Geometric observation error quantification method, device and system for earth radiation lunar exploration platform

Abstract

The application discloses a kind of geometric observation error quantification methods, device and system of earth radiation lunar base detection platform, including obtaining the true value of the radiation flux of short wave and long wave from the top layer of earth atmosphere to moon surface;Constantly change the value of observation geometry parameter, based on the true value of radiation flux, and the preset pixel observation simulation value calculation formula, the short wave pixel observation value and long wave pixel observation value corresponding to different observation geometry parameters are calculated, and the pixel observation simulation value calculation formula considers atmospheric parameter, ground cover type and observation geometry parameter;Based on the true value of radiation flux, the short wave pixel observation value and long wave pixel observation value corresponding to different observation geometry parameters, the corresponding pixel observation error and the sensitivity of each pixel observation error to the change of each type of observation geometry parameter are calculated;Based on the square root mean of all sensitivities, time average operation is carried out, and the geometric observation error quantification value is calculated.The present application can make up for the defects of the related research, and provide support for error calibration.

Description

Technical Field

[0001] This invention belongs to the field of scientific design of imaging spectrometers, and specifically relates to a method, device and system for quantifying geometric observation errors of a lunar-based Earth radiation detection platform. Background Technology

[0002] As one of the cutting-edge technologies for future deep space exploration, research on lunar-based Earth radiation observation systems can further improve existing Earth radiation budget monitoring systems. Developing methods for quantifying the geometric observation errors of lunar-based Earth radiation observation platforms is crucial for the platform's system error correction work; however, current research and technologies are still unable to quantitatively describe these geometric observation errors.

[0003] Clarifying the changes in the Earth system's radiation energy balance is essential for deepening humanity's understanding of global climate change. Due to the rapid changes in the Earth's rotation and cloud and atmospheric distribution over time, the shortwave radiation reflected by the Earth system and its own longwave radiation exhibit global, large-scale, instantaneous variations. Traditional ground-based stations, due to their uneven distribution and limited number, cannot meet the needs of global observation of changes in the Earth's reflected shortwave and its own infrared longwave radiation. Satellite observations, on the other hand, can provide global-scale data with a certain temporal resolution for Earth's radiation energy balance research because they can uniformly cover the globe over a certain period. However, artificial Earth satellite measurements still have many shortcomings. The fundamental reason lies in some inherent problems of artificial Earth satellite platforms, such as differences in instrument design and operational calibration methods across different platforms, leading to significant deviations in observed values ​​of the same parameter in the same region. Even with the same instruments mounted on different satellites, data consistency is reduced due to differences in satellite orbits and instrument aging. Although improvements can be made through on-orbit calibration and other techniques, some deviations will still exist. Furthermore, the limited lifespan of artificial satellites restricts the observation period of the onboard platform, hindering the acquisition of long-term, stable, and continuous observational data. Furthermore, existing low-Earth orbit satellite platforms have limited instantaneous fields of view and a limited number of transits. The sampling times for time-averaged data vary across different regions, leading to errors. Additionally, the limited daily sampling frequency results in insufficient temporal resolution to capture smaller-scale radiative transfer processes, such as radiative transfer between clouds and the ground. Therefore, it is essential to find a more stable platform with greater instantaneous coverage and higher temporal resolution to observe changes in Earth's energy balance, addressing the shortcomings of existing spaceborne platforms and exploring the mechanisms and patterns of Earth's radiation balance.

[0004] As Earth's natural satellite, the Moon's near-surface area provides an excellent location for observing Earth's radiation energy. Compared to low-Earth orbit (LEO) spaceborne observation platforms, the Moon-based Earth Radiation Observatory (MERO) offers the following advantages: 1. Due to the Earth-Moon distance being approximately 100 times the Moon's diameter, the geometric characteristics of Earth observations at most locations near the Moon's surface are highly consistent. This reduces data bias between lunar-based observatories at different landing points, facilitating the fusion of multi-period data and producing more long-term, stable, and continuous Earth radiation energy observation data. 2. The lunar-based platform can conduct continuous observations of most areas of Earth for an average of 12 hours per day, effectively improving the temporal resolution of the observation data. This allows for the capture of small-scale radiative transfer processes that are undetectable by existing spaceborne platforms, thereby deepening our understanding of the mechanisms of radiation budget changes at the top of Earth's atmosphere. 3. The relatively stable radiation environment and thin atmosphere of the Moon provide more accurate in-situ calibration for instruments on board.

[0005] Systematic error calibration plays a crucial role in the construction of a lunar-based Earth radiation observation system, and one of the core tasks is the quantification of geometric observation errors. However, although some exploratory work has been conducted on the preliminary concepts and basic parameters of lunar-based Earth radiation observation instruments, existing research and technologies still cannot quantitatively describe these geometric observation errors. Against this technological backdrop, it is essential to study methods for quantifying geometric observation errors in a lunar-based Earth radiation detection system. Summary of the Invention

[0006] To address the aforementioned issues, this invention proposes a method, device, and system for quantifying geometric observation errors of a lunar-based Earth radiation detection platform. This method can fill the gaps in existing related research, provide support for error calibration, and thus contribute to the advancement of research on the mechanism of lunar-based Earth radiation observation and instrument development.

[0007] To achieve the above-mentioned technical objectives and effects, the present invention is implemented through the following technical solution:

[0008] In a first aspect, the present invention provides a method for quantifying the geometric observation error of a lunar-based Earth radiation detection platform, comprising:

[0009] Obtain the true values ​​of shortwave and longwave radiation flux from the top of Earth's atmosphere to the lunar surface;

[0010] By continuously changing the values ​​of the observation geometric parameters, based on the true values ​​of the shortwave and longwave radiative flux and the preset pixel observation simulation value calculation formula, the shortwave pixel observation value and longwave pixel observation value corresponding to different observation geometric parameters are calculated. The pixel observation simulation value calculation formula takes into account atmospheric parameters, ground cover type and observation geometric parameters.

[0011] Based on the true values ​​of shortwave and longwave radiative flux, and the shortwave and longwave pixel observation values ​​corresponding to different observation geometric parameters, the corresponding pixel observation errors are calculated, and the sensitivity of each pixel observation error to changes in various observation geometric parameters is further calculated.

[0012] The geometric observation error is quantified by averaging the time-based values ​​of the square root mean of all sensitivities.

[0013] Optionally, the expression for the preset pixel observation simulation value calculation formula is:

[0014]

[0015]

[0016]

[0017]

[0018] Among them, MF SW For shortwave pixel observations, MF LW For long-wavelength pixel observations, subscript i represents a sub-node of the object space field of view for a specific pixel, and subscript P represents the entire object space field of view for that pixel. (FSW) i and FLW i These are the true values ​​of the shortwave and longwave radiative fluxes of the top layer of Earth's atmosphere corresponding to sub-node i in the object space field of view of the pixel; PSW i and PLW i , respectively, represent the non-uniformity factors of shortwave and longwave radiation from the top layer of Earth's atmosphere to the lunar surface corresponding to sub-node i in the object space field of view; is the ratio of directional radiance to radiant flux; ISW i and ILW i These represent the directional long-wavelength and short-wavelength radiance of child node i, respectively, FSW i FLW i PSW i PLW i ISW i and ILW i The PSW is closely related to the ground cover type, atmospheric state, and observation geometry of the region where the pixel object space field of view sub-node i is located. P and PLW P D is the radiation non-uniformity factor of the top layer of Earth's atmosphere in the entire pixel object space field of view, obtained by weighting the radiation non-uniformity factors of each sub-node within it. Li Let vz be the distance between the lunar-based observatory and the sub-node i of the pixel object space field of view. i For the zenith angle observed by child node i within the object space field of view of a pixel, ω iLet A be the angle between the view vector of child node i inside the object space field of view and the geocentric observation vector. i Let A represent the area of ​​the top layer of Earth's atmosphere, represented by sub-node i within the pixel's object space field of view. P A represents the field of view area of ​​the entire pixel object space. i With A P vz was obtained by calculating the area integral of the Earth ellipsoid from WGS-84. P For the zenith angle observed from the pixel center, ω P Let D be the angle between the pixel center view vector and the geocentric observation vector. LP This represents the distance from the lunar-based observatory to the pixel center.

[0019] Optionally, the FSW i FLW i PSW i PLW i ISW i and ILW i The model is given by the non-uniform radiation model of the Earth's top of atmosphere-lunar base station.

[0020] Optionally, the method for constructing the non-uniform radiation model of the Earth's atmosphere top-lunar base station includes:

[0021] Acquire information on spatiotemporal disturbances of atmospheric parameters, calculate the response sensitivity of the non-uniformity factor of shortwave and longwave radiation from the top of Earth's atmosphere to the lunar surface to changes in relevant atmospheric parameters, and quantitatively assess the impact of relevant atmospheric state parameters on the non-uniformity factor of radiation from the top of Earth's atmosphere to the lunar base station.

[0022] Acquire time-varying information of various observation geometric parameters of lunar-based observatories, calculate the response sensitivity of the non-uniformity factor of shortwave and longwave radiation from the top of Earth's atmosphere to the lunar surface to changes in various observation geometric parameters, and quantitatively analyze the influence of relevant observation geometric parameters on the non-uniformity factor of radiation from the top of Earth's atmosphere to the lunar-based observatories.

[0023] Based on global land cover data, resampling is performed using the spatial resolution of lunar-based observatories as a benchmark to generate lunar-based observation data on Earth's land cover types. The response of shortwave and longwave radiation non-uniformity factors to changes in land cover types is calculated, and the influence of Earth's land cover types on the radiation non-uniformity factors of the Earth's top of atmosphere-lunar-based observatories is analyzed.

[0024] Optionally, the distance D between the lunar-based observatory and the pixel object space field of view sub-node i is... Li and the distance D from the lunar-based observatory to the pixel center LP Distance parameters are given by NASA JPL DE430 ephemeris data;

[0025] The zenith angle vz observed at the pixel center PThe calculation formula is:

[0026]

[0027] The zenith angle vz observed by the sub-node i within the pixel object space is... i The calculation formula is:

[0028]

[0029] in,

[0030]

[0031]

[0032]

[0033]

[0034] Wherein, γ and These represent the latitude and longitude of the Earth's WGS-84 ellipsoid center projection for pixel object space field of view sub-node i, respectively, and λ V X is the projection point of the lunar-based observatory. i Y i Z i , respectively, are the WGS-84 three-dimensional Cartesian coordinates of the sub-node i in the object space view; P is the ellipsoidal normal vector of the sub-node i in the object space view, and a and b are the semi-axis and semi-major axis of the WGS-84 reference ellipsoid segment, respectively;

[0035] The angle ω between the pixel center view vector and the geocentric observation vector is... P The calculation formula is:

[0036]

[0037]

[0038] The angle ω between the view vector of the pixel object space field of view sub-node i and the geocentric observation vector i The calculation formula is:

[0039]

[0040] Optionally, the formula for calculating the observation error of each pixel is:

[0041] Err SW =MF SW -FSW

[0042] Err LW =MF LW -FLW

[0043] Among them, Err SW and Err LW These represent the shortwave observation error and longwave observation error of a specific pixel, respectively.

[0044] Optionally, the formula for calculating the sensitivity of each pixel's observation error to changes in various observation geometric parameters is as follows:

[0045]

[0046]

[0047] Wherein, MLW is the shortwave pixel observation error, MSW is the longwave pixel observation error, S is the geometric parameter to be evaluated, ΔGY is the change in the geometric parameter to be evaluated, ΔESW and ΔELW are the changes in the shortwave and longwave geometric observation errors, i is the pixel number, and j is the geometric parameter number to be evaluated.

[0048] Optionally, the formula for calculating the quantized value of the geometric observation error is:

[0049]

[0050]

[0051] Wherein, GSW is the quantized value of shortwave geometric observation error, GLW is the quantized value of shortwave geometric observation error, K is the number of pixels, and T is the total number of time nodes within the evaluation period.

[0052] Secondly, the present invention provides a geometric observation error quantification device for a lunar-based Earth radiation detection platform, comprising:

[0053] The truth value acquisition module is used to acquire the truth values ​​of shortwave and longwave radiation flux from the top of Earth's atmosphere to the lunar surface.

[0054] The observation value calculation module is used to continuously change the values ​​of the observation geometric parameters. Based on the true values ​​of shortwave and longwave radiative flux and the preset pixel observation simulation value calculation formula, it calculates the shortwave pixel observation value and longwave pixel observation value corresponding to different observation geometric parameters. The pixel observation simulation value calculation formula takes into account atmospheric parameters, ground cover type and observation geometric parameters.

[0055] The sensitivity calculation module is used to calculate the corresponding pixel observation error based on the true values ​​of shortwave and longwave radiation flux, as well as the shortwave and longwave pixel observation values ​​corresponding to different observation geometric parameters, and further calculate the sensitivity of each pixel observation error to changes in various observation geometric parameters.

[0056] The geometric observation error quantization module is used to calculate the geometric observation error quantization value by performing time averaging based on the square root mean of all sensitivities.

[0057] Thirdly, the present invention provides a geometric observation error quantification system for a lunar-based Earth radiation detection platform, including a storage medium and a processor;

[0058] The storage medium is used to store instructions;

[0059] The processor is configured to operate according to the instructions to perform the method according to any one of the first aspects.

[0060] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0061] Existing research cannot effectively quantify the geometric observation errors of the Earth-based lunar radiation observation system, thus seriously hindering the advancement of research on the mechanism of Earth-based lunar radiation observation and the development of instruments. This is precisely the key problem that this invention aims to solve. Specifically, compared with the prior art, this invention has the following beneficial effects:

[0062] The observation simulation calculation method set by this invention takes into account the influence of atmospheric parameters, ground cover type and observation geometric parameters, which can effectively improve the simulation accuracy of pixel observation values ​​of the Earth Radiation Lunar Observation System.

[0063] This invention fully considers the influence of various geometric parameters when performing sensitivity calculations and effectively eliminates the influence of pixel spatial distribution and time period on the calculation results, which can effectively improve the accuracy of geometric observation error calculation for the Earth Radiation Lunar Base Observation System. Attached Figure Description

[0064] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein:

[0065] Figure 1 This is a flowchart illustrating a method for quantifying geometric observation errors of a lunar-based Earth radiation detection platform according to an embodiment of the present invention. Detailed Implementation

[0066] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0067] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0068] Example 1

[0069] This invention provides a method for quantifying the geometric observation error of an Earth-based lunar radiation detection platform. First, the true values ​​of shortwave and longwave radiation flux from the Earth's upper atmosphere to the lunar surface are obtained. Then, based on these true values, using Jet Propulsion Laboratory (JPL) ephemeris data and function sets, a non-uniform radiation model of the Earth's upper atmosphere-lunar base station and a spatial field-of-view positioning model for the Earth-based lunar radiation observation system's pixels are constructed, and the pixel observation values ​​are calculated. Finally, based on the true values ​​of shortwave and longwave radiation flux and the simulated pixel observation values, the detection error of the Earth-based lunar radiation observation platform is calculated. Then, based on this, the sensitivity of the detection error to changes in various observation geometric parameters of the lunar base platform is comprehensively analyzed, and a method for quantifying the geometric observation error of the Earth-based lunar radiation detection platform is constructed to calculate the quantified value of the geometric observation error.

[0070] Specifically, the following steps are included:

[0071] (1) Obtain the true values ​​of shortwave and longwave radiation flux from the top of Earth's atmosphere to the lunar surface;

[0072] (2) By continuously changing the values ​​of the observation geometric parameters, based on the true values ​​of the radiation flux of shortwave and longwave, and the preset calculation formula for the simulated value of pixel observation, the shortwave pixel observation value and longwave pixel observation value corresponding to different observation geometric parameters are calculated. The calculation formula for the simulated value of pixel observation takes into account atmospheric parameters, ground cover type and observation geometric parameters.

[0073] (3) Based on the true values ​​of radiation flux of shortwave and longwave, and the shortwave and longwave pixel observation values ​​corresponding to different observation geometric parameters, calculate the corresponding pixel observation error, and further calculate the sensitivity of each pixel observation error to the changes of various observation geometric parameters.

[0074] (4) Perform time averaging based on the square root mean of all sensitivities to calculate the quantified value of geometric observation error.

[0075] The following is combined with Figure 1 The geometric observation error quantification method in the embodiments of the present invention will be described in detail.

[0076] Step 1: Determine the true values ​​of shortwave and longwave radiation flux from the top of Earth's atmosphere to the lunar surface.

[0077] In practice, the true values ​​of the reflected shortwave (0.2-4 μm) and emitted longwave (4-100 μm) radiation flux from the Earth’s top atmosphere to the lunar surface will be calculated using the Kriging spatial difference method and the CERES half-cosine time difference method, based on radiation and cloud and atmospheric data from the Cloud and Earth Radiation Observation Satellite (CERES) and global ground cover data from the National Oceanic and Atmospheric Administration (NOAA) (JPSS-VIIRS-AST).

[0078] Step 2: Based on the true value of radiation flux obtained in Step 1, calculate the simulated value of pixel observation.

[0079] The Earth-Lunar Radiation Detection System primarily observes the reflected shortwave (0.2-4 μm) and emitted longwave (4-100 μm) radiation flux from the top of Earth's atmosphere to the lunar surface. The shortwave observation value (MF) of a specific pixel is also measured. SW ) and long-wavelength pixel observations (MF LW This can be obtained by summing the calculation results of discrete child nodes within the object space field of view of this pixel:

[0080]

[0081]

[0082] Where, subscript i represents a sub-node of the object space field of view of a certain pixel, and subscript P represents the entire object space field of view of that pixel. FSW i and FLW i These are the true values ​​of the shortwave and longwave radiative fluxes of the top layer of Earth's atmosphere corresponding to child node i, respectively; PSW i and PLW i These are the non-uniformity factors of shortwave and longwave radiation from the Earth's upper atmosphere to the lunar surface, corresponding to child node i. Physically defined as the ratio of directional radiance to radiant flux, it is typically used to convert between radiance and radiant flux.

[0083]

[0084]

[0085] ISW i and ILW i These represent the directional long-wavelength and short-wavelength radiance of pixel object space field of view sub-node i (pointing from the observed area on Earth to the lunar-based observatory), respectively. i PLW i ISW i ILW i FSW i and FLW i The PSW is related to the atmospheric state, observation geometry, and ground cover type of the observed region, represented by child node i. P and PLW P The TOA (Total Optical Aspect) radiation non-uniformity factor for the entire pixel object space field of view is obtained by weighting the radiation non-uniformity factors of each sub-node within it. Generally, PSW... i PLW i The non-uniform radiation model of the Earth's upper atmosphere-lunar base station can be provided. However, most existing models use simple assumptions and do not fully consider the influence of several key factors, such as atmospheric parameters (e.g., atmospheric optical thickness, cloud type, cloud cover), observation geometry (observation zenith angle, relative azimuth angle, etc.), and Earth's surface cover type (e.g., water bodies, wetlands, artificial surfaces, glaciers, and permanent snow cover). This leads to significant errors in the calculation results. This patent aims to improve upon these shortcomings by fully considering the influence of these factors and constructing a high-precision non-uniform radiation model of the Earth's upper atmosphere-lunar base station. The specific construction steps are as follows:

[0086] 1) Quantitative assessment of the impact of Earth's atmospheric state: Spatiotemporal series analysis of CERES_CldTypHist atmospheric state data will be conducted to obtain spatiotemporal disturbance information of relevant atmospheric parameters (such as atmospheric optical thickness, cloud type, cloud cover, etc.), calculate the response sensitivity of shortwave and longwave radiation nonuniformity factors to changes in relevant atmospheric parameters, and quantitatively assess the impact of relevant atmospheric state parameters on the radiation nonuniformity factor of the Earth's Atmosphere Top-Lunar Base Observatory.

[0087] 2) Quantitative assessment of the impact of observation geometry: It is planned to use JPL ephemeris data to conduct spatial position analysis of the Earth-Moon-based observatory, obtain time-varying information of various observation geometry parameters (observation zenith angle, relative azimuth angle, etc.) of the lunar-based observatory, calculate the response sensitivity of shortwave and longwave radiation non-uniformity factors to changes in various observation geometry parameters, and quantitatively analyze the impact of relevant observation geometry parameters on the radiation non-uniformity factor of the Earth's upper atmosphere-Moon-based observatory.

[0088] 3) Impact assessment of Earth's surface cover type: Based on global surface cover data (such as GlobeLand30_V2020), resampling will be performed using the spatial resolution of lunar-based observatories as a benchmark (proposed to be 1 km, which will be adjusted according to subsequent studies on the spatiotemporal resolution of lunar-based observatories) to generate lunar-based observation data on Earth's surface cover type. The response of shortwave and longwave radiation non-uniformity factors to changes in surface cover type will be calculated, and the impact of Earth's surface cover type on the radiation non-uniformity factor of the Earth's top of atmosphere-lunar-based observatories will be analyzed.

[0089] 4) Finally, based on the comprehensive analysis of the above results, a high-precision model of Earth's top of atmosphere-lunar base station radiation non-uniformity suitable for Earth-based radiation observation systems is constructed to improve the accuracy of non-uniformity factor calculation.

[0090] In equations (1) and (2), N is the number of sub-nodes in the object space field of view of a pixel, which can be obtained from the following equation:

[0091]

[0092] SPS is the spatial resolution of the lunar-based observatory, and SPA is the spatial resolution of the true value of the radiation flux from the top of Earth's atmosphere to the lunar surface.

[0093] In equations (1) and (2), D Li Let vz be the distance between the lunar-based observatory and the sub-node i of the pixel object space field of view. i For the zenith angle observed by child node i within the object space field of view of a pixel, ω i Let A be the angle between the view vector of child node i within the object space field of view (pointing from the observed object to the lunar-based observatory) and the geocentric observation vector (pointing from the geocenter to the lunar-based observatory). i Let A represent the area of ​​the top layer of Earth's atmosphere, represented by sub-node i within the pixel's object space field of view. P A represents the field of view area of ​​the entire pixel object space. i With A P vz was obtained by calculating the area integral of the Earth ellipsoid from WGS-84. P For the zenith angle observed from the pixel center, ω P D is the angle between the pixel center view vector and the geocentric observation vector (pointing from the geocenter to the lunar-based observatory). LP D is the distance from the lunar-based observatory to the pixel center. Li D LP vz i vz P ω i and ω P The pixel observation field of view localization model needs to be constructed and then calculated. The steps for constructing the pixel observation field of view localization model are as follows:

[0094] (1) Calculation of distance and zenith angle: D Li D LP The distance parameter (Ds) can be given by NASA JPL DE430 ephemeris data, vz i vz P It can be calculated using the following formula:

[0095]

[0096]

[0097] in:

[0098]

[0099]

[0100] Wherein, γ and These are the latitude and longitude of the Earth's WGS-84 ellipsoid center projection at observation point i, respectively. The JPLDE430 observation angle parameters can be combined with the SPICE projection angle function (A... CAL Calculation yielded:

[0101]

[0102] Where, λ V The projection point of the lunar-based observatory can be given by the JPL DE430 ephemeris data parameters (sub-MEROlatitude). X i Y i Z i Let be the WGS-84 3D Cartesian coordinates of the sub-node i in the object space view, respectively; P is the ellipsoidal normal vector of the sub-node i in the object space view, which can be calculated by the following formula:

[0103]

[0104] Where a and b are the semi-axis and major semi-axis of the WGS-84 reference ellipsoid segment, respectively.

[0105] (2) Calculation of the angle between the line of sight vector and the geocentric observation vector: ω i and ω P It can be calculated using the following formula:

[0106]

[0107]

[0108] Among them, K O It can be calculated using the following formula:

[0109]

[0110] Step 3: Using the simulated observation values ​​obtained in Step 2 and based on the true values ​​from Step 1, calculate the detection error;

[0111] The detection error of a single pixel is the difference between the observed value and the "true value" of that pixel.

[0112] ESW = MF SW -FSW

[0113] ELW=MF LW -FLW (12)

[0114] Among them, Err SW and Err LW These represent the shortwave observation error and longwave observation error of a specific pixel, respectively. Finally, based on the above formula, the "detection error" of pixels at different locations (such as the center pixel, middle pixel, and boundary pixel) is calculated and compared, obtaining the average value of the pixel detection error and the focal plane distribution. The spatial distribution characteristics of the detector array of the detection error are statistically analyzed, thus providing support for subsequent quantification of the influence of geometric observation characteristics on the detection error.

[0115] Step 4: Using the detection error obtained in Step 3, based on the Jet Propulsion Laboratory (JPL) ephemeris data analysis function set, comprehensively analyze the sensitivity of the detection error to changes in various observation geometric parameters, and finally calculate the quantified value of the geometric observation error.

[0116] Based on the Jet Propulsion Laboratory (JPL) ephemeris data analysis function set, using the SPICE angle analysis module and distance analysis module combined with the pixel object spatial field-of-view positioning model constructed in step 2 of this patent, the time-varying laws of the relative positional relationship between the Moon, Earth, and Sun over long time scales are calculated. These mainly include: lunar orbital geometry, lunar libration, and the Earth-Moon system's orbital characteristics around the Sun, revealing the long-term variation characteristics of the observation geometry (distance, angle, etc.) of the Earth-radiation lunar-based detection system. The lunar orbital geometry, lunar libration, and the Earth-Moon system's orbital characteristics around the Sun can be obtained from the lunar orbital data parameter set (LUNAR-ORBIT) in the JPL DE430 data through Chebyshev polynomial difference calculations. Then, using the aforementioned simulation method of Earth-radiation lunar-based observations and the "true value," the sensitivity of each pixel's shortwave and longwave observation errors to changes in various observation geometric parameters is calculated after controlling variables.

[0117]

[0118]

[0119] Where MLW represents the shortwave pixel observation error, MSW represents the longwave pixel observation error, S represents the geometric parameter to be evaluated, ΔGY represents the change in the geometric parameter to be evaluated, and ΔESW and ΔELW represent the changes in the shortwave and longwave geometric observation errors, respectively. The subscript i represents the pixel number, and j represents the geometric parameter number to be evaluated. The square root mean of the sensitivity of each geometric parameter is calculated, and then the average value of each pixel is obtained to serve as the quantified values ​​of the shortwave (GSW) and longwave (GLW) geometric observation errors of the Earth Radiation Lunar-Based Sounding System.

[0120]

[0121]

[0122] Where K is the number of pixels and T is the total number of time points within the evaluation period.

[0123] Example 2

[0124] Based on the same inventive concept as in Embodiment 1, this embodiment of the invention provides a geometric observation error quantification device for a lunar-based Earth radiation detection platform, comprising:

[0125] The truth value acquisition module is used to acquire the truth values ​​of shortwave and longwave radiation flux from the top of Earth's atmosphere to the lunar surface.

[0126] The observation value calculation module is used to continuously change the values ​​of the observation geometric parameters. Based on the true values ​​of shortwave and longwave radiative flux and the preset pixel observation simulation value calculation formula, it calculates the shortwave pixel observation value and longwave pixel observation value corresponding to different observation geometric parameters. The pixel observation simulation value calculation formula takes into account atmospheric parameters, ground cover type and observation geometric parameters.

[0127] The sensitivity calculation module is used to calculate the corresponding pixel observation error based on the true values ​​of shortwave and longwave radiation flux, as well as the shortwave and longwave pixel observation values ​​corresponding to different observation geometric parameters, and further calculate the sensitivity of each pixel observation error to changes in various observation geometric parameters.

[0128] The geometric observation error quantization module is used to calculate the geometric observation error quantization value by performing time averaging based on the square root mean of all sensitivities.

[0129] The rest are the same as in Example 1.

[0130] Example 3

[0131] This invention provides a geometric observation error quantification system for a lunar-based Earth radiation detection platform, including a storage medium and a processor;

[0132] The storage medium is used to store instructions;

[0133] The processor is configured to operate according to the instructions to execute the method according to any one of Embodiment 1.

[0134] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0135] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0136] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0137] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0138] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

[0139] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A method for quantifying the geometric observation error of a lunar-based Earth radiation detection platform, characterized in that, include: Obtain the true values ​​of shortwave and longwave radiation flux from the top of Earth's atmosphere to the lunar surface; By continuously changing the values ​​of the observation geometric parameters, based on the true values ​​of the shortwave and longwave radiative flux and the preset pixel observation simulation value calculation formula, the shortwave pixel observation value and longwave pixel observation value corresponding to different observation geometric parameters are calculated. The pixel observation simulation value calculation formula takes into account atmospheric parameters, ground cover type and observation geometric parameters. Based on the true values ​​of shortwave and longwave radiative flux, and the shortwave and longwave pixel observation values ​​corresponding to different observation geometric parameters, the corresponding pixel observation errors are calculated, and the sensitivity of each pixel observation error to changes in various observation geometric parameters is further calculated. The geometric observation error is quantified by averaging the time-based values ​​of the square root mean of all sensitivities. The formula for calculating the sensitivity of each pixel's observation error to changes in various observation geometric parameters is as follows: ， ， in, For long-wavelength pixel sensitivity, S represents the shortwave pixel sensitivity, and S represents the geometric parameter to be evaluated. The change in the geometric parameter to be measured. and This represents the variation in geometric observation errors for shortwave and longwave. For pixel number, Number the geometric parameters to be evaluated; The formula for calculating the quantized value of the geometric observation error is as follows: ， ， in, This is the quantization value of the shortwave geometric observation error. This is the quantization value of the shortwave geometric observation error. For the number of pixels, To assess the total number of time points within the evaluation period.

2. The method for quantifying geometric observation errors of a lunar-based Earth radiation detection platform according to claim 1, characterized in that: The expression for the preset pixel observation simulation value calculation formula is: ； ， ， ， in, These are shortwave pixel observations. For long-wavelength pixel observations, subscript For a certain pixel's object space field of view sub-node, the subscript... For the entire field of view of the pixel object space, and These are the sub-nodes of the pixel object space view. The true values ​​of the shortwave and longwave radiation fluxes corresponding to the top layer of Earth's atmosphere; and These are the sub-nodes of the pixel object space view. The corresponding non-uniformity factor of shortwave and longwave radiation from the top of Earth's atmosphere to the lunar surface is the ratio of directional radiance to radiative flux. and These represent the directional long-wavelength radiance and short-wavelength radiance of child node i, respectively. , , , , and With pixel object space field of view sub-node The location is closely related to the type of ground cover, atmospheric conditions, and observation geometry. and The radiation non-uniformity factor of the top layer of Earth's atmosphere in the entire pixel object space field of view is obtained by weighting the radiation non-uniformity factors of each sub-node within it. For lunar-based observatories and pixel-based objects, the spatial field of view sub-nodes distance, For the child nodes inside the object space field of view of the pixel Observe the zenith angle. For the child nodes inside the object space field of view of the pixel The angle between the view vector and the geocentric observation vector, For the child nodes inside the object space field of view of the pixel Represents the area of ​​the top layer of Earth's atmosphere. The field of view of the entire pixel object space. and Calculated using the WGS-84 Earth ellipsoid area integral. To observe the zenith angle from the pixel center, The angle between the pixel center view vector and the geocentric observation vector. This represents the distance from the lunar-based observatory to the pixel center.

3. The method for quantifying geometric observation errors of a lunar-based Earth radiation detection platform according to claim 2, characterized in that: The , , , , and The model is given by the non-uniform radiation model of the Earth's top of atmosphere-lunar base station.

4. The method for quantifying geometric observation errors of a lunar-based Earth radiation detection platform according to claim 3, characterized in that: The method for constructing the non-uniform radiation model of the Earth's upper atmosphere-lunar base station includes: Acquire information on spatiotemporal disturbances of atmospheric parameters, calculate the response sensitivity of the non-uniformity factor of shortwave and longwave radiation from the top of Earth's atmosphere to the lunar surface to changes in relevant atmospheric parameters, and quantitatively assess the impact of relevant atmospheric state parameters on the non-uniformity factor of radiation from the top of Earth's atmosphere to the lunar base station. Acquire time-varying information of various observation geometric parameters of lunar-based observatories, calculate the response sensitivity of the non-uniformity factor of shortwave and longwave radiation from the top of Earth's atmosphere to the lunar surface to changes in various observation geometric parameters, and quantitatively analyze the influence of relevant observation geometric parameters on the non-uniformity factor of radiation from the top of Earth's atmosphere to the lunar-based observatories. Based on global land cover data, resampling is performed using the spatial resolution of lunar-based observatories as a benchmark to generate lunar-based observation data on Earth's land cover types. The response of shortwave and longwave radiation non-uniformity factors to changes in land cover types is calculated, and the influence of Earth's land cover types on the radiation non-uniformity factors of the Earth's top of atmosphere-lunar-based observatories is analyzed.

5. The method for quantifying geometric observation errors of a lunar-based Earth radiation detection platform according to claim 2, characterized in that: The lunar-based observatory and the pixel object space field of view sub-node distance Distance from lunar-based observatory to pixel center Distance parameters are given by NASA JPL DE430 ephemeris data; The zenith angle observed at the pixel center The calculation formula is: ， The field of view sub-node inside the pixel object space Observation zenith angle The calculation formula is ， in, ， ， ， ， in, and These are the sub-nodes of the pixel object space view. Latitude and longitude of the Earth's WGS-84 ellipsoid center projection. For the projection point of the lunar-based observatory, , , These are the sub-nodes of the pixel object space view. WGS-84 three-dimensional Cartesian coordinates; It is a sub-node of the image object space field of view. The ellipsoidal normal vector, , These are the semi-axis and major semi-axis of the WGS-84 reference ellipsoid segment, respectively; The angle between the pixel center view vector and the geocentric observation vector is... The calculation formula is: ， ， The pixel object space field of view sub-node The angle between the view vector and the geocentric observation vector The calculation formula is 。 6. The method for quantifying geometric observation errors of a lunar-based Earth radiation detection platform according to claim 1, characterized in that: The formula for calculating the observation error of each pixel is: ， ， in, and These represent the shortwave observation error and longwave observation error of a specific pixel, respectively.

7. A device for quantifying geometric observation errors of a lunar-based Earth radiation detection platform, characterized in that, include: The truth value acquisition module is used to acquire the truth values ​​of shortwave and longwave radiation flux from the top of Earth's atmosphere to the lunar surface. The observation value calculation module is used to continuously change the values ​​of the observation geometric parameters. Based on the true values ​​of shortwave and longwave radiative flux and the preset pixel observation simulation value calculation formula, it calculates the shortwave pixel observation value and longwave pixel observation value corresponding to different observation geometric parameters. The pixel observation simulation value calculation formula takes into account atmospheric parameters, ground cover type and observation geometric parameters. The sensitivity calculation module is used to calculate the corresponding pixel observation error based on the true values ​​of shortwave and longwave radiation flux, as well as the shortwave and longwave pixel observation values ​​corresponding to different observation geometric parameters, and further calculate the sensitivity of each pixel observation error to changes in various observation geometric parameters. The geometric observation error quantization calculation module is used to perform time averaging based on the square root mean of all sensitivities to calculate the geometric observation error quantization value. The formula for calculating the sensitivity of each pixel's observation error to changes in various observation geometric parameters is as follows: ， ， in, For long-wavelength pixel sensitivity, S represents the shortwave pixel sensitivity, and S represents the geometric parameter to be evaluated. The change in the geometric parameter to be measured. and This represents the variation in geometric observation errors for shortwave and longwave. For pixel number, Number the geometric parameters to be evaluated; The formula for calculating the quantized value of the geometric observation error is as follows: ， ， in, This is the quantization value of the shortwave geometric observation error. This is the quantization value of the shortwave geometric observation error. For the number of pixels, To assess the total number of time points within the evaluation period.

8. A geometric observation error quantification system for a lunar-based Earth radiation detection platform, characterized in that, Including storage media and processor; The storage medium is used to store instructions; The processor is configured to operate according to the instructions to perform the method according to any one of claims 1-6.

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