Radio-absorbing diffraction grating-based coating

FIELD: radio engineering, communication.

SUBSTANCE: diffraction grating-based coating is made of electroconductive or dielectric material, containing radio-absorbing elements. Coating includes groups containing, at least, four slots, each slot in the group is parallel to each other, each group is perpendicular in relation to the other group. Slots have a distance between adjacent elements from one sixteenth to one quarter of the length of the incident electromagnetic wave. Inside the slot there are not less than four layers of aramid fabric that are not interconnected, with a magnetron sputtered film of hydrogenated carbon with nanoclusters of metal atoms. The coating is protected from below from external exposure by metal foil, and from above - by means of a radio-transparent layer with a thickness of, at least, 0.1 mm. The above layers of aramid fabric with a magnetron sputtered film of hydrogenated carbon with nanoclusters of metal atoms are radio-absorbing elements.

EFFECT: increasing the stealth and reducing the likelihood of detecting objects of sea, land, aviation and space equipment by radar, ensuring the electromagnetic compatibility of radioelectronic and radio engineering devices and units, increasing the efficiency of absorbing electromagnetic radiation over a wide range of wavelengths.

1 dwg

 



 

Same patents:

FIELD: radio engineering, communication.

SUBSTANCE: invention relates to radio engineering, primarily to wideband radar-absorbent coatings. The wideband radar-absorbent coating is made in the form of an absorbing layer of material with dielectric permittivity ε=ε'+i·ε", magnetic permittivity and refraction index n, deposited on an electromagnetic wave reflecting surface, wherein the absorbing layer is made of material with the real part of the square of the refraction index less than zero Re(n2)=(ε2'μ2'ε2"μ2")<0.

EFFECT: reduced coefficient of reflection of electromagnetic waves in a wide frequency band.

5 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to materials which absorb electromagnetic waves, and can be used to improve stealthiness and reduce the probability of radar detection of ground, aircraft and space equipment and objects. A method of forming radar-absorbent topologies on carriers by depositing a working liquid on a carrier; with frequency forced perturbation of the jet of the working liquid, generating a linear stream of monodispersed droplets with diameter of 30-300 mcm, separated by a distance equal to the wavelength of the perturbation; transmitting a sign- and magnitude-controlled electric charge to a selected droplet, while deviating said droplet in an electrostatic field to a given point of the carrier to obtain nanostructured conducting configurations. The working liquids used are liquids which are nanosuspended in solvents and surfactants with metal nanoparticles with average diameter of 20-100 nm, the weight content of which is equal to 20-40%, with dynamic viscosity coefficient of the liquid less than 1000 cP, volume resistivity of 0.25-10 ohm·m and surface tension of (20-70) 10-3 N/m.

EFFECT: invention provides a contactless method of producing radar-absorbent topologies on a carrier, as well as high efficiency of the process.

4 cl, 2 tbl, 5 dwg

FIELD: electricity.

SUBSTANCE: invention is referred to the sphere of protection against electromagnetic interference (EMI) and may be used for protection of computer technology facilities (CTF) of information and communication systems against impact of external and stray electromagnetic radiation (SEMR). A multilayer honeycomb straightener is used with fabrication inhomogenuities made in the form of hollow rectangular prisms with cross-section shaped as staggered regular hexagons and of radar absorbent composite materials.

EFFECT: higher screen factor.

3 dwg

Ferrite material // 2540971

FIELD: chemistry.

SUBSTANCE: ferrite material is obtained from mixture of powders, containing Fe2O3, Li2CO3, MnCO3, Bi2O3, ZnO, CdO, SnO2, TiO2 with the following component ratio, wt %: iron oxide 71.39±0.1, lithium carbonate 5.61±0.1, zinc oxide 8.58±0.1, cadmium oxide 5.41±0.1, tin oxide 3.18±0.1, titanium oxide 0.69±0.03, manganese carbonate 4.84±0.1, bismuth oxide 0.3±0.03. Ferrite material is obtained in accordance with standard ceramic technology.

EFFECT: reduction of dielectric loss and increase of residual induction value in claimed material.

1 tbl

FIELD: radio engineering, communication.

SUBSTANCE: device consists of three layers: two outer construction layers and reinforcement plates are made of polymer composites, and the medium layer is from a lightweight filling material with reinforcement plates. The reinforcement plates and the outer base layers contain conductive materials with the surface resistance of 90÷1200 Ohm, providing for the absorption of falling electromagnetic waves and causing the reduction of a radio wave reflection in SHF S, C, X, Ku, Ka ranges from the device surface of polymer composites by 3÷5 times, and from a metallic surface - by 5÷50 times.

EFFECT: radar eluding device efficiency improvement due to the expansion of the frequency absorption range of falling electromagnetic waves.

2 cl, 2 dwg

FIELD: electricity.

SUBSTANCE: device comprises a dielectric case filled with a substance having conductivity and bioactive liquid is used as this substance, at least one polarized photon generator closed by a cover hermetically and installed in the dielectric case filled with bioactive liquid, and at least one tube installed hermetically in at least one opening made in the case cover, at that the tube is made of dielectric having positive value of static electricity surface charge. One end of the tube is submerged to the bioactive liquid while the other end is outputted from the case and closed by a plug of organic material transparent for photons and selected of the group consisting of resins of hardwood and softwood. The bioactive liquid enters into the tube partially.

EFFECT: improved efficiency of neutralisation of electromagnetic background.

13 cl, 3 dwg

FIELD: radio engineering, communication.

SUBSTANCE: invention relates to antenna engineering, particularly electromagnetic wave absorbers used in antenna structures to optimise radio properties thereof, eliminate resonance phenomena and reduce spurious reflections from conducting objects located near antennae. The electromagnetic wave absorber consists of epoxy-elastomeric binder in which magnetic filler is distributed - nanocrystalline powder in form of particles of an Fe-Cu-Nb-Si-B alloy with a nanocrystalline structure, the particles of the alloy containing nanocrystals of α-(Fe,Si) compounds with volume density of (2.8-2.9)·10-5 1/nm3, with the following ratio of components, pts.wt: epoxy elastomer 100; curing agent 10; nanocrystalline powder 200-700, wherein the nanocrystalline powder has particle size of 1 to 100 mcm.

EFFECT: use of the novel absorber reduces the reflection coefficient in the lower and upper parts of the UHF range, with a satisfactory reflection coefficient in the middle part of the range, and provides monotony of the beam shape of a small-size broadband antenna.

1 dwg

FIELD: electricity.

SUBSTANCE: formula contains 5-16 wt % of ultradisperse active carbon with an average size of particles of 5-100 nm and specific surface are of 16-320 m2/g, a dispersing agent in the form of soda glass aqueous solution and a stabilising agent in the form of a saturated solution of . Finely-dispersed colloidal graphite can be introduced into the formula additionally. The invention uses the formula property to absorb radio-wave electromagnetic radiation at its equal distribution inside the hard matrix of a constructional material or at its application onto the surface of radar absorbent structures or constructional materials.

EFFECT: improving radioprotective properties of the material is the technical result of this invention.

2 cl, 3 tbl

FIELD: radio engineering, communication.

SUBSTANCE: electromagnetic wave absorber for anechoic chambers and shielded rooms, having a spike-shaped hollow low-combustible housing made of single-face laminate, in the inner cavity of which there is a radar-absorbent filler, characterised by that the housing has the shape of a rectangular prism, wherein the ratio of sides which form a right angle to the thickness of the prism is equal to 6(±1):3(±0.5):1.

EFFECT: high efficiency of shielding.

3 dwg, 1 tbl

FIELD: physics.

SUBSTANCE: invention relates to the manufacturing of bulk microwave energy absorbers from high-temperature absorbent material, used in high-frequency channels of electronic equipment. The method of making bulk microwave energy absorbers involves making absorbers of the required configuration from ceramic workpieces by mechanical processing. To increase heat-conductivity of the absorbers and ensure stability of their radio characteristics, the obtained absorbers are saturated with a composition containing Elasil sealant 137-182, diluted with nefras in ratio of 1:1, at temperature of 25±10°C and pressure of 1.3-2.6 kPa for 30 minutes, and then at pressure of 300-400 kPa for 5-10 minutes, followed by drying at temperature of 25±10°C for 24 hours.

EFFECT: high heat-conductivity of the absorbers and ensuring stability of radio characteristics thereof.

1 tbl

FIELD: radio-electric engineering.

SUBSTANCE: cover is formed in form of layer on basis of fiber, placed between outer and inner layers of dielectric materials. Fiber layer along thickness is formed of several cloths of textile material of synthetic filaments with carbon cover with specific electrical, in which adjacent cloths are interconnected by inserts of given thickness on basis of dielectric connecting substance. Outer layer is made of rubber. Inner layer is made of dielectric connecting substance, containing granulated material, weakening reflection of electro-magnetic waves, in amount of 5-25% of total.

EFFECT: higher efficiency.

3 cl, 1 dwg

FIELD: composite materials.

SUBSTANCE: invention discloses a method for manufacturing composite material for shielding-mediated protection against electromagnetic emission and can be used in electronics, in radio engineering, and also in a series of special-destination articles. In addition, material may be used for anechoic boxes and in various assemblies of technical devices and radio apparatuses. Method comprises mixing modified graphite-containing conducting filler and polymeric binder at weight ratio (50-80):(20-50). Once ingredients combined, mixture is additionally subjected to thermal expansion in thermal shock mode at 250-310оС and then molded. Polymeric binder is selected from polyolefins, polystyrene, fluoroplastic, polyvinylchloride paste and modified graphite is product obtained by modifying graphite with concentrated sulfuric and nitric acids. Material is characterized by that, in wavelength band from 2 to 5 cm at thickness of material up to 0.1 mm, transmission coefficient is decreased from -40 to -85 dB.

EFFECT: improved performance characteristics.

6 cl, 1 tbl, 2 ex

FIELD: electromagnetic radiation protection.

SUBSTANCE: invention relates to a method of preparation and to composition of magneto-dielectric materials absorbing electromagnetic emission. Composition is prepared by combining binder with superdispersed magneto-dielectric filler, in particular composite product obtained through caking at 1150-1250°C followed by disaggregation of cake composed of magnetic particles of ferrite material (61.5-86.7 vol %) obtained by chemical precipitation of ferrite phase from aqueous solutions, the rest being layers of dielectric oxides precipitated onto surface of magnetic particles by way of nanomolecular layering from gas medium. Invention further discloses composition including 65-75 vol % of superdispersed magneto-dielectric filler along with binder prepared by above-indicated method.

EFFECT: increased choice of electromagnetic radiation-protection materials.

2 cl, 3 tbl, 12 ex

FIELD: electromagnetic radiation protection.

SUBSTANCE: invention relates to a method of preparation and to composition of materials absorbing electromagnetic emission. Composition is prepared by combining binder with ferrite, the latter containing 60-90% of ferrite material obtained according to high-temperature ceramic technology and ground to microparticle size and 10-40% of particles belonging to ferrite phase obtained by chemical precipitation from aqueous solutions onto surface of ferrite material microparticles. Ferrite is calcined in the form of isolated precipitate at 500-600°C and then disaggregated. Invention further discloses ferrite-based composition containing 9-13% binder obtained by above-indicated method.

EFFECT: increased choice of electromagnetic radiation-protection materials.

2 cl, 5 tbl, 12 ex

Ship // 2249535

FIELD: shipbuilding; devices reducing probability and range of detection of ship by enemy radar systems.

SUBSTANCE: ship has metal hull and superstructure which is made from multi-layer polymer composite material. Ratio of superstructure area to hull area shall be no less than 0.54; metal members built in superstructure are coated with radio-absorbing external layer. Open cavities in hull and in superstructure are provided with detachable shields made from material reflecting the radio waves. Provision is made for forming false radar targets for receiving enemy missiles and effective protection of personnel against radiation of own radar facilities.

EFFECT: enhanced efficiency and safety.

1 dwg

FIELD: antennae equipment.

SUBSTANCE: device is in form of a structure composed of cardboard pipe-like elements of various length and diameter and wedge-like inserts, positioned inside pipe-like elements. Said elements are gathered in blocks in parallel to their axis, have inner diameter 66 and 200.4 mm, one slant at 17 degrees angle or two slants symmetric to element axis at angle 35 degrees, outer and inner electric-conductive layer.

EFFECT: higher efficiency, broader functional capabilities.

8 cl, 11 dwg, 1 tbl

FIELD: radiation-absorbing coatings.

SUBSTANCE: proposed radiation-absorbing coating has rubber base three-layer flexible plate made of ferrite powder, content of the latter being different in each layer. Third layer has in its composition 10 - 15 volume percent of gralene fiber. Coating also has fourth layer abutting against metal surface of piece of equipment being protected which is made of magnetically hard rubber of arch-type magnetization whose magnetic energy corresponds to maximum of energy product (BH)max = 4 - 8 kJ/m3. Coating may have metal or ceramic magnets in fourth layer. Process for manufacturing radiation-absorbing coating includes production of each layer of plate, joining of three first layers by co-curing, magnetization of fourth layer, and installation of metal or ceramic magnets therein; fourth layer is magnetized by way of arch-type saturation whereupon this layer is attached to plate assembled of three first layers with aid of adhesive.

EFFECT: facilitated installation on and removal from machine armor, improved radiation absorbing properties within wide frequency band.

3 cl, 4 dwg, 1 tbl

FIELD: materials transmitting or trapping electromagnetic beams of definite wavelength and bandwidth for research and industrial applications.

SUBSTANCE: proposed method for producing membranes capable of passing or trapping electromagnetic radiation of definite wavelength λ and bandwidth Δλ to obtain frequency-selective membranes with any composite pattern on any insulating substrate and in any quantity includes coating insulating substrate with low-resistance paste of desired pattern. Used as low-resistance paste is low-viscosity stabilized conducting compound of ultra-dispersed powders, polymeric binder having steady electric conductivity and average particle size of 10 - 600 nm, organic solvent, and surface-active materials, proportion of ingredients being as follows, parts by mass: ultra-dispersed conducting powder, 60 - 90; polymeric binders, 39 - 7; organic solvent, 100 - 400; and surface-active materials, 1 - 3. This compound is applied by means of printer or plotter according to desired program to produce desired pattern whose layer thickness is not smaller than that of skin layer for final procedure, it is dried out.

EFFECT: enlarged functional capabilities.

1 cl, 2 tbl

FIELD: protection from electromagnetic emission.

SUBSTANCE: mesh of electric-conductive material is positioned on dielectric transparent film with applied transparent electric-conductive layer, made either of indium, or of tin, or of indium/tin alloy with thickness, approximately equal to 0,1 of skin layer, and the very mesh is applied with thickness not exceeding skin-layer by printer or plotter using electric-conductive compound, consisting of ultra-dispersive electric-conductive powder with stable electric conductivity and average size of particles 10,0-600,0 nm, polymer linking component, organic solvent and surfactant with certain ratio of components.

EFFECT: forming of transparent screens, screening properties of which do not depend on falling angle of electromagnetic emission, also light and simple to manufacture.

2 tbl

Absorbing coating // 2271058

FIELD: reduced probability of weapon and other war materiel location by radar.

SUBSTANCE: controllable layer is made in the form of thin film of evaporated graphite and disposed between first and second insulating layers; first bidimensional-periodic lattice made of evaporated metal strips is disposed on external side of first insulating layer; second bidimensional-periodic lattice made of evaporated metal strips is disposed between second and third insulating layers; other side of third layer carries reflecting screen; conductivity B1 of first bidimensional-periodic lattice and thickness d1 of first insulating layer ensuring minimal level of echo signal in desired frequency band are chosen from mathematical expressions given in description of invention. Thicknesses of second and third insulating layers d2 and d3 of second and third insulating layers, respectively' as well as refractive indices of first, second, and third insulating layers n1, n2 n3, respectively, are chosen from expressions given in description of invention.

EFFECT: reduced cost of coating.

1 cl, 5 dwg

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