Vehicle-mounted mobile detection middle and upper atmosphere detection laser radar and correction method

Abstract

The invention discloses a vehicle-mounted mobile detection middle and upper atmosphere detection laser radar, which comprises a vehicle-mounted square cabin, and a reflector attitude monitoring module, a reflector attitude adjusting motor, a telescope attitude monitoring module, a telescope attitude adjusting motor, a photoelectric detector and a rotatable optical platform which are arranged in the vehicle-mounted square cabin, the device can be used as a fixed station for observation and can also be used as a mobile station for observation, and regional continuous observation can be realized, so that the spatial and temporal distribution characteristics of middle and upper atmosphere observation data are greatly improved; the invention further discloses a correction method of the vehicle-mounted mobile detection middle and upper atmosphere detection laser radar, coarse adjustment and fine adjustment are carried out on the reflector and the telescope by monitoring the angle deviation value of the reflector and the telescope and the number of echo photons, real-time adjustment can be carried out on receiving and transmitting matching in the transportation and movement process, and the correction accuracy is improved. Therefore, the adverse effect caused by vibration in the vehicle-mounted mobile observation process is overcome.

Description

Technical Field

[0001] This invention relates to a lidar for detecting the middle and upper atmosphere, and more particularly to a vehicle-mounted mobile lidar for detecting the middle and upper atmosphere, as well as a calibration method for the vehicle-mounted mobile lidar for detecting the middle and upper atmosphere. Background Technology

[0002] Atmospheric lidar obtains information such as atmospheric wind field, temperature, and density by interacting with the atmosphere using pulsed lasers of specific wavelengths. It plays an increasingly important role in weather forecasting, scientific research, and space activity support, while simultaneously demanding higher levels of timeliness and spatial distribution in its detection capabilities. Currently, ground-based mid-to-upper atmosphere detection primarily relies on fixed observation stations, limiting its coverage to specific geographical areas. While vehicle-mounted observation platforms have emerged recently, they merely transfer equipment from one location to another. The equipment cannot function during transport, and extensive preparations are required before and after arrival at the destination, making continuous regional observation impossible. Summary of the Invention

[0003] The purpose of this invention is to address the problems existing in the prior art by proposing a vehicle-mounted mobile lidar for detecting the upper atmosphere, and also to provide a calibration method for the vehicle-mounted mobile lidar for detecting the upper atmosphere.

[0004] The above-mentioned objectives of the present invention are achieved by the following technical means: A vehicle-mounted mobile lidar for detecting the upper atmosphere includes a laser pulse generator, a reflector, and a telescope. It also includes a vehicle-mounted cabin, a reflector attitude monitoring module, a reflector attitude adjustment motor, a telescope attitude monitoring module, a telescope attitude adjustment motor, a photodetector, and a rotatable optical platform. The vehicle-mounted cabin has a skylight, and the rotatable optical platform is fixedly installed inside. The laser pulse generator outputs a laser beam onto the reflector. The laser pulse generator, reflector, telescope, reflector attitude monitoring module, reflector attitude adjustment motor, telescope attitude monitoring module, and telescope attitude adjustment motor are all mounted on the rotatable optical platform. The receiving plane of the telescope is parallel to the surface of the rotatable optical platform. The emitted laser beam is reflected by the reflector and then directed vertically towards the sky along the surface of the rotatable optical platform. The reflector attitude adjustment motor and reflector attitude monitoring module are both connected to the reflector, and the telescope attitude monitoring module and telescope attitude adjustment motor are both connected to the telescope. The telescope's output port is also equipped with an echo signal processing module, which is connected to the photodetector.

[0005] As described above, the reflector attitude monitoring module is used to collect the attitude position information α1 of the reflector. The attitude position information α1 of the reflector includes the first angle α11 and the second angle α12 of the reflector. The reflector attitude adjustment motor is used to adjust the first angle α11 and the second angle α12 of the reflector. The first angle α11 is the angle between the mirror normal of the reflector and the X-axis direction of the rotatable optical platform, and the second angle α12 is the angle between the mirror normal of the reflector and the Y-axis direction of the rotatable optical platform. The telescope attitude monitoring module is used to collect the telescope's attitude position information α2. The telescope's attitude position information α2 includes the telescope's third angle α21 and fourth angle α22. The telescope attitude adjustment motor is used to adjust the telescope's third angle α21 and fourth angle α22. The third angle α21 is the angle between the telescope's field of view direction and the X-axis direction of the rotatable optical platform, and the fourth angle α22 is the angle between the telescope's field of view direction and the Y-axis direction of the rotatable optical platform.

[0006] It also includes a data processing and control module, which includes an FPGA module and a Beidou navigation module. The FPGA module is connected to the laser pulse generating device, the reflector attitude monitoring module, the reflector attitude adjustment motor, the telescope attitude monitoring module, the telescope attitude adjustment motor, the rotatable optical platform, and the photodetector. The data processing and control module also includes a BeiDou navigation module, which provides real-time vehicle location information.

[0007] As described above, the FPGA module performs coarse adjustment of the reflector and telescope based on the attitude position information: the reflector attitude monitoring module collects the real-time attitude position information of the reflector and sends it to the FPGA module. The FPGA module calculates the deviation value of the first angle and the deviation value of the second angle based on the optimal attitude position information of the reflector, and corrects the reflector to the optimal attitude position through the reflector attitude adjustment motor. The telescope attitude monitoring module collects the real-time attitude position information of the telescope and sends it to the FPGA module. The FPGA module calculates the deviation values ​​of the third angle and the fourth angle based on the telescope's optimal attitude position information, and corrects the telescope to the optimal attitude position through the telescope attitude adjustment motor. The optimal attitude and position information for the mirror and telescope are respectively the attitude and position information of the mirror and telescope when the number of echo photons reaches its maximum value in a stationary state.

[0008] As described above, the echo signal processing module is used to filter out background noise from the original echo, which is then converted into an electrical signal by a photodetector and sent to the FPGA module for acquisition. The FPGA module fine-tunes the first angle α11 and the second angle α12 of the reflector and the third angle α21 and the fourth angle α22 of the telescope according to the reference value L, the threshold value δ, and the real-time measured echo photon number N0. When |L-N0|≤δ, the fine-tuning is completed.

[0009] As described above, the laser pulse generating device includes a pulsed laser generator and an emitting optical path. The pulsed laser generator is connected to an FPGA module, and the FPGA module controls the turning the pulsed laser generator on and off. The emitted laser generated by the pulsed laser generator is transmitted to the reflector after being adjusted by the emitting optical path.

[0010] It also includes a weather monitoring module, a solar panel, a battery-powered module, and a mains power supply module. The FPGA module is also connected to the weather monitoring module, the solar panel, the battery-powered module, and the mains power supply module.

[0011] A calibration method for a vehicle-mounted mobile lidar for detecting the upper atmosphere, utilizing the aforementioned vehicle-mounted mobile lidar for detecting the upper atmosphere, includes the following steps: Step 1: The FPGA module obtains the current weather status from the weather monitoring module. If the weather is in the set suitable weather conditions for measurement, the pulse laser generator is turned on to generate a horizontal laser. After passing through the emission adjustment optical path, the laser reaches the center of the reflector and is directed vertically towards the sky along the surface of the rotatable platform. The echo signal falls into the receiving field of view of the telescope. The echo signal processing module filters the echo signal to remove the interference of background light. Then, it is converted into an electrical signal by the photoelectric converter and transmitted to the FPGA module, thus completing the detection of the echo signal. Step 2: Collect and record the optimal attitude position information of the reflector and the telescope when the echo photon count reaches its maximum value while the vehicle is stationary; and obtain historical observation data of the echo photon count at different altitudes under the current weather conditions as a reference value L, and set a threshold value δ. Step 3: During vehicle operation, the real-time attitude and position information of the reflector and the telescope are monitored by the attitude monitoring module and the telescope attitude monitoring module, respectively, and then sent to the FPGA module. Step 4: Perform coarse adjustment of the reflector and telescope: The FPGA module calculates the deviation of the reflector's angle based on the reflector's real-time attitude position information and the reflector's optimal attitude position information, and corrects the reflector's attitude according to the deviation value through the reflector attitude adjustment motor. The FPGA module calculates the deviation of the telescope's angle based on the telescope's real-time attitude position information and the telescope's optimal attitude position information, and corrects the telescope's attitude according to the deviation value through the telescope attitude adjustment motor. Step 5: Fine-tune the reflector: Adjust the reflector by measuring the echo photon count in real time until the difference between the real-time measured echo photon count N0 and the reference value L is less than the threshold value δ. Stop the adjustment and record the current measured value of the echo photon count as the final measured value of the echo photon count. If adjusting the reflector fails to make the difference between the real-time measured echo photon count N0 and the reference value L less than the threshold value δ, then keep the reflector at the attitude position where N0 is at its maximum value, and then fine-tune the telescope until the difference between the real-time measured echo photon count N0 and the reference value L is less than the threshold value δ. Then stop adjusting and record the current measured value of the echo photon count as the final measured value of the echo photon count. Step 6: The FPGA module performs real-time inversion of the final measured value of the echo photon number, obtains atmospheric wind field, temperature and density data at the current location, and obtains real-time location information from the Beidou navigation module to plot continuous atmospheric wind field, temperature and density distribution curves. Step 7: The initial position of the optical platform is horizontal. When it is necessary to measure parameters in other directions, the angle between the rotatable optical platform and the horizontal plane is adjusted by the FPGA module. Then, steps 1 to 6 are repeated to draw continuous atmospheric wind field, temperature and density distribution curves in other directions.

[0012] As described above, step 5, the fine-tuning of the reflector, specifically includes the following process: First, keep the telescope's attitude and position and the second angle α12 unchanged. Adjust the first angle α11 by changing the difference between the real-time measured echo photon number N0 and the reference value L until the real-time measured echo photon number N0 no longer changes. The adjustment of the first angle α11 is then completed, and the adjustment of the second angle α12 is performed. Then, keeping the telescope's attitude and the first angle α11 unchanged, the second angle α12 is adjusted by the change in the difference between the real-time measured echo photon number N0 and the reference value L, until the difference between the real-time measured echo photon number N0 and the reference value L is less than the threshold value δ, at which point the adjustment is stopped, and the fine adjustment of the reflector is completed. Step 5, the fine-tuning of the reflector, specifically includes the following processes: First, keep the attitude and position of the reflector and the fourth angle α22 unchanged. Adjust the third angle α21 by the change of the difference between the real-time measured echo photon number N0 and the reference value L until the real-time measured echo photon number N0 no longer changes. The adjustment of the third angle α21 is completed, and the adjustment of the fourth angle α22 is performed. Then, keeping the attitude and position of the reflector and the third angle α21 unchanged, the fourth angle α22 is adjusted by the change in the difference between the real-time measured echo photon number N0 and the reference value L, until the difference between the real-time measured echo photon number N0 and the reference value L is less than the threshold value δ, at which point the adjustment is stopped, and the fine adjustment of the telescope is completed.

[0013] Compared with the prior art, the present invention has the following advantages: (1) The device of the present invention overcomes the influence of the spatiotemporal distribution limitation of conventional mid-to-upper atmosphere detection lidar observation. It can be used as a fixed station for observation or as a mobile station for observation, and can realize continuous observation in the region, thereby greatly improving the spatiotemporal distribution characteristics of mid-to-upper atmosphere observation data.

[0014] (2) The method of the present invention can adjust the receiving and sending matching in real time during transportation and movement, thereby overcoming the adverse effects caused by vibration during vehicle-mounted mobile observation. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the device of the present invention; Figure labels and corresponding component names: 1-Pulse laser generator; 2-Emitting optical path; 3-Reflector; 4-Telescope; 5-Echo signal processing module; 6-Rotable optical platform; 7-Data processing and control module; 8-Photodetector; 9-Vehicle platform; 10-Reflector attitude monitoring module; 11-Reflector attitude adjustment motor; 12-Telescope attitude monitoring module; 13-Telescope attitude adjustment motor; 14-Weather monitoring module; 15-Solar panel; 16-Battery power supply module; 17-Mains power supply module; 18-Vehicle-mounted cabin. Detailed Implementation

[0016] To facilitate understanding and implementation of the present invention by those skilled in the art, the present invention will be further described in detail below with reference to embodiments. The embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0017] Example 1: like Figure 1As shown, a vehicle-mounted mobile lidar for detecting upper atmospheric phenomena includes a vehicle-mounted container 18 and, inside the container 18, a laser pulse generator, a reflector 3, a telescope 4, a reflector attitude monitoring module 10, a reflector attitude adjustment motor 11, a telescope attitude monitoring module 12, a telescope attitude adjustment motor 13, a photodetector 8, and a rotatable optical platform 6. The vehicle-mounted container 18 has an automatic skylight; when normally powered on, the skylight opens, allowing the pulsed laser to be emitted into the sky, and the echo signal falls into the receiving field of view of the telescope 4. The laser pulse generator is used to output the emitted beam to the reflector 3. The laser pulse generator, reflector 3, and telescope 4 are all included. The reflector attitude monitoring module 10, reflector attitude adjustment motor 11, and telescope attitude monitoring module 12 are all fixedly mounted on the rotatable optical platform 6. The receiving plane of the telescope 4 is parallel to the surface of the rotatable optical platform 6. The emitted beam is reflected by the reflector 3 and then directed vertically towards the sky along the surface of the rotatable optical platform 6. The reflector attitude adjustment motor 11 and the reflector attitude monitoring module 10 are both connected to the reflector 3. The telescope attitude monitoring module 12 and the telescope attitude adjustment motor 13 are both connected to the telescope 4. The light output port of the telescope 4 is also equipped with an echo signal processing module 5, which is connected to the photodetector 8.

[0018] The reflector attitude monitoring module 10 is used to collect the attitude position information α1 of the reflector 3. The attitude position information α1 of the reflector 3 includes the first angle α11 and the second angle α12 of the reflector 3. The reflector attitude adjustment motor 11 is used to adjust the first angle α11 and the second angle α12 of the reflector 3. The first angle α11 is the angle between the mirror normal of the reflector 3 and the X-axis direction of the rotatable optical platform 6, and the second angle α12 is the angle between the mirror normal of the reflector 3 and the Y-axis direction of the rotatable optical platform 6. Among them, the X-axis direction and Y-axis direction of the rotatable optical platform 6 are two mutually perpendicular directions within the surface of the rotatable optical platform 6.

[0019] The telescope attitude monitoring module 12 is used to collect the attitude position information α2 of the telescope 4. The attitude position information α2 of the telescope 4 includes the third angle α21 and the fourth angle α22 of the telescope 4. The telescope attitude adjustment motor 13 is used to adjust the third angle α21 and the fourth angle α22 of the telescope 4. The third angle α21 is the angle between the field of view of the telescope 4 and the X-axis direction of the rotatable optical platform 6, and the fourth angle α22 is the angle between the field of view of the telescope 4 and the Y-axis direction of the rotatable optical platform 6.

[0020] It also includes a data processing and control module 7, which includes an FPGA module and a Beidou navigation module. The FPGA module is connected to a laser pulse generating device, a reflector attitude monitoring module 10, a telescope attitude adjustment motor 13, a telescope attitude monitoring module 12, a telescope attitude adjustment motor 13, a rotatable optical platform 6, and a photodetector 8. Data processing and control module 7 also includes a Beidou navigation module, which provides real-time vehicle location information.

[0021] As one possible implementation, the vehicle-mounted container 18 is installed on the vehicle-mounted platform 9, which is generally a heavy-duty truck. The rotatable optical platform 6 is fixed in the rotatable vehicle-mounted container 18 by four liftable outriggers. When two adjacent outriggers are raised to the same height at the same time, the rotatable optical platform 6 can tilt at a corresponding angle. The lifting of the outriggers is achieved by the outrigger drive device, which is connected to the FPGA module and receives and executes the lifting commands issued by the FPGA module.

[0022] The FPGA module performs coarse adjustment of the reflector 3 and the telescope 4 based on the attitude position information: the reflector attitude monitoring module 10 collects the real-time attitude position information of the reflector 3 and sends it to the FPGA module. The FPGA module calculates the deviation value of the first angle and the deviation value of the second angle based on the optimal attitude position information of the reflector 3, and corrects the reflector 3 to the optimal attitude position through the reflector attitude adjustment motor 11. The telescope attitude monitoring module 12 collects the real-time attitude position information of the telescope 4 and sends it to the FPGA module. The FPGA module calculates the deviation values ​​of the third angle and the fourth angle based on the optimal attitude position information of the telescope 4, and corrects the telescope 4 to the optimal attitude position through the telescope attitude adjustment motor 13. The optimal attitude positions of mirror 3 and telescope 4 are respectively the attitude positions of mirror 3 and telescope 4 when the number of echo photons reaches its maximum value in a stationary state.

[0023] As one possible implementation, both the reflector attitude monitoring module 10 and the telescope attitude monitoring module 12 employ high-precision two-dimensional inclinometers. Typically, the resolution of a two-dimensional inclinometer can reach 0.001°, enabling real-time measurement of the tilt angle of an object in two mutually perpendicular directions and outputting the deviation angles in these two dimensions. This ensures real-time monitoring of the positional changes of the reflector 3 and the telescope 4, thereby monitoring changes in the direction of the emitted beam and the field of view of the telescope 4. The bumps and vibrations generated during vehicle operation will cause the direction of the emitted beam and the direction of the received field of view to deviate from the set direction. The two-dimensional inclinometer is used to collect the deviation angle and output it to the FPGA module. The FPGA module corrects the direction of the emitted beam and the direction of the received field of view by adjusting the motors (reflector attitude adjustment motor 11 and telescope attitude adjustment motor 13) based on the collected deviation value. The adjustment motor typically uses a high-precision stepper motor, such as the Leadshine 57CM26 or the Sanmei SS1702A04A, which can achieve a step angle of 1.8° and can be further subdivided into 512 steps, thereby achieving high-precision position offset; the FPGA module uses a high-speed FPGA with a data processing speed of more than 100MHz to ensure high-speed reading of echo data.

[0024] The echo signal processing module 5 is used to filter out background noise from the original echo, which is then converted into an electrical signal by the photodetector 8 and sent to the FPGA module for acquisition. The FPGA module fine-tunes the first angle α11 and the second angle α12 of the reflector 3 and the third angle α21 and the fourth angle α22 of the telescope 4 according to the reference value L, the threshold value δ, and the real-time measured echo photon number N0. When |L-N0|≤δ, the fine-tuning is completed.

[0025] The laser pulse generating device includes a pulsed laser generator 1 and an emitting optical path 2. The pulsed laser generator 1 is connected to an FPGA module, and the FPGA module controls the opening and closing of the pulsed laser generator 1. The horizontal laser generated by the pulsed laser generator 1 passes through the emitting optical path 2 to form an emitted laser and is output to the reflector 3.

[0026] The initial position of the optical platform is horizontal. When it is necessary to test parameters in other directions, such as east, south, west, and north, the angle between the rotatable optical platform 6 and the horizontal plane can be adjusted through the FPGA module so that the rotatable optical platform 6 forms an angle with the horizontal plane in each direction (such as east, south, west, and north), generally 60°.

[0027] It also includes a weather monitoring module 14, a solar panel 15, a battery power supply module 16, and a mains power supply module 17. The FPGA module is also connected to the weather monitoring module 14, the solar panel 15, the battery power supply module 16, and the mains power supply module 17. The FPGA module obtains the current weather status (including visibility and cloud thickness, etc.) from the weather monitoring module 14 in real time. When the system power supply is insufficient, the FPGA module will issue a warning to remind the battery to be charged. When mobile observation is not required, the system can also switch to mains power supply to charge the battery and use mains power for observation.

[0028] The vehicle-mounted container 18 can be a closed container with an automatically opening and closing sunroof installed on the top. A high-power battery is installed inside the vehicle-mounted container 18 to power the entire system. Solar panels 15 are installed on the sun-facing side of the vehicle-mounted container 18 and powered by a battery power supply module 16. A mains power supply interface is also retained. The vehicle-mounted container 18 is installed on the vehicle's on-board platform 9.

[0029] Example 2: A calibration method for a vehicle-mounted mobile lidar for detecting the upper atmosphere, utilizing the vehicle-mounted mobile lidar for detecting the upper atmosphere described in Example 1, includes the following steps: Step 1: The FPGA obtains the current weather status from the weather monitoring module 14. If the weather is in the set suitable weather condition for measurement, the pulse laser generator 1 is turned on to generate a laser. After passing through the emission adjustment optical path, the laser reaches the center of the reflector 3. The reflector 3 and the rotatable optical platform 6 form a 45° angle. The emitted laser then passes through the reflector 3 and is directed vertically towards the sky along the surface of the rotatable optical platform 6. The echo signal falls into the receiving field of view of the telescope 4. The echo signal processing module 5 performs filtering processing on the original echo light signal to filter out background interference. Then, it is converted into an electrical signal by the photoelectric converter and transmitted to the FPGA module, thus completing the detection of the echo signal. Step 2: Collect and record the optimal attitude position information of the reflector 3 and the telescope 4 when the echo photon number reaches its maximum value while the vehicle is stationary; and obtain historical observation data of the echo photon number at different altitudes under the current weather conditions as a reference value L, and set a threshold value δ. The attitude and position information of the reflector 3 includes the angle between the normal of the reflector 3 and the X-axis and Y-axis directions of the rotatable optical platform 6, and the attitude and position information of the telescope 4 includes the angle between the field of view of the telescope 4 and the X-axis and Y-axis directions of the rotatable optical platform 6. Step 3: During the vehicle's operation, the attitude monitoring module and the telescope attitude monitoring module 12 monitor the real-time attitude position information of the reflector 3 and the telescope 4, respectively, and send the information to the FPGA module. Step 4: Perform coarse adjustment of reflector 3 and telescope 4: The FPGA calculates the deviation value of the angle of reflector 3 based on the real-time attitude position information and the optimal attitude position information of reflector 3, and corrects the attitude position of reflector 3 according to the deviation value through reflector attitude adjustment motor 11. The FPGA calculates the angle deviation of the telescope 4 based on the real-time attitude position information and the optimal attitude position information of the telescope 4, and corrects the attitude of the telescope 4 according to the deviation value through the telescope attitude adjustment motor 13. Step 5: Fine-tune mirror 3: Adjust mirror 3 using real-time measured echo photon count until the difference between the real-time measured echo photon count N0 and the reference value L is less than the threshold value δ. Stop adjusting and record the current measured echo photon count as the final measured value of the echo photon count. Specifically: First, keep the attitude and position of telescope 4 and the second angle α12 unchanged. Adjust the first angle α11 by the change of the difference between the real-time measured echo photon number N0 and the reference value L until the real-time measured echo photon number N0 no longer changes. The adjustment of the first angle α11 is completed, and the adjustment of the second angle α12 is performed. Then, keeping the attitude and position of telescope 4 and the first angle α11 unchanged, the second angle α12 is adjusted by the change of the difference between the real-time measured echo photon number N0 and the reference value L, until the difference between the real-time measured echo photon number N0 and the reference value L is less than the threshold value δ, then the adjustment is stopped, and the fine adjustment of mirror 3 is completed. If adjusting mirror 3 fails to make the difference between the real-time measured echo photon count N0 and the reference value L less than the threshold value δ, then mirror 3 is held at the position where N0 is at its maximum. Telescope 4 is then fine-tuned until the difference between the real-time measured echo photon count N0 and the reference value L is less than the threshold value δ. At this point, adjustment is stopped, and the current measured echo photon count is recorded as the final measured value of the echo photon count. Specifically: First, keep the attitude and position of the reflector 3 and the fourth angle α22 unchanged. Adjust the third angle α21 by the change of the difference between the real-time measured echo photon number N0 and the reference value L until the real-time measured echo photon number N0 no longer changes. The adjustment of the third angle α21 is completed, and the adjustment of the fourth angle α22 is performed. Then, keeping the attitude and position of the reflector 3 and the third angle α21 unchanged, the fourth angle α22 is adjusted by the change in the difference between the real-time measured echo photon number N0 and the reference value L, until the difference between the real-time measured echo photon number N0 and the reference value L is less than the threshold value δ, at which point the adjustment is stopped, and the fine adjustment of the telescope 4 is completed.

[0030] Step 6: The FPGA module performs real-time inversion of the final measured value of the echo photon number, obtains atmospheric wind field, temperature and density data at the current location, and obtains real-time location information from the Beidou navigation module to plot continuous vertical atmospheric wind field, temperature and density distribution curves.

[0031] The generated distribution curve data can be stored on the storage medium of the vehicle-mounted container 18 and retrieved periodically, or the data can be uploaded via a wireless communication module.

[0032] Step 7: The initial position of the optical platform is horizontal. When it is necessary to measure parameters in other directions (such as east, south, west, and north), the angle between the rotatable optical platform 6 and the horizontal plane is adjusted through the FPGA module. Then, steps 1 to 6 are repeated to draw continuous atmospheric wind field, temperature, and density distribution curves in other directions.

[0033] It should be noted that the embodiments described in this invention are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains can make various modifications or additions to the described embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. A mobile vehicle-mounted lidar for detecting the middle and upper atmosphere, comprising a laser pulse generator, a mirror (3) and a telescope (4), characterized in that The application also comprises a vehicle-mounted shelter (18), a mirror attitude monitoring module (10), a mirror attitude adjusting motor (11), a telescope attitude monitoring module (12), a telescope attitude adjusting motor (13), a photoelectric detector (8) and a rotatable optical platform (6), the vehicle-mounted shelter (18) is provided with a skylight, and the rotatable optical platform (6) is fixedly arranged in the vehicle-mounted shelter (18); the laser pulse generating device outputs emitted laser onto the mirror (3), and the laser pulse generating device, the mirror (3), the telescope (4), the mirror attitude monitoring module (10), the mirror attitude adjusting motor (11), the telescope attitude monitoring module (12) and the telescope attitude adjusting motor (13) are all arranged on the rotatable optical platform (6), the receiving plane of the telescope (4) is parallel to the surface of the rotatable optical platform (6), the emitted laser is reflected by the mirror (3) and then vertically irradiates the sky along the surface of the rotatable optical platform (6), the mirror attitude adjusting motor (11) and the mirror attitude monitoring module (10) are connected with the mirror (3), the telescope attitude monitoring module (12) and the telescope attitude adjusting motor (13) are connected with the telescope (4), and the light outlet of the telescope (4) is further provided with a echo signal processing module (5), and the echo signal processing module (5) is connected with the photoelectric detector (8).

2. The mobile vehicle-mounted middle and upper atmosphere sounding laser radar of claim 1, wherein, The mirror attitude monitoring module (10) is used for collecting the attitude position information α1 of the mirror (3), the attitude position information α1 of the mirror (3) comprises a first angle α11 and a second angle α12 of the mirror (3), the mirror attitude adjusting motor (11) is used for adjusting the first angle α11 and the second angle α12 of the mirror (3), wherein the first angle α11 is the included angle between the mirror normal of the mirror (3) and the X-axis direction of the rotatable optical platform (6), and the second angle α12 is the included angle between the mirror normal of the mirror (3) and the Y-axis direction of the rotatable optical platform (6); The telescope attitude monitoring module (12) is used for collecting the attitude position information α2 of the telescope (4), the attitude position information α2 of the telescope (4) comprises a third angle α21 and a fourth angle α22 of the telescope (4), and the telescope attitude adjusting motor (13) is used for adjusting the third angle α21 and the fourth angle α22 of the telescope (4), wherein the third angle α21 is the included angle between the field of view direction of the telescope (4) and the X-axis direction of the rotatable optical platform (6), and the fourth angle α22 is the included angle between the field of view direction of the telescope (4) and the Y-axis direction of the rotatable optical platform (6).

3. The mobile vehicle-borne middle and upper atmosphere sounding lidar according to claim 2, characterized in that, The application also comprises a data processing and control module (7), the data processing and control module (7) comprises an FPGA module and a Beidou navigation module, and the FPGA module is connected with the laser pulse generating device, the mirror attitude monitoring module (10), the mirror attitude adjusting motor (11), the telescope attitude monitoring module (12), the telescope attitude adjusting motor (13), the rotatable optical platform (6) and the photoelectric detector (8). The data processing and control module (7) further comprises a Beidou navigation module, which provides real-time vehicle position information.

4. The mobile vehicle-mounted middle and upper atmosphere sounding lidar according to claim 3, characterized in that, The FPGA module coarsely adjusts the mirror (3) and the telescope (4) according to the attitude position information: the real-time attitude position information of the mirror (3) collected by the mirror attitude monitoring module (10) is sent to the FPGA module, the FPGA module calculates the deviation values of the first angle and the second angle according to the optimal attitude position information of the mirror (3), and corrects the mirror (3) to the optimal attitude position through the mirror attitude adjusting motor (11); The real-time attitude position information of the telescope (4) collected by the telescope attitude monitoring module (12) is sent to the FPGA module, the FPGA module calculates the deviation values of the third angle and the fourth angle according to the optimal attitude position information of the telescope (4), and corrects the telescope (4) to the optimal attitude position through the telescope attitude adjusting motor (13); The optimal attitude position information of the mirror (3) and the telescope (4) is the attitude position information of the mirror (3) and the telescope (4) when the number of echo photons reaches the maximum in the static state.

5. The mobile vehicle-borne middle and upper atmosphere sounding lidar according to claim 4, characterized in that, The echo signal processing module (5) is used for filtering background noise of the original echo, and then converting the echo into an electrical signal through a photoelectric detector (8) and sending the electrical signal to the FPGA module for collection. The FPGA module finely adjusts the first angle α11 and the second angle α12 of the mirror (3) and the third angle α21 and the fourth angle α22 of the telescope (4) according to the reference value L, the threshold value δ and the real-time measured echo photon number N0 of the echo photon number. When |L-N0|≤δ, the fine adjustment is completed.

6. The mobile vehicle-borne middle and upper atmosphere sounding lidar according to claim 5, characterized in that, The laser pulse generating device comprises a pulse laser generator (1) and a transmission light path (2). The pulse laser generator (1) is connected with the FPGA module, and the FPGA module controls the opening and closing of the pulse laser generator (1). The transmission laser generated by the pulse laser generator (1) is transmitted to the mirror (3) after being adjusted by the transmission light path (2).

7. The mobile vehicle-borne middle and upper atmosphere sounding lidar according to claim 6, characterized in that, It also comprises a weather monitoring module (14), a solar panel (15), a battery power supply module (16) and a mains power supply module (17). The FPGA module is also connected with the weather monitoring module (14), the solar panel (15), the battery power supply module (16) and the mains power supply module (17).

8. A calibration method of a vehicle-mounted mobile sounding middle and high atmospheric sounding lidar, using the vehicle-mounted mobile sounding middle and high atmospheric sounding lidar of claim 7, characterized in that, The method comprises the following steps: Step 1: The FPGA module obtains the current weather state from the weather monitoring module (14). If it is in the set weather state suitable for measurement, the pulse laser generator (1) is started to generate horizontal laser. After being adjusted by the transmission light path, the horizontal laser reaches the center of the mirror (3), and is vertically shot to the sky along the surface of the rotatable platform. The echo signal falls into the receiving field of view of the telescope (4). The echo signal processing module (5) filters the interference of background light after filtering the echo signal, and then converts the echo signal into an electrical signal through a photoelectric converter and transmits the electrical signal to the FPGA module, thereby completing the detection of the echo signal; Step 2, by collecting and recording the optimal attitude position information of the mirror (3) and the optimal attitude position information of the telescope (4) when the echo photon number reaches the maximum value in the static state of the vehicle; and obtaining the historical observation data of the echo photon number at different heights under the current weather condition as the reference value L, and setting the threshold value δ; Step 3, during the driving process of the vehicle, the real-time attitude position information of the mirror (3) and the real-time attitude position information of the telescope (4) are monitored by the mirror attitude monitoring module (10) and the telescope attitude monitoring module (12) respectively, and are sent to the FPGA module; Step 4, coarse adjustment of the mirror (3) and the telescope (4): the FPGA module calculates the deviation value of the angle of the mirror (3) according to the real-time attitude position information of the mirror (3) and the optimal attitude position information of the mirror (3), and corrects the attitude of the mirror (3) according to the deviation value through the mirror attitude adjusting motor (11); The FPGA module calculates the deviation value of the angle of the telescope (4) according to the real-time attitude position information of the telescope (4) and the optimal attitude position information of the telescope (4), and corrects the attitude of the telescope (4) according to the deviation value through the telescope attitude adjusting motor (13); Step 5, fine adjustment of the mirror (3): the mirror (3) is adjusted by the real-time measured echo photon number, and when the difference between the real-time measured echo photon number N0 and the reference value L is less than the threshold value δ, the adjustment is stopped, and the measurement value of the current echo photon number is recorded as the final measurement value of the echo photon number; If the adjustment of the mirror (3) cannot make the difference between the real-time measured echo photon number N0 and the reference value L less than the threshold value δ, the mirror (3) is kept at the attitude position of the maximum N0, and then the telescope (4) is fine adjusted until the difference between the real-time measured echo photon number N0 and the reference value L is less than the threshold value δ, and the adjustment is stopped, and the measurement value of the current echo photon number is recorded as the final measurement value of the echo photon number; Step 6, the FPGA module inverses the final measurement value of the echo photon number in real time, obtains the atmospheric wind field, temperature and density data at the current position, and obtains the real-time position information from the Beidou navigation module, and draws the continuous atmospheric wind field, temperature and density distribution curve; Step 7, the initial position of the optical platform is horizontal position, when the parameters in other directions need to be measured, the angle between the rotatable optical platform (6) and the horizontal plane is adjusted by the FPGA module, and then steps 1-6 are repeated, so as to draw the continuous atmospheric wind field, temperature and density distribution curve in other directions.

9. The calibration method of a mobile vehicle-mounted middle and upper atmospheric detection lidar according to claim 8, characterized in that, The fine adjustment of the mirror (3) in step 5 specifically includes the following process: Firstly, keep the attitude position and the second angle α12 of the telescope (4) unchanged, adjust the first angle α11 by the change of the difference between the real-time measured echo photon number N0 and the reference value L, until the real-time measured echo photon number N0 no longer changes, the adjustment of the first angle α11 is completed, and the adjustment of the second angle α12 is performed; Then, the attitude position and the first angle α11 of the telescope (4) are kept unchanged, the second angle α12 is adjusted according to the change of the difference between the real-time measured echo photon number N0 and the reference value L, until the difference between the real-time measured echo photon number N0 and the reference value L is less than the threshold value δ, the adjustment is stopped, and the fine adjustment of the mirror (3) is completed. The fine adjustment of the mirror (3) in step 5 specifically includes the following process: First, the attitude position and the fourth angle α22 of the mirror (3) are kept unchanged, the third angle α21 is adjusted according to the change of the difference between the real-time measured echo photon number N0 and the reference value L, until the real-time measured echo photon number N0 no longer changes, the adjustment of the third angle α21 is completed, and the adjustment of the fourth angle α22 is performed; Then, the attitude position and the third angle α21 of the mirror (3) are kept unchanged, the fourth angle α22 is adjusted according to the change of the difference between the real-time measured echo photon number N0 and the reference value L, until the difference between the real-time measured echo photon number N0 and the reference value L is less than the threshold value δ, the adjustment is stopped, and the fine adjustment of the telescope (4) is completed.

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