CN115826088A - Laser heterodyne spectrum measurement method and system for vertical wind profile of middle and high-rise atmosphere - Google Patents
Laser heterodyne spectrum measurement method and system for vertical wind profile of middle and high-rise atmosphere Download PDFInfo
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Abstract
The invention relates to the technical field of atmospheric measurement optics, and discloses a laser heterodyne spectrum measurement method for vertical wind profiles of middle and high-rise atmosphere, which comprises the following steps: obtaining an atmospheric simulation absorption spectrum according to the established forward model; acquiring absorption spectrum data of high-quality atmospheric molecules by using a laser heterodyne method; establishing an inversion model of the atmospheric vertical wind profile according to the forward model and the absorption spectrum data; according to the atmospheric vertical wind profile obtained by minimizing the solution of the inversion model, the invention researches a forward model suitable for laser heterodyne detection and an atmospheric wind field inversion method by using a high-resolution CO2 heterodyne absorption spectrum of an atmospheric molecule which is actually measured, realizes inversion of the middle and upper atmospheric wind profile, not only can provide a necessary measurement means for the research of the telemetering and evolution rules of the atmospheric wind profile, but also can provide more comprehensive and accurate basic data for the atmospheric climate mode research, and promotes scientific cognition level of the influence of the atmospheric wind field on the global climate and the like.
Description
Technical Field
The invention relates to the technical field of atmospheric measurement optics, in particular to a laser heterodyne spectrum measurement method for vertical wind profiles of middle and high-rise atmosphere.
Background
The accurate detection of the wind profile of the middle and high-rise atmosphere (20-100 km) has great significance for understanding the formation mechanism, occurrence, development and movement evolution rule of weather phenomena, and has important effects on theoretical research of atmospheric science, performance evaluation of wind power plants, environmental monitoring, improvement of the prediction capability of global climate change and the accuracy of global numerical weather forecast (NWP). To scientifically recognize the influence of the high-rise atmospheric wind profile, the problem of how to obtain the atmospheric wind profile needs to be solved first.
Before the middle of the 20 th century, atmospheric wind profiles could only be obtained by simple direct detection means due to condition limitations, such as: cup anemometers, wing anemometers, catathermometers, and hot-bulb electric anemometers, wind vanes, etc., which are in direct contact with the atmosphere to acquire wind speed information. These devices have limited ability to detect large scale, large range wind profiles. In the middle and later period of the 20 th century, with the rapid development of laser technology, microwave technology and information processing technology, remote sensing detection is gradually developed into an important detection means in the field of earth atmosphere research. The method is different from the direct detection of the atmospheric wind profile, and the atmospheric wind profile remote sensing detection means that an atmospheric wind profile detector is not in direct contact with the measured atmosphere, the emitted radiation waves such as light waves, electromagnetic waves or sound waves are transmitted in the atmosphere, when the emitted radiation waves interact with substances carrying wind profile information, the frequency spectrum, the phase and the like of the radiation wave signals are changed along with the radiation waves, and finally the wind speed and wind direction information is obtained through the inversion of echo signals.
Atmospheric wind profile telemetry may be divided into active wind profile telemetry and passive wind profile telemetry. The active wind profile remote measuring technology mainly comprises a Doppler acoustic radar, a Doppler microwave radar and a Doppler laser radar. The Doppler sodar is mainly used for detecting the atmospheric wind profile of a boundary layer, and can measure the wind profile in a range from dozens of meters to one kilometer. However, the Doppler sodar has a short range and is not basically applied to remote sensing measurement at present. Doppler microwave radar has been widely used for telemetry of atmospheric wind profiles, where it interacts with large size particles in the atmosphere, such as clouds, rain, ice or inhomogeneities in the atmosphere, producing echoes, while interacting with small size atmospheric molecules and aerosols producing substantially no echo signals. Therefore, the Doppler microwave radar has strong remote sensing detection capability under the condition of cloud, rain and snow weather, and can form a detection blind area under the condition of uniform atmosphere in clear sky or low aerosol distribution density. In addition, the doppler microwave radar is not suitable for airborne and satellite-borne telemetry due to its large transceiver system.
The Doppler laser radar uses laser as a carrier signal, can interact with molecules and aerosol particles in the atmosphere to generate an echo signal, and is the best technical means for realizing global and all-weather wind profile remote measurement at present. Compared with a Doppler acoustic radar and a Doppler microwave radar, the Doppler laser radar has the advantages of high space-time resolution, high clear sky measurement precision, high response speed, large detection range (capable of extending to a low-heat layer), capability of simultaneously obtaining wind speed and wind direction distribution in a three-dimensional profile and the like. The Doppler laser radar wind measurement vertical effective area is from the ground to the height of 20km above sea level, and the vertical resolution is 1km. Infrared doppler lidar is commonly used widely for wind profile telemetry in a small area. However, the doppler lidar is based on active detection of a medium by a powerful light source (laser), and if a higher wind profile is obtained, the weight, the volume and the power consumption of the instrument are greatly increased.
The passive wind profile telemetry technology mainly comprises a Fabry-Perot interferometer (FPI), a Michelson interferometer and a Doppler asymmetric space heterodyne interferometer (DASH), and is deployed on the ground or a satellite-borne platform. The FPI wind profile detection technique acquires wind speed by accurately measuring the center and radius of interference fringes. In 1991, a High Resolution Doppler Imager (HRDI) carried by a URAS satellite realizes the detection of the wind profile of a stratosphere, a middle layer and a lower heat layer. Over the next few years, small ground FPIs were used in the united states and japan to study hot layer winds and temperatures. Wang et al also reported a ground FPI that combines measured data with an inversion algorithm to obtain a high altitude atmospheric profile using a band pass filter behind the etalon and galileo telescope systems.
Unlike the FPI principle, the michelson interferometer implements detection of the wind profile by measuring the phase change of the interference fringes. The wind imaging interferometer is a first satellite-borne instrument for realizing passive profile detection by utilizing the Michelson interferometer technology, and successfully detects the atmospheric profile within the height range of 80-300 km. The DASH technology is developed on the basis of a spatial heterodyne spectroscopy technology, and is a new technology developed for the specific application of middle and high atmospheric wind profile detection. In 2013, solheim and Shepherd, at York university, developed a SWIFT-DASH principle prototype for stratospheric wind profile and infrared ozone detection. Recently, shen et al analyzed the processing error of doppler asymmetric spatial heterodyne measurement data.
The atmospheric profile is influenced by various factors (such as atmospheric environment, longitude and latitude, temperature, pressure and the like), and the atmospheric profile changes greatly at different places and different times. To scientifically and accurately detect the middle and upper atmospheric wind profiles, the atmospheric wind profile information under various geographic environments needs to be acquired. This requires that the measurement instrument must have characteristics such as small, light in weight, the power consumption is little, with low costs, easy mobility on the basis of guaranteeing performance. The above-described atmospheric wind profile measurement instrument has been difficult to meet these requirements, and a new generation of atmospheric wind profile telemetry technology needs to be developed.
Disclosure of Invention
The invention aims to provide a laser heterodyne spectrum measurement method for vertical wind profile of middle and high-rise atmosphere, which solves the following technical problems:
how to provide a middle and high atmosphere vertical wind profile measuring method based on a laser heterodyne method.
The purpose of the invention can be realized by the following technical scheme:
the laser heterodyne spectral measurement method for the vertical wind profile of the middle and upper atmosphere comprises the following steps:
obtaining an atmospheric simulation absorption spectrum according to the established forward model;
acquiring absorption spectrum data of high-quality atmospheric molecules by using a laser heterodyne method;
establishing an inversion model of the atmospheric vertical wind profile according to the forward model and the absorption spectrum data;
obtaining an atmospheric vertical wind profile from minimizing a solution of the inverse model.
As a further scheme of the invention: the forward modeling method comprises the following steps:
layering the middle and high atmospheric layers by using an atmospheric layering method of FASCODE;
determining an atmospheric mode according to the actual atmospheric parameters;
calculating the molecular species absorbed by atmospheric molecules, and determining a solar transmission path;
calculating atmospheric molecular absorption and continuous absorption by using a line-by-line integration algorithm LBLRTM;
obtaining optical thicknesses corresponding to light rays with different wavelengths and atmospheric transmittance on a horizontal path and an inclined path;
calculating the total optical thickness of each layer by using the calculated optical thickness, and calculating to obtain parameters required by DISORT;
calling DISORT to calculate single scattering and multiple scattering to obtain a calculation result of atmospheric thermal radiation;
and acquiring scattered radiation on an inclined path according to the atmospheric thermal radiation.
As a further scheme of the invention: the acquisition mode of the absorption spectrum data comprises the following steps:
obtaining sunlight which passes through the atmosphere to the earth surface;
obtaining an atmospheric vertical wind profile by analyzing the atmospheric molecular absorption spectral line of the sunlight;
and selecting near-infrared laser with a preset central wavelength, and acquiring heterodyne spectrum signals to obtain the absorption spectrum data.
As a further scheme of the invention: the method for establishing the inversion model of the atmospheric vertical wind profile comprises the following steps:
performing spectral line type comparison analysis according to the absorption spectrum data and the atmospheric simulation absorption spectrum calculated by the forward model to obtain inversion of atmospheric vertical wind profile;
the inversion of the atmospheric vertical wind profile comprises:
consider the radiation transmission model and the doppler distortion of the absorption spectrum:
wherein ,
to be at wavelength
At the normalized optical depth of the vertical path,
for actually measuring the atmospheric transmittance, theta is the zenith angle of the sun, rho (z) is the density of an assumed CO2 molecule, U (z) is the vertical profile of an assumed atmospheric wind on the sight line, c is the light speed,
in order to absorb the center wavelength of the line,
for each molecule calculated according to the algorithm described above at wavelength
And a model absorption cross-section at height z;
the following function is constructed according to the Maximum Entropy Method (MEM):
wherein a function g (U) is introduced to provide a function omega ε Convexity of (U)G (U) is a smooth function of the form
ε =0.001, and satisfies the approximation property | Ω ε (U)-Ω(U)|<ε k, k is a constant;
in the tight album
Searching for a solution;
according to the generalized residual regularization method (GRM) is meant the introduction of a stable general function Ω (U, p) which is physically reasonable and follows special properties such as concavity and semicontinuousness to provide a convergent approach.
Constrained minimum stability function:
selecting a regularization standard, and performing iterative computation by using a Sequence Quadratic Programming (SQP) algorithm to obtain a solution of the minimized stability function and obtain an inversion model of the atmospheric vertical wind profile.
As a further scheme of the invention: laser heterodyne spectral measurement system of middle and high-rise atmosphere vertical wind profile includes:
the atmosphere simulation absorption spectrum acquisition module is used for acquiring an atmosphere simulation absorption spectrum according to the established forward model;
the high-quality absorption spectrum data acquisition module is used for acquiring absorption spectrum data of high-quality atmospheric molecules;
the construction module is used for establishing an inversion model of the atmospheric vertical wind profile according to the forward model and the absorption spectrum data;
and the processing module is used for obtaining the atmospheric vertical wind profile according to the solution of the minimized inversion model.
The invention has the beneficial effects that: the invention is based on a foundation near-infrared laser heterodyne experimental system established in a laboratory, a high-resolution CO2 heterodyne absorption spectrum of an atmospheric molecule which is actually measured, a forward model suitable for laser heterodyne detection and an atmospheric wind field inversion method are researched, and the inversion of middle and upper atmospheric wind profiles and the online measurement of the evolution characteristics of the middle and upper atmospheric wind profiles along with time and places are realized, so that a foundation is laid for the development of global and all-weather wind field remote measurement. The scheme adopted by the application can provide necessary measuring means for the research of the telemetering and evolution rules of the atmospheric wind profile, can also provide more comprehensive and accurate basic data for the research of atmospheric climate modes, and promotes scientific cognition level of the influence of atmospheric wind fields on global climate and the like.
Drawings
The invention will be further described with reference to the accompanying drawings.
FIG. 1 is a schematic diagram of a laser heterodyne spectroscopy measurement method of the present invention;
FIG. 2 is a schematic structural diagram of a high-quality absorption spectrum data acquisition module according to the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1, the present invention is a laser heterodyne spectroscopy method for measuring a vertical wind profile of a middle-high atmosphere, including:
obtaining an atmospheric simulation absorption spectrum according to the established forward model;
acquiring absorption spectrum data of high-quality atmospheric molecules by using a laser heterodyne method;
establishing an inversion model of the atmospheric vertical wind profile according to the forward model and the absorption spectrum data;
obtaining an atmospheric vertical wind profile from minimizing a solution of the inverse model.
In the invention, the laser heterodyne spectroscopy has the advantages that weak sunlight carrying atmospheric molecular absorption spectrum information after penetrating through the atmosphere is amplified by local laser with higher power, so that the atmospheric molecular absorption spectrum is acquired with high sensitivity and high resolution. Under ideal conditions, when the local oscillator laser power is high enough, the signal-to-noise ratio of the laser heterodyne system is close to the signal-to-noise ratio under the shot noise limit, and the spectral resolution of the system is determined by the electronic bandwidth of a subsequent radio frequency circuit and can reach several MHz. In addition, the optical path system of the laser heterodyne system is relatively simple and stable and can be realized in a small space.
Because the wind speed and the wind direction of wind fields at different heights are different and are influenced by Doppler broadening, the central frequency and the absorption line type of atmospheric molecule absorption spectral lines at different heights can be changed, and when the atmospheric wind field, the temperature, the pressure and other atmospheric parameters are known, the absorption line type of atmospheric molecules at a certain height can be determined. On the contrary, the CO2 absorption spectrum after the action of the middle-high atmospheric wind field is measured by the foundation laser heterodyne system, and the middle-high atmospheric wind profiles with different heights can be inverted based on the CO2 absorption spectrum line type.
As a further scheme of the invention: the forward modeling method comprises the following steps:
layering the middle and high atmospheric layers by using an atmospheric layering method of FASCODE;
determining an atmospheric mode according to the actual atmospheric parameters; or manually inputting atmospheric parameter profiles (detailed gas composition, prior estimation vertical concentration profile, pressure, temperature, wind field and the like) under real conditions;
then, calculating the molecular species absorbed by the atmospheric molecules by combining with the HITRAN2016 database of the latest version, and determining a solar transmission path;
calculating atmospheric molecular absorption and continuous absorption by using a line-by-line integration algorithm LBLRTM; selecting an aerosol calculation mode to perform aerosol attenuation calculation;
obtaining optical thicknesses corresponding to light rays with different wavelengths and atmospheric transmittance on a horizontal path and an inclined path;
calculating the total optical thickness of each layer by using the calculated optical thickness, and calculating to obtain parameters required by DISORT; calling DISORT to calculate single scattering and multiple scattering to obtain a calculation result of atmospheric thermal radiation; and acquiring scattered radiation on an inclined path according to the atmospheric thermal radiation. In the process of establishing a forward model by using a line-by-line integral algorithm (lblrtm), the inversion accuracy of the greenhouse gas vertical profile can be further improved by adding a DISORT scattering algorithm.
As a further scheme of the invention: the acquisition mode of the absorption spectrum data comprises the following steps:
obtaining sunlight which passes through the atmosphere to the earth surface;
obtaining an atmospheric vertical wind profile by analyzing the atmospheric molecular absorption spectral line of the sunlight;
and selecting near-infrared laser with a preset central wavelength, and acquiring heterodyne spectrum signals to obtain the absorption spectrum data.
As a further scheme of the invention: the method for establishing the atmospheric vertical wind profile inversion model comprises the following steps:
performing spectral line type comparison analysis according to the absorption spectrum data and the atmospheric simulation absorption spectrum calculated by the forward model to obtain inversion of atmospheric vertical wind profile;
the inversion of the atmospheric vertical wind profile comprises:
consider the radiation transmission model and the doppler distortion of the absorption spectrum:
wherein ,
to be at wavelength
At the normalized optical depth of the vertical path,
for actually measured atmospheric transmittance, theta is the solar zenith angle, rho (z) is the density of the assumed CO2 molecule, U(z) is the vertical profile of the assumed atmospheric wind on the line of sight, c is the speed of light,
in order to absorb the center wavelength of the line,
for each molecule calculated according to the algorithm described above at wavelength
And a model absorption cross-section at height z;
the following function is constructed according to the Maximum Entropy Method (MEM):
wherein a function g (U) is introduced to provide a function omega ε Convexity of (U), g (U) is a smooth function of the form
ε =0.001, and satisfies the approximation property | Ω ε (U)-Ω(U)|<ε k, k is a constant;
in the tight album
Searching for a solution;
according to the generalized residual regularization method (GRM) is meant the introduction of a stable general function Ω (U, p) which is physically reasonable and follows special properties such as concavity and semicontinuousness to provide a convergent approach.
Constrained minimum stability function:
selecting a regularization standard, and performing iterative computation by using a Sequence Quadratic Programming (SQP) algorithm to obtain a solution of the minimized stability function and obtain an inversion model of the atmospheric vertical wind profile. The method is characterized in that the high-quality spectral data of the whole layer of actual atmospheric molecules are obtained by combining a laser heterodyne method, and the precise measurement of the vertical wind profile of the middle-high atmosphere is realized by utilizing a generalized residual regularization criterion (GRM).
As shown in fig. 2, the laser heterodyne spectroscopy measurement system for the vertical wind profile of the middle and high-rise atmosphere includes:
the atmosphere simulation absorption spectrum acquisition module is used for acquiring an atmosphere simulation absorption spectrum according to the established forward model;
the high-quality absorption spectrum data acquisition module is used for acquiring absorption spectrum data of high-quality atmospheric molecules;
the construction module is used for establishing an inversion model of the atmospheric vertical wind profile according to the forward model and the absorption spectrum data;
and the processing module is used for obtaining the atmospheric vertical wind profile according to the solution of the minimized inversion model.
In the all-fiber portable near-infrared laser heterodyne wind profile detection system, the atmospheric wind field information is acquired by taking sunlight as passive telemetering of signal light, the atmospheric wind field information in a larger spatial scale range is rapidly acquired in real time in a small-volume and low-power consumption mode, the defects of large volume and difficulty in moving of the conventional middle-high atmospheric wind field detection technology equipment are overcome, and the practicability and the convenience are higher.
The detection of atmospheric components by the laser heterodyne detection method is a passive detection method using sunlight as signal light. Sunlight penetrates through the atmosphere to reach the earth surface, absorption information of various molecules in the atmosphere is carried, and the atmospheric vertical wind profile can be obtained through Doppler analysis of the high-resolution atmospheric molecule absorption spectrum line type. The near-infrared laser heterodyne system with the central wavelength of 1.605mm is adopted to detect the atmospheric CO2 molecules, and the CO2 molecules in the wave band are less interfered by the absorption of other atmospheric molecules, so that more accurate CO2 molecule absorption line type information can be obtained.
The schematic diagram of the designed experimental system is shown in fig. 2. The sun tracker with high pointing accuracy is used for tracking the position of the sun in real time, and the optical fiber coupling collimating lens arranged on the sun tracker is used for collecting sunlight and collecting the sunlight into a longer single-mode optical fiber. The sunlight emitted from the optical fiber is subjected to intensity modulation through the 1 x 2 optical fiber coupling optical switch, and a part of the sunlight emitted from the optical switch directly enters the optical power detector for calibrating the change of the sunlight power. Laser beams emitted by a local oscillator laser are divided into two beams through an optical fiber beam splitter, wherein a part of the laser beams are combined with sunlight modulated by the intensity of an optical switch through an optical fiber coupler, optical mixing is carried out on a photosensitive surface of a frequency mixer, direct current signals and difference frequency signals generated after the frequency mixing pass through a radio frequency filter and a radio frequency amplifier, power detection is carried out through a radio frequency power detector, finally the direct current signals and the difference frequency signals are sent to a phase-locked amplifier to be combined with synchronous reference signals output by the optical switch to carry out correlation demodulation, final heterodyne signals are output, and a function generator is used for generating sawtooth wave signals to drive the laser to carry out wavelength scanning, so that complete heterodyne spectrum signals are obtained; and the other part of laser beams split by the optical fiber beam splitter passes through the optical collimator, then passes through the optical etalon and the absorption cell, and then enters the photoelectric detector for frequency calibration. The data acquisition card acquires the signals and displays the signals on a notebook computer through Labview analog simulation software. Wherein, when the system is optimized, the blackbody light path is used to replace the sunlight light path.
While one embodiment of the present invention has been described in detail, the description is only a preferred embodiment of the present invention and should not be taken as limiting the scope of the invention. All equivalent changes and modifications made within the scope of the present invention shall fall within the scope of the present invention.
Claims (5)
1. The laser heterodyne spectrum measurement method for the vertical wind profile of the middle-high atmosphere is characterized by comprising the following steps of:
obtaining an atmospheric simulation absorption spectrum according to the established forward model;
acquiring absorption spectrum data of high-quality atmospheric molecules by using a laser heterodyne technology;
establishing an inversion model of the atmospheric vertical wind profile according to the forward model and the absorption spectrum data;
obtaining an atmospheric vertical wind profile from minimizing a solution of the inverse model.
2. The laser heterodyne spectroscopy measurement method for the vertical wind profile of the middle-high atmosphere according to claim 1, wherein the forward model establishing method comprises:
layering the middle and high atmospheric layers by using an atmospheric layering method of FASCODE;
determining an atmospheric mode according to the actual atmospheric parameters;
calculating the molecular species absorbed by atmospheric molecules, and determining a solar transmission path;
calculating atmospheric molecular absorption and continuous absorption by using a line-by-line integration algorithm LBLRTM;
obtaining optical thicknesses corresponding to different wave numbers and atmospheric transmissivity on a horizontal path and an inclined path;
calculating the total optical thickness of each layer by using the calculated optical thickness, and calculating to obtain parameters required by DISORT;
calling DISORT to calculate single scattering and multiple scattering to obtain a calculation result of atmospheric thermal radiation;
and acquiring scattered radiation on an inclined path according to the atmospheric thermal radiation.
3. The laser heterodyne spectrometry method for measuring the vertical wind profile of the middle-high atmosphere as claimed in claim 1, wherein the acquisition mode of the absorption spectrum data comprises:
obtaining sunlight which passes through the atmosphere to the earth surface;
obtaining an atmospheric vertical wind profile by analyzing the atmospheric molecular absorption spectral line profile of the sunlight:
and selecting near-infrared laser with a preset central wavelength, and acquiring heterodyne spectrum signals to obtain the absorption spectrum data.
4. The laser heterodyne spectroscopy measurement method for the vertical wind profile of the middle and upper atmosphere according to claim 1, wherein the method for establishing the inversion model of the vertical wind profile of the atmosphere comprises:
performing spectral line type comparison analysis according to the absorption spectrum data and the atmospheric simulation absorption spectrum calculated by the forward model to obtain inversion of atmospheric vertical wind profile;
the inversion of the atmospheric vertical wind profile comprises:
consider the radiation transmission model and the doppler distortion of the absorption spectrum:
wherein H is the height of the middle and upper atmospheric layers,
to be at wavelength
At the normalized optical depth of the vertical path,
to measure the atmospheric transmittance, θ is the zenith angle of the sun, ρ (z) is the density of the assumed CO2 molecule, U (z) is the vertical profile of the assumed atmospheric wind on the sight line, c is the speed of light,
in order to absorb the center wavelength of the line,
for each molecule calculated according to the algorithm described above at wavelength
And a model absorption cross-section at height z;
the following function is constructed according to the maximum entropy method:
wherein a function g (U) is introduced to provide a function omega ε Convexity of (U), g (U) is a smooth function of the form
And satisfies the approximate property | Ω ε (U) -omega (U) | < epsilon k, k being a constant;
in the tight album
Searching for a solution;
regularization methods according to the generalized residual mean to introduce a stable harmonic function Ω (U, p) that is physically reasonable and follows special properties such as concavity and semicontinuousness to provide a convergent approach.
Constrained minimum stability function:
and selecting a regularization standard, and performing iterative computation by using a sequential quadratic programming algorithm to obtain a solution of the minimized stability function and obtain an inversion model of the atmospheric vertical wind profile.
5. Laser heterodyne spectral measurement system of perpendicular wind profile of middle and high-rise atmosphere, its characterized in that includes:
the atmosphere simulation absorption spectrum acquisition module is used for acquiring an atmosphere simulation absorption spectrum according to the established forward model;
the high-quality absorption spectrum data acquisition module is used for acquiring absorption spectrum data of high-quality atmospheric molecules;
the construction module is used for establishing an inversion model of the atmospheric vertical wind profile according to the forward model and the absorption spectrum data;
and the processing module is used for obtaining the atmospheric vertical wind profile according to the solution of the minimized inversion model.
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| CN117113648A (en) * | 2023-08-03 | 2023-11-24 | 西安中科天塔科技股份有限公司 | Method and system for measuring concentration of carbon dioxide column |
| CN118549382A (en) * | 2024-05-20 | 2024-08-27 | 合肥大学 | Single-sideband spectrum measurement method based on laser heterodyne spectrometer |
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| CN118549382A (en) * | 2024-05-20 | 2024-08-27 | 合肥大学 | Single-sideband spectrum measurement method based on laser heterodyne spectrometer |
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