22 results about "Atmospheric absorption" patented technology

The invention provides a geometric random channel modeling method for satellite-ocean communication, and the method comprises the steps: S1, building a satellite-ocean communication simulation scene, and setting scene layout parameters; s2, initializing a satellite transmitting end orbit parameter, a receiving end position and a sea wave fluctuation parameter; s3, calculating large-scale parameters with consistent space; s4, calculating path loss, shadow fading, atmospheric absorption loss, ionospheric scintillation loss and rainfall loss according to the set receiving and transmitting end position information; s5, calculating a small-scale parameter according to angle extension in the generated large-scale parameter, initializing the position of a scattering cluster on the sea surface and the surface of the ship body, generating time delay and power of the cluster, and generating a channel coefficient by combining the loss calculated in the step S4; s6, updating the large-scale parameters and the small-scale parameters according to the motion of the transmitting and receiving end and the birth and extinguishment process of the cluster, and generating a new channel coefficient; and S7, calculating channel statistical characteristics according to the obtained channel coefficients.

The invention discloses an offshore floating type low-altitude waveguide all-weather detection method and system, and relates to the technical field of marine environment monitoring and electronic information engineering.The method comprises the steps that the current weather condition is judged according to a rain intensity sensor, a miniature weather station, a visibility sensor and an infrared cloud measurement sensor; obtaining a temperature and humidity value range according to the current weather condition, and adding liquid water for correction according to the weather condition; a simulated brightness temperature is obtained according to a MonoRTM model by combining an air pressure profile constructed by sea surface air pressure and a pressure height formula; designing a multi-objective genetic inversion algorithm, constructing an objective function, and when the objective function obtains a minimum value, obtaining an inverted atmospheric parameter profile group; and according to the atmospheric parameter profile group, calculating an atmospheric refractive index profile, judging whether a low-altitude waveguide occurs or not, and uploading a result to a shore station data management center. According to the invention, the atmospheric absorption coefficient is corrected according to different weathers, and all-weather and high-precision monitoring of the low-altitude waveguide on the offshore floating platform is realized.

The invention provides a laser output adjustment method and device, computing equipment and a storage medium, and the method comprises the steps: collecting environment parameters, and calculating a scattering coefficient and an absorption coefficient based on the environment parameters; calculating the atmospheric transmittance based on the attenuation coefficient and the absorption coefficient; determining a recommended wavelength and a recommended line width based on the atmospheric transmittance; and adjusting the output of a target laser according to the recommended wavelength and the recommended line width. Atmospheric environmental parameters are monitored in real time, a correlation model with laser transmission efficiency is established, laser wavelength and line width are dynamically adjusted according to environmental changes, real-time atmospheric absorption peaks are avoided, and stable output of the laser is achieved.

The invention belongs to the technical field of atmospheric trace gas detection, and particularly relates to a laser heterodyne radiometer for locking local oscillator optical power based on an adjustable optical attenuator. Comprising a variable optical attenuator and an optical fiber beam splitter, and the optical fiber beam splitter transmits local oscillation light attenuated by the variable optical attenuator to a first photoelectric detector and a frequency calibration module and carries out beam combination and frequency beating on the local oscillation light and signal light; the output end of the first photoelectric detector serves as the input end of the PID controller, a control signal is calculated and sent to the variable optical attenuator, and the frequency calibration module and the signal processing module are jointly and sequentially connected with the acquisition card and the upper computer to output a measurement result. By combining the variable optical attenuator with digital PID feedback control, dynamic and closed-loop locking of local oscillator optical power is realized, an atmospheric absorption spectrum without a slope baseline can be obtained, and the accuracy of measuring the atmospheric gas concentration by the laser heterodyne radiometer is effectively improved.

Techniques for atmospheric absorption determination using embedded sensor data are provided. In one example, a system includes a housing. The system further includes a sensing device within the housing. The sensing device is configured to determine a humidity within the housing and a temperature within the housing. The system further includes a logic device. The logic device is configured to compensate the humidity and the temperature based on a location of the sensing device within the housing relative to heat sources within the housing. The logic device is further configured to determine a moisture value based on compensation of the humidity and the temperature. The logic device is further configured to determine an atmospheric absorption value based on the moisture value. Related devices and methods are also provided.

The invention discloses a universal water color satellite in-orbit radiometric calibration method, which belongs to the field of radiometric calibration and comprises a data analysis and quality control module, a radiometric calibration module, a calibration coefficient comprehensive analysis module and a working state recording module. According to the invention, the algorithm of the hyperspectral atmospheric absorption coefficient is optimized, and the compatibility of the on-orbit radiometric calibration algorithm to various types of water color satellite loads is realized.

The application discloses a kind of marine interface pollutant spatial distribution observation methods, it is related to marine environmental optical remote sensing monitoring technical field.The present application is according to the characteristics of sunlight spectrum sea surface reflection, selects solar sea surface glint as light source, improves the signal-to-noise ratio of spectral signal when collecting, simultaneously, the sunlight of specular reflection is no longer refracted into seawater, and will not change the atmospheric absorption structure of solar spectrum;When solar sea surface glint occurs reflection on sea surface, incident light is direct sunlight, and direct sunlight has a certain angle of incidence, so using solar sea surface glint as light source has clear observation geometry mode, can accurately calculate the optical path length of solar spectrum after absorbing near-sea surface atmospheric pollution gas, to accurately retrieve the concentration of relevant sea area near-sea surface atmospheric pollution gas, by setting equidistant observation angle in turn along the direction of solar sea surface glint, the distance resolution measurement of sea surface pollution gas can be realized.

This invention discloses a method and system for optimizing the spectral dispersion coefficient of a greenhouse gas spectrometer before launch. The method includes: acquiring the instrument's linear function, initial dispersion coefficient, and laboratory direct solar observation spectrum; simulating the atmospheric absorption spectrum based on a radiative transfer model and performing convolution processing using the instrument's linear function; screening for positionally robust reference absorption lines through environmental parameter sensitivity analysis; fitting the observed spectrum and simulated spectrum to find peaks, extracting the center wavelength, and calculating the wavelength shift; establishing a polynomial fitting relationship for the wavelength shift to obtain the wavelength shift fitting coefficient; performing a difference calculation between the initial dispersion coefficient and the wavelength shift fitting coefficient, keeping higher-order terms unchanged, and outputting the optimized dispersion coefficient. This invention can effectively improve the wavelength calibration accuracy of the spectrometer before launch.

The invention provides a gas remote sensing infrared characteristic calculation method and device. The technical problems that an existing high-temperature gas emission radiation long-distance transmission characteristic is huge in calculation amount and errors are not easy to overcome are solved through a broadband k distribution model based on atmospheric transmissivity weighting. The method comprises the following steps: establishing an atmospheric transmissivity weighted broadband k distribution model by using atmospheric transmissivity as an emission item influence factor of a gas internal spectral radiation transfer equation, and avoiding the reduction of calculation precision caused by uncorrelated k characteristics between a carrier hydrocarbon fuel gas wake flow absorption radiation spectrum and an atmospheric absorption radiation spectrum. A gas long-distance infrared characteristic calculation model which is small in calculation amount, high in calculation precision and good in compatibility is formed, and the requirements for precision and efficiency of numerical simulation of turbulent flow tail jet flow infrared remote sensing characteristics of a hydrocarbon fuel carrier and a complex structure exhaust system of the hydrocarbon fuel carrier can be met.

The invention relates to the field of abnormal sound detection, and discloses a household electrical appliance omnibearing abnormal sound detection system comprising a data acquisition module used for acquiring sound and vibration signals of a household electrical appliance through a multi-mode sensor; the environmental parameter acquisition module is used for acquiring environmental parameters including temperature, humidity, air pressure, PM2.5 concentration, wind speed and ozone concentration in real time; the signal processing module is used for processing the acquired signals by adopting a self-adaptive filtering algorithm and carrying out sound propagation attenuation compensation based on environmental parameters, and the sound propagation attenuation compensation adopts a polynomial model comprising an atmospheric absorption attenuation item, an aerosol attenuation item, a wind field attenuation correction item and a chemical attenuation item; the abnormal sound recognition module is used for carrying out abnormal sound feature extraction and classification recognition on the basis of the compensated signal; and the control execution module is used for controlling the automatic detection device to complete tool butt joint and detection operation. According to the technical scheme, all-directional abnormal sound detection of the household electrical appliance is realized.

This invention discloses a method and apparatus for evaluating on-board very long wave (VLW) spectral calibration based on a radiative transfer model, belonging to the field of remote sensing optics technology. This invention targets a wide-band VLW infrared hyperspectral sensor covering the wavelength range of 12-16 μm, analyzing the atmospheric absorption characteristics and sensor imaging spectral characteristics within this spectral range. The spectral calibration accuracy is evaluated through physical model simulation, including: simulation using the MODTRAN radiative transfer model; construction of a spectral drift model; solving for the center wavelength shift based on a spectral matching combined with an iterative optimization algorithm; and uncertainty analysis of the impact of factors such as the estimation error of the algorithm itself, sensor signal-to-noise ratio, inter-spectral response inconsistency, and atmospheric CO2 concentration on the estimation results. This invention is applied to evaluate the spectral calibration accuracy of on-orbit satellite data.

This invention discloses a method for solving the spectral emissivity of a wall surface based on a GRU network with an attention mechanism, comprising the following steps: dual-temperature calibration of an infrared radiometer using a reference blackbody; measuring the wall surface target using the calibrated infrared radiometer and calculating the target reference spectral radiance using the measurement results; constructing a GRU network model with an attention mechanism and training the model using the target reference spectral radiance data after removing atmospheric interference-related bands; using the trained network to predict and correct the mid-wave infrared and long-wave infrared regions, and solving the wall surface emissivity using the corrected spectral radiance. This method for solving the spectral emissivity of a wall surface, by constructing a recurrent neural network model, can correct the target reference spectral radiance, effectively eliminating the influence of atmospheric absorption on the emissivity solution and improving the accuracy of the wall surface spectral emissivity solution.

The invention discloses a stationary orbit hyper-spectrum detection system applied to high-aging dirt and carbon collaborative observation. According to the method, the problem of performance optimization caused by insufficient observation gas component elements, low spatial resolution, low observation timeliness and system integration of an existing remote sensor is solved. The invention provides a stationary orbit hyper-spectrum detection system for cooperative observation of pollution and carbon, which integrates pollution gas and greenhouse gas detection spectrum sections while exerting the advantage of high-time-efficiency observation of a stationary orbit, and realizes large dynamic range, ultra-high spectral resolution and high-sensitivity detection capability of near ultraviolet to short wave infrared atmospheric absorption spectrum.

The present invention discloses a universal on-orbit radiation calibration method for water color satellites, belonging to the field of radiation calibration. The method comprises a data analysis and quality control module, a radiation calibration module, a calibration coefficient comprehensive analysis module and a working status recording module. The present invention optimizes the algorithm of the hyperspectral atmospheric absorption coefficient and realizes the compatibility of the on-orbit radiation calibration algorithm with multiple types of water color satellite payloads.

The invention provides a high-reliability flame detection method and system for correcting infrared radiation atmospheric absorption influence, and the method comprises the steps: an infrared flame detection module is used for measuring an initial voltage value of a characteristic wavelength infrared radiation signal reaching a flame detector when a fire occurs; the atmosphere data measurement module is used for obtaining the concentration of infrared absorption gas on a radiation transmission path; the atmospheric transmission calculation module is used for calculating an atmospheric absorption coefficient at the working wavelength of the flame detector; and the infrared flame detector signal correction module is used for correcting the influence of the atmospheric absorption effect on the fire infrared radiation signal on the transmission path to obtain a corrected voltage value of the flame detector infrared radiation signal. According to the method, the attenuation of the target radiation intensity caused by the atmospheric absorption effect on an infrared radiation transmission geometric path is corrected, so that the flame detector obtains more accurate target infrared radiation characteristics, accurate basic data is provided for a flame discrimination algorithm, and the reliability of the infrared flame detector is improved.

The invention discloses a helicopter three-dimensional sound field prediction method and device, equipment, a medium and a product, and relates to the field of helicopter aeroacoustics, and the method comprises the steps: obtaining observation point information, and extracting flight parameters on a flight path of a helicopter; carrying out selection and attitude alignment on the flight parameters on the flight path of the helicopter and radiation balls in a helicopter sound radiation ball library to obtain the radiation balls corresponding to the flight path; the helicopter sound radiation ball library is constructed by using load information of a helicopter; taking a radiation ball corresponding to the flight path as a sound source for radiation, and calculating sound pressure levels of observation points under different propagation paths according to the observation point information based on a Gaussian beam theory of fluctuation acoustics; determining a total sound pressure level based on atmospheric sound absorption, geometric attenuation and reflection / transmission attenuation according to the sound pressure levels of the observation points in different propagation paths; and generating a helicopter three-dimensional sound field cloud picture by using the total sound pressure level. According to the method, the three-dimensional sound field of the helicopter under the complex terrain can be quickly predicted.

The present invention discloses an all-weather detection method and system for offshore floating low-altitude waveguides, which relates to the fields of marine environmental monitoring and electronic information engineering technology. The method comprises determining the current weather conditions based on a rainfall intensity sensor, a micro-meteorological station, a visibility sensor, and an infrared cloud sensor, and deriving a temperature and humidity range based on the current weather conditions, and adding a liquid water correction according to the weather conditions; combining the pressure profile constructed by the sea surface pressure and pressure height formula to obtain a simulated brightness temperature based on the MonoRTM model; designing a multi-objective genetic inversion algorithm to construct an objective function, and obtaining an inverted atmospheric parameter profile group when the objective function reaches a minimum value; calculating the atmospheric refractive index profile based on the atmospheric parameter profile group to determine whether a low-altitude waveguide has occurred, and uploading the result to a shore station data management center. The present invention corrects the atmospheric absorption coefficient for different weather conditions, achieving all-weather, high-precision monitoring of low-altitude waveguides on offshore floating platforms.

The application discloses an infrared spectrum atmospheric absorption interference correction method and system, and the method comprises the following steps: establishing a historical spectrum database; based on a to-be-corrected sample, screening from the historical spectrum database to obtain a near-neighbor reference base spectrum; setting a correction branch: a reference spectrum generation branch generates a reference spectrum of the to-be-corrected sample based on the to-be-corrected sample, the near-neighbor reference base spectrum and environmental and instrument parameters; a physical correction branch constructs a differential interference component based on a time sequence spectrum window, and carries out physical constraint correction by using a multi-spectrum robust estimation and an adaptive segmented scaling factor to obtain a physically corrected spectrum; a deep learning branch carries out deep residual learning on the to-be-corrected sample, the reference spectrum and the physically corrected spectrum to obtain a deep corrected spectrum; and according to the uncertainty or consistency of the correction branch, the corrected spectrum is adaptively fused to obtain a final corrected spectrum. The application realizes more fine and more robust correction of the infrared spectrum atmospheric absorption interference.

The invention belongs to the technical field of water vapor content observation by a microwave radiometer, and particularly relates to a method for improving integral water vapor content observation by the microwave radiometer. The problem that an existing radiometer is low in water vapor observation precision, and high-precision forecasting of cloudy and rainy weather is difficult is solved. The method comprises the following steps: S1, according to a troposphere atmosphere microwave remote sensing principle, atmospheric refraction error correction and a principle of observing water vapor content by using a microwave radiometer, determining different channels required by inversion of the water vapor content, namely a water vapor absorption channel and a liquid water channel; s2, an ITU-R P.676 proposal: an attenuation model of radio waves in the atmosphere is used for calculation, and the channel selected in the step S1 and the corresponding weight function, the total atmospheric attenuation, the ground atmospheric absorption coefficient and the atmospheric average temperature are calculated; and S3, substituting the calculated amount in the step S2 and the brightness temperature observed by the microwave radiometer into a calculation formula for observing the atmospheric moisture delay of the troposphere by the microwave radiometer, and calculating the atmospheric moisture delay of the troposphere.

This invention discloses a simplified calculation method for atmospheric absorption loss in a scenario of coexistence of ground-to-air interference, belonging to the field of satellite communication loss. Specifically, the method involves: First, constructing a visible region on the Earth's surface that constitutes an interference link to the satellite. This visible region is then divided into grids based on latitude and longitude, and the center point of each region is determined. The elevation angle of different regions relative to the satellite is determined based on the positional relationship between each center point and the satellite. Next, three different atmospheric layering models (medium, low, and high) are established based on latitude, covering radio wave signals in the 0-350 GHz frequency band. When a satellite signal passes through different atmospheric layering models, the actual path length through each atmospheric layer in each model is calculated. The absorption loss value of each atmospheric layer is also calculated. Finally, the atmospheric absorption loss values ​​within the 0-350 GHz frequency range for different latitudes and elevation angles are output. This invention improves atmospheric absorption loss efficiency and reduces resource consumption.

The present application relates to a kind of infrared absorption waveband atmospheric spectral transmittance measurement method, it is related to detection field, including the following steps, selecting the spectrometer capable of covering absorption waveband, and installing atmospheric absorption band filter on spectrometer;According to the minimum, maximum measurement value of spectrometer parameter selection corresponding attenuator;Spectrometer is directly aimed at solar spectrum data acquisition, reads the background average corresponding digital value measured by spectrometer;The bad point of calculated spectral data is rejected;Using the spectral calibration data in laboratory, the spectral data that has been rejected is quantitatively inversed, the radiation brightness of spectrometer is calculated;The absorption waveband spectral brightness of solar reaching ground is calculated;According to the radiation brightness of calculated spectrometer and the absorption waveband spectral brightness of solar reaching ground, atmospheric spectral transmittance is directly calculated, the present application has the advantages of expanding the measurement and inversion means of shortwave infrared absorption band atmospheric transmittance spectral research.

The invention provides an airport aircraft noise prediction method fusing an ellipsoid and a nonlinear function, relates to the technical field of environment monitoring and noise control, and solves the problem that the existing method is difficult to accurately describe the limitation of the propagation process of noise in a real dynamic environment. The method comprises the following steps: acquiring aircraft track data and ground monitoring point coordinates and noise data, and converting the data into a three-dimensional rectangular coordinate system; screening effective noise events based on the noise data, and performing association matching with the track data; based on the Morse theory of a motion sound source, constructing an ellipsoid model representing the sound level contour surface of the aircraft noise; based on noise attenuation characteristics and an ellipsoid model, combining Doppler effect and atmospheric absorption attenuation, and constructing a nonlinear function of noise sound level attenuation along with distance; and carrying out parameter optimization solution by utilizing a genetic algorithm to obtain optimal parameters of the model and outputting a noise prediction result. According to the method, an existing noise prediction technology system is perfected, and the aircraft noise influence in the peripheral area of the airport can be accurately evaluated.