A method, device, equipment and medium for determining long-distance atmospheric transmission characteristics

Abstract

The present invention discloses a method, device, equipment and medium for determining long-distance atmospheric transmission characteristics, and relates to the technical field of atmospheric transmission characteristic calculation, so as to solve the problem that the atmospheric transmittance above 100 km cannot be calculated in the prior art. The method comprises: obtaining atmospheric parameters within a first target altitude range; determining the atomic gas absorption coefficient and the molecular gas absorption coefficient corresponding to each altitude based on gas components, number density, first absorption cross section and second absorption cross section; summing and calculating the atomic gas absorption coefficient and the molecular gas absorption coefficient to obtain the mixed gas absorption coefficient; and determining the atmospheric transmittance within the first target altitude range using an atmospheric transmission function according to the mixed gas absorption coefficient. The method for determining long-distance atmospheric transmission characteristics provided by the present invention is used to realize the accurate calculation of atmospheric transmittance above 100 km.

Description

Technical Field

[0001] The present invention relates to the technical field of atmospheric transmission characteristic calculation, and in particular to a method, device, equipment and medium for determining long-distance atmospheric transmission characteristics. Background Art

[0002] Atmospheric transmission characteristics refer to the law of radiation energy attenuation when electromagnetic waves are transmitted in the atmosphere. MODTRAN software is usually used to calculate atmospheric transmission characteristics. However, the calculation model of MODTRAN software currently only supports the simulation of atmospheric transmission characteristics within an altitude range of 100km. In space-based detection activities, the operating altitude of satellites is usually between 400-500km. This altitude range far exceeds the calculation capacity of MODTRAN, resulting in the inability to effectively simulate the influence of atmospheric gas components within the range of 400-500km on the transmission characteristics. Therefore, it is impossible to calculate the atmospheric transmission characteristics above 100km. Summary of the invention

[0003] The purpose of the present invention is to provide a method, device, equipment and medium for determining long-distance atmospheric transmission characteristics, which are used to calculate the atmospheric transmittance above 100 km.

[0004] In order to achieve the above object, the present invention provides the following technical solutions:

[0005] In a first aspect, the present invention provides a method for determining long-distance atmospheric transmission characteristics, comprising:

[0006] Acquire atmospheric parameters within a first target altitude range; the first target altitude range is greater than 100 km; the atmospheric parameters include gas components, number densities corresponding to each gas component, first absorption cross sections of atomic gas at different wavelengths, and second absorption cross sections of molecular gas at different wavelengths;

[0007] Determine the atomic gas absorption coefficient and the molecular gas absorption coefficient corresponding to each height based on the gas composition, number density, first absorption cross section and second absorption cross section;

[0008] The atomic gas absorption coefficient and the molecular gas absorption coefficient are summed and calculated to obtain a mixed gas absorption coefficient;

[0009] According to the mixed gas absorption coefficient, an atmospheric transmission function is used to determine the atmospheric transmittance within a first target height range; the atmospheric transmittance is used to reflect the atmospheric transmission characteristics.

[0010] Optionally, before acquiring the atmospheric parameters within the first target altitude range, the step further includes:

[0011] Get the HITRAN database;

[0012] The SCLB model is used to expand the gas spectral line parameters in the HITRAN database to obtain an extended database;

[0013] According to the extended gas spectral line parameters in the extended database, the atmospheric transmittance in the second target altitude range is calculated using MODTRAN software; the second target altitude range is less than or equal to 100 km;

[0014] The absorption cross sections of the molecular gas at different wavelengths within the first target height range are extracted from the extended database to obtain a second absorption cross section.

[0015] Optionally, determining the atmospheric transmittance within the first target height range using an atmospheric transmission function according to the mixed gas absorption coefficient includes:

[0016] Using the formula:

[0017] ;

[0018] determining atmospheric transmittance within a first target altitude range;

[0019] in, is the atmospheric transmittance, is the mixed gas absorption coefficient, is the wavelength, For the band, For height.

[0020] Optionally, determining the atomic gas absorption coefficient corresponding to each height includes:

[0021] Using the formula:

[0022] ;

[0023] Calculate the atomic gas absorption coefficient corresponding to each height;

[0024] in, For height The corresponding atomic gas absorption coefficient, is the number density of the ith atomic gas, is the absorption cross section of the ith atomic gas at different wavelengths, is the sum over all atomic gases.

[0025] Optionally, determining the molecular gas absorption coefficient corresponding to each height includes:

[0026] Using the formula:

[0027] ;

[0028] Calculate the molecular gas absorption coefficient corresponding to each height;

[0029] in, For height The corresponding molecular gas absorption coefficient, For the The number density of the gas molecules is For the The absorption cross section of a molecular gas at different wavelengths is is the sum over all molecular gases.

[0030] Optionally, the SCLB model is used to expand the gas spectral line parameters in the HITRAN database to obtain an expanded database including:

[0031] The gas spectral line parameters are processed by using an LSTM algorithm to obtain data features and memory data of the gas spectral line parameters;

[0032] According to the data features and the memory data, a physical constraint module is used to segment the gas spectral line parameters to obtain a plurality of data segments;

[0033] Genetic algorithm is used to perform crossover operation on multiple data segments in pairs to obtain the extended information between each data segment;

[0034] According to the extended information, a BP-Transformer algorithm is used to restore multiple data fragments to obtain extended gas spectral line parameters;

[0035] The extended gas spectral line parameters are stored to obtain an extended database.

[0036] Optionally, the calculating the atmospheric transmittance in the second target height range using MODTRAN software according to the extended gas line parameters in the extended database includes:

[0037] Converting the extended gas spectral line parameters into an absorption cross-section data file in a preset format;

[0038] According to the parameters of the absorption cross section data file, the molecular content of the atmosphere model in the MODTRAN software is adjusted and the wavelength range of the MODTRAN software is set;

[0039] The atmospheric transmission process in the second target height range is simulated based on the adjusted atmospheric model and wavelength range to obtain simulation results; the simulation results include atmospheric transmittance.

[0040] Compared with the prior art, the present invention provides a method for determining long-distance atmospheric transmission characteristics, comprising:

[0041] Acquire the atmospheric parameters within the first target altitude range; determine the atomic gas absorption coefficient and the molecular gas absorption coefficient corresponding to each altitude based on the gas composition, number density, the first absorption cross section and the second absorption cross section; sum and calculate the atomic gas absorption coefficient and the molecular gas absorption coefficient to obtain the mixed gas absorption coefficient; and determine the atmospheric transmittance within the first target altitude range using the atmospheric transmission function according to the mixed gas absorption coefficient. The present invention achieves accurate simulation of the atmospheric transmission characteristics within the altitude range by acquiring data on the atmospheric components varying with altitude within an altitude range of more than 100 km and solving the atmospheric transmission equation, thereby significantly improving the accuracy and applicability of the calculation of atmospheric transmission characteristics in space-based detection.

[0042] In a second aspect, the present invention further provides a device for determining long-distance atmospheric transmission characteristics, comprising:

[0043] An atmospheric parameter acquisition module, used to acquire atmospheric parameters within a first target altitude range; the first target altitude range is greater than 100 km; the atmospheric parameters include gas components, number densities corresponding to each gas component, first absorption cross sections of atomic gas at different wavelengths, and second absorption cross sections of molecular gas at different wavelengths;

[0044] A gas absorption coefficient calculation module, used to determine the atomic gas absorption coefficient and the molecular gas absorption coefficient corresponding to each height based on the gas composition, number density, first absorption cross section and second absorption cross section;

[0045] A mixed gas absorption coefficient calculation module, used for summing up the atomic gas absorption coefficient and the molecular gas absorption coefficient to obtain the mixed gas absorption coefficient;

[0046] The atmospheric transmittance calculation module is used to determine the atmospheric transmittance within the first target height range according to the mixed gas absorption coefficient and using the atmospheric transmission function; the atmospheric transmittance is used to reflect the atmospheric transmission characteristics.

[0047] In a third aspect, the present invention provides a device for determining long-distance atmospheric transmission characteristics, comprising:

[0048] A communication unit / communication interface, used to obtain atmospheric parameters within a first target altitude range; the first target altitude range is greater than 100 km; the atmospheric parameters include gas components, number densities corresponding to each gas component, first absorption cross sections of atomic gas at different wavelengths, and second absorption cross sections of molecular gas at different wavelengths;

[0049] A processing unit / processor, configured to determine an atomic gas absorption coefficient and a molecular gas absorption coefficient corresponding to each height based on the gas composition, the number density, the first absorption cross section, and the second absorption cross section;

[0050] The atomic gas absorption coefficient and the molecular gas absorption coefficient are summed and calculated to obtain a mixed gas absorption coefficient;

[0051] According to the mixed gas absorption coefficient, an atmospheric transmission function is used to determine the atmospheric transmittance within a first target height range; the atmospheric transmittance is used to reflect the atmospheric transmission characteristics.

[0052] In a fourth aspect, the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores instructions, and when the instructions are executed, the method for determining long-distance atmospheric transmission characteristics is implemented.

[0053] Compared with the prior art, the beneficial effects of the second aspect device type solution, the third aspect equipment type solution, and the fourth aspect computer-readable storage medium type solution provided by the present invention are the same as the beneficial effects of the double-sided printing method described in the above technical solutions, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0055] Figure 1 A flow chart of a method for determining long-distance atmospheric transmission characteristics provided by the present invention;

[0056] Figure 2 The atmospheric transmittance calculation process diagram for the range of 100-500km provided by the present invention;

[0057] Figure 3 A comparison chart of the atmospheric transmittance calculated by the method of the present invention and the atmospheric transmittance calculated by MODTRAN software within a range of 40-60 km provided by the present invention;

[0058] Figure 4 A comparison chart of the atmospheric transmittance calculated by the method of the present invention and the atmospheric transmittance calculated by MODTRAN software within a range of 60-100 km provided by the present invention;

[0059] Figure 5 The calculation results of the atmospheric transmittance of 40-400km provided by the present invention;

[0060] Figure 6 The calculation results of 60-400km atmospheric transmittance provided by the present invention;

[0061] Figure 7 A schematic diagram of the structure of a device for determining long-distance atmospheric transmission characteristics provided by the present invention;

[0062] Figure 8 A schematic diagram of the structure of a device for determining long-distance atmospheric transmission characteristics provided by the present invention. DETAILED DESCRIPTION

[0063] In order to clearly describe the technical solutions of the embodiments of the present invention, in the embodiments of the present invention, words such as "first" and "second" are used to distinguish the same items or similar items with basically the same functions and effects. For example, the first threshold and the second threshold are only used to distinguish different thresholds, and their order is not limited. Those skilled in the art can understand that words such as "first" and "second" do not limit the quantity and execution order, and words such as "first" and "second" do not necessarily limit them to be different.

[0064] It should be noted that, in the present invention, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the present invention should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0065] In the present invention, "at least one" means one or more, and "plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the objects associated before and after are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b or c can mean: a, b, c, the combination of a and b, the combination of a and c, the combination of b and c, or the combination of a, b and c, where a, b, c can be single or multiple.

[0066] Before introducing the embodiments of the present invention, the following definitions are given for the relevant terms involved in the embodiments of the present invention:

[0067] SABER is an important detection instrument on the TIMED satellite. SABER satellite data is mainly used to detect parameters such as temperature, pressure and composition in the atmosphere.

[0068] The NRLMISSE model is mainly used to simulate and predict key parameters such as atmospheric temperature, gas composition and gas density within the range of 100-500km above sea level. Through the long-term memory mechanism, NRLMISSE can capture the long-term dependencies in atmospheric changes, and effectively handle the complex nonlinear relationship between altitude and atmospheric physical properties through structured embedding. The model can accurately reflect the changing trends of atmospheric parameters at different altitudes without the need for explicit relationship diagrams, thus providing accurate prediction and analysis tools for scientific research and applications of the upper atmosphere.

[0069] The absorption cross section refers to the ratio of the number of particles passing through a unit volume in a certain direction per unit time to the number of particles passing through the same unit volume per unit time. It reflects the probability of particles being absorbed during the propagation of a substance. The larger the absorption cross section, the higher the probability of particles being absorbed in the substance.

[0070] MODTRAN (Moderate Resolution Atmospheric Transmission) is a widely used atmospheric transmission modeling tool. It uses the radiation transfer equation to calculate the absorption and radiation characteristics of gases in the atmosphere by calling the gas absorption spectrum data in the HITRAN (High-resolution Transmission Molecular Absorption Database) database. The implementation of MODTRAN relies on the gas molecule absorption spectrum information provided by the HITRAN database, and uses preprocessing tools to convert the line list data in the HITRAN database into an absorption cross-section data file suitable for MODTRAN calculations. Subsequently, the calculation parameters are specified through the input file for radiation transmission calculations. This technical solution can achieve refined calculations by replacing or updating the HITRAN database, which is suitable for atmospheric transmission research and practical application scenarios.

[0071] However, MODTRAN can only calculate atmospheric transmission characteristics below 100 km and cannot meet the needs of space-based detection.

[0072] In order to solve the above problems, the present invention provides a method, device, equipment and medium for determining long-distance atmospheric transmission characteristics, which will be described below with reference to the accompanying drawings.

[0073] See also Figure 1 The present invention provides a method for determining long-distance atmospheric transmission characteristics, comprising the following steps:

[0074] Step 101: Acquire atmospheric parameters within a first target altitude range;

[0075] The first target altitude range is greater than 100km; atmospheric parameters include gas components, number density corresponding to each gas component, first absorption cross section of atomic gas at different wavelengths, and second absorption cross section of molecular gas at different wavelengths; atmospheric components and number density are data that vary with altitude, and both are calculated using SABER satellite data and the NRLMISSE model; the first absorption cross section of atomic gas at different wavelengths is queried through the NIST database. The second absorption cross section of molecular gas at different wavelengths is obtained from the expanded HITRAN database.

[0076] Exemplarily, the gas components in the range of 100-500 km mainly include:

[0077] Atomic gas: oxygen atoms (O), nitrogen atoms (N), hydrogen atoms (H); molecular gas: oxygen molecules (O2), nitrogen molecules (N2); other small components: helium atoms (He) and small trace gases.

[0078] Step 102: determining the atomic gas absorption coefficient and the molecular gas absorption coefficient corresponding to each height based on the gas composition, number density, first absorption cross section and second absorption cross section;

[0079] Specifically, the atomic gas absorption coefficient is determined according to the gas composition, number density and the first absorption cross section; the molecular gas absorption coefficient corresponding to each height is determined according to the gas composition, number density and the second absorption cross section.

[0080] As an alternative, in the range of 100-500km, the main atomic gases include oxygen atoms, nitrogen atoms and hydrogen atoms. The concentration of these atomic gases varies with altitude. Determining the atomic gas absorption coefficient includes:

[0081] Using formula (1):

[0082] (1)

[0083] Calculate the atomic gas absorption coefficient corresponding to each height;

[0084] in, For height The corresponding atomic gas absorption coefficient, is the number density of the ith atomic gas, is the absorption cross section of the ith atomic gas at different wavelengths, To sum over all atomic gases, is the wavelength.

[0085] As an optional method, within the range of 100-500 km, the main molecules include oxygen molecules and nitrogen molecules, and their concentrations vary with altitude. Determining the molecular gas absorption coefficient corresponding to each altitude includes: using formula (2):

[0086] (2)

[0087] Calculate the molecular gas absorption coefficient corresponding to each height;

[0088] in, For height The corresponding molecular gas absorption coefficient, For the The number density of the gas molecules is For the The absorption cross section of a molecular gas at different wavelengths is is the sum over all molecular gases.

[0089] Step 103: calculating and summing the atomic gas absorption coefficient and the molecular gas absorption coefficient to obtain a mixed gas absorption coefficient;

[0090] In the range of 100-500 km altitude, the mixed gas absorption coefficient is the sum of the atomic gas absorption coefficient and the molecular gas absorption coefficient; specifically, step 103 includes:

[0091] Using formula (3):

[0092] (3)

[0093] Calculate the absorption coefficient of the gas mixture.

[0094] in, is the absorption coefficient of the mixed gas.

[0095] Step 104: determining the atmospheric transmittance within a first target height range using an atmospheric transmission function according to the mixed gas absorption coefficient;

[0096] The atmospheric transmittance is used to reflect the atmospheric transmission characteristics.

[0097] Specifically, use formula (4):

[0098] (4)

[0099] determining atmospheric transmittance within a first target altitude range;

[0100] in, is the atmospheric transmittance, is the mixed gas absorption coefficient, is the wavelength, For the band, For height.

[0101] The derivation process of formula (4) is as follows:

[0102] The atmospheric transmission equation is used to describe the propagation process of electromagnetic waves in the atmosphere, taking into account the effects of absorption, scattering and emission. The atmospheric transmission equation is shown in formula (5):

[0103] (5)

[0104] in, represents the radiation intensity of wavelength, is the atmospheric extinction coefficient, including absorption and scattering effects, is the radiative diffusion coefficient of the atmosphere.

[0105] In the upper atmosphere at 100-500 km, the environment is thin and mainly composed of atomic gas and a small amount of molecular gas. Therefore, the scattering effect can be ignored, that is, , only the absorption effect needs to be considered. At the same time, the radiation divergence effect of the atmosphere can also be ignored, that is, , so the above conditions are used to simplify formula (5) to obtain the simplified formula (6):

[0106] (6)

[0107] By converting formula (6), we can get the formula for the change of light intensity along the path within the altitude of 100-500km, as shown in formula (7):

[0108] (7)

[0109] in, Shows atmospheric transmittance.

[0110] pass Figure 1It can be seen from the method that the present invention combines the SABER satellite observation data with the NRLMISSE model calculation results to obtain the data of atmospheric components changing with altitude within the altitude range of more than 100km, and by solving the atmospheric transmission equation, the atmospheric transmittance calculation within the altitude range is realized, especially in the altitude range of 400-500km. Due to the thin atmosphere, the scattering effect can be ignored. The present invention accurately models and calculates the absorption effect, obtains the atmospheric transmittance data at a farther detection distance, fills the gap in the prior art in the calculation of atmospheric transmittance in high-altitude areas, not only improves the accuracy of atmospheric transmittance calculation, but also meets the needs of higher calculation range and more comprehensive data coverage. It solves the need for calculating atmospheric transmission characteristics under long-distance detection conditions when the space-based low-orbit observation platform is operating at high altitude. In addition, the second absorption cross section of molecular gases at different wavelengths is obtained from the expanded HITRAN database. The expanded HITRAN database is more refined than the traditional HITRAN database data, so the data of the second absorption cross section is more accurate, and then the calculation result of atmospheric transmittance is more accurate.

[0111] The traditional HITRAN database is the basis for MODTRAN to calculate atmospheric transmission characteristics. However, some of its gas spectral line parameters are missing data. The results obtained by using these parameters to calculate within the required range are inaccurate or even impossible, which makes the MODTRAN calculation results inaccurate.

[0112] In view of this, the present invention expands the HITRAN database. Based on the expanded HITRAN database, the calculation result of the atmospheric transmittance below 100 km can be made more accurate. When calculating the atmospheric transmittance above 100 km, the second absorption cross section is obtained from the expanded HITRAN database. Therefore, before obtaining the atmospheric parameters within the first target altitude range, the HITRAN database needs to be expanded, specifically including:

[0113] Step S1: Obtain the HITRAN database;

[0114] The HITRAN database includes gas spectral line parameters, which include wave number, absorption intensity, broadening coefficient and other data.

[0115] Step S2: using the SCLB model to expand the gas spectral line parameters in the HITRAN database to obtain an expanded database;

[0116] The SCLB model includes a data distribution quantification module and a data distribution matching module. In the data distribution quantification module, the model divides the gas spectral line parameters into multiple segments with significant distribution differences through the improved LSTM algorithm, and generates extended information through genetic algorithm crossover operation. The attention mechanism helps LSTM better capture the distribution characteristics of the data by introducing physical constraints. In the data distribution matching module, the distribution segments are restored through the improved BP-Transformer algorithm, and a prediction model with strong generalization ability is constructed by learning the distribution laws and common characteristics between different segments. At the same time, the data distribution matching module introduces a regularization constraint mechanism in the loss function to improve the accuracy of gas spectral line parameter prediction. In the prediction process, the SCLB model adopts a single-step cycle prediction method to gradually predict the parameters of the data segment closest to the known data, and iterates the prediction results as new training data until the expansion of all gas spectral line parameters is completed. This method not only greatly reduces the computational cost, but also effectively improves the accuracy and applicability of the prediction results.

[0117] The SCLB model can accurately expand the spectral parameters of unknown and missing spectral segments, solving the problem of inaccurate calculation results in the case of missing parameters in the prior art.

[0118] Step S3: Calculating the atmospheric transmittance in the second target height range using MODTRAN software according to the extended gas line parameters in the extended database;

[0119] Wherein, the second target altitude range is less than or equal to 100 km;

[0120] Specifically, first, the extended gas spectral line parameters are converted into an absorption cross-section data file in a preset format;

[0121] Then, adjusting the molecular content of the atmosphere model in the MODTRAN software according to the parameters of the absorption cross section data file and setting the wavelength range of the MODTRAN software;

[0122] Finally, the atmospheric transmission process in the second target height range is simulated based on the adjusted atmospheric model and wavelength range to obtain simulation results; the simulation results include atmospheric transmittance.

[0123] The expanded HITRAN database can be used to more accurately describe the characteristics of gas spectral line parameters changing with conditions. By calling the expanded database and combining it with the MODTRAN software, a more accurate calculation of atmospheric transmittance within a specific altitude range can be achieved under specific atmospheric modes and observation conditions. Compared with the original database, the expanded database significantly improves the accuracy and applicability of atmospheric transmittance calculations.

[0124] Step S4: extracting absorption cross sections of molecular gas within the first target height range at different wavelengths from the extended database to obtain a second absorption cross section.

[0125] Specifically, the above step S2 can be implemented based on the following steps:

[0126] Step S21: using the LSTM algorithm to process the gas spectral line parameters to obtain data features and memory data of the gas spectral line parameters;

[0127] The LSTM algorithm uses forget gate, input gate, memory gate and output gate to obtain data features, and the memory gate obtains memory data. The previous unit state data is combined with the memory gate and forget gate calculation results of the current cell to obtain the data state of the current cell. Among them, the gas spectral line parameters corresponding to each wave value are taken as a cell.

[0128] Step S22: segmenting the gas spectral line parameters according to the data features and the memory data using a physical constraint module to obtain a plurality of data segments;

[0129] The distribution characteristics of each data segment vary significantly.

[0130] The physical constraint module is established based on the physical characteristics of gas spectral radiation. The existence of the physical constraint module can establish the association between the output of the current unit and the information stored in the past cells. The physical constraint module inherits the network data through the fully connected layer and uses the physical formula of high-temperature gas spectral radiation as a convergence constraint to perform network training. The physical formula constraints of the physical constraint module can allow the model to better extract the data characteristics of gas spectral line parameters in different wavenumber bands.

[0131] Step S23: using a genetic algorithm to perform a crossover operation on the multiple data segments in pairs to obtain extended information between the data segments;

[0132] Step S24: according to the extended information, the BP-Transformer algorithm is used to restore the multiple data fragments to obtain extended gas spectral line parameters;

[0133] The BP-Transformer algorithm uses a binary search mechanism to determine whether there is a link relationship between data segments, and then restores the entire gas spectral line parameter data. By comparing the restored data with the gas spectral line parameters in the prior HITRAN database, the loss function is trained, and then the training of the entire model is completed, making the model prediction results more accurate; further, the BP-Transformer algorithm can be improved. The loss function of the improved BP-Transformer algorithm adds a regular optimization term composed of the physical characteristics of gas spectral radiation, which can effectively improve the accuracy of the model.

[0134] The extended gas spectral line parameters are stored to obtain an extended HITRAN database, namely, an extended database.

[0135] As an optional method, when there are missing gas spectral line parameters in the HITRAN database, the atmospheric transmittance data can be calculated by the following alternative method:

[0136] Based on the physical mechanism of gas radiation transmission, combined with the gas molecule internal energy level distribution model, collision broadening theory (such as Voigt line shape) and transition dipole moment calculation methods, numerical calculation methods are used to simulate the absorption characteristics of gas under different environmental conditions (temperature, pressure, concentration, etc.), thereby obtaining more precise atmospheric transmittance data and transmittance performance under long-distance detection. This method includes the following key steps:

[0137] Calculation and simulation of energy level distribution: Through quantum mechanics calculation or vibration-rotation energy level distribution model, the vibration and rotation energy level distribution of gas molecules is simulated, and its transition frequency is calculated to obtain the phase transition wavelength or wave number.

[0138] Transition parameter calculation: Combining the quantum transition selection rule with the dipole moment theory, the transition strength of each energy level is calculated while considering the effect of temperature on energy level occupancy, such as based on the Boltzmann distribution.

[0139] Broadening mechanism modeling and absorption parameter calculation: Taking into account factors such as natural broadening, collision broadening and Doppler broadening, the absorption cross-section parameters and broadening parameters are generated based on the Voigt linear function or other fitting methods to complete the gas absorption characteristics.

[0140] Atmospheric transmittance data generation: The transmittance characteristics of the atmosphere under specific conditions are calculated through the radiation transfer equation, and the atmospheric transmittance data of the segment absorption characteristics are output, which can be applied to detection conditions at a greater distance.

[0141] Through this method, the absorption characteristics can be completed within the missing parameters of HITRAN, thereby achieving detailed modeling of atmospheric transmittance and effectively improving the detection distance and sensitivity.

[0142] As an optional method, the relevant parameters of atmospheric transmittance can be directly obtained through experimental means to replace the missing data in the HITRAN database. The steps are as follows:

[0143] Construction of experimental equipment: Build an experimental device for measuring atmospheric transmittance, use high-precision light sources, detectors and auxiliary devices to control the environment (temperature, pressure, etc.), and measure the gas absorption characteristics under different conditions.

[0144] Measurement and fitting analysis: The absorption characteristics of the target gas are measured experimentally, and the absorption cross section, collision broadening parameters, etc. are extracted by combining the fitting method. The atmospheric transmittance data under the corresponding conditions are further obtained through radiation transmission calculation.

[0145] Completion and optimization: Combine the experimental transmittance data with existing databases, such as HITRAN, to complete the missing parameter data and ensure the completeness and accuracy of the transmittance calculation.

[0146] See also Figure 2 The present invention can realize the calculation of atmospheric transmittance within the altitude range of 100-500km. In the specific implementation, the atmospheric parameters of the atmospheric model are obtained, the observation conditions are configured, and the bands and band resolutions are observed. Below 100km, the SCLB model is first used to expand the HITRAN gas line parameters, and the gas line absorption coefficient is calculated according to the expanded HITRAN database, and the gas absorption, scattering, and radiation effects are simulated based on the radiation transmission equation to calculate the atmospheric transmittance below 100km. Within the range of 100-500km, the atmospheric parameters within the range of 100-500km are first obtained, the atmospheric transmission equation is established, the extinction coefficient is calculated, and the atmospheric transmittance is calculated based on the atmospheric transmission function.

[0147] See also Figure 3-Figure 6 , MODTRAN software can calculate the atmospheric transmission attenuation characteristics within the range of 0-120 km from the ground. Limited by the software capabilities, the atmospheric transmission attenuation calculation accuracy is relatively high within the range of 0 km-100 km, and the calculation accuracy is not high within the range of 100 km above the ground. The atmospheric transmittance calculated by the present invention is compared with the results calculated by MODTRAN software within the range of 100 km from the ground, as shown in FIG. Figure 3 and Figure 4 As shown in the figure, within the altitudes of 40-60km and 60-100km, the results calculated by the Transfer Calculation of the present invention have good consistency, and there are slight differences in the values ​​of some wave number bands. This is because the present invention uses the expanded HITRAN database to calculate the gas absorption characteristics, and can obtain more precise atmospheric transmittance calculation results. Figure 5 and Figure 6 As shown, the atmospheric transmittance calculated by the present invention at an altitude of 40-400 km and an altitude of 60-400 km, at the same altitude, the attenuation of the atmospheric transmittance decreases with the increase of the altitude.

[0148] The embodiment of the present invention can divide the functional modules according to the above method example. For example, each functional module can be divided according to each function, or two or more functions can be integrated into one processing module. The above integrated module can be implemented in the form of hardware or in the form of software functional modules. It should be noted that the division of modules in the embodiment of the present invention is schematic and is only a logical function division. There may be other division methods in actual implementation.

[0149] In the case of dividing each functional module into corresponding functional modules, Figure 7 FIG. 2 shows a schematic diagram of the structure of a device for determining long-distance atmospheric transmission characteristics provided by the present invention. Figure 7 As shown, the device comprises:

[0150] An atmospheric parameter acquisition module 701 is used to acquire atmospheric parameters within a first target altitude range; the first target altitude range is greater than 100 km; the atmospheric parameters include gas components, number densities corresponding to each gas component, first absorption cross sections of atomic gas at different wavelengths, and second absorption cross sections of molecular gas at different wavelengths;

[0151] A gas absorption coefficient calculation module 702, for determining the atomic gas absorption coefficient and the molecular gas absorption coefficient corresponding to each height based on the gas composition, number density, first absorption cross section and second absorption cross section;

[0152] A mixed gas absorption coefficient calculation module 703 is used to calculate the sum of the atomic gas absorption coefficient and the molecular gas absorption coefficient to obtain the mixed gas absorption coefficient;

[0153] The atmospheric transmittance calculation module 704 is used to determine the atmospheric transmittance within the first target height range according to the mixed gas absorption coefficient and using the atmospheric transmission function; the atmospheric transmittance is used to reflect the atmospheric transmission characteristics.

[0154] Optionally, the device further includes a HITRAN database expansion and an atmospheric transmittance calculation module for a second target altitude range, which may specifically include:

[0155] A HITRAN database acquisition unit, used for acquiring a HITRAN database;

[0156] A SCLB model expansion unit, used for expanding the gas spectral line parameters in the HITRAN database using the SCLB model to obtain an expanded database;

[0157] A second target altitude range atmospheric transmittance calculation unit, used to calculate the atmospheric transmittance of the second target altitude range using MODTRAN software according to the extended gas line parameters in the extended database; the second target altitude range is less than or equal to 100 km;

[0158] The second absorption cross section acquisition unit is used to extract the absorption cross sections of the molecular gas within the first target height range at different wavelengths from the extended database to obtain the second absorption cross section.

[0159] Optionally, the gas absorption coefficient calculation module 702 may include an atomic gas absorption coefficient calculation unit and a molecular gas absorption coefficient calculation unit;

[0160] The atomic gas absorption coefficient calculation unit is used to adopt the formula:

[0161] ;

[0162] Calculate the atomic gas absorption coefficient corresponding to each height;

[0163] in, For height The corresponding atomic gas absorption coefficient, is the number density of the ith atomic gas, is the absorption cross section of the ith atomic gas at different wavelengths, is the sum over all atomic gases.

[0164] The molecular gas absorption coefficient calculation unit is used to adopt the formula:

[0165] ;

[0166] Calculate the molecular gas absorption coefficient corresponding to each height;

[0167] in, For height The corresponding molecular gas absorption coefficient, For the The number density of the gas molecules is For the The absorption cross section of a molecular gas at different wavelengths is is the sum over all molecular gases.

[0168] Optionally, the atmospheric transmittance calculation module 704 may be specifically used for:

[0169] Using the formula:

[0170] ;

[0171] determining atmospheric transmittance within a first target altitude range;

[0172] in, is the atmospheric transmittance, is the mixed gas absorption coefficient, is the wavelength, For the band, For height.

[0173] Optionally, the SCLB model extension unit may be used to:

[0174] The gas spectral line parameters are processed by using an LSTM algorithm to obtain data features and memory data of the gas spectral line parameters;

[0175] According to the data features and the memory data, a physical constraint module is used to segment the gas spectral line parameters to obtain a plurality of data segments;

[0176] Genetic algorithm is used to perform crossover operation on multiple data segments in pairs to obtain the extended information between each data segment;

[0177] According to the extended information, a BP-Transformer algorithm is used to restore multiple data fragments to obtain extended gas spectral line parameters;

[0178] The extended gas spectral line parameters are stored to obtain an extended database.

[0179] Optionally, the second target altitude range atmospheric transmittance calculation unit may be used to:

[0180] Converting the extended gas spectral line parameters into an absorption cross-section data file in a preset format;

[0181] According to the parameters of the absorption cross section data file, the molecular content of the atmosphere model in the MODTRAN software is adjusted and the wavelength range of the MODTRAN software is set;

[0182] The atmospheric transmission process in the second target height range is simulated based on the adjusted atmospheric model and wavelength range to obtain simulation results; the simulation results include atmospheric transmittance.

[0183] The above mainly introduces the solution provided by the embodiment of the present invention from the perspective of the interaction between various modules. It can be understood that in order to realize the above functions, it includes hardware structures and / or software modules corresponding to the execution of various functions. It should be easily appreciated by those skilled in the art that, in combination with the units and algorithm steps of each example described in the embodiments disclosed herein, the present invention can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present invention.

[0184] In the case of using the corresponding integrated unit, Figure 8 FIG. 2 is a schematic diagram showing the structure of a device for determining long-distance atmospheric transmission characteristics provided by the present invention. Figure 8 As shown, the device includes:

[0185] A communication unit / communication interface, used to obtain atmospheric parameters within a first target altitude range; the first target altitude range is greater than 100 km; the atmospheric parameters include gas components, number densities corresponding to each gas component, first absorption cross sections of atomic gas at different wavelengths, and second absorption cross sections of molecular gas at different wavelengths;

[0186] A processing unit / processor, configured to determine an atomic gas absorption coefficient and a molecular gas absorption coefficient corresponding to each height based on the gas composition, the number density, the first absorption cross section, and the second absorption cross section;

[0187] The atomic gas absorption coefficient and the molecular gas absorption coefficient are summed and calculated to obtain a mixed gas absorption coefficient;

[0188] According to the mixed gas absorption coefficient, an atmospheric transmission function is used to determine the atmospheric transmittance within a first target height range; the atmospheric transmittance is used to reflect the atmospheric transmission characteristics.

[0189] Among them, the processing unit can be a processor or a controller, for example, a central processing unit (CPU), a general processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. It can implement or execute various exemplary logic boxes, modules and circuits described in conjunction with the disclosure of the present invention. The processor can also be a combination that implements a computing function, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, and the like. The communication module can be a transceiver, a transceiver circuit or a communication interface, and the like. The storage module can be a memory.

[0190] like Figure 8 As shown, the processor may be a general-purpose central processing unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits for controlling the execution of the program of the present invention. The communication interface may be one or more. The communication interface may use any transceiver or other device for communicating with other devices or communication networks.

[0191] like Figure 8 As shown, the terminal device may further include a communication line. The communication line may include a path to transmit information between the components.

[0192] Optional, such as Figure 8 As shown, the terminal device may further include a memory. The memory is used to store computer-executable instructions for executing the solution of the present invention, and the execution is controlled by the processor. The processor is used to execute the computer-executable instructions stored in the memory, thereby implementing the method provided by the embodiment of the present invention.

[0193] like Figure 8As shown, the memory may be a read-only memory (ROM) or other types of static storage devices that can store static information and instructions, a random access memory (RAM) or other types of dynamic storage devices that can store information and instructions, or an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical disc, laser disc, optical disc, digital versatile disc, Blu-ray disc, etc.), a magnetic disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. The memory may exist independently and be connected to the processor through a communication line. The memory may also be integrated with the processor.

[0194] Optionally, the computer-executable instructions in the embodiment of the present invention may also be referred to as application program codes, which is not specifically limited in the embodiment of the present invention.

[0195] In a specific implementation, as an example, Figure 8 As shown, the processor may include one or more CPUs, such as Figure 8 CPU0 and CPU1 in.

[0196] In a specific implementation, as an example, Figure 8 As shown, the terminal device may include multiple processors, such as Figure 8 Each of these processors can be a single-core processor or a multi-core processor.

[0197] On the one hand, a computer-readable storage medium is provided, in which instructions are stored. When the instructions are executed, the above-mentioned method for determining long-distance atmospheric transmission characteristics is implemented.

[0198] In the above embodiments, all or part of the embodiments may be implemented by software, hardware, firmware or any combination thereof. When implemented by software, all or part of the embodiments may be implemented in the form of a computer program product. The computer program product includes one or more computer programs or instructions. When the computer program or instruction is loaded and executed on a computer, the process or function described in the embodiment of the present invention is executed in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, a terminal, a user device or other programmable device. The computer program or instruction may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer program or instruction may be transmitted from one website, computer, server or data center to another website, computer, server or data center by wired or wireless means. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available medium may be a magnetic medium, such as a floppy disk, a hard disk, or a tape; it may also be an optical medium, such as a digital video disc (DVD); it may also be a semiconductor medium, such as a solid state drive (SSD).

[0199] Although the present invention is described herein in conjunction with various embodiments, in the process of implementing the claimed invention, those skilled in the art may understand and implement other variations of the disclosed embodiments by viewing the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other components or steps, and "one" or "an" does not exclude multiple situations. A single processor or other unit may implement several functions listed in a claim. Certain measures are recorded in different dependent claims, but this does not mean that these measures cannot be combined to produce good results.

[0200] Although the present invention has been described in conjunction with specific features and embodiments thereof, it is apparent that various modifications and combinations may be made thereto without departing from the spirit and scope of the present invention. Accordingly, this specification and the accompanying drawings are merely exemplary illustrations of the present invention as defined by the appended claims and are deemed to cover any and all modifications, variations, combinations or equivalents within the scope of the present invention. Obviously, those skilled in the art may make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, the present invention is intended to include such modifications and variations if they fall within the scope of the claims of the present invention and their equivalents.

Claims

1. A method for determining long-distance atmospheric transmission characteristics, characterized in that: include: Get the HITRAN database; The SCLB model is used to expand the gas spectral line parameters in the HITRAN database to obtain an extended database; Extracting absorption cross sections of molecular gas at different wavelengths within a first target height range from the extended database to obtain a second absorption cross section; Acquire atmospheric parameters within a first target altitude range; the first target altitude range is greater than 100 km; the atmospheric parameters include gas components, number densities corresponding to each gas component, first absorption cross sections of atomic gas at different wavelengths, and second absorption cross sections of molecular gas at different wavelengths; Determine the atomic gas absorption coefficient and the molecular gas absorption coefficient corresponding to each height based on the gas composition, number density, first absorption cross section and second absorption cross section; The atomic gas absorption coefficient and the molecular gas absorption coefficient are summed and calculated to obtain a mixed gas absorption coefficient; According to the mixed gas absorption coefficient, an atmospheric transmission function is used to determine the atmospheric transmittance within a first target height range; the atmospheric transmittance is used to reflect the atmospheric transmission characteristics.

2. The method for determining long-distance atmospheric transmission characteristics according to claim 1, characterized in that: Before acquiring the atmospheric parameters within the first target altitude range, the method further includes: According to the extended gas spectral line parameters in the extended database, the atmospheric transmittance in the second target altitude range is calculated using MODTRAN software; the second target altitude range is less than or equal to 100 km.

3. The method for determining long-distance atmospheric transmission characteristics according to claim 1, characterized in that: Determining the atomic gas absorption coefficients for each height includes: Using the formula: ； Calculate the atomic gas absorption coefficient corresponding to each height; in, For height The corresponding atomic gas absorption coefficient, is the number density of the ith atomic gas, is the absorption cross section of the ith atomic gas at different wavelengths, To sum over all atomic gases, is the wavelength.

4. The method for determining long-distance atmospheric transmission characteristics according to claim 3, characterized in that: Determining the molecular gas absorption coefficients for each height includes: Using the formula: ； Calculate the molecular gas absorption coefficient corresponding to each height; in, For height The corresponding molecular gas absorption coefficient, For the The number density of the gas molecules is For the The absorption cross section of a molecular gas at different wavelengths is is the sum over all molecular gases.

5. The method for determining long-distance atmospheric transmission characteristics according to claim 2, characterized in that: The SCLB model is used to expand the gas spectral line parameters in the HITRAN database to obtain an expanded database including: The gas spectral line parameters are processed by using an LSTM algorithm to obtain data features and memory data of the gas spectral line parameters; According to the data features and the memory data, a physical constraint module is used to segment the gas spectral line parameters to obtain a plurality of data segments; Genetic algorithm is used to perform crossover operation on multiple data segments in pairs to obtain the extended information between each data segment; According to the extended information, a BP-Transformer algorithm is used to restore multiple data fragments to obtain extended gas spectral line parameters; The extended gas spectral line parameters are stored to obtain an extended database.

6. The method for determining long-distance atmospheric transmission characteristics according to claim 5, characterized in that: The step of calculating the atmospheric transmittance of the second target height range using MODTRAN software according to the extended gas line parameters in the extended database comprises: Converting the extended gas spectral line parameters into an absorption cross-section data file in a preset format; According to the parameters of the absorption cross section data file, the molecular content of the atmosphere model in the MODTRAN software is adjusted and the wavelength range of the MODTRAN software is set; The atmospheric transmission process in the second target height range is simulated based on the adjusted atmospheric model and wavelength range to obtain simulation results; the simulation results include atmospheric transmittance.

7. A device for determining long-distance atmospheric transmission characteristics, characterized in that: include: A HITRAN database acquisition unit, used for acquiring a HITRAN database; A SCLB model expansion unit, used for expanding the gas spectral line parameters in the HITRAN database using the SCLB model to obtain an expanded database; A second absorption cross section acquisition unit is used to extract the absorption cross sections of the molecular gas within the first target height range at different wavelengths from the extended database to obtain a second absorption cross section; An atmospheric parameter acquisition module, used to acquire atmospheric parameters within a first target altitude range; the first target altitude range is greater than 100 km; the atmospheric parameters include gas components, number densities corresponding to each gas component, first absorption cross sections of atomic gas at different wavelengths, and second absorption cross sections of molecular gas at different wavelengths; A gas absorption coefficient calculation module, used to determine the atomic gas absorption coefficient and the molecular gas absorption coefficient corresponding to each height based on the gas composition, number density, first absorption cross section and second absorption cross section; A mixed gas absorption coefficient calculation module, used for summing up the atomic gas absorption coefficient and the molecular gas absorption coefficient to obtain the mixed gas absorption coefficient; The atmospheric transmittance calculation module is used to determine the atmospheric transmittance within the first target height range according to the mixed gas absorption coefficient and using the atmospheric transmission function; the atmospheric transmittance is used to reflect the atmospheric transmission characteristics.

8. A device for determining long-distance atmospheric transmission characteristics, characterized in that: include: A communication unit or communication interface, used to obtain a HITRAN database; expand the gas spectral line parameters in the HITRAN database using the SCLB model to obtain an extended database; extract the absorption cross sections of molecular gases at different wavelengths within a first target altitude range from the extended database to obtain a second absorption cross section; obtain atmospheric parameters within the first target altitude range; the first target altitude range is greater than 100 km; the atmospheric parameters include gas components, number densities corresponding to each gas component, first absorption cross sections of atomic gases at different wavelengths, and second absorption cross sections of molecular gases at different wavelengths; A processing unit or processor determines the atomic gas absorption coefficient and the molecular gas absorption coefficient corresponding to each height based on the gas composition, number density, first absorption cross section and second absorption cross section; sums and calculates the atomic gas absorption coefficient and the molecular gas absorption coefficient to obtain a mixed gas absorption coefficient; and determines the atmospheric transmittance within a first target height range using an atmospheric transmission function according to the mixed gas absorption coefficient; the atmospheric transmittance is used to reflect the atmospheric transmission characteristics.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores instructions, and when the instructions are executed, the method for determining long-distance atmospheric transmission characteristics according to any one of claims 1 to 6 is implemented.

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