Particle backscattering coefficient acquisition method and device, storage medium and terminal

Abstract

The application provides a particle backscattering coefficient acquisition method and device, a storage medium and a terminal, wherein the method comprises the following steps: acquiring wide-angle VSF data of a target sea area, and acquiring corresponding backscattering full-angle volume scattering function data of the wide-angle VSF data by using an interpolation algorithm; acquiring corresponding backscattering distribution curves based on the backscattering full-angle volume scattering function data; extracting a plurality of corresponding angle values from a first interval, a second interval, a third interval and a fourth interval at a preset interval respectively, and arranging and combining all the angle values to acquire a plurality of different preset angle combinations; performing polynomial fitting based on each preset angle combination to acquire an estimated backscattering coefficient fitting model corresponding to the backscattering distribution curves; and inputting the backscattering full-angle volume scattering function data into the estimated backscattering coefficient fitting model for calculation to acquire a particle backscattering coefficient result. The application can improve the accuracy of acquiring the particle backscattering coefficient.

Description

Technical Field

[0001] This invention belongs to the field of marine optical technology and relates to a method for obtaining the particle backscattering coefficient, particularly to a method and apparatus for obtaining the particle backscattering coefficient, a storage medium and a terminal. Background Technology

[0002] Particle backscattering coefficient is a core parameter in marine optics for studying marine ecology and biogeochemistry.

[0003] In existing technologies, methods for measuring the backscattering coefficient of particles mainly rely on single-angle methods based on the conversion factor or in-situ measurements of the three-angle volume scattering function (VSF). However, the drawback of existing technologies lies in their reliance on conversion factors (χ²). p The single-angle method assumes χ p It is a fixed value that is unaffected by changes in region or wavelength, but χ p It is highly sensitive to changes in the shape of the scattering phase function; differences in particle size distribution and refractive index will affect the scattering phase function and χ². p The backscattering angle varies greatly. Commercial in-situ backscattering coefficient measurement devices using the single-angle method, such as BB3, BB9, and HydroScat-6, all use a single-angle volume scattering function measurement, compared to a fixed χ² value. p Multiplication to estimate the particle backscattering coefficient results in an error of nearly 15% in the single-angle method. Meanwhile, the three-angle method, which is currently used in the in-situ backscattering coefficient measurement modules of devices such as ECO-VSF and BGC-Argo for measuring VSFs up to 150 degrees, still has an error of more than 10% in estimating the backscattering coefficient. Summary of the Invention

[0004] The purpose of this invention is to provide a method, apparatus, storage medium, and terminal for obtaining the particle backscattering coefficient, which solves the technical problem of insufficient accuracy in obtaining the particle backscattering coefficient in the prior art.

[0005] In a first aspect, the present invention provides a method for obtaining the backscattering coefficient of particles, comprising:

[0006] Acquire wide-angle VSF data of the target sea area, and use an interpolation algorithm to obtain the backscattering function data of the wide-angle VSF data;

[0007] The corresponding backscattering distribution curve is obtained based on the backscattering function data of the backscattering full angle.

[0008] Multiple corresponding angle values ​​are extracted from the first interval, the second interval, the third interval, and the fourth interval at preset intervals, and all the angle values ​​are arranged and combined to obtain multiple different preset angle combinations;

[0009] Polynomial fitting is performed based on each of the preset angle combinations to obtain an estimated backscattering coefficient fitting model corresponding to the backscattering distribution curve;

[0010] The backscattering function data of the backscattering at all angles is input into the backscattering coefficient fitting model for calculation to obtain the particle backscattering coefficient result;

[0011] The preset angle combination includes a first angle, a second angle, a third angle, and a fourth angle. The first angle is any angle value extracted from the first interval, the second angle is any angle value extracted from the second interval, the third angle is any angle value extracted from the third interval, and the fourth angle is any angle value extracted from the fourth interval. The angle values ​​of the first interval, the second interval, the third interval, and the fourth interval increase sequentially, and the fourth interval is 150 degrees to 170 degrees.

[0012] In one embodiment of the present invention, performing polynomial fitting based on each of the preset angle combinations to obtain an estimated backscattering coefficient fitting model corresponding to the backscattering distribution curve includes:

[0013] Obtain the polynomial coefficient matrix corresponding to each preset angle combination to obtain multiple polynomial coefficient matrices;

[0014] Obtain the polynomial coefficient matrix with the smallest error between it and the backscattering distribution curve as the target polynomial coefficient matrix, and combine the target polynomial coefficient matrix and the corresponding preset angle combination as the fitting model for estimating the backscattering coefficient.

[0015] In one embodiment of the present invention, obtaining the polynomial coefficient matrix corresponding to a preset angle combination includes:

[0016]

[0017] Where a represents the polynomial coefficient matrix, θ n Represents the nth angle. This represents the backscattering distribution curve value.

[0018] In one embodiment of the present invention, it further includes:

[0019] The theoretical value of the particle backscattering coefficient is obtained by integrating the backscattering function data of the backscattering full angle in the rear hemisphere;

[0020] Obtain the absolute difference between the particle backscattering coefficient result and the theoretical value of the particle backscattering coefficient. If the absolute difference is greater than a preset threshold, reduce the preset interval and re-obtain the particle backscattering coefficient result; otherwise, output the particle backscattering coefficient result as the final result.

[0021] In one embodiment of the present invention,

[0022] The first interval is 90 degrees to 110 degrees, the second interval is 110 degrees to 130 degrees, and the third interval is 130 degrees to 150 degrees.

[0023] In one embodiment of the present invention,

[0024] The wide-angle VSF data includes VSF data with angle values ​​greater than 150 degrees obtained through the following methods:

[0025] The direct light is sequentially passed through the sample cell and the neutral density filter before being directed to the output prism to obtain the corresponding reflected light.

[0026] The reflected light is sequentially directed through the neutral density filter and the sample cell to the focusing window to obtain a measurement light beam with an angle greater than 150 degrees;

[0027] The light ray to be measured is measured using a PMT to obtain VSF data with an angle value greater than 150 degrees;

[0028] The neutral density filter and the exit prism are bonded together with Canada balsam.

[0029] In one embodiment of the present invention,

[0030] The preset angle combination also includes a fifth angle, which is any angle value extracted from 170 degrees to 180 degrees.

[0031] Secondly, the present invention also provides a device for obtaining the particle backscattering coefficient, characterized in that it comprises:

[0032] The data acquisition module is used to acquire wide-angle VSF data of the target sea area and use an interpolation algorithm to obtain the backscattering function data of the wide-angle VSF data.

[0033] The curve generation module is used to obtain the corresponding backscattering distribution curve based on the backscattering function data at all angles.

[0034] An angle combination module is used to extract multiple corresponding angle values ​​from the first interval, the second interval, the third interval and the fourth interval at preset intervals, and to arrange and combine all the angle values ​​to obtain multiple different preset angle combinations.

[0035] The model selection module is used to perform polynomial fitting based on each of the preset angle combinations to obtain an estimated backscattering coefficient fitting model corresponding to the backscattering distribution curve.

[0036] The backscattering estimation module is used to input the backscattering full-angle volume scattering function data into the backscattering coefficient estimation fitting model for calculation, so as to obtain the particle backscattering coefficient result;

[0037] The preset angle combination includes a first angle, a second angle, a third angle, and a fourth angle. The first angle is any angle value extracted from the first interval, the second angle is any angle value extracted from the second interval, the third angle is any angle value extracted from the third interval, and the fourth angle is any angle value extracted from the fourth interval. The angle values ​​of the first interval, the second interval, the third interval, and the fourth interval increase sequentially, and the fourth interval is 150 degrees to 170 degrees.

[0038] Thirdly, the present invention also provides a storage medium storing a computer program thereon, which, when executed by a processor, implements the particle backscattering coefficient acquisition method as described above.

[0039] Fourthly, the present invention also provides a terminal, including a processor and a memory, wherein the memory and the processor are communicatively connected;

[0040] The memory is used to store computer programs, and the processor is used to execute the computer programs stored in the memory so that the terminal performs the particle backscattering coefficient acquisition method as described above.

[0041] As described above, the particle backscattering coefficient acquisition method, apparatus, storage medium, and terminal of the present invention have the following beneficial effects:

[0042] This invention constructs a preset angle combination based on four different angles and obtains a fitting model for estimating the particle backscattering coefficient through polynomial fitting. The particle backscattering coefficient result is then obtained using this fitting model. This invention can capture the scattering characteristics of particles from multiple angles, improving the estimation accuracy of the particle backscattering coefficient to more than four times that of existing technologies, with an error as low as 3%, thus significantly improving the estimation accuracy of the particle backscattering coefficient. Attached Figure Description

[0043] Figure 1 Wide-angle VSF data and corresponding χ values ​​for multiple sea areas are shown. p Distribution diagram.

[0044] Figure 2 The χ values ​​for different particle types are shown. pA schematic diagram showing the distribution between 90° and 180°.

[0045] Figure 3 A schematic flowchart of the method for obtaining the particle backscattering coefficient according to an embodiment of the present invention is shown.

[0046] Figure 4 This diagram illustrates the method for obtaining VSF data with an angle value greater than 150 degrees in the particle backscattering coefficient acquisition method described in this embodiment of the invention.

[0047] Figure 5 The diagram illustrates the accuracy of the particle backscattering coefficient acquisition method described in this embodiment of the invention when applied to acquiring backscattering coefficients in different sea areas around the world.

[0048] Figure 6 The diagram shows the error stripes for estimating the backscattering coefficient of particles in different sea areas using the single-angle method.

[0049] Figure 7 This diagram illustrates a comparison of error bands between the particle backscattering coefficient acquisition method and the three-angle method described in this embodiment of the invention.

[0050] Figure 8 A schematic diagram of the particle backscattering coefficient acquisition device according to an embodiment of the present invention is shown.

[0051] Figure 9 A schematic diagram of the terminal according to an embodiment of the present invention is shown. Detailed Implementation

[0052] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.

[0053] The following will describe in detail the principles and implementation methods of the particle backscattering coefficient acquisition method, apparatus, storage medium and terminal of this embodiment, so that those skilled in the art can understand the particle backscattering coefficient acquisition method, apparatus, storage medium and terminal of this embodiment without creative effort.

[0054] Existing methods for obtaining particle backscattering coefficients, whether single-angle or three-angle methods, all suffer from high errors. To address these technical problems, this invention involves analyzing a large amount of data to identify improvement strategies.

[0055] Figure 1 Wide-angle VSF data and corresponding χ values ​​for multiple sea areas are shown. p Distribution diagram, for reference Figure 1 As shown, Figure 1 The first two graphs in the middle are based on wide-angle VSF data from the East my country Sea, the second two graphs are based on wide-angle VSF data from the South my country Sea, and the third two graphs are based on wide-angle VSF data from other sea areas worldwide. In these three rows, the left graphs (a, c, e) show the variation of wide-angle VSF data at different angles. It can be seen that at the same angle, VSF can vary by nearly three orders of magnitude, indicating that the above three types of VSF data are sufficient to cover various different water optical types globally. The right graphs (b, d, f) show the χ² values ​​calculated from the VSF data corresponding to the left graphs. p Regarding the backscattering distribution (90°-180°), based on b and d, it can be seen that the South China Sea and the East China Sea belong to different optical types of water bodies, with significant differences in particle size and shape. Comparing the scattering phase function and conversion factor shapes of the two different types of particles, it can be found that the difference in backscattering distribution will increase significantly after 150°; and based on (f), the χ values ​​of different sea areas... p The mean changes the least at 120°, but its variance is still relatively large. For 140°, both the mean and variance change significantly. Therefore, the above reasons lead to an increase in the estimation error of the single-angle backscattering coefficient.

[0056] This invention applies to different particle types χ p The distribution was further analyzed. Figure 2 The χ values ​​for different particle types are shown. p A schematic diagram showing the distribution between 90° and 180° is provided for reference. Figure 2 As shown, the two different types of particles after 150° χ p The difference gradually increases, and can exceed 40% at its maximum.

[0057] This invention analyzes the volume scattering function at all angles and finds differences after 150 degrees. Therefore, it adopts a unique four-angle method, that is, adding an angle after 150 degrees to construct a preset angle combination.

[0058] To address the aforementioned technical problems in the prior art, this invention provides a method for obtaining the particle backscattering coefficient.

[0059] Figure 3 A schematic flowchart of the method for obtaining the particle backscattering coefficient according to an embodiment of the present invention is shown. (Refer to...) Figure 3 As shown, the method for obtaining the particle backscattering coefficient in this embodiment of the invention mainly includes steps S100 to S500.

[0060] Step S100: Obtain wide-angle VSF data of the target sea area, and use an interpolation algorithm to obtain the backscattering function data of the wide-angle VSF data.

[0061] Wide-angle VSF (Volume Scattering Function) data refers to the volume scattering function values ​​at different angles, representing the distribution of light scattering intensity by particles per unit volume of water as a function of the scattering angle. Specifically, in step S100, a wide-angle volume scattering function measuring instrument is used to acquire wide-angle VSF data for the target sea area, which is the area where the particle backscattering coefficient is to be obtained. Based on the wide-angle VSF data, an interpolation algorithm is used to obtain complete backscattering function data for the entire backscattering angle (i.e., 90° to 180°). Optionally, the interpolation algorithm is implemented using the interp1 function in Matlab. The implementation process is as follows: the interp1 function is called, and linear interpolation is performed based on the measured data from 175° to 178.5° in the wide-angle VSF data to obtain the volume scattering function data for 180°. The wide-angle VSF data and the 180° volume scattering function data are combined to form the backscattering function data for the entire backscattering angle.

[0062] In existing technologies, the volume scattering function measurement beyond 150° suffers from interference from reflected light signals, resulting in a significant increase in the measurement signal and lower accuracy. Therefore, it is difficult to guarantee the estimation accuracy including the fourth angle and the accurate calculation of the particle backscattering coefficient. Optionally, Figure 4 This diagram illustrates the method for acquiring VSF data with an angle value greater than 150 degrees in the particle backscattering coefficient acquisition method described in this embodiment of the invention. Figure 4 The upper half is the main view of the acquisition process, and the lower half is the corresponding top view. (See reference) Figure 4 As shown, the method for obtaining VSF data with angle values ​​greater than 150 degrees in wide-angle VSF data includes the following steps:

[0063] Step S101: Direct light is sequentially passed through the sample cell and neutral density filter and directed toward the output prism to obtain the corresponding reflected light.

[0064] In this embodiment, the neutral density filter and the exit prism are bonded together with Canada balsam. The sample cell contains a suspended particulate sample from the target sea area to ensure that direct light passes through the analyte to measure the optical properties of the sample cell; the exit prism is used to change the direction of light propagation to generate corresponding reflected light; the neutral density filter is used to adjust the light intensity.

[0065] Step S102: The reflected light is sequentially directed through the neutral density filter and the sample cell to the focusing window to obtain a light beam with an angle greater than 150 degrees to be measured.

[0066] Step S102 passes the light through the sample cell again to enhance the interaction with the sample cell. Through multiple adjustments of the reflected light and interaction with the sample, the optical information of the light in the high-angle scattering region (i.e., the range greater than 150 degrees) is obtained. The focusing window is used to focus the reflected light to extract the light with an angle greater than 150 degrees as the light to be measured.

[0067] Step S103: Use a PMT to measure the light to be measured to obtain VSF data with an angle value greater than 150 degrees.

[0068] PMT, or photomultiplier tube, is used to measure the light beam to obtain VSF data with an angle greater than 150 degrees.

[0069] In summary, in steps S101-S103, after the direct light is incident on prism P2, it is reflected above the prism by the neutral density filter. Part of the reflected light returns to the sample cell via the prism, and the reflected light passes through the neutral density filter a second time, with energy approximately 10% of the original signal intensity. -6 The backscattered light beyond 150° is negligible. After being focused by a prism through a window, the backscattered light is measured by a PMT, which greatly reduces the influence of reflected light, effectively reducing the problem of backscattering overestimation, improving the acquisition quality of VSF data beyond 150°, and helping to improve the estimation accuracy of particle backscattering coefficient.

[0070] Step S200: Obtain the corresponding backscattering distribution curve based on the backscattering function data of the backscattering full angle.

[0071] Backscattering distribution curves are graphical representations used to illustrate the distribution of scattering intensity within a backscattering angle range. The backscattering distribution curve reflects the trend of backscattering intensity as a function of the scattering angle, and its height and range are related to particle size, density, optical properties, etc. Specifically, those skilled in the art can sample and plot the backscattering distribution curve based on backscattering full-angle volume scattering function data. In this embodiment of the invention, the backscattering distribution curve is the basis for subsequently obtaining a fitting model for estimating the backscattering coefficient.

[0072] Step S300: Extract multiple corresponding angle values ​​from the first interval, the second interval, the third interval and the fourth interval at preset intervals, and arrange and combine all angle values ​​to obtain multiple different preset angle combinations.

[0073] In this embodiment, the preset angle combination includes a first angle, a second angle, a third angle, and a fourth angle. The first angle is any angle value extracted from the first interval, the second angle is any angle value extracted from the second interval, the third angle is any angle value extracted from the third interval, and the fourth angle is any angle value extracted from the fourth interval, which is 150 degrees to 170 degrees. The angle values ​​of the first, second, third, and fourth intervals increase sequentially (first interval < second interval < third interval < fourth interval). That is, multiple corresponding angle values ​​are extracted from the first interval at preset intervals, multiple corresponding angle values ​​are extracted from the second interval at preset intervals, multiple corresponding angle values ​​are extracted from the third interval at preset intervals, and multiple corresponding angle values ​​are extracted from the fourth interval at preset intervals. Taking the first interval as [50, 100] and the preset interval as 5 as an example, the extracted multiple corresponding angle values ​​are {50, 55, 60, 65, ..., 95, 100}, each of which is a first angle. Similarly, the angle values ​​corresponding to the second, third, and fourth intervals can be obtained. The system collects all angle values ​​and arranges them according to the composition rules of preset angle combinations. Since there are four preset angle values: the first angle, the second angle, the third angle, and the fourth angle, different preset angle combinations can be obtained by arranging and combining all angle values. For example, if there are 10 angle values ​​corresponding to the first interval, 5 angle values ​​corresponding to the second interval, 5 angle values ​​corresponding to the third interval, and 5 angle values ​​corresponding to the fourth interval, then 10*5*5*5, or 1250 different preset angle combinations can be obtained based on all angle values.

[0074] Optionally, the first interval is 90 degrees to 110 degrees, the second interval is 110 degrees to 130 degrees, and the third interval is 130 degrees to 150 degrees. The interval settings in this embodiment can more accurately capture the distribution characteristics of backscattering, ensuring that sampling covers all key angular regions and avoiding the omission of important data. Depending on the actual situation, those skilled in the art can choose other suitable angle values ​​to construct the first to third intervals.

[0075] Optionally, the preset angle combination also includes a fifth angle, which is any angle value extracted from 170 to 180 degrees. By adding an angle value extracted from the fifth interval to the original preset angle combination, the introduction of the fifth angle provides more preset angle combinations for polynomial fitting, achieving sampling coverage of a larger backscattering angle range and improving the ability of the fitting model to express the backscattering distribution curve, thus reducing fitting errors. The improvement of this invention does not lie in simply adding more angles, but in adding a fourth angle of 150 degrees or more, which significantly improves accuracy. Those skilled in the art can use more angles; a five-angle approach is the most accurate, but compared to a four-angle approach, the accuracy of backscattering coefficient estimation is only improved by less than 1%, and the computational and measurement costs increase more significantly with increasing accuracy. Therefore, a four-angle approach is the optimal solution for combining accuracy and computational efficiency.

[0076] Step S400: Perform polynomial fitting based on each preset angle combination to obtain the estimated backscattering coefficient fitting model corresponding to the backscattering distribution curve.

[0077] Specifically, a polynomial fitting is performed on each preset angle combination to obtain the corresponding fitting result. Among all the fitting results, the one with the smallest error to the backscattering distribution curve is selected. This fitting result and its corresponding preset angle combination are then combined to form the backscattering coefficient estimation fitting model. The backscattering distribution curve describes the scattering intensity at different scattering angles and is crucial basic data for the fitting model. Step S400 involves performing polynomial fitting on preset angle combinations composed of four different angles. These angle values ​​are extracted from four intervals to ensure coverage of the key features of the distribution curve, thus obtaining the backscattering coefficient estimation fitting model corresponding to the backscattering distribution curve.

[0078] Optionally, performing polynomial fitting based on each preset angle combination to obtain the estimated backscattering coefficient fitting model corresponding to the backscattering distribution curve includes: obtaining the polynomial coefficient matrix corresponding to each preset angle combination to obtain multiple polynomial coefficient matrices; obtaining the polynomial coefficient matrix with the smallest error between it and the backscattering distribution curve as the target polynomial coefficient matrix; and combining the target polynomial coefficient matrix and the corresponding preset angle combination as the estimated backscattering coefficient fitting model.

[0079] Optionally, obtaining the polynomial coefficient matrix corresponding to the preset angle combination includes:

[0080]

[0081] Where a represents the polynomial coefficient matrix, θ n Represents the nth angle. This represents the backscattering distribution curve value. Specifically, in matrix A, θ n It is an angle value, θ n m Let m represent the angle raised to the power of m. The number of rows in matrix A is the number of angle values ​​n, corresponding to the number of angle values ​​from the preset angle combinations. The number of columns in matrix A is the order m of the fitting polynomial, which determines the complexity of the fitting process. That is, the fitting polynomial is:

[0082]

[0083] in, Let a denote a polynomial, and the corresponding polynomial coefficient matrix a is:

[0084] a = [a0, a1, ..., a m ] T

[0085] In this embodiment of the invention, a fitting model for the estimated backscattering coefficients corresponding to the backscattering distribution curve is obtained by fitting a polynomial coefficient matrix 'a'. T Let A represent the transpose of matrix A, (A T A)- 1 A represents T The inverse matrix of A is used to eliminate redundant constraints. Used to scatter the value vector φ p Mapping to a polynomial fitting space. Using the polynomial coefficient matrix in the above manner helps to speed up the fitting process. At the same time, the matrix contains the angle interval and the fitting order, which can meet the fitting requirements of different data distributions and can achieve high-precision approximation of complex backscattering distribution curves.

[0086] Step S500: Input the backscattering function data of the full-angle backscattering function into the backscattering coefficient fitting model for calculation to obtain the particle backscattering coefficient results.

[0087] The backscattering function data obtained in step S100 is input into the backscattering coefficient fitting model. The result calculated by the model is used as the particle backscattering coefficient result, which ensures that the particle backscattering coefficient result is highly matched with the real scattering characteristics and reduces the errors caused by insufficient angle sampling and uneven distribution.

[0088] Optionally, embodiments of the present invention further include verification and optimization of the particle backscattering coefficient results, specifically as described in steps S600-S700:

[0089] Step S600: Obtain the theoretical value of the corresponding particle backscattering coefficient by integrating the backscattering function data in the rear hemisphere.

[0090] Specifically, the theoretical value of the particle backscattering coefficient is obtained as follows:

[0091]

[0092] Where, β p (θ; λ) represents the backscattering function data across the entire angle (i.e., the measured volume scattering function value), β p (θ;λ)sinθ is the value of the backscattering distribution curve, defined as... Specifically That is, the values ​​between 90° and 180° in the backscattering distribution curve. Optionally, the theoretical value of the particle backscattering coefficient can be obtained by using the trapz function in Matlab, setting the fitting angle range to 90°~180°.

[0093] Step S700: Obtain the absolute difference between the particle backscattering coefficient result and the theoretical value of the particle backscattering coefficient. If the absolute difference is greater than the preset threshold, reduce the preset interval and re-obtain the particle backscattering coefficient result; otherwise, output the particle backscattering coefficient result as the final result.

[0094] Specifically, the absolute difference can be obtained using the following formula:

[0095]

[0096] Among them, b b b represents the result of the particle backscattering coefficient. b 理论 Δb represents the theoretical value of the particle backscattering coefficient. b This represents the absolute difference. If the absolute difference is less than a preset threshold, the particle backscattering coefficient result is directly output as the final result. If the absolute difference is greater than the preset threshold, the particle backscattering coefficient result is re-acquired after reducing the preset interval. Since the preset interval is the interval for extracting corresponding angles in the first, second, third, and fourth intervals, reducing the preset interval can increase the number of extracted angles and the number of preset angle combinations. This results in finer granularity for angle value extraction, which is beneficial for finding a better solution and thus improving the accuracy of obtaining the particle backscattering coefficient result.

[0097] To verify the technical effectiveness of the particle backscattering coefficient acquisition method of this invention, a comparative experiment was conducted based on the same dataset (wide-angle VSF data from the East my country Sea, the South my country Sea, and other global sea areas). The specific results are as follows:

[0098] Figure 5This diagram illustrates the accuracy of the particle backscattering coefficient acquisition method described in this embodiment of the invention when applied to acquiring backscattering coefficients in different sea areas worldwide. Figure 5 As shown, the first two graphs are experimental results based on wide-angle VSF data from the East my country Sea, the second two graphs are based on wide-angle VSF data from the South my country Sea, and the third two graphs are based on wide-angle VSF data from other sea areas worldwide. The first column shows the corresponding backscattering distribution curves; the second column shows the error in obtaining the particle backscattering coefficient using the existing three-angle method (three bars in the graph, i.e., three angles); and the third column shows the error in obtaining the particle backscattering coefficient using the method of this invention (four bars in the graph, i.e., four angles). Using a 5-degree preset interval as an example, this invention's method conducted experiments on different angle combinations, ultimately pinpointing four-angle combinations of 100°, 120°, 140°, and 160°. For each data set, the error was significantly lower than that of the three-angle method in the second column. Therefore, this invention's method greatly improves the accuracy of obtaining the particle backscattering coefficient.

[0099] Figure 6 This diagram illustrates the error bars used to estimate the backscattering coefficient of particles in different sea areas using the single-angle method. (Reference) Figure 6 The backscattering coefficient was estimated using the single-angle method with the 120° and 140° conversion factors most commonly used in existing technologies. The first column shows the results for 120° and the second column shows the results for 140°. The gray dashed line in the figure represents the 1:1 line, and the surrounding red bands represent the 5% error bands. It can be seen that the single-angle method will produce an error of nearly 15% (that is, the MAPD index in the figure). Figure 7 This diagram illustrates a comparison of error bands between the particle backscattering coefficient acquisition method described in this embodiment and the three-angle method. Experiments were conducted using three different rows of data in the diagram. The first column shows the results of the three-angle method, and the second column shows the results of the four-angle method forming a preset angle combination according to this invention. (Refer to...) Figure 7 As shown, the errors of this invention are all below 5%, and compared with the traditional three-angle method, this invention improves the estimation accuracy by more than 10%. Moreover, the four-angle method of this invention breaks the limitations of region and wavelength, and has high accuracy for backscattering estimation in different sea areas and at different wavelengths around the world.

[0100] The protection scope of the particle backscattering coefficient acquisition method of this embodiment is not limited to the execution order of the steps listed in this embodiment. Any solution implemented by adding, subtracting or replacing steps in the prior art based on the principle of this invention is included within the protection scope of this invention.

[0101] The particle backscattering coefficient acquisition method of this invention constructs a preset angle combination based on four different angles, obtains a fitting model for estimating the particle backscattering coefficient through polynomial fitting, and uses this fitting model to obtain the particle backscattering coefficient result, significantly improving the estimation accuracy of the particle backscattering coefficient. Simultaneously, by utilizing the method for acquiring VSF data with angle values ​​greater than 150 degrees in this invention, the acquisition quality of VSF data greater than 150 degrees can be improved, thereby further enhancing the estimation accuracy of the particle backscattering coefficient.

[0102] To address the aforementioned technical problems in the prior art, this invention also provides a device for obtaining the particle backscattering coefficient.

[0103] Figure 8 A schematic diagram of the particle backscattering coefficient acquisition device according to an embodiment of the present invention is shown. (Refer to...) Figure 8 As shown, the particle backscattering coefficient acquisition device of this embodiment includes:

[0104] The data acquisition module is used to acquire wide-angle VSF data of the target sea area and use an interpolation algorithm to obtain the backscattering function data of the wide-angle VSF data.

[0105] The curve generation module is used to obtain the corresponding backscattering distribution curve based on the backscattering function data at all angles.

[0106] An angle combination module is used to extract multiple corresponding angle values ​​from the first interval, the second interval, the third interval and the fourth interval at preset intervals, and to arrange and combine all the angle values ​​to obtain multiple different preset angle combinations.

[0107] The model selection module is used to perform polynomial fitting based on each of the preset angle combinations to obtain an estimated backscattering coefficient fitting model corresponding to the backscattering distribution curve.

[0108] The backscattering estimation module is used to input the backscattering full-angle volume scattering function data into the backscattering coefficient estimation fitting model for calculation, so as to obtain the particle backscattering coefficient result;

[0109] The preset angle combination includes a first angle, a second angle, a third angle, and a fourth angle. The first angle is any angle value extracted from the first interval, the second angle is any angle value extracted from the second interval, the third angle is any angle value extracted from the third interval, and the fourth angle is any angle value extracted from the fourth interval. The angle values ​​of the first interval, the second interval, the third interval, and the fourth interval increase sequentially, and the fourth interval is 150 degrees to 170 degrees.

[0110] The particle backscattering coefficient acquisition device of this invention constructs a preset angle combination based on four different angles, obtains an estimated particle backscattering coefficient fitting model through polynomial fitting, and obtains the particle backscattering coefficient result using the fitting model, which significantly improves the estimation accuracy of particle backscattering coefficient.

[0111] To address the aforementioned technical problems in the prior art, this embodiment of the invention also provides a storage medium storing a computer program, characterized in that the program, when executed by a processor, implements all the steps of the particle backscattering coefficient acquisition method of the embodiment.

[0112] The specific steps of the method for obtaining the particle backscattering coefficient and the beneficial effects obtained by applying the readable storage medium provided in the embodiments of the present invention are the same as those in the above embodiments, and will not be repeated here.

[0113] Those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing a processor. The program can be stored in a computer-readable storage medium, which is a non-transitory medium, such as random access memory, read-only memory, flash memory, hard disk, solid-state drive, magnetic tape, floppy disk, optical disk, and any combination thereof. The storage medium can be any available medium accessible to a computer or a data storage device such as a server or data center that integrates one or more available media. This available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., digital video disc (DVD)), or a semiconductor medium (e.g., solid-state drive (SSD)).

[0114] To address the aforementioned technical problems in the prior art, embodiments of the present invention also provide a terminal. Figure 9 A schematic diagram of the terminal structure according to an embodiment of the present invention is shown. (Refer to...) Figure 9 As shown, the terminal in this embodiment of the invention includes a processor and a memory, and the memory and the processor are communicatively connected; the memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory, so that the terminal performs all the steps of the particle backscattering coefficient acquisition method of the above embodiment.

[0115] The specific steps of the method for obtaining the particle backscattering coefficient and the beneficial effects of obtaining it using the terminal provided in this embodiment are the same as those in the above embodiments, and will not be repeated here.

[0116] It should be noted that the memory may include random access memory (RAM) and may also include non-volatile memory, such as at least one disk storage device. Similarly, the processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0117] While the embodiments disclosed in this invention are as described above, the content is merely for the purpose of facilitating understanding of the invention and is not intended to limit the invention. Any person skilled in the art to which this invention pertains may make any modifications and changes in form and detail of the implementation without departing from the spirit and scope disclosed herein; however, the scope of protection of this invention shall still be determined by the scope defined in the appended claims.

Claims

1. A method for obtaining a particle backscattering coefficient, comprising: obtaining wide-angle VSF data of a target sea area, and obtaining corresponding backscattering full-angle volume scattering function data of the wide-angle VSF data by using an interpolation algorithm; obtaining a corresponding backscattering distribution curve based on the backscattering full-angle volume scattering function data; extracting a plurality of corresponding angle values from a first interval, a second interval, a third interval and a fourth interval at a preset interval, respectively, and arranging and combining all the angle values to obtain a plurality of different preset angle combinations; performing polynomial fitting based on each of the preset angle combinations to obtain an estimated backscattering coefficient fitting model corresponding to the backscattering distribution curve; performing polynomial fitting on each preset angle combination to obtain a corresponding fitting result, screening the fitting result with the smallest error from the backscattering distribution curve among all the fitting results, and collecting the fitting result and the corresponding preset angle combination as the estimated backscattering coefficient fitting model; inputting the backscattering full-angle volume scattering function data into the estimated backscattering coefficient fitting model for calculation to obtain a particle backscattering coefficient result; wherein the preset angle combination includes a first angle, a second angle, a third angle and a fourth angle, the first angle is any one of the angle values extracted from the first interval, the second angle belongs to any one of the angle values extracted from the second interval, the third angle belongs to any one of the angle values extracted from the third interval, and the fourth angle belongs to any one of the angle values extracted from the fourth interval, the angle values of the first interval, the second interval, the third interval and the fourth interval increase sequentially, the first interval is 90 degrees to 110 degrees, the second interval is 110 degrees to 130 degrees, the third interval is 130 degrees to 150 degrees, and the fourth interval is 150 degrees to 170 degrees.

2. The particulate backscatter coefficient retrieval method of claim 1, wherein, The method further comprises: obtaining a plurality of polynomial coefficient matrices corresponding to each preset angle combination; obtaining a polynomial coefficient matrix with the smallest error from the backscattering distribution curve as a target polynomial coefficient matrix, and collecting the target polynomial coefficient matrix and the corresponding preset angle combination as the estimated backscattering coefficient fitting model.

3. The method according to claim 2, wherein, The method further comprises: where a represents a polynomial coefficient matrix, θ n represents the nth angle, θ n m represents the mth power of the angle, represents a backscattering distribution curve value.

4. The method of claim 1, wherein, The method further comprises: obtaining a corresponding particle backscattering coefficient theoretical value based on the integral of the backscattering full-angle volume scattering function data in the back hemisphere; obtaining an absolute difference value between the particle backscattering coefficient result and the particle backscattering coefficient theoretical value, if the absolute difference value is greater than a preset threshold, reducing the preset interval and then obtaining the particle backscattering coefficient result again, otherwise outputting the particle backscattering coefficient result as a final result.

5. The method for obtaining a particle backscattering coefficient according to claim 1, wherein the method for obtaining VSF data with an angle value greater than 150 degrees in the wide-angle VSF data comprises: The direct light is sequentially transmitted through the sample cell and the neutral density filter to the exit prism to obtain corresponding reflected light; The reflected light is sequentially transmitted through the sample cell and the neutral density filter to the focusing window to obtain light rays to be measured with an angle greater than 150 degrees; The light rays to be measured are measured by the PMT to obtain VSF data with an angle greater than 150 degrees; The neutral density filter and the exit prism are bonded by Canada gum.

6. The particle backscattering coefficient acquisition method according to claim 1, wherein the preset angle combination further comprises a fifth angle, and the fifth angle is any one angle value selected from 170 degrees to 180 degrees. Comprise:

7. A particle backscatter coefficient acquisition device, characterized by, The data acquisition module is used for acquiring wide-angle VSF data of a target sea area, and acquiring backscattering function data corresponding to the wide-angle VSF data by using an interpolation algorithm; The curve generation module is used for acquiring a backscattering distribution curve corresponding to the backscattering function data based on the backscattering function data; The angle combination module is used for extracting a plurality of corresponding angle values from the first interval, the second interval, the third interval and the fourth interval at a preset interval, respectively, and arranging and combining all the angle values to obtain a plurality of different preset angle combinations; The model screening module is used for performing polynomial fitting based on each preset angle combination to obtain an estimated backscattering coefficient fitting model corresponding to the backscattering distribution curve; performing polynomial fitting on each preset angle combination to obtain a corresponding fitting result, screening the fitting result with the smallest error from the backscattering distribution curve among all the fitting results, and collecting the fitting result and the corresponding preset angle combination as the estimated backscattering coefficient fitting model; The back estimation module is used for inputting the backscattering function data into the estimated backscattering coefficient fitting model for calculation to obtain a particle backscattering coefficient result. In the preset angle combination, a first angle, a second angle, a third angle and a fourth angle are included, the first angle is any one angle value extracted from the first interval, the second angle belongs to any one angle value extracted from the second interval, the third angle belongs to any one angle value extracted from the third interval, and the fourth angle belongs to any one angle value extracted from the fourth interval, the angle values of the first interval, the second interval, the third interval and the fourth interval increase sequentially, the first interval is 90 degrees to 110 degrees, the second interval is 110 degrees to 130 degrees, the third interval is 130 degrees to 150 degrees, and the fourth interval is 150 degrees to 170 degrees. The program is executed by the processor to implement the particle backscattering coefficient acquisition method in any one of claims 1 to 6.

8. A storage medium having stored thereon a computer program, characterized in that The processor and the memory are connected in communication, the memory is used for storing a computer program, and the processor is used for executing the computer program stored in the memory to enable the terminal to execute the particle backscattering coefficient acquisition method in any one of claims 1 to 6.

9. A terminal, characterized by ​

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