Measurement method of an onboard three-dimensional scanning wind lidar

Abstract

The present application provides a measurement method for a shipborne three-dimensional scanning wind lidar, including: obtaining the attitude information of the ship through a combined inertial navigation, where the attitude information includes the heading angle, the pitch angle, and the roll angle; determining the azimuth angle and the pitch angle of the laser beam of the shipborne three-dimensional scanning wind lidar in the geographic coordinate system according to the attitude information and a preset coordinate transformation model between the radar coordinate system and the geographic coordinate system; controlling the shipborne three-dimensional scanning wind lidar to emit a laser beam and receive the reflected echo signal according to the azimuth angle and the pitch angle; and obtaining the three-dimensional velocity component information of the wind field according to the reflected echo signal to obtain a three-dimensional wind field.

Description

Technical Field

[0001] The present invention relates to the field of information technology, and in particular, to a measurement method for an on-board three-dimensional scanning wind lidar. Background Art

[0002] The on-board lidar wind measurement technology faces a key technical problem in the measurement of the offshore wind field: how to accurately measure and reconstruct the three-dimensional wind field under the condition of continuous movement of the ship. The offshore environment is complex and changeable, and the ship is constantly swaying in the waves, resulting in continuous changes in the coordinate system of the lidar wind measurement equipment, which seriously affects the measurement accuracy of the wind speed and direction. The traditional static wind measurement method is difficult to adapt to this dynamic environment and cannot accurately capture the true state of the offshore wind field. In addition, the movement of the ship itself will introduce additional Doppler effects, interfering with the calculation of the wind speed. These factors combined make the measurement of the offshore wind field face great challenges. How to achieve accurate conversion between the lidar wind measurement system and the geographic coordinate system under the condition of ship movement, eliminate the errors caused by ship movement, and accurately reconstruct the three-dimensional wind field has become the core problem to be solved urgently. The solution to this problem is of great significance for applications such as the site selection of offshore wind farms and marine meteorological monitoring, and is directly related to the accuracy of the assessment of offshore wind energy resources and the safety of marine engineering. Summary of the Invention

[0003] The present invention aims to provide a measurement method for an on-board three-dimensional scanning wind lidar with high precision, good reliability and high efficiency.

[0004] The technical solution adopted by the present invention is: a measurement method for an on-board three-dimensional scanning wind lidar, wherein the wind lidar is arranged on a ship, and the method includes the following steps:

[0005] S1. Obtain the attitude information of the ship through a combined inertial navigation system, and the attitude information includes the heading angle , the pitch angle and the roll angle ;

[0006] S2. Determine the azimuth angle and elevation angle of the laser beam of the wind lidar in the geographic coordinate system according to the attitude information and the preset coordinate transformation model between the radar coordinate system and the geographic coordinate system;

[0007] S3. Control the wind lidar to emit a laser beam and receive the reflected echo signal according to the determined azimuth angle and elevation angle;

[0008] S4. Obtain the three-dimensional velocity component information of the wind field according to the reflected echo signal to obtain a three-dimensional wind field;

[0009] S5. Establish a radial velocity correction model to correct the radial velocity obtained in step S4, and obtain in real time the true wind field radial velocity in the geographical coordinate system after deducting the influence of the ship's velocity.

[0010] Further, the specific steps of step S2 include:

[0011] S21. Determine the Euler angle transformation matrix according to the heading angle, pitch angle, and roll angle obtained in step S1:

[0012] Obtain the heading angle of the wind measurement lidar through inertial navigation , pitch angle and roll angle ,

[0013] The conversion relationship from the radar coordinate system and the geographical coordinate system to the radar coordinate system is:

[0014] (1)

[0015] Among them, the transformation matrix of the three Euler angles is:

[0016] (2)

[0017] Among them, Y, P, and R are respectively the heading angle , pitch angle and roll angle matrices of the ship, the direction is defined as the left-handed system, the heading angle is 0 when pointing north and positive in the clockwise direction, the pitch angle is positive when looking down, the roll angle is positive when tilting to the left, the angle unit is radians, and the wind direction vector R LOS The relationship with the radar angle is expressed as:

[0018] (3)

[0019] Among them and are respectively the northward angle and the pitch angle of the beam i in the radar coordinate system;

[0020] S22. Convert the laser beam emission angle of the wind measurement lidar in the radar coordinate system into the azimuth angle and pitch angle in the geographical coordinate system through the Euler angle transformation matrix:

[0021] The direction of emitting the laser beam in the geographical coordinate system is:

[0022] (4)

[0023] Obtain the new azimuth angle and pitch angle which are respectively

[0024] (5).

[0025] Further, the specific steps of the S4 step are as follows:

[0026] Obtain the radial wind speeds in different beam directions, and determine the velocity components of the wind field in the east, north, and vertical directions in the geographic coordinate system according to each radial wind speed component:

[0027] Through formula (4) and formula (5), obtain four new azimuth vectors. Assuming that all four beams are measured normally, obtain the new laser Doppler velocimetry radial wind speed:

[0028] (6)

[0029] Simplify formula (6), and let formula (6) be:

[0030] AX = b (7)

[0031] Then (8)

[0032] Wherein, (9)

[0033] (10)

[0034] (11)

[0035] is the transpose matrix of the matrix is the inverse matrix of the matrix , and b is the laser Doppler velocimetry radial wind speed of the four beams.

[0036] Further, the specific steps of the S5 are as follows:

[0037] Correct the radial wind speed according to the sailing speed of the ship to obtain the corrected radial wind speed components:

[0038] Obtain the longitude and latitude of the ship through GNSS and convert them to the Cartesian coordinate system:

[0039] (12),

[0040] Wherein is the longitude, is the latitude, is the elevation, taking the height difference between the deck and the sea surface, , , , returned are the coordinates in the Earth-Centered Earth-Fixed coordinate system. At this time, they are converted to the ship-centered northeast-up coordinate system (e, n, u):

[0041] (13),

[0042] For Taking the first-order partial derivative with respect to time, the ship's speed can be obtained as:

[0043] (14)

[0044] The radial velocity of the actual wind field is the superposition of the ship's motion velocity and the measured radial wind speed. The radial wind speed is positive when it is away from the radar:

[0045] (15)

[0046] The horizontal wind speed is

[0047] (16)

[0048] The wind direction is

[0049] (17),

[0050] Finally, the true radial velocity of the wind field in the geographic coordinate system after deducting the influence of the ship's speed is obtained in real time.

[0051] In addition, after the step S5, the following steps are further included:

[0052] By the least squares method, the velocity components of the wind field in the geographic coordinate system are fitted and solved from the corrected radial wind speed components;

[0053] According to the three-dimensional velocity component information of the wind field, combined with the wind field information measured by the radar at different heights, the three-dimensional wind field around the ship is reconstructed;

[0054] Combined with the navigation position information of the ship, a wind field distribution map is generated and the wind field distribution map is displayed.

[0055] The technical solution provided by the embodiment of the present invention may include the following beneficial effects:

[0056] The present invention discloses an on - ship laser anemometry method, which solves the problem that the measurement accuracy of the offshore wind farm is affected by ship motion. This method obtains ship attitude information, establishes a transformation model between the radar coordinate system and the geographic coordinate system, and converts the laser beam direction from the radar coordinate system to the geographic coordinate system. It uses Doppler frequency shift information and the least - squares method for wind speed inversion, and reconstructs the three - dimensional wind field through interpolation fitting. Aiming at ship motion interference, the present invention compensates the wind speed according to the attitude information and updates the three - dimensional wind field, so as to obtain stable measurement results. This method effectively improves the accuracy of offshore wind field measurement, provides reliable data support for applications such as the siting of offshore wind farms and marine meteorological monitoring, and has important practical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 It is a top view of the anemometry lidar, the ship and the geographic coordinate system;

[0058] Figure 2 It is a simple flowchart of the method of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0059] To further understand the content of the present invention, the present invention will be described in detail in combination with the drawings and embodiments. The following further describes the present application in detail with reference to the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the related invention, rather than limiting the invention. In addition, it should be noted that for the sake of description, only parts related to the invention are shown in the drawings.

[0060] As Figure 1-2 shown, the measurement method of an on - ship three - dimensional scanning anemometry lidar in this embodiment may specifically include:

[0061] Step S1, obtain the attitude information of the ship, and the attitude information includes the heading angle , the pitch angle and the roll angle .

[0062] Adopt a combined inertial navigation system to collect ship motion data in real time. According to the collected ship motion data, extract the heading angle , the pitch angle and the roll angle . The heading angle , the pitch angle and the roll angle Perform data preprocessing on the information to eliminate noise and outliers. Based on the preprocessed attitude information, establish the initial mapping relationship between the radar coordinate system and the geographic coordinate system. If the ship's attitude changes, dynamically update the coordinate transformation model between the radar coordinate system and the geographic coordinate system. Use the coordinate transformation model to convert the laser pointing data in the radar coordinate system to the geographic coordinate system. Calculate the laser pointing stability parameter in the geographic coordinate system based on the converted laser pointing data. If the laser pointing stability parameter exceeds the set threshold, adjust the attitude compensation parameter of the radar coordinate system. Re-establish the coordinate transformation model between the radar coordinate system and the geographic coordinate system according to the adjusted attitude compensation parameter.

[0063] Specifically, the integrated inertial navigation system collects ship motion data in real time at a frequency of 100 Hz, including the raw measurement values of the accelerometer and gyroscope. Process the collected data through the Kalman filter algorithm to extract the heading angle , pitch angle and roll angle information, with the calculation accuracy controlled within 0.1 degrees. Perform data preprocessing on the extracted attitude information, use median filtering to eliminate noise, and remove outliers through threshold judgment to ensure data reliability. Based on the preprocessed attitude information, use the quaternion method to establish the initial mapping relationship between the radar coordinate system and the geographic coordinate system and determine the rotation matrix. If the ship's attitude changes, for example, the pitch angle exceeds 5 degrees, then dynamically update the coordinate transformation model and optimize the rotation matrix parameters using the least squares method. Convert the laser pointing data in the radar coordinate system to the geographic coordinate system through the coordinate transformation model, and calculate the laser pointing angle in the geographic coordinate system using matrix multiplication. Calculate the pointing stability parameter based on the converted laser pointing data, such as the standard deviation of angle fluctuation. If the standard deviation exceeds 0.5 degrees, adjust the attitude compensation parameter of the radar coordinate system and optimize the compensation amount using the PID control algorithm. Re-establish the coordinate transformation model between the radar coordinate system and the geographic coordinate system according to the adjusted attitude compensation parameter to ensure the stability of the laser pointing in the geographic coordinate system.

[0064] Step S2, determine the azimuth angle and elevation angle of the laser beam of the wind measurement lidar in the geographic coordinate system according to the attitude information and the preset coordinate transformation model between the radar coordinate system and the geographic coordinate system.

[0065] First, establish the coordinate transformation model between the radar coordinate system and the geographic coordinate system, and the coordinate transformation model includes a heading angle matrix, a pitch angle matrix, and a roll angle matrix.

[0066] The heading angle, roll angle, and pitch angle data of the ship are obtained in real time through a combined inertial navigation system. According to the heading angle data of the ship, a heading angle matrix is constructed. According to the pitch angle data of the ship, a pitch angle matrix is constructed. According to the roll angle data of the ship, a roll angle matrix is constructed. The heading angle matrix, pitch angle matrix, and roll angle matrix are subjected to matrix multiplication operations to obtain a coordinate transformation model from the radar coordinate system to the geographic coordinate system. The coordinate transformation model is used to transform the laser pointing data in the radar coordinate system to obtain the laser pointing data in the geographic coordinate system. If there is a deviation between the laser pointing data and the preset target direction in the geographic coordinate system, the feedback parameters of the laser pointing are adjusted. The coordinate transformation model is corrected in real time according to the feedback parameters, and the heading angle matrix, pitch angle matrix, and roll angle matrix are updated. Through the corrected coordinate transformation model, the wind measurement lidar is kept stable in the geographic coordinate system. The calculation process is as follows:

[0067] Step S21. Determine the Euler angle transformation matrix according to the heading angle, roll angle, and pitch angle obtained in step S1:

[0068] Obtain the heading angle of the wind measurement lidar through inertial navigation , pitch angle and roll angle ,

[0069] The conversion relationship from the radar coordinate system and the geographic coordinate system to the radar coordinate system is:

[0070] (1)

[0071] Among them, the conversion matrix of the three Euler angles is:

[0072] (2)

[0073] Among them, Y, P, and R are the heading angle , pitch angle and roll angle matrices of the ship, the direction is defined as the left-handed system, the heading angle is 0 when pointing north and positive in the clockwise direction, the pitch angle is positive when looking down, the roll angle is positive when tilting to the left, the angle unit is radians, and the wind vector R LOS The relationship with the radar angle is expressed as:

[0074] (3)

[0075] Among them and are the northward angle and pitch angle of the beam i in the radar coordinate system respectively.

[0076] Step S22: Convert the laser beam emission angle of the wind lidar in the radar coordinate system into the azimuth angle and elevation angle in the geographic coordinate system through the Euler angle transformation matrix. Obtain the northward angle and elevation angle of the laser beam in the radar coordinate system, and convert the northward angle and elevation angle of the laser beam to the geographic coordinate system according to the coordinate transformation model.

[0077] Obtain the northward angle and elevation angle of the laser beam in the radar coordinate system, and extract the azimuth information of the radar beam. According to the definition of the radar coordinate system, establish the conversion relationship model between the radar coordinate system and the geographic coordinate system. Use the coordinate transformation model to read the northward angle and elevation angle data in the radar coordinate system. If the conversion parameters between the radar coordinate system and the geographic coordinate system are complete, calculate the angle components in the geographic coordinate system according to the conversion parameters. Substitute the northward angle and elevation angle in the radar coordinate system into the coordinate transformation model to obtain the preliminary angle values in the geographic coordinate system. According to the definition of the geographic coordinate system, adjust the preliminary angle values to conform to the range and direction of the geographic coordinate system. If the angle values exceed the range of the geographic coordinate system, perform normalization processing on the angle values. Determine the final northward angle and elevation angle in the geographic coordinate system to complete the coordinate transformation. Output the northward angle and elevation angle data in the geographic coordinate system to provide input for subsequent wind field inversion. The calculation process is as follows:

[0078] The direction of emitting the laser beam in the geographic coordinate system is:

[0079] (4)

[0080] Obtain the new azimuth angle and elevation angle respectively as

[0081] (5).

[0082] Step S3: According to the determined azimuth angle and elevation angle, control the wind lidar to emit a laser beam and receive the reflected echo signal.

[0083] According to the converted northward angle and elevation angle, determine the direction of emitting the laser beam in the geographic coordinate system.

[0084] Obtain the laser beam direction data in the radar measurement coordinate system, and extract the azimuth and elevation angle information of the beam. According to the conversion relationship between the radar measurement coordinate and the geographic coordinate system, obtain the Euler angle matrices Y, P, and R, which correspond to the heading angle, pitch angle, and roll angle respectively. Use the Euler angle matrix Y to convert the azimuth angle in the radar measurement coordinate system to the northward angle in the geographic coordinate system. Use the Euler angle matrix P to convert the elevation angle in the radar measurement coordinate system to the elevation angle in the geographic coordinate system. According to the definition of the left-handed coordinate system, judge whether the heading angle points north as 0 and is positive clockwise, and adjust the calculation result of the northward angle. According to the definition of the left-handed coordinate system, judge whether the pitch angle is positive when looking down, and adjust the calculation result of the elevation angle. According to the definition of the left-handed coordinate system, judge whether the roll angle is positive when tilting to the left, and combine the roll angle matrix R to correct the final values of the northward angle and the elevation angle. Convert the corrected northward angle and elevation angle to the direction vector in the geographic coordinate system. Determine the emission direction of the laser beam in the geographic coordinate system to obtain the direction vector of the laser beam. Finally, control the wind-measuring lidar to emit a laser beam and receive the reflected echo signal.

[0085] In step S4, according to the reflected echo signal, obtain the three-dimensional velocity component information of the wind field to obtain the three-dimensional wind field.

[0086] First, according to the Doppler frequency shift information of the laser beam, use the least squares method for wind speed inversion to obtain the wind speed information. Obtain the Doppler frequency shift information of the laser beam and extract the frequency shift data. According to the frequency shift data, calculate the phase change amount of the laser beam. Use the least squares method to fit the linear relationship between the frequency shift data and the wind speed. According to the fitting result, establish a wind speed inversion model. Through the wind speed inversion model, calculate the initial wind speed value. If the wind speed value has abnormal fluctuations, use the Kalman filter algorithm to smooth the initial wind speed value. According to the smoothed wind speed value, update the parameters of the wind speed inversion model. Through the updated wind speed inversion model, recalculate the wind speed value. Obtain the final wind speed information, store it and output the result.

[0087] Secondly, interpolate and fit the wind speed information at different positions to reconstruct a three-dimensional wind field. Obtain the wind speed information at different positions, including the magnitude, direction, and position coordinates of the wind speed. Establish a three-dimensional spatial grid model based on the position coordinates to determine the spatial distribution of each grid point. Use the Lagrangian interpolation method to perform spatial interpolation on the wind speed information and calculate the estimated wind speed values at the grid points. If the wind speed information includes wind direction data, decompose the wind direction vectorially to obtain the horizontal and vertical components of the wind speed. Fit the wind speed components by the least squares method to optimize the accuracy of the interpolation results. Generate a three-dimensional wind speed field according to the fitting results to obtain the wind speed vectors at each grid point. Process the three-dimensional wind speed field using a smoothing algorithm to eliminate outliers in the interpolation and fitting processes. Combine with the atmospheric dynamics model to dynamically correct the three-dimensional wind speed field and improve the physical consistency of the wind field reconstruction. Output the reconstructed three-dimensional wind field data, including the magnitude, direction, and spatial distribution information of the wind speed.

[0088] The specific calculation steps of the above steps are as follows:

[0089] Obtain the radial wind speeds in different beam directions. According to each radial wind speed component, determine the velocity components of the wind field in the eastward, northward, and vertical directions in the geographical coordinate system:

[0090] Through formulas (4) and (5), obtain four new azimuth vectors. Assuming that all four beams are measured normally, obtain the new laser Doppler velocimetry radial wind speeds:

[0091] (6)

[0092] Simplify formula (6) and let formula (6) be:

[0093] AX = b (7)

[0094] Then (8)

[0095] Among them, (9)

[0096] (10)

[0097] (11),

[0098] is the transpose matrix of the matrix and is the inverse matrix of the matrix , and b is the laser Doppler velocimetry radial wind speeds of the four beams.

[0099] Step S5: If the laser beam is disturbed by the ship's movement, perform motion compensation on the wind speed information according to the attitude information to obtain the compensated wind speed information. Specifically, establish a radial velocity correction model to correct the radial velocity obtained in Step S4, and obtain the true radial velocity of the wind field in the geographic coordinate system after deducting the influence of the ship's speed in real time.

[0100] Obtain the attitude information of the ship, where the attitude information includes the angles of the heading angle, pitch angle, and roll angle. Obtain the wind speed measurement data of the laser beam and extract the original information of the wind speed. Calculate the offset of the laser beam according to the roll and pitch angles in the attitude information. Use the coordinate transformation method to convert the offset of the laser beam into a compensation value in the wind speed measurement coordinate system. Adjust the spatial position of the wind speed measurement data according to the compensation value. Determine whether the yaw angle in the attitude information exceeds a preset threshold. If it exceeds, recalculate the direction vector of the laser beam. Use the direction vector correction method to perform direction compensation on the wind speed measurement data. Combine the spatial position and direction compensation results to generate the motion-compensated wind speed information. Store the compensated wind speed information and update the wind speed measurement database. The specific calculation process of this step is as follows:

[0101] Correct the radial wind speed according to the ship's navigation speed to obtain the corrected radial wind speed components:

[0102] Obtain the longitude and latitude of the ship through GNSS and convert them to the Cartesian coordinate system:

[0103] (12),

[0104] where is the longitude, is the latitude, is the elevation, taking the height difference between the deck and the sea surface, , , , the returned is the coordinate in the Earth-centered Earth-fixed coordinate system. At this time, convert it to the ship-centered northeast-up coordinate system (e, n, u):

[0105] (13),

[0106] Take the first-order partial derivative of with respect to time, and the ship's speed can be obtained as:

[0107] (14)

[0108] The radial velocity of the actual wind field is the superposition of the ship's motion velocity and the measured radial wind speed. The radial wind speed is positive when it is away from the radar:

[0109] (15)

[0110] The horizontal wind speed is

[0111] (16)

[0112] The wind direction is

[0113] (17),

[0114] Finally, the true radial velocity of the wind field in the geographic coordinate system after deducting the influence of the ship's speed is obtained in real time.

[0115] Step S6, according to the compensated wind speed information, update the three-dimensional wind field to obtain a stable measurement result. Specifically:

[0116] By the least squares method, the velocity components of the wind field in the geographic coordinate system are fitted and solved from the corrected radial wind speed components;

[0117] According to the three-dimensional velocity component information of the wind field, combined with the wind field information measured by the radar at different heights, reconstruct the three-dimensional wind field in the area around the ship;

[0118] Combined with the navigation position information of the ship, generate a wind field distribution map and display the wind field distribution map.

[0119] Obtain the ship attitude information provided by the integrated inertial navigation, including the heading angle, roll angle, and pitch angle. According to the ship attitude information, establish a coordinate transformation model between the radar coordinate system and the geographic coordinate system. Through the coordinate transformation model, convert the wind speed data measured by the radar from the radar coordinate system to the geographic coordinate system. Obtain the wind speed data in the geographic coordinate system and judge whether there is an error caused by the ship's movement. If there is an error caused by the ship's movement, use an error compensation algorithm to compensate the wind speed data. According to the compensated wind speed information, calculate the three-dimensional wind speed components, including the wind speed in the horizontal and vertical directions. Use the time series analysis method to smooth the three-dimensional wind speed components to eliminate short-term fluctuations. According to the smoothed three-dimensional wind speed components, update the three-dimensional wind field model to obtain a stable wind field distribution. Store the updated three-dimensional wind field data in the database for subsequent analysis and application.

[0120] The above description is only the preferred embodiment of the present application and the description of the applied technical principles. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by the specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the concept of the present application. For example, the technical solutions formed by mutually replacing the above features with the (but not limited to) technical features with similar functions disclosed in the present application.

Claims

1. A measurement method for a shipborne three-dimensional scanning wind laser radar, wherein: The wind laser radar is arranged on a ship, and is characterized in that the method comprises the following steps: S1. Obtaining the ship's attitude information through combined inertial navigation, the attitude information includes the heading angle , pitch angle and roll angle ; S2. Determine the azimuth and elevation angle of the laser beam of the wind laser radar in the geographic coordinate system according to the attitude information and the coordinate transformation model between the preset radar coordinate system and the geographic coordinate system; S3. According to the determined azimuth and elevation angles, control the wind laser radar to emit a laser beam and receive a reflected echo signal; S4. Obtain three-dimensional velocity component information of the wind field according to the reflected echo signal to obtain a three-dimensional wind field; S5. Establish a radial velocity correction model, correct the radial velocity obtained in step S4, and obtain the real wind field radial velocity in the geographic coordinate system minus the influence of the ship speed in real time; The specific steps of step S2 include: S21. According to the heading angle, pitch angle and roll angle obtained in step S1, determine the Euler angle conversion matrix: Obtaining the heading angle of wind laser radar through inertial navigation , pitch angle and roll angle , The conversion relationship from the radar coordinate system to the geographic coordinate system and to the radar coordinate system is: （1） The transformation matrix of the three Euler angles is: （2） Where Y, P, and R are the heading angles of the ship, respectively. , pitch angle and roll angle The direction is defined as a left-handed system, the heading angle is 0 to the north and is positive clockwise, the pitch angle is positive when it is tilted downward, and the roll angle is positive when it is tilted to the left. The angle unit is radians, and the wind direction vector R LOS The relationship with the radar angle is expressed as: （3） in and Beam i North angle and elevation angle in the radar coordinate system; S22. The laser beam emission angle of the wind laser radar in the radar coordinate system is converted into the azimuth and elevation angle in the geographic coordinate system through the Euler angle conversion matrix: The direction of the emitted laser beam in the geographic coordinate system is: （4） Get the new azimuth and pitch angle They are （5）。 2. The measurement method of a shipborne three-dimensional scanning wind laser radar according to claim 1, characterized in that: The S4 step is specifically as follows: Get the radial wind speed in different beam directions, and determine the speed components of the wind field in the east, north and vertical directions in the geographic coordinate system based on each radial wind speed component: Through formula (4) and formula (5), four new azimuth vectors are obtained. Assuming that the four beams are measured normally, the new laser velocity radial wind speed is obtained: （6） Simplify formula (6) and make it as follows: AX = b （7） but (8) in, (9) （10） （11） For the matrix The transposed matrix of For the matrix The inverse matrix of is, and b is the radial wind speed of the four-beam laser velocimetry.

3. The measurement method of a shipborne three-dimensional scanning wind laser radar according to claim 2, characterized in that: The specific steps of step S5 are: The radial wind speed is corrected according to the navigation speed of the ship to obtain the corrected radial wind speed components: Obtain the latitude and longitude of the ship through GNSS and convert it to the Cartesian coordinate system: （12）， in is the longitude, is the latitude, is the elevation, which is the height difference between the deck and the sea surface. , , , returned is the coordinate in the Earth-centered Earth-fixed coordinate system, which is now converted to the ship-centered Northeast Celestial coordinate system (e, n, u): （13）， right Taking the first-order partial derivative of time, we can get the ship speed as: （14） The radial velocity of the actual wind field is the superposition of the ship's motion speed and the measured radial wind speed, with the radial wind speed being positive when it is away from the radar: （15） The horizontal wind speed is （16） Wind direction （17）， Finally, the real wind field radial velocity is obtained in real time in the geographic coordinate system after deducting the influence of the ship speed.

4. The measurement method of a shipborne three-dimensional scanning wind laser radar according to claim 3, characterized in that: After the step S5, the following steps are also included: Through the least square method, the velocity components of the wind field in the geographic coordinate system are fitted by each corrected radial wind speed component; The three-dimensional wind field around the ship is reconstructed based on the three-dimensional velocity component information of the wind field and the wind field information measured by the radar at different heights; In combination with the navigation position information of the ship, a wind field distribution map is generated and displayed.

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