Near space atmosphere profile construction method and device for optical load radiometric calibration

Abstract

The invention provides a near space atmosphere profile construction method and device for optical load radiometric calibration, and belongs to the technical field of remote sensing, and the method comprises the steps: constructing reference atmosphere profiles of different height layers based on at least one atmosphere reanalysis data and radiosonde data; constructing an atmospheric profile structure optimization model based on the hierarchical structure data of the reference atmospheric profile and an entrance pupil radiance observation value obtained through observation; and carrying out iterative solution on the atmospheric profile structure optimization model, and taking the optimal solution of the atmospheric profile structure optimization model as the optimal layered structure of the atmospheric profile. By constructing reference atmosphere profiles and atmosphere profile structure optimization models of different height layers, local high-resolution atmosphere characteristics of different height layers can be conveniently determined, the precision of radiation transfer calculation is improved, and the reliability of a radiation calibration result is remarkably improved.

Description

Technical Field

[0001] The present invention relates to the field of remote sensing technology, and in particular to a method and device for constructing a near-space atmospheric profile using optical payload radiation calibration. Background Art

[0002] In the field of remote sensing, radiometric calibration of optical payloads is a critical step in ensuring the accuracy and consistency of remote sensing data. Its precision directly impacts the reliability of applications in a variety of fields, including surface feature inversion, climate change monitoring, and environmental assessment. The core goal of radiometric calibration is to convert the digital signals (DN values) received by remote sensing payloads into physical quantities such as radiance values, enabling remote sensing images to reflect the true radiometric characteristics of the target surface. This ensures comparability and consistency of data across time, space, and multiple payloads, providing a reliable data foundation for subsequent remote sensing data analysis and scientific research. However, the lack of high-precision radiometric calibration significantly increases the uncertainty and error of optical remote sensing data in surface feature classification, change detection, and parameter inversion, seriously impacting the accuracy of applications and the scientific nature of decision-making.

[0003] In spaceborne remote sensing, there is an atmosphere between the satellite payload and the ground target. The radiation energy of the surface target must pass through the atmosphere to reach the payload. The scattering, absorption and re-radiation of the radiation signal by the atmosphere will produce a complex modulation effect on the energy transfer process. The characteristics of the atmospheric state and its vertical distribution characteristics are important factors affecting the radiation transfer process. They show significant differences in different geographical regions and seasons, especially in local environments with complex meteorological conditions. The atmospheric profile describes the changes in atmospheric parameters along the vertical direction and plays a core role in the radiation transfer model. In order to accurately simulate the atmospheric radiation transfer process, it is necessary to obtain high-precision atmospheric temperature, humidity and pressure profiles, accurately calculate the contribution of atmospheric radiation transfer, provide the necessary reference basis for atmospheric correction and radiation calibration, and provide reliable guarantees for the efficient application of remote sensing data.

[0004] At present, the atmospheric radiation transfer simulation calculation in the process of spaceborne optical remote sensing radiation calibration widely adopts the standard atmosphere model that comes with the atmospheric radiation transfer model. However, the standard atmosphere model is constructed based on the statistics of long-term ground-based observation data in the global region. In the radiation transfer simulation process supporting the radiation calibration of optical remote sensing payloads, it has insufficient applicability and a simple layered structure. It shows great limitations when facing complex local environments. It is difficult to describe the atmospheric state and layered structure covering the entire atmospheric height of near-space in the local environment, which in turn affects the radiation calibration accuracy of optical remote sensing and the application value of remote sensing data. Summary of the Invention

[0005] The present invention provides a method and device for constructing a near-space atmospheric profile for optical payload radiation calibration, which solves the defect in the prior art that the atmospheric profile in a local environment cannot meet the radiation calibration accuracy requirements.

[0006] The present invention provides a method for constructing a near-space atmospheric profile using optical payload radiation calibration, comprising: Construct reference atmospheric profiles at different altitudes based on at least one atmospheric reanalysis data set and radiosonde data; Based on the hierarchical structure data of the reference atmospheric profile and the observed entrance pupil radiance observation value, an atmospheric profile structure optimization model is constructed; The atmospheric profile structure optimization model is iteratively solved, and the optimal solution of the atmospheric profile structure optimization model is used as the optimal hierarchical structure of the atmospheric profile.

[0007] As an embodiment, the constructing of an atmospheric profile structure optimization model based on the hierarchical structure data of the reference atmospheric profile and the observed entrance pupil radiance observation value includes: Obtaining, according to the hierarchical structure data of the reference atmospheric profile, an entrance pupil radiance simulation value determined based on an atmospheric radiation transfer model; A cost function is constructed between the entrance pupil radiance simulation value and the entrance pupil radiance observation value to obtain the atmospheric profile structure optimization model.

[0008] As an embodiment, obtaining, based on the hierarchical structure data of the reference atmospheric profile, an entrance pupil radiance simulation value determined based on an atmospheric radiation transfer model includes: Sampling the hierarchical structure data of the reference atmospheric profile to obtain atmospheric profile parameters; Obtain observation geometry data, water vapor parameters, aerosol parameters and surface reflectance spectrum parameters; Determining the ultra-high spectral radiance at the entrance pupil of the satellite payload simulated by the atmospheric radiation transfer model according to the atmospheric profile parameters, the observation geometry data, the water vapor parameters, the aerosol parameters, and the surface reflectance spectrum parameters; A convolution calculation is performed on the ultra-high spectral radiance and the spectral response function of the spaceborne hyperspectral remote sensor to determine the entrance pupil radiance simulation value.

[0009] As an embodiment, constructing a cost function between the entrance pupil radiance simulation value and the entrance pupil radiance observation value includes: Calculate the difference between the simulated value of the entrance pupil radiance and the observed value of the entrance pupil radiance in any wavelength band of the satellite payload; According to the difference and the weight function of any band of the satellite-borne payload, a cost function between the entrance pupil radiance simulation value and the entrance pupil radiance observation value is constructed to obtain the atmospheric profile structure optimization model.

[0010] As an embodiment, it also includes: If the optimal solution of the atmospheric profile structure optimization model is not obtained, the atmospheric profile structure optimization model is adjusted based on a sensitivity analysis method and a standard atmospheric profile until the optimal solution of the atmospheric profile structure optimization model is obtained.

[0011] As an embodiment, the adjusting the atmospheric profile structure optimization model based on the sensitivity analysis method and the standard atmospheric profile includes: Applying disturbance to the standard atmospheric profile based on the sensitivity analysis method to determine the sensitivity coefficient of any band of the satellite-borne payload; Based on the ratio of the sensitivity coefficient of any band of the satellite payload to the sum of the sensitivity coefficients, the weight function of any band of the satellite payload is determined to adjust the atmospheric profile structure optimization model.

[0012] As an embodiment, constructing reference atmospheric profiles at different altitudes based on at least one atmospheric reanalysis data and radiosonde data includes: Determining observation field data and an observation field error covariance matrix at different altitudes based on the radiosonde data; Determining background field data and background field error covariance matrices at different altitudes based on the atmospheric reanalysis data; Constructing a gain matrix for the corresponding altitude layer according to the observation field error covariance matrix and the background field error covariance matrix of each altitude layer; The reference atmospheric profile of the corresponding altitude layer is constructed based on the observation field data, the background field data and the gain matrix of each altitude layer.

[0013] The present invention also provides a near-space atmospheric profile construction device for optical payload radiation calibration, comprising: A first construction module is configured to construct reference atmospheric profiles at different altitude layers based on at least one atmospheric reanalysis data and radiosonde data; A second construction module is configured to construct an atmospheric profile structure optimization model based on the hierarchical structure data of the reference atmospheric profile and the observed entrance pupil radiance observation value; The determination module is used to iteratively solve the atmospheric profile structure optimization model and use the optimal solution of the atmospheric profile structure optimization model as the optimal hierarchical structure of the atmospheric profile.

[0014] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the method for constructing a near-space atmospheric profile for optical payload radiation calibration as described above is implemented.

[0015] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the method for constructing a near-space atmospheric profile for optical payload radiation calibration as described in any one of the above is implemented.

[0016] The method and device for constructing a near-space atmospheric profile for optical payload radiation calibration provided by the present invention facilitate the determination of local high-resolution atmospheric characteristics at different altitude layers by constructing reference atmospheric profiles and atmospheric profile structure optimization models, thereby improving the accuracy of radiation transfer calculations and significantly enhancing the reliability of radiation calibration results. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 This is one of the flow charts of the method for constructing a near-space atmospheric profile for optical payload radiation calibration provided by the present invention.

[0019] Figure 2 This is the second flow chart of the method for constructing a near-space atmospheric profile for optical payload radiation calibration provided by the present invention.

[0020] Figure 3 It is a structural schematic diagram of the near-space atmospheric profile construction device for optical payload radiation calibration provided by the present invention.

[0021] Figure 4 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0022] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0023] The standard atmospheric model of atmospheric radiation transfer model is widely used in the existing atmospheric radiation transfer simulation calculation in the process of satellite-borne optical remote sensing radiation calibration, which has the following defects: First, the standard atmospheric model based on ground-based observation data statistics mainly relies on the typical atmospheric state classification, which can only characterize the atmospheric characteristics at a large regional scale. It has a certain universality at a large regional scale, but cannot accurately characterize the atmospheric state characteristics in a local environment, and it is difficult to meet the high-precision requirements of radiation calibration in a local environment; secondly, the ground-based observation data has the characteristics of single-point independent sampling, does not have good spatial representativeness, and cannot characterize the spatial distribution of the atmosphere; in addition, the vertical stratification height of the ground-based observation data is mostly within 1 km, which cannot cover the vertical height of the near space, making it impossible for the ground-based observation data to well characterize the vertical distribution of the atmosphere within the entire atmospheric layer height of the near space. This will affect the accuracy of radiation transfer simulation in the process of optical payload radiation calibration based on near-space; secondly, the layered structure of the standard atmospheric model is relatively simple, with a stable distribution structure in the vertical direction. However, the actual local atmospheric environment is affected by multiple factors such as geographical conditions and seasonal changes, and the layered structure of the atmosphere is significantly different from that of the standard atmospheric model, resulting in obvious deviations in the results of optical payload radiation calibration, which in turn affects the accuracy of radiation calibration and the reliability of remote sensing data; finally, the existing standard atmospheric models usually adopt fixed layering or preset layering standards, and fail to flexibly adjust the layering structure according to actual local atmospheric conditions. The atmospheric structure at different atmospheric layer heights has different effects on the radiation transfer process. When the layer changes at key atmospheric layer heights (especially the boundary layer and troposphere) are ignored, the layered structure of the atmospheric profile will be unreasonable, thereby reducing the accuracy of optical payload radiation calibration.

[0024] To overcome the current limitations of the standard atmospheric model used in atmospheric radiation transmission simulation calculations during optical remote sensing payload radiation calibration, such as its insufficient applicability and simple layered structure, which makes it difficult to describe the atmospheric state and layered structure covering the entire atmospheric layer in the near-space environment, thus affecting the accuracy of optical remote sensing in radiation calibration and the application value of remote sensing data, the present invention proposes a near-space atmospheric profile construction method for optical payload radiation calibration, aiming to accurately characterize the local atmospheric state characteristics and vertical layered structure used for atmospheric radiation transmission simulation during optical payload radiation calibration based on near-space.

[0025] Figure 1 This is one of the flow charts of the method for constructing near-space atmospheric profiles for optical payload radiation calibration provided by the present invention. Figure 1 As shown, the present invention provides a method for constructing a near-space atmospheric profile for optical payload radiation calibration, which is used for optical payload radiation calibration or atmospheric correction. The method includes the following steps.

[0026] Step S100: constructing reference atmospheric profiles at different altitude layers based on at least one atmospheric reanalysis data and radiosonde data.

[0027] Atmospheric reanalysis data combines historical observational data with numerical models to generate high-temporal and spatial resolution, physically consistent atmospheric datasets. These datasets can recreate historical weather and climate conditions, serving as a foundation for studying climate change and analyzing extreme events. They are widely used in fields such as meteorology, hydrology, and ecology. This paper does not limit the types of atmospheric reanalysis data; it uses ERA5 and MERRA-3 as examples. ERA5 is the fifth-generation global climate reanalysis product provided by the European Centre for Medium-Range Weather Forecasts (ECMWF). It covers a 31km grid and uses 137 levels of resolution from the surface to an altitude of 80km. These data include parameters such as relative humidity, boundary layer height, temperature, wind direction, and surface pressure. MERRA-3 (Modern-Era Retrospective Analysis for Research and Applications, Version 3) is a global atmospheric reanalysis dataset developed by NASA's Goddard Space Flight Center. It provides global meteorological data from 1980 to the present, including temperature, humidity, wind speed, radiation, precipitation, and other meteorological parameters.

[0028] Radiosonde data consist of meteorological data obtained using radiosondes, which are instruments attached to weather balloons that measure and record meteorological parameters at different altitudes in the atmosphere as the balloon ascends.

[0029] Atmospheric reanalysis data include atmospheric profile data at different altitudes. The atmospheric profile data at different altitudes are corrected by using the background field errors of the atmospheric reanalysis data and the observation field errors of the radiosonde data to obtain reference atmospheric profiles at different altitudes, which makes the atmospheric profiles have higher spatial resolution and more accurate physical representation.

[0030] Step S200 : constructing an atmospheric profile structure optimization model based on the hierarchical structure data of the reference atmospheric profile and the observed entrance pupil radiance observation value.

[0031] The hierarchical structure data of the atmospheric profile mainly include the physical properties of the atmosphere at different altitudes, such as temperature, humidity, air pressure and gas composition. The entrance pupil radiance refers to the brightness reflected or radiated from the earth's surface to the direction of the spacecraft's payload and detector. It is usually expressed in L and its unit is (Watts per square meter per steradian). The observed entrance pupil radiance value refers to the observation value of the onboard payload entrance pupil radiance. Onboard payload refers to the various instruments and equipment carried on spacecraft (such as satellites) to achieve their specific scientific, technological, or application missions, including cameras, sensors, radars, communications equipment, scientific instruments, etc.

[0032] The hierarchical structure data of the reference atmospheric profile is used to determine the entrance pupil radiance value simulated by the atmospheric radiative transfer model (ART), i.e., the simulated entrance pupil radiance value. The atmospheric profile structure optimization model is a cost function between the simulated entrance pupil radiance value and the observed entrance pupil radiance value. The ART is a physical model used to describe and calculate the absorption and scattering of radiation signals as they propagate through the atmosphere.

[0033] Step S300 : Iteratively solving the atmospheric profile structure optimization model, and taking the optimal solution of the atmospheric profile structure optimization model as the optimal hierarchical structure of the atmospheric profile.

[0034] The atmospheric profile structure optimization model is iteratively solved so that the error between the entrance pupil radiance simulation value and the entrance pupil radiance observation value reaches a minimum value or converges to a certain value, thereby obtaining the optimal solution of the atmospheric profile structure optimization model.

[0035] It can be understood that the present invention facilitates the determination of local high-resolution atmospheric characteristics at different altitudes by constructing reference atmospheric profiles and atmospheric profile structure optimization models at different altitudes, improves the accuracy of radiation transfer calculations, and significantly enhances the reliability of radiation calibration results.

[0036] Based on the above embodiment, as an optional embodiment, the construction of reference atmospheric profiles of different altitude layers based on at least one atmospheric reanalysis data and radiosonde data includes steps S110 to S140.

[0037] Step S110 : determining observation field data of different altitude layers and an observation field error covariance matrix based on the radiosonde data.

[0038] Step S120: determining background field data and background field error covariance matrix at different altitudes based on the atmospheric reanalysis data.

[0039] Step S130 : constructing a gain matrix corresponding to each altitude layer according to the observation field error covariance matrix and the background field error covariance matrix of each altitude layer.

[0040] Step S140: constructing the reference atmospheric profile of the corresponding altitude layer according to the observation field data, the background field data and the gain matrix of each altitude layer.

[0041] In step S110, the unified calculation formula of the observation field error covariance matrix is ​​as follows: (1) in, represents the observation error covariance matrix, d Represents the distance between any two points; L Indicates the relevant scale length, usually set to 100km; represents the standard deviation of the observation field error, calculated from radiosonde data.

[0042] In step S120, the unified calculation formula of the background field error covariance matrix is ​​as follows: (2) in, represents the background field error covariance matrix, Represents the standard deviation of the background field error, calculated from atmospheric reanalysis data.

[0043] In step S130, the unified calculation formula of the gain matrix is ​​as follows: (3) in, Represents the gain matrix, which indicates the correction amplitude of the background field data; Represents the observation operator matrix, which is used to map the background field data to the observation space. The identity matrix is ​​usually selected.

[0044] In step S140, the unified calculation formula of the reference atmospheric profile is as follows: (4) in, represents the corrected atmospheric profile, i.e. the reference atmospheric profile; Represents background field data, i.e., reanalysis data with large errors; Represents observation field data, that is, reanalysis data with smaller errors.

[0045] Substitute the observation field data and observation field error covariance matrix of different altitude layers, the background field data and background field error covariance matrix of different altitude layers into formula (1) and (2) respectively, and then substitute formula (1) and (2) into formula (3) and (4), and the optimal interpolation results of the reference atmospheric profiles with high precision and high vertical resolution at different altitude layers can be obtained.

[0046] It can be understood that the present invention uses different reanalysis data and ground-based radiosonde data to evaluate the background error values ​​of different reanalysis data at different altitude layers, constructs a covariance matrix of the background error, and through the advantages of the hierarchical structure of different reanalysis data and the accuracy advantages of reanalysis data in different altitude regions, adopts the optimal interpolation method to achieve dynamic adjustment and error minimization at different altitude levels, corrects and integrates the atmospheric profile of the reanalysis data, so that the atmospheric profile has higher spatial resolution and more accurate physical representation.

[0047] On the basis of the above embodiment, as an optional embodiment, the atmospheric profile structure optimization model is constructed based on the hierarchical structure data of the reference atmospheric profile and the observed entrance pupil radiance observation value, including steps S210 to S220.

[0048] Step S210 , obtaining an entrance pupil radiance simulation value determined based on an atmospheric radiation transfer model according to the hierarchical structure data of the reference atmospheric profile.

[0049] Optionally, obtaining the entrance pupil radiance simulation value determined based on the atmospheric radiation transfer model according to the hierarchical structure data of the reference atmospheric profile includes steps S211 to S214.

[0050] Step S211 : sampling the hierarchical structure data of the reference atmospheric profile to obtain atmospheric profile parameters.

[0051] The high-resolution vertical atmospheric profile is obtained from formula (4) as a reference. Different atmospheric profiles (different structures, i.e. atmospheric profiles of different layers) are obtained by continuously adjusting the reference atmospheric profile. ,Right now It also represents the hierarchical structure of the atmospheric profile). The expressions of the atmospheric profile parameters are as follows: (5) in, Indicates Atmospheric profile parameters obtained under atmospheric profile layering parameters; Expressed as atmospheric profile layer parameters, Indicates height, Indicates the number of atmospheric profile layers, for the reference atmospheric profile Sampling to obtain The atmospheric profile of the layer, Represented as the height of each layer. Given the initial , for the reference atmospheric profile Sampling can obtain the initial atmospheric profile parameters .

[0052] Step S212: Obtain observation geometry data, water vapor parameters, aerosol parameters, and surface reflectance spectrum parameters.

[0053] Observation geometry data includes the cosine of the observation zenith angle in the observation geometry. Water vapor parameters include the atmospheric transmittance between the sensor and the sun. The sensor refers to the Earth observation payload / camera carried by a nearby space platform or satellite platform. Aerosol parameters include the atmospheric hemispherical albedo.

[0054] Step S213 , determining the ultra-high spectral radiance at the entrance pupil of the satellite payload simulated by the atmospheric radiation transfer model according to the atmospheric profile parameters, the observation geometry data, the water vapor parameters, the aerosol parameters, and the surface reflectance spectral parameters.

[0055] The atmospheric profile parameters, the observation geometry data, the water vapor parameters, the aerosol parameters, and the surface reflectance spectrum parameters are input into MODTRAN software. MODTRAN (MODerate Resolution atmospheric TRANsmission) is a widely used meteorological and atmospheric radiation transfer model used to predict the transmission characteristics of optical radiation in the atmosphere.

[0056] The calculation formula of ultra-high spectral radiance is as follows: (6) in, represents ultra-high spectral radiance; It represents path radiation, i.e., process radiation; represents the total downward radiation from the sun; Indicates the atmospheric transmittance between the sensor and the sun; ρ Represents the surface reflectivity parameter; S represents the atmospheric hemispheric albedo; Represents the cosine of the observation zenith angle in the observation geometry. 、 and S They are all related to atmospheric profile parameters.

[0057] Step S214 , performing convolution calculation on the ultra-high spectral radiance and the spectral response function of the spaceborne hyperspectral remote sensor to determine the entrance pupil radiance simulation value.

[0058] A spaceborne hyperspectral remote sensor is a satellite sensor that uses hyperspectral imaging technology and can obtain information about surface objects within a relatively narrow band.

[0059] The calculation formula of the entrance pupil radiance simulation value is as follows: (7) in, is the simulated value of entrance pupil radiance, is the hyperspectral radiance (0.1 cm) at the entrance pupil of the satellite payload simulated using the MODTRAN atmospheric radiation transfer model. -1 ), is the spectral response function of the spaceborne hyperspectral remote sensor, λ1 and λ2 represent the starting wavelength and ending wavelength of the sensor channel spectral response function, respectively.

[0060] Atmospheric parameters, surface reflectance parameters, water vapor parameters, aerosol parameters, and observation geometry parameters are input into the MODTRAN software. The MODTRAN software simulates and obtains high spectral resolution radiance data according to formula (6): According to formula (7), the radiance with high spectral resolution is and the spectral response function (SRF) of each sensor band Perform convolution to obtain the entrance pupil radiance data simulated by each channel of the sensor .

[0061] Step S220 , constructing a cost function between the entrance pupil radiance simulation value and the entrance pupil radiance observation value to obtain the atmospheric profile structure optimization model.

[0062] Optionally, constructing a cost function between the entrance pupil radiance simulation value and the entrance pupil radiance observation value includes steps S221 and S222.

[0063] Step S221 , calculating the difference between the simulated entrance pupil radiance value and the observed entrance pupil radiance value in any wavelength band of the satellite payload.

[0064] Step S222 : constructing a cost function between the entrance pupil radiance simulation value and the entrance pupil radiance observation value according to the difference and the weight function of any band of the satellite-borne payload to obtain the atmospheric profile structure optimization model.

[0065] The expression of the atmospheric profile structure optimization model is as follows: (8) in, is the number of bands of the load; and They are respectively the convolution of the spectral response function of the satellite payload and the Observed and simulated values ​​of entrance pupil radiance of the band; Representative The weight function of the band can be fixed or adjustable; Represents the hierarchical structure parameters of the atmospheric profile.

[0066] The simulated entrance pupil radiance data is calculated based on the adjusted atmospheric profile using MODTRAN software (Formula (6), Formula (7)) , by constantly adjusting , that is, continuously adjusting the layered structure of the atmospheric profile until the simulated entrance pupil radiance and the measured entrance pupil radiance value Minimum, that is, until formula (8) reaches the minimum value The best atmospheric profile layer is obtained. At the same time, the different sensitivities of different bands to atmospheric parameters are considered in formula (8), that is, some bands are sensitive to water vapor or other atmospheric parameters, and the weights are introduced. Characterize the sensitivity of atmospheric parameters in different bands.

[0067] It can be understood that the present invention adopts a hierarchical optimization mechanism to construct an atmospheric profile structure optimization model, accurately characterizes the atmospheric profile structure at different altitudes, enhances the accuracy of radiation transfer calculations, and significantly improves the reliability of radiation calibration results. The present invention has wide applicability and scalability, providing a solid technical foundation for multi-platform and multi-scenario remote sensing applications, and providing reliable data support for the radiation calibration of satellite-borne optical payloads.

[0068] like Figure 2 As shown, based on the above embodiment, as an optional embodiment, the present invention also provides the following steps.

[0069] Step S400 : If the optimal solution of the atmospheric profile structure optimization model is not obtained, the atmospheric profile structure optimization model is adjusted based on a sensitivity analysis method and a standard atmospheric profile until the optimal solution of the atmospheric profile structure optimization model is obtained.

[0070] Optionally, the step of adjusting the atmospheric profile structure optimization model based on a sensitivity analysis method and a standard atmospheric profile includes steps S410 to S420.

[0071] Step S410 : applying disturbance to the standard atmospheric profile based on the sensitivity analysis method to determine the sensitivity coefficient of any band of the satellite-borne payload.

[0072] Step S420 : Based on the ratio of the sensitivity coefficient of any band of the satellite-borne payload to the sum of the sensitivity coefficients, a weight function of any band of the satellite-borne payload is determined to adjust the atmospheric profile structure optimization model.

[0073] In step S410, the temperature, humidity and pressure parameters in the standard atmospheric profile are subjected to ±5% perturbations respectively by using the sensitivity analysis method, and the radiance change is simulated using MODTRAN ( ).

[0074] The unified calculation formula of the sensitivity coefficient is as follows: (9) in, To simulate the radiance change value, is the disturbance amount. By applying disturbance to the standard atmospheric profiles of different bands and substituting it into the above formula, we can get the sensitivity coefficients of different bands.

[0075] The calculation formula of the weight function of any band of the satellite payload is as follows: (10) in, is the weight function of the jth band of the satellite payload, is the sensitivity coefficient of the j-th band of the satellite payload.

[0076] It can be understood that the present invention introduces consistent local disturbances into different height intervals of the standard atmospheric profile, such as applying disturbances of ±5% respectively, uses MODTRAN to simulate and calculate the radiance changes before and after the disturbance, calculates the mean of the radiance changes in each band, clarifies the sensitive height intervals of atmospheric parameters, and performs encryption optimization on the atmospheric profile in the sensitive height intervals. It can adjust the atmospheric profile structure optimization model, and based on the actually acquired satellite payload remote sensing data and the surface reflectivity parameters and observation geometry at the time of transit, uses the Bayesian optimization algorithm to iteratively optimize and solve the structural optimization model. The atmospheric profile stratification in the sensitive height interval is continuously optimized using encryption optimization until the model converges to a stable value. When the model meets the optimal solution, the corresponding result is the optimal atmospheric profile stratification structure.

[0077] In summary, the present invention constructs high-precision atmospheric profile data by fusing multi-source reanalysis data and ground-based radiosonde data. Combined with an atmospheric profile structure optimization model, this method provides a more reliable and accurate atmospheric profile reference for the radiation calibration of spaceborne optical payloads. Compared to traditional standard atmospheric profile models, the proposed near-space atmospheric profile construction method for local optical payload radiation calibration not only takes into account the dynamic changes in the local environment but also achieves higher precision optimization in terms of vertical structure stratification, constructing a high-resolution local atmospheric profile, providing a more accurate and optimized atmospheric profile reference for the radiation calibration of optical payloads.

[0078] The device for constructing a near-space atmospheric profile for optical payload radiation calibration provided by the present invention is described below. The device for constructing a near-space atmospheric profile for optical payload radiation calibration described below and the method for constructing a near-space atmospheric profile for optical payload radiation calibration described above can be referenced to each other.

[0079] Figure 3Schematic diagram of the structure of the near-space atmospheric profile construction device for optical payload radiation calibration provided by the present invention. Figure 3 As shown, the present invention also provides a near-space atmospheric profile construction device for optical payload radiation calibration, including the following modules.

[0080] A first construction module 310 is configured to construct reference atmospheric profiles at different altitude layers based on at least one atmospheric reanalysis data and radiosonde data; A second construction module 320 is configured to construct an atmospheric profile structure optimization model based on the hierarchical structure data of the reference atmospheric profile and the observed entrance pupil radiance observation value; The determination module 330 is configured to iteratively solve the atmospheric profile structure optimization model and use the optimal solution of the atmospheric profile structure optimization model as the optimal hierarchical structure of the atmospheric profile.

[0081] As an embodiment, the first building module 310 is further configured to: Obtaining, according to the hierarchical structure data of the reference atmospheric profile, an entrance pupil radiance simulation value determined based on an atmospheric radiation transfer model; A cost function is constructed between the entrance pupil radiance simulation value and the entrance pupil radiance observation value to obtain the atmospheric profile structure optimization model.

[0082] As an embodiment, the first building module 310 is further configured to: Sampling the hierarchical structure data of the reference atmospheric profile to obtain atmospheric profile parameters; Obtain observation geometry data, water vapor parameters, aerosol parameters and surface reflectance spectrum parameters; Determining the ultra-high spectral radiance at the entrance pupil of the satellite payload simulated by the atmospheric radiation transfer model according to the atmospheric profile parameters, the observation geometry data, the water vapor parameters, the aerosol parameters, and the surface reflectance spectrum parameters; A convolution calculation is performed on the ultra-high spectral radiance and the spectral response function of the spaceborne hyperspectral remote sensor to determine the entrance pupil radiance simulation value.

[0083] As an embodiment, the first building module 310 is further configured to: Calculate the difference between the simulated value of the entrance pupil radiance and the observed value of the entrance pupil radiance in any wavelength band of the satellite payload; According to the difference and the weight function of any band of the satellite-borne payload, a cost function between the entrance pupil radiance simulation value and the entrance pupil radiance observation value is constructed to obtain the atmospheric profile structure optimization model.

[0084] As an embodiment, it also includes: The adjustment module is used to adjust the atmospheric profile structure optimization model based on a sensitivity analysis method and a standard atmospheric profile if the optimal solution of the atmospheric profile structure optimization model is not obtained until the optimal solution of the atmospheric profile structure optimization model is obtained.

[0085] As an embodiment, the adjustment module is further configured to: Applying disturbance to the standard atmospheric profile based on the sensitivity analysis method to determine the sensitivity coefficient of any band of the satellite-borne payload; Based on the ratio of the sensitivity coefficient of any band of the satellite payload to the sum of the sensitivity coefficients, the weight function of any band of the satellite payload is determined to adjust the atmospheric profile structure optimization model.

[0086] As an embodiment, constructing reference atmospheric profiles at different altitudes based on at least one atmospheric reanalysis data and radiosonde data includes: Determining observation field data and an observation field error covariance matrix at different altitudes based on the radiosonde data; Determining background field data and background field error covariance matrices at different altitudes based on the atmospheric reanalysis data; Constructing a gain matrix for the corresponding altitude layer according to the observation field error covariance matrix and the background field error covariance matrix of each altitude layer; The reference atmospheric profile of the corresponding altitude layer is constructed based on the observation field data, the background field data and the gain matrix of each altitude layer.

[0087] The device for constructing a near-space atmospheric profile for optical payload radiation calibration provided by the present invention is used to execute the method for constructing a near-space atmospheric profile for optical payload radiation calibration described in any of the above embodiments, and has technical effects corresponding to the method for constructing a near-space atmospheric profile for optical payload radiation calibration, which will not be described in detail.

[0088] Figure 4 An example of a physical structure diagram of an electronic device is shown below. Figure 4As shown, the electronic device may include: a processor 410, a communications interface 420, a memory 430, and a communications bus 440, wherein the processor 410, the communications interface 420, and the memory 430 communicate with each other via the communications bus 440. The processor 410 may call logic instructions in the memory 430 to execute the near-space atmospheric profile construction method for optical payload radiation calibration, which includes: constructing reference atmospheric profiles for different altitude layers based on at least one atmospheric reanalysis data and radiosonde data; constructing an atmospheric profile structure optimization model based on the hierarchical structure data of the reference atmospheric profile and observed entrance pupil radiance observations; and iteratively solving the atmospheric profile structure optimization model, and using the optimal solution of the atmospheric profile structure optimization model as the optimal hierarchical structure of the atmospheric profile.

[0089] Furthermore, the logic instructions in the aforementioned memory 430 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product, stored in a storage medium, includes instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, a mobile hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0090] On the other hand, the present invention also provides a computer program product, which includes a computer program, and the computer program can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the near-space atmospheric profile construction method for optical payload radiation calibration provided by the above methods, and the method includes: constructing reference atmospheric profiles for different altitude layers based on at least one atmospheric reanalysis data and radiosonde data; constructing an atmospheric profile structure optimization model based on the hierarchical structure data of the reference atmospheric profile and the observed entrance pupil radiance observation value; iteratively solving the atmospheric profile structure optimization model, and taking the optimal solution of the atmospheric profile structure optimization model as the optimal hierarchical structure of the atmospheric profile.

[0091] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, it is implemented to execute the near-space atmospheric profile construction method for the optical payload radiation calibration provided by the above-mentioned methods. The method includes: constructing reference atmospheric profiles for different altitude layers based on at least one atmospheric reanalysis data and radiosonde data; constructing an atmospheric profile structure optimization model based on the hierarchical structure data of the reference atmospheric profile and the observed entrance pupil radiance observation value; iteratively solving the atmospheric profile structure optimization model, and taking the optimal solution of the atmospheric profile structure optimization model as the optimal hierarchical structure of the atmospheric profile.

[0092] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in one location or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of the present embodiment. Persons of ordinary skill in the art will be able to understand and implement the present invention without inventive effort.

[0093] Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment can be implemented using software plus a necessary general-purpose hardware platform, or of course, hardware. Based on this understanding, the essence of the above technical solution, or the portion that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, or an optical disk, and includes a number of instructions for causing a computer device (such as a personal computer, server, or network device) to execute the methods described in each embodiment or certain portions of the embodiments.

[0094] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for constructing near-space atmospheric profiles using optical payload radiation calibration, characterized in that: include: Construct reference atmospheric profiles at different altitudes based on at least one atmospheric reanalysis data set and radiosonde data; Based on the hierarchical structure data of the reference atmospheric profile and the observed entrance pupil radiance observation value, an atmospheric profile structure optimization model is constructed; The atmospheric profile structure optimization model is iteratively solved, and the optimal solution of the atmospheric profile structure optimization model is used as the optimal hierarchical structure of the atmospheric profile.

2. The method for constructing near-space atmospheric profiles for optical payload radiation calibration according to claim 1, characterized in that: The step of constructing an atmospheric profile structure optimization model based on the hierarchical structure data of the reference atmospheric profile and the observed entrance pupil radiance observation value comprises: Obtaining, according to the hierarchical structure data of the reference atmospheric profile, an entrance pupil radiance simulation value determined based on an atmospheric radiation transfer model; A cost function is constructed between the entrance pupil radiance simulation value and the entrance pupil radiance observation value to obtain the atmospheric profile structure optimization model.

3. The method for constructing near-space atmospheric profiles for optical payload radiation calibration according to claim 2, characterized in that: The step of obtaining, based on the hierarchical structure data of the reference atmospheric profile, an entrance pupil radiance simulation value determined based on an atmospheric radiation transfer model comprises: Sampling the hierarchical structure data of the reference atmospheric profile to obtain atmospheric profile parameters; Obtain observation geometry data, water vapor parameters, aerosol parameters and surface reflectance spectrum parameters; Determining the ultra-high spectral radiance at the entrance pupil of the satellite payload simulated by the atmospheric radiation transfer model according to the atmospheric profile parameters, the observation geometry data, the water vapor parameters, the aerosol parameters, and the surface reflectance spectrum parameters; A convolution calculation is performed on the ultra-high spectral radiance and the spectral response function of the spaceborne hyperspectral remote sensor to determine the entrance pupil radiance simulation value.

4. The method for constructing near-space atmospheric profiles for optical payload radiation calibration according to claim 3, characterized in that: The constructing a cost function between the entrance pupil radiance simulation value and the entrance pupil radiance observation value includes: Calculate the difference between the simulated value of the entrance pupil radiance and the observed value of the entrance pupil radiance in any wavelength band of the satellite payload; According to the difference and the weight function of any band of the satellite-borne payload, a cost function between the entrance pupil radiance simulation value and the entrance pupil radiance observation value is constructed to obtain the atmospheric profile structure optimization model.

5. The method for constructing near-space atmospheric profiles for optical payload radiation calibration according to claim 4, characterized in that: Also includes: If the optimal solution of the atmospheric profile structure optimization model is not obtained, the atmospheric profile structure optimization model is adjusted based on a sensitivity analysis method and a standard atmospheric profile until the optimal solution of the atmospheric profile structure optimization model is obtained.

6. The method for constructing near-space atmospheric profiles for optical payload radiation calibration according to claim 5, characterized in that: The adjusting of the atmospheric profile structure optimization model based on the sensitivity analysis method and the standard atmospheric profile includes: Applying disturbance to the standard atmospheric profile based on the sensitivity analysis method to determine the sensitivity coefficient of any band of the satellite-borne payload; Based on the ratio of the sensitivity coefficient of any band of the satellite payload to the sum of the sensitivity coefficients, the weight function of any band of the satellite payload is determined to adjust the atmospheric profile structure optimization model.

7. The method for constructing near-space atmospheric profiles for optical payload radiation calibration according to claim 1, characterized in that: The step of constructing reference atmospheric profiles at different altitudes based on at least one atmospheric reanalysis data and radiosonde data comprises: Determining observation field data and an observation field error covariance matrix at different altitudes based on the radiosonde data; Determining background field data and background field error covariance matrices at different altitudes based on the atmospheric reanalysis data; Constructing a gain matrix for the corresponding altitude layer according to the observation field error covariance matrix and the background field error covariance matrix of each altitude layer; The reference atmospheric profile of the corresponding altitude layer is constructed based on the observation field data, the background field data and the gain matrix of each altitude layer.

8. A near-space atmospheric profile construction device for optical payload radiation calibration, characterized in that: include: A first construction module is configured to construct reference atmospheric profiles at different altitude layers based on at least one atmospheric reanalysis data and radiosonde data; A second construction module is configured to construct an atmospheric profile structure optimization model based on the hierarchical structure data of the reference atmospheric profile and the observed entrance pupil radiance observation value; The determination module is used to iteratively solve the atmospheric profile structure optimization model and use the optimal solution of the atmospheric profile structure optimization model as the optimal hierarchical structure of the atmospheric profile.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the method for constructing a near-space atmospheric profile for optical payload radiation calibration according to any one of claims 1 to 7 is implemented.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for constructing a near-space atmospheric profile for optical payload radiation calibration according to any one of claims 1 to 7 is implemented.

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