42results about How to "Broaden the absorbing bandwidth" patented technology

The invention discloses an electromagnetic wave absorbing material with a periodic structure. The electromagnetic wave absorbing material comprises dielectric blocks formed by a magnetic wave absorbing material grid and a dielectric material, wherein the meshes on the magnetic wave absorbing material grid are through holes, and the dielectric blocks are embedded in the through holes of the magnetic wave absorbing material grid according to a certain periodicity. The preparation method of the electromagnetic wave absorbing material comprises the following steps of: selecting a magnetic wave absorbing raw material, and forming periodically arranged embedding holes on the magnetic wave absorbing raw material to obtain the magnetic wave absorbing material grid; then, selecting a dielectric material of which the relative dielectric constant is in a preset range, cutting the dielectric material into the dielectric blocks corresponding to the embedding holes in shape and size; embedding the prepared dielectric blocks in the embedding holes formed on the magnetic wave absorbing material grid one by one, and connecting together by an adhesive to get the electromagnetic wave absorbing material. The preparation method can effectively expand the operation bandwidth of the wave absorbing material without increase of the thickness, and simultaneously, can obviously reduce the volume density of the magnetic wave absorbing material.

The invention discloses a broadband wave-absorbing material based on sub-wavelength metal structures, and belongs to the field of microwave absorbing materials. The broadband wave-absorbing material is divided into three layers from top to bottom, namely a first dielectric substrate, a traditional wave-absorbing material substrate and a second dielectric substrate, wherein the first dielectric substrate is covered with rectangular metal structures which are periodically arrayed; the second dielectric substrate is covered with periodically-arrayed metal structures shaped like a Chinese character 'Hui'. On the basis of a traditional wave-absorbing material, the periodic sub-wavelength metal structures are introduced; the electromagnetic wave loss effect of the traditional wave-absorbing material is improved according to the local electromagnetic wave control characteristics of the metal structures; broad bands can be strongly absorbed by virtue of double-layer metal structures. The broadband wave-absorbing material can be used for radar stealth, electromagnetic compatibility, electromagnetic shielding and the like.

The present invention discloses an electromagnetic-wave absorption-material having a periodic structure. The material comprises magnetic-wave absorption-blocks and a dielectric material grid, wherein meshes on the dielectric material grid are through holes, and the magnetic-wave absorption-blocks are embedded in the through holes of the dielectric material grid according to a certain periodicity. The preparation method for the electromagnetic-wave absorption-material comprises the following steps: selecting a magnetic-wave absorption-raw material, and cutting the magnetic-wave absorption-raw material into a desired shape and a desired size to prepare into magnetic-wave absorption-blocks; selecting a dielectric material with a dielectric constant in a preset requirement range, arranging insert holes on the dielectric material in a periodic arrangement manner to obtain a dielectric material grid; and individually embedding the magnetic-wave absorption-blocks into the insert holes arranged on the dielectric material grid, and adopting an adhesive to connect the magnetic-wave absorption-blocks and the dielectric material grid into the integration to obtain the electromagnetic-wave absorption-material having the periodic structure. According to the present invention, the work bandwidth of the wave absorption material can be effectively expanded without increase of the thickness, and the volume density of the magnetic-wave absorption-material can be substantially reduced.

The invention discloses a carbonyl iron / graphene / polyvinylpyrrolidone compound wave-absorbing material, a preparation method thereof and the prepared wave-absorbing plate prepared by the method. The carbonyl iron / graphene / polyvinylpyrrolidone compound wave-absorbing material comprises a carbonyl iron powder core layer, a reduction-oxidation graphene layer which is coated on the periphery of the carbonyl iron powder core layer and a polyvinylpyrrolidone layer which is coated on the periphery of the reduction-oxidation graphene layer. The carbonyl iron / graphene / polyvinylpyrrolidone compound wave-absorbing material disclosed by the invention is characterized by simple preparation process, strong electromagnetic wave absorption capacity, wide frequency bandwidth, low cost and important application value in the fields of microwave absorption, electromagnetic leakage solution, electromagnetic shielding, and the like.

The invention discloses a zirconium and titanium-co-doped barium ferrite wave-absorbing powder material. The chemical formula is BaFe(12-x)ZrxTixO19, wherein x is equal to 0.2-0.4. The zirconium and titanium-co-doped barium ferrite is single-phase polycrystalline powder, and Fe<3+> and Fe<2+> exist in the barium ferrite at the same time. A preparation method comprises the following step of preparing the zirconium and titanium-co-doped barium ferrite wave-absorbing powder material by virtue of a self-propagating combustion method which is combined with ball-milling and a sequential secondary vacuum high-temperature thermal treatment process. The wave-absorbing material disclosed by the invention has the characteristics of being strong in absorption loss, wide in wave absorbing bandwidth, thin in match thickness and wide in modulated wave-absorbing frequency range. The effective wave absorbing bandwidth is controlled in a frequency range of 18-40GHz, double absorption peaks appear, the maximum absorbing bandwidth can reach 16GHz, the optimum match thickness is just about 1mm, and the optimum reflection loss RL value at the special frequency can reach about -48dB. The barium ferrite wave-absorbing powder material is simple in preparation process, can be used for a wave-absorbing coating, and can be widely applied to the fields of electromagnetic shielding and stealth.

The invention discloses a dielectric-based broadband tunable metamaterial wave-absorbing body and relates to the field of wave-absorbing materials and metamaterials. An electromagnetic wave-absorbingunit is formed by combining a soil material with a dielectric substrate on which a conductive thin film is pasted; and impedance matching is achieved through the electromagnetic wave-absorbing unit and a free space to achieve a relatively good wave-absorbing effect. The metamaterial wave-absorbing body is formed by periodically arranged wave-absorbing units and comprises the dielectric substrate,the soil material and the conductive thin film clung to the dielectric substrate. Square holes which are circular in inside are firstly engraved into the dielectric substrate, and then the soil material is embedded into the holes of the dielectric substrate and is in contact with the conductive thin film. By using the characteristic that the soil material has a high dielectric loss along with thechange of the water content in a microwave frequency band, the wave-absorbing bandwidth can be significantly increased under the condition of a relatively small thickness; main raw materials are easyto obtain and the metamaterial wave-absorbing body is eco-friendly, simple in structure, mature in preparation process, low in cost and suitable for large-scale production; and the wave-absorbing effect of the metamaterial wave-absorbing body can be adjusted through changing the water content of the soil material, so that operation is more convenient and concise.

The invention discloses an adjustable-frequency broadband meta-material wave-absorbing structure, and mainly solves a problem that the adjustable frequency of a broad wave-absorbing frequency band is difficult to achieve in the prior art. The structure mainly comprises a resonance structure (1), a dielectric substrate (2), and a metal floor (3). The resonance structure (1) and the metal floor (3) are respectively located at the upper and lower surfaces of the dielectric substrate (2). The resonance structure (1) consists of a metal square ring (4), a rectangular metal piece (5), a resistor (6), and an inductor (7). The opening of the metal square ring (4) is distributed in a manner of 90-degree rotary symmetry. The rectangular metal piece (5) is symmetrically distributed at the outer side of the metal square ring (4), and is parallel to the corresponding edge of the metal square ring (4). The resistor (6) is located at the opening of the metal square ring (4). The inductor (7) is connected with the corresponding edges of the rectangular metal piece (5) and metal square ring (4). Through the change of resistance and inductance, the structure achieves the continuous and adjustable frequency of a broad wave-absorbing band.

The invention relates to a wave-absorbing metamaterial comprising a plurality of metamaterial sheet layers. Each metamaterial sheet layer comprises a base material and a plurality of artificial microstructural groups which are attached to the base material and arranged in an array. Each of the artificial microstructural groups and the portion, occupied by each artificial microstructural group, of the base material are defined as a metamaterial unit. The artificial microstructural group on each metamaterial unit comprises more than one kind of artificial microstructural element. By means of the coupling of the various kinds of the artificial microstructural element of the multiple layers of artificial microstructural groups, the electromagnetic waves within a wide frequency range can be not reflected as much as possible and enter the inside of the wave-absorbing metamaterial to the maximum extent. In addition, high losses are produced by means of the resonance of the wave-absorbing metamaterial, so that the incoming electromagnetic waves can be attenuated rapidly in large amounts and transformed into heat energy or other energy and the wave-absorbing bandwidth of the wave-absorbing metamaterial is improved.

The present invention discloses a segmented wave-absorbing honeycomb sandwich composite material with a corrugated structure, which is formed by a wave-absorbing honeycomb and matching panels arrangedon upper and lower sides of the wave-absorbing honeycomb. The wave-absorbing honeycomb is made of a honeycomb core material segmentally impregnated with a wave-absorbing adhesive solution; an impregnated layer of the wall of the wave-absorbing honeycomb is of a corrugated structure; the matching panels on the upper and lower sides are glass steel plates; and the wave-absorbing honeycomb sandwichcomposite material is of a sandwich structure, with the wave-absorbing honeycomb and the matching panels being bonded with a prepreg which is molded by an autoclave process. The present invention provides a segmented wave-absorbing honeycomb sandwich composite material with a corrugated structure and a preparation method thereof, wherein a honeycomb core material is segmentally impregnated at thetop and the bottom with a prepared wave-absorbing adhesive solution and a corrugated structure is prepared by using a self-designed mold, so that the prepared wave-absorbing honeycomb sandwich composite material has the characteristics of light weight, small thickness, wide absorption band, high bearing capacity and the like.

The invention belongs to the technical field of electromagnetic noise absorption, and discloses a heat-conductive electromagnetic noise suppression sheet and a preparation method thereof, the heat-conductive electromagnetic noise suppression sheet comprises an organic silicon resin-based wave-absorbing medium top layer, an organic silicon resin-based wave-absorbing medium bottom layer, and an electromagnetic band gap structure layer embedded between the organic silicon resin-based wave-absorbing medium top layer and the organic silicon resin-based wave-absorbing medium bottom layer; each organic silicon resin-based wave-absorbing medium layer is an organic silicon resin and electromagnetic wave absorber composite; the electromagnetic band gap structure layer comprises a plurality of metalfoil grids and a wave-absorbing medium layer, the metal foil grids are uniformly distributed and fixed on the wave-absorbing medium layer; a heat conduction network is constructed in an organic silicon resin-based wave-absorbing medium by use of an electromagnetic band gap structure, by use of electromagnetic wave regulation characteristics, wave absorbing ability is enhanced, the thermal conductivity and the electromagnetic noise suppression capability of the heat-conductive electromagnetic noise suppression sheet can be significantly improved, and the wave-absorbing bandwidth and the centerfrequency loss intensity are significantly improved compared with the existing heat-conductive electromagnetic noise suppression sheet.

The invention provides a composite wave-absorbing material with rare earth element-doped magnetic particles loaded on layered MXene. The composite wave-absorbing material is prepared from a rare earth element-containing compound, a magnetic element-containing compound and an MAX phase. The composite wave-absorbing material is endowed with a wider wave-absorbing frequency band and more excellent wave-absorbing performance through doping of the rare earth element. Meanwhile, due to the introduction of rare earth element, the composite wave-absorbing material has relatively low density. The preparation method of the composite wave-absorbing material is simple, the preparation process is safe and free of toxic and harmful substances, and the composite wave-absorbing material has wide application prospects.

The invention provides a low-temperature curing high-temperature-resistant wave-absorbing coating and a preparation method thereof, and relates to the field of radar wave-absorbing functional coatings. The high-temperature-resistant wave-absorbing coating is prepared by taking methyl phenyl organic silicon resin or modified methyl phenyl organic silicon resin as an adhesive, alloy powder subjected to ball milling treatment as an absorbent and silicon-nitrogen oligomer as a curing agent, and adding a solvent, an auxiliary agent, a toughening agent and the like. The wave-absorbing coating has relatively high temperature tolerance, can resist 400 DEG C for 100 hours, can be cured at the temperature less than 80 DEG C, has relatively small reflectivity change before and after high temperature, has relatively high adhesive force and flexibility, and can solve the problems of low high temperature resistance, short temperature resistance time, high curing temperature, poor mechanical property and high coating hardness after curing of the existing wave-absorbing coating.

The invention belongs to the field of electromagnetic wave absorbing materials, and discloses a wave-absorbing patch with a periodic structure and a preparation method thereof. The wave-absorbing patch with the periodic structure comprises a plurality of periodic units 3. Each periodic unit 3 comprises a unit 1 and a unit 2, wherein the unit 1 comprises the following components in percentage by weight: 10%-25% of a polymer binder, 60%-75% of Fe-Si-Al soft magnetic alloy magnetic powder, 15%-30% of carbonyl iron powder and less than or equal to 1% of auxiliary materials; and the unit 2 comprises the following components in percentage by weight: 30-60% of polymer binder, 35-65% of conductive carbon black, 5-15% of silicon dioxide and less than or equal to 2% of assistant. Compared with a traditional wave-absorbing magnetic sheet, the wave-absorbing patch provided by the invention has better electromagnetic wave absorption performance through unique periodic unit design and component andpreparation process design of each unit, and the wave-absorbing frequency of the patch is broadened.

The invention discloses a water-solution-based broadband wave-absorbing metamaterial and relates to the technical field of electromagnetic functional materials. The water-solution-based broadband wave-absorbing metamaterial comprises an electrically-conductive reflecting layer, a dielectric matrix layer and a periodic array layer which are laminated sequentially from bottom to top, the dielectric matrix layer is composed of a composite frame and deionized water injected into the composite frame, the thickness of the composite frame is 0.8-3.5 mm, injection depth of the deionized water is 0.5-1.5 mm, the deionized water contacts with the upper surface of the electrically-conductive reflecting layer, and the periodic array layer is arranged on the top surface of the composite frame and is formed through arrayed arrangement of metal patches. The water-solution-based broadband wave-absorbing metamaterial has the advantages that with the aid of frequency dispersion characteristics of a water solution in a microwave frequency band, the metamaterial is capable of remarkably widening a wave-absorbing bandwidth without being thickened, and is simpler in structure, mature in preparation technology, easily available to raw materials, low in cost and easy for large-scale production and application.

The invention relates to a preparation method of magnetic wave-absorbing resin. The preparation method comprises the following steps: mixing a magnetic absorbent and graphene according to a mass ratioof (20-200): 1, carrying out ball milling to prepare a composite modified material, mixing the composite modified material with resin and a resin curing agent, and carrying out curing to obtain the magnetic wave-absorbing resin. According to the preparation method, the magnetic absorbent and the graphene are compounded to form a conductive network in the magnetic wave-absorbing resin, so electromagnetic loss is enhanced, the density of the wave-absorbing resin is reduced, the wave-absorbing performance of the wave-absorbing resin is improved, and the wave-absorbing bandwidth of the wave-absorbing resin is broadened. The preparation method provided by the invention is simple and feasible in operation, mature and stable in process, low in production cost and capable of realizing large-scaleproduction.

The invention discloses a novel wave-absorbing function design with material and structure wave-absorbing functions being integrated. A thick film characteristic of SU-8 novel negative photoresist is utilized; wave-absorbing materials and the SU-8 photoresist are combined, and micro-electronic technique means is utilized to perform patterning and a periodic structure is formed; and then the area outside the developed photoresist structure is filled with wave-absorbing materials based on wave-absorbing characteristic demands, and thus the wave-absorbing functions of the double materials and double structures are expressed. The thick film characteristic of the SU-8 photoresist is utilized and a patterning method is utilized to give play to the double wave-absorbing function of the materials and the structure; the novel wave-absorbing function design has the technical features of wide structure variable range and large material selection freedom; and the novel wave-absorbing function design facilitates the optimization design of a wave-absorbing system, and helps to improve wave-absorbing bandwidth and efficiency.

The invention relates to the field of high-temperature-resistant wave-absorbing materials, and particularly discloses an elevator degree distribution silicon carbide fiber reinforced ceramic-based ultra-wideband wave-absorbing composite material. The composite material, starting from the incident direction of the electromagnetic wave, sequentially comprises a first high-resistance silicon carbide fiber reinforced ceramic matrix composite material layer, a first lossy silicon carbide fiber array reinforced ceramic matrix composite material layer, a second high-resistance silicon carbide fiber reinforced ceramic matrix composite material layer, a second lossy silicon carbide fiber array reinforced ceramic matrix composite material layer, a third high-resistance silicon carbide fiber reinforced ceramic matrix composite material layer, a third lossy silicon carbide fiber array reinforced ceramic matrix composite material layer and a fourth high-resistance silicon carbide fiber reinforced ceramic matrix composite material layer; and the lossy silicon carbide fiber array is composed of two-dimensional fiber cloth patch units arranged in a periodic array mode, the periodic units are the same in size, the patch sizes are sequentially increased, and the sheet resistance is sequentially reduced. The wave-absorbing bandwidth of the wave-absorbing composite material is remarkably improved, the wave band of 340 GHz can be covered, and the wave-absorbing performance is excellent.

The invention provides a preparation method and application of the microwave absorbing composite material used as coating or a packing layer and relates to a preparation method and application of a microwave absorbing composite material. The preparation method is used for solving the problem that a microwave absorbing composite material prepared by adopting the prior art is single in microwave absorbing frequency, narrow in microwave absorbing bandwidth and low in microwave absorbing decibel. The preparation method of the microwave absorbing composite material comprises the following steps: firstly, preparing a polyethylene glycol 600 / dispersing solvent mixed liquor; secondly, preparing a mixed liquor A; thirdly, carrying out ball milling; fourthly, carrying out ultrasonic treatment; fifthly, preparing a mixture B; sixthly, carrying out ultrasonic treatment; seventhly, solidifying and curing. The microwave absorbing composite material used as the coating or packing layer can be taken as a coating coated on the surface of a composite material or a packing layer packed into an interlayer of a composite material structure. The prepared microwave absorbing composite material used as the coating or packing layer has obvious microwave absorbing property and can be applied to the fields of aviation, communication and military. By adopting the preparation method provided by the invention, the microwave absorbing composite material used as the coating or packing layer can be obtained.

The invention discloses a resistance loading square ring ultra-wideband wave-absorbing structure which comprises a surface skin dielectric layer, an impedance matching dielectric layer, a resistance loading square ring functional layer, a functional layer substrate, a structure supporting dielectric and a conductive reflecting layer which are sequentially arranged from top to bottom. The resistor loading square ring functional layer is composed of N * N square ring loops, each square ring loop is composed of a plurality of conductive square plates and a plurality of resistors, the conductive square plates are connected through the resistors to form a closed loop of the square rings, and the conductive square plates and the resistors are evenly distributed on the loop. The resistor loading square ring ultra-wideband wave-absorbing structure is simple in structure, wide in wave-absorbing frequency band and efficient in wave-absorbing performance, ultra-wideband high-performance electromagnetic wave absorption can be achieved, and the resistor loading square ring ultra-wideband wave-absorbing structure has wide application prospects in the fields of stealth technology, RCS reduction, electromagnetic compatibility design and the like.

The invention relates to the field of high-temperature-resistant wave-absorbing materials, and specifically discloses a silicon carbide fiber-reinforced ceramic-based ultra-broadband wave-absorbing composite material with an electric gradient distribution. Starting from the incident direction of electromagnetic waves, the first high-resistance silicon carbide fiber-reinforced ceramic-based composite material is sequentially included. Material layer, the first lossy silicon carbide fiber array reinforced ceramic matrix composite material layer, the second high resistance silicon carbide fiber reinforced ceramic matrix composite material layer, the second lossy silicon carbide fiber array reinforced ceramic matrix composite material layer, the third high The resistance silicon carbide fiber reinforced ceramic matrix composite material layer, the third lossy silicon carbide fiber array reinforced ceramic matrix composite material layer, the fourth high resistance silicon carbide fiber reinforced ceramic matrix composite material layer; the lossy silicon carbide fiber array is periodic Composed of two-dimensional fiber cloth patch units arranged in an array, the size of the periodic unit is the same, the size of the patch increases sequentially, and the square resistance decreases sequentially. The wave-absorbing composite material of the present invention has significantly improved wave-absorbing bandwidth, can cover the 3-40 GHz band, and has excellent wave-absorbing performance.

The invention discloses an electromagnetic wave absorbing material prepared on the basis of MXene waste precipitates as well as a preparation method and application of the electromagnetic wave absorbing material, and belongs to the technical field of nano materials and electromagnetic wave absorbing materials. The invention provides an electromagnetic wave absorbing material obtained on the basis of MXene waste precipitates, which is obtained by taking the MXene waste precipitates left after MXene is prepared by MAX phase etching as raw materials, collecting, drying and carbonizing. The carbonization treatment comprises the steps of putting the dried MXene waste precipitates into a crucible, putting the crucible into a tubular furnace, and carbonizing for 1-5 hours at the temperature of 400-1000 DEG C in an N2 atmosphere so as to obtain the electromagnetic wave absorbing material. The invention also provides a preparation method and application of the electromagnetic wave absorbing material. The method disclosed by the invention is simple, secondary utilization is performed on the MXene waste precipitate, and the wave-absorbing performance and the wave-absorbing bandwidth of the wave-absorbing material are effectively improved.

A camouflaged wave-absorbing blanket, which includes a wave-absorbing layer and an adhesive layer, the wave-absorbing layer includes a base cloth, and is characterized in that, on the plane of the base cloth, a plurality of plants are arranged along the first direction and the second direction respectively A wave-absorbing beam composed of metal fiber yarns, the lower part of the wave-absorbing beam is vertically passed through the base cloth by the upper surface of the base cloth and at least part of the lower part of the wave-absorbing beam is fixed on the lower surface of the base cloth through an adhesive layer, and the upper part of the wave-absorbing beam is free end. The camouflaged wave-absorbing blanket provided by the invention has a wide wave-absorbing frequency and low reflectivity, and can be applied to the protection of weapon equipment as a concealed protective cover.

The invention discloses a core-shell Ni / Co alloy and nitrogen-doped carbon-based wave-absorbing composite material and a preparation method thereof.The preparation method comprises the steps that firstly, a Ni / Co-MOF precursor is prepared through a simple hydrothermal reaction, and then the core-shell Ni / Co-C composite wave-absorbing material is obtained through high-temperature treatment in an argon inert environment; when the thickness of the composite wave-absorbing material is 3.5 mm, the frequency is 8.9 GHz, and the optimal effective wave-absorbing bandwidth (RL) value can reach-71.9 dB, RLlt; the effective wave-absorbing bandwidth of-10 reaches up to 16 GHz, S, C, X and Ku frequency bands are covered, and due to the fact that a core-shell structure with nickel and cobalt wrapped by carbon is formed, the material has good stability. The wave-absorbing material prepared by the method disclosed by the invention is environment-friendly, good in stability, relatively wide in wave-absorbing bandwidth, high in reflection loss, simple in process and suitable for large-scale production.

The invention provides an ultrahigh-frequency and ultra-wide-band composite electromagnetic wave-absorbing structure. The wave-absorbing material can achieve the radiation suppression effect of 10 dB or above at 20-30 GHz, and the wave-absorbing effect is obviously improved compared with the wave-absorbing effect obtained by independently using a commercial wave-absorbing material. The ultrahigh-frequency and ultra-wide-band composite electromagnetic wave-absorbing structure comprises a plurality of wave absorbing units which are arranged periodically; each wave absorbing unit comprises a top layer, a middle layer and a bottom layer which are sequentially arranged from top to bottom, the bottom layer is a metal back plate, the middle layer is a commercial electromagnetic wave-absorbing material, and the top layer is a Rogers RO4725JXR material.

The invention provides a preparation method and application of the microwave absorbing composite material used as coating or a packing layer and relates to a preparation method and application of a microwave absorbing composite material. The preparation method is used for solving the problem that a microwave absorbing composite material prepared by adopting the prior art is single in microwave absorbing frequency, narrow in microwave absorbing bandwidth and low in microwave absorbing decibel. The preparation method of the microwave absorbing composite material comprises the following steps: firstly, preparing a polyethylene glycol 600 / dispersing solvent mixed liquor; secondly, preparing a mixed liquor A; thirdly, carrying out ball milling; fourthly, carrying out ultrasonic treatment; fifthly, preparing a mixture B; sixthly, carrying out ultrasonic treatment; seventhly, solidifying and curing. The microwave absorbing composite material used as the coating or packing layer can be taken as a coating coated on the surface of a composite material or a packing layer packed into an interlayer of a composite material structure. The prepared microwave absorbing composite material used as the coating or packing layer has obvious microwave absorbing property and can be applied to the fields of aviation, communication and military. By adopting the preparation method provided by the invention, the microwave absorbing composite material used as the coating or packing layer can be obtained.

The invention discloses a light transmitting structured broadband wave absorbing material with water acting as the loss medium, and belongs to the technical field of the wave absorbing material. The structured broadband wave absorbing material comprises a loss medium loading device and a bottom backboard. The loss medium loading device and the bottom backboard form an enclosed structure. The lossmedium loading device is filled with the loss medium. The loss medium loading device is made of transparent material. The loss medium is the deionized water. The bottom backboard is the ITO conductivefilm backboard. The bottom part of the loss medium loading device is also provided with two through holes used for injecting and draining the deionized water. The deionized water is used as the lossmedium so that the wave absorbing bandwidth can be obviously extended without increasing thickness. The selected component material has the characteristic of high light transmittance in the visible light band so that the formed wave absorbing material is enabled to have the characteristic of high light transmittance.

The invention discloses a water-solution-based broadband wave-absorbing metamaterial and relates to the technical field of electromagnetic functional materials. The water-solution-based broadband wave-absorbing metamaterial comprises an electrically-conductive reflecting layer, a dielectric matrix layer and a periodic array layer which are laminated sequentially from bottom to top, the dielectric matrix layer is composed of a composite frame and deionized water injected into the composite frame, the thickness of the composite frame is 0.8-3.5 mm, injection depth of the deionized water is 0.5-1.5 mm, the deionized water contacts with the upper surface of the electrically-conductive reflecting layer, and the periodic array layer is arranged on the top surface of the composite frame and is formed through arrayed arrangement of metal patches. The water-solution-based broadband wave-absorbing metamaterial has the advantages that with the aid of frequency dispersion characteristics of a water solution in a microwave frequency band, the metamaterial is capable of remarkably widening a wave-absorbing bandwidth without being thickened, and is simpler in structure, mature in preparation technology, easily available to raw materials, low in cost and easy for large-scale production and application.

The invention discloses a broadband ultrathin transparent wave absorber design, which comprises an ITO film and a plurality of wave absorbing units, the bottom of the ITO film is fixedly provided with the plurality of wave absorbing units, and each wave absorbing unit is composed of three ultrathin resistive film resonators, three polyethylene glycol terephthalate (PET) films and three polyvinyl chloride films. The three ultra-thin resistive film resonators are uniformly deposited on the tops of the three polyethylene glycol terephthalate (PET) films, the ultra-thin resistive film resonator on the top and the ultra-thin resistive film resonator in the middle are separated by a polyvinyl chloride film, and the thickness range of the polyvinyl chloride film is 2.5-3.5 mm. The ultra-wide-spectrum wave-absorbing material is designed on the basis of the double wave-absorbing structure layers and in combination with the square resistance of the resistive film, wave-absorbing peaks at low frequency, intermediate frequency and high frequency are achieved by reasonably selecting the surface resistance value and structure parameters of the resistive film, the low-frequency absorption strength is enhanced, the overall wave-absorbing bandwidth is widened, and the wave-absorbing performance at 4.6-24.4 GHz can be smaller than-10 dB.