A sky survey atmospheric wind temperature detection system and method for real-time calibration detection

Abstract

The present application provides a survey atmospheric wind temperature detection system and method with real-time calibration detection, the system includes a survey scanning component, a detection-calibration coupling component, a stray light suppression baffle component, an interference core component, a focusing lens optical imaging component and a scientific-grade weak signal array detector-charge coupled device arranged in sequence; wherein the detection-calibration coupling component is used to couple the calibration laser signal with the airglow radiation luminescence signal, which enters the interference core component after passing through the stray light suppression baffle component to realize real-time calibration wind temperature detection; the system also includes a calibration light source component, which is used to create a uniform laser signal calibration system with stable frequency and set aperture. The advantages of the present application are: it realizes the simultaneous implementation of survey atmospheric wind temperature detection and system calibration, improves the detection accuracy and precision; effectively shields and suppresses stray light and surrounding environmental light pollution, improves the system signal-to-noise ratio; reduces the system volume and reduces the system complexity.

Description

Technical Field

[0001] The present application belongs to the field of precision instruments for detecting atmospheric wind temperature using passive optical remote sensing spectral interferometry technology, and specifically relates to a sky survey atmospheric wind temperature detection system and method for real-time calibration detection. Background Art

[0002] Wind field and temperature are basic physical parameters that characterize the changes in the morphology of the middle and upper atmosphere, and are important components of space environmental parameters. Atmospheric wind field and temperature play a core role in the construction of atmospheric dynamics models and the coupling mechanism of atmospheric photochemical processes. In addition, atmospheric wind field and temperature are not only crucial to the energy and momentum transfer and the interaction between the atmospheres, but also play a key role in understanding the occurrence and evolution of physical phenomena in the atmosphere.

[0003] As an important precision instrument in the field of passive optical remote sensing, the sky survey atmospheric wind and temperature detection system detects the weak airglow radiation emission spectrum produced after the energy level transition of atmospheric molecules, and uses the Doppler frequency shift and broadening effect to invert the atmospheric wind speed and temperature. However, the existing sky survey atmospheric wind and temperature detection system has certain limitations in system structure and detection method. The existing technology cannot perform system calibration and data detection simultaneously, that is, it is impossible to achieve real-time calibration of detection data. The traditional detection scheme is to first calibrate the system parameters using a frequency-stabilized helium-neon laser, and then expose the sky airglow radiation to obtain wind temperature detection data. This detection scheme separates system calibration and actual detection. In the data processing process, the system parameters are interpolated in time, and then the interference fringes obtained by sky exposure are fitted to extract the atmospheric wind speed and temperature.

[0004] First, affected by the intensity of airglow radiation, in order to obtain detection data with sufficient signal-to-noise ratio, the Sky Survey Atmospheric Wind and Temperature Detection System requires a sufficiently long exposure integration time for skyglow detection. Secondly, the core component of the Sky Survey Atmospheric Wind and Temperature Detection System, the monochromatic light coherence interferometer cavity, is extremely sensitive to changes in the environment, especially the changes in the system's optical path length to the ambient temperature. Finally, due to the requirements for the detection optical environment, the Sky Survey Atmospheric Wind and Temperature Detection System is usually deployed in harsh environments to detect signals. Although there is an active temperature control system to assist in temperature control, the ambient temperature of its monochromatic light coherence interferometer cavity still undergoes complex changes.

[0005] Taking all the above factors into consideration, in the actual detection process, the change of the system optical path length caused by the ambient temperature during the skyglow detection exposure cannot be fully captured by the laser system calibration twice before and after, and the system parameter error caused by time interpolation during data processing ultimately increases the uncertainty of atmospheric wind speed detection. Therefore, a sky survey atmospheric wind temperature detection system that can perform real-time calibration detection is needed to track system parameter changes and thermal drift in real time during skyglow exposure, reduce system detection uncertainty, and improve system detection accuracy. Summary of the invention

[0006] The purpose of this application is to overcome the defect that the traditional sky survey atmospheric wind temperature detection system is deployed in a harsh detection environment, and the uncertainty of atmospheric wind speed detection is large due to the complex changes in the airglow radiation signal intensity and the thermal drift of the monochromatic light coherent interference cavity ambient temperature.

[0007] In order to achieve the above-mentioned purpose, the present application proposes a sky survey atmospheric wind temperature detection system with real-time calibration detection, the system comprising a sky survey scanning component, a detection-calibration coupling component, a stray light suppression baffle component, an interference core component, a focusing lens optical imaging component and a scientific-grade weak signal array detector-charge coupled device arranged in sequence; wherein,

[0008] The sky survey scanning component is used for sky survey detection, and introduces the weak airglow radiation luminescence in the system field of view at different azimuth angles and zenith angles into the system, and outputs it to the detection-calibration coupling component;

[0009] The detection-calibration coupling component is used to couple the calibration laser signal with the airglow radiation luminescence signal to form a coupled optical signal; the coupled optical signal passes through the stray light suppression baffle component and then enters the interference core component to realize the real-time calibration wind temperature detection of the system;

[0010] The stray light suppression baffle assembly is used to shield and suppress stray light outside the system field of view and polluting light sources around the system deployment environment;

[0011] The interference core component is used to receive the coupled optical signal output by the stray light suppression baffle component, select an airglow radiation source of a specific wavelength or frequency, and only allow the airglow radiation of the required wavelength band to pass through, thereby generating quasi-monochromatic light, and then make the quasi-monochromatic light generate equal-inclination interference to generate circular interference fringes with alternating light and dark.

[0012] The focusing lens optical imaging component is used to focus the interference fringe image and image it onto the target surface of the scientific-grade weak signal array detector-charge coupled device;

[0013] The scientific-grade weak signal array detector-charge coupled device is used to convert the interference fringe light signal into an electrical signal, and at the same time, sample and quantize the continuous analog signal into a digital signal and record and store it;

[0014] The system further comprises:

[0015] A calibration light source component is used to create a uniform laser signal with stable frequency and set aperture to calibrate the calibration system; a system control and data collection and processing terminal is used to control the system to perform unattended detection, store raw detection data, extract wind speed and temperature, and generate and store atmospheric wind and temperature data products.

[0016] As an improvement of the above system, the sky survey scanning assembly includes two reflectors with high reflectivity and a window glass with high transmittance;

[0017] The sky survey scanning assembly also includes a horizontal axis and a vertical axis that are perpendicular to each other and driven by a servo motor; the vertical axis is rotated to adjust the azimuth angle of the pointing direction of the sky survey scanning assembly; the horizontal axis is rotated to adjust the zenith angle of the pointing direction of the sky survey scanning assembly.

[0018] As an improvement of the above system, the detection-calibration coupling component includes an optical beam splitting wedge and a reflector;

[0019] The reflection surface of the optical beam splitting wedge is parallel to the reflection surface of the reflector and forms an angle of 45° with the horizontal direction.

[0020] As an improvement of the above system, the stray light suppression baffle assembly includes a plurality of metal apertures with different apertures;

[0021] Several metal apertures of different apertures have set angles and positions to suppress stray light.

[0022] As an improvement of the above system, the interference core component includes a narrow-band filter module, a monochromatic light coherent interference cavity module and an active temperature control module;

[0023] The narrow-band filter module is composed of non-imaging filter lenses, which allows the airglow radiation of a specific wavelength or frequency to pass through in a transmission manner, while filtering out interfering light source radiation from the sky and radiation spectral lines excited by other atoms or molecules;

[0024] The monochromatic light coherent interference cavity module comprises high-precision polished coated quartz glass, a spacer ring and a mechanical bracket, and is used to make the quasi-monochromatic light signal output by the narrow-band filter module produce equal-inclination interference;

[0025] The narrow-band filter module and the monochromatic light coherent interference cavity module are placed in the same constant temperature chamber, and the temperature in the constant temperature chamber is controlled by the active temperature control module to maintain a temperature control accuracy of ±0.005°C.

[0026] As an improvement of the above system, the focusing lens optical imaging component is a double-cemented achromatic lens.

[0027] As an improvement of the above system, the calibration light source assembly includes a frequency-stabilized laser, an optical shutter, a first scattering plate group, a first lens group, an optical fiber bundle, a neutral density absorptive filter, a second scattering plate group, a second lens group and milky white diffusion glass arranged in sequence; wherein,

[0028] The frequency-stabilized laser is a laser that generates high-stability frequency and continuous laser;

[0029] The optical shutter controls the frequency-stabilized laser to emit a laser beam by rapidly opening and closing;

[0030] The first scattering sheet group is located at the entrance of the optical fiber bundle and before the first lens group, and is used to evenly diffuse the laser beam;

[0031] The first lens group, combined with the first scattering sheet, is used to expand the laser beam to the aperture size of the optical fiber bundle;

[0032] The optical fiber bundle is used to transmit laser light;

[0033] The neutral density absorption filter is located at the exit of the optical fiber bundle and is used to adjust the intensity of the calibration laser beam source. By selecting a filter with a suitable absorption intensity, it is ensured that the intensity of the calibration laser beam source matches the intensity of the received airglow radiation signal.

[0034] The second scattering sheet group is located after the neutral density absorptive filter and is used to diffuse the laser beam uniformly again;

[0035] The second lens group is used to expand and collimate the diffused laser light;

[0036] The milky white diffusion glass is a translucent diffusion material used to create a uniform calibration laser signal.

[0037] The present application also provides a sky survey wind and temperature detection method for real-time calibration detection, which is implemented based on the above system, and the method includes:

[0038] The sky survey scanning component cyclically scans the airglow radiation signal entering the system in the vertical direction at a zenith angle of 0° and in the four sight lines of east, south, west and north at an elevation angle of 45°;

[0039] The calibration light source component creates and emits a frequency-stabilized laser beam to provide a uniform calibration laser signal for the system;

[0040] The detection-calibration coupling component couples the system calibration light source signal and the actual sky glow radiant luminescence signal and then outputs it;

[0041] The stray light suppression baffle assembly limits the field of view of the system, suppresses and shields stray light outside the field of view;

[0042] The interference core component selects the quasi-monochromatic light of specific wavelength to generate iso-inclined interference and maintain a constant temperature environment; the scientific-grade weak signal array detector-charge-coupled device is cooled to -70℃;

[0043] Scientific-grade weak signal array detector-charge coupled device converts interference fringe light signals into electrical signals, and simultaneously samples and quantizes continuous analog signals into digital signals;

[0044] The system control and data collection and processing terminal control system performs unattended detection, stores raw detection data, extracts wind speed and temperature, generates and stores atmospheric wind and temperature data products.

[0045] Compared with the prior art, the advantages of this application are:

[0046] 1. The sky survey atmospheric wind temperature detection system has a detection-calibration coupling component, which realizes the simultaneous detection of atmospheric wind temperature and system calibration. During the sky airglow exposure detection process, real-time calibration tracks the system parameter changes and thermal drift, reduces the system detection uncertainty caused by changes in airglow radiation intensity and harsh environment, and improves detection accuracy and precision.

[0047] 2. The sky survey atmospheric wind and temperature detection system has a multi-aperture combination that meets the system field of view requirements to form a stray light suppression baffle assembly, which effectively shields and suppresses stray light outside the system field of view and the scattering of polluted light sources around the system deployment environment into the monochromatic light coherent interference cavity system, thereby improving the system signal-to-noise ratio

[0048] 3. The sky survey atmospheric wind temperature detection system uses a narrow-band filter module and a monochromatic light coherent interference cavity module to share a set of active temperature control systems and constant temperature chambers, so that one active temperature control system can complete the temperature control of two components that need temperature control, reducing the number of active temperature control systems in the detection system, reducing the complexity of system design, reducing the total system volume, and reducing the cost of the detection system.

[0049] 4. The innovatively designed calibration light source system of the sky survey atmospheric wind and temperature detection system produces a uniform light source. It is small in size and easy to install, replacing the traditional large and expensive integrating sphere, reducing system costs and size. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 The figure shows the system configuration and optical path schematic diagram of the sky survey atmospheric wind and temperature detection system for real-time calibration detection;

[0051] Figure 2 The figure shows the optical configuration diagram of the calibration light source system in the sky survey atmospheric wind and temperature detection system for real-time calibration detection;

[0052] Figure 3 Shown is the raw data interference diagram obtained by the simultaneous frequency-stabilized laser light source calibration and skyglow exposure detection of the sky survey atmospheric wind and temperature detection system with real-time calibration detection.

[0053] Figure ID:

[0054] A: Sky survey scanning component B, detection-calibration coupling component

[0055] B1: Optical beam splitter wedge B2: Reflector

[0056] C: Stray light suppression baffle assembly D: Interference core assembly

[0057] D1: Narrowband filter module D2: Monochromatic light coherence interference cavity module

[0058] D3: Active temperature control module E: Focusing lens optical imaging component

[0059] F: Scientific-grade weak signal array detector-charge coupled device

[0060] G: Calibration light source assembly G1: frequency-stabilized laser

[0061] G2: Optical shutter G3: First diffuser group

[0062] G4: Second scattering plate group G5: Fiber bundle

[0063] G6: Neutral density absorptive filter G7: Second scattering filter group

[0064] G8: Second lens group G9: Milky white diffused glass DETAILED DESCRIPTION

[0065] The technical solution of the present application is described in detail below with reference to the accompanying drawings.

[0066] like Figure 1 As shown, the present application provides a sky survey atmospheric wind temperature detection system with real-time calibration detection, which includes the following components: a sky survey scanning component A, a detection-calibration coupling component B, a stray light suppression baffle component C, an interference core component D including a narrow-band filter module, a monochromatic light coherence interference cavity and an active temperature control module, a focusing lens optical imaging component E, a scientific-grade weak signal array detector-charge-coupled device F and a calibration light source component G, and a system control and data collection and processing terminal H.

[0067] The sky survey scanning assembly A has two degrees of freedom, which is used for sky survey detection, and introduces the weak airglow light in the system field of view at different azimuths and zenith angles into the system. It is usually set to five directions, namely the vertical zenith direction and the four sight lines of east, south, west and north at a certain elevation angle. Through the cyclic reciprocating motion of the sky survey scanning assembly A, continuous detection in five directions is achieved.

[0068] The detection-calibration coupling component B consists of an optical spectroscopic wedge B1, a reflector B2 (which can be a silver-coated reflector) and a metal black box. It is the core component for realizing the simultaneous wind temperature detection and system laser calibration. It is used to couple the laser signal of the calibration light source component G during skyglow exposure into the interference core component for iso-inclined interference, thereby realizing real-time calibration wind temperature detection of the system.

[0069] The stray light suppression baffle assembly C is composed of multiple metal apertures of different aperture sizes. The metal apertures of different aperture sizes are geometrically arranged to limit the size of the system field of view. They are used to shield and suppress stray light outside the system field of view and polluted light sources around the system deployment environment from entering the system, thereby improving the signal-to-noise ratio of the detection system.

[0070] The interference core component D includes three modules, namely the narrowband filter module D1, the monochromatic light coherent interference cavity module D2 and the active temperature control module D3. The narrowband filter module D1 is used to select the airglow radiation source of a specific wavelength or frequency, filter out the interference light source radiation from the sky, filter out the radiation emission spectrum from other atoms or molecules, and only allow the airglow radiation of the required band to pass through to produce quasi-monochromatic light. The monochromatic light coherent interference cavity module D2 is the core component for producing interference fringes. It is designed based on the principle of optical interference and consists of high-precision polished and coated quartz glass, spacer rings and mechanical brackets. It makes the quasi-monochromatic light filtered by the narrowband filter system produce equal-inclination interference, and coherently superimposes or cancels according to its phase change to produce light and dark circular interference fringes. It achieves the purpose of measuring the Doppler frequency shift and broadening of the target source of airglow radiation and obtaining the neutral atmospheric wind temperature. The active temperature control module D3 is mainly composed of high-precision temperature sensors, temperature signal acquisition and conditioning units, data acquisition cards, heating signal conversion and processing units, heating execution units, insulation materials, and data processing and control terminals including PID controllers, and is a prior art. The constant temperature room made of insulation materials is used to place the monochromatic light coherent interference cavity module D2 and the narrow-band filter module D1. The temperature of the constant temperature room is detected in real time by a high-precision temperature sensor, and the PID controller in the data processing and control terminal accurately controls the operation of the heating execution unit to ensure that the monochromatic light coherent interference cavity module D2 and the narrow-band filter module D1 in the constant temperature room are in a constant temperature environment with a temperature control accuracy of ±0.005°C, and the constant temperature is higher than the room temperature.

[0071] The focusing lens optical imaging component E is a double-cemented achromatic lens, which is used to focus the interference fringe image transmitted by the monochromatic light coherent interference cavity module D2 and image it onto the target surface of the back-end scientific-grade weak signal array detector-charge coupled device F, which can significantly reduce imaging chromatic aberration and spherical aberration and improve imaging quality.

[0072] The scientific-grade weak signal array detector - Charge Coupled Device F is a 1024×1024 pixel two-dimensional array, each pixel is 13 microns in size, and can be cooled to -70°C by semiconductor refrigeration for stable operation. It is used to convert the light and dark interference fringe light signals into electrical signals, and at the same time, it samples and quantizes the continuous analog signals into digital signals for recording and storage, and has the advantages of low dark current and high photoelectric conversion efficiency.

[0073] like Figure 2 As shown, the calibration light source assembly G is composed of a frequency-stabilized laser G1 (e.g., a frequency-stable helium-neon laser), an optical shutter G2, a first scattering plate group G3, a second scattering plate group G7, a first lens group G4, a second lens group G8, an optical fiber bundle G5, a neutral density absorptive filter G6, and an opalescent diffusion glass G9. The assembly is used to provide and create a frequency-stable, uniform calibration light source with a set aperture, to calibrate and track system parameter changes in real time during sky survey wind and temperature detection, monitor system thermal drift, improve the accuracy of wind and temperature detection, and reduce detection uncertainty.

[0074] The system control and data collection and processing terminal H is used to control the unattended detection of the entire system, detect data storage and extraction, and store wind temperature data. Specifically, it includes first controlling the sky scanning component A to cyclically scan the vertical zenith direction and the four sight lines of east, south, west and north at a certain elevation angle, and receiving the airglow radiation signal into the system; secondly, obtaining the constant temperature of the active temperature control module D3, and controlling the heating execution unit in real time and accurately through the PID controller to ensure that the constant temperature chamber is in a constant temperature environment; then controlling the scientific-grade weak signal array detector-charge-coupled device F to cool down to -70℃ to reduce the detector working thermal noise, control the detector shutter and collect and store the original interference fringe data; finally, controlling the optical shutter G2 in the calibration light source component G to decide whether to emit a frequency-stabilized helium-neon laser to provide a uniform calibration light source for the system. In addition, the original interference fringe image data is detected through the terminal storage, and the atmospheric wind temperature data products are analyzed, extracted and stored from the interference fringe data.

[0075] Example 1

[0076] like Figure 1As shown, a sky survey atmospheric wind temperature detection system with real-time calibration detection can synchronize system calibration during the sky survey wind temperature detection process, track system parameter changes, realize real-time calibration wind temperature detection, reduce the detection uncertainty caused by thermal drift of the system due to environmental changes, and improve the wind temperature detection accuracy; specifically, it includes the following components: a sky survey scanning component A, a detection-calibration coupling component B, a stray light suppression baffle component C, an interference core component D including a narrow-band filter module D1, a monochromatic light coherent interference cavity module D2 and an active temperature control module D3, a focusing lens optical imaging component E, a scientific-grade weak signal array detector-charge coupled device F and a calibration light source component G, and a system control and data collection and processing terminal H.

[0077] The following is a detailed description of each component:

[0078] The sky survey scanning assembly A is a precision mirror system composed of two high-reflectivity mirrors and a high-transmittance window glass. The assembly achieves precise pointing to any point in the sky through two mutually perpendicular rotation axes. The rotation of the vertical axis is responsible for changing the azimuth of the pointing direction, while the rotation of the horizontal axis adjusts the zenith angle of the pointing direction. The two axes are driven by servo motors and can achieve 360° continuous rotation, ensuring that the weak airglow within the system field of view at any point in the sky can be effectively introduced. In the sky survey atmospheric wind temperature detection system, it is usually set to run in five directions. This includes the vertical direction with a zenith angle of 0°, and the four line of sight directions of east, south, west and north with a zenith angle of 45°. By precisely controlling the cyclic reciprocating motion of the sky survey scanning assembly A, the assembly can achieve continuous and efficient detection of wind temperature in five directions.

[0079] The detection-calibration coupling assembly B is composed of carefully designed optical components, including an optical spectroscopic wedge B1, a reflector B2, and a metal bracket and box for fixing these components. The reflection surface of the optical spectroscopic wedge B1 is precisely parallel to the reflection surface of the reflector B2, and forms an angle of 45° with the horizontal direction to optimize the directionality of the optical path. In order to avoid internal interference during the transmission process, the two surfaces of the optical spectroscopic wedge B1 are designed to have a wedge structure with a certain angle, and the angle is carefully designed to be 4° to meet the requirements of size and performance. In the actual detection process, considering that the intensity of the airglow radiation luminescence signal is much lower than the intensity of the laser calibration light source, the reflectivity of the optical spectroscopic wedge B1 is designed to be 95% to ensure the reflection of the airglow radiation luminescence signal emitted vertically downward by the sky survey scanning assembly; at the same time, the transmittance is 5%, allowing the horizontally incident laser calibration light source signal to be transmitted smoothly.

[0080] Reflector B2 uses its high reflectivity to effectively reduce the signal loss after the laser calibration light source is coupled with the airglow radiation light source. The metal fixing bracket and box are not only used to accurately install and fix these key optical components, but also ensure the transmission efficiency and accuracy of the optical signal, while avoiding interference from external light sources. This component is the core of achieving simultaneous airglow detection and laser calibration. During the skyglow exposure detection, it couples the laser signal of the calibration light source component G into the interference system to generate interference fringes, providing key technical support for the system's real-time calibration detection of atmospheric wind temperature.

[0081] The stray light suppression baffle assembly C is a precision device composed of a series of metal apertures with different apertures, with a total length of 250mm. The design of these apertures fully considers the field of view size and detection requirements of the system to achieve optimal light path control. Through precise geometric arrangement, these metal apertures are installed in specific positions and work together to limit the field of view of the system. The installation position and angle of each aperture are precisely calculated and carefully adjusted to ensure the best stray light suppression effect. This component plays a vital role in shielding stray light outside the field of view of the system, and also effectively suppresses scattered contamination light sources from the surrounding observation environment of the system. Improve the signal-to-noise ratio of the detection system, thereby improving the detection accuracy and data quality of the system.

[0082] The interference core component D is a key part of the wind and temperature detection system that uses spectral interference technology to generate interference fringes to detect atmospheric wind speed and temperature. It consists of three modules: narrow-band filter module D1, monochromatic light coherent interference cavity module D2 and active temperature control module D3.

[0083] The narrowband filter module D1 is designed to allow radiation sources of specific wavelengths or frequencies to pass through by transmission, while filtering out interfering light source radiation from the sky and radiation emission spectrum lines stimulated by other atoms or molecules. The central wavelength of this module is 630.0nm, the filter half bandwidth is less than 2nm, and the transmittance is greater than 80%. In order to avoid the influence of self-interference, non-imaging filter lenses are used.

[0084] The monochromatic light coherent interference cavity module D2 is the core of the detection system that converts the frequency domain changes of the airglow Doppler effect into spatial domain changes to detect the atmospheric wind field and temperature. It is designed based on the principle of optical interference, with a central wavelength of 630nm, a surface accuracy of λ / 100, and a reflectivity greater than 70%. The module is composed of high-precision polished and coated quartz glass, spacer rings and mechanical brackets. It can produce equal-inclination interference in the monochromatic light coherent interference cavity, achieve coherent superposition or cancellation through phase changes, and produce interference fringes. The peak center and width of the interference fringes reflect the Doppler frequency shift and broadening of the airglow radiation target source, realizing the measurement of neutral atmospheric wind temperature.

[0085] Since the optical elements of the narrowband filter module D1 and the monochromatic light coherent interference cavity module D2 are extremely sensitive to changes in ambient temperature, in order to reduce the systematic detection deviation and uncertainty caused by thermal effects, an active temperature control module D3 is used to assist in temperature control. The active temperature control module D3 adopts existing technology and is composed of high-precision temperature sensors, temperature signal acquisition and conditioning systems, data acquisition cards, heating signal conversion and processing units and execution units, insulation materials, and data processing and control terminals including PID controllers. The constant temperature chamber is composed of 4 cm thick insulation materials, which are used to build a constant temperature environment and place interference cavities and filter components, and the heating execution unit is accurately controlled by the PID controller. Ensure that the monochromatic light coherent interference cavity module D2 and the narrowband filter module D1 in the constant temperature chamber work in a constant temperature environment with a temperature control accuracy of ±0.005°C. In actual detection, the temperature control target temperature range is generally set to 30-35°C.

[0086] The focusing lens optical imaging component E is a double-glued achromatic lens with a focal length of 300mm. Through this component, the interference fringe image generated by the monochromatic light coherent interference cavity module D2 is precisely focused and clearly imaged onto the target surface of the scientific-grade weak signal array detector-charge coupled device F. The use of a double-glued achromatic lens reduces chromatic aberration and spherical aberration in the imaging process, thereby improving the imaging quality. By carefully adjusting the focal length, the clarity and contrast of the interference fringe image can be ensured, which is crucial for accurate system calibration and data measurement and analysis.

[0087] The scientific-grade weak signal array detector - Charge Coupled Device F, is a high-performance imaging device with an array layout of 1024×1024 pixels, and the size of each pixel is 13um. The photoelectric conversion efficiency of this detector exceeds 90%, and it can be stably operated at -70℃ through semiconductor refrigeration technology, thereby effectively reducing thermal noise during operation. The main function of this detector is to convert the light and dark interference fringe signals imaged by the focusing lens into electrical signals, and at the same time sample and quantize the continuous analog signals into digital signals for recording and storage. Due to its low dark current and high photoelectric conversion efficiency, this detector has significant advantages in capturing weak signals.

[0088] Calibration light source assembly G, whose optical configuration is as follows Figure 2 As shown, the calibration light source assembly G is composed of a frequency-stabilized laser G1, an optical shutter G2, a first scattering plate group G3, a second scattering plate group G7, a first lens group G4, a second lens group G8, an optical fiber bundle G5, a neutral density absorptive filter G6 and a milky white diffusion glass G9.

[0089] The frequency-stabilized laser G1 is a continuous laser with a wavelength of 633nm and a power of 1.2mW. Its frequency stability is extremely high, with a frequency uncertainty of 2MHz within 8 hours, and it can achieve stable frequency locking within 15 minutes. The optical shutter G2 plays a key role in this component. It can be quickly opened and closed through programming control, thereby accurately controlling the emission of the frequency-stabilized laser G1 light source. The first scattering plate group G3 and the second scattering plate group G7 are scattering plates of 600 mesh and 1500 mesh respectively, located at the entrance and exit of the optical fiber, responsible for evenly diffusing the laser light source. The optical fiber bundle G5 is a large-diameter hose optical fiber bundle with a length of 1m and a light-clearing diameter of 6mm. The transmission principle is based on "total reflection of light". The main function is to guide the frequency-stabilized laser G1 light source controlled by the optical shutter G2 into the collimating lens barrel. The first lens group G4 is composed of a lens with a diameter of 10mm and a focal length of 10mm, which is used to expand the laser to the diameter of the optical fiber bundle G5. The second lens group G8 is composed of a lens with a diameter of 75mm and a focal length of 200mm, which is used to expand and collimate the laser to adapt to the subsequent optical system. The neutral density absorption filter G6 is used to adjust the intensity of the calibration light source. By selecting a filter with appropriate absorption intensity, it can be ensured that the intensity of the calibration light source matches the intensity of the received airglow radiation signal to avoid affecting the extraction of wind temperature information in the interference fringes due to excessive signal intensity differences. As a translucent diffusion material, the milky white diffusion glass G9 is used to create uniform calibration light source illumination after the light is emitted from the lens barrel, ensuring the uniformity of the light source when the system is performing wind temperature detection.

[0090] This component is used to provide and create a calibrated uniform light source with stable frequency and a certain caliber, to calibrate and track system parameter changes in real time during sky survey wind and temperature detection, monitor system thermal drift, improve the accuracy of wind and temperature detection, and reduce system detection uncertainty. The light source provided by the calibration light source component G is a frequency-stable laser light source. During the detection of the actual sky airglow radiation signal, the system calibration signal is synchronously detected through the detection-calibration coupling component B. In actual detection, by detecting the changes in the interference fringes generated by the calibration signal, the complex changes in the thermal drift of the system parameters caused by the changes in the environment in which the system is located can be tracked. Therefore, it is possible to track and calibrate to obtain more accurate system parameters, which are used to invert the atmospheric wind speed and temperature from the interference fringes generated by the detected airglow signal, thereby improving the accuracy of the inversion. This system can detect the calibration light source signal while detecting the sky airglow signal, and each forms interference fringes that do not contaminate each other. However, the existing technology cannot detect the airglow signal and the calibration light source signal at the same time. It is necessary to complete the calibration signal detection first, and then perform the airglow radiation luminescence signal detection; therefore, the parameter changes caused by the environmental changes in the system during the airglow exposure detection cannot be tracked and obtained by calibration.

[0091] The system control and data collection and processing terminal H is used to control the unattended detection of the sky survey atmospheric wind temperature detection system, detect data storage and extraction, and store wind temperature data. Specifically, it first controls the sky survey scanning component to cyclically scan the vertical direction of the zenith angle of 0° and the four sight lines of east, south, west, and north at an elevation angle of 45° to enter the system; secondly, the temperature of the constant temperature chamber where the monochromatic light coherent interference cavity module D2 and the narrowband filter module D1 are located is obtained, and the heating execution unit is controlled in real time and accurately through the PID controller to ensure the constant temperature environment of the constant temperature chamber; then the scientific-grade weak signal array detector-charge-coupled device F is controlled to cool down to -70℃ to reduce the working thermal noise of the detector, control the detector shutter, and collect and store the original interference fringe data; finally, it controls whether the optical shutter G2 in the calibration light source component G emits a laser with a stable frequency to provide a uniform calibration light source for the system. In addition, the original interference fringe image data is detected through the terminal storage, and the atmospheric wind temperature data products are analyzed and extracted from the interference fringe data and stored.

[0092] Figure 3 The figure shows the original data of interference fringes actually detected by the sky survey atmospheric wind and temperature detection system with real-time calibration detection. The figure shows two signal fringes of different intensities: the brighter fringes are generated by the calibration light source of the frequency-stabilized laser G1, while the darker fringes are interference fringes formed by the equal-inclination interference of the airglow radiation in the atmosphere in the monochromatic light coherent interference cavity. The system parameter information obtained by calibration from the fringes of the frequency-stabilized laser G1 is applied to the fringes of the airglow radiation signal. Further analysis of the movement of the peak center of the airglow interference fringes and the change in the fringes width can accurately extract the wind speed and temperature data in the atmosphere.

[0093] Example 2

[0094] The present application also provides a method for detecting atmospheric wind and temperature in a sky survey by real-time calibration detection, which is implemented based on the above system and includes:

[0095] The sky survey scanning component cyclically scans the airglow radiation signal entering the system in the vertical direction at a zenith angle of 0° and in the four sight lines of east, south, west and north at an elevation angle of 45°;

[0096] The calibration light source component creates and emits a frequency-stabilized laser beam to provide a uniform calibration laser signal for the system;

[0097] The detection-calibration coupling component couples the system to calibrate the laser signal and the actual skyglow radiation luminescence signal and then outputs it;

[0098] The stray light suppression baffle assembly limits the system field of view, suppresses and shields stray light outside the field of view; the interference core assembly selects quasi-monochromatic light of specific wavelength airglow radiation to produce iso-inclined interference and maintain a constant temperature environment; the scientific-grade weak signal array detector-charge-coupled device is cooled to -70℃;

[0099] Scientific-grade weak signal array detector-charge coupled device converts interference fringe light signals into electrical signals, and simultaneously samples and quantizes continuous analog signals into digital signals;

[0100] The system control and data collection and processing terminal control system performs unattended detection, stores raw detection data, extracts wind speed and temperature, generates and stores atmospheric wind and temperature data products.

[0101] The advantages of this application are:

[0102] 1. Signal detection and system calibration can be performed simultaneously. In the prior art, calibration and detection are separated and cannot be performed synchronously, that is, system calibration is completed first, and then signal detection is performed, and the two are not performed synchronously at the same time. In the present application, by designing a detection-calibration coupling component B, system calibration and signal detection can be performed simultaneously. In other words, the prior art does not have a detection-calibration coupling component, and the real-time calibration and detection function of the present system cannot be realized. Inaccurate system calibration will increase the uncertainty of the final detection; and the optical path coupling design adopted in the present system realizes real-time system parameter tracking, calibration and detection, thereby improving the accuracy of atmospheric wind field and temperature parameter detection.

[0103] 2. This system uses a stray light suppression baffle component C, which can shield and suppress stray light outside the system field of view and polluted light sources around the system deployment environment from entering the system to a certain extent, thereby improving the signal-to-noise ratio of the detection system.

[0104] 3. In this system, the narrowband filter module D1 and the monochromatic light coherent interference cavity module D2 share a set of active temperature control system and constant temperature chamber design, while in the prior art, the two systems require independent constant temperature chambers and temperature control systems. Therefore, compared with the prior art, this system realizes one active temperature control module D3 to complete the temperature control of two components that need temperature control, reduces the number of active temperature control systems in the detection system, reduces the complexity of system design, reduces the total volume of the system, and reduces the cost of the detection system.

[0105] 4. The calibration light source component G of this system is different from the prior art. In the prior art, a large integrating sphere is usually used to create a uniform light source for system calibration. Such a large integrating sphere is difficult to apply to the system where calibration and detection are performed simultaneously, and it is expensive and needs to be customized. The calibration light source component G in this system is realized by a simple combination of optical components, which has the characteristics of small size, low cost and easy implementation.

[0106] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and are not intended to limit the present application. Although the present application is described in detail with reference to the embodiments, a person skilled in the art should understand that any modification or equivalent replacement of the technical solutions of the present application does not depart from the spirit and scope of the technical solutions of the present application and should be included in the scope of the claims of the present application.

Claims

1. A sky survey atmospheric wind and temperature detection system with real-time calibration detection, characterized in that: The system includes a sky survey scanning component, a detection-calibration coupling component, a stray light suppression baffle component, an interference core component, a focusing lens optical imaging component and a scientific-grade weak signal array detector-charge coupled device arranged in sequence; wherein, The sky survey scanning component is used for sky survey detection, and introduces the weak airglow radiation luminescence in the field of view of the system at different azimuth angles and zenith angles into the system, and outputs it to the detection-calibration coupling component; The detection-calibration coupling component is used to couple the calibration laser signal with the airglow radiation luminescence signal to form a coupled optical signal. The coupled optical signal passes through the stray light suppression baffle component and then enters the interference core component to realize the real-time calibration wind temperature detection of the system; The stray light suppression baffle assembly is used to shield and suppress stray light outside the system field of view and polluting light sources around the system deployment environment; The interference core component is used to receive the coupled optical signal output by the stray light suppression baffle component, select the airglow radiation of a specific wavelength or frequency, and only allow the airglow radiation of the required wavelength band to pass through, thereby generating quasi-monochromatic light, and then make the quasi-monochromatic light generate equal-inclination interference to generate circular interference fringes with alternating light and dark. The focusing lens optical imaging component is used to focus the interference fringe image and image it onto the target surface of the scientific-grade weak signal array detector-charge coupled device; The scientific-grade weak signal array detector-charge coupled device is used to convert the interference fringe light signal into an electrical signal, and at the same time, sample and quantize the continuous analog signal into a digital signal and record and store it; The system further comprises: A calibration light source component is used to create a uniform laser signal with stable frequency and set aperture to calibrate the calibration system; a system control and data collection and processing terminal is used to control the system to perform unattended detection, store raw detection data, extract wind speed and temperature, and generate and store atmospheric wind and temperature data products.

2. The sky survey atmospheric wind and temperature detection system with real-time calibration detection according to claim 1 is characterized in that: The sky survey scanning assembly includes two reflectors with high reflectivity and a window glass with high transmittance; The sky survey scanning assembly also includes a horizontal axis and a vertical axis that are perpendicular to each other and driven by a servo motor; the vertical axis is rotated to adjust the azimuth angle of the pointing direction of the sky survey scanning assembly; the horizontal axis is rotated to adjust the zenith angle of the pointing direction of the sky survey scanning assembly.

3. The sky survey atmospheric wind and temperature detection system with real-time calibration detection according to claim 1 is characterized in that: The detection-calibration coupling component includes an optical spectroscopic wedge and a reflector; The reflection surface of the optical beam splitting wedge is parallel to the reflection surface of the reflector and forms an angle of 45° with the horizontal direction.

4. The sky survey atmospheric wind and temperature detection system with real-time calibration detection according to claim 1 is characterized in that: The stray light suppression baffle assembly includes a plurality of metal apertures of different apertures; Several metal apertures of different apertures have set angles and positions to suppress stray light.

5. The sky survey atmospheric wind and temperature detection system with real-time calibration detection according to claim 1 is characterized in that: The interference core component includes a narrow-band filter module, a monochromatic light coherence interference cavity module and an active temperature control module; The narrow-band filter module is composed of non-imaging filter lenses, which allows the airglow radiation of a specific wavelength or frequency to pass through in a transmission manner, while filtering out interfering light source radiation from the sky and radiation spectral lines excited by other atoms or molecules; The monochromatic light coherent interference cavity module comprises high-precision polished coated quartz glass, a spacer ring and a mechanical bracket, and is used to make the quasi-monochromatic light signal output by the narrow-band filter module produce equal-inclination interference; The narrow-band filter module and the monochromatic light coherent interference cavity module are placed in the same constant temperature chamber, and the temperature in the constant temperature chamber is controlled by the active temperature control module to maintain a temperature control accuracy of ±0.005°C.

6. The sky survey atmospheric wind and temperature detection system with real-time calibration detection according to claim 1 is characterized in that: The focusing lens optical imaging component is a double-glued achromatic lens.

7. The sky survey atmospheric wind and temperature detection system with real-time calibration detection according to claim 1 is characterized in that: The calibration light source assembly comprises a frequency-stabilized laser, an optical shutter, a first scattering sheet group, a first lens group, an optical fiber bundle, a neutral density absorptive filter, a second scattering sheet group, a second lens group and milky white diffusion glass arranged in sequence; wherein, The frequency-stabilized laser is a laser that generates high-stability frequency and continuous laser; The optical shutter controls the frequency-stabilized laser to emit a laser beam by rapidly opening and closing; The first scattering sheet group is located at the entrance of the optical fiber bundle and before the first lens group, and is used to evenly diffuse the laser beam; The first lens group, combined with the first scattering sheet group, is used to expand the laser beam to the aperture size of the optical fiber bundle; The optical fiber bundle is used to transmit laser light; The neutral density absorption filter is located at the exit of the optical fiber bundle and is used to adjust the intensity of the calibration laser beam source. By selecting a filter with a suitable absorption intensity, it is ensured that the intensity of the calibration laser beam source matches the intensity of the received airglow radiation signal. The second scattering sheet group is located after the neutral density absorptive filter and is used to diffuse the laser beam uniformly again; The second lens group is used to expand and collimate the diffused laser light; The milky white diffusion glass is a translucent diffusion material used to create a uniform calibration laser signal.

8. A method for detecting atmospheric wind and temperature in a sky survey with real-time calibration detection, implemented based on the system described in any one of claims 1 to 7, the method comprising: The sky survey scanning component cyclically scans the airglow radiation signal entering the system in the vertical direction at a zenith angle of 0° and in the four sight lines of east, south, west and north at an elevation angle of 45°; The calibration light source component creates and emits a frequency-stabilized laser beam to provide a uniform calibration laser signal for the system; The detection-calibration coupling component couples the system to calibrate the laser signal and the actual skyglow radiation luminescence signal and then outputs it; The stray light suppression baffle assembly limits the field of view of the system, suppresses and shields stray light outside the field of view; The interference core component selects the quasi-monochromatic light of specific wavelength to generate iso-inclined interference and maintain a constant temperature environment; the scientific-grade weak signal array detector-charge-coupled device is cooled to -70℃; Scientific-grade weak signal array detector-charge coupled device converts interference fringe light signals into electrical signals, and simultaneously samples and quantizes continuous analog signals into digital signals; The system control and data collection and processing terminal control system performs unattended detection, stores raw detection data, extracts wind speed and temperature, generates and stores atmospheric wind and temperature data products.

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