High signal-to-noise ratio spectral space-based observation method, device and electronic equipment

Abstract

The application provides a high signal-to-noise ratio spectral space-based observation method, device and electronic equipment, and the method comprises the following steps: calculating a corresponding solar elevation angle range according to the latitude range of a target observation area; calculating a required signal-to-noise ratio range of a spectral band according to the inversion requirement of the target observation area; calculating the integration time in the target observation area according to the signal-to-noise ratio selected in the signal-to-noise ratio range; and calculating the ground speed of the subspace point in combination with the target observation area and the integration time, so as to determine the maneuvering mode of the satellite. The application can carry out space-based multi-spectral or hyperspectral observation in the target observation area, obtain high signal-to-noise ratio image information, form high signal-to-noise ratio output, and meet the remote sensing inversion requirement of the target observation area.

Description

Technical Field

[0001] This invention mainly relates to the field of on-orbit satellite observation technology, and in particular to a high signal-to-noise ratio spectral space-based observation method, device and electronic equipment. Background Technology

[0002] Artificial satellites (generally referred to as satellites) are devices built by humans and launched into space by spacecraft such as rockets and space shuttles, orbiting the Earth or other planets like natural satellites. Earth observation satellites are artificial Earth satellites that observe the Earth and its atmosphere from space. Due to their high viewing angle and wide observation range, Earth observation satellites can effectively obtain various information such as the Earth's surface, atmospheric clouds, ocean environment, vegetation cover, and human activities. Earth observation satellites include Earth resource satellites, military reconnaissance satellites, ocean satellites, and geodetic satellites.

[0003] Earth observation satellites can be used for space-based observation of black soil. Research on the application of hyperspectral remote sensing data in black soil mainly focuses on soil material composition identification and quantitative inversion based on soil spectral reflectance characteristics, analysis of factors influencing soil spectral reflectance characteristics, comprehensive evaluation of land suitability and productivity, soil type classification and mapping, and inversion of vegetation biophysical and biochemical parameters in agriculture. Hyperspectral remote sensing data is widely used in vegetation indices, estimation of photosynthetic effective radiation (EPA) based on leaf area index, analysis of plant biochemical parameters such as chlorophyll and xanthophyll, estimation of vegetation biomass and crop yield, and monitoring of crop diseases and pests.

[0004] The Northeast Black Soil Region of my country is one of the world's three remaining major black soil regions, having undergone tens of thousands of years of transformation from meadows to grasslands. Under the cold climate of Northeast China, the lush vegetation of meadows and grasslands eroded and gradually accumulated into a thick layer of humus, forming fertile black soil. Conventional Earth spectral observation satellites often use fixed pushbroom modes, and their signal-to-noise ratio (SNR) is related to the instrument, atmospheric transmission model, and observation mode. However, due to the high latitude, low solar altitude angle, and complex surface cover of Northeast my country, conventional satellite Earth observation methods are insufficient to improve the SNR of spectral observations in the black soil region. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a high signal-to-noise ratio spectral space-based observation method, device and electronic equipment, which can carry out space-based multispectral or hyperspectral observation in the target observation area, acquire high signal-to-noise ratio image information, form high signal-to-noise ratio output, and meet the remote sensing inversion requirements of the target observation area.

[0006] To address the aforementioned technical problems, in a first aspect, the present invention provides a high signal-to-noise ratio (SNR) spectral space-based observation method, comprising: calculating the corresponding solar altitude angle range based on the latitude range of the target observation area; calculating the required SNR range of the spectral band based on the inversion requirements of the target observation area; calculating the integration time in the target observation area based on the SNR taken within the SNR range; and calculating the nadir ground velocity by combining the target observation area and the integration time, wherein the nadir ground velocity is used to determine the satellite's maneuvering mode.

[0007] Optionally, calculating the corresponding solar altitude angle range based on the latitude range of the target observation area includes: determining the low-latitude solar altitude angle of the target observation area, and then determining the high-latitude solar altitude angle of the target observation area, or determining the high-latitude solar altitude angle of the target observation area, and then determining the low-latitude solar altitude angle of the target observation area; thus obtaining the solar altitude angle range.

[0008] Optionally, the low-latitude solar altitude angle or the high-latitude solar altitude angle of the target observation area can be determined in the following way:

[0009]

[0010] In the formula, θ is the solar altitude angle. δ is the latitude of the target observation area, τ is the solar declination, and τ is the local time angle of the target observation area.

[0011] Optionally, calculating the required signal-to-noise ratio range of the spectral band based on the inversion requirements of the target observation area includes: calculating the radiance characteristics based on the surface reflectance and the solar altitude angle, and then calculating the signal-to-noise ratio based on the radiance characteristics.

[0012] Optionally, the calculation of radiance characteristics based on surface reflectance and solar altitude angle includes:

[0013] S(r,θ)=a0+a1*r+a2*r 2 +a3*r 3 +b1*θ+b2*θ 2 +b3*θ 3

[0014] In the formula, r is the surface reflectance, θ is the solar altitude angle, and a0 to b3 are fitting coefficients.

[0015] Optionally, the fitting coefficients can be obtained by using the atmospheric radiative transfer program MODTRAN4 to estimate the spectral radiance of ground targets with different reflectivities reaching the top of the atmosphere at different solar altitude angles.

[0016] Optionally, calculating the signal-to-noise ratio based on the radiance characteristics includes:

[0017] SNR(S,t,n)=(S,t) 2 If n∈[n1,n2,n3]

[0018] In the formula, SNR is the signal-to-noise ratio, S is the radiance characteristic, t is the integration time, n is the noise characteristic, n1 is the photon shot noise, n2 is the dark current noise, and n3 is the fixed pattern noise.

[0019] Optionally, calculating the signal-to-noise ratio based on the radiance characteristics includes:

[0020] SNR(S,t,n)=(S,t), if n∈[n4,n5,n6]

[0021] In the formula, SNR is the signal-to-noise ratio, S is the radiance characteristic, t is the integration time, n is the noise characteristic, n4 is the reset noise, n5 is the circuit readout noise, and n6 is the quantization noise.

[0022] Optionally, it also includes: calculating the ground velocity multiple based on the ground velocity at the sub-satellite point.

[0023] Optionally, the step of calculating the ground velocity reduction factor based on the ground velocity at the sub-satellite point further includes: rounding the ground velocity reduction factor to the nearest integer.

[0024] Secondly, the present invention provides a high signal-to-noise ratio (SNR) spectral space-based observation device, comprising: a first calculation module for calculating the corresponding solar altitude angle range based on the latitude range of the target observation area; a second calculation module for calculating the required SNR range of the spectral band based on the inversion requirements of the target observation area; a third calculation module for calculating the integration time in the target observation area based on the SNR taken within the SNR range; and a fourth calculation module for calculating the nadir ground velocity by combining the target observation area and the integration time, wherein the nadir ground velocity is used to determine the satellite's maneuvering mode.

[0025] Thirdly, the present invention provides an electronic device comprising: a processor and a memory, the memory storing a program or instructions executable on the processor, the program or instructions being executed by the processor to implement the steps of the high signal-to-noise ratio spectroscopic space-based observation method as described in the first aspect.

[0026] Fourthly, the present invention provides a readable storage medium on which a program or instructions are stored, which, when executed by a processor, implement the steps of the high signal-to-noise ratio spectroscopic space-based observation method as described in the first aspect.

[0027] Compared with existing technologies, the present invention has the following advantages: First, the corresponding solar altitude angle range is calculated based on the latitude range of the target observation area; then, the signal-to-noise ratio range of the required spectral band is calculated based on the inversion requirements of the target observation area; next, the integration time in the target observation area is calculated based on the signal-to-noise ratio determined within the range; finally, the nadir velocity is calculated by combining the target observation area and the integration time. The nadir velocity is used to determine the satellite's maneuvering mode, thereby enabling space-based multispectral or hyperspectral observations to be carried out in the target observation area, obtaining high signal-to-noise ratio image information to form a high signal-to-noise ratio output, thus meeting the remote sensing inversion requirements of the target observation area. Attached Figure Description

[0028] The accompanying drawings are included to provide a further understanding of this application; they are incorporated into and constitute a part of this application. The drawings illustrate embodiments of this application and, together with this specification, serve to explain the principles of this application. In the drawings:

[0029] Figure 1 This is a flowchart illustrating a high signal-to-noise ratio spectral space-based observation method according to an embodiment of the present invention;

[0030] Figure 2 This is a schematic diagram of the calculation parameters of the solar altitude angle in one embodiment of the present invention;

[0031] Figure 3 This is a schematic diagram of the structure of a high signal-to-noise ratio spectral space-based observation device according to an embodiment of the present invention;

[0032] Figure 4 This is a schematic diagram of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0033] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are merely some examples or embodiments of this application. For those skilled in the art, these drawings can be applied to other similar scenarios without creative effort. Unless obvious from the context or otherwise specified, the same reference numerals in the drawings represent the same structures or operations.

[0034] As indicated in this application and claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" are not specifically singular and may include plural forms. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of explicitly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements.

[0035] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, these terms have no special meaning and therefore should not be construed as limiting the scope of protection of this application. In addition, although the terminology used in this application is selected from commonly known and used terms, some terms mentioned in this application's specification may have been chosen by the applicant according to his or her judgment, and their detailed meanings are explained in the relevant sections of this description. Moreover, this application should be understood not only through the actual terms used, but also through the meaning implied by each term.

[0036] Flowcharts are used in this application to illustrate the operations performed by the system according to embodiments of this application. It should be understood that the preceding or following operations are not necessarily performed in exact order. Instead, various steps can be processed in reverse order or simultaneously. Furthermore, other operations may be added to these processes, or one or more steps may be removed from these processes.

[0037] Example 1

[0038] Figure 1 This is a flowchart illustrating a high signal-to-noise ratio spectral space-based observation method according to an embodiment of the present invention. This method can be applied to the black soil region of Northeast my country, but is not limited thereto.

[0039] refer to Figure 1 The method 100 shown includes: S110, calculating the corresponding solar altitude angle range based on the latitude range of the target observation area; S120, calculating the signal-to-noise ratio range of the required spectral band based on the inversion requirements of the target observation area; S130, calculating the integration time in the target observation area based on the signal-to-noise ratio taken within the signal-to-noise ratio range; S140, calculating the nadir ground velocity by combining the target observation area and the integration time, wherein the nadir ground velocity is used to determine the satellite's maneuvering mode.

[0040] Conventional satellite maneuvers (including speed and frequency) are generally performed according to pre-set or predetermined patterns. Because they don't adapt to the specific conditions of the target observation area, the observation results are less than ideal for certain special regions. For example, in Northeast my country, with its high latitude, low solar altitude angle, and complex surface cover, conventional satellite Earth observation modes are clearly unsuitable for accurately observing the actual conditions of the area.

[0041] In this embodiment, in order to more accurately observe the actual situation of the target observation area and better meet the soil or crop inversion requirements of the target observation area, as a flexible maneuvering method, the ground velocity suitable for the target observation area can be obtained, thereby enabling space-based multispectral or hyperspectral observations to be carried out in the target observation area to obtain high signal-to-noise ratio image information and form a high signal-to-noise ratio output.

[0042] In one example, the calculation of the corresponding solar altitude angle range based on the latitude range of the target observation area can be as follows: determine the low-latitude solar altitude angle of the target observation area, and then determine the high-latitude solar altitude angle of the target observation area, or determine the high-latitude solar altitude angle of the target observation area, and then determine the low-latitude solar altitude angle of the target observation area; and then obtain the solar altitude angle range.

[0043] In this embodiment, regardless of whether the low-latitude solar altitude angle of the target observation area is obtained first or the high-latitude solar altitude angle is obtained first, the corresponding solar altitude angle range can be obtained through the difference between the two solar altitude angles.

[0044] In one example, the low-latitude or high-latitude solar altitude angle of the target observation area can be determined in the following way:

[0045]

[0046] In the formula, θ is the solar altitude angle. Here, δ represents the latitude of the target observation area, τ represents the solar declination, and τ represents the local time angle of the target observation area. (For reference...) Figure 2 As shown, Figure 2 This is a schematic diagram illustrating the calculation parameters of the solar altitude angle in one embodiment of the present invention. For example, In the formula, L1 represents the low latitude of the target observation area, L2 represents the high latitude of the target observation area, and [L1,L2] represents the latitudinal range of the target observation area. θ L2 -θ L1 The solar altitude angle range for the target observation area.

[0047] In one example, the signal-to-noise ratio range of the required spectral band can be calculated based on the inversion requirements of the target observation area by: calculating the radiance characteristics based on the surface reflectance and solar altitude angle, and then calculating the signal-to-noise ratio based on the radiance characteristics.

[0048] Furthermore, the radiance characteristics can be calculated based on surface reflectance and solar altitude angle as follows: S(r,θ)=a0+a1*r+a2*r 2 +a3*r 3 +b1*θ+b2*θ 2 +b3*θ 3In the formula, r is the surface reflectance, θ is the solar altitude angle, and a0 to b3 are fitting coefficients.

[0049] Furthermore, the fitting coefficients can be obtained by using the atmospheric radiative transfer algorithm MODTRAN4 to estimate the spectral radiance of ground targets with different reflectivities reaching the top of the atmosphere at different solar altitude angles. MODTRAN is a medium spectral resolution atmospheric transmittance and radiative transfer algorithm and computational model.

[0050] In this embodiment, different spectral observation requirements necessitate different signal-to-noise ratios (SNRs), and meeting these conditions is based on the soil or crop inversion requirements of the target observation area. Therefore, in this embodiment, radiance characteristics can be calculated based on surface reflectance and solar altitude angle, and then the SNR can be calculated based on these radiance characteristics.

[0051] In one example, the signal-to-noise ratio can be calculated based on radiance characteristics as follows:

[0052] SNR(S,t,n)=(S,t) 2 If n∈[n1,n2,n3]

[0053] In the formula, SNR is the signal-to-noise ratio, S is the radiance characteristic, t is the integration time, n is the noise characteristic, n1 is the photon shot noise, n2 is the dark current noise, and n3 is the fixed pattern noise.

[0054] In another example, the signal-to-noise ratio can also be calculated based on the radiance characteristics:

[0055] SNR(S,t,n)=(S,t), if n∈[n4,n5,n6]

[0056] In the formula, SNR is the signal-to-noise ratio, S is the radiance characteristic, t is the integration time, n is the noise characteristic, n4 is the reset noise, n5 is the circuit readout noise, and n6 is the quantization noise.

[0057] Therefore, in this embodiment, the signal-to-noise ratio (SNR) of different signal-to-noise ratio (SNR) models can be characterized by a first-order correlation with radiance characteristics and integration time, or by a second-order correlation with radiance characteristics and integration time.

[0058] The signal-to-noise ratio calculated based on radiance characteristics can be expressed as:

[0059]

[0060] Of course, those skilled in the art will understand that other signal-to-noise ratio models can also be used, which will not be listed here.

[0061] In one example, the method of this embodiment also calculates the ground velocity reduction factor based on the ground velocity at the nadir point. Further, the ground velocity reduction factor can be rounded down.

[0062] For example, the integration time in the nadir observation area can be calculated based on the signal-to-noise ratio: t = x * a / v, where a is the pixel size, x is a multiple of the ground velocity, and v is the image plane movement velocity. Here, v is related to the nadir velocity v0. G The orbital height H and the focal length f of the camera's optical system are related: v = v G *f / H. The multiple of the ground speed x = INT(SNR) min (S,n)*v / a), where INT represents integer rounding.

[0063] The implementation of this embodiment will be explained in more detail below through a specific application example.

[0064] Step 1: Calculate the solar altitude angle.

[0065] Taking a certain county as an example, with a latitude of 44°24′ and a local time of 13:30 on March 3rd, calculate the solar declination angle:

[0066]

[0067] Where t is the time interval from the vernal equinox, we get δ = -6°57′; local time angle τ = 22°30′; at this time, the spring solar altitude angle is calculated as:

[0068]

[0069] Step 2: Calculate the integration time.

[0070] The camera was designed with a pixel size of 6.4 μm, a focal length of 1200 mm, an entrance pupil diameter of 360 mm, a quantum efficiency of 0.6, an orbital altitude of 500 km, and a ground speed of 6.7 km / s. The signal-to-noise ratio range for a specific spectral band (620 nm–810 nm) was calculated. Based on surface reflectivity and solar altitude angle, the radiance at the entrance pupil was calculated as: L = 0.002383 W / cm². 2 / sr.

[0071] When the signal-to-noise ratio is 400, the required integration time is: t = xa / v, then t = 1.725ms.

[0072] Step 3: Calculate the ground speed factor.

[0073] At this moment, the velocity of the image plane is: v = v G f / H = 0.01608 m / s; therefore, the ground velocity multiple is: x = vt / a = 4.33. Rounding down, x = 4.

[0074] The high signal-to-noise ratio (SNR) spectral space-based observation method provided in this embodiment first calculates the corresponding solar altitude angle range based on the latitude range of the target observation area; then, it calculates the required SNR range of the spectral bands according to the inversion requirements of the target observation area; next, it calculates the integration time in the target observation area based on the SNR determined within the SNR range; finally, it calculates the nadir ground velocity by combining the target observation area and the integration time. The nadir ground velocity is used to determine the satellite's maneuvering mode, thereby enabling space-based multispectral or hyperspectral observations to be carried out in the target observation area, acquiring high SNR image information to form a high SNR output, thus meeting the remote sensing inversion requirements of the target observation area.

[0075] Example 2

[0076] Figure 3 This is a schematic diagram of a high signal-to-noise ratio spectroscopic space-based observation device according to an embodiment of the present invention. (Refer to...) Figure 3 The device 300 shown mainly includes:

[0077] The first calculation module 301 is used to calculate the corresponding solar altitude angle range based on the latitude range of the target observation area; the second calculation module 302 is used to calculate the signal-to-noise ratio range of the required spectral band based on the inversion requirements of the target observation area; the third calculation module 303 is used to calculate the integration time in the target observation area based on the signal-to-noise ratio taken within the specified range; and the fourth calculation module 304 is used to calculate the nadir ground velocity by combining the target observation area and the integration time, wherein the nadir ground velocity is used to determine the satellite's maneuvering mode.

[0078] In one example, calculating the corresponding solar altitude angle range based on the latitude range of the target observation area may include: determining the low-latitude solar altitude angle of the target observation area and then determining the high-latitude solar altitude angle of the target observation area, or determining the high-latitude solar altitude angle of the target observation area and then determining the low-latitude solar altitude angle of the target observation area; thus obtaining the solar altitude angle range.

[0079] In one example, the low-latitude or high-latitude solar altitude angle of the target observation area is determined in the following way:

[0080]

[0081] In the formula, θ is the solar altitude angle. δ represents the latitude of the target observation area, τ represents the solar declination, and τ represents the local time angle of the target observation area.

[0082] In one example, calculating the required signal-to-noise ratio range of the spectral band based on the inversion requirements of the target observation area may include: calculating the radiance characteristics based on the surface reflectance and solar altitude angle, and then calculating the signal-to-noise ratio based on the radiance characteristics.

[0083] In one example, calculating radiance characteristics based on surface reflectance and solar altitude angle includes:

[0084] S(r,θ)=a0+a1*r+a2*r 2 +a3*r 3 +b1*θ+b2*θ 2 +b3*θ 3

[0085] In the formula, r is the surface reflectance, θ is the solar altitude angle, and a0 to b3 are fitting coefficients.

[0086] In one example, the fitting coefficients can be obtained by using the atmospheric radiative transfer program MODTRAN4 to estimate the spectral radiance of ground targets with different reflectivities reaching the top of the atmosphere at different solar altitude angles.

[0087] In one example, calculating the signal-to-noise ratio based on radiance characteristics includes:

[0088] SNR(S,t,n)=(S,t) 2 If n∈[n1,n2,n3]

[0089] In the formula, SNR is the signal-to-noise ratio, S is the radiance characteristic, t is the integration time, n is the noise characteristic, n1 is the photon shot noise, n2 is the dark current noise, and n3 is the fixed pattern noise.

[0090] In one example, calculating the signal-to-noise ratio based on radiance characteristics includes:

[0091] SNR(S,t,n)=(S,t), if n∈[n4,n5,n6]

[0092] In the formula, SNR is the signal-to-noise ratio, S is the radiance characteristic, t is the integration time, n is the noise characteristic, n4 is the reset noise, n5 is the circuit readout noise, and n6 is the quantization noise.

[0093] In one example, it may also include calculating the ground velocity multiple based on the ground velocity at the nadir point.

[0094] In one example, calculating the ground velocity multiple based on the ground velocity at the sub-satellite point can also include rounding the ground velocity multiple.

[0095] For details of other operations performed by each module in this embodiment, please refer to the foregoing embodiments, which will not be elaborated here.

[0096] The high signal-to-noise ratio (SNR) spectral space-based observation device provided in this embodiment first calculates the corresponding solar altitude angle range based on the latitude range of the target observation area; then, it calculates the required SNR range of the spectral bands according to the inversion requirements of the target observation area; next, it calculates the integration time in the target observation area based on the SNR determined within the SNR range; finally, it calculates the nadir ground velocity by combining the target observation area and the integration time. The nadir ground velocity is used to determine the satellite's maneuvering mode, thereby enabling space-based multispectral or hyperspectral observations to be carried out in the target observation area, acquiring high SNR image information to form a high SNR output, thus meeting the remote sensing inversion requirements of the target observation area.

[0097] The high signal-to-noise ratio (SNR) spectral space-based observation device in this application embodiment can be a device, or a component, integrated circuit, or chip in a terminal. The high SNR spectral space-based observation device in this application embodiment can be a device with an operating system. This operating system can be Android, iOS, or other possible operating systems; this application embodiment does not specifically limit its application.

[0098] This application also provides an electronic device, including: a memory for storing programs or instructions executable by a processor; and a processor for executing the programs or instructions to implement the various processes of the above-described high signal-to-noise ratio spectral space-based observation method embodiments, and achieving the same technical effects. To avoid repetition, these will not be described again here.

[0099] Figure 4 This is a schematic diagram of an electronic device according to an embodiment of the present invention. The electronic device 400 may include an internal communication bus 401, a processor 402, a read-only memory (ROM) 403, a random access memory (RAM) 404, and a communication port 405. When applied to a personal computer, the electronic device 400 may also include a hard disk 406. The internal communication bus 401 enables data communication between components of the electronic device 400. The processor 402 can perform judgments and issue prompts. In some embodiments, the processor 402 may consist of one or more processors. The communication port 405 enables data communication between the electronic device 400 and external devices. In some embodiments, the electronic device 400 can send and receive information and data from a network through the communication port 405. The electronic device 400 may also include different forms of program storage units and data storage units, such as the hard disk 406, the read-only memory (ROM) 403, and the random access memory (RAM) 404, capable of storing various data files used for computer processing and / or communication, as well as possible programs or instructions executed by the processor 402. The result processed by processor 402 is transmitted to the user equipment through communication port 405 and displayed on the user interface.

[0100] The aforementioned high signal-to-noise ratio spectral space-based observation method can be implemented as a computer program, stored in hard disk 406, and recorded in processor 402 for execution, in order to implement any of the high signal-to-noise ratio spectral space-based observation methods in this application.

[0101] Similarly, it should be noted that, in order to simplify the description of the present application and thus aid in the understanding of one or more embodiments of the invention, the foregoing description of the embodiments of the present application sometimes combines multiple features into a single embodiment, drawing, or description thereof. However, this disclosure method does not imply that the subject matter of the application requires more features than those mentioned in the claims. In fact, the embodiments contain fewer features than all the features of the single embodiments disclosed above.

[0102] In some embodiments, numbers describing the quantity of components and attributes are used. It should be understood that such numbers used in the description of embodiments are modified in some examples with the terms "approximately," "approximately," or "generally." Unless otherwise stated, "approximately," "approximately," or "generally" indicates that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, which may be changed depending on the characteristics required by individual embodiments. In some embodiments, numerical parameters should take into account specified significant digits and employ a general method of digit reservation. Although the numerical ranges and parameters used to confirm their breadth of scope in some embodiments of this application are approximate values, in specific embodiments, such values ​​are set as precisely as feasible.

[0103] Although this application has been described with reference to specific embodiments, those skilled in the art should recognize that the above embodiments are only used to illustrate this application, and various equivalent changes or substitutions can be made without departing from the spirit of this application. Therefore, any changes or modifications to the above embodiments within the essential spirit of this application will fall within the scope of the claims of this application.

Claims

1. A high signal-to-noise ratio spectroscopic space-based observation method, characterized in that, include: Calculate the corresponding solar altitude angle range based on the latitude range of the target observation area; The required signal-to-noise ratio range of the spectral bands is calculated based on the inversion requirements of the target observation area. The integration time in the target observation area is calculated based on the signal-to-noise ratio (SNR) within the range and the SNR model, wherein the SNR model characterizes the relationship between the SNR, radiance characteristics, and integration time. The nadir ground velocity is calculated by combining the target observation area and the integration time. The nadir ground velocity is used to determine the satellite's maneuvering mode.

2. The high signal-to-noise ratio spectroscopic space-based observation method as described in claim 1, characterized in that, The calculation of the corresponding solar altitude angle range based on the latitude range of the target observation area includes: Determine the low-latitude solar altitude angle of the target observation area, and then determine the high-latitude solar altitude angle of the target observation area, or determine the high-latitude solar altitude angle of the target observation area, and then determine the low-latitude solar altitude angle of the target observation area; thus obtaining the range of solar altitude angles.

3. The high signal-to-noise ratio spectroscopic space-based observation method as described in claim 1, characterized in that, The low-latitude or high-latitude solar altitude angle of the target observation area is determined using the following method: In the formula, θ The solar altitude angle, The latitude value of the target observation area. δ The solar declination, τ The local time angle of the target observation area.

4. The high signal-to-noise ratio spectroscopic space-based observation method as described in claim 1, characterized in that, The calculation of the required signal-to-noise ratio range for the spectral band based on the inversion requirements of the target observation area includes: The radiance characteristics are calculated based on the surface reflectance and the solar altitude angle, and then the signal-to-noise ratio is calculated based on the radiance characteristics.

5. The high signal-to-noise ratio spectroscopic space-based observation method as described in claim 4, characterized in that, The calculation of radiance characteristics based on surface reflectance and solar altitude angle includes: In the formula, r For surface reflectance, θ The solar altitude angle, a 0 to b 3 represents the fitting coefficient.

6. The high signal-to-noise ratio spectroscopic space-based observation method as described in claim 5, characterized in that, The fitting coefficients are obtained by using the atmospheric radiative transfer program MODTRAN4 to estimate the spectral radiance of ground targets with different reflectivities reaching the top of the atmosphere at different solar altitude angles.

7. The high signal-to-noise ratio spectroscopic space-based observation method as described in claim 5, characterized in that, The calculation of the signal-to-noise ratio based on the radiance characteristics includes: In the formula, SNR For signal-to-noise ratio, S For radiance characteristics, t For integration time, n For noise characteristics, n 1 represents photon shot noise. n 2 represents dark current noise. n 3 represents fixed graphic noise.

8. The high signal-to-noise ratio spectroscopic space-based observation method as described in claim 5, characterized in that, The calculation of the signal-to-noise ratio based on the radiance characteristics includes: In the formula, SNR For signal-to-noise ratio, S For radiance characteristics, t For integration time, n For noise characteristics, n 4 represents reset noise. n 5 represents the circuit readout noise. n 6 represents quantization noise.

9. The high signal-to-noise ratio spectroscopic space-based observation method as described in claim 1, characterized in that, Also includes: Calculate the ground speed multiple based on the ground speed at the sub-satellite point.

10. The high signal-to-noise ratio spectroscopic space-based observation method as described in claim 9, characterized in that, The calculation of the ground velocity reduction factor based on the ground velocity at the sub-satellite point also includes: rounding the ground velocity reduction factor to the nearest integer.

11. A high signal-to-noise ratio spectroscopic space-based observation device, characterized in that, include: The first calculation module is used to calculate the corresponding solar altitude angle range based on the latitude range of the target observation area; The second calculation module is used to calculate the signal-to-noise ratio range of the required spectral bands based on the inversion requirements of the target observation area. The third calculation module is used to calculate the integration time in the target observation area based on the signal-to-noise ratio determined in the signal-to-noise ratio range and the signal-to-noise ratio model, wherein the signal-to-noise ratio model characterizes the relationship between the signal-to-noise ratio, radiance characteristics and integration time; The fourth calculation module is used to calculate the nadir ground velocity by combining the target observation area and the integration time. The nadir ground velocity is used to determine the satellite's maneuvering mode.

12. An electronic device, characterized in that, include: A processor and a memory, the memory storing a program or instructions executable on the processor, the program or instructions, when executed by the processor, implementing the steps of the high signal-to-noise ratio spectroscopic space-based observation method as described in any one of claims 1-10.

13. A readable storage medium, characterized in that, The readable storage medium stores a program or instructions that, when executed by a processor, implement the steps of the high signal-to-noise ratio spectroscopic space-based observation method as described in any one of claims 1-10.

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