Satellite-borne hyperspectral detection laser radar atmospheric particle inversion method

Abstract

The invention discloses a spaceborne hyperspectral detection laser radar atmospheric particle inversion method. The method comprises the following steps of solving a laser ranging value and an altitude corresponding to a spaceborne hyperspectral resolution laser radar (HSRL) echo signal sampling point; reducing the noise of the echo signal by using a noise removal method; carrying out distance and system constant correction on the de-noised signal; a forecasting model is used for reanalyzing the data set, and S6, a molecular scattering signal transmittance lookup table is established through an atmosphere model and an iodine molecule hyperspectral filter absorption spectrum; calculating back scattering coefficients and scattering ratios of the cloud and the aerosol; performing hierarchical identification by using a scattering ratio and voltage signal-to-noise ratio threshold method; determining an effective inversion region through hierarchical region processing; calculating an initial extinction coefficient to a radar ratio; and performing Gaussian smoothing filtering on the radar ratio to obtain a final radar ratio, and calculating a final extinction coefficient profile. The method is characterized in that cloud and aerosol level identification is carried out on spaceborne HSRL echo signals, a molecular transmittance lookup table of a hyperspectral channel is established, and cloud and aerosol optical parameters are accurately and efficiently solved.

Description

Technical Field

[0001] The invention belongs to the field of atmospheric environment satellite optical remote sensing, and specifically is a method for inverting atmospheric particles (clouds and aerosols) by using a satellite-borne HSRL (High-Spectral-Resolution Lidar). Background Art

[0002] Aerosol refers to a multiphase system composed of the atmosphere and solid and liquid particles suspended in it, with particle diameters ranging from 0.001 to 100 microns; clouds are visible aggregates floating in the air, composed of small water droplets liquefied by water vapor in the atmosphere or small ice crystals condensed when cooled. Clouds and aerosols play an important role in the earth's atmospheric environment and in regulating the earth's climate. Therefore, obtaining high-temporal and spatial resolution vertical profiles and optical properties of global atmospheric clouds and aerosols is of great significance for weather forecasting, global radiation balance, and air quality monitoring.

[0003] As an active remote sensing detection tool, lidar is widely used in cloud and aerosol profile detection due to its advantages of high temporal and spatial resolution and continuous detection during the day and night. Among atmospheric lidars, high spectral resolution lidars do not need to assume lidar ratios, can directly invert cloud and aerosol optical parameters, and significantly improve inversion accuracy, becoming one of the important technologies in the field of atmospheric detection. However, neither ground-based nor airborne hyperspectral lidars can achieve all-day, real-time global cloud and aerosol measurements.

[0004] Spaceborne HSRL separates the Mie scattering of aerosols and the Rayleigh scattering of molecules in the echo signal based on the iodine molecular filter hyperspectral channel, so that the optical parameters of clouds and aerosols can be directly inverted without assuming the lidar ratio. Spaceborne HSRL has the following advantages:

[0005] (1) It can realize the measurement of clouds and aerosols on a global scale all day long.

[0006] (2) The laser radar detection signal can be used to directly invert the cloud and aerosol optical parameter profiles, greatly improving the inversion accuracy.

[0007] Patent document CN114296103A discloses a method for inverting the extinction coefficient of an airborne high spectral resolution lidar. However, this patented technology solves the processing and inversion of high spectral resolution lidar data of an airborne platform. Its inversion height range is much lower than that of a satellite platform and is not suitable for the inversion of satellite platform data. Summary of the invention

[0008] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a method for inverting atmospheric particles of a spaceborne hyperspectral detection laser radar to obtain high-precision global cloud and aerosol optical parameters. The laser ranging value and altitude corresponding to the sampling point of the spaceborne hyperspectral resolution laser radar echo signal are solved; a variety of denoising methods are used to reduce the noise of the HSRL echo signal; the HSRL detection signal is corrected for distance and system constants; the molecular transmittance lookup table of the hyperspectral detection channel is established using the temperature and pressure profiles of the numerical weather forecast model reanalysis data set, the S6 atmospheric model and the iodine molecular filter absorption spectrum, and the aerosol transmittance and atmospheric molecular parameters of the hyperspectral detection channel are calculated; the cloud and aerosol backscattering coefficients and scattering ratios are calculated based on the attenuated backscattering coefficients; the echo voltage signal-to-noise ratio is calculated; the scattering ratio and voltage signal-to-noise ratio threshold method is used for hierarchical identification; the effective data inversion area is determined through hierarchical regional processing; the cloud and aerosol optical thickness, extinction coefficient and radar ratio are preliminarily inverted; the final radar ratio is obtained by Gaussian smoothing filtering of the preliminarily inverted radar ratio, and the final extinction coefficient is calculated from this.

[0009] The technical solution of the present invention is as follows:

[0010] A method for inverting atmospheric particles using a spaceborne hyperspectral detection lidar is characterized in that it comprises the following steps:

[0011] (1) The satellite-borne lidar system mainly consists of two parts: the transmitter and the receiver. The transmitter emits a pulsed laser with a wavelength of 532nm, which acts on atmospheric molecules, clouds and aerosols and causes transmission, absorption and scattering. At the receiving end, the lidar telescope receives the backscattered signals of atmospheric molecules, clouds and aerosols, and obtains polarization signals, parallel channel signals and pure molecular scattering signals through hyperspectral detection.

[0012] (2) Solve the laser ranging value and altitude corresponding to each sampling point in the echo signal.

[0013] (3) The echo voltage signal is denoised and smoothed using contour superposition, sliding average and wavelet denoising methods.

[0014] (4) Based on step (3), the atmospheric echo signal detected by the satellite-borne laser radar is corrected for distance and system constants to obtain a corrected attenuated backscatter signal.

[0015] (5) Based on the temperature and pressure profiles given by the reanalysis meteorological data set of the numerical weather forecast model, the S6 atmospheric model, and the absorption spectrum of the iodine molecular filter, a molecular transmittance lookup table for the hyperspectral channel is established, and the aerosol transmittance and atmospheric molecular parameters of the hyperspectral channel are solved.

[0016] (6) The aerosol backscattering coefficient is preliminarily inverted using the attenuated backscattering signal, molecular transmittance lookup table, aerosol transmittance and atmospheric molecular parameters, and the atmospheric scattering ratio is calculated.

[0017] (7) The voltage signal-to-noise ratio is calculated using the echo voltage signal and the background noise of the high-altitude background atmosphere.

[0018] (8) Using the atmospheric scattering ratio and voltage signal-to-noise ratio, the cloud and aerosol layer recognition thresholds are set to identify the cloud and aerosol layers, and the surface is screened out from the existing layers according to the elevation of the radar pointing point;

[0019] (9) The cloud and aerosol layers are merged as the hierarchical region, and the surface and clean atmosphere are merged as the non-hierarchical region. Only the data in the hierarchical region are retained as valid data to participate in the subsequent inversion of cloud and aerosol optical parameters.

[0020] (10) Preliminary inversion of cloud and aerosol optical thickness (atmospheric optical thickness), extinction coefficient, and radar-specific optical parameters is performed using the attenuated backscatter signal, molecular transmittance lookup table, aerosol transmittance, atmospheric molecular parameters, and layer identification results.

[0021] (11) Taking advantage of the small dynamic range of the lidar ratio, the radar ratio is subjected to Gaussian smoothing filtering to obtain the final radar ratio inversion result. The optimized cloud and aerosol extinction coefficient inversion result is obtained by combining the relationship between the extinction coefficient and the radar ratio.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] (1) The present invention uses the reanalysis data set of the numerical weather forecast model and the absorption spectrum of the iodine molecular filter to establish a molecular transmittance lookup table for hyperspectral channels at different temperatures and pressures, thereby improving the efficiency of processing satellite remote sensing data. Based on the hyperspectral detection data of satellite-borne laser radar, the present invention proposes a new layer recognition method, which realizes the effective recognition of cloud and aerosol layers in the atmosphere and improves the inversion accuracy of hyperspectral detection data. By using the collected laser radar data and the processing method based on the hyperspectral detection data of the satellite-borne laser radar, the data processing and optical parameter inversion of the high-spectral resolution laser radar of the satellite-borne platform are realized.

[0024] (2) Combining laser radar technology with satellite platforms, it has achieved long-distance, high-precision detection of atmospheric molecules, clouds and aerosols. The polarization signal, parallel channel signal and pure molecular scattering signal in the echo signal are obtained through hyperspectral detection technology, which improves the detection capability of atmospheric components. The laser ranging formula and satellite position coordinates, the longitude and latitude corresponding to the laser radar pointing point, the elevation and the delay time of the echo acquisition segment are used to accurately calculate the laser ranging value and altitude corresponding to the echo signal sampling point, which improves the accuracy of ranging and altitude calculation.

[0025] (3) By setting the scattering ratio threshold and the voltage signal-to-noise ratio threshold, accurate identification of cloud and aerosol layers is achieved, and the layer area is used as effective data for subsequent aerosol optical parameter inversion. This innovation in layer identification and processing methods improves the accuracy and reliability of the inversion results. Using the echo voltage signal received by the satellite for quality control and layer identification, it is possible to invert the cloud and aerosol optical parameters within the airborne detection range, as well as the optical parameters in a higher range. At the same time, due to the satellite's real-time global monitoring all day long, the number of signals received is extremely large. Starting from the data inversion efficiency, the present invention proposes a method for establishing a hyperspectral channel molecular transmittance lookup table, which greatly improves the efficiency of batch processing of satellite remote sensing data.

[0026] (4) Compared with CN114296103A, the present invention uses the echo voltage signal received by the satellite for quality control and layer identification, which can not only invert the optical parameters of clouds and aerosols within the airborne detection range, but also invert the optical parameters of a higher range. At the same time, due to the satellite's real-time global monitoring all day, the number of signals received is extremely large. Starting from the data inversion efficiency, the present invention proposes a method for establishing a molecular transmittance lookup table for a hyperspectral channel, which greatly improves the efficiency of satellite remote sensing data batch processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a specific schematic diagram of the present invention.

[0028] Figure 2 Schematic diagram of laser radar pointing point calculation. DETAILED DESCRIPTION

[0029] In order to more clearly illustrate the processing method based on satellite-borne laser radar hyperspectral detection data, the present invention is further described below with reference to examples and drawings. Figure 1 A specific flow chart of the algorithm of the present invention is given.

[0030] The specific embodiments of the present invention are as follows:

[0031] (1) The satellite-borne lidar system mainly consists of two parts: the transmitter and the receiver. The transmitter emits a pulsed laser with a wavelength of 532nm, which acts on atmospheric molecules, clouds and aerosols and causes transmission, absorption and scattering. At the receiving end, the lidar telescope receives the backscattered signals of atmospheric molecules, clouds and aerosols, and obtains the echo signal (including polarization signal, parallel channel signal and pure molecular scattering signal) through hyperspectral detection.

[0032] (2) Solution of laser ranging value and altitude corresponding to echo signal sampling point

[0033] To obtain the laser ranging value and altitude corresponding to the sampling point of the echo signal (the general term for the signals received by the three channels), the satellite position coordinates, the longitude and latitude corresponding to the laser radar pointing point, the elevation corresponding to the pointing point, and the delay time of the echo acquisition segment are used. The laser ranging formula is as follows:

[0034]

[0035] Where T d is the delay time of the echo acquisition segment, T a It is a fixed time difference between the trigger pulse of the data acquisition and the emission of the laser pulse, N is the number of position points in the echo signal acquisition segment, DA is the sampling frequency of the echo signal, and C is the speed of light in vacuum.

[0036] After obtaining the ranging value, it is necessary to use the ranging information to further solve the altitude of each sampling point of the echo signal, as shown in Figure (2), r is the distance from the satellite platform to the sampling point, h is the altitude corresponding to each sampling point, l is the distance from the satellite platform to the ground pointing point, d is the elevation of the pointing point, and the calculation formula is as follows:

[0037] According to the longitude and latitude, calculate the radius R of the earth, and according to the radius of the earth, longitude and latitude and elevation, calculate the X, Y, and Z coordinates of the laser pointing point.

[0038]

[0039] X=(r+d)·cosφ·cosλ (9)

[0040] Y=(r+d)·cosφ·sinλ (10)

[0041] Z=(r(1-f) 2 +d)·sinφ (11)

[0042] Where φ is latitude, λ is longitude, A is the semi-major axis of the Earth 6378137m, f is the polar oblateness 1 / 298.257223565, and d is the altitude of WGS-84 at that longitude and latitude.

[0043] According to the X, Y, Z coordinates of the laser pointing point and the X 星 , Y 星 , Z 星 Coordinates, calculate the distance l between the satellite platform and the ground pointing point

[0044]

[0045] Where X 星 , Y 星 , Z 星 The X, Y, and Z coordinates of the satellite in the WGS-84 coordinate system.

[0046] Then further calculate the altitude h of each sampling point

[0047] h=l+dr (13)

[0048] Where r is the distance from the satellite to the sampling point, that is, the laser ranging value.

[0049] Using the calculated altitude of the acquisition point, the echo data acquisition point is matched to an altitude grid ranging from 42 km to -0.96 km, and the vertical resolution of the grid is 24 m.

[0050] (3) Echo voltage signal denoising

[0051] In this embodiment, the horizontal resolution of the signal is 337.5m, and the vertical resolution is 24m. Considering the reduction of signal noise while ensuring a high resolution of the inversion result, 59 echo voltage signals are stacked and averaged in the horizontal direction, and 2 echo voltage signals are stacked and averaged in the vertical direction. First, the signal (the echo voltage signal after stacking and averaging) is filtered using the sliding average method, and the sliding window lengths of the parallel, polarization and hyperspectral channels are 10, 10 and 15 respectively. Then, the signal is denoised using the wavelet denoising algorithm and the appropriate denoising order, and the denoising orders of the parallel, polarization and hyperspectral channels are 3, 3 and 6 respectively. The use of the above denoising algorithm makes the horizontal resolution of the subsequent aerosol optical parameter inversion results become 20km, and the vertical resolution becomes 48m.

[0052] (4) Correct the distance and system constants of the echo signal

[0053] On the basis of step (3), the echo signal detected by the onboard HSRL is corrected for distance and system constants. The attenuated backscatter coefficients of the three channels are obtained using the channel system constants calibrated on-orbit and the response parameters and gain coefficients of the detector calibrated on the ground. The formula is as follows:

[0054]

[0055] Where r is the distance from the satellite platform to the atmospheric detection area, is the attenuation backscattering coefficient of the corresponding channel, and the echo optical power It represents the denoised voltage amplitude of the echo signal incident on the corresponding channel, i=C, M represents the reference channel and the hyperspectral molecular channel, j=⊥, ∥ represents the polarization and parallel components, and k=1, 2, 3 represents the polarization channel, the reference parallel channel and the hyperspectral channel. A1, A2 and A3 are the on-orbit calibration system constants of the 532nm polarization channel, the reference parallel channel and the hyperspectral channel, respectively. R1, R2 and R3 are the detector response parameters of the 532nm polarization channel, the reference parallel channel and the hyperspectral channel measured on the ground, respectively. G1, G2 and G3 are the detector amplification gain coefficients of the 532nm polarization channel, the reference parallel channel and the hyperspectral channel measured on the ground, respectively.

[0056] (5) Establishment of molecular transmittance lookup table and solution of aerosol transmittance and atmospheric molecular parameters

[0057] In order to improve the efficiency of HSRL data processing, a molecular transmittance lookup table for the hyperspectral channel was established. The molecular transmittance lookup table was established by using the meteorological profile data in the numerical weather forecast model reanalysis data set. The Rayleigh scattering spectrum of atmospheric molecules was calculated through the temperature profile, pressure profile and S6 atmospheric model, and then the molecular transmittance data was obtained after convolution calculation with the absorption spectrum of the iodine molecular filter measured in the laboratory. The transmittance of aerosol can be approximately equal to the result of the convolution of the Gaussian linear spectrum of the laser and the absorption spectrum of the iodine molecular filter. At the same time, the temperature profile and pressure profile of the numerical weather forecast model reanalysis data set are combined with the Rayleigh scattering theory to solve the backscattering coefficient, extinction coefficient and depolarization ratio of atmospheric molecules.

[0058] (6) Calculation of backscatter coefficient and scattering ratio

[0059] The aerosol backscattering coefficient β is calculated using the attenuated backscattering coefficients of the three channels after denoising, the molecular transmittance lookup table of the hyperspectral channel, the aerosol transmittance, the atmospheric molecular backscattering coefficient and the atmospheric molecular depolarization ratio. a (r), the formula is as follows:

[0060]

[0061] Among them, T m (r) and T a(r) respectively represent the transmittance of the molecular Rayleigh scattering echo signal and the aerosol Mie scattering echo signal after passing through the iodine molecular filter of the hyperspectral channel at the detection distance r; δ(r) is the total depolarization ratio of the atmosphere, which can be expressed as the ratio of the attenuated backscattering coefficient of the polarized channel to the attenuated backscattering coefficient of the reference parallel channel; K(r) is the ratio of the attenuated backscattering coefficient of the reference parallel channel to the hyperspectral channel; δ m is the depolarization ratio of atmospheric molecules; β m (r) and β a (r) are the backscattering coefficients of atmospheric molecules and aerosols, respectively.

[0062] Using the calculated aerosol backscattering coefficient and the backscattering coefficient of atmospheric molecules, the scattering ratio is calculated using the following formula:

[0063] (7) Calculate the echo voltage signal-to-noise ratio

[0064] The voltage signal-to-noise ratio of the polarization channel and the reference parallel channel is calculated by using the original voltage echo signals of the polarization channel and the reference parallel channel of the spaceborne lidar and the background noise of the corresponding high-altitude clean background atmosphere area. The formula is as follows:

[0065]

[0066] Among them, U i (r) represents the original voltage signal of the receiving channel, Represents the average value of the background noise in the high-altitude clean background atmospheric area of ​​the receiving channel (the first 100-500 voltage sampling points), i=⊥, ∥ represents the polarization and parallel components. At the same time, considering the resolution of the inversion results of aerosol optical parameters, the voltage signal noise ratio profile is stacked and averaged 59 times in the horizontal direction and 2 times in the vertical direction, the horizontal resolution becomes 20km, and the vertical resolution becomes 48m.

[0067] (8) Cloud and aerosol layer identification

[0068] Using the calculated atmospheric scattering ratio, an appropriate scattering ratio threshold is set. Positions exceeding the cloud and aerosol scattering ratio threshold are preliminarily determined to be clouds and aerosols, and positions below the threshold are preliminarily determined to be clean atmosphere without layers. In the preliminary layer recognition results, when the layer elevation is lower than the elevation of the laser radar pointing point, the layer is marked as the surface;

[0069] Then, using the calculated voltage signal-to-noise ratio, different voltage signal-to-noise ratio thresholds are set according to different daytime and nighttime scenes to optimize the initial hierarchical identification results and obtain more accurate cloud and aerosol hierarchical identification results. In the initial hierarchical identification results, locations greater than the voltage signal-to-noise ratio threshold are ultimately determined as clouds and aerosols, otherwise they are classified as clean atmosphere.

[0070] (9) Regional processing of cloud and aerosol layers

[0071] Using the results of cloud and aerosol layer identification, the cloud and aerosol layers are merged as the hierarchical area, and the surface and clean atmosphere are merged as the non-hierarchical area. Only the data in the hierarchical area are retained and used as valid data for the subsequent inversion of aerosol optical parameters.

[0072] (10) Preliminary inversion of cloud and aerosol optical parameters

[0073] Using the calculated attenuated backscattering signal, molecular transmittance lookup table, aerosol transmittance, atmospheric molecular parameters and layer identification results, the optical thickness of clouds and aerosols in the layer area (atmospheric optical thickness) is calculated using the following formula:

[0074]

[0075] Where, τ(r) is the atmospheric optical thickness; α a (r) and α m (r) are the extinction coefficients of aerosols and atmospheric molecules, respectively.

[0076] The sliding average method is used to smooth and denoise the optical thickness to improve the inversion accuracy of the extinction coefficient. The aerosol extinction coefficient α is calculated using the following formula: a (r) and radar ratio S a Calculation of (r):

[0077]

[0078] Among them, S a (r) is the lidar ratio of clouds to aerosols.

[0079] (11) Inversion results of cloud and aerosol optical parameters

[0080] Using the preliminary inversion of the cloud and aerosol lidar ratio, the radar ratio is Gaussian smoothed to obtain the final radar ratio inversion result, and the optimized cloud and aerosol extinction coefficient inversion result is obtained by combining the relationship between the extinction coefficient and the radar ratio.

[0081] The present invention utilizes the echo voltage signal received by the satellite for quality control and layer recognition, which can not only effectively identify and invert clouds and aerosols within the airborne altitude range, but can also be applied to the inversion of clouds and aerosols in a higher range; by establishing a molecular transmittance lookup table for a hyperspectral channel, the inversion efficiency of satellite remote sensing data can be greatly improved.

Claims

1. A method for inverting atmospheric particles using spaceborne hyperspectral detection lidar. It is characterized in that include: S1. Use the spaceborne hyperspectral detection lidar system to detect and obtain the backscattering signals of atmospheric molecules, clouds and aerosols. Through hyperspectral detection, the echo signals containing polarization signals, parallel channel signals and pure molecular scattering signals are obtained; S2. Calculate the laser ranging value and altitude corresponding to each sampling point in the echo signal; S3. Performing denoising and smoothing processing on the echo signal to obtain a denoised signal; S4. Performing distance and system constant correction on the denoised echo signal to obtain a corrected attenuated backscatter signal; S5. Establish a molecular transmittance lookup table for the hyperspectral channel and calculate the aerosol transmittance and atmospheric molecular parameters of the hyperspectral channel; S6. Using the attenuated backscattering signal, the molecular transmittance lookup table, the aerosol transmittance and the atmospheric molecular parameters, preliminarily invert the aerosol backscattering coefficient and calculate the atmospheric scattering ratio; S7. Calculate the voltage signal-to-noise ratio based on the original voltage echo signal and the background noise of the corresponding high-altitude clean atmosphere area, and perform superposition and averaging processing; S8. Using the atmospheric scattering ratio and the voltage signal-to-noise ratio, set the threshold for cloud and aerosol layer recognition, perform cloud and aerosol layer recognition, and screen out the surface in the existing layers according to the elevation of the radar pointing point; S9. Merge the cloud and aerosol layers as the hierarchical region, and the surface and clean atmosphere as the non-hierarchical region. Only the data in the hierarchical region are retained as valid data to participate in the subsequent inversion of cloud and aerosol optical parameters. S10. Perform preliminary inversion of atmospheric optical thickness, extinction coefficient and radar specific optical parameters using attenuated backscatter signals, molecular transmittance lookup table, aerosol transmittance, atmospheric molecular parameters and layer identification results; S11. Taking advantage of the small dynamic range of the lidar ratio, the radar ratio is Gaussian smoothed and filtered to obtain the final radar ratio inversion result. The optimized cloud and aerosol extinction coefficient inversion result is obtained by combining the relationship between the extinction coefficient and the radar ratio.

2. The method for inverting atmospheric particles using a spaceborne hyperspectral detection lidar according to claim 1, It is characterized in that The step S2. solves the laser ranging value and altitude corresponding to each sampling point in the echo signal, specifically, using the satellite position coordinates, the longitude and latitude corresponding to the laser radar pointing point, the elevation corresponding to the pointing point and the delay time of the echo collection segment, and calculating the ranging value through the laser ranging formula; then using the ranging information to solve the altitude of each sampling point, and matching the echo data collection point to a specific height grid.

3. The method for inverting atmospheric particles using a spaceborne hyperspectral detection lidar according to claim 2, It is characterized in that The laser ranging value r corresponding to each sampling point, that is, the distance from the satellite to the sampling point, is as follows: Where, T d is the delay time of the echo acquisition segment, T a is a fixed time difference between the trigger pulse of the data acquisition and the emission of the laser pulse, N is the number of position points in the echo signal acquisition segment, DA is the sampling frequency of the echo signal, and C is the vacuum light speed; The altitude h of each sampling point is given by the following formula: h=l+dr (13) Where l is the distance from the satellite platform to the pointing point on the ground, d is the elevation of the pointing point, and X 星 , Y 星 , Z 星 is the X, Y, and Z coordinates of the satellite in the coordinate system.

4. The method for inverting atmospheric particles using a spaceborne hyperspectral detection lidar according to claim 1, It is characterized in that The step S4. performs distance and system constant correction on the denoised echo signal to obtain a corrected attenuated backscatter signal, specifically: performs distance and system constant correction on the echo signal, and uses the channel system constants calibrated on orbit and the response parameters and gain coefficients of the detector calibrated on the ground to obtain the attenuated backscatter coefficients of the three channels.

5. The method for inverting atmospheric particles using a spaceborne hyperspectral detection lidar according to claim 1, It is characterized in that The step S5. specifically analyzes the temperature and pressure profiles provided by the meteorological data set, the S6 atmospheric model and the absorption spectrum of the iodine molecular filter according to the numerical weather forecast model, establishes a molecular transmittance lookup table for the hyperspectral channel, and calculates the aerosol transmittance and atmospheric molecular parameters of the hyperspectral channel.

6. The method for inverting atmospheric particles using a spaceborne hyperspectral detection lidar according to claim 1, It is characterized in that The step S6. uses the attenuated backscattering signal, the molecular transmittance lookup table, the aerosol transmittance and the atmospheric molecular parameters to preliminarily invert the aerosol backscattering coefficient β a (r), and calculate the atmospheric scattering ratio R(r), the formula is as follows: Where, T m (r) and T a (r) respectively represent the transmittance of the molecular Rayleigh scattering echo signal and the aerosol Mie scattering echo signal after passing through the iodine molecular filter of the hyperspectral channel at the detection distance r; δ(r) is the total depolarization ratio of the atmosphere, expressed as the ratio of the attenuated backscattering coefficient of the polarized channel to the attenuated backscattering coefficient of the reference parallel channel; K(r) is the ratio of the attenuated backscattering coefficient of the reference parallel channel to the hyperspectral channel; δ m is the depolarization ratio of atmospheric molecules, β m (r) is the backscattering coefficient of atmospheric molecules.

7. The method for inverting atmospheric particles using a spaceborne hyperspectral detection lidar according to claim 1, It is characterized in that The step 7 calculates the voltage signal-to-noise ratio UNR of the receiving channel based on the original voltage echo signal and the background noise of the corresponding high-altitude clean atmosphere area. i (r), the formula is as follows: Where U i (r) represents the original voltage signal of the receiving channel, represents the average value of the background noise in the high-altitude clean atmosphere area of ​​the receiving channel, i=⊥, || represents the polarization and parallel components.

8. The method for inverting atmospheric particles using a spaceborne hyperspectral detection lidar according to claim 1, It is characterized in that In step 10, the atmospheric optical thickness τ(r) and the aerosol extinction coefficient α are calculated. a (r), extinction coefficient of atmospheric molecules α m (r), aerosol radar ratio S a (r), the formula is as follows: Where τ(r) is the atmospheric optical thickness; is the attenuated backscattering coefficient of the hyperspectral channel.

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