broadband low radar scattering cross section antenna adopts the wave absorbing structure with a multi-resonance structure and the band-pass FSS structure, can realize the integrated characteristics of wave absorption and wave transmission, and the wave absorbing structure and the band-pass FSS can be loaded as a coating above the microstrip patch antenna to realize the RCS reduction in a wide frequency band under the condition of ensuring the normal radiation of the antenna.