17 results about "Microwave band" patented technology

The application relates to the technical field of infrared stealth, precise thermal control and electromagnetic compatibility, and particularly discloses a film system structure with visible ultra-high reflectivity, middle-infrared and far-infrared low emissivity and microwave high permeability; the medium stack layer has high reflectivity to visible light; the metal microstructure layer has low emissivity to middle-infrared and far-infrared light and high permeability to microwaves; the film system structure has visible light reflectivity greater than 60%, middle-infrared and far-infrared light emissivity lower than 30% and microwave permeability higher than 60%. The application realizes perfect compatibility of infrared stealth and microwave absorption, keeps infrared low emissivity (epsilon < 0.1) and realizes high permeability (greater than 95%) to 1-18GHz microwave bands. The application solves the thermal failure problem of the composite stealth structure, realizes average visible light reflectivity (greater than 95%) through the medium stack layer, greatly reduces the solar heat load and improves the overall optical performance.

This invention discloses a visible transparent, ultra-wideband microwave absorption structure, comprising, from top to bottom, a visible transparent spatial shielding layer, an impedance-gradient absorption layer, and a total reflection bottom layer. The spatial shielding layer is highly transparent to the microwave band. The impedance-gradient absorption layer is composed of multiple layers of low-dielectric-constant transparent dielectric substrates and an array of transparent conductive patterns disposed thereon, stacked alternately. The total reflection bottom layer is totally reflective to the microwave band. By precisely designing the gradient period and equivalent resistance of the multilayer transparent conductive pattern array, and utilizing the electromagnetic coupling and multi-point resonance mechanism of the upper and lower layers, this invention achieves ultra-wideband microwave strong absorption of more than 90% in the 1-40 GHz frequency band at the subwavelength scale, breaking through the bandwidth limitation bottleneck of traditional microwave absorbing structures; and it also possesses excellent visible light transparency characteristics.

This invention relates to the field of optical imaging technology, specifically providing an optical radar co-aperture off-axis imaging system, comprising: an off-axis mirror assembly, a frequency-splitting device, a radar transceiver system, and an optical imaging system. The frequency-splitting device is disposed in the rear optical path of the secondary mirror and is used to reflect light waves and transmit microwaves. The frequency-splitting device includes a frequency-selective surface, which comprises an FSS pattern layer and a bias line layer. The FSS pattern layer includes periodically arranged FSS units. Nonlinear capacitors are electrically connected to the FSS units. The bias line layer applies a voltage to the nonlinear capacitors according to the received microwave band. By changing the voltage applied to the nonlinear capacitors, the resonant frequency of the FSS units is tuned, thereby changing the microwave passband frequency of the frequency-splitting device. This invention not only achieves a reflective wave-transmitting microwave design but also solves the problem that transmitting only a single band of microwaves in microwave-transmitting and light-reflecting methods is difficult to adapt to different task requirements.

The application discloses a full dielectric film system structure of visible near-infrared low-transmission simulated vegetation, mid-infrared and microwave high-transmission, which comprises, from top to bottom, visible near-infrared simulated vegetation and a mid-infrared high-transmission layer and a substrate layer. The visible near-infrared simulated vegetation and the mid-infrared high-transmission layer are obtained by alternately stacking a first dielectric layer, a second dielectric layer, a third dielectric layer and a fourth dielectric layer, and the film layer close to the substrate layer is the fourth dielectric layer. The structure not only realizes high-spectrum simulation for vegetation in the 380-2500 nm wave band, but also maintains high transmission in the 3-5 mu m and 8-14 mu m wave bands, and has high transmission in the microwave wave band. The full dielectric film system structure of the application can also be compatible with other infrared regulation layers due to the infrared high-transmission characteristics, and the potential application extension of the film system is improved.

The present application relates to the technical field of electronic information functional ceramic materials and electronic devices, and particularly relates to a method for forming dielectric ceramic by microwave rapid annealing treatment, which comprises the following steps: (1) sample pretreatment, (2) microwave annealing, (3) cooling and discharging. The present application breaks through the limitation of heat damage caused by traditional process, and realizes the repair of non-intrinsic defects and intrinsic defects in the ceramic body by high-power microwave second-level transient annealing under the premise of completely maintaining the original grain size, crystal structure and phase composition of the ceramic, thereby fundamentally avoiding the problems of abnormal grain growth and volatilization of low-melting-point components, and realizing the lossless and rapid repair of defects of the formed dielectric ceramic. The processing period of traditional annealing lasting for several hours is shortened to 1-10 s, the process time is greatly shortened, and the quality factor Qxf of the dielectric ceramic after treatment is improved by 30%-100% in the terahertz band, and the quality factor Qxf is improved by 30%-60% in the microwave band.

To obtain a radio wave absorber that exhibits excellent radio wave absorption performance in the microwave band and can suppress the shedding of metal particles constituting the radio wave absorber compared to conventional materials. [Solution] The radio wave absorber 1 comprises a glass matrix 2 that maintains its shape and soft magnetic metal particles 3 that have radio wave absorption performance in the microwave band due to magnetic loss, and is made of a composite material in which the soft magnetic metal particles 3 are dispersed in the glass matrix 2. The average particle size of the soft magnetic metal particles 3 is 1 μm or more and less than 10 μm. The ratio of the volume of the soft magnetic metal particles 3 to the sum of the volumes of the soft magnetic metal particles 3 and the glass matrix 2 is 0.3 or more and 0.45 or less.

The application provides a bridge structure remote deformation and vibration measurement method and system based on microwave sensing, comprising the following steps: S1, estimating the position of the measured target by using imaging information; S2, phase-modulating the transmission signal of the transmission antenna according to the position of the measured target; S3, mixing the signal reflected by the target with a local oscillation signal and performing low-pass filtering to obtain a multi-channel baseband signal, and obtaining the deformation displacement information of the measured target through demodulation processing; and S4, extracting the deformation displacement information of the measured target through cyclic measurement. The application provides a high-integration, convenient-to-operate, and large-field-of-view monitoring method and system suitable for bad environments such as rainy and foggy days for bridge monitoring. The application arranges multiple transmitter antennas to synchronously transmit radio frequency signals, which are used for beam synthesis and scanning, so as to improve the energy and signal-to-noise ratio of the target reflected signal and realize long-distance measurement of the bridge based on the microwave band.

This invention provides a NiSiAlGd microwave absorbing material and its preparation method, relating to the field of microwave absorbing materials technology. The molecular formula of the NiSiAlGd microwave absorbing material is Ni... x Si 49.6 Al 5.4 Gd y The composition of the absorbing material is 37 < x ≤ 45 and 0 ≤ y ≤ 8. This absorbing material can absorb electromagnetic waves in the 2~18 GHz microwave band, with a wide effective absorption bandwidth and high absorption efficiency (>90%). The absorbing material has excellent thermal stability. At the same time, this invention provides a method for preparing the NiSiAlGd absorbing material mentioned above. The absorbing material can be obtained by arc melting, heat treatment and ball milling. The synthesis process is simple and suitable for large-scale industrial production.

The present application provides a kind of sea surface foam thickness remote sensing inversion method and system, for the L-Ka dual-band of sea surface foam coverage, foam thickness is cooperatively inverted, from the multi-band microwave radiation transmission characteristics, utilize the radiation characteristic difference of foam layer under different frequencies, establish the foam brightness temperature prediction model based on microwave band, the model considers the emission and scattering characteristics of the medium in foam layer, the emissivity of different thickness foam layer is calculated using radiation transfer equation.Then, the quantitative relationship between foam thickness and sea surface wind speed is established, by coupling sea surface foam model and wave spectrum model, sea surface foam coverage, thickness inversion is realized.The method and system provided by the present application can break through the limitation of traditional hydrodynamic model, realize large-scale, high spatio-temporal resolution observation of sea surface foam thickness, provide a new observation method for in-depth understanding of sea-air interface dynamics process.

The application provides a non-Hermite super surface and a construction method thereof, the non-Hermite super surface comprising a composite layer and a complementary layer coupled with the composite layer, a medium layer being arranged between the composite layer and the complementary layer; the composite layer is hollowed out to be provided with a plurality of hollow cylinders; the complementary layer is hollow at positions corresponding to solid portions of the plurality of hollow cylinders. By adjusting the structural parameters and selecting the material types, the composite layer and the complementary layer are coupled, so that the device realizes the influence on the reflection of the incident electromagnetic wave in the microwave band, and by changing the conductivity of the cited vanadium dioxide in the composite layer, the non-Hermite super surface appears singular points at two different frequency points, realizes the regulation and control of the non-Hermite super surface, effectively widens the application range of the non-Hermite super surface, and is more conducive to realizing the functionalization, device integration and application of the non-Hermite super surface.

The application relates to the technical field of non-contact humidity sensors, and discloses a non-contact microwave humidity sensor based on a dielectric material whispering gallery mode, which comprises a resonant cavity base and a top cover connected to the top of the resonant cavity base, and the resonant cavity base and the top cover jointly form an electromagnetic shielding chamber; further comprising a ring resonator made of low-loss dielectric material, a support frame supported in the ring resonator and connected to the bottom wall of the resonant cavity base; the sensor combines the mature high-Q value WGM principle of the optical wave band with the sensing application of the microwave wave band, creatively utilizes the intrinsic advantages and evanescent field sensing mechanism of the low-loss dielectric material, realizes millisecond-level ultrafast response, eliminates the risk of performance attenuation or failure of the sensitive coating, can effectively identify slight loss disturbance, and improves the detection precision.

This invention discloses a patterned reflective film and its fabrication process, belonging to the field of optical functional thin film technology. The reflective film includes a substrate layer and a reflective layer. The reflective layer is patterned to form a discontinuous reflective pattern, which includes reflective units separated by light-transmitting regions. The linewidth of the light-transmitting regions is 3-10 micrometers, and the reflective pattern can be a random grid or a gradient pixel array. This invention, by precisely designing the geometric distribution of reflective units and light-transmitting regions at the micrometer scale, utilizes the significant difference between microwave and visible light wavelengths to achieve high reflectivity in the visible light band and high transmittance in the microwave band. This fundamentally solves the contradiction between metallic decorative finishes and wireless signal transmission. The random or gradient pattern design effectively avoids moiré patterns with display pixels. The blackening process on the copper reflective layer surface can achieve various decorative colors such as blue, red, and black. This reflective film has a high yield and wide application.

The application discloses a kind of dynamic tracking microwave resonance cavity parameter device and method, belong to cigarette process quality inspection technical field, the device of the present application includes industrial computer, microwave signal source module, first isolator, microwave resonance cavity, second isolator and microwave detection module;Industrial computer, microwave signal source module, first isolator, microwave resonance cavity, second isolator and microwave detection module are sequentially connected by line;The method of the present application includes the following steps: determine whether the device is in idle state, if in non-idle state, then wait until idle;The cavity of microwave resonance cavity is swept frequency;Calculate the parameter of microwave resonance cavity cavity state;Next time measurement is based on the last resonance cavity cavity parameter setting this measurement microwave band.Utilize the idle time of system to calculate the cavity parameter of microwave resonance cavity to achieve the purpose of dynamic tracking, improve the calculation precision, and the cavity parameter of microwave resonance cavity can be accurately obtained.

This invention provides a CrNbRuNi microwave absorbing material and its preparation method, relating to the field of microwave absorbing materials technology. The CrNbRuNi microwave absorbing material has the chemical formula Cr2NbRu2-xNix, where 0≤x≤0.3. This composition of microwave absorbing material can absorb electromagnetic waves in the 2–18 GHz microwave band, with a wide effective absorption bandwidth and high absorption efficiency (>90%). The material also exhibits excellent thermal stability. Furthermore, this invention provides a method for preparing the aforementioned CrNbRuNi microwave absorbing material. The material can be obtained through arc melting, heat treatment, and ball milling. The synthesis process is simple and suitable for large-scale industrial production.

The application discloses a kind of compatible visible light and radar stealth material and preparation method thereof, belong to nano particulate stealth material and its preparation technical field.The application solves the problems such as thick coating, large specific gravity of traditional visible light-radar compatible stealth shell core coating material.The application prepares the stealth material of ferrite wrapping reduced graphene oxide by hydrothermal method, the stealth material has core-shell 3D porous structure, so that the overall quality of material is light, and better realizes the high absorption performance in the range of visible light and microwave, and, the color of the stealth material prepared by the application is black, further shows high absorption to visible light, specifically, in 350~750nm visible light range, the absorption rate is 0.92~0.96, and the reflection loss of 2~18GHz microwave band is about-40dB.Moreover, the preparation method provided by the application has the advantages of simplicity, abundant raw material resources, small environmental pollution and the like.

This invention belongs to the field of radar-infrared dual-band compatible materials, specifically relating to an MXene radar-infrared dual-band compatible flexible material and its preparation method. This invention uses patterned MXene material to form a periodic array structure. Utilizing its extremely high conductivity, it is equivalent to a metal in the radar band, thus constructing a novel frequency-selective surface to achieve high radar transmittance. Furthermore, MXene's intrinsic infrared high reflectivity, coupled with the array period and gap dimensions being much larger than the infrared wavelength, means that the proportion of the contact area between MXene and the incident infrared wave directly determines the overall average reflectivity. Therefore, by adjusting the specific dimensions of the MXene units in the array period, the performance of infrared-radar dual-band compatibility can be controlled. This invention achieves high transmittance in the microwave band while maintaining its low emission characteristics in the infrared band, thus providing a novel and customizable material solution for the radar-infrared compatible field.