49results about How to "Achieve stealth" patented technology

The invention discloses an antenna for reducing a radar scattering cross section, aiming to solve the problem of large radar scattering cross section of the traditional microstrip antenna. The antenna comprises a dielectric slab (1), a microstrip radiating unit (2) and an earth plate (3), wherein the microstrip radiating unit is arranged at the upper surface of the dielectric slab, and the earth plate is arranged at the lower surface of the dielectric slab; both sides of the microstrip radiating unit are provided with a high impedance surface array (4) respectively; each high impedance surface array is formed by arranging a plurality of metal chips into a rectangle, a gap is arranged between the adjacent metal chips to form a capacitor C; the center of each metal chip is provided with a metal via hole which penetrates through the dielectric slab; a current path connected by the via holes can form an inductor L, and the capacitor and the inductor form an LC resonant circuit; the frequency of the resonant circuit can be adjusted to be coincident with the working frequency of the antenna, thus realizing scattered field compensation of the high impedance surface array and the antenna. The invention has stable performance of reducing radar scattering cross section within and outside the frequency band of the antenna, and also has no effect on the size, weight and cost of the antenna.

The invention discloses a broadband bionic yagi antenna with a low radar cross section and mainly solves the problems of high radar cross section and relatively narrow band width in the traditional yagi antenna. The antenna simulates an opposite phyllotaxis plant leaf structure and comprises a director (2), a radiating element (3), a parallel strip line (4), a reflector (5) and a coaxial conversion joint (6). The radiating element (3) is of an oval structure, the director (2) simulates a feather-shaped leaf structure, and the reflector (4) is a rectangle patch with a tooth-shaped structure. The radiating element (3) is printed on a top layer and a bottom layer of a double-layer medium material plate (1) and respectively connected with an inner core and an outer core of the coaxial conversion joint (6) by the parallel strip line (4); the director (2) is printed on the top layer of the double-layer medium material plate (1); and the reflector (4) is printed between two layers of the double-layer medium material plate (1). The broadband bionic yagi antenna with the low radar cross section has the advantages of wide frequency band and good invisibility performance and can be used on an invisible target carrier.

The invention provides an airplane with a combined-wing layout of a flying wing and forward-swept wings. The airplane is characterized in that thin-wing type vertical columns A and B are additionally arranged at the 70% wingspan positions of the outer sides of two side wings of a flying-wing airplane with backward-swept wings, a thin-wing type vertical column C is additionally arranged at the tail part of the flying-wing airplane, and horizontal forward-swept wings are additionally arranged at the top ends of the three thin-wing type vertical columns A, B and C so as to form the combined-wing layout of the flying wing and the forward-swept wings; elevators are arranged on the horizontal forward-swept wings and a rudder is arranged on the vertical column C; a duct type air inlet channel is adopted on the upper wing surface of the flying wing, and cracking type drag rudders are distributed at the thin-wing type vertical columns A and B. The airplane provided by the invention has the advantages that under the condition that the structure strength is effectively guaranteed, the effective aspect ratio of the wings is increased, the induced drag is reduced, the lift-drag characteristics of the airplane are improved, the stealth performance of the airplane is improved, direct-force control of the airplane in the vertical direction is realized and the detecting accuracy under the maneuvering condition is improved.

The invention provides an ARP (Address Resolution Protocol) message processing method and device. The ARP message processing method comprises the following steps of: acquiring an ARP message; judging the type of the ARP message; and processing the ARP message according to the type of the ARP message: if the type of the ARP message is a broadcast packet transmitted out from a local machine, judging whether the broadcast packet is the ARP broadcast packet transmitted from the local machine to a gateway; if the broadcast packet is the ARP broadcast packet transmitted from the local machine to the gateway, modifying the ARP request into an ARP echo packet and transmitting the ARP echo packet to the gateway; if the broadcast packet is not the ARP broadcast packet transmitted from the local machine to the gateway, discarding the broadcast packet; if the type of the ARP message is the ARP echo packet, judging whether the ARP echo packet is the ARP echo packet transmitted from the local machine to the gateway; if the ARP echo packet is the ARP echo packet transmitted from the local machine to the gateway, transmitting the ARP echo packet to the gateway; and if the ARP echo packet is not the ARP echo packet transmitted from the local machine to the gateway, discarding the ARP echo packet. Through the invention, ARP message spoofing defense is realized without affecting surfing condition, and the security of the local area network is guaranteed.

The invention discloses a metal coating-based high temperature-resistant structural wave absorbing material and a preparation method thereof. The high temperature-resistant structural wave absorbing material is formed by coating a structural wave absorbing body with a high temperature-resistant fiber cloth; the structural wave absorbing body is formed by a group of structural wave absorbing body units or is formed by laminating two or more structural wave absorbing body units; and every structural wave absorbing body unit comprises a dielectric substrate layer and an impedance layer on the surface of the dielectric substrate layer. The preparation method comprises the following steps: sputtering a high temperature-resistant metal material onto the surface of the high temperature-resistantfiber cloth by using a magnetron sputtering process to obtain the impedance layer; covering the surface of the dielectric substrate layer with the impedance layer to obtain the group of structural wave absorbing units; and coating the group of structural wave absorbing body units or the plurality of laminated structural wave absorbing body units with the high temperature-resistant fiber cloth, andperforming stitching to obtain the high temperature-resistant structural wave absorbing material being able to withstand a high temperature of 700 DEG C or above, having good resistance to the high temperature and oxidation and having a wide wave absorbing bandwidth.

The invention discloses an ultra-wideband bionic antenna with a low radar scattering cross section, and mainly solves the problems that existing ultra-wideband antenna radar has high scattering crosssection and can be easily found by radar. The ultra-wideband bionic antenna with the low radar scattering cross section comprises a radiation unit (2), a radiant floor (3) and an SMA coaxial adapter substitute. The antenna radiating unit and the antenna radiation floor are respectively printed on both sides of a medium material board (1), and are respectively connected with an inner core (4) and an outer core (5) of the SMA coaxial adapter substitute. The radiating unit is designed to be a sectoral structure comprising a rectangular column and a plurality of arc strips symmetrically arranged on the rectangular column in accordance with a design thinking similar to insect antennae, the degrees of the central angles of the arc strips are identical, and the sizes of semi-diameters are progressively increased according to equal intervals from the top to the bottom; and both sides of the radiant floor are rectangles with inversed 90-degree arc angles. The invention has the advantages of wide frequency band and good hiding performance, thereby being capable of being used as the ultra-wideband antenna on a hiding target vector.

The invention provides an infrared ray camouflage coating, a camouflage production method utilizing the same and camouflage overcloth. The infrared ray camouflage coating has a good camouflage effect and further can achieve an infrared ray camouflage effect. According to the technical scheme, the infrared ray camouflage coating comprises a south forest type coating, a north forest type coating, a steppe type coating and a desert type coating. The camouflage overcloth comprises a shielding surface, wherein the shielding surface comprises an outer surface layer, an inner surface layer and base cloth.

The invention discloses a graphene containing infrared radar compatible stealth coating and a preparation method thereof. The graphene containing infrared radar compatible stealth coating comprises aresin system formed by mixing of resin, a solvent and an assistant, aluminum powder with conductivity and a radar wave reflection absorbent are dispersed in the resin system, and the radar wave reflection absorbent is composed of graphene with high dielectric constant and a magnetic absorbent. The dielectric properties of graphene are combined with electromagnetic properties of the magnetic absorbent to improve the reflection and absorption properties of the coating from two aspects of dielectric loss and electromagnetic loss, so as to achieve the effect of radar stealth' in addition, the graphene for radar absorption is dispersed among aluminum slurry particles in the resin system, the aluminum slurry particles are connected by the lamellar structure of the resin system to improve the conductivity of the coating, and low infrared emissivity is achieved; the coating can be used in high temperature radiation and radar bright spots of ships and warships, and can also be extended to ground equipment with high temperature position and radar stealth demand.

The invention belongs to the technical field of wave-absorbing materials, and discloses wave-absorbing composite foam and a preparation method thereof. An electromagnetic wave incoming surface comprises a glass fiber reinforced plastic layer, a wave-absorbing layer and a carbon fiber cloth reflecting layer sequentially from outside to inside, and an adhesive layer is arranged between the layers, wherein the wave-absorbing layer is obtained by (1) laying a layer of glass fiber cloth flatly; (2) applying a mixture of liquid thermosetting resin and curing agent onto the surface of the glass fibercloth by liquid electrostatic spraying; (3) vertically and directionally implanting a carbon wave-absorbing material on the basis of the step (2) by adopting an electrostatic flocking method; (4) forming a layer of hollow glass microspheres by powder electrostatic spraying; (5) continuously spraying a mixture of liquid thermosetting resin and curing agent; and (6) stacking a layer of glass fibercloth again on the basis of the step (5) to obtain the wave-absorbing layer. The wave-absorbing composite foam structure obtained herein allows weaponry to be efficiently invisible.

The invention discloses a system for guiding a laser radar for detection, and relates to the field of induction and anti-detection of the laser radar. The system comprises a laser reception and emission unit and a laser processing unit; the laser reception and emission unit receives laser signals, emitted by the laser radar, in the environment, and emits laser signals, processed by the laser processing unit, to the environment; and after receiving the laser signals, the laser processing unit attenuates or amplifies power of the received laser signals according to control requirements, and returns the attenuated or amplified laser signals to the laser reception and emission unit. The invention provides a method applied to the system for guiding the laser radar for detection at the same time. The system and method can be used to improve the active defense capability for radar detection effectively.

The invention belongs to the technical field of acoustics, and particularly relates to a time-domain broadband acoustic carpet type invisible garment and a manufacturing method. A broadband sound pressure local reflection theorem and a parameter optimization method are combined, a multilayer air square hole stacked structure is used as a metasurface basic structure unit, and a time domain broadband metasurface structure is designed through reverse optimization by the aid of a genetic algorithm. According to the designed time domain broadband metasurface structure, invisibility of sound waves within the frequency range of 2,000-5,500 Hz can be realized, the relative bandwidth is 93% or above, the invisible performance of the time domain broadband is displayed under multi-frequency pulse incidence, the limitation of narrow bandwidth of a traditional passive metasurface and the defect of adjustable metasurface time domain broadband are broken through, and a key research basis is providedfor the broadband acoustic metasurface structure design and the practical application of a broadband acoustic device.

The invention discloses an infrared stealth material with a multilayer structure. A core layer is hydrogel, and an auxiliary layer/auxiliary layers is/are added to one side or both sides of the core layer. The hydrogel has high specific heat capacity, and can absorb a large amount of heat on the premise of no significant change in temperature to achieve the function of heat buffering; the hydrogelserves as the core layer, so that the thermal infrared characteristics of covered objects can be reduced, and self-adaption to the environmental infrared radiation characteristics is realized to achieve infrared stealth. When the hydrogel serves as a cover, a heat-conductive fixing device is arranged on the edge of the infrared stealth material, and is communicated with a heat conducting layer toachieve controllable directional heat conduction; radar wave absorbing materials can be composited on any layer of the multilayer structure, and an infrared radiation and camouflage layer can be prepared at the outermost layer, so that infrared, radar wave and visual stealth is realized at the same time; the multilayer structure can be lined with breathable fabric to meet the air-permeability requirements of soldiers during long-time hiding. The infrared stealth material with high infrared, radar and visible-light stealth capability has the advantages of simple preparation process, low cost,portability and multifunction.

The invention provides an invisible glass shaping method which comprises the steps of determining the thickness D of a first transition layer according to the preset thickness and the thicknesses of afirst protection layer, a metamaterial structure layer, a radar wave reflection layer and a second protection layer; determining the thicknesses and dielectric constants of all layers of transparentmedia which form the first transition layer. The invisible glass shaping method disclosed by the invention can determine the thickness of the first transition layer in the invisible glass according torequirements of actual equipment, and can make the invisible glass reach the corresponding degree of invisible characteristic, thus meeting different equipment application requirements.

The invention discloses a satellite optical camouflage method. The satellite optical camouflage method comprises the steps that a customizing task of a luminosity curve needing a satellite to displayin an observation segmental arc is received; positions of the sun and a detector in a satellite centroid orbit coordinate system in the observation segmental arc is resolved and calculated; the direction of an angular bisector of a sun position vector and a detector position vector in the observation segmental arc is resolved and calculated; the number of normal directions of surface panel sand needing to turn to the direction of the angular bisector of the sun position vector and the detector position vector at the time in the observation segmental arc at all time is determined, wherein the surface panels are installed on the surface of the satellite; and a determined number of the surface panels are turned to the direction of the angular bisector of the sun position vector and the detector position vector, and the normal directions of a rest number of the surface panels are made to deviate from the direction by more than 30 degrees. According to the satellite optical camouflage method, the problem that a high orbit satellite avoids ground optical monitoring is solved, by covering the satellite surface with special secular reflection characteristic material surface panels, the reflection direction of the surface panels is controlled, and simulation on the detection of the customized detector for the luminosity curve of a target is achieved.

The invention relates to microwave-absorbing wind power blade coating as well as a preparation method and application thereof. The microwave-absorbing wind power blade coating comprises the following components in parts by weight: 70-99.9 parts of traditional blade coating and 0.1-30 parts of a carbon series microwave absorbing material. The preparation method of the microwave-absorbing wind power blade coating comprises the following steps: uniformly mixing 70-99.9 parts of the traditional blade coating and 0.1-30 parts of a carbon series microwave absorbing material; coating the obtained mixture onto a blade by adopting the traditional coating method. Compared with the prior art, the microwave absorbing wind power blade coating has anti-icing and deicing effects and can effectively reduce radar reflection.

The invention relates to a method and a device for realizing the cloaking of a mobile terminal, wherein the method executed by a mobile switching center comprises the following steps of: receiving information from the other device and for requesting to provide passive service for the mobile terminal; acquiring the state information of the mobile terminal, which is stored at a network side; judging whether the mobile terminal is in a cloaking state or not on the basis of the acquired state information; and when a judgment result is positive, stopping providing the passive service for the mobile terminal. The method and the device for realizing the cloaking of the mobile terminal enable users not to receive the passive service under the condition of using active service.

The invention relates to the technical field of antennas, and relates to a circularly polarized patch antenna shaped like a Chinese character 'jia'. The antenna includes a ground plate and a dielectric layer plate, wherein the ground plate and the dielectric layer plate are parallel to each other. The dielectric layer plate is arranged above the ground plate. A metal sheet A is arranged at the top of the dielectric layer plate, and a metal sheet B is arranged at the bottom. A 3D L-shaped probe is arranged between the ground plate and the dielectric layer plate. The 3D L-shaped probe consistsof a vertical rod and two horizontal rods of equal length. One end part of one horizontal rod and one end part of the other horizontal rod are fixedly vertically connected. The top of the vertical rodis fixedly connected with the common end part of two horizontal rods. Each horizontal rod is parallel to the dielectric layer plate. The vertical rod is perpendicular to the ground plate. The groundplate is provided with a through hole. The lower end of the vertical rod passes through the through hole and is connected with the coaxial connector arranged at the bottom of the ground plate. The ground plate and the dielectric layer plate are square, and the length of the sides is the same. The metal sheet A is shaped like a Chinese character 'jia'. The antenna provided by the invention has theadvantages of simple structure, low cost, beautiful appearance, safety and reliability.

The invention belongs to the field of artificial intelligence, and relates to a method for intelligent framing display on a screen and a mobile terminal. The problem that a display target cannot be accurately achieved through manual magnifying, framing, focusing and the like is solved. Space coordinates of human eyes are collected through a front depth sensor, the angle range of sight when the human eyes observe a screen is intelligently analyzed, automatic focusing framing is conducted through a mobile phone according to the known camera shooting angle range of a rear camera, the observationrange of the human eyes is intelligently intercepted, manual operation is not needed, and screen display is automatically adjusted. Human eye space coordinates are collected all the time, a screen does not need to be adjusted when a person moves, and intelligent framing is achieved; and when the frame is narrow enough, the screen is invisible, and an effect of mixing the false with the genuine isachieved.

The invention discloses a photonic crystal based on 3D printing and a preparation method thereof. The preparation method comprises the following steps that S1, slurry is prepared, the elasticity modulus of the slurry is larger than the viscous modulus, the slurry has viscoelastic inversion performance, the slurry is prepared from polydimethylsiloxane and a ceramic material, the slurry is divided into slurry A and slurry B; the dielectric constant of the slurry A is not equal to that of the slurry B; S2, a first crystal layer is formed from the slurry A and forming a second crystal layer from the slurry B by film-free direct-writing 3D printing equipment, and the first crystal layer and the second crystal layer are stacked to form a wood pile structure to obtain a photonic crystal semi-finished product; and S3, the photonic crystal semi-finished product is cured to obtain the photonic crystal. According to the preparation method, the process is simple, the prepared photonic crystal is high in precision, the stealth of terahertz waves with different frequency bands can be realized, and the applied wave band can be in a range of 10 GHz-10 THz.

The invention relates to infrared and radar compatible stealth window glass with sound insulation and heat insulation functions, which comprises outer-layer glass and inner-layer glass, wherein a vacuum layer is arranged between the outer-layer glass and the inner-layer glass, a microwave frequency selective surface structure array is arranged on the outer surface of the outer-layer glass, a microwave resonance absorption structure array is arranged on the inner surface of the outer-layer glass, and an electromagnetic reflecting film is arranged on the inner surface of the inner-layer glass. The window glass integrates a transparent supporting structure and a compatible stealth function, wide-spectrum efficient microwave absorption and low infrared emissivity can be achieved on the basis of the window glass, the microwave absorption range can cover 5-20 GHz, and the absorption efficiency is greater than 0.9. The infrared emissivity of the surface of the glass can be as low as 0.23, and the thermal radiation quantity of a target can be remarkably reduced, so that the probability of being detected is reduced. In addition, the visible light transmittance of the window glass is 60% or above. Meanwhile, based on the vacuum spacing layer in the structure, the window glass has sound insulation, noise reduction and heat insulation capacities.