A space-borne horizontal two-dimensional wind field interferometer based on annular field of view and a full-link simulation method

Abstract

This invention discloses a spaceborne near-space horizontal two-dimensional wind field interferometric imager based on a ring field of view and a full-link simulation method. The imager includes an optical system, a detector, and a data processing unit. The optical system includes a front conical mirror, a field stop, a collimating lens group, a Fabry-Perot interferometer, a narrowband filter assembly, and an imaging lens arranged sequentially along the optical path. This invention improves the spatiotemporal resolution of the instrument's detection.

Description

Technical Field

[0001] This invention relates to the field of near-space satellite remote sensing technology, and in particular to a spaceborne near-space horizontal two-dimensional wind field interferometric imager based on a ring field of view and a full-link simulation method. Background Technology

[0002] Currently, satellite remote sensing of near-space environmental parameters all employs passive optical remote sensing technology. Based on the influence of changes in background atmospheric conditions on the spectral characteristics and radiation properties of various atmospheric components, it utilizes techniques such as spectral analysis, optical interferometry, and imaging to acquire relevant spectral and radiation parameters, thereby retrieving near-space environmental parameters. From the perspective of satellite remote sensing observation modes, it can be divided into two categories: edge observation and nadir observation. Edge observation remains the mainstream, mainly focusing on techniques such as fine spectral dispersion, spectral imaging thermometry, and interferometric wind measurement. Typical satellite payloads include WINDII / UARS, TIDI / TIMED, SOFIE / AIM, and MIGHTI / ICON. The advantage of edge observation is that it can provide high vertical resolution (0.5~2km), finely detecting changes in atmospheric composition with altitude. However, its disadvantages are equally obvious: its horizontal coverage is narrow, consisting of a single field of view, lacking horizontal resolution perpendicular to the line of sight, and data inversion requires the assumption of a uniform distribution of components across all layers.

[0003] In contrast, nadir observation modes offer significant advantages. With appropriate target selection, they possess extremely high horizontal two-dimensional spatiotemporal resolution and wide coverage, making them the optimal tool for studying small- and medium-scale dynamic processes and energy transfer coupling. However, due to the extremely thin atmosphere in near-space, the radiation of most observable components is extremely weak. Using traditional airglow visible and near-infrared light as light sources, it is impossible to achieve a high signal-to-noise ratio with short exposure times, while longer exposure times result in severe image shift due to the satellite's inherent orbital speed of ~7.6 km / s. Furthermore, existing interferometric wind measurement techniques, designed to improve image signal-to-noise ratio, are all single-field-of-view, enabling only single-point or scanning area detection, and cannot achieve large-scale, high-spatiotemporal resolution detection. Therefore, they cannot achieve refined detection within a horizontal two-dimensional plane, hindering the study of small-scale dynamic processes in near-space. Summary of the Invention

[0004] Purpose of the Invention: The purpose of this invention is to provide a spaceborne near-space horizontal two-dimensional wind field interferometric imager based on a ring field of view and a full-link simulation method. It employs a satellite nadir observation mode and utilizes FPI optical interferometric imaging technology to detect radial wind speeds along the line of sight of the ring field of view. By manipulating the satellite, multiple ring fields of view overlap, and a high-resolution gridding algorithm is used to synthesize the radial wind speeds from multiple lines of sight within the overlapping area into a horizontal two-dimensional vector wind field. Simultaneously, a full-link simulation method is provided to simulate satellite-detected images under a preset wind field, invert the horizontal two-dimensional wind field, and evaluate the error level, thus addressing the problems existing in the background technology.

[0005] Technical Solution: The present invention discloses a spaceborne near-space horizontal two-dimensional wind field interferometric imager based on a ring field of view, comprising an optical system, a detector, and a data processing unit. The optical system includes a front conical mirror, a field stop, a collimating lens group, a Fabry-Perot interferometer, a narrowband filter assembly, and an imaging lens arranged sequentially along the optical path. The front conical mirror has its conical surface facing the incident light direction and its tip pointing towards the detector side, used to reflect and converge large-angle incident radiation from the target aeroglow to the field stop, forming a ring-shaped observation field of view corresponding to the cone angle of the conical mirror. The collimating lens group converts the diverging beam exiting the field stop into a circular field of view. A parallel beam is incident on the Fabry-Perot interferometer; the Fabry-Perot interferometer performs multi-beam equal-inclination interference on the parallel beam, converting the Doppler frequency shift in the line-of-sight direction into a radial position change of the interference rings; the detector receives the interference light signal converged by the imaging lens and generates an interference image; the data processing unit inverts the radial wind speed in the corresponding line-of-sight direction based on the radial offset of the interference rings in different azimuth intervals of the interference image obtained from a single exposure, and uses the overlapping relationship of the annular field of view generated by multiple exposures during satellite motion to obtain the horizontal two-dimensional wind field distribution of the target aeroglow by synthesizing the radial wind speed vectors in different line-of-sight directions in the overlapping area.

[0006] Furthermore, the apex angle of the conical cross-section of the front conical reflector is set so that the incident light forms a circular coverage area at the height of the target gasgloss after one reflection. The field of view depression angle of the circular coverage area is close to a fixed value, so that the radial wind speed information of the line of sight around the star can be obtained in a single exposure. The reflective surface of the front conical reflector is coated with an infrared band anti-reflection film, and the front conical reflector is fixedly connected to the outer edge of the field stop through a transparent lens tube.

[0007] Furthermore, the narrowband filter assembly includes an electric filter wheel and a narrowband filter mounted on the electric filter wheel. The center wavelength of the narrowband filter corresponds to the characteristic spectral line of OH gas glow in the short-wave infrared region, which can obtain a radiation intensity higher than that of the traditional near-infrared spectral band and shorten the time required for a single exposure. The narrowband filter assembly is also equipped with a temperature control device to stabilize the operating temperature of the narrowband filter in order to maintain the stability of the filter center wavelength.

[0008] Furthermore, the detector is a scientific-grade deep-cooled array detector, with its photosensitive chip located at the focal plane of the imaging lens, and the photosensitive material's response band covering the selected characteristic spectral lines of the narrowband filter component.

[0009] Furthermore, the data processing unit divides the interferometric image into multiple sector-shaped analysis regions along the circumference, performs circumferential integration and peak position fitting on the interferometric rings within each sector region, and obtains the radial wind speed in the direction of the line of sight at that azimuth by comparing it with the windless reference peak position; the data processing unit performs geometric correction on the radial velocity component generated by the satellite motion, based on the real-time position of the satellite orbit, the velocity vector, and the azimuth and depression angles of the instrument's observation lines projected onto the ground; the data processing unit identifies the overlapping positions of the annular field of view in the airglow at different exposure times, extracts at least two radial wind speed observations from different exposure times and different azimuth angles of the field of view at each overlapping position, and calculates the horizontal two-dimensional wind speed vector at the overlapping position through vector synthesis.

[0010] The present invention discloses a full-link simulation method for a spaceborne near-space horizontal two-dimensional wind field interferometric imager, comprising the following steps:

[0011] (1) Constructing an atmospheric scene: Based on the atmospheric background model, wind field model and gasglow photochemical radiation model, a comprehensive atmospheric scene is constructed, which includes the three-dimensional wind field spatial distribution and the target gasglow body emissivity spatial distribution. The three-dimensional wind field spatial distribution supports the configuration of multiple preset wind field modes. Among them, the multiple preset wind field modes include a uniform wind field mode, a wind field mode with random disturbances, a wind field mode with horizontal wind shear, and a wind field mode with gravity wave disturbances.

[0012] (2) Calculate radiation transfer: For the airglow radiation generated by the target airglow layer in the integrated atmospheric scene, the radiation transfer is calculated along the atmospheric path from the target airglow layer to the entrance pupil of the instrument, and the entrance pupil radiation energy distribution is obtained after considering path attenuation and scattering effects.

[0013] (3) Instrument and platform coupling simulation: Obtain the optical system parameters of the imager, the response characteristic parameters of the detector and the orbital motion parameters of the satellite platform, and couple the entrance pupil radiation energy distribution with the optical transmission characteristics of the imager, the photoelectric conversion characteristics of the detector and the line of sight geometry caused by the satellite motion to generate a simulated interference image.

[0014] (4) Inversion Calculation and Error Analysis: Inversion calculation is performed on the simulated interferometric image to obtain the inverted horizontal two-dimensional wind field; including circumferential partitioning of the simulated interferometric image, extraction of radial peak positions of the interferometric ring, geometric correction of satellite velocity, pairing vector synthesis of line-of-sight wind speed in the overlapping area of ​​multiple exposures, and gridded wind field reconstruction of the target airglow layer. The inverted horizontal two-dimensional wind field is compared point by point with the preset real wind field in the constructed comprehensive atmospheric scene in the same spatial coordinate system. The deviation distribution and error statistics of wind speed components, wind direction angle and total wind speed are statistically analyzed, and the error evaluation results are output.

[0015] (5) Parameter sensitivity analysis and optimization adjustment: Based on the output error evaluation results, the optical system parameter configuration, single exposure time control strategy and satellite orbit observation scheme of the imager are analyzed for sensitivity, and the imager parameters and observation scheme are optimized and adjusted based on the analysis results;

[0016] Furthermore, in step (3), when generating the simulated interferometric image, a noise model related to the detector's operating state is introduced; wherein the noise model includes dark current noise and readout noise;

[0017] Further, the inversion calculation in step (4) is as follows: the simulated interferometric image is divided into multiple fan-shaped analysis regions along the circumference, and the radial signal distribution curve is obtained by radial ring integration of the interferometric rings in each fan-shaped region; the radial signal distribution curves are numerically fitted by an asymmetric linear function, and the radial peak position coordinates of the interferometric rings are determined with sub-pixel accuracy; the radial component correction of the peak position offset of each line of sight is performed according to the real-time position and velocity vector of the satellite orbit; the spatial overlap position of the ring field of view generated by multiple exposures on the ground is identified, and two radial wind speed observations from different exposure times and different azimuth angles of the same overlap position are extracted and vector synthesized; a regular spatial grid of the target airglow layer is established according to the minimum spatial resolution of the imager, and the wind vectors obtained by solving the overlap position are assigned to the corresponding grid cells according to spatial affiliation, and multiple wind vectors in the same grid cell are averaged to generate a gridded inverted wind field.

[0018] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages:

[0019] 1. The spaceborne near-space horizontal two-dimensional wind field interferometric imager based on a ring field of view proposed in this invention adopts a multi-ring field of view overlapping detection mode based on nadir observation. It can detect the radial wind speed in the line of sight of the ring field of view. By performing gridded appropriate wind inversion on the multi-line of sight data at the overlapping of the fields of view, it can obtain a global coverage, high spatiotemporal resolution near-space horizontal two-dimensional wind field. It is of great significance for small-scale dynamics research in near space and safety assurance of near-space spacecraft.

[0020] 2. The spaceborne near-space horizontal two-dimensional wind field interferometric imager based on a ring field of view proposed in this invention uses a conical mirror to replace the optomechanical structure of the existing mechanical scanning mirror, and with the help of a new optical path structure design of the photometric system, the observation field of view is transformed into a ring with a certain width. The diameter of the ring is about 600km, the field of view angle is about 90°, and the ring angle width is about 2.3°. A single detection can obtain the radial wind speed of the line of sight in all directions, thus establishing a detection system with a fully static optomechanical structure.

[0021] 3. The spaceborne near-space horizontal two-dimensional wind field interferometric imager based on the annular field of view proposed in this invention uses the Q1(1) characteristic spectral line of the OH(2-0) gasglow at 1434nm in short-wave infrared as the light source target. Its radiation intensity reaches 30~50K Rayleigh, which is 50 times or even higher than the total radiation of the near-infrared P-branch spectral band of the OH(6-2) gasglow used by traditional instruments. Sufficient signal-to-noise ratio can be obtained with only a short exposure time, which can greatly improve the spatiotemporal resolution of the instrument of this invention.

[0022] 4. The full-link simulation system proposed in this invention includes 7 sub-modules. It can set up three-dimensional wind field and airglow radiation scenarios, construct a mathematical model of the instrument based on the main structure and optical parameters, calculate the propagation link of the detection signal by means of the radiation transmission in the thin atmosphere, simulate the image captured by the instrument, invert the vector wind field, evaluate the error level, and optimize the configuration and parameters of the instrument proposed in this invention through parameter sensitivity analysis to verify its feasibility for spaceborne detection. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the main optical structure of the present invention;

[0024] Figure 2 This is a schematic diagram of the electromechanical structure of the present invention;

[0025] Figure 3 This is the distribution diagram of the OH(2-0) band gasglow characteristic spectral lines used in this invention;

[0026] Figure 4 This is a schematic diagram of the nadir observation mode based on the ring field of view of the present invention;

[0027] Figure 5 This is a schematic diagram showing the overlap of the observation fields at two different locations during the on-orbit operation of the present invention;

[0028] Figure 6 This is a schematic diagram of the field of view projected onto the ground during multiple consecutive exposures in orbit according to the present invention;

[0029] Figure 7 This is a schematic diagram of the horizontal two-dimensional vector wind field inversion process of the present invention;

[0030] Figure 8 This is a schematic diagram of the horizontal two-dimensional vector wind field forward modeling process of the present invention;

[0031] Figure 9 These are schematic diagrams of the preset two-dimensional and three-dimensional wind field and airglow radiation scenarios of the present invention; Figure 9 (a) in the figure is a schematic diagram of a two-dimensional horizontal wind field scenario with disturbance. Figure 9 (b) in the figure is a schematic diagram of a three-dimensional wind field scene with disturbances;

[0032] Figure 10 This is a schematic diagram of the simulated image and the method of dividing the image into 16 partitions according to the present invention; Figure 10 Image (a) in the image is taken by the system's simulated imager. Figure 10 (b) in the figure represents the radial readout electron number profile at an azimuth angle of 185°. Figure 10 (c) in the figure is a comparison between the radial readout electron number profile at an azimuth angle of 185° and the radial readout electron number profile at zero radial wind speed at the same azimuth angle. Figure 10 (d) in the diagram is a schematic diagram of the annular field of view partition on the target airglow layer; Figure 10 (e) in the image is a close-up of the first readout electron peak and the first readout electron peak at zero radial wind speed at that azimuth angle;

[0033] Figure 11 This is the result of the wind field inversion based on a single-exposure image in a wind field scenario with disturbed wind fields, according to the present invention. Figure 11 (a) in the figure is a comparison between the inverted wind speed and direction from a single detection and the actual wind speed and direction. Figure 11 (b) in the figure is a polar coordinate comparison diagram of the radial wind speed obtained from the inversion of each sector and the actual radial wind speed. Figure 11 (c) in the figure is a scatter regression comparison of the radial wind speed obtained by inversion in each sector and the actual radial wind speed;

[0034] Figure 12 This is a schematic diagram illustrating the principle of the present invention for joint inversion of wind fields based on multiple exposure images in wind field scenarios with disturbed wind fields; Figure 12 (a) shows the overlap of the multi-measurement detection fields of view and the distribution of overlap points. Figure 12 (b) in the diagram is a schematic diagram of the principle of dual-field-of-view inversion at overlapping points. Figure 12 (c) in the middle is Figure 12 (a) Legend and schematic diagram of the line-of-sight angle partitioning method in the figure;

[0035] Figure 13 This is a diagram showing the results of the joint inversion of wind field based on multiple exposure images in a wind field scenario with disturbed wind field, according to the present invention. Figure 13 (a) in the diagram is a schematic diagram of the inverted wind speed grid. Figure 13(b) in the diagram is a schematic diagram of the inverted wind direction grid;

[0036] Figure 14 This is an error analysis diagram of the present invention for joint inversion of wind field based on multiple exposure images in wind field scenarios with disturbed wind fields; Figure 14 (a) in Figure 14 (d) in the figure represents the scatter regression plots of the inverted wind U, V, and composite wind speed and direction, respectively. Figure 14 (e) in Figure 14 The (h) diagrams in the diagram represent the error distribution of the inverted wind U, V, and the synthesized wind speed and direction, respectively.

[0037] In the diagram: 1. Front conical mirror, 2. Quartz glass tube, 3. Field stop, 4. Light-shielding tube, 5. Large-aperture cemented doublet lens, 6. Fabry-Perot interferometer, 7. Narrow-band filter, 8. Motorized filter wheel, 9. TEC precision temperature controller, 10. Imaging fixed-focus lens, 11. InGaAs sensor chip, 12. Scientific-grade depth-cooled camera, 13. External light-shielding ring assembly, 14. Regulated power supply, 15. Micro industrial computer, 16. Three-axis electronic compass, 17. Tube clamp, 18. CNC machined housing, 19. PDU programmable power supply, 20. TEC semiconductor temperature controller, 21. Instrument connection bracket, 22. Aviation connector. Detailed Implementation

[0038] The technical solution of the present invention will be further described below with reference to the accompanying drawings. It should be understood that the following specific embodiments are only used to illustrate the present invention and are not intended to limit the scope of protection of the present invention.

[0039] like Figure 1As shown, an embodiment of the present invention provides a spaceborne near-space horizontal two-dimensional wind field interferometric imager based on a ring field of view. Specifically, it is designed with a front conical reflector 1, with its bottom surface facing upwards and its tip downwards. The reflector is made of quartz glass with a gold-plated surface to enhance infrared reflectivity. The cross-sectional angle of the conical reflector can be set between 35° and 55°, typically around 45°. The tip of the front conical reflector 1 is located at the center of the optical plane of the field stop 3. A high-transparency quartz glass tube 2 connects the bottom surface of the front conical reflector 1 to the outer wall of the field stop 3, forming a surrounding enclosure and supporting the front conical reflector 1. The end of the field stop 3 is tightly connected to a light-shielding tube 4. A large-aperture cemented doublet lens 5 is disposed inside the light-shielding tube 4, at a distance of one focal length below the center of the field stop 3. The purpose of this lens is to collimate the diverging beam emitted from the field stop 3, converting the emitted light into a parallel beam. A Fabry-Perot interferometer 6 is installed 5-10 mm behind a large-aperture cemented doublet lens 5 and tightly connected to a light-shielding lens tube 4. This interferometer is a multi-beam interferometer with extremely high spectral resolution, consisting of two parallel circular flat glass plates coated with a high-reflectivity film. It can perform equal-inclination interference processing on parallel incident beams, achieving optical resolution of the small Doppler frequency shift of characteristic spectral lines. The output end of the Fabry-Perot interferometer 6 is tightly connected to an electric filter wheel 8. The electric filter wheel 8 generally contains 3-5 apertures, which can be fitted with narrowband filters 7 to filter out specific wavelength beams that meet the measurement requirements, ensuring the purity of the interference signal and the measurement accuracy. Infrared light-shielding plates and black light-shielding plates can also be installed in the apertures of the electric filter wheel 8 for in-machine calibration of key instrument parameters. A TEC precision temperature controller 9 is used to precisely control the temperature of the electric filter wheel 8 and the narrowband filter 7 inside it, ensuring the stability of the filtering effect of the narrowband filter 7. The motorized filter wheel 8 is tightly connected at its exit end to the imaging fixed-focus lens 10, and at its end to the scientific-grade depth-cooled camera 12 via a lens mount. The scientific-grade depth-cooled camera 12 employs TEC depth-cooling technology, which can reduce the temperature to an extremely low level (-70°C) to reduce dark current noise. It integrates an InGaAs sensor chip 11, which is an array detector precisely located on the focal plane of the imaging lens. This InGaAs sensor chip 11 can efficiently capture the interferometric light signal and convert it into an electrical signal.

[0040] like Figure 1As shown, the optical path principle of the imager described in this invention is as follows: A light beam radiated from the near-space aeroglow layer, after radiative transmission along the atmospheric path, enters the front end of the instrument. First, it is reflected by the front conical mirror 1 and converges on the optical plane of the field stop 3, forming the object plane. Then, it enters the light-shielding tube 4 in the form of diverging light. When the light enters the large-aperture cemented doublet lens 5, it is collimated into a parallel beam and enters the Fabry-Perot interferometer 6. After optical interference, it exits the Fabry-Perot interferometer 6 and is then filtered by the narrow-band filter 7 on the motorized filter wheel 8. The filtered target spectral line narrow-band beam is converged by the imaging fixed-focus lens 10 and finally strikes the InGaAs sensor chip 11, forming a ring interference image. After this optical structure processing, the field of view of one pixel on the InGaAs sensor chip 11 can cover a region of the target aeroglow layer with an angular width of 2.3°. When the transverse cone angle of the front conical reflector 1 is set to 45°, under its reflection, the field of view of all pixels can cover a ring with a diameter of about 600 km and a width of 16 km on the target aeroglow.

[0041] like Figure 2 As shown, the electromechanical structure of the imager of this invention is as follows: an external light-shielding ring group 13 is securely mounted on the top of the CNC-machined housing 18. Its function is to eliminate the influence of stray light incident outside the field of view on the detection by continuously reflecting and attenuating stray light in the ring group. Its central optical axis is coaxial with the center of the light-shielding lens tube 4. A regulated power supply 14, a micro industrial control computer 15, and a PDU programmable power supply 19 are securely mounted on the side wall of the CNC-machined housing 18. The regulated power supply 14 is connected to an external power source by an aviation plug 22 embedded in the bottom of the side plate of the CNC-machined housing 18, and provides a regulated DC power to the micro industrial control computer 15 and the PDU programmable power supply 19. The micro industrial control computer 15 controls the power on and off of the three sockets of the PDU programmable power supply 19 through relevant software. The three sockets on the PDU programmable power supply 19 respectively power the scientific-grade depth-cooled camera 12, the TEC semiconductor temperature controller 20, and the TEC precision temperature controller 9, thereby ultimately realizing the purpose of the micro industrial control computer 15 to control the key components of the instrument. The TEC precision temperature controller 9 is used to precisely control the temperature of the electric filter wheel 8 and its internal narrowband filter 7, ensuring the stability of the filtering effect of the narrowband filter 7. The TEC semiconductor temperature controller 20 controls the overall temperature of the instruments inside the CNC machining housing 18 to remain constant, ensuring the normal operation of each instrument. The three-axis electronic compass 16 is directly powered by the regulated power supply 14 and locates the XYZ axis offset position of the positioning satellite in real time, so as to provide accurate angle positioning information for wind speed inversion. Figure 1 The main optical system structure of the instrument shown consists of multiple lens barrel clamps 17 fixed to the instrument connecting bracket 21, while the instrument connecting bracket 21 is fixed to the back plate inside the CNC machined housing 18, thus forming a complete and sturdy instrument as a whole.

[0042] like Figure 3 As shown, this invention uses the Q1(1) characteristic spectral line of the OH(2-0) gas glow at 1434 nm in the short-wave infrared as the light source target. Nearby interfering spectral lines are few and have low intensity; the target spectral line can be accurately screened through specific filter design. Its radiation intensity peak reaches 30~50 K Rayleigh, which is 50 times or even higher than the total radiation of the near-infrared P-branch spectral band of the OH(6-2) gas glow used in traditional instruments. Sufficient signal-to-noise ratio can be obtained with a shorter exposure time, significantly improving the spatiotemporal resolution of the instrument's detection while reducing the image shift caused by satellite motion. Figure 3 As shown, the red line represents the response curve of the instrument's filter, and the blue line represents the position and intensity of each emission spectral line of OH. This invention uses the Q1(1) characteristic spectral line of the OH(2-0) gas glow at 1434 nm in the short-wave infrared as the light source target. Nearby interfering spectral lines are few and have very low intensity; through specific filter design, the target spectral line can be accurately selected. Its radiation intensity peak reaches 30~50 K Rayleigh, which is 50 times or even higher than the total radiation of the near-infrared P-branch spectral band of the OH(6-2) gas glow used in traditional instruments. Sufficient signal-to-noise ratio can be obtained with a shorter exposure time, significantly improving the spatiotemporal resolution of the instrument's detection while reducing the image shift caused by satellite motion.

[0043] like Figure 4 As shown, the target airglow layer observed in this invention is located at an altitude of approximately 87 km above the Earth, with a thickness of about 3-5 km. At this altitude, it is generally believed that the collision frequency between molecules is sufficient to keep the relatively low rotational energy level airglow OH molecules in a state of local thermodynamic equilibrium. According to the principle of the Doppler effect, when there is a wind field in the atmosphere, the motion of airglow OH particles will cause a slight shift in the wavelength of the radiation spectrum, i.e., a Doppler shift Δλ, which can be expressed as:

[0044] ;

[0045] Where λ0 = 1434 nm is the spectral wavelength at rest, and v wind,los To observe the wind speed along the line of sight, it can be expressed as:

[0046] ;

[0047] Where θ is the azimuth angle of the line of sight, and φ is the depression angle of the line of sight.

[0048] Since this invention is a spaceborne instrument, the wavelength shift Δλ caused by satellite motion also needs to be considered during the inversion process. ’ ,Right now:

[0049]

[0050] The total radial velocity Radial wind speed Subtract the radial component of the satellite's velocity ,Right now:

[0051]

[0052]

[0053] φ represents the direction of satellite flight.

[0054] This wavelength shift is amplified by the Fabry-Perot interferometer 6 and ultimately reflected in the local radius change of the bright ring on the InGaAs sensor chip 11. When the satellite conducts nadir observations of the airglow, due to the effect of the forward conical reflector 1 (with a cross-sectional cone angle set to 45°), the area covered by the instrument's field of view on the target airglow will be circular, with a diameter of approximately 600 km and a field of view angle of 90°. At this time, the depression angle of the target airglow observed by the spaceborne horizontal two-dimensional wind field interferometric imager is... Therefore, the satellite can obtain the Doppler frequency shift in all directions (0~360°) along the line of sight of the conical surface in a single exposure.

[0055] like Figure 5 As shown, when the instrument of this invention travels in orbit with the satellite at a speed of 7.6 km / s, it completes two observations of the target airglow, with the time interval between the two observations being the exposure time. By controlling the exposure time, the distance between the centers of the annular fields of view of the two observations is precisely controlled, so that the annular fields of view of the two observations intersect on the target airglow, generating an overlap point. A pair of radial wind speed data from the two detections are used for vector synthesis, and then the wind speed and direction of the overlap point are synthesized and inverted. According to the principle of vector synthesis, when the radial wind speeds obtained from the two detections are orthogonal, the wind speed and direction inverted by vector synthesis are closest to the true wind speed and direction. For the instrument to accurately invert the true wind speed and direction of the overlap point, the two radial wind speeds used to invert the true wind speed and direction of the overlap point must be as orthogonal as possible, that is, the angle between the projections of the lines of sight through the overlap point onto the target airglow needs to be close to 90°. By controlling the exposure time, the instrument can make the angle between the projections of the lines of sight through the overlap point within a certain range (30°~150°) close to 90°, thereby significantly improving the accuracy of the inversion.

[0056] like Figure 6 As shown, the spaceborne near-space horizontal two-dimensional wind field interferometric imager based on a ring field of view of the present invention performs multiple detections during satellite flight, and the ring field of view of the multiple detections (such as...) Figure 6 The circular ring shown follows the trajectory of the satellite's nadir point (as shown in the image). Figure 6(Solid lines shown) are arranged sequentially. As the satellite travels along its orbit, each probe acquires the Doppler frequency shift at various locations on the rings, thus calculating the radial velocity. After time-series probes, numerous overlapping regions are found between the rings, generating a large number of spatial overlap points on the target airglow. For each overlap point, there are two radial velocities observed from different perspectives. These two radial velocity observations from different directions can form a system of equations, which, through vector synthesis, can be solved to deduce the true two-dimensional horizontal wind speed vector at that overlap point. The satellite continues to probe while traveling along its orbit, and the numerous overlap points between the rings are continuously distributed along the satellite's nadir trajectory. Each overlap point can independently calculate the aforementioned two-dimensional wind vector, thus forming a series of high-precision two-dimensional wind speed and direction datasets distributed along the satellite's nadir trajectory (e.g., ...). Figure 6 As shown, the dashed line passing through the intersection point is the connection line of one of the datasets in space. By adjusting the satellite's orbital inclination, the high-resolution, high-precision two-dimensional wind field data retrieved in each orbital period will be continuously stitched together in space, ultimately achieving comprehensive detection and reconstruction of the high-resolution, high-precision two-dimensional wind field at the airglow height of near-space targets worldwide.

[0057] like Figure 7 As shown, the inversion process of the spaceborne near-space horizontal two-dimensional wind field interferometric imager based on a ring field of view according to the present invention is as follows:

[0058] Step 1: The raw image data processed by the optical system is input into the computer system for noise reduction. The denoised interferometric image is divided into 16 equally sized sectors, each corresponding to an arc-shaped region of the annular field of view on the target gas glow layer. Circular integration is performed within each sector. Using the side length of the 11 pixels of the InGaAs sensor chip as the unit length of the abscissa and the number of readout electrons after circumferential integration as the ordinate, 16 schematic diagrams are drawn showing the radially distributed data point sets of the readout electron count after circumferential integration.

[0059] Step 2: Using a slanted Voigt curve, fit the data points of the 16 readout electron counts after circumferential integration along the radial distribution. Record the peak positions of the fitted curves for each curve, forming a dataset of peak positions in 16 directions. Using the fitted curves to find the brightness peaks allows the instrument to detect shifts smaller than 11 pixels in the InGaAs sensor chip. Compared to directly using discrete data from the radially distributed data points of the readout electron counts after integration to determine the brightness peak position, this method has smaller errors and can effectively improve the accuracy of the inversion.

[0060] Step 3: The computer system will simulate the standard omnidirectional readout electron count continuous curve data under windless conditions based on the set radiation parameters, radiation transfer parameters, instrument parameters and experimental test data, and record the peak position to form a control dataset.

[0061] Step 4: Compare the detection dataset with the control dataset to obtain the radial abscissa drift of the readout electron number peaks in 16 directions. Combine the instrument parameters of the spaceborne near-space horizontal two-dimensional wind field interferometer imager based on the annular field of view and the principle of the Doppler effect to invert the dataset of radial wind speed detection results in 16 directions.

[0062] Step 5: By reading the real-time TLE data from the two lines of satellite orbit, the orbital position and velocity in the XYZ axes are calculated in real time to accurately obtain the satellite's operating speed, direction, and attitude, thereby correcting the radial velocity offset caused by the satellite's motion in 16 directions.

[0063] Step 6: As the satellite travels along its orbit, each probe acquires the Doppler frequency shift at various locations within the rings, allowing for the calculation of radial velocity. Following a time-series probe sequence, numerous overlapping regions are observed between the rings, generating a large number of spatial overlap points on the target airglow. For each overlap point, there are two radial velocities in different directions. These two radial velocity observations can form a system of equations, which, through vector synthesis, can be solved to deduce the true two-dimensional horizontal wind speed vector at that point. The system automatically identifies all spatial overlap points within the ring field of view, batches extracts bidirectional radial wind speed data from each point, and completes joint calculations, providing complete two-dimensional wind field foundation data for subsequent gridded wind field reconstruction.

[0064] Step 7: After completing the two-dimensional wind vector calculation at each overlapping point, the system, referencing the minimum spatial resolution (i.e., the width of the ring) of the spaceborne near-space horizontal two-dimensional wind field interferometric imager based on the annular field of view of this invention, constructs a uniform spatial grid on the target airglow, with each grid of appropriate size. Wind direction and speed data at all overlapping points are mapped to the corresponding grids, and multiple wind vectors falling within the same grid are averaged to suppress the influence of observation errors. Finally, a high spatiotemporal resolution two-dimensional wind speed and direction data grid of the target airglow is output, providing a high-quality quantitative observation dataset for near-space dynamics research.

[0065] like Figure 8 As shown, the full-link simulation system flow of the spaceborne near-space horizontal two-dimensional wind field interferometric imager based on a ring field of view according to the present invention is as follows:

[0066] The forward modeling section, initiated from the input end, is divided into six steps: atmospheric scene input, emissivity calculation, radiative transfer calculation, detector mode coupling, simulated image output, and inversion program calculation. These steps proceed sequentially from top to bottom, with input parameters continuously optimized based on the output results. The specific steps are as follows:

[0067] S1 first receives statistical feature correction parameters and reads in the airglow radiation photochemical model, and then inputs atmospheric scene parameters, including atmospheric background data represented by the MSISE-00 model, AWE observation dataset, and HWM wind field dataset, to complete the comprehensive modeling of the atmospheric scene and the determination of wind field parameters.

[0068] After completing the atmospheric scene modeling, S2 proceeds to the volume emissivity calculation stage. This stage, based on the gasglow radiation photochemical model, simultaneously introduces a spatial distribution perturbation module (such as mesoscale dynamic processes like gravity waves) and combines it with the radiation intensity peak center calculation results to refine the spatial distribution of the target gasglow's volume emissivity, providing physical input for subsequent radiative transfer calculations.

[0069] S3 then calls the radiative transfer calculation module and uses multi-parameter generation tools such as MODTRAN and LBLRTM to perform a layer-by-layer accurate simulation of the attenuation, scattering and transmission process of the airglow radiation signal along the path, and outputs the radiation field distribution reaching the 3rd window of the field stop.

[0070] The results of the S4 radiative transfer calculation are entered into the detection mode coupling stage. Here, the parameters of the wind measuring instrument, as well as the satellite platform and orbit parameters, are introduced simultaneously. The radiative physical quantities are coupled with the instrument response function and the platform motion state to form a model, providing complete input conditions for the detector image simulation.

[0071] Finally, in the detector simulation image stage, S5 integrates and maps the output of all the above physical processes onto the detector imager plane to generate a simulated interference image that includes real device effects such as noise, dark current, and quantum efficiency.

[0072] The S6 simultaneously calculates and inverts the two-dimensional gridded inverted wind field from the simulated interferometric image and the standard interferometric image, and then adjusts the instrument and system parameters based on the analysis of the inverted wind field.

[0073] The inversion section starts with dual inputs of simulated and real data. Through image denoising, 16-sector partitioning and circumferential integration, oblique Voigt line fitting, and peak extraction, a probe dataset and a control dataset are formed. Then, satellite velocity correction is completed by combining real-time TLE data from satellite orbits. After joint inversion of multiple exposure data and intersection wind speed calculation, wind direction and speed are finally calibrated on the target airglow grid, outputting a high spatiotemporal resolution gridded inverted wind field. For detailed inversion procedures, please refer to [link / reference]. Figure 7 And related descriptions.

[0074] like Figure 9 As shown, in this invention, a three-dimensional layered wind field scene with uniform brightness field is provided ( Figure 9 (b) shows a disturbed 3D wind field scene, used as input for the forward model, and its corresponding 2D wind field scene diagram. Figure 9 (A) shows a two-dimensional schematic diagram of a disturbed wind field scene. All wind field scenes have a range of 1000×1000×25 and no vertical wind. The brightness parameters of the brightness field are calculated based on the actual emissivity of the gas in the target airglow layer, with a brightness range between 725 and 875R. Specific information about the two-dimensional wind field scene is as follows: Figure 9 (a) in the middle Figure 9 The perturbation wind field scenario shown in (b) simulates a southwest wind field with random perturbations in the horizontal band of the target aerogloss, with a wind speed of approximately 50 m / s (45.3 m / s for the westerly component and 21.1 m / s for the southerly component). This wind field scenario is mainly used to verify the ability of the spaceborne near-space horizontal two-dimensional wind field interferometric imager based on a ring field of view of the present invention to detect wind fields approaching real target aerogloss, and to verify its anti-interference capability.

[0075] like Figure 10 As shown, in this invention, as Figure 10 The system shown in (b) simulates a two-dimensional horizontal wind field interferometric imager based on a ring field of view in near-space, according to the set satellite orbit parameters, target airglow parameters, and instrument parameters. Figure 9 (a) in the middle Figure 9 Image (b) shows an image captured in a disturbed wind field scene. After processing by the optical structure, the radiation emitted by the target aeroglow within the field of view is interfered by the Fabry-Perot interferometer 6, transforming into a series of circular fringes, which are received by the InGaAs sensor chip 11, forming the interference image output by the system. The brightness of this image is normalized using the difference between the maximum and minimum global readout electron counts. This helps the system automatically balance the image contrast, thereby improving the stability and reliability of the system's image recognition. The analog imager, in situations such as... Figure 9 (a) in the middle Figure 9 The image obtained from the disturbed wind field scene shown in (b) is divided into 16 sector blocks to prepare for subsequent partitioned cyclic integration and fitting. The purpose of dividing the image into 16 sector blocks is as follows: The image is divided into 16 sector-shaped blocks, each sector corresponding to a segment of an arc-shaped region on the field of view ring of the target's atmospheric glow, such as... Figure 10 As shown in (a) in the figure. Figure 10 As shown in (b), circumferential integration and fitting are performed within each block to form a curve of the cumulative number of electrons as a function of the radius, as follows. Figure 10 As shown in (c) above. The curve of the cumulative number of electrons after circumferential integration versus the radius is compared with the standard curve, as shown below. Figure 10 (d) in Figure 10 As shown in (e) (where as Figure 10(e) shows a close-up of the first readout electron peak), which allows for the inversion of the radial wind speed in the corresponding arc-shaped region on the target airglow, and further inversion of the 16 arc-shaped regions centered on the sub-satellite point (e.g., Figure 10 The radial wind speed dataset shown in (a) is as follows. Figure 10 (c) Figure 10 (d) in Figure 10 As shown in (e) of the figure, this figure uses the 185° direction as an example (0° for true north) to illustrate the process of circumferential integration from the selected area to retrieve the radial wind speed of the arc-shaped region. During joint inversion, the more radial wind speed data within the dataset retrieved from a single exposure, the more numerous and accurate the vector winds used for vector synthesis, thus improving the accuracy of wind field detection and inversion. Theoretically, the more sector blocks are divided, the more radial wind speed data within the dataset retrieved from a single exposure, resulting in more accurate joint inversion. However, if a single sector block is too small, the signal-to-noise ratio after integration will be insufficient, and the readout electron count peaks will not be prominent. Dividing the image into 16 sector blocks ensures sufficient signal-to-noise ratio within each sector, provided there is enough radial wind speed data.

[0076] like Figure 11 As shown, in this invention, for example... Figure 9 (a) in the middle Figure 9 After the inversion of the disturbed wind field scenario shown in (b) was completed, the inversion results of the line-of-sight wind speed (V_los) for sector 16 of the first interferometric ring were evaluated. This set of illustrations evaluates the accuracy and robustness of the inverted wind field obtained from fitting the sector of the first interferometric ring relative to the actual disturbed wind field from three perspectives: wind vector comparison, polar coordinate distribution, and scatter regression. In the wind vector comparison diagram, as shown... Figure 11 As shown in (a), the actual wind vector and the inverted wind vector highly overlap, with the actual value being (44.8, 20.9) m / s and the inverted value being (47.2, 19.4) m / s. They exhibit extremely high consistency in both direction and amplitude, indicating that the first ring sector fitting has good overall wind field vector restoration capability and anti-interference capability. In the line-of-sight wind speed polar coordinate distribution map, as shown... Figure 11 As shown in (b), the polar coordinate curves of the actual line-of-sight wind speed and the inverted line-of-sight wind speed are in high agreement. The two curves overlap closely in all azimuth directions, reflecting the system's accurate inversion capability for the spatial distribution of line-of-sight wind speed in all directions. In the line-of-sight wind speed scatter regression plot, as shown... Figure 11 As shown in (c), the sample points of each sector are closely distributed around the 1:1 reference line, with a correlation coefficient of 0.998 and a root mean square error controlled at 2.68 m / s. The scatter points are colored by azimuth angles, showing a continuous and gradual distribution, which further confirms the numerical consistency and good anti-interference ability of the inversion results in each azimuth angle direction.

[0077] like Figure 12As shown, the principle of joint inversion of wind field based on multiple exposure images in this invention is as follows: When the satellite travels along its orbit, each detection acquires the Doppler frequency shift at various positions on the ring, thereby calculating the radial velocity. After time-series detection, there are numerous overlapping points between the rings. At each overlapping point, the radial velocities detected in two different line-of-sight directions can be obtained, thus jointly inverting the horizontal vector wind field, as shown below. Figure 12 (a) and as in Figure 12 As shown in (c), the system analyzes each overlapping point one by one, extracts the two annexes to which the overlapping point belongs, and draws rays from the overlapping point to the centers of the two annexes respectively. The angle between the two rays represents the angle of the line of sight at the overlapping point, as shown in (c). Figure 12 As shown in (b) of the diagram. The system performs graded processing on the line-of-sight angles of all overlapping points. After determining the grade to which the line-of-sight angle belongs, it extracts a pair of radial wind speed components that match the line-of-sight angle from the radial wind speed dataset of the 16 sectors of the corresponding two rings, performs vector synthesis, and calculates the two-dimensional horizontal wind speed vector at the overlapping point. Since the density of overlapping points gradually increases outward along the vertical direction of the nadir trajectory, if a uniform grade interval is used for all angles, a large number of overlapping points far from the nadir trajectory will fall into the same grade. When the system extracts radial velocity pairs for inversion, the wind information of a large number of overlapping points in the same grade will be inverted by the same pair of radial velocities, which will seriously reduce the inversion accuracy. Therefore, the system performs adaptive non-uniform graded processing on the two-ray angles of the overlapping points: each grade interval is 10° when the angle is less than 30°, each grade interval is 15° when the angle is between 30° and 60°, and each grade interval is 30° when the angle is between 60° and 180°. The gear range is appropriately widened as the line-of-sight angle increases, ensuring precise gear division for overlapping points in the near-track area while effectively preventing excessive concentration of overlapping points in a single gear in the far-track area. For detailed information on the 16-sector radial wind speed dataset, please refer to [link / reference needed]. Figure 10 Related information.

[0078] like Figure 13 As shown, preset satellite parameters, instrument exposure time, and Figure 9 (a) in the middle Figure 9 The uniform wind field scenario shown in (b) is used as input to simulate and generate a two-dimensional gridded inverted wind field of the target airglow layer (e.g., Figure 13 Figure (a) shows a schematic diagram of the inverted wind speed grid, as shown in Figure (a). Figure 13 (b) shows a schematic diagram of the inverted wind direction grid. The specific process is as follows: The system performs joint inversion on multiple exposure data according to the set satellite orbit, speed, direction, and attitude, generating multiple 16-axis datasets. Based on this, the system follows the procedure as follows: Figure 12The method described extracts the datasets from two observations, and then performs vector synthesis of the corresponding radial velocity data to obtain the wind speed and direction data at each overlapping point. Finally, based on the minimum spatial resolution of the spaceborne horizontal two-dimensional wind field interferometric imager, the target airglow is divided into grids, and the horizontal vector wind field is inverted by averaging the multiple radial velocities falling into each grid, ultimately obtaining the two-dimensional gridded inverted wind field of the target airglow.

[0079] like Figure 14 As shown, in this invention, statistics are as follows: Figure 12 The data of each grid point in the two-dimensional gridded inversion wind field of the target airglow layer shown are compared with those of... Figure 9 (a) in the middle Figure 9 (b) shows the error distribution of the westerly wind component (U component), southerly wind component (V component), wind speed, and wind direction at the corresponding location in the uniform wind field scene. This set of figures evaluates the accuracy and reliability of the gridded wind field inversion data relative to the actual observations through scatter regression and error distribution statistics. From the four key dimensions of U component, V component, wind speed, and wind direction, the inversion system demonstrates good robustness. In the scatter regression analysis, as shown... Figure 14 (a) in Figure 14 As shown in (d), the sample points are closely distributed around the 1:1 reference line, and the root mean square error (RMSE) of the overall wind speed is controlled at 1.91 m / s, while the RMSE of the wind direction is 2.26°, indicating that the inversion results have high numerical consistency. Regarding the error statistical distribution, as shown... Figure 14 (e) in Figure 14 As shown in (h), the errors of each physical quantity exhibit a clear normal distribution, with the offset center extremely close to zero. Specifically, the average offsets of the U and V components are -0.00 m / s and -0.23 m / s, respectively, the wind speed offset is -0.06 m / s, and the wind direction offset is only -0.22°. This low system offset indicates that the inversion system performs well in terms of joint inversion of wind fields using multiple circular fields of view and in terms of anti-interference capabilities.

Claims

1. A spaceborne near-space horizontal two-dimensional wind field interferometric imager based on a ring field of view, characterized in that, The system includes an optical system, a detector, and a data processing unit. The optical system comprises a front conical mirror, a field stop, a collimating lens group, a Fabry-Perot interferometer, a narrowband filter assembly, and an imaging lens, arranged sequentially along the optical path. The front conical mirror has its conical surface facing the incident light direction and its tip pointing towards the detector. It reflects and converges large-angle incident radiation from the target aeroglow to the field stop, forming a ring-shaped observation field corresponding to the conical angle of the mirror. The collimating lens group converts the diverging beam exiting the field stop into a parallel beam, which is then incident on the Fabry-Perot interferometer. The Brie-Perot interferometer performs multi-beam equal-inclination interference on parallel beams, converting the Doppler frequency shift in the line-of-sight direction into radial position changes of the interference rings. The detector receives the interference light signals converged by the imaging lens and generates an interference image. The data processing unit inverts the radial wind speed in the corresponding line-of-sight direction based on the radial offset of the interference rings in different azimuth intervals of the interference image obtained from a single exposure. It also utilizes the overlapping relationship of the annular field of view generated by multiple exposures during satellite motion to obtain the horizontal two-dimensional wind field distribution of the target aeroglow by synthesizing radial wind speed vectors in different line-of-sight directions in the overlapping region.

2. The spaceborne near-space horizontal two-dimensional wind field interferometric imager based on a ring field of view according to claim 1, characterized in that, The apex angle of the cone cross-section of the front conical reflector is set so that the incident light forms a circular coverage area at the height of the target aeroglow after one reflection. The field of view depression angle of the circular coverage area is close to a fixed value, so that the radial wind speed information of the line of sight around the star can be obtained in a single exposure. The reflective surface of the front conical mirror is coated with an infrared anti-reflection film, and the front conical mirror is fixedly connected to the outer edge of the field stop through a transparent lens tube.

3. The spaceborne near-space horizontal two-dimensional wind field interferometric imager based on a ring field of view according to claim 1, characterized in that, The narrowband filter assembly includes an electric filter wheel and a narrowband filter mounted on the electric filter wheel. The center wavelength of the narrowband filter corresponds to the characteristic spectral line of OH gas glow in the short-wave infrared region, which can obtain a radiation intensity higher than that of the traditional near-infrared band and shorten the time required for a single exposure. The narrowband filter assembly is also equipped with a temperature control device to stabilize the operating temperature of the narrowband filter in order to maintain the stability of the filter center wavelength.

4. A spaceborne near-space horizontal two-dimensional wind field interferometric imager based on a ring field of view according to claim 1, characterized in that, The detector is a scientific-grade deep-cooled array detector, with its photosensitive chip located at the focal plane of the imaging lens, and the photosensitive material's response band covering the characteristic spectral lines selected by the narrowband filter assembly.

5. A spaceborne near-space horizontal two-dimensional wind field interferometric imager based on a ring field of view according to claim 1, characterized in that, The data processing unit divides the interferometric image into multiple sector-shaped analysis regions along the circumference. It performs circumferential integration and peak position fitting on the interferometric rings within each sector region, and obtains the radial wind speed in the azimuth line-of-sight direction by comparing it with the windless reference peak position. The data processing unit performs geometric correction on the radial velocity component generated by the satellite motion, based on the real-time position of the satellite orbit, the velocity vector, and the azimuth and depression angles of the instrument's observation lines projected onto the ground. The data processing unit identifies the overlapping positions of the annular field of view in the airglow at different exposure times, extracts at least two radial wind speed observations from different exposure times and different azimuth angles of the field of view at each overlapping position, and calculates the horizontal two-dimensional wind speed vector at the overlapping position through vector synthesis.

6. A full-link simulation method for a spaceborne near-space horizontal two-dimensional wind field interferometric imager, characterized in that, Includes the following steps: (1) Constructing an atmospheric scene: Based on the atmospheric background model, wind field model and gasglow photochemical radiation model, a comprehensive atmospheric scene is constructed, which includes the three-dimensional wind field spatial distribution and the target gasglow body emissivity spatial distribution. The three-dimensional wind field spatial distribution supports the configuration of multiple preset wind field modes. Among them, the multiple preset wind field modes include a uniform wind field mode, a wind field mode with random disturbances, a wind field mode with horizontal wind shear, and a wind field mode with gravity wave disturbances. (2) Calculate radiative transfer: For the airglow radiation generated by the target airglow layer in the integrated atmospheric scene, the radiative transfer is calculated along the atmospheric path from the target airglow layer to the entrance pupil of the instrument, and the entrance pupil radiation energy distribution is obtained after considering path attenuation and scattering effects. (3) Instrument and platform coupling simulation: Obtain the optical system parameters of the imager, the response characteristic parameters of the detector and the orbital motion parameters of the satellite platform, and couple the entrance pupil radiation energy distribution with the optical transmission characteristics of the imager, the photoelectric conversion characteristics of the detector and the line of sight geometry caused by the satellite motion to generate a simulated interference image; (4) Inversion calculation and error analysis: Inversion calculation is performed on the simulated interferometric image to obtain the inverted horizontal two-dimensional wind field; including circumferential partitioning of the simulated interferometric image, extraction of radial peak position of the interferometric ring, geometric correction of satellite velocity, pairing vector synthesis of line-of-sight wind speed in the overlapping area of ​​multiple exposures, and gridded wind field reconstruction of the target airglow layer; the inverted horizontal two-dimensional wind field is compared point by point with the preset real wind field in the constructed comprehensive atmospheric scene in the same spatial coordinate system, and the deviation distribution and error statistics of wind speed components, wind direction angle and total wind speed are statistically analyzed, and the error evaluation results are output; (5) Parameter sensitivity analysis and optimization adjustment: Based on the output error evaluation results, the optical system parameter configuration of the imager, the single exposure time control strategy and the satellite orbit observation scheme are analyzed for sensitivity, and the imager parameters and observation scheme are optimized and adjusted based on the analysis results.

7. The end-to-end simulation method for a spaceborne near-space horizontal two-dimensional wind field interferometric imager according to claim 6, characterized in that, In step (3), when generating the simulated interferometric image, a noise model related to the detector's operating state is introduced; The noise model includes dark current noise and readout noise.

8. The end-to-end simulation method for a spaceborne near-space horizontal two-dimensional wind field interferometric imager according to claim 6, characterized in that, Step (4) Inversion calculation is as follows: Divide the simulated interferometric image into multiple fan-shaped analysis regions along the circumference, and perform ring integration on the interferometric rings in each fan-shaped region to obtain the radial signal distribution curve; use an asymmetric linear function to numerically fit each radial signal distribution curve, and determine the radial peak position coordinates of the interferometric rings with sub-pixel accuracy; correct the radial component of the satellite motion for the peak position offset in each line of sight direction according to the real-time position and velocity vector of the satellite orbit; identify the spatial overlap position of the ring field of view generated by multiple exposures on the ground, extract two radial wind speed observations from different exposure times and different azimuth angles of the same overlap position, and perform vector synthesis; establish a regular spatial grid of the target airglow layer according to the minimum spatial resolution of the imager, allocate the wind vectors obtained from the overlap position to the corresponding grid cells according to spatial assignment, and average multiple wind vectors in the same grid cell to generate a gridded inverted wind field.

Images