Method and device for simulating radiance of key detection area of lunar surface

Abstract

The invention provides a lunar surface key detection area radiance simulation method and device, and relates to the technical field of lunar exploration, and the method comprises the steps: determining a simulation spectrum according to a load parameter, obtaining lunar soil reflection characteristics, surface terrain parameters, a solar incident angle and solar spectrum irradiance information of a target area, selecting a corresponding radiance calculation model, and calculating the radiance of the target area. The spectral radiance of the target area at the actual observation moment of the detection load is calculated, the signal-to-noise ratio of target detection is calculated according to the target spectral radiance, the load optical efficiency, the detector parameters and the system noise, and finally the spectral radiance and the detection signal-to-noise ratio of the specific target under different tracks are calculated through iteration and are compared. And selecting a proper detection track and a proper detection opportunity. According to the invention, factors such as lunar surface topography, illumination conditions, reflection characteristics and the like can be comprehensively considered, the change of lunar surface spectral radiance can be accurately simulated, and accurate reference data can be provided for motion compensation of a high-resolution imaging spectrometer.

Description

Technical Field

[0001] The present invention relates to the field of lunar exploration technology, and in particular to a method and device for simulating radiance of a key lunar exploration area. Background Art

[0002] With the rapid development of deep space exploration technology, lunar exploration has become a key strategic priority for major space exploration nations. High-resolution imaging spectrometers, as key payload equipment, play a vital role in lunar exploration missions, providing information on the lunar surface's composition and geological structure. However, existing lunar exploration data still suffers from significant deficiencies in spatial resolution, signal-to-noise ratio, and polar coverage, making it difficult to meet the practical requirements of subsequent deep space exploration missions, such as the site selection of lunar research stations and astronaut route planning.

[0003] At present, high-resolution imaging spectrometers face the following technical difficulties in the process of lunar exploration: First, the terrain of the lunar surface is extremely rugged, making it difficult to achieve efficient and comprehensive coverage of the target area; second, the orbit determination accuracy and speed-to-height ratio changes of lunar exploration satellites are significantly inferior to those of Earth remote sensing satellites, which seriously restricts the quality and efficiency of data acquisition; third, the target signal on the lunar surface is weak, especially in areas with unfavorable lighting conditions such as the polar regions. Although the signal-to-noise ratio can be improved by extending the integration time, this approach is bound to reduce the efficiency of spatial scanning, resulting in a technical contradiction between coverage and signal-to-noise ratio.

[0004] Furthermore, high-resolution lunar imaging spectroscopy often requires a dwell time shorter than the detector's required integration time, necessitating the use of "lead-lag" motion compensation to extend the dwell time and improve the detection signal-to-noise ratio. This improvement in signal-to-noise ratio comes at the cost of shortening the coverage area of ​​a single scan, resulting in no longer continuous, full coverage of key target areas. Furthermore, factors such as illumination and terrain influence the detection process, necessitating the selection of appropriate orbits and detection times from multiple detection trajectories. Therefore, radiance simulation of key lunar detection areas is essential.

[0005] In existing technologies, although motion compensation technology has been widely used in obtaining high-quality imaging spectral remote sensing data, due to the particularity of the lunar exploration environment, such as significant terrain undulations, high compensation magnification requirements, large changes in speed-to-height ratio, and low orbit determination accuracy, the motion compensation technology in the field of Earth remote sensing is difficult to directly transplant to the lunar exploration scenario.

[0006] Furthermore, research on radiance simulation for key lunar exploration areas is still in its infancy. Existing simulation methods cannot effectively integrate multiple factors, such as lunar surface topography, lighting conditions, and the spectral reflectance characteristics of the lunar surface, making it difficult to accurately simulate the dynamic changes in lunar spectral radiance. This technical bottleneck directly affects the accuracy of motion compensation for high-resolution imaging spectrometers, thereby restricting the quality and efficiency of lunar exploration data acquisition. Summary of the Invention

[0007] The purpose of this invention is to provide a method for simulating the radiance of key lunar exploration areas to improve the quality and efficiency of lunar exploration data. This method should comprehensively consider multiple factors, including lunar surface topography, lighting conditions, and reflectance characteristics, to accurately simulate variations in lunar spectral radiance. This method should provide reliable reference data for motion compensation in high-resolution imaging spectrometers, thereby supporting the detailed exploration and development of lunar scientific resources.

[0008] To achieve the above object, the present invention is implemented through the following technical solutions:

[0009] A method for simulating the radiance of a key detection area on the lunar surface comprises the following steps:

[0010] S1: Determine the simulation spectrum and spectral resolution according to the load parameters;

[0011] S2: Obtain lunar soil reflectance characteristics, surface topography parameters, solar incidence angle, and solar spectral irradiance information of the target area;

[0012] S3: selecting a corresponding radiance calculation model according to the simulation spectrum segment;

[0013] S4: Calculating the spectral radiance of the target area at the actual observation time of the detection payload based on the radiance calculation model and the acquired information;

[0014] S5: Calculate the signal-to-noise ratio of target detection based on the target spectral radiance, payload optical efficiency, detector parameters and system noise;

[0015] S6: Iteratively calculate the spectral radiance and detection signal-to-noise ratio of a specific target under different orbits, compare them, and select the appropriate detection orbit and detection time.

[0016] Furthermore, in step S3, when the simulation spectrum is a visible short-wave infrared spectrum, a radiance calculation model that only considers the solar radiation reflected by the lunar soil is selected; the wavelength range of the visible short-wave infrared spectrum is 0.35 μm to 2.2 μm.

[0017] Furthermore, the radiance calculation model considering only the lunar soil reflecting solar radiation is as follows:

[0018]

[0019] in:

[0020] L ref (λ,θ i ,θ r ,φ) is the radiance of the lunar soil reflection spectrum at wavelength λ;

[0021] ρ(λ,θ i ,θ r ,φ) is the bidirectional reflectance distribution function at wavelength λ, which is determined by the lunar soil characteristics and observation geometry;

[0022] E(λ,θ i ) is the wavelength λ, the sun is at an incident angle θ i spectral irradiance under ;

[0023] θ i is the incident angle of sunlight; θ r is the reflection angle; φ is the phase angle between the reflected and incident light.

[0024] Furthermore, in step S3, when the simulation spectrum is a medium- and long-wave infrared spectrum, a radiance calculation model is selected that simultaneously considers the amount of sunlight reflected and the lunar soil's own radiation; the wavelength of the medium- and long-wave infrared spectrum is greater than 2.2 μm.

[0025] Furthermore, the lunar spectral radiance calculation model that simultaneously considers the amount of solar radiation reflected and the lunar soil's own radiation is characterized in that the lunar spectral radiance is calculated using the following formula:

[0026] L total (λ,θ i ,θ r ,φ)=L ref (λ,θ i ,θ r ,φ)+L emit (λ,T)

[0027] in:

[0028] L total (λ,θ i ,θ r ,φ) is the total spectral radiance at wavelength λ;

[0029] L ref (λ,θ i ,θ r ,φ) is the spectral radiance of solar radiation reflected by the lunar soil;

[0030] L emit (λ,T) is the spectral radiance of the lunar soil itself, which is calculated by the following formula:

[0031] L emit (λ,T)=∈(λ)·B(λ,T)

[0032] in:

[0033] ∈(λ) is the lunar soil spectral emissivity at wavelength λ;

[0034] B(λ,T) is the blackbody radiation spectrum brightness based on Planck's law, and T is the lunar soil temperature in Kelvin. The lunar soil temperature can be calculated using the one-dimensional heat conduction equation.

[0035] Furthermore: in step S2, the lunar soil reflection characteristics are the bidirectional reflectivity characteristics of the actual target lunar soil; the surface topography parameters are obtained through the point cloud data of the target area; the solar incidence angle is confirmed by parameters such as the target point load transit time, target longitude and latitude; the solar spectral irradiance is obtained by convolution according to the spectral resolution of the load.

[0036] Furthermore: in step S5, the signal-to-noise ratio of target detection is calculated according to the following formula:

[0037] The solar radiation reflected from the lunar surface is detected by the detector, and the target radiation power P(λ) received by the detector is calculated according to the following formula:

[0038]

[0039] Among them, E(λ,θ i ) is the radiation spectrum of the sun on the lunar surface, τ a is the lunar atmosphere transmittance, θ is the solar altitude angle, ρ is the lunar surface albedo, τ o is the optical efficiency, A d is the area of ​​the detector's photosensitive surface, and F# is the optical system parameter;

[0040] According to the target radiation power, the number of effective signal electrons N generated by the target signal on the detector unit is calculated according to the following formula: s (λ):

[0041]

[0042] Among them, T int is the integration time of the detector, η(λ) is the quantum efficiency, E ph (λ) is the single photon energy;

[0043] According to the number of effective signal electrons, the signal-to-noise ratio SNR(λ) is calculated according to the following formula:

[0044]

[0045] Among them, n read is the readout noise of the detector, N back (λ) is the number of background electrons introduced by background radiation, N dark (λ) is the number of electrons introduced by the detector dark current, N n (λ) is the number of noise electrons calculated based on a typical noise electron model.

[0046] Further: in the step S6, the selection of a suitable detection track represents the best track in the simulation results of the radiance and signal-to-noise ratio of different tracks of the same target area, and the best track is the track with the highest value; the selection of a suitable detection timing corresponds to the same target area, and when considering the motion compensation along the track duty cycle, the detection timing can achieve the target area coverage requirement under the same track, the detection timing includes the start detection time and the end detection time, and the track space duty cycle is the ratio of the detection area to the flight area; the motion compensation parameters of the high-resolution imaging spectrometer are determined based on the spectral radiance and signal-to-noise ratio obtained by calculation; the motion compensation parameters include: the pointing mirror rotation angle sequence and the integration time.

[0047] The present invention also provides a device for simulating the radiance of a key lunar detection area using the above method, comprising:

[0048] A determination unit, used for determining a simulation spectrum segment according to load parameters;

[0049] An acquisition unit is used to obtain lunar soil reflectance characteristics, surface topography parameters, solar incidence angle, and solar spectral irradiance information of the target area;

[0050] A selection unit, configured to select a corresponding radiance calculation model according to the simulation spectrum segment;

[0051] A first calculation unit is configured to calculate the spectral radiance of the target area at the actual observation time of the detection payload based on the radiance calculation model and the acquired information;

[0052] The second calculation unit is used to calculate the signal-to-noise ratio of target detection by combining the payload optical efficiency, detector parameters and system noise;

[0053] a third calculation unit, for calculating the temperature of a target area on the lunar surface using a one-dimensional heat conduction equation;

[0054] The first calculation unit is also used to substitute the temperature into the radiance calculation model to calculate the lunar soil's own radiation.

[0055] Compared with the prior art, the present invention has the following beneficial effects:

[0056] 1. Improving data quality: By comprehensively considering multiple factors such as the lunar surface topography, lighting conditions, and reflective characteristics, the changes in the lunar spectral radiance are accurately simulated, providing reliable data support for motion compensation of the high-resolution imaging spectrometer, and significantly improving the quality of lunar exploration data.

[0057] 2. Enhanced acquisition efficiency: Using the method of the present invention, the spectral radiance of the target area at a specific moment can be calculated more accurately, and the signal-to-noise ratio of the target detection can be calculated accordingly, thereby guiding the setting of motion compensation parameters of the high-resolution imaging spectrometer. While maintaining a high signal-to-noise ratio, the spatial scanning efficiency is improved, thereby enhancing the efficiency of data acquisition.

[0058] 3. Adaptability to complex conditions: Aiming at the special problems existing in lunar exploration, such as significant terrain undulations, high compensation ratio requirements, and large changes in speed-to-height ratio, the method of the present invention can adapt to these complex conditions and provide effective solutions, solving the problem that existing technologies are difficult to directly apply to lunar exploration.

[0059] 4. Flexible response to different spectral bands: The method of the present invention can flexibly respond to different spectral bands. For the visible short-wave infrared band, a radiance calculation model that considers the solar radiation reflected by the lunar soil is selected; for the medium and long-wave infrared band, both the amount of sunlight reflected and the lunar soil's own radiation are considered at the same time, ensuring the accuracy of radiance calculation within different wavelength ranges.

[0060] 5. Supporting Refined Exploration: By accurately calculating the spectral radiance and signal-to-noise ratio of the target area, it provides a basis for setting the motion compensation parameters of the high-resolution imaging spectrometer, thereby supporting the refined exploration and development of lunar scientific resources and providing strong data support for subsequent tasks such as the site selection of lunar scientific research stations and the planning of astronaut activity routes. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 Schematic diagram of a flow chart of a method for simulating radiance of a key lunar detection area according to an embodiment of the present invention; DETAILED DESCRIPTION

[0062] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0063] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0064] The present invention provides a method for simulating the radiance of a key detection area on the lunar surface, comprising the following steps: determining a simulation spectrum segment according to payload parameters; obtaining lunar soil reflection characteristics, surface topography parameters, solar incidence angle, and solar spectral irradiance information of a target area; selecting a corresponding radiance calculation model according to the simulation spectrum segment; calculating the spectral radiance of the target area at the actual observation moment of the detection payload based on the radiance calculation model and the obtained information; and calculating the signal-to-noise ratio of target detection according to the target spectral radiance, payload optical efficiency, detector parameters, and system noise.

[0065] During the implementation of the present invention, the spectral range required for simulation is first determined based on the imaging spectrometer's payload parameters. For the visible short-wave infrared band (0.35 μm to 2.2 μm), a radiance calculation model is selected that accounts for solar radiation reflected from the lunar soil. For the mid- and long-wave infrared band (wavelengths greater than 2.2 μm), a radiance calculation model is selected that considers both solar reflection and the lunar soil's own radiation. This selection allows for a more accurate reflection of the spectral radiance characteristics across different bands.

[0066] Next, relevant information about the target area is obtained, including the reflectance characteristics of the lunar soil, surface topography, solar incidence angle, and solar spectral irradiance. This information can be obtained from existing databases or ground-based experiments. After obtaining this information, these parameters of the target area are used to calculate the spectral radiance of the target area at the time of actual observation by the detection payload based on the selected radiance calculation model. For the mid- and long-wave infrared spectrum, a one-dimensional heat conduction equation is also used to calculate the temperature of the target area on the lunar surface. This temperature is then substituted into the radiance calculation model to calculate the radiation of the lunar soil itself.

[0067] After calculating the spectral radiance of the target area, the signal-to-noise ratio (SNR) of target detection is calculated using a specific formula, combining the optical efficiency of the imaging spectrometer, the parameters of the detector, and the noise level of the system. This formula reflects the impact of system performance on the SNR and provides a reference for motion compensation of the imaging spectrometer.

[0068] Finally, based on the calculated spectral radiance and signal-to-noise ratio, the motion compensation parameters of the high-resolution imaging spectrometer are determined, primarily including the pointing mirror rotation angle sequence and integration time. These parameters can be injected into the payload via commands to ensure optimal detection results for specific detection missions.

[0069] Through the above steps, the present invention can comprehensively consider multiple factors such as the lunar surface topography, lighting conditions, and reflective characteristics, accurately simulate the changes in the lunar surface spectral radiance, and provide precise reference data for motion compensation of high-resolution imaging spectrometers, thereby supporting the detailed exploration and development of lunar scientific resources.

[0070] The above introduction is intended to enable those skilled in the art to quickly understand the key points of the technical solution of the present invention. The technical solution of this application will be described in detail below through specific embodiments.

[0071] A method for simulating the radiance of a key detection area on the lunar surface comprises the following steps:

[0072] S1: Determine the simulation spectrum and spectral resolution according to the load parameters;

[0073] S2: Obtain lunar soil reflectance characteristics, surface topography parameters, solar incidence angle, and solar spectral irradiance information of the target area;

[0074] In one embodiment, the lunar soil reflectance characteristics are the bidirectional reflectivity characteristics of the actual target lunar soil; the surface topography parameters are obtained through point cloud data of the target area; the solar incidence angle is confirmed by parameters such as the target point payload transit time and the target longitude and latitude; the solar spectral irradiance is obtained by convolution according to the spectral resolution of the payload, and the source of the solar spectral irradiance is the extra-atmospheric solar spectral irradiance information provided by (Gueymard, 2018).

[0075] S3: selecting a corresponding radiance calculation model according to the simulation spectrum segment;

[0076] In other embodiments, in step S3, when the simulated spectrum is a visible short-wave infrared spectrum, a radiance calculation model that only considers the solar radiation reflected by the lunar soil is selected; the wavelength range of the visible short-wave infrared spectrum is 0.35 μm to 2.2 μm; when the simulated spectrum is a medium- and long-wave infrared spectrum, a radiance calculation model that simultaneously considers the amount of sunlight reflected and the lunar soil's own radiation is selected; the wavelength of the medium- and long-wave infrared spectrum is greater than 2.2 μm.

[0077] The radiance calculation model considering only the solar radiation reflected by the lunar soil is as follows:

[0078]

[0079] in:

[0080] L ref (λ,θ i ,θ r ,φ) is the radiance of the lunar soil reflection spectrum at wavelength λ;

[0081] ρ(λ,θ i ,θ r ,φ) is the bidirectional reflectance distribution function at wavelength λ, which is determined by the lunar soil characteristics and observation geometry;

[0082] E(λ,θ i ) is the wavelength λ, the sun is at an incident angle θ i Spectral irradiance under ;

[0083] θ i is the incident angle of sunlight; θ r is the reflection angle; φ is the phase angle between the reflected and incident light.

[0084] The lunar surface spectral radiance calculation model that simultaneously considers the amount of solar radiation reflected and the lunar soil's own radiation is characterized in that the lunar surface spectral radiance is calculated using the following formula:

[0085] L total (λ,θ i ,θ r ,φ)=L ref (λ,θ i ,θ r ,φ)+L emit (λ,T)

[0086] in:

[0087] L total (λ,θ i ,θ r ,φ) is the total spectral radiance at wavelength λ;

[0088] L ref (λ,θ i ,θ r ,φ) is the spectral radiance of solar radiation reflected by the lunar soil;

[0089] L emit (λ,T) is the spectral radiance of the lunar soil itself, which is calculated by the following formula:

[0090] L emit (λ,T)=∈(λ)·B(λ,T)

[0091] in:

[0092] ∈(λ) is the lunar soil spectral emissivity at wavelength λ;

[0093] B(λ,T) is the blackbody radiation spectrum brightness based on Planck's law, expressed as:

[0094]

[0095] Where h is Planck's constant; c is the speed of light; k is the speed of light. B is the Boltzmann constant; T is the lunar soil temperature in Kelvin, which can be calculated using the one-dimensional heat conduction equation.

[0096] S4: Calculating the spectral radiance of the target area at the actual observation time of the detection payload based on the radiance calculation model and the acquired information;

[0097] S5: Calculate the signal-to-noise ratio of target detection based on the target spectral radiance, payload optical efficiency, detector parameters and system noise;

[0098] In some other embodiments, the signal-to-noise ratio of target detection is calculated according to the following formula:

[0099] The solar radiation reflected from the lunar surface is detected by the detector, and the target radiation power P(λ) received by the detector is calculated according to the following formula:

[0100]

[0101] Among them, E(λ,θ i ) is the radiation spectrum of the sun on the lunar surface, τ a is the lunar atmosphere transmittance, θ is the solar altitude angle, ρ is the lunar surface albedo, τ o is the optical efficiency, A d is the area of ​​the detector's photosensitive surface, and F# is the optical system parameter;

[0102] According to the target radiation power, the number of effective signal electrons Ns(λ) generated by the target signal on the detector unit is calculated according to the following formula:

[0103]

[0104] Among them, T int is the integration time of the detector, η(λ) is the quantum efficiency, and Eph(λ) is the single photon energy;

[0105] According to the number of effective signal electrons, the signal-to-noise ratio SNR(λ) is calculated according to the following formula:

[0106]

[0107] Among them, n read is the readout noise of the detector, N back (λ) is the number of background electrons introduced by background radiation, Ndark (λ) is the number of electrons introduced by the detector dark current, N n (λ) is the number of noise electrons calculated based on a typical noise electron model.

[0108] S6: Iteratively calculate the spectral radiance and detection signal-to-noise ratio of a specific target under different orbits, compare them, and select the appropriate detection orbit and detection time.

[0109] In other embodiments, in step S6, the selection of a suitable detection orbit represents the best orbit in the simulation results of radiance and signal-to-noise ratio of different orbits of the same target area, and the best orbit is the orbit with the highest value; the selection of a suitable detection timing corresponds to the same target area, and when considering the motion compensation along the orbit duty cycle, the detection timing can achieve the target area coverage requirement under the same orbit, and the detection timing includes the start detection time and the end detection time, and the orbital space duty cycle is the ratio of the detection area to the flight area; the motion compensation parameters of the high-resolution imaging spectrometer are determined based on the spectral radiance and signal-to-noise ratio obtained by calculation; the motion compensation parameters include: the pointing mirror rotation angle sequence and the integration time.

[0110] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made in accordance with the spirit of the present invention are intended to be covered by the scope of protection of the present invention.

Claims

1. A method for simulating the radiance of a key lunar detection area, characterized in that: The following steps are involved: S1: Determine the simulation spectrum and spectral resolution according to the load parameters; S2: Obtain lunar soil reflectance characteristics, surface topography parameters, solar incidence angle, and solar spectral irradiance information of the target area; S3: Selecting a corresponding radiance calculation model according to the simulation spectrum segment; S4: Calculating the spectral radiance of the target area at the actual observation time of the detection payload based on the radiance calculation model and the acquired information; S5: Calculate the signal-to-noise ratio of target detection based on the target spectral radiance, payload optical efficiency, detector parameters and system noise; S6: Iteratively calculate the spectral radiance and detection signal-to-noise ratio of a specific target under different orbits, compare them, and select the appropriate detection orbit and detection time.

2. The method for simulating radiance of a key lunar detection area according to claim 1, characterized in that: In step S3, when the simulation spectrum is the visible short-wave infrared spectrum, a radiance calculation model that only considers the solar radiation reflected by the lunar soil is selected; the wavelength range of the visible short-wave infrared spectrum is 0.35 μm to 2.2 μm.

3. The method for simulating radiance of a key lunar detection area according to claim 2, characterized in that: The radiance calculation model considering only the lunar soil reflecting solar radiation is shown in the following formula: in: L ref (λ,θ i ,θ r ,φ) is the radiance of the lunar soil reflection spectrum at wavelength λ; ρ(λ,θ i ,θ r ,φ) is the bidirectional reflectance distribution function at wavelength λ, which is determined by the lunar soil characteristics and observation geometry; E(λ,θ i ) is the wavelength λ, the sun is at an incident angle θ i Spectral irradiance under ; θ i is the incident angle of sunlight; θ r is the reflection angle; φ is the phase angle between the reflected and incident light.

4. The method for simulating radiance of a key lunar detection area according to claim 3, characterized in that: In step S3, when the simulation spectrum is a medium- and long-wave infrared spectrum, a radiance calculation model is selected that simultaneously considers the amount of sunlight reflected and the lunar soil's own radiation; the wavelength of the medium- and long-wave infrared spectrum is greater than 2.2 μm.

5. The method for simulating radiance of a key lunar detection area according to claim 4, characterized in that: The lunar surface spectral radiance calculation model that simultaneously considers the amount of solar radiation reflected and the lunar soil's own radiation is characterized in that the lunar surface spectral radiance is calculated using the following formula: L total (λ,θ i ,i r ,φ)=L ref (λ,θ i ,i r ,φ)+L emit (λ,T) in: L total (λ,θ i ,θ r ,φ) is the total spectral radiance at wavelength λ; L ref (λ,θ i ,θ r ,φ) is the spectral radiance of solar radiation reflected by the lunar soil; L emit (λ,T) is the spectral radiance of the lunar soil itself, which is calculated by the following formula: L emit (λ,T)=∈(λ)·B(λ,T) in: ∈(λ) is the lunar soil spectral emissivity at wavelength λ; B(λ,T) is the blackbody radiation spectrum brightness based on Planck's law, and T is the lunar soil temperature in Kelvin, which is calculated using the one-dimensional heat conduction equation.

6. The method for simulating radiance of a key lunar detection area according to claim 1, characterized in that: In step S2, the lunar soil reflection characteristics are the bidirectional reflectivity characteristics of the actual target lunar soil; the surface topography parameters are obtained through the point cloud data of the target area; the solar incidence angle is confirmed by parameters such as the target point load transit time, target longitude and latitude, etc.; the solar spectral irradiance is obtained through convolution according to the spectral resolution of the load.

7. The method for simulating radiance of a key lunar detection area according to claim 1, characterized in that: In step S5, the signal-to-noise ratio of target detection is calculated according to the following formula: The solar radiation reflected from the lunar surface is detected by the detector, and the target radiation power P(λ) received by the detector is calculated according to the following formula: Among them, E(λ,θ i ) is the radiation spectrum of the sun on the lunar surface, τ a is the lunar atmosphere transmittance, θ is the solar altitude angle, ρ is the lunar surface albedo, τ o is the optical efficiency, A d is the area of ​​the detector's photosensitive surface, and F# is the optical system parameter; According to the target radiation power, the number of effective signal electrons N generated by the target signal on the detector unit is calculated according to the following formula: s (λ): Among them, T int is the integration time of the detector, η(λ) is the quantum efficiency, E ph (λ) is the energy of a single photon; According to the number of effective signal electrons, the signal-to-noise ratio SNR(λ) is calculated according to the following formula: Among them, n read is the readout noise of the detector, N back (λ) is the number of background electrons introduced by background radiation, N dark (λ) is the number of electrons introduced by the detector dark current, and Nn(λ) is the number of noise electrons calculated based on a typical noise electron model.

8. The method for simulating radiance of a key lunar detection area according to claim 1, characterized in that: In step S6, the selected appropriate detection track represents the track with the best radiance and signal-to-noise ratio simulation results for different tracks of the same target area, and the best track is the track with the highest value. The selected appropriate detection timing corresponds to the detection timing that can achieve the target area coverage requirement under the same track when considering the motion compensation along the track duty cycle for the same target area. The detection timing includes the start detection time and the end detection time. The track space duty cycle is the ratio of the detection area to the flight area. The calculated spectral radiance and signal-to-noise ratio are used to determine motion compensation parameters of a high-resolution imaging spectrometer; the motion compensation parameters include a pointing mirror rotation angle sequence and an integration time.

9. A device using the method for simulating radiance of a lunar key detection area according to any one of claims 1 to 8, characterized in that: include: A determination unit, used for determining a simulation spectrum segment according to load parameters; An acquisition unit is used to obtain lunar soil reflectance characteristics, surface topography parameters, solar incidence angle, and solar spectral irradiance information of the target area; A selection unit, configured to select a corresponding radiance calculation model according to the simulation spectrum segment; A first calculation unit is configured to calculate the spectral radiance of the target area at the actual observation time of the detection payload based on the radiance calculation model and the acquired information; The second calculation unit is used to calculate the signal-to-noise ratio of target detection by combining the payload optical efficiency, detector parameters and system noise; a third calculation unit, for calculating the temperature of a target area on the lunar surface using a one-dimensional heat conduction equation; The first calculation unit is also used to substitute the temperature into the radiance calculation model to calculate the lunar soil's own radiation.

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