Aerostat platform small laser wind lidar device and its motion compensation method

Abstract

The present disclosure provides a kind of aerostat platform light laser wind sounding radar device and its motion compensation method, wherein the device includes: laser light source, for generating the pulsed light beam of preset energy and preset frequency;Transmitting optical system, including step-shaped wedge mirror or holographic optical element, for emitting pulsed light beam according to forward cone scanning mode, and receiving echo signal;Laser detector, for detecting echo signal, obtaining the frequency shift of echo signal;Processor, for representing the relative velocity of the wind field to be measured based on the speed of aerostat platform;Based on the attitude of aerostat platform, the azimuth of pulsed light beam in geodetic coordinate system is calculated;The relative radial velocity is obtained by projecting the relative velocity of the wind field to be measured relative to the azimuth of pulsed light beam in geodetic coordinate system of aerostat platform;And according to the relative radial velocity and the frequency shift of echo signal, the wind field to be measured is inverted.

Description

Technical Field

[0001] This disclosure relates to the field of wind field observation technology, and in particular to a lightweight laser wind radar device for an airship platform and a motion compensation method. Background Technology

[0002] Wind fields are crucial observational indicators in multiple scientific fields, including meteorology and aerodynamics. Traditional wind measurement methods suffer from drawbacks such as narrow detection range and poor resolution. Laser wind radar, however, utilizes the Doppler shift of the backscattered signal from an emitted laser beam via aerosols or gas molecules to invert wind speed, and then uses wind speed information from multiple angles to invert wind direction. It offers advantages such as high measurement accuracy, long detection range, and high spatiotemporal resolution, demonstrating significant application potential in aviation safety, wind energy utilization, and meteorological observation.

[0003] To collect wind field information above, below, and directly in front of the platform, the lidar device needs to be designed with specific scanning modes and mechanical structures to constrain the beam path and achieve the predetermined scanning mode. Existing lidar wind measurement radars generally use two-axis steering mechanisms or wedge prisms. Two-axis steering mechanisms are bulky and heavy, while the thickness of wedge prisms increases linearly with the increase of the receiver aperture, failing to meet the requirements for portability. In addition, the platform carrying the lidar device undergoes translational and attitude changes, which in principle affects the accuracy of Doppler velocity measurement. To achieve high-precision wind field measurement, existing solutions generally use an airborne stabilized platform to mount the radar. This platform is bulky, heavy, and consumes a lot of power, failing to meet the lightweight application requirements of airship platforms. Summary of the Invention

[0004] In view of the above problems, the present invention provides a lightweight laser wind radar device and motion compensation method for an airship platform to solve the above technical problems.

[0005] The first aspect of this disclosure provides a lightweight laser wind radar device for an airship platform, comprising: a laser source for generating a pulse beam of preset energy and preset frequency; a transceiver optical system, including a stepped wedge mirror or a holographic optical element, disposed on the exit path of the pulse beam, for emitting the pulse beam in a forward conical scanning mode and receiving the echo signal of the pulse beam; a laser detector disposed on the incident path of the echo signal after it passes through the transceiver optical system, for detecting the echo signal and obtaining the frequency shift of the echo signal; a processor connected to the laser detector, for calculating the velocity of the airship platform based on the real-time position information of the airship platform, and obtaining an expression for the relative velocity of the wind field to be measured relative to the airship platform based on the velocity of the airship platform; calculating the azimuth of the pulse beam in a geodetic coordinate system based on the attitude of the airship platform; projecting the relative velocity onto the azimuth of the pulse beam in the geodetic coordinate system to obtain an expression for the relative radial velocity; and inverting the wind field to be measured based on the expression for the relative radial velocity and the frequency shift of the echo signal.

[0006] According to embodiments of this disclosure, it further includes: a controller for controlling the rotation of the stepped wedge mirror or holographic optical element to cause the pulse beam to deflect at an angle and converge.

[0007] According to embodiments of this disclosure, the stepped wedge mirror includes a central ordinary wedge mirror and a stepped wedge mirror. The central ordinary wedge mirror is inserted into a through hole in the center of the stepped wedge mirror, with its bottom surface coplanar with the bottom surface of the stepped wedge mirror, and its inclined surface extending out of the through hole. The upper surface of the stepped wedge mirror has multiple parallel steps of equal height, and one side of each step is aligned with the inclined surface of the central ordinary wedge mirror in both direction and angle. According to embodiments of this disclosure, the pulsed laser is emitted from the central ordinary wedge mirror.

[0008] The second aspect of this disclosure provides a motion compensation method for a lightweight laser wind radar device for an airship platform, applied to the device as described in any of the first aspects, comprising: calculating the velocity of the airship platform based on real-time position information of the airship platform, and obtaining an expression for the relative velocity of the wind field to be measured relative to the airship platform based on the velocity of the airship platform; calculating the azimuth of the pulse beam generated by the lightweight laser wind radar device for the airship platform in a geodetic coordinate system based on the attitude of the airship platform; projecting the relative velocity onto the azimuth of the pulse beam in the geodetic coordinate system to obtain an expression for the relative radial velocity; and inverting the wind field to be measured based on the expression for the relative radial velocity and the frequency shift of the echo signal of the pulse beam.

[0009] According to embodiments of this disclosure, the step of calculating the velocity of the airship platform based on its real-time location information and obtaining an expression for the relative velocity of the wind field to be measured relative to the airship platform based on the airship platform's velocity includes: obtaining the real-time location information of the airship platform based on a GNSS global positioning system; performing differential processing on the real-time location information to obtain the velocity of the airship platform; pre-setting the wind speed of the wind field to be measured, calculating the difference between the wind speed of the wind field to be measured and the velocity of the airship platform, and obtaining the expression for the relative velocity.

[0010] According to embodiments of this disclosure, calculating the azimuth of the pulse beam generated by the lightweight laser wind radar device on the airship platform in the geodetic coordinate system based on the attitude of the airship platform includes: obtaining the attitude angle of the airship platform through an IMU inertial navigation system; obtaining the azimuth of the pulse beam in the coordinate system of the airship platform; and converting the azimuth of the pulse beam to the geodetic coordinate system based on the attitude angle of the airship platform.

[0011] According to an embodiment of this disclosure, the step of inverting the wind field to be measured based on the expression of the relative radial velocity and the frequency shift of the echo signal of the pulse beam includes: representing the relative radial velocity using the frequency shift of the echo signal according to the Doppler principle; and solving the expression of the relative radial velocity based on the relative radial velocity represented by the frequency shift to obtain the wind speed of the wind field to be measured.

[0012] According to an embodiment of this disclosure, the method includes: calculating half the product of the echo time and the speed of light of the pulse beam, and multiplying it by the height of the pulse beam per unit length in the geodetic coordinate system to obtain a height compensation value; and calculating the sum of the height compensation value and the height of the airship platform in the geodetic coordinate system to obtain the height of the wind field to be measured.

[0013] The above-described at least one technical solution adopted in the embodiments of this disclosure can achieve the following beneficial effects:

[0014] This disclosure provides a lightweight and compact laser wind radar device for an airship platform. Compared with traditional methods that use mechanical shafts or rotating ordinary wedge prisms, this disclosure uses a stepped wedge prism with an ordinary wedge prism at the center and independent wedge prisms at the edges that are at the same angle to the center but are stepped and separate. This effectively reduces the overall thickness of the prism. The device can also use holographic optical elements to deflect light, all of which contribute to the miniaturization of the device.

[0015] This disclosure also provides a motion compensation method for a lightweight laser wind radar device on an airship platform. The platform carrying the device undergoes translational and attitude changes, which in principle affect the accuracy of Doppler velocity measurement. To achieve high-precision wind field measurement, existing solutions generally use an airborne stabilization platform to carry the radar. This platform is large in size and weight and consumes a lot of power, which cannot meet the lightweight application requirements of airship platforms. The motion compensation algorithm solves this problem and can reduce the weight of the airborne stabilization platform for the device. Attached Figure Description

[0016] To gain a more complete understanding of this disclosure and its advantages, reference will now be made to the following description taken in conjunction with the accompanying drawings, wherein:

[0017] Figure 1 This schematic diagram illustrates the structure of a lightweight laser wind-measuring radar device for an airship platform according to an embodiment of the present disclosure.

[0018] Figure 2 This schematic diagram illustrates the scanning mode of a lightweight laser wind-measuring radar device for an airship platform according to an embodiment of the present disclosure.

[0019] Figure 3 This schematic diagram illustrates a scanning mode implementation method of a lightweight laser wind-measuring radar device for an airship platform provided in an embodiment of this disclosure.

[0020] Figure 4A This schematic diagram illustrates a stepped wedge mirror provided in an embodiment of the present disclosure;

[0021] Figure 4B A schematic cross-sectional view of a stepped wedge mirror provided in an embodiment of this disclosure is shown.

[0022] Figure 5 The illustration shows a schematic flowchart of a motion compensation method for a lightweight laser wind-measuring radar device for an airship platform provided in an embodiment of this disclosure. Detailed Implementation

[0023] The embodiments of the present disclosure will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the disclosure. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of the present disclosure for ease of explanation. However, it will be apparent that one or more embodiments may be practiced without these specific details. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concepts of the present disclosure.

[0024] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0025] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0026] The accompanying drawings show some block diagrams and / or flowcharts. It should be understood that some blocks or combinations thereof in the block diagrams and / or flowcharts can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when executed by the processor, these instructions can create means for implementing the functions / operations described in these block diagrams and / or flowcharts.

[0027] Figure 1 The schematic diagram illustrates the structure of a lightweight laser wind-measuring radar device for an airship platform provided in an embodiment of this disclosure.

[0028] like Figure 1 As shown, this disclosure provides a lightweight laser wind radar device for an airship platform, including: a laser source 110, a transceiver optical system 120, a laser detector 130, and a processor 140.

[0029] The laser source 110 is used to generate a pulse beam with a preset energy and a preset frequency.

[0030] The transceiver optical system 120 includes a stepped wedge mirror or a holographic optical element, positioned in the emission path of the pulse beam, for transmitting the pulse beam in a forward conical scanning mode and receiving the echo signal of the pulse beam.

[0031] The laser detector 130 is positioned on the incident path of the echo signal after it passes through the transceiver optical system 120, and is used to detect the echo signal and obtain the frequency shift of the echo signal.

[0032] Processor 140 is connected to laser detector 130 and is used to perform motion compensation based on echo information and other sensor information, according to the basic principles of Doppler wind measurement, to obtain wind field vector information at different locations. The motion compensation performed by processor 140 may include: calculating the velocity of the airship platform based on its real-time position information, and obtaining an expression for the relative velocity of the wind field to be measured relative to the airship platform based on the airship platform's velocity; calculating the azimuth of the pulse beam in the geodetic coordinate system based on the airship platform's attitude; projecting the relative velocity onto the azimuth of the pulse beam in the geodetic coordinate system to obtain an expression for the relative radial velocity; and inverting the wind field to be measured based on the expression for the relative radial velocity and the frequency shift of the echo signal. This motion compensation method will be further explained later.

[0033] Figure 2 The illustration shows a schematic diagram of the scanning mode of a lightweight laser wind-measuring radar device for an airship platform provided in an embodiment of the present disclosure.

[0034] like Figure 2 Therefore, the lightweight laser wind-measuring radar device for an airship platform provided in this embodiment is mounted on an airship platform, which can be a hot air balloon, airship, etc. In this embodiment, the lightweight laser wind-measuring radar device for an airship platform also includes a controller for realizing the movement of the emitted light within the conical surface, thereby realizing the wind field vector measurement above, below, and directly in front of the platform.

[0035] When the aerostat performs an overhead wind field measurement, the control mechanism emits a beam of light from the upper semi-conical surface, such as... Figure 2 Under the assumption that only a horizontal wind field exists and that the wind field is uniform at the same height, directions 1 and 2 can be used to measure the wind field at different heights above. When the aerostat measures the wind field below, the control mechanism emits a beam of light from the lower half-cone surface, such as... Figure 2 Directions 5 and 6, under the assumption of a horizontal wind field that is uniform at the same height, can be used to measure the wind field at different heights below. When the aerostat is measuring the wind field directly in front, the control mechanism emits a beam of light on the horizontal plane, such as... Figure 2 Under the assumption that there is only a horizontal wind field and that the wind field is uniform at the same height, directions 3 and 4 can be used to measure the wind field directly in front of the platform at its height.

[0036] In this embodiment, the above scanning mode can be implemented through two structures to ensure the portability of the laser wind-measuring radar on this type of airship platform.

[0037] Figure 3 The illustration shows a schematic diagram of the scanning mode implementation of a lightweight laser wind-measuring radar device for an airship platform provided in an embodiment of this disclosure.

[0038] like Figure 3 As shown, the controller can adjust the deflection of the pulse beam by rotating the stepped wedge mirror. The controller can also adjust the deflection of the pulse beam by rotating the holographic optical element. When the holographic optical element or the stepped wedge mirror rotates around the central axis of the cone to be scanned, the emitted light can move on the surface of the cone.

[0039] Figure 4A and Figure 4B A schematic diagram and a cross-sectional view of a stepped wedge mirror provided in an embodiment of this disclosure are shown respectively.

[0040] like Figure 4A and Figure 4B As shown, the stepped wedge mirror includes a central ordinary wedge mirror 41 and a stepped wedge mirror 42. The central ordinary wedge mirror 41 is inserted into a through hole in the center of the stepped wedge mirror 42, with its bottom surface in the same plane as the bottom surface of the stepped wedge mirror 42, and its inclined surface extending out of the through hole. The upper surface of the stepped wedge mirror 42 has multiple parallel steps of the same height, and one side of each step is aligned with the inclined surface of the central ordinary wedge mirror 41 in both direction and angle. The stepped wedge mirrors 42, which are distributed around the perimeter, effectively reduce the overall thickness of the prism. The laser beam is emitted from the central independent wedge mirror 41, ensuring beam quality, while the reflected echo is incident from the entire stepped wedge mirror. The stepped prism as a whole deflects the beam, and when it rotates around the central axis of the cone to be scanned, the emitted light moves on the surface of the cone.

[0041] The lightweight laser wind radar device for airship platforms provided in this disclosure can achieve a scanning method that can measure the wind field above, below, and directly in front of the airship platform. Specifically, it employs a forward conical scanning method to provide effective observation of the wind field above, below, and directly in front of the platform. The device utilizes a scanning structure with holographic optical elements or stepped wedge mirrors, achieving a miniaturized design.

[0042] The platform carrying the device undergoes translational and attitude changes, which in principle affect the accuracy of Doppler velocity measurement. To achieve high-precision wind field measurement, existing solutions generally use aircraft-stabilized platforms to mount the radar. However, these platforms are large, heavy, and consume a lot of power, failing to meet the lightweight application requirements of airship platforms. This disclosure also provides a motion compensation method for a lightweight laser wind radar device for airship platforms, applicable to applications such as... Figure 1 The lightweight laser wind-measuring radar device for an airship platform shown in Figure 4 uses a motion compensation algorithm to solve this problem, which can reduce the weight of the aircraft stabilization platform.

[0043] The motion compensation method for a lightweight laser wind radar device for an airship platform provided in this embodiment includes steps S510 to S540.

[0044] S510 calculates the velocity of the airship platform based on its real-time position information, and obtains an expression for the relative velocity of the wind field under test relative to the airship platform based on the velocity of the airship platform.

[0045] S520 calculates the azimuth of the pulse beam generated by the lightweight laser wind radar device on the airship platform in the geodetic coordinate system.

[0046] S530, by projecting the relative velocity onto the orientation of the pulse beam in the geodetic coordinate system, we obtain the expression for the relative radial velocity.

[0047] S540, based on the expression for relative radial velocity and the frequency shift of the echo signal of the pulse beam, inverts the wind field to be measured.

[0048] Figure 5 The illustration shows a schematic flowchart of a motion compensation method for a lightweight laser wind-measuring radar device for an airship platform provided in an embodiment of this disclosure.

[0049] like Figure 5 As shown, the real-time attitude angle of the airship platform is obtained through the IMU inertial navigation system; the azimuth of the pulse beam in the coordinate system of the airship platform is acquired, and the azimuth of the pulse beam is transformed to the geodetic coordinate system based on the attitude angle of the airship platform. The real-time position information of the airship platform is obtained based on the GNSS global positioning system; the velocity of the airship platform is obtained by differentiating the real-time position information; the wind speed of the wind field to be measured is preset, and the difference between the wind speed of the wind field to be measured and the velocity of the airship platform is calculated to obtain the expression for the relative velocity. The relative velocity is projected onto the actual beam direction to represent the relative radial wind speed. The relative radial velocity is represented by the frequency shift of the echo signal according to the Doppler principle; the expression for the relative radial velocity is solved based on the frequency shift-represented relative radial velocity to obtain the wind speed of the wind field to be measured.

[0050] When performing wind field measurements, the motion compensation process is as follows:

[0051] The attitude angles of the airship platform are obtained through the IMU inertial navigation system. Let α be the roll angle around the X-axis, β be the pitch angle around the Y-axis, and γ be the heading angle around the Z-axis.

[0052] The real-time location L of the airship platform was obtained using a GNSS global positioning system. A =(L Ax L Ay L Az ) T .

[0053] First, consider the influence of the beam orientation on velocity measurement. The direction of the pulsed beam can be represented as a vector in the coordinate system of the airship platform. Where τ is the echo time, c is the speed of light, and x0 is defined in a normalized manner. 2 +y0 2 +z0 2 =1. In the forward-conical scanning mode, the characteristics of the pulse beam are known. here It is a semi-cone angle.

[0054] The direction of the pulse beam is a vector in the geodetic coordinate system. Similarly, normalization is applied to define x1 2 +y1 2 +z1 2 =1. This can be represented by a rotation matrix: P′ = RP. The rotation matrix is ​​represented as:

[0055]

[0056] Then, consider the impact of the aerostat platform's own motion on velocity measurement. The aerostat platform's own motion will affect the wind speed relative to the platform, thus affecting wind measurement according to the Doppler principle. The position L of the aerostat platform... A The velocity v of the platform is obtained by differentiation. A =(v Ax v Ay v Az ) T .

[0057] Assume the wind speed is v w =(v wx v wy 0) T The relative velocity of the wind direction to be measured relative to the airship platform can be expressed as:

[0058] v R1 =(v wx -v Ax v Wy -r Ay -v Az ) T

[0059] The expression for the relative radial wind speed is obtained by projecting the relative velocity of the wind direction to be measured relative to the airship platform onto the direction of the pulse beam:

[0060] V = (v wx -v Ax )x1+(v wy -v Ay )y1-v Az z1

[0061] When V ＞A frequency shift of Δf < 0 indicates that the relative radial wind speed is in the same direction as the emitted light, meaning the wind is moving away from the aerostat, resulting in a frequency shift Δf > 0. When V < 0, it indicates that the relative radial wind speed is in the opposite direction to the emitted light, meaning the wind is moving towards the aerostat, resulting in a frequency shift Δf > 0. The frequency shift obtained by the laser detector is Δf. According to the Doppler principle, the relative radial velocity expressed in terms of frequency shift is:

[0062]

[0063] In the formula, c is the speed of light, and f0 is the laser frequency. This is the equation for retrieving the wind field using Doppler frequency shift. This equation contains two unknowns, namely v Ax and v Ay Therefore, in a single measurement mode, two beams of light are required to establish a system of two equations.

[0064] Furthermore, the motion compensation method provided in this embodiment considers that the height information of the wind field to be measured is affected by both the beam azimuth and the platform motion. The measured height is determined using GNSS height information, beam direction in the geodetic coordinate system, and echo time, including:

[0065] S550, calculate half the product of the echo time and the speed of light of the pulse beam, and multiply it by the height of the pulse beam per unit length in the geodetic coordinate system to obtain the height compensation value.

[0066] S560 calculates the sum of the height compensation value and the height of the airship platform in the geodetic coordinate system to obtain the height of the wind field to be measured.

[0067] The expression for the height of the wind field to be measured is:

[0068]

[0069] Where Z represents the height of the wind field to be measured, τ is the echo time, c is the speed of light, z1 is the height of the pulse beam per unit length in the geodetic coordinate system, and L Az The height of the airship platform.

[0070] Those skilled in the art will understand that the features described in the various embodiments and / or claims of this disclosure can be combined or combined in various ways, even if such combinations or combinations are not explicitly described in this disclosure. In particular, the features described in the various embodiments and / or claims of this disclosure can be combined or combined in various ways without departing from the spirit and teachings of this disclosure. All such combinations and / or combinations fall within the scope of this disclosure.

[0071] Although this disclosure has been shown and described with reference to specific exemplary embodiments thereof, those skilled in the art will understand that various changes in form and detail may be made to this disclosure without departing from the spirit and scope of the disclosure as defined by the appended claims and their equivalents. Therefore, the scope of this disclosure should not be limited to the above embodiments, but should be defined not only by the appended claims, but also by their equivalents.

Claims

1. A lightweight laser wind-measuring radar device for an aerostat platform, characterized in that, include: A laser light source used to generate pulsed beams with preset energy and preset frequency; The transceiver optical system includes a stepped wedge mirror disposed on the exit path of the pulse beam, for transmitting the pulse beam in a forward conical scanning mode and receiving the echo signal of the pulse beam; The stepped wedge includes a central ordinary wedge and a stepped wedge. The central ordinary wedge is inserted into the through hole in the center of the stepped wedge, and its bottom surface is in the same plane as the bottom surface of the stepped wedge. Its inclined surface extends out of the through hole. The upper surface of the stepped wedge mirror is provided with multiple parallel steps, the steps are of the same height, and one side of the step is aligned with the direction and angle of the inclined surface of the central ordinary wedge mirror. A laser detector is positioned on the incident path of the echo signal after it passes through the transceiver optical system, and is used to detect the echo signal and obtain the frequency shift of the echo signal. The processor, connected to the laser detector, is used to calculate the velocity of the airship platform based on the real-time position information of the airship platform, and to obtain an expression for the relative velocity of the wind field to be measured relative to the airship platform based on the velocity of the airship platform. Based on the attitude of the airship platform, the azimuth of the pulse beam in the geodetic coordinate system is calculated; By projecting the relative velocity onto the orientation of the pulse beam in the geodetic coordinate system, an expression for the relative radial velocity is obtained. as well as The wind field to be measured is inverted based on the expression for the relative radial velocity and the frequency shift of the echo signal.

2. The apparatus according to claim 1, characterized in that, Also includes: A controller is used to control the rotation of the stepped wedge mirror, causing the pulse beam to deflect at an angle and converge.

3. The apparatus according to claim 1, characterized in that, The pulsed beam is emitted from the central ordinary wedge mirror.

4. A motion compensation method for a lightweight laser wind-measuring radar device for an airship platform, applied to the device as described in any one of claims 1 to 3, characterized in that, include: The velocity of the airship platform is calculated based on its real-time position information, and an expression for the relative velocity of the wind field to be measured relative to the airship platform is obtained based on the velocity of the airship platform. Based on the attitude of the airship platform, the azimuth of the pulse beam generated by the lightweight laser wind radar device on the airship platform in the geodetic coordinate system is calculated. By projecting the relative velocity onto the orientation of the pulse beam in the geodetic coordinate system, an expression for the relative radial velocity is obtained. The wind field to be measured is inverted based on the expression for the relative radial velocity and the frequency shift of the echo signal of the pulse beam.

5. The method according to claim 4, characterized in that, The expression for calculating the velocity of the airship platform based on its real-time position information, and obtaining the expression for the relative velocity of the wind field to be measured relative to the airship platform based on its velocity, includes: The real-time location information of the airship platform is obtained based on the GNSS global positioning system; The speed of the airship platform is obtained by differentiating the real-time location information. The wind speed of the wind field to be measured is preset, and the difference between the wind speed of the wind field to be measured and the speed of the airship platform is calculated to obtain the expression for the relative speed.

6. The method according to claim 4, characterized in that, The calculation of the azimuth of the pulse beam generated by the lightweight laser wind radar device on the airship platform in the geodetic coordinate system, based on the attitude of the airship platform, includes: The attitude angles of the airship platform are obtained through the IMU inertial navigation system; The azimuth of the pulse beam in the coordinate system of the airship platform is obtained, and the azimuth of the pulse beam is converted to the geodetic coordinate system based on the attitude angle of the airship platform.

7. The method according to claim 4, characterized in that, The step of inverting the wind field to be measured based on the expression for the relative radial velocity and the frequency shift of the echo signal of the pulse beam includes: The relative radial velocity is represented by the frequency shift of the echo signal according to the Doppler principle; The wind speed of the wind field to be measured is obtained by solving the expression for the relative radial velocity represented by the frequency shift.

8. The method according to claim 4, characterized in that, include: Calculate half the product of the echo time and the speed of light of the pulse beam, and multiply it by the height of the pulse beam per unit length in the geodetic coordinate system to obtain the height compensation value; The height of the wind field to be measured is obtained by calculating the sum of the height compensation value and the height of the airship platform in the geodetic coordinate system.

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