Cooperative correction of hyperspectral resolution lidar based on field of view division

Abstract

The application discloses a kind of based on field of view division's cooperative correction hyperspectral resolution lidar, including laser emission system, multiple field of view correction receiving system and data acquisition processing system;Multiple field of view correction receiving system is used for receiving echo signal from atmospheric backscattering by designing multiple functional division field of view and is converted into electrical signal, and data acquisition processing system is used for collecting and processing electrical signal received by multiple field of view correction receiving system.The present application effectively makes up for the lack of low high-altitude signal correction of previous hyperspectral resolution lidar system, designs correction range by signal analysis to main field of view, according to the established overlap factor model and nonlinear optimization iterative function to solve the hardware parameters of correction field of view, add correction field of view into system, and the low-altitude blind area signal and high-altitude multiple scattering signal can be cooperatively corrected, the dynamic detection range of system is expanded, and the inversion precision of cloud and aerosol optical property parameters is improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of laser radar detection, and particularly relates to a high-spectral-resolution laser radar based on field-of-view division and cooperative correction. BACKGROUND

[0002] The interaction between aerosols and clouds is the largest source of uncertainty in climate change research. High-precision synchronous observation of aerosols and clouds helps to clarify the action process and mechanism, and is an indispensable means in cloud formation, weather prediction, and climate change research. Aerosols are solid or liquid particles suspended in the atmosphere. For climate change, aerosols can directly affect the radiation balance of the earth-atmosphere system by scattering and absorbing solar radiation. Aerosols can also act as cloud condensation nuclei (CCN) to participate in the generation, evolution and dissipation of clouds, change the phase of clouds, and affect the life cycle and precipitation efficiency of clouds, thereby indirectly affecting regional weather and global climate.

[0003] High-spectral-resolution lidar is a new type of active remote sensing detection instrument. It can accurately retrieve the optical properties of clouds and aerosols without assuming the lidar ratio, and is currently widely used for all-weather, high-precision observation of atmospheric particles. However, due to the overlapping area of the receiving and transmitting fields of view of the lidar system, there will be a detection blind zone below the atmospheric boundary layer (1-2 km) and the accuracy of the retrieval results depends on the accuracy of the overlap factor calibration. Meanwhile, due to the multiple scattering effect of water clouds, the lidar cannot accurately retrieve the single scattering optical and microphysical properties of water clouds.

[0004] Existing high-spectral-resolution lidars mainly use a single field-of-view receiving system. Due to the limitation of the dynamic range of the acquisition module, they cannot simultaneously achieve high-precision detection of low-altitude blind zone signals and high-altitude multiple scattering signals.

[0005] Chinese patent document CN104777487A discloses an atmospheric aerosol detection high-spectral-resolution lidar, which separates aerosol scattering signals and atmospheric molecular scattering signals through a Fabry-Perot interference narrowband spectral filter to achieve high-precision measurement of atmospheric aerosol optical properties. However, it does not consider the correction of low-altitude blind zone signals and high-altitude multiple scattering signals, and the detection range of the system is limited.

[0006] Chinese patent document CN103308926A discloses a high-spectral-resolution lidar based on field-of-view widening Michelson interferometer, which locks and discriminates frequencies through a field-of-view widening Michelson interferometer filter. However, it does not consider the limitation of the dynamic range of the system, and the system is not comprehensive enough.

[0007] The Chinese patent document with the publication number CN113866793A proposes a selection method for the optimal field of view angle parameters of a hyperspectral resolution lidar for water cloud inversion, but it only discusses and analyzes low-altitude water cloud multiple scattering correction and does not consider the limitation of the actual acquisition module dynamic range and the correction of high-altitude water cloud multiple scattering, and the system is not comprehensive enough.

[0008] The Chinese patent document with the publication number CN110488252A proposes to use an auxiliary telescope to calibrate the overlap factor, but it only corrects the inversion blind area of low-altitude signals, and high-altitude signals cannot be accurately detected due to the limitation of the dynamic range of the acquisition module, and the system is not comprehensive enough.

[0009] Therefore, there is an urgent need for a hyperspectral resolution lidar that can comprehensively correct low-altitude and high-altitude signals to cooperatively correct low-altitude blind area signals and high-altitude water cloud multiple scattering signals under different system configurations. SUMMARY

[0010] To solve the problems in the prior art, the present application provides a hyperspectral resolution lidar based on field of view division for cooperative correction, which can simultaneously detect and correct low-altitude blind area signals and high-altitude water cloud multiple scattering signals.

[0011] A hyperspectral resolution lidar based on field of view division for cooperative correction, comprising a laser emission system, a multi-field-of-view correction receiving system, and a data acquisition and processing system;

[0012] The laser emission system is used to emit laser pulses; the multi-field-of-view correction receiving system is used to receive echo signals from atmospheric backscattering and convert them into electrical signals; and the data acquisition and processing system is used to acquire and process electrical signals received by the multi-field-of-view correction receiving system;

[0013] The multi-field-of-view correction receiving system comprises a main field-of-view channel, a low-altitude blind area correction field-of-view channel, and a high-altitude multiple scattering correction field-of-view channel; each field-of-view channel comprises a telescope, a field-of-view diaphragm, a converging lens, an interference filter, a half-wave plate, a polarization beam splitter prism, a spectral frequency discriminator, and a photodetector; the telescope is used to collect echo signals from atmospheric backscattering, the field-of-view diaphragm is used to adjust the receiving field-of-view angle, the converging lens is used to accurately receive light signals, the interference filter is used to suppress light signals outside the target wavelength, the half-wave plate is used to adjust the polarization direction of the signal light, the polarization beam splitter prism is used to separate the polarization components of the light signal, the spectral frequency discriminator is used to suppress aerosol Mie scattering signals, and the photodetector is used to convert the collected light signals into analog electrical signals;

[0014] The emission optical axis of the laser emission system is parallel to the receiving optical axis of the telescope in each field of view channel. The distance between the receiving optical axis and the emission optical axis of the telescope in the main field of view channel and the corresponding receiving field of view angle are used to determine the distance between the receiving optical axis and the emission optical axis of the telescope in the other two field of view channels and the corresponding receiving field of view angle.

[0015] Furthermore, the laser emission system includes a solid-state pulsed laser and a beam expander. The solid-state pulsed laser is used to emit pulsed laser light into the atmosphere, and the beam expander is used to adjust the divergence angle of the pulsed laser light.

[0016] Furthermore, the solid-state pulsed laser operates at a wavelength of 355nm, 532nm, or 1064nm, with a single pulse energy of not less than 4mJ and a pulse width of not more than 10ns.

[0017] Furthermore, the spectral discriminator in the multi-field-of-view correction receiving system employs an atomic / molecular absorption cell, a field-widening Michelson interferometer, or an FP etalon; the receiving field of view of the telescope in the low-altitude blind zone correction field of view channel and the high-altitude multiple scattering correction field of view channel is not less than 1 mrad.

[0018] Furthermore, the main field-of-view channel also includes a vertical polarization channel and a parallel polarization channel for collecting the polarization components of the optical signal.

[0019] Furthermore, the distance between the receiving optical axis and the transmitting optical axis of the telescope in the other two field-of-view channels, as well as the corresponding receiving field-of-view angle, are determined. The specific process is as follows:

[0020] Step S1: Establish the overlap factor model based on the distance between the receiving optical axis and the transmitting optical axis of the telescope in the main field of view channel. and the corresponding receiving field of view. Calculate the overlap factor of the main field of view. ;

[0021] Step S2: Calculate the Rayleigh scattering signal of atmospheric molecules based on the standard atmospheric model. Rayleigh scattering signal of atmospheric molecules Overlap factor with main field of view Multiply to obtain the echo signal ;

[0022] Step S3, based on the effective dynamic range of the acquisition card in the data acquisition and processing system. Calculate the effective echo signal ,according to Determine the detection range of the main field of view. ;

[0023] Step S4, based on the detection range of the main field of view Design low-altitude blind zone signal correction range and high-altitude multiple scattering signal correction range ;

[0024] Step S5, the 、 respectively into the nonlinear optimization iteration function, the solution is obtained low-altitude blind area correction field of view channel of the receiving optical axis and the optimal spacing of the emission optical axis of the telescope and the corresponding optimal receiving field angle , the optimal spacing of the receiving optical axis and the emission optical axis of the telescope in the high-altitude multiple scattering correction field of view channel and the corresponding optimal receiving field angle .

[0025] In step S1, the overlap factor model takes the center point of the receiving telescope as the coordinate origin, the positive direction of the z-axis is vertically upward, the receiving surface of the telescope is the plane of z=0, the divergence angle of the outgoing spot is , the diameter of the outgoing spot is , the receiving field angle of the telescope is , the spot center point is projected to the corresponding point on the z=0 plane , the direction is the positive direction of the y-axis, the spacing between the receiving optical axis and the emission optical axis is , the x-axis is perpendicular to the z-axis and the y-axis. The receiving diameter of the reflecting telescope is , the diameter of the blocking area is . The radius of the emission spot at height z is , the receiving cross-sectional radius is , and the blocking cross-sectional radius of the intermediate secondary mirror is , 、 The overlapping area of the emission spot cross section at height z and the receiving cross section and the blocking cross section of the telescope is:

[0026] ;

[0027] ;

[0028] When the emission spot cross section partially overlaps the receiving cross section, is the angle from the center of the emission cross section to the overlapping area, is the angle from the center of the receiving cross section to the overlapping area; when the emission spot cross section partially overlaps the blocking cross section, is the angle from the center of the emission cross section to the overlapping area, is the angle from the center of the blocking cross section to the overlapping area. The expression is as follows:

[0029] ;

[0030] ;

[0031] ;

[0032] ;

[0033] The overlap factor at height z is:

[0034] .

[0035] In step S2, the Rayleigh scattering signal of atmospheric molecules The calculation formula is:

[0036] ;

[0037] in, The backscattering coefficient of atmospheric molecules. This is the extinction coefficient of atmospheric molecules, and its value is obtained from the standard atmospheric model.

[0038] The specific process of step S3 is as follows:

[0039] Effective dynamic range of the data acquisition card The actual number of valid bits of the data acquisition card The decision is made using the following formula:

[0040] ;

[0041] echo signal After normalization, the signal strength corresponding to its peak point is ,calculate Then the effective echo signal for Middle falls in the range Internal signals;

[0042] exist Search in The corresponding altitude point before the peak is The starting point of the main field of view detection range is ;exist Search in The corresponding height point after the peak is Then the detection range of the main field of view reaches the farthest point. The main field of view detection range is .

[0043] In step S4, the low-altitude blind zone signal correction range The lower limit is lower than the detection range of the main field of view. The lower limit is between the main field of view detection range, and the upper limit is between the high-altitude multiple scattering signal correction range. According to the actual observed height of the cloud.

[0044] The specific process of step S5 is:

[0045] S5-1, constructing the objective function of nonlinear optimization iteration :

[0046] ;

[0047] Wherein, Indicates the parameter in the low-altitude blind area correction field of view channel or the high-altitude multiple scattering correction field of view channel The field of view detection range corresponding to the group of parameters calculated by the same method of the main field of view channel in steps S1-S3;

[0048] S5-2, based on the low-altitude blind area signal correction range , set the initial value of the optimization parameter of the low-altitude blind area correction field of view channel With search boundary, repeat the same method of the main field of view channel in steps S1-S3, calculate the field of view detection range corresponding to the group of initial parameters, and calculate the value of the objective function;

[0049] After calculation, the field of view detection range and the value of the objective function corresponding to the next group of parameters are calculated according to the search boundary condition iteration; after traversing all search values, Corresponding That is the optimal solution of the low-altitude blind area signal correction range ;

[0050] S5-3, based on the high-altitude multiple scattering signal correction range , using the same method as S5-2, a group of optimal .

[0051] Compared with the prior art, the present application has the following beneficial effects:

[0052] 1. The present application adopts the way of different correction field of view working together to construct a hyperspectral resolution lidar system. It makes up for the deficiency of the previous hyperspectral resolution lidar system without considering high and low altitude signal correction, realizes the collaborative correction of low-altitude blind area signal and high-altitude multiple scattering signal, and improves the inversion accuracy of cloud and aerosol optical property parameters.

[0053] 2. This invention adopts a model-optimized reverse hardware parameter design method. By analyzing the main field of view signal to select the correction range, and solving the hardware parameters of the correction field of view according to the established overlap factor model and nonlinear optimization iterative function, the correction field of view can be added to the system to coordinate the correction of low-altitude blind zone signals and high-altitude multiple scattering signals, thereby expanding the dynamic detection range of the system. Attached Figure Description

[0054] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0055] Figure 1 This is a schematic diagram of a collaborative correction hyperspectral resolution lidar structure based on field-of-view division of labor, according to an embodiment of the present invention.

[0056] Figure 2 This is a schematic diagram of the overlap factor model in an embodiment of the present invention.

[0057] Figure 3 This is a schematic diagram of the overlap factor of the system in different fields of view in an embodiment of the present invention.

[0058] Figure 4 This is a trend diagram of the dynamic range of the signal under different fields of view in the embodiment of the present invention. Detailed Implementation

[0059] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0060] It should be noted that, unless otherwise specified, the features in the following embodiments and implementation methods can be combined with each other.

[0061] like Figure 1 As shown, a collaboratively corrected hyperspectral resolution lidar based on field-of-view division of labor includes a laser emitting system, a multi-field-of-view correction receiving system, and a data acquisition and processing system. The laser emitting system emits laser pulses, the multi-field-of-view correction receiving system receives echo signals from the atmosphere and converts them into electrical signals, and the data acquisition and processing system acquires and processes the electrical signals received by the multi-field-of-view correction receiving system.

[0062] The laser emission system comprises a solid pulse laser 1-1 and a beam expander 1-2.

[0063] The multi-field-of-view correction receiving system comprises a main field-of-view channel 2-1, a low-altitude blind area correction field-of-view channel 2-2 and a high-altitude multiple scattering correction field-of-view channel 2-3.

[0064] The main field-of-view channel 2-1 comprises a main field-of-view telescope 2-1-1, a main field-of-view field stop 2-1-2, a main field-of-view converging lens 2-1-3, a main field-of-view mirror 2-1-4, a main field-of-view half-wave plate 2-1-5, a main field-of-view interference filter 2-1-6, a main field-of-view polarization beam splitter 2-1-7, a main field-of-view converging lens 2-1-8, a main field-of-view photodetector 2-1-9, a main field-of-view depolarization beam splitter 2-1-10, a main field-of-view spectral frequency discriminator 2-1-11, a main field-of-view converging lens 2-1-12, a main field-of-view photodetector 2-1-13, a main field-of-view reflecting prism 2-1-14, a main field-of-view converging lens 2-1-15 and a main field-of-view photodetector 2-1-16.

[0065] The low-altitude blind area correction field-of-view channel 2-2 comprises a low-altitude blind area correction field-of-view telescope 2-2-1, a low-altitude blind area correction field-of-view field stop 2-2-2, a low-altitude blind area correction field-of-view converging lens 2-2-3, a low-altitude blind area correction field-of-view mirror 2-2-4, a low-altitude blind area correction field-of-view half-wave plate 2-2-5, a low-altitude blind area correction field-of-view interference filter 2-2-6, a low-altitude blind area correction field-of-view polarization beam splitter 2-2-7, a low-altitude blind area correction field-of-view spectral frequency discriminator 2-2-8, a low-altitude blind area correction field-of-view converging lens 2-2-9 and a low-altitude blind area correction field-of-view photodetector 2-2-10.

[0066] The high-altitude multiple scattering correction field-of-view channel 2-3 comprises a high-altitude multiple scattering correction field-of-view telescope 2-3-1, a high-altitude multiple scattering correction field-of-view field stop 2-3-2, a high-altitude multiple scattering correction field-of-view converging lens 2-3-3, a high-altitude multiple scattering correction field-of-view half-wave plate 2-3-4, a high-altitude multiple scattering correction field-of-view interference filter 2-3-5, a high-altitude multiple scattering correction field-of-view polarization beam splitter 2-3-6, a high-altitude multiple scattering correction field-of-view spectral frequency discriminator 2-3-7, a high-altitude multiple scattering correction field-of-view converging lens 2-3-8 and a high-altitude multiple scattering correction field-of-view photodetector 2-3-9.

[0067] The distance between the optical axes of the low-altitude blind area correction field-of-view channel 2-2 and the high-altitude multiple scattering correction field-of-view channel 2-3 and the optical axis of the laser emission system and the field-of-view angle of the telescope are designed according to the main field-of-view parameters, the center of the field stop is arranged on the focal plane of the telescope and the converging lens, the optical axes of the receiving channels are parallel to and adjacent to the optical axis of the emission channel.

[0068] The data acquisition and processing system comprises a data acquisition card 3-1 and a computer 3-2. The data acquisition card 3-1 is connected to the photoelectric detector of the multi-view field correction receiving system through a coaxial cable, and the computer 3-2 is connected to the data acquisition card 3-1 through a wire.

[0069] In this embodiment, the solid-state pulse laser adopts a solid-state pulse laser with a working wavelength of 532 nm, a single pulse energy of not less than 4 mJ, a pulse width of not more than 10 ns, and a bandwidth of not more than 100 MHz, for example, a narrow-band solid-state pulse laser developed by Zhejiang University, with a working wavelength of 532.62 nm, a single pulse energy of 10 mJ, a pulse width of 3 ns, and a bandwidth of 70 MHz.

[0070] The beam expander adopts a strong laser-resistant beam expander, for example, a BE02-532 model high-power expander of Thorlabs Company, USA, with a 3 times expansion.

[0071] The main-view field interference filter, the low-altitude blind area correction view field interference filter, and the high-altitude multiple scattering correction view field interference filter all adopt an interference filter with a center wavelength of 532 nm and a bandwidth of not more than 3 nm, for example, a 7041 532.2-0.3 OD6 filter of Alluxa Company, USA, with a center wavelength of 532.2 nm and a bandwidth of 0.3 nm.

[0072] The photoelectric detector adopts a photomultiplier tube with a spectral response range of 185-730 nm, a typical cathode light sensitivity of not less than 120 μA / lm, and a rise time of not more than 2.2 ns, for example, a H10721 model photomultiplier tube of Hamamatsu Photonics Company, Japan, with a spectral response range of 230-700 nm, a typical cathode light sensitivity of 135 μA / lm, and a rise time of 0.57 ns.

[0073] The data acquisition card adopts a data acquisition card with a sampling rate of not less than 20 MSa / s and a quantization bit number of not less than 12 bits, for example, a M2p.5923-x4 high-speed data acquisition card of Spectrum, Germany, with a sampling rate of 20 MSa / s and a quantization bit number of 16 bits.

[0074] Based on the above high-spectral-resolution laser radar, the design process of the correction view field is as follows:

[0075] Firstly, a superposition factor model is established according to the hardware system parameters of the laser radar, the distance between the receiving optical axis and the transmitting optical axis of the telescope in the main view field channel is calculated , and the corresponding receiving view field angle is calculated, so as to calculate the main view field superposition factor . As shown in Figure 2 , in this embodiment, the distance between the receiving optical axis of the main view field telescope and the transmitting optical axis of the laser is is 295 mm, the receiving field of view angle is 1 mrad. The overlap factor model takes the center point O of the receiving telescope as the coordinate origin, The positive direction of the axis is vertically upward, the receiving surface of the telescope is taken as the plane, the outgoing light spot divergence angle is 0.5 mrad, the spot diameter at height z is 0.02 m, the receiving field of view angle of the telescope is 1 mrad, the center point of the spot is projected to the corresponding point on the z=0 plane is , The positive direction of the axis is vertically upward, the receiving surface of the telescope is taken as the plane, the outgoing light spot divergence angle is 0.5 mrad, the receiving diameter of the reflecting telescope is 0.28 m, the diameter of the blocking region is 0.08 m, the outgoing light spot radius at height z is , the receiving cross-sectional radius is , the blocking cross-sectional radius of the intermediate secondary mirror is , , The overlapping area of the outgoing light spot cross section at height z and the receiving cross section and the blocking cross section of the telescope is:

[0076] ;

[0077] ;

[0078] When the outgoing light spot cross section partially overlaps with the receiving cross section, is the angle subtended from the center of the outgoing cross section to the overlapping region, is the angle subtended from the center of the receiving cross section to the overlapping region; when the outgoing light spot cross section partially overlaps with the blocking cross section, is the angle subtended from the center of the outgoing cross section to the overlapping region, is the angle subtended from the center of the blocking cross section to the overlapping region. The expressions are as follows:

[0079] ;

[0080] ;

[0081] ;

[0082] ;

[0083] Then the overlap factor at height z is:

[0084] .

[0085] Secondly, according to the standard atmospheric model, the atmospheric molecular Rayleigh scattering signal is calculated The formula of the atmospheric molecular Rayleigh scattering signal is as follows:

[0086] ;

[0087] Wherein, is the atmospheric molecular backscattering coefficient, is the atmospheric molecular extinction coefficient, the value of which is obtained according to the standard atmospheric model. The laser radar echo signal is obtained by multiplying the overlap factor and the atmospheric molecular Rayleigh scattering signal .

[0088] Thirdly, the effective echo signal is calculated based on the effective dynamic range of the acquisition card, and the field of view detection range is determined. The actual effective number of bits of the acquisition module is 10, and according to the formula:

[0089] ;

[0090] The effective dynamic range of the acquisition card is about 60dB. After normalization, the peak point corresponds to a signal intensity of 1000mV, and the effective echo signal , is 1mV, then the effective echo signal is the signal falling within this interval [1mV, 1000mV].

[0091] In , the height point corresponding to 1mV before the peak is 0.19km, so the starting point of the field of view detection range is 0.19km; in , the height point corresponding to 1mV after the peak is 12km, so the farthest detection range of the field of view reaches 12km, and the field of view detection range is (0.19km, 12km).

[0092] Fourthly, according to the effective echo signal of the main field of view, the low-altitude blind area signal correction range (0.01km, 2.4km) and the high-altitude multiple scattering signal correction range (0.27km, 8km) are designed.

[0093] Fifthly, (0.01km, 2.4km) and (0.27km, 8km) are respectively brought into the nonlinear optimization iteration function, and the nonlinear optimization iteration objective function is constructed as follows:

[0094] ;

[0095] ;

[0096] According to the initial value of the optional hardware setting optimization parameter and the search boundary, the search boundary is set to (1.1 mrad, 3.5 mrad), (70 mm, 1000 mm), and after the initial value is set to [2 mrad, 150 mm], steps one to three are repeated, the detection range corresponding to the group of parameters is calculated , and the value of the objective function is calculated.

[0097] After the calculation, the detection range corresponding to the next group of parameters is iteratively calculated according to the search boundary condition and the value of the objective function, until all search values are traversed. After all search values are traversed, the low-altitude blind area correction field of view objective function corresponding to is [2.3 mrad, 75 mm]; the high-altitude multiple scattering signal correction range field of view objective function corresponding to is [2.5 mrad, 500 mm].

[0098] The optimal field of view angle of the telescope corresponding to the low-altitude blind area correction field of view is 2.3 mrad, and the optimal distance from the emission optical axis is 75 mm; the optimal field of view angle of the telescope corresponding to the high-altitude multiple scattering correction field of view is 2.5 mrad, and the distance from the emission optical axis is 500 mm.

[0099] The main field of view and the correction field of view overlap factor curve obtained according to the embodiment design is shown in Figure 3 , the main field of view overlap factor transition zone range is 190 m-3600 m, the low-altitude blind area correction field of view overlap factor transition zone range is 10 m-150 m, and the high-altitude multiple scattering correction field of view overlap factor transition zone is 270 m-630 m.

[0100] The main field of view and the correction field of view signal detection dynamic range is shown in Figure 4 , the main field of view effective detection range is up to 12 km, the low-altitude blind area correction field of view effective detection range is up to 2.4 km, and the signal in the low-altitude inversion blind area of the main field of view is corrected; the high-altitude multiple scattering correction field of view effective detection range is up to 8 km, and the multiple scattering signal in the high-altitude full area of the main field of view is corrected.

[0101] The above embodiments of the present application are described in detail, and it should be understood that the above embodiments are only specific embodiments of the present application, and are not used to limit the present application, and any modification, supplement and equivalent replacement made within the principle range of the present application should be included in the protection range of the present application.

Claims

1. A cooperative correction hyperspectral resolution lidar based on field of view division, characterized in that, The laser emission system, the multi-view field correction receiving system and the data acquisition and processing system are included. The laser emission system is used for emitting laser pulses; the multi-view field correction receiving system is used for receiving echo signals from atmospheric backscattering and converting into electric signals; and the data acquisition and processing system is used for acquiring and processing the electric signals received by the multi-view field correction receiving system. The multi-view field correction receiving system includes a main view field channel (2-1), a low-altitude blind area correction view field channel (2-2) and a high-altitude multi-scattering correction view field channel (2-3); each view field channel includes a telescope, a view field diaphragm, a converging lens, an interference filter, a half-wave plate, a polarization beam splitter prism, a spectral frequency discriminator and a photoelectric detector. The emission optical axis of the laser emission system and the receiving optical axis of the telescope in each view field channel are parallel; the interval between the receiving optical axis of the telescope and the emission optical axis in the main view field channel (2-1) and the corresponding receiving view field angle are determined, and the interval between the receiving optical axis of the telescope and the emission optical axis in the other two view field channels and the corresponding receiving view field angle are determined.

2. The synergistic corrected hyperspectral resolution lidar based on field-of-view partitioning of claim 1, wherein, The laser emission system includes a solid pulse laser (1-1) and a beam expander (1-2); the solid pulse laser (1-1) is used for emitting pulse laser into the atmosphere; and the beam expander (1-2) is used for adjusting the divergence angle of the pulse laser.

3. The synergistic corrected hyperspectral resolution lidar based on field-of-view division according to claim 2, characterized in that, The working wavelength of the solid pulse laser (1-1) is 355 nm, 532 nm or 1064 nm; the single pulse energy is not less than 4 mJ; and the pulse width is not more than 10 ns.

4. The collaboratively corrected hyperspectral resolution lidar based on field-of-view partitioning of claim 1, wherein, The spectral frequency discriminator in the multi-view field correction receiving system (2) adopts an atomic / molecular absorption cell, a view field widening Michelson interferometer or an FP standard device; the receiving view field angle of the telescope in the low-altitude blind area correction view field channel (2-2) and the high-altitude multi-scattering correction view field channel (2-3) is not less than 1 mrad.

5. The collaboratively corrected hyperspectral resolution lidar based on field-of-view partitioning of claim 1, wherein, The main view field channel (2-1) further includes a vertical polarization channel and a parallel polarization channel for collecting polarization components of optical signals.

6. The collaboratively corrected hyperspectral resolution lidar based on field-of-view partitioning of claim 1, wherein, The interval between the receiving optical axis of the telescope and the emission optical axis in the other two view field channels and the corresponding receiving view field angle are determined, and the specific process is as follows: Step S1, establishing an overlap factor model, according to the distance between the receiving optical axis and the transmitting optical axis of the telescope in the main field of view channel and the corresponding receiving field of view angle , calculating the main field of view overlap factor ; wherein the receiving surface of the telescope is taken as the plane of , indicates the height; Step S2, calculate atmospheric molecular Rayleigh scattering signal according to standard atmospheric model , multiply atmospheric molecular Rayleigh scattering signal with main field of view overlap factor to obtain echo signal ; Step S3, determining the detection range of the main field of view based on the effective dynamic range of the acquisition card in the data acquisition processing system , calculating the effective echo signal , according to determine the detection range of the main field of view ; Step S4, according to the main field of view detection range Design low altitude blind area signal correction range And high altitude multiple scattering signal correction range ; Step S5, the , are respectively brought into the nonlinear optimization iteration function, and the optimal distance between the receiving optical axis and the transmitting optical axis of the telescope in the low-altitude blind area correction field of view channel and the corresponding optimal receiving field of view angle , the optimal distance between the receiving optical axis and the transmitting optical axis of the telescope in the high-altitude multi-scattering correction field of view channel and the corresponding optimal receiving field of view angle are solved.

7. The collaboratively corrected hyperspectral resolution lidar based on field-of-view partitioning of claim 6, wherein, In step S2, the atmospheric molecule Rayleigh scattering signal The calculation formula is: ； wherein, is the atmospheric molecular backscatter coefficient, is the atmospheric molecular extinction coefficient.

8. The collaboratively corrected hyperspectral resolution lidar based on field-of-view partitioning of claim 6, wherein, The specific process of step S3 is as follows: effective dynamic range of the acquisition card by the actual effective number of bits of the acquisition card determined by the formula: ； The echo signal is normalized to have a peak value of 1, i.e. , and the normalized echo signal is calculated as The effective echo signal is then given by where the signal falls in the interval ​ In , find , the height point corresponding to the peak before , the starting point of the main field of view detection range is ; in , find , the height point corresponding to the peak after , the main field of view detection range reaches as far as , and the main field of view detection range is .

9. The collaboratively corrected hyperspectral resolution lidar based on field-of-view partitioning of claim 6, wherein, In step S4, the low-altitude shadow zone signal correction range has a lower limit below the lower limit of the main field of view detection range and an upper limit between the upper limits of the main field of view detection range; the high-altitude multi-scattering signal correction range is determined according to the height of the actually observed cloud.

10. The collaboratively corrected hyperspectral resolution lidar based on field-of-view partitioning of claim 6, wherein, The specific process of step S5 is as follows: S5-1, construct objective function for nonlinear optimization iteration : ； wherein, denotes the parameters in the low-altitude blind area correction FOV channel or the high-altitude multi-scattering correction FOV channel The FOV detection range corresponding to the set of parameters calculated by the same method as the main FOV channel in steps S1-S3; S5-2, correcting the range based on the low-altitude blind area signal , setting the initial value of the optimization parameter of the low-altitude blind area correction field channel Repeat steps S1-S3 in the main field of view channel to calculate the field of view detection range corresponding to the set of initial parameters, and calculate the value of the objective function. After the calculation, the field of view detection range corresponding to the next set of parameters and the target function value are calculated according to the search boundary condition iteratively; after all the search values are traversed, Correspondingly That is, the optimal solution of the low-altitude blind area signal correction range Under S5-3, correction range based on high-altitude multi-scattering signals , using the same method as S5-2, a set of optimal .

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