Blind-zone-free laser remote sensing system and method for stabilizing boundary layer thermodynamic material structure

Abstract

This invention discloses a blind-zone-free laser remote sensing system for stable boundary layer thermal material structures. The system includes a lateral scanning Raman scattering lidar receiving system with multiple lateral receiving systems, a lidar transmitting system, and a backscattering Raman scattering lidar receiving system. The lateral receiving system receives near-surface nitrogen and water vapor Raman signals and aerosol Mie-Rayleigh scattering signals, filling the detection blind zone of the backscattering lidar. The backscattering system detects signals in the upper atmosphere. The invention also discloses a blind-zone-free laser remote sensing method for stable boundary layer thermal material structures, which utilizes the lateral and backscattering systems for collaborative observation, respectively retrieving the water vapor mixing ratio, temperature, and aerosol extinction coefficient near the ground and in the upper atmosphere, and fusing them through a data stitching algorithm to obtain a blind-zone-free profile of the entire layer. This method enables refined detection of the entire layer from the ground to the upper atmosphere, continuously, with full parameters, and high spatiotemporal resolution.

Description

Technical Field

[0001] This invention belongs to the field of atmospheric temperature, water vapor, and aerosol detection technology, specifically relating to a blind-zone-free laser remote sensing system for stable boundary layer thermal material structures, and also to a blind-zone-free laser remote sensing method for stable boundary layer thermal material structures. Background Technology

[0002] The atmospheric boundary layer is the part of the troposphere directly affected by the Earth's surface. Its response timescale to surface forcing forces (friction, evaporation and transpiration, heat transfer, pollutant emissions, and rheological properties induced by topography) is approximately one hour or less. As the bottom layer of the Earth's atmosphere upon which humanity depends for survival, the atmospheric boundary layer structure significantly influences the accumulation and transport of air pollutants, determining changes in air quality. Studying the refined structure of the atmospheric boundary layer has significant scientific and applied value for understanding atmospheric environmental changes and is a hot topic in scientific research.

[0003] The atmospheric boundary layer structure exhibits a diurnal cycle, primarily driven by incident solar radiation. During the day, the convective boundary layer develops under the influence of solar radiation absorbed by the Earth's surface, causing heat, kinetic energy, water vapor, and pollutants to mix within it. After sunset, the ground cools radiatively, and the atmospheric boundary layer cools from bottom to top, gradually developing into a stable boundary layer with an inversion stratification. During inversion stratification, turbulence must work against gravity, consuming kinetic energy, thus inhibiting turbulent exchange. This results in a much weaker development of the stable boundary layer at night compared to the daytime mixing layer, a significantly lower atmospheric boundary layer height, and the beginning of a residual layer above the stable boundary layer. This residual layer retains some properties and meteorological parameters present in the daytime convective boundary layer, including residual heat, water vapor, pollutants, and the overlying inversion layer.

[0004] Currently, boundary layer research mainly focuses on the daytime convective boundary layer, while there is not much research on the nighttime stable boundary layer. The main reason is the lack of measurement methods that can achieve full field of view and high spatiotemporal resolution for stable boundary layers with heights of only a few hundred meters to a kilometer.

[0005] While lidar is an advanced atmospheric profile detection device with high spatiotemporal resolution and precision, capable of simultaneously and continuously detecting atmospheric temperature, water vapor, wind field, and aerosols, it possesses unique advantages in nighttime boundary layer structure detection. However, its operating principle inherently introduces blind spots, resulting in missing lower-level data. Therefore, current technologies cannot meet the demands of nighttime stable boundary layer detection, necessitating the development of a refined detection technology capable of acquiring full-layer, continuous, comprehensive, and high spatiotemporal resolution profiles. Summary of the Invention

[0006] The first objective of this invention is to provide a blind-zone-free laser remote sensing system for the thermal material structure of stable boundary layers. This system can overcome the deficiency of missing low-level data and achieve fine-grained detection of the entire stable boundary layer, continuously, with full parameters and high spatiotemporal resolution.

[0007] The second objective of this invention is to provide a blind-zone-free laser remote sensing method for the thermal material structure of stable boundary layers, enabling fine-grained detection of the entire stable boundary layer, continuously, with full parameters, and high spatiotemporal resolution. This solves the problem of "incomplete and incomplete measurement" caused by the existence of detection blind zones in existing lidar equipment.

[0008] The first technical solution adopted in this invention is a blind-zone-free laser remote sensing system for stabilizing the thermal material structure of the boundary layer, comprising a lateral scanning Raman scattering lidar receiving system with multiple lateral receiving systems, a lidar transmitting system, and a backscattering Raman scattering lidar receiving system.

[0009] The invention is further characterized in that:

[0010] A lateral scanning Raman scattering lidar receiving system with multiple lateral receiving systems includes several lateral receiving systems; The lateral receiving system is used to receive lateral Raman scattering echo signals and Mi-Rayleigh scattering echo signals from nitrogen, water vapor and aerosols in the atmosphere, and transmit the received signals to the data acquisition system for acquisition and storage. The backscattering lidar receiving system is used to receive backscattering echo signals of nitrogen and water vapor in the upper atmosphere, and transmit the received signals to the data acquisition system for acquisition and storage. Several lateral receiving systems and a backscattering Raman scattering lidar receiving system share the lidar transmitting system as the excitation light source.

[0011] The lateral receiving system includes an electrically adjustable pitch support and a first data acquisition system. Several sets of lateral telescope assemblies are installed on the electrically adjustable pitch support. The electrically adjustable pitch support is used to drive the lateral telescope assemblies to perform pitch scanning in order to change the detection field of view. Each side-view telescope assembly includes a side-view telescope, and after the light outlet of the side-view telescope, the optical path is sequentially connected to a first collimating lens, a first filter, a first focusing lens, and a first photomultiplier tube. A side-facing telescope is used to receive the side-facing Raman scattering echo signal generated by the interaction of the pulsed laser emitted by the lidar transmitting system with the atmosphere. After being received by the side-facing telescope, the side-facing Raman scattering echo signal is incident on a first collimating lens. The first collimating lens collimates the diverging beam into a parallel beam and then directs it onto a first filter. The first filter performs spectral dispersion processing on the incident parallel beam, allowing only the Raman scattering light signal with a preset center wavelength to pass through. The light signal passing through the first filter is focused and converged by a first focusing lens and then enters a first photomultiplier tube. The first photomultiplier tube is used to detect weak light signals and convert them into electrical signals. The first photomultiplier tube is connected to a first data acquisition system, which is used to perform high-speed acquisition and storage of the electrical signals.

[0012] The lidar transmitting system includes a high-power laser, a laser beam expander, and a reflector connected sequentially via optical paths; the reflector is positioned at a 45° angle relative to the horizontal plane. High-power lasers are used to emit horizontal pulsed lasers of a specific wavelength. The horizontal pulsed laser is collimated and expanded by a laser beam expander and then incident on a reflector. The reflector reflects the incident horizontal laser and directs it perpendicularly toward the atmosphere.

[0013] The backscattering Raman scattering lidar receiving system includes a backscattering telescope, a second collimating lens, a prism, and a spectral splitting system connected in sequence via optical paths; it also includes a second data acquisition system connected to the spectral splitting system. The backscattering telescope is used to receive the backscattered Raman echo signal generated by the interaction of the pulsed laser emitted by the lidar transmitting system with the atmosphere. After being received by the backscattering telescope, the backscattered Raman echo signal is collimated by the second collimating lens and incident on the spectral splitting system under the light guiding effect of the prism. The spectral splitting system is used to perform fine spectral splitting and photoelectric conversion on the incident light signal. The second data acquisition system is used to acquire and store the converted electrical signal.

[0014] The spectral splitting system includes a first beam splitter cube, which is used to split the incident beam after it has been refracted by a prism into a first beam and a second beam that are perpendicular to each other. A second beam splitter is arranged in the optical path of the first beam, which splits the first beam into a third beam and a fourth beam that are perpendicular to each other. In the optical path of the third beam, a second filter, a second focusing lens, and a second photomultiplier tube are arranged in sequence from near to far from the second beam splitter. In the optical path of the fourth beam, a sixth filter, a sixth focusing lens, and a sixth photomultiplier tube are arranged in sequence from near to far from the second beam splitter. A third beam splitter is positioned in the optical path of the second beam, dividing it into two mutually perpendicular beams: a fifth beam and a sixth beam. In the optical path of the sixth beam, a third filter, a third focusing lens, and a third photomultiplier tube are positioned sequentially from the third beam splitter, from closest to furthest. A fourth beam splitter is positioned in the optical path of the fifth beam, dividing it into two mutually perpendicular beams: a seventh beam and an eighth beam. In the optical path of the seventh beam, a fifth filter, a fifth focusing lens, and a fifth photomultiplier tube are positioned sequentially from the fourth beam splitter, from closest to furthest. In the optical path of the eighth beam, a fourth filter, a fourth focusing lens, and a fourth photomultiplier tube are positioned sequentially from the fourth beam splitter, from closest to furthest. The second, third, fourth, fifth, and sixth photomultiplier tubes are all connected to the second data acquisition system.

[0015] The second technical solution adopted in this invention is a blind-zone-free laser remote sensing method for stabilizing the thermal material structure of the boundary layer, which employs the above-mentioned system, specifically: Step 1: Deploy a side-scanning Raman scattering lidar receiving system with multiple side-facing receiving systems; Step 2: Deploy the backscattering Raman lidar receiving system; Step 3: Data Acquisition and Processing.

[0016] The invention is further characterized in that: Step 1 is implemented in the following steps: Step 1.1, System Layout: Install the lidar transmitting system at the observation location; determine the horizontal spacing between the lateral receiving system and the lidar transmitting system based on the required distance resolution of the target detection area. D ; Step 1.2, Resolution Adjustment: Adjust the scanning cycle of the electrically adjustable pitch support and the horizontal spacing distance of the lateral receiving system. D Set the spatial resolution of the lateral receiving system; Among them, the lateral receiving system can operate at any pitch angle. θ Distance resolution d z The calculation formula is as follows:

[0017] In the formula: D The horizontal distance between the lateral receiving system and the lidar transmitting system; dθ This refers to the receiving field of view of the side-mounted telescope; θ The scanning angle of the electrically adjustable pitch support; δ1 represents the initial angle between the optical axis of the side-mounted telescope and the horizontal plane; Step 1.3, Multi-system expansion: Deploy several sets of lateral receiving systems along the optical path according to the detection requirements.

[0018] Step 2 is implemented in the following steps: Step 2.1, Beam Alignment: Deploy the backscattering Raman scattering lidar receiving system so that the field of view of its backscattering telescope coincides with the vertical laser beam emitted by the lidar transmitting system; Step 2.2, Shared Light Source Coordination: Ensure that the backscattering Raman scattering lidar receiving system and the side receiving system share the same pulsed laser emitted by a high-power laser as the excitation source to achieve coordinated observation.

[0019] Step 3 is implemented in the following steps: Step 3.1, Signal Acquisition: Control the high-power laser to emit pulsed laser light; use the first data acquisition system of the lateral receiving system to acquire and store the lateral Raman scattering echo signal and the Mi-Rayleigh scattering echo signal; use the second data acquisition system of the backscattering lidar receiving system to acquire and store the backscattering Raman scattering echo signal and the Mi-Rayleigh scattering echo signal. Step 3.2, the inversion of water vapor mixing ratio and atmospheric temperature, specifically: (1) Water vapor mixing ratio inversion: The atmospheric water vapor mixing ratio is calculated using the following formula. W(z) :

[0020] In the formula: z To detect altitude; C These are system calibration constants; P H (z) The intensity of the received water vapor Raman scattering signal; P N (z) The intensity of the received nitrogen Raman scattering signal; ΔT r This is the atmospheric differential transmittance correction function; Δf r The ratio of phase functions; λ H The Raman wavelength for water vapor; λ N The wavelength is the nitrogen Raman wavelength. (2) Atmospheric temperature inversion: using the ratio of pure rotational Raman scattering signals from high and low quantum number channels Q(z) Inverted atmospheric temperature T(z) :

[0021] In the formula:P Low (z) and P High (z) These represent the intensity of pure rotational Raman scattering signals with low and high quantum numbers obtained after spectral dispersion by the spectral dispersion system; A , B These are the system constants determined through calibration experiments; (3) Inversion of aerosol optical parameters: Using the detected Mie-Rayleigh scattering signal P MR (z) and nitrogen vibration Raman scattering signal P N (z) Calculate the extinction coefficient of aerosols. α aer (z) :

[0022] In the formula: λ 0 represents the emitted laser wavelength; λ N The wavelength is the nitrogen Raman wavelength. N(z) Atmospheric number density; α mol (z) Atmospheric extinction coefficient; k Wavelength index; Step 3.3, Data stitching and full height profile generation: Set the effective detection blind zone height of the backscattering Raman lidar to... h 1. Set the effective detection upper limit height of the lateral receiving system to: h 2, h 1< h 2. Construct a complete, blind-spot-free atmospheric parameter profile from the ground to upper atmosphere using the following stitching algorithm. G Total (z) :

[0023] In the formula: G L(z) These are atmospheric parameters (temperature, water vapor mixing ratio, or aerosol extinction coefficient) obtained by inversion based on the data from the lateral receiving system. G B(z) These are atmospheric parameters obtained by inversion based on data from the backscattering lidar receiving system. w(z) The weighting function for the transition region has values ​​in the interval [ h 1 , h 2] The value changes linearly or nonlinearly from 0 to 1.

[0024] The beneficial effects of this invention are: (1) Achieved full-layer, blind-spot-free detection from the ground surface to high altitude: The system of this invention innovatively adopts a collaborative observation architecture of "lateral receiving system" and "backward Raman scattering lidar receiving system". The lateral receiving system is specifically used to fill the inherent near-ground detection blind zone (e.g., 0-800m) of the backward system. The two share the excitation light source and combine data stitching and fusion algorithms, which effectively solves the problem of missing low-level data in traditional lidar, and achieves full-layer, continuous coverage from the ground surface (0m) to high altitude (e.g., above 3km).

[0025] (2) High spatiotemporal resolution and detection flexibility: The system of this invention can flexibly adjust the horizontal interval distance and scanning cycle of the lateral receiving system according to the detection requirements, thereby obtaining a high spatial resolution of meters in the near-ground region. This enables the system to accurately capture the rapidly changing fine structures (such as inversion layers, water vapor accumulation layers, etc.) within the stable boundary layer at night, overcoming the limitations of traditional radiosonde methods (such as radiosonde balls, weather towers) in terms of spatiotemporal resolution.

[0026] (3) Achieved simultaneous and refined acquisition of multiple atmospheric parameters: The system of this invention can simultaneously detect and invert the vertical profiles of atmospheric temperature, water vapor mixing ratio, and aerosol extinction coefficient using the same system. Through specific weighted fusion processing, the smoothness and consistency of the data in the transition region between the low and high altitudes are guaranteed, providing high-precision scientific data with full parameters (temperature, water vapor, aerosols, etc.) for the study of atmospheric thermal structure.

[0027] (4) It provides a powerful observation tool for the study of atmospheric pollution mechanism: Based on the fine profile data without blind spots obtained by the present invention and the system, it can reveal the structural evolution law of the stable boundary layer and residual layer at night more deeply, and then clarify the influence mechanism of pollutant transport, diffusion and accumulation. It has important scientific significance and application value for improving the level of atmospheric environmental pollution prevention and control.

[0028] (5) The method of the present invention enables fine detection of the entire stable boundary layer, continuously, with all parameters (temperature, water vapor, aerosol, etc.) and high spatiotemporal resolution, solving the problem of "incomplete and incomplete measurement" caused by the existence of detection blind spots in existing lidar equipment. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the blind-zone-free laser remote sensing system for stabilizing the thermal material structure of the boundary layer according to the present invention. Figure 2 This is a schematic diagram of the spectral dispersive system in the blind-zone-free laser remote sensing system for stabilizing the thermal material structure of the boundary layer of the present invention. Figure 3This is a schematic diagram of the calculation model for the field of view and range resolution of the lateral Raman scattering lidar in the method of the present invention; Figure 4 This is a schematic diagram of the structure of the lateral scanning Raman scattering lidar receiving system and the lidar transmitting system with multiple lateral receiving systems in the system of the present invention; Figure 5 This is a flowchart of the blind-zone-free laser remote sensing method for stabilizing the thermal material structure of the boundary layer according to the present invention. Figure 6 This is the range-squared correction signal for the backscattering Raman lidar; Figure 7 The relationship between scattering angle and detection height when the horizontal distance D between the transceiver systems is 50 m, 60 m, 70 m, and 80 m; Figure 8 The data profile and temperature detection results of a side-scanning Raman scattering lidar with a multi-side receiving system are obtained by using a full-segment equidistant resolution configuration scheme. Figure 9 The data profile and atmospheric temperature detection results of a side-scanning Raman scattering lidar with a multi-side receiving system are obtained by adopting a segmented equidistant resolution configuration scheme. Figure 10 The data profile and atmospheric temperature detection results of a side-scanning Raman scattering lidar with a multi-side receiving system are obtained by using a full-segment equidistant resolution configuration scheme. Figure 11 The data profile and atmospheric temperature detection results of a side-scanning Raman scattering lidar with a multi-side receiving system are obtained by adopting a segmented equidistant resolution configuration scheme. Figure 12 The atmospheric temperature inversion results were obtained by combining a side-scanning Raman scattering lidar with a multi-side receiving system and a back-scanning Raman scattering lidar. Figure 13 The results of atmospheric water vapor inversion were obtained by combining a lateral scanning Raman scattering lidar with a multi-lateral receiving system and a backscattering Raman scattering lidar.

[0030] In the diagram, 1. High-power laser, 2. Laser beam expander, 3. Reflector, 4. Rear telescope, 5. Side telescope, 6. First collimating lens, 7. First filter, 8. First focusing lens, 9. First photomultiplier tube, 10. Motorized adjustable pitch support, 11. First data acquisition system, 12. Prism, 13. Spectral beam splitting system, 14. Second data acquisition system, 15. Second collimating lens, 16. First beam splitter cube, 17. Second beam splitter cube, 18. Third... 19. Fourth beam splitter cube, 20. Second filter, 21. Third filter, 22. Fourth filter, 23. Fifth filter, 24. Sixth filter, 25. Second focusing lens, 26. Third focusing lens, 27. Fourth focusing lens, 28. Fifth focusing lens, 29. Sixth focusing lens, 30. Second photomultiplier tube, 31. Third photomultiplier tube, 32. Fourth photomultiplier tube, 33. Fifth photomultiplier tube, 34. Sixth photomultiplier tube. Detailed Implementation

[0031] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0032] This invention provides a blind-zone-free laser remote sensing system for stable boundary layer thermodynamic material structures, such as... Figure 1-4 As shown, it includes a lateral scanning Raman scattering lidar receiving system with multiple lateral receiving systems, a lidar transmitting system, and a backscattering Raman scattering lidar receiving system; A lateral scanning Raman scattering lidar receiving system with multiple lateral receiving systems includes several lateral receiving systems; The lateral receiving system is used to receive lateral Raman scattering echo signals and Mi-Rayleigh scattering echo signals from nitrogen, water vapor and aerosols in the atmosphere, and transmit the received signals to the data acquisition system for acquisition and storage. The main function of this system is to acquire lateral Raman scattering echo signals and Mie-Rayleigh scattering echo signals from the near-surface region, and then retrieve the near-surface water vapor mixing ratio, atmospheric temperature, and aerosol extinction coefficient. Its purpose is to address the inherent near-surface detection blind zone and inability to detect near-surface signals in backscattering lidar systems; the lateral receiving system is specifically designed to fill this blind zone. By combining the lateral and backscattering systems, the problem of not being able to acquire complete data relying solely on the backscattering system is solved, thus achieving blind-zone-free observation of the entire profile from the ground to high altitudes. The backscattering lidar receiving system is used to receive backscattering echo signals of nitrogen and water vapor in the upper atmosphere, and transmit the received signals to the data acquisition system for acquisition and storage. The main function of this system is to invert upper-level atmospheric temperature using the dependence of pure rotational Raman scattering spectra on atmospheric temperature, and to invert the vertical profile of upper-level water vapor using vibrational Raman spectral signals. Its purpose is to address the key challenge of atmospheric parameter detection in the upper atmosphere, acquiring refined detection profiles with high spatiotemporal resolution. It complements the lateral receiving system in the vertical space, providing upper-level data support above the near-surface area within the effective detection range of the lateral system. Several lateral receiving systems and a backscattering Raman scattering lidar receiving system share the lidar transmitting system as the excitation light source.

[0033] The specific working process is as follows: the lidar transmitting system is used to emit pulsed lasers into the atmosphere; the backscattering lidar receiving system is used to receive the backscattering echo signals generated by the interaction of the pulsed laser with nitrogen and water vapor in the atmosphere; and several lateral receiving systems are used to receive the lateral Raman scattering echo signals generated by the interaction of the pulsed laser with nitrogen and water vapor in the atmosphere. The horizontal spacing between several lateral receiving systems and the lidar transmitting system varies.

[0034] The lateral receiving system includes an electrically adjustable pitch support 10 and a first data acquisition system 11. Several sets of lateral telescope assemblies are installed on the electrically adjustable pitch support 10. The electrically adjustable pitch support 10 is used to drive the lateral telescope assemblies to perform pitch scanning in order to change the detection field of view. Each side-view telescope assembly includes a side-view telescope 5, and after the light outlet of the side-view telescope 5, a first collimating lens 6, a first filter 7, a first focusing lens 8 and a first photomultiplier tube 9 are connected in sequence via optical path. The side telescope 5 is used to receive the side Raman scattering echo signal generated by the interaction of the pulsed laser emitted by the lidar transmitting system with the atmosphere. After being received by the side telescope 5, the side Raman scattering echo signal is incident on the first collimating lens 6. The first collimating lens 6 collimates the diverging beam into a parallel beam and then directs it onto the first filter 7. The first filter 7 performs spectral dispersion processing on the incident parallel beam, allowing only the Raman scattering light signal with a preset center wavelength to pass through. The light signal passing through the first filter 7 is focused and converged by the first focusing lens 8 and then enters the first photomultiplier tube 9. The first photomultiplier tube 9 is used to detect weak light signals and convert them into electrical signals. The first photomultiplier tube 9 is connected to the first data acquisition system 11, which is used to perform high-speed acquisition and storage of electrical signals.

[0035] The lidar transmitting system includes a high-power laser 1, a laser beam expander 2, and a reflector 3 connected in sequence via optical paths; the reflector 3 is set at 45° relative to the horizontal plane. A high-power laser 1 is used to emit a horizontal pulsed laser of a specific wavelength. The horizontal pulsed laser is collimated and expanded by a laser beam expander 2 and then incident on a reflector 3. The reflector 3 reflects the incident horizontal laser so that it is directed perpendicularly toward the atmosphere. The pulsed laser directed perpendicularly toward the atmosphere serves as a shared excitation source for the lateral receiving system and the backscattering Raman scattering lidar receiving system. The pulsed laser interacts with nitrogen and water vapor in the atmosphere to generate Raman scattering signals, which are received by the lateral receiving system and the backscattering Raman scattering lidar receiving system, respectively.

[0036] The backscattering Raman lidar receiving system includes a backscattering telescope 4, a second collimating lens 15, a prism 12, and a spectral splitting system 13 connected in sequence via optical paths; it also includes a second data acquisition system 14 connected to the spectral splitting system 13. The back-scattering telescope 4 is used to receive the back-scattering Raman echo signal generated by the interaction of the pulsed laser emitted by the lidar transmitting system with the atmosphere. After being received by the back-scattering telescope 4, the back-scattering Raman echo signal is collimated by the second collimating lens 15 and incident on the spectral splitting system 13 under the refracting and guiding action of the prism 12. The spectral splitting system 13 is used to perform fine spectral splitting and photoelectric conversion on the incident light signal. The second data acquisition system 14 is used to acquire and store the converted electrical signal.

[0037] The spectral splitting system 13 includes a first beam splitting cube 16, which is used to split the incident beam after it has been refracted by the prism 12 into a first beam and a second beam that are perpendicular to each other. A second beam splitter 17 is provided in the optical path of the first beam, which splits the first beam into a third beam and a fourth beam that are perpendicular to each other. In the optical path of the third beam, a second filter 20, a second focusing lens 25 and a second photomultiplier tube 30 are arranged in order from near to far from the second beam splitter 17. In the optical path of the fourth beam, a sixth filter 24, a sixth focusing lens 29 and a sixth photomultiplier tube 34 are arranged in order from near to far from the second beam splitter 17. A third beam splitter 18 is arranged in the optical path of the second beam, which splits the second beam into a fifth beam and a sixth beam that are perpendicular to each other. In the optical path of the sixth beam, a third filter 21, a third focusing lens 26, and a third photomultiplier tube 31 are arranged in order from near to far from the third beam splitter 18. A fourth beam splitter 19 is arranged in the optical path of the fifth beam, which splits the fifth beam into a seventh beam and an eighth beam that are perpendicular to each other. In the optical path of the seventh beam, a fifth filter 23, a fifth focusing lens 28, and a fifth photomultiplier tube 33 are arranged in order from near to far from the fourth beam splitter 19. In the optical path of the eighth beam, a fourth filter 22, a fourth focusing lens 27, and a fourth photomultiplier tube 32 are arranged in order from near to far from the fourth beam splitter 19. The second photomultiplier tube 30, the third photomultiplier tube 31, the fourth photomultiplier tube 32, the fifth photomultiplier tube 33, and the sixth photomultiplier tube 34 are all connected to the second data acquisition system 14. Each of the above photomultiplier tubes is used to detect Raman scattering light signals or Mi-Rayleigh scattering light signals of a specific wavelength after filtering, convert them into electrical signals, and transmit the electrical signals to the second data acquisition system 14 for acquisition and storage.

[0038] Among them, the high-power laser 1 is model SGR-20 Nd:YAG; The first photomultiplier tube 9, the second photomultiplier tube 30, the third photomultiplier tube 31, the fourth photomultiplier tube 32, the fifth photomultiplier tube 33 and the sixth photomultiplier tube 34 are all model PMT, HAMAMATSU H11901; The first bundle cube 16, the second bundle cube 17, the third bundle cube 18, and the fourth bundle cube 19 are all of the THORLABS type. When there are four sets of side-mounted telescope assemblies, the first filter 7 in all four sets of side-mounted telescope assemblies is of the American Andover Corporation; the center wavelengths of the first filter 7 in the four sets of side-mounted telescope assemblies are 533.242nm, 532nm, 535.519nm, 607.7nm, and 660nm, respectively.

[0039] The second filter 20, the third filter 21, the fourth filter 22, the fifth filter 23, and the sixth filter 24 are from Andover Corporation, USA, with center wavelengths of 533.242 nm, 532 nm, 535.519 nm, 607.7 nm, and 660 nm, respectively. The model of the electrically adjustable pitch support is Jucheng CH-W050YT.

[0040] This invention also provides a blind-zone-free laser remote sensing method for stabilizing boundary layer thermodynamic material structures, such as... Figure 5 As shown, the above system is adopted, specifically: Step 1: Deploy a side-scanning Raman scattering lidar receiving system with multiple side-facing receiving systems; Step 1 is implemented in the following steps: Step 1.1, System Layout: Install the lidar transmitting system at the observation location; determine the horizontal spacing between the lateral receiving system and the lidar transmitting system based on the required range resolution of the target detection area. D ; Step 1.2, Resolution Adjustment: Adjust the scanning cycle of the electrically adjustable pitch support 10 and the horizontal spacing distance of the lateral receiving system. D Set the spatial resolution of the lateral receiving system; Among them, the lateral receiving system can operate at any pitch angle. θ Distance resolution d z The calculation formula is as follows:

[0041] In the formula: D The horizontal distance between the lateral receiving system and the lidar transmitting system; dθ This is the receiving field of view angle of the side telescope 5; θ The scanning angle of the electrically adjustable pitch support 10; δ 1 represents the initial angle between the optical axis of the side telescope 5 and the horizontal plane; Step 1.3, Multi-system Expansion: Based on detection requirements, deploy several sets of lateral receiving systems along the optical path; the lateral receiving systems at closer locations are configured with a smaller horizontal distance. D To achieve high-resolution low-altitude detection, the lateral receiving system at a distance is configured with a large horizontal range. D To achieve high-resolution detection coverage at higher altitudes.

[0042] Step 2: Deploy the backscattering Raman lidar receiving system; Step 2 is implemented in the following steps: Step 2.1, Beam Alignment: Deploy the backscattering Raman scattering lidar receiving system so that the field of view of its backscattering telescope 4 coincides with the vertical laser beam emitted by the lidar transmitting system; Step 2.2, Shared Light Source Coordination: Ensure that the backscattering Raman scattering lidar receiving system and the side receiving system share the same pulsed laser emitted by the high-power laser 1 as the excitation source to achieve coordinated observation.

[0043] Step 3: Data Acquisition and Processing; Step 3 is implemented in the following steps: Step 3.1, Signal Acquisition: Control the high-power laser 1 to emit pulsed laser; use the first data acquisition system 11 of the lateral receiving system to acquire and store the lateral Raman scattering echo signal and the Mi-Rayleigh scattering echo signal; use the second data acquisition system 14 of the backscattering lidar receiving system to acquire and store the backscattering Raman scattering echo signal and the Mi-Rayleigh scattering echo signal. Step 3.2, the inversion of water vapor mixing ratio and atmospheric temperature, specifically: (1) Water vapor mixing ratio inversion: The atmospheric water vapor mixing ratio is calculated using the following formula. W(z) :

[0044] In the formula: z To detect altitude; C These are system calibration constants; P H (z) The intensity of the received water vapor Raman scattering signal; P N (z) The intensity of the received nitrogen Raman scattering signal; ΔT r This is the atmospheric differential transmittance correction function; Δf r The ratio of phase functions; λ H The Raman wavelength for water vapor; λ N The wavelength is the nitrogen Raman wavelength. (2) Atmospheric temperature inversion: using the ratio of pure rotational Raman scattering signals from high and low quantum number channels Q(z) Inverted atmospheric temperature T(z) :

[0045] In the formula: P Low (z) and P High (z) The values ​​represent the intensity of pure rotational Raman scattering signals with low and high quantum numbers obtained after spectral dispersion by the spectral dispersion system 13, respectively. A , B These are the system constants determined through calibration experiments; (3) Inversion of aerosol optical parameters: Using the detected Mie-Rayleigh scattering signal P MR (z) and nitrogen vibration Raman scattering signal PN (z) Calculate the extinction coefficient of aerosols. α aer (z) :

[0046] In the formula: λ 0 represents the emitted laser wavelength; λ N The wavelength is the nitrogen Raman wavelength. N(z) Atmospheric number density; α mol (z) Atmospheric extinction coefficient; k Wavelength index; Step 3.3, Data stitching and full height profile generation: Set the effective detection blind zone height of the backscattering Raman lidar to... h 1. Set the effective detection upper limit height of the lateral receiving system to: h 2, h 1< h 2. Construct a complete, blind-spot-free atmospheric parameter profile from the ground to upper atmosphere using the following stitching algorithm. G Total (z) :

[0047] In the formula: G L(z) These are atmospheric parameters such as temperature, water vapor mixing ratio, or aerosol extinction coefficient obtained by inversion based on data from the lateral receiving system. G B(z) These are atmospheric parameters obtained by inversion based on data from a backscattering lidar receiving system; w (z) The weighting function for the transition region has values ​​in the interval [ h 1 , h 2] The value changes linearly or nonlinearly from 0 to 1.

[0048] Example 1 The following is a detection experiment of a lateral scanning Raman scattering lidar receiving system with multiple lateral receiving systems, a lidar transmitting system, and a backscattering Raman scattering lidar receiving system (the number of lateral receiving systems in this experiment is 1).

[0049] Figure 6The results of Mie-Rayleigh scattering and Raman scattering echo signals acquired by a backscattering Raman lidar are presented. On the clear, cloudless day, the echo signals, after distance-squared correction, showed the following: no signal was detected in the 0-0.35 km altitude range (a detection blind zone); the signal gradually stabilized in the 0.35-0.87 km altitude range (a detection transition zone); and the signal tended to stabilize in the 0.87-4.00 km altitude range (a detection overlap zone). The Mie-Rayleigh scattering signal had the highest intensity, while the high- and low-quantum-number pure rotational Raman scattering signals, as well as the N2 and H2O vibrational Raman scattering signals, were significantly weaker than the Mie-Rayleigh scattering signal. With increasing detection altitude, all types of signals generally showed a decreasing trend with relatively small fluctuations. Specifically, the H2O vibrational Raman scattering signal exhibited slight continuous fluctuations in the 1.75–4.00 km altitude range, indicating the presence of water vapor accumulation in this layer; the N2 vibrational Raman scattering signal, however, consistently decayed steadily, indicating extremely stable atmospheric nitrogen concentration. The pure rotational Raman signals with high and low quantum numbers effectively suppressed Mie scattering crosstalk, and their intensity gradually decreased with increasing altitude, showing a certain correlation with atmospheric temperature changes.

[0050] In an experiment with a side-scanning Raman scattering lidar with multiple side-receiving systems, by optimizing the configuration function, a single side-receiving system can achieve different resolutions for the same atmospheric parameters at the same location. Figure 8 The results show that as the horizontal spacing D between the transceiver systems increases, the detection height also increases.

[0051] When the scattering angle varies within the range of 0°-170°, the change in D has a relatively small impact on the detection altitude, which is generally below 500 m. Furthermore, the dense distribution of detection points leads to a higher range resolution. However, when the scattering angle exceeds 170°, the impact of D on the detection altitude becomes more significant, and sparse detection points result in a lower resolution. Therefore, in practical applications, the lateral receiving system needs to optimize the range resolution configuration to improve the accuracy of atmospheric profile information.

[0052] To address the needs of near-surface atmospheric temperature and water vapor detection, two range resolution configuration schemes were designed: full-segment equidistant resolution and segmented equidistant resolution.

[0053] The experimental results of the full-segment equidistant resolution scheme show that when the horizontal distance D between the transceiver systems is 60 m, the lateral receiving system, with continuous elevation scanning from 0° to 87.4°, can achieve a maximum detection height of 1296 m at 37 sampling angles, while maintaining a distance resolution of 36 m, thus achieving stable detection of the complete vertical profile. Table 1 shows the detailed configuration parameters of this scheme during the scanning process.

[0054] Table 1

[0055] For the segmented equidistant resolution configuration scheme, when the horizontal distance D between the transceiver systems is 60m, the lateral receiving system achieves a detection height of 1332m through 41 preset elevation angles. Its scanning process can be divided into four stages: the first stage (0-72m) sets 11 sampling points with an elevation angle of 0°-50.2° and a resolution of 7.2m; the second stage (72-312m) includes 10 sampling points with an elevation angle of 50.2°-79.1° and a resolution of 24m; the third stage (312-732m) sets 10 sampling points with an elevation angle of 79.1°-85.3° and a resolution of 42m; and the fourth stage (732-1332m) sets 10 sampling points with an elevation angle of 85.3°-87.4° and a resolution of 60m. Table 2 lists the segmented equidistant resolution configuration scheme for the lateral scanning Raman scattering lidar. Compared to the equidistant resolution configuration across the entire segment, the segmented configuration offers significant advantages when probing the lower atmosphere. This configuration results in relatively smaller changes in the gimbal's elevation scanning angle when the side-mounted telescope receives scattered signals from the lower atmosphere, which is more conducive to the detailed detection of atmospheric temperature and water vapor.

[0056] Table 2

[0057] Figure 7 This graph shows the relationship between the scattering angle and the detection height when the horizontal distance D between the transceiver systems is 50 m, 60 m, 70 m, and 80 m. It can be seen from the graph that the detection height increases with the increase of the horizontal distance D between the transceiver systems. Since the detection height z is related to the scattering angle... θ The tangent of the scattering angle is inversely proportional to the range resolution. When the scattering angle varies between 0° and 170°, the change in the horizontal distance D between the transceiver systems has a relatively small impact on the detection height of the side-scanning Raman scattering lidar, with detection heights all below 500 m. Furthermore, the excessively dense detection points result in a low range resolution. However, when the scattering angle exceeds 170°, the horizontal distance D between the transceiver systems has a more significant impact on the detection height as the scattering angle gradually increases. In this range, the detection points are relatively sparse, leading to an excessively high range resolution. Therefore, the range resolution configuration of the side-scanning Raman scattering lidar needs to be optimized in experimental detection to improve the vertical profile accuracy of atmospheric state information.

[0058] Figure 8The figure shows the data profile and temperature detection results of a side-scanning Raman scattering lidar with a multi-side receiving system using a full-segment equidistant resolution configuration. The figure shows the vertical profile of the near-surface atmospheric temperature obtained by inversion. It can be seen that the near-surface atmospheric temperature detected by the side-scanning Raman scattering lidar has good consistency with the radiosonde data. The presence of temperature inversion layers can be clearly observed in the 0-54 m and 480-840 m regions.

[0059] Figure 9 This figure presents the data profile and atmospheric temperature detection results obtained by a lateral scanning Raman scattering lidar with a multi-lateral receiving system using a segmented equidistant resolution configuration. The figure shows the vertical profile of near-surface atmospheric temperature obtained through inversion, compared with radiosonde data from the same day for verification. The results show that there are small, continuous temperature fluctuations in the 0-72 m range near the surface, and temperature inversion layers appear in the 0-156 m and above 1100 m regions. These characteristics show good consistency with the radiosonde data, verifying the accuracy and reliability of the inversion method.

[0060] Figure 10 The figure presents the data profile and atmospheric temperature detection results of a lateral scanning Raman scattering lidar with a multi-lateral receiving system, using a full-segment equidistant resolution configuration. The figure shows the vertical distribution profile of the near-surface water vapor mixing ratio obtained through inversion, revealing a clear spatial variation of atmospheric water vapor with altitude. It can be seen that the water vapor mixing ratio is relatively stable between 4.10 and 4.13 g / kg in the altitude range below 596 m, due to the similar attenuation trends of both N2 vibrational Raman scattering and H2O vibrational Raman scattering signals in this region. However, a significant water vapor accumulation layer exists in the altitude range of 600-1200 m, where the water vapor mixing ratio reaches 4.22 g / kg.

[0061] Figure 11 The figure shows the data profile and atmospheric temperature detection results obtained by a segmented equidistant resolution configuration scheme for a lateral scanning Raman scattering lidar with a multi-lateral receiving system. The figure also displays the vertical distribution profile of the near-surface water vapor mixing ratio obtained through inversion.

[0062] Figure 12 The results of atmospheric temperature inversion obtained by joint detection of a lateral scanning Raman scattering lidar with a multi-lateral receiving system and a backscattering Raman scattering lidar are presented.

[0063] To achieve blind-zone-free detection from the near-surface to the upper atmosphere, atmospheric temperature and water vapor mixing ratio obtained by inverting the Raman scattering signals detected by backscattering lidar and Raman scattering signals detected by lateral scanning Raman scattering lidar are stitched together. This minimizes the detection errors of near-surface atmospheric parameters caused by the existence of detection blind zones and detection transition zones in the backscattering lidar. The data stitching algorithm for atmospheric temperature and water vapor mixing ratio from the lateral combined backscattering lidar can be expressed as follows:

[0064] In the formula, G L ( T z , W z , z) and G B ( T z , W z (z) represents the atmospheric temperature and water vapor mixing ratio obtained by the side-scanning Raman scattering lidar and the back-scanning Raman scattering lidar, respectively. The range-squared correction signal from the back-scanning Raman scattering lidar is used to determine... h The height of 1 is determined based on the system settings of the side-scanning Raman scattering lidar. h The altitude is 2. In this joint exploration, h 1 is 0.87 km. h 2 is 1.37 km.

[0065] To effectively address the detection blind zone and transition zone issues of backscattering Raman lidar, a side-scanning Raman scattering lidar with a multi-lateral receiving system was used simultaneously to scan and detect the near-surface atmosphere. The experiment employed a continuous equidistant resolution configuration with a range resolution of 36 m, enabling the detection of atmospheric temperature, water vapor, and aerosol extinction within an altitude range of 0–1.37 km. Figure 13 shows the atmospheric humidity inversion results obtained from the joint detection by the side-scanning Raman scattering lidar with a multi-lateral receiving system and the backscattering Raman lidar. Figure 13 The results show that the blind zone and transition zone of the backscattering Raman lidar are 0-0.87 km, exhibiting a significant deviation in water vapor mixture ratio compared to the radiosonde. In contrast, the side-scanning Raman lidar can cover and accurately measure the water vapor mixture ratio within the 0-1.37 km altitude range, showing good consistency with the radiosonde. The combined side-scanning and backscattering Raman lidar system can detect the water vapor mixture ratio within the 0-4.00 km altitude range, with a statistical error of less than 0.5 g / kg.

[0066] In the above experiments, the lateral scanning Raman scattering lidar and the backscattering Raman scattering lidar with multi-lateral receiving systems used segmented and full-segment equidistant range resolution configuration parameters to measure atmospheric parameters. By adjusting the range resolution, the complex structural details of the stable boundary layer at night can be captured more accurately. When encountering complex and changeable weather, the number, interval and scanning strategy of the lateral receiving systems can be flexibly adjusted to achieve continuous profile detection of the entire atmosphere within the stable boundary layer at night with meter-level range resolution.

[0067] In the aforementioned process, multi-device and multi-system collaborative control and acquisition were carried out, and a multimodal normalized data inversion algorithm was constructed to achieve temporal and spatial matching of the entire layer of observation data. Blind-spot-free, high spatiotemporal resolution profile data of temperature, water vapor, and aerosols from the surface to 3 km were obtained. The thermal structure of the stable boundary layer, material transport and transmission processes, and the variation patterns of surface pollutants were analyzed. Combined with near-surface atmospheric radiation, relevant hydrothermal observation data, and large-scale reanalysis data, the relationship between surface radiation, local circulation, and surface pollutant variations was analyzed, and the impact mechanism of the evolution of the stable boundary layer structure on pollutant transport and transmission was explored in depth.

[0068] Example 2 Blind-zone-free laser remote sensing systems for stable boundary layer thermodynamic material structures, such as Figure 1-4 As shown, it includes a lateral scanning Raman scattering lidar receiving system with multiple lateral receiving systems, a lidar transmitting system, and a backscattering Raman scattering lidar receiving system; Example 3 Blind-zone-free laser remote sensing systems for stable boundary layer thermodynamic material structures, such as Figure 1-4 As shown, it includes a lateral scanning Raman scattering lidar receiving system with multiple lateral receiving systems, a lidar transmitting system, and a backscattering Raman scattering lidar receiving system; A lateral scanning Raman scattering lidar receiving system with multiple lateral receiving systems includes several lateral receiving systems; The lateral receiving system is used to receive lateral Raman scattering echo signals and Mi-Rayleigh scattering echo signals from nitrogen, water vapor and aerosols in the atmosphere, and transmit the received signals to the data acquisition system for acquisition and storage. The backscattering lidar receiving system is used to receive backscattering echo signals of nitrogen and water vapor in the upper atmosphere, and transmit the received signals to the data acquisition system for acquisition and storage. Several lateral receiving systems and a backscattering Raman scattering lidar receiving system share the lidar transmitting system as the excitation light source.

[0069] Example 4 Blind-zone-free laser remote sensing systems for stable boundary layer thermodynamic material structures, such as Figure 1-4 As shown, it includes a lateral scanning Raman scattering lidar receiving system with multiple lateral receiving systems, a lidar transmitting system, and a backscattering Raman scattering lidar receiving system; A lateral scanning Raman scattering lidar receiving system with multiple lateral receiving systems includes several lateral receiving systems; The lateral receiving system is used to receive lateral Raman scattering echo signals and Mi-Rayleigh scattering echo signals from nitrogen, water vapor and aerosols in the atmosphere, and transmit the received signals to the data acquisition system for acquisition and storage. The backscattering lidar receiving system is used to receive backscattering echo signals of nitrogen and water vapor in the upper atmosphere, and transmit the received signals to the data acquisition system for acquisition and storage. Several lateral receiving systems and a backscattering Raman scattering lidar receiving system share the lidar transmitting system as the excitation light source.

[0070] The lateral receiving system includes an electrically adjustable pitch support 10 and a first data acquisition system 11. Several sets of lateral telescope assemblies are installed on the electrically adjustable pitch support 10. The electrically adjustable pitch support 10 is used to drive the lateral telescope assemblies to perform pitch scanning in order to change the detection field of view. Each side-view telescope assembly includes a side-view telescope 5, and after the light outlet of the side-view telescope 5, a first collimating lens 6, a first filter 7, a first focusing lens 8 and a first photomultiplier tube 9 are connected in sequence via optical path. The side-facing telescope 5 is used to receive the side-facing Raman scattering echo signal generated by the interaction of the pulsed laser emitted by the lidar transmitting system with the atmosphere. After being received by the side-facing telescope 5, the side-facing Raman scattering echo signal is incident on the first collimating lens 6. The first collimating lens 6 collimates the diverging beam into a parallel beam and then directs it onto the first filter 7. The first filter 7 performs spectral dispersion processing on the incident parallel beam, allowing only the Raman scattering light signal with a preset center wavelength to pass through. The light signal passing through the first filter 7 is focused and converged by the first focusing lens 8 and then enters the first photomultiplier tube 9. The first photomultiplier tube 9 is used to detect weak light signals and convert them into electrical signals. The first photomultiplier tube 9 is connected to the first data acquisition system 11, which is used to perform high-speed acquisition and storage of the electrical signals.

[0071] Example 5 Blind-zone-free laser remote sensing systems for stable boundary layer thermodynamic material structures, such as Figure 1-4 As shown, it includes a lateral scanning Raman scattering lidar receiving system with multiple lateral receiving systems, a lidar transmitting system, and a backscattering Raman scattering lidar receiving system; A lateral scanning Raman scattering lidar receiving system with multiple lateral receiving systems includes several lateral receiving systems; The lateral receiving system is used to receive lateral Raman scattering echo signals and Mi-Rayleigh scattering echo signals from nitrogen, water vapor and aerosols in the atmosphere, and transmit the received signals to the data acquisition system for acquisition and storage. The backscattering lidar receiving system is used to receive backscattering echo signals of nitrogen and water vapor in the upper atmosphere, and transmit the received signals to the data acquisition system for acquisition and storage. Several lateral receiving systems and a backscattering Raman scattering lidar receiving system share the lidar transmitting system as the excitation light source.

[0072] The lateral receiving system includes an electrically adjustable pitch support 10 and a first data acquisition system 11. Several sets of lateral telescope assemblies are installed on the electrically adjustable pitch support 10. The electrically adjustable pitch support 10 is used to drive the lateral telescope assemblies to perform pitch scanning in order to change the detection field of view. Each side-view telescope assembly includes a side-view telescope 5, and after the light outlet of the side-view telescope 5, a first collimating lens 6, a first filter 7, a first focusing lens 8 and a first photomultiplier tube 9 are connected in sequence via optical path. The side-facing telescope 5 is used to receive the side-facing Raman scattering echo signal generated by the interaction of the pulsed laser emitted by the lidar transmitting system with the atmosphere. After being received by the side-facing telescope 5, the side-facing Raman scattering echo signal is incident on the first collimating lens 6. The first collimating lens 6 collimates the diverging beam into a parallel beam and then directs it onto the first filter 7. The first filter 7 performs spectral dispersion processing on the incident parallel beam, allowing only the Raman scattering light signal with a preset center wavelength to pass through. The light signal passing through the first filter 7 is focused and converged by the first focusing lens 8 and then enters the first photomultiplier tube 9. The first photomultiplier tube 9 is used to detect weak light signals and convert them into electrical signals. The first photomultiplier tube 9 is connected to the first data acquisition system 11, which is used to perform high-speed acquisition and storage of the electrical signals.

[0073] The lidar transmitting system includes a high-power laser 1, a laser beam expander 2, and a reflector 3 connected in sequence via optical paths; the reflector 3 is set at 45° relative to the horizontal plane. A high-power laser 1 is used to emit a horizontal pulsed laser of a specific wavelength. The horizontal pulsed laser is collimated and expanded by a laser beam expander 2 and then incident on a reflector 3. The reflector 3 reflects the incident horizontal laser so that it is directed perpendicularly toward the atmosphere. The pulsed laser directed perpendicularly toward the atmosphere serves as a shared excitation source for the lateral receiving system and the backscattering Raman scattering lidar receiving system. The pulsed laser interacts with nitrogen and water vapor in the atmosphere to generate Raman scattering signals, which are received by the lateral receiving system and the backscattering Raman scattering lidar receiving system, respectively.

[0074] Example 6 Blind-zone-free laser remote sensing systems for stable boundary layer thermodynamic material structures, such as Figure 1-4 As shown, it includes a lateral scanning Raman scattering lidar receiving system with multiple lateral receiving systems, a lidar transmitting system, and a backscattering Raman scattering lidar receiving system; A lateral scanning Raman scattering lidar receiving system with multiple lateral receiving systems includes several lateral receiving systems; The lateral receiving system is used to receive lateral Raman scattering echo signals and Mi-Rayleigh scattering echo signals from nitrogen, water vapor and aerosols in the atmosphere, and transmit the received signals to the data acquisition system for acquisition and storage. The backscattering lidar receiving system is used to receive backscattering echo signals of nitrogen and water vapor in the upper atmosphere, and transmit the received signals to the data acquisition system for acquisition and storage. Several lateral receiving systems and a backscattering Raman scattering lidar receiving system share the lidar transmitting system as the excitation light source.

[0075] The lateral receiving system includes an electrically adjustable pitch support 10 and a first data acquisition system 11. Several sets of lateral telescope assemblies are installed on the electrically adjustable pitch support 10. The electrically adjustable pitch support 10 is used to drive the lateral telescope assemblies to perform pitch scanning in order to change the detection field of view. Each side-view telescope assembly includes a side-view telescope 5, and after the light outlet of the side-view telescope 5, a first collimating lens 6, a first filter 7, a first focusing lens 8 and a first photomultiplier tube 9 are connected in sequence via optical path. The side-facing telescope 5 is used to receive the side-facing Raman scattering echo signal generated by the interaction of the pulsed laser emitted by the lidar transmitting system with the atmosphere. After being received by the side-facing telescope 5, the side-facing Raman scattering echo signal is incident on the first collimating lens 6. The first collimating lens 6 collimates the diverging beam into a parallel beam and then directs it onto the first filter 7. The first filter 7 performs spectral dispersion processing on the incident parallel beam, allowing only the Raman scattering light signal with a preset center wavelength to pass through. The light signal passing through the first filter 7 is focused and converged by the first focusing lens 8 and then enters the first photomultiplier tube 9. The first photomultiplier tube 9 is used to detect weak light signals and convert them into electrical signals. The first photomultiplier tube 9 is connected to the first data acquisition system 11, which is used to perform high-speed acquisition and storage of the electrical signals.

[0076] The lidar transmitting system includes a high-power laser 1, a laser beam expander 2, and a reflector 3 connected in sequence via optical paths; the reflector 3 is set at 45° relative to the horizontal plane. A high-power laser 1 is used to emit a horizontal pulsed laser of a specific wavelength. The horizontal pulsed laser is collimated and expanded by a laser beam expander 2 and then incident on a reflector 3. The reflector 3 reflects the incident horizontal laser so that it is directed perpendicularly toward the atmosphere. The pulsed laser directed perpendicularly toward the atmosphere serves as a shared excitation source for the lateral receiving system and the backscattering Raman scattering lidar receiving system. The pulsed laser interacts with nitrogen and water vapor in the atmosphere to generate Raman scattering signals, which are received by the lateral receiving system and the backscattering Raman scattering lidar receiving system, respectively.

[0077] The backscattering Raman lidar receiving system includes a backscattering telescope 4, a second collimating lens 15, a prism 12, and a spectral splitting system 13 connected in sequence via optical paths; it also includes a second data acquisition system 14 connected to the spectral splitting system 13. The back-scattering telescope 4 is used to receive the back-scattering Raman echo signal generated by the interaction of the pulsed laser emitted by the lidar transmitting system with the atmosphere. After being received by the back-scattering telescope 4, the back-scattering Raman echo signal is collimated by the second collimating lens 15 and incident on the spectral splitting system 13 under the refracting and guiding action of the prism 12. The spectral splitting system 13 is used to perform fine spectral splitting and photoelectric conversion on the incident light signal. The second data acquisition system 14 is used to acquire and store the converted electrical signal.

Claims

1. A blind-zone-free laser remote sensing system for stable boundary layer thermodynamic material structures, characterized in that, It includes a lateral scanning Raman scattering lidar receiving system with multiple lateral receiving systems, a lidar transmitting system, and a backscattering Raman scattering lidar receiving system.

2. The blind-zone-free laser remote sensing system for stable boundary layer thermodynamic material structures according to claim 1, characterized in that, The side-scanning Raman scattering lidar receiving system with multiple side-scanning receiving systems includes several side-scanning receiving systems; The lateral receiving system is used to receive lateral Raman scattering echo signals and Mi-Rayleigh scattering echo signals from nitrogen, water vapor and aerosols in the atmosphere, and transmit the received signals to the data acquisition system for acquisition and storage. The backscattering lidar receiving system is used to receive backscattering echo signals of nitrogen and water vapor in the upper atmosphere, and transmit the received signals to the data acquisition system for acquisition and storage. Several lateral receiving systems and a backscattering Raman scattering lidar receiving system share the lidar transmitting system as the excitation light source.

3. The blind-zone-free laser remote sensing system for stable boundary layer thermodynamic material structures according to claim 1, characterized in that, The lateral receiving system includes an electrically adjustable pitch support (10) and a first data acquisition system (11). Several sets of lateral telescope assemblies are installed on the electrically adjustable pitch support (10). The electrically adjustable pitch support (10) is used to drive the lateral telescope assemblies to perform pitch scanning in order to change the detection field of view. Each side telescope assembly includes a side telescope (5), and the light output port of the side telescope (5) is connected in sequence to a first collimating lens (6), a first filter (7), a first focusing lens (8) and a first photomultiplier tube (9). The side telescope (5) is used to receive the side Raman scattering echo signal generated by the interaction between the pulsed laser emitted by the lidar transmitting system and the atmosphere. After the side Raman scattering echo signal is received by the side telescope (5), it is incident on the first collimating lens (6). The first collimating lens (6) collimates the diverging beam into a parallel beam and then directs it onto the first filter (7). The first filter (7) performs spectral dispersion processing on the incident parallel beam and only allows the Raman scattering light signal with a preset center wavelength to pass through. The light signal passing through the first filter (7) is focused and converged by the first focusing lens (8) and then enters the first photomultiplier tube (9). The first photomultiplier tube (9) is used to detect the light signal and convert it into an electrical signal. The first photomultiplier tube (9) is connected to the first data acquisition system (11). The first data acquisition system (11) is used to perform high-speed acquisition and storage of the electrical signal.

4. The blind-zone-free laser remote sensing system for stable boundary layer thermodynamic material structures according to claim 3, characterized in that, The lidar transmitting system includes a high-power laser (1), a laser beam expander (2), and a reflector (3) connected in sequence by optical paths; the reflector (3) is set at 45° relative to the horizontal plane; The high-power laser (1) is used to emit horizontal pulsed laser. The horizontal pulsed laser is collimated and expanded by the laser beam expander (2) and then incident on the reflector (3). The reflector (3) reflects the incident horizontal laser so that it is directed vertically toward the atmosphere.

5. The blind-zone-free laser remote sensing system for stable boundary layer thermodynamic material structures according to claim 4, characterized in that, The backscattering Raman scattering lidar receiving system includes a backscattering telescope (4), a second collimating lens (15), a prism (12), and a spectral splitting system (13) connected in sequence via optical paths; it also includes a second data acquisition system (14) connected to the spectral splitting system (13). The back-facing telescope (4) is used to receive the back-Raman scattering echo signal generated by the interaction between the pulsed laser emitted by the lidar transmitting system and the atmosphere. After being received by the back-facing telescope (4), the back-Raman scattering echo signal is collimated by the second collimating lens (15) and incident on the spectral splitting system (13) under the refracting and guiding action of the prism (12). The spectral splitting system (13) is used to perform fine spectral splitting and photoelectric conversion on the incident light signal. The second data acquisition system (14) is used to acquire and store the converted electrical signal.

6. The blind-zone-free laser remote sensing system for stable boundary layer thermodynamic material structures according to claim 5, characterized in that, The spectral splitting system (13) includes a first beam splitting cube (16), which is used to split the incident beam after it has been refracted by the prism (12) into a first beam and a second beam that are perpendicular to each other. A second beam splitter (17) is provided on the optical path of the first beam, which splits the first beam into a third beam and a fourth beam that are perpendicular to each other. On the optical path of the third beam, a second filter (20), a second focusing lens (25) and a second photomultiplier tube (30) are arranged in order from near to far from the second beam splitter (17). On the optical path of the fourth beam, a sixth filter (24), a sixth focusing lens (29) and a sixth photomultiplier tube (34) are arranged in order from near to far from the second beam splitter (17). A third beam splitter (18) is provided on the optical path of the second beam, which splits the second beam into a fifth beam and a sixth beam that are perpendicular to each other. On the optical path of the sixth beam, a third filter (21), a third focusing lens (26), and a third photomultiplier tube (31) are arranged in order from near to far from the third beam splitter (18). A fourth beam splitter (19) is provided on the optical path of the fifth beam, which splits the fifth beam into a seventh beam and an eighth beam that are perpendicular to each other. On the optical path of the seventh beam, a fifth filter (23), a fifth focusing lens (28), and a fifth photomultiplier tube (33) are arranged in order from near to far from the fourth beam splitter (19). On the optical path of the eighth beam, a fourth filter (22), a fourth focusing lens (27), and a fourth photomultiplier tube (32) are arranged in order from near to far from the fourth beam splitter (19). The second photomultiplier tube (30), the third photomultiplier tube (31), the fourth photomultiplier tube (32), the fifth photomultiplier tube (33) and the sixth photomultiplier tube (34) are all connected to the second data acquisition system (14).

7. A blind-zone-free laser remote sensing method for stabilizing the thermal material structure of the boundary layer, characterized in that, The system described in any one of claims 1-6 is specifically as follows: Step 1: Deploy a side-scanning Raman scattering lidar receiving system with multiple side-facing receiving systems; Step 2: Deploy the backscattering Raman lidar receiving system; Step 3: Data Acquisition and Processing.

8. The blind-zone-free laser remote sensing method for stable boundary layer thermodynamic material structures according to claim 7, characterized in that, Step 1 is implemented in the following steps: Step 1.1, System Layout: Install the lidar transmitting system at the observation location; determine the horizontal spacing between the lateral receiving system and the lidar transmitting system based on the required range resolution of the target detection area. D ; Step 1.2, Resolution Adjustment: Adjust the scanning cycle of the electrically adjustable pitch support (10) and the horizontal spacing distance of the lateral receiving system. D Set the spatial resolution of the lateral receiving system; Among them, the lateral receiving system can operate at any pitch angle. θ Distance resolution d z The calculation formula is as follows: In the formula: D The horizontal distance between the lateral receiving system and the lidar transmitting system; dθ The receiving field of view of the side telescope (5); θ The scanning angle of the electrically adjustable pitch support (10); δ 1 represents the initial angle between the optical axis of the side telescope (5) and the horizontal plane; Step 1.3, Multi-system expansion: Deploy several sets of lateral receiving systems along the optical path according to the detection requirements.

9. The blind-zone-free laser remote sensing method for stable boundary layer thermodynamic material structures according to claim 7, characterized in that, Step 2 is implemented in the following steps: Step 2.1, Beam Alignment: Deploy the backscattering Raman scattering lidar receiving system so that the field of view of its backscattering telescope (4) coincides with the vertical laser beam emitted by the lidar transmitting system; Step 2.2, Shared Light Source Coordination: Ensure that the backscattering Raman scattering lidar receiving system and the side receiving system share the same pulsed laser emitted by the high-power laser (1) as the excitation source to achieve coordinated observation.

10. The blind-zone-free laser remote sensing method for stable boundary layer thermodynamic material structures according to claim 7, characterized in that, Step 3 is implemented in the following steps: Step 3.1, Signal Acquisition: Control the high-power laser (1) to emit pulsed laser; use the first data acquisition system (11) of the lateral receiving system to acquire and store the lateral Raman scattering echo signal and the Mi-Rayleigh scattering echo signal; use the second data acquisition system (14) of the backscattering lidar receiving system to acquire and store the backscattering Raman scattering echo signal and the Mi-Rayleigh scattering echo signal; Step 3.2, the inversion of water vapor mixing ratio and atmospheric temperature, specifically: (1) Water vapor mixing ratio inversion: The atmospheric water vapor mixing ratio is calculated using the following formula. W(z) : In the formula: z To detect altitude; C These are system calibration constants; P H (z) The intensity of the received water vapor Raman scattering signal; P N (z) The intensity of the received nitrogen Raman scattering signal; ΔT r This is the atmospheric differential transmittance correction function; Δf r The ratio of phase functions; λ H The Raman wavelength for water vapor; λ N The wavelength of nitrogen Raman gas; (2) Atmospheric temperature inversion: using the ratio of pure rotational Raman scattering signals from high and low quantum number channels Q(z) Inverted atmospheric temperature T(z) : In the formula: P Low (z) and P High (z) The values ​​are the intensity of low quantum number and high quantum number pure rotational Raman scattering signals obtained after spectral dispersion by the spectral dispersion system (13); A , B These are the system constants determined through calibration experiments; (3) Inversion of aerosol optical parameters: Using the detected Mie-Rayleigh scattering signal P MR (z) and nitrogen vibration Raman scattering signal P N (z) Calculate the extinction coefficient of aerosols. α aer (z) : In the formula: λ 0 represents the emitted laser wavelength; λ N The wavelength of nitrogen Raman gas; N(z) Atmospheric number density; α mol (z) Atmospheric extinction coefficient; k Wavelength index; Step 3.3, Data stitching and full height profile generation: Set the effective detection blind zone height of the backscattering Raman lidar to... h 1. Set the effective detection upper limit height of the lateral receiving system to: h 2, h 1< h 2. Construct a complete, blind-spot-free atmospheric parameter profile from the ground to upper atmosphere using the following stitching algorithm. G Total (z) : In the formula: G L(z) These are atmospheric parameters obtained by inversion based on data from the lateral receiving system; G B(z) These are atmospheric parameters obtained by inversion based on data from a backscattering lidar receiving system; w(z) The weighting function for the transition region has values ​​in the interval [ h 1 , h 2] The value changes linearly or nonlinearly from 0 to 1.

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