Precipitation measurement method, device and equipment based on mixed scanning data and medium

Abstract

The invention provides a rainfall measurement method and device based on mixed scanning data, equipment and a medium. Comprising the following steps: acquiring radar data based on a dual-polarization radar, and determining a target elevation angle and corresponding target radar data according to reflectivity echo characteristics of a plurality of elevation angles corresponding to each azimuth angle in the radar data and corresponding thresholds; determining a plurality of rainfall parameters in the target radar data and membership functions under a plurality of rainfall categories, and determining probability values of the rainfall categories according to the membership functions and parameter weight values of the rainfall parameters under each rainfall category; according to the probability value, the zero-degree layer height, a preset threshold value and continuous detection, determining a target rainfall category from the plurality of rainfall categories; according to the plurality of rainfall parameters, determining a rainfall rule corresponding to the target rainfall category from preset rainfall rules, and substituting the corresponding rainfall parameters into the rainfall rule to obtain a rainfall amount value corresponding to the target radar data; therefore, the accuracy of real-time measurement of the precipitation is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of precipitation measurement, and in particular to a precipitation measurement method and device based on mixed scanning data, equipment and a medium. BACKGROUND

[0002] Meteorological disasters occur frequently. Rainstorms, large-scale and persistent drizzle, thunderstorms and local heavy precipitation occur frequently every year, causing floods, mudslides and other disasters, which seriously affect people's life and property safety and economic life. In order to effectively improve the level of early warning and forecasting of these disastrous weather processes, a more accurate ground precipitation estimation algorithm needs to be developed.

[0003] The existing precipitation measurement method generally uses a rain gauge or a drop spectrometer and radar to observe the precipitation intensity at a point, and determines the precipitation intensity by using a Z-R relationship. Most of them use the classic Z-R relationship and the Z-R grouping relationship fitting scheme in recent years.

[0004] However, the existing precipitation measurement method has the problem of low measurement accuracy. SUMMARY

[0005] The present application provides a precipitation measurement method and device based on mixed scanning data, equipment and a medium to solve the problem of low measurement accuracy of the existing precipitation measurement method.

[0006] In a first aspect, the present application provides a precipitation measurement method based on mixed scanning data, which comprises: Based on the dual-polarization radar, the radar data is obtained, and according to the reflectivity echo characteristics of multiple elevation angles corresponding to each azimuth angle in the radar data and the corresponding threshold value, the target elevation angle and the corresponding target radar data are determined. The target elevation angle is the lowest unobstructed elevation angle corresponding to each azimuth angle. Determine the multiple precipitation parameters in the target radar data and the membership function under multiple precipitation categories, and determine the probability value of the precipitation category according to the membership function and the parameter weight value of each precipitation parameter under each precipitation category. According to the probability value, the zero-degree layer height, the preset threshold value and the continuity detection, the target precipitation category is determined from the multiple precipitation categories; According to the multiple precipitation parameters, the target precipitation category corresponding to the precipitation rule is determined from the preset precipitation rule, and the corresponding precipitation parameters are substituted into the precipitation rule to obtain the precipitation amount value corresponding to the target radar data. In some embodiments of the present application, based on the dual-polarization radar, the radar data is obtained, and according to the reflectivity echo characteristics of multiple elevation angles corresponding to each azimuth angle in the radar data and the corresponding threshold value, the target elevation angle and the corresponding target radar data are determined, comprising: Determine the first threshold value and the second threshold value in the threshold value; determining the reflectivity echo feature greater than the first threshold value as a first target reflectivity echo feature, and determining the reflectivity echo feature greater than a second threshold value as a second target reflectivity echo feature, the second threshold value being greater than the first threshold value; determining an initial elevation angle corresponding to the first target reflectivity echo feature and a feature value, and determining a difference value between feature values of any two adjacent initial elevation angles according to the angle order of the initial elevation angle; determining the number of the difference values greater than the preset difference threshold value as a target reflectivity difference value number; determining a second target reflectivity number corresponding to the second target reflectivity echo feature, and determining the number of the initial elevation angles corresponding to the first target reflectivity echo feature as a target reflectivity number if the second target reflectivity number is greater than a preset number threshold value; determining a target elevation angle according to the target reflectivity difference value number and the target reflectivity number.

[0007] In some embodiments of the present application, the target elevation angle is determined according to the target reflectivity difference value number and the target reflectivity number, including: determining the target reflectivity difference value number and the target reflectivity number corresponding to each data acquisition time according to the plurality of data acquisition times of the dual-polarization radar and the radar data corresponding to the data acquisition times; determining the sum value of the target reflectivity difference value numbers and the sum value of the target reflectivity numbers corresponding to all data acquisition times, and determining the elevation angle division value corresponding to each initial elevation angle in each azimuth angle according to the division value between the sum value of the target reflectivity difference value numbers and the sum value of the target reflectivity numbers; according to the angle order, starting from the initial elevation angle with the largest angle, and sequentially traversing each initial elevation angle and the corresponding next initial elevation angle; if the elevation angle division value corresponding to the initial elevation angle is greater than a preset elevation angle threshold value, and the elevation angle division value of the next initial elevation angle is less than the preset elevation angle threshold value, then the initial elevation angle is determined as the target elevation angle.

[0008] In some embodiments of the present application, the target radar data is determined, and the plurality of precipitation parameters and the membership functions under the plurality of precipitation categories are determined, and the probability value of the precipitation category is determined according to the membership function and the parameter weight value of each precipitation parameter under each precipitation category, including: determining the reflectivity, the differential reflectivity, the cross-correlation coefficient, and the differential phase shift rate in the precipitation parameters; determining the reflectivity deviation corresponding to the reflectivity and the differential phase shift deviation corresponding to the differential phase shift rate according to the plurality of reflectivities and the differential phase shift rates within the radial distance of the target elevation angle; putting the numerical values of the reflectivity, the differential reflectivity, the cross-correlation coefficient, the differential phase shift rate, and the reflectivity deviation and the differential phase shift deviation into the corresponding membership functions respectively to obtain the function values of the membership functions; According to the multiplication of the function value and the corresponding parameter weight value, the probability value of each precipitation parameter under each precipitation category is obtained, and the probability value of each precipitation parameter is added to obtain the probability value of the precipitation category.

[0009] In some embodiments of the present application, a target precipitation category is determined from multiple precipitation categories based on a probability value, a zero-degree layer altitude, a preset threshold, and a continuity test, including: Determine multiple precipitation categories, elevation heights, and bottom and top heights in the zero-degree layer corresponding to the target elevation angle; Compare the elevation angle height and the bottom height to obtain a comparison result; If the comparison result shows that the elevation height is greater than the bottom height, the value of the characteristic value corresponding to the reflectivity echo feature and the preset threshold value are determined; If the characteristic value is less than a preset threshold, it is determined that the multiple precipitation categories corresponding to the target elevation angle do not include mixed precipitation; If the characteristic value is not less than a preset threshold, it is determined that the multiple precipitation categories corresponding to the target elevation angle do not include liquid precipitation; Compare the elevation angle height and the top height to obtain a comparison result; If the comparison result shows that the elevation angle height is less than the top height, it is determined that the multiple precipitation categories corresponding to the target elevation angle do not include solid precipitation; According to the probability values, the target probability value with the largest value among the precipitation categories corresponding to the target elevation angle is determined, and the precipitation category corresponding to the target probability value is determined as the initial precipitation category; Determine multiple initial precipitation categories within the radial distance of the target elevation angle, and perform continuity detection on each initial precipitation category to obtain a detection result; If the detection result shows that the categories corresponding to the two initial precipitation categories before and after the initial precipitation category are the same, and the initial precipitation category is different from the categories corresponding to the two initial precipitation categories before and after, then the category corresponding to the initial precipitation category is adjusted to the category corresponding to the two initial precipitation categories before and after to obtain the target precipitation category; If the detection result shows that the categories corresponding to the two initial precipitation categories on adjacent radial directions at the same radial distance are the same, and the initial precipitation category is different from the categories corresponding to the two initial precipitation categories on the adjacent radial directions, then the category corresponding to the initial precipitation category is adjusted to the category corresponding to the two initial precipitation categories on the adjacent radial directions to obtain the target precipitation category.

[0010] In some embodiments of the present application, based on multiple precipitation parameters, a precipitation rule corresponding to a target precipitation category is determined from preset precipitation rules, and the corresponding precipitation parameters are substituted into the precipitation rule to obtain a precipitation amount value corresponding to the target radar data, including: Determine the differential phase shift rate, reflectivity, differential reflectivity, precipitation value, and empirical coefficients among precipitation parameters; determine a first precipitation rule according to the empirical coefficient, the reflectivity and the precipitation amount value; determine a second precipitation rule according to the empirical coefficient, the differential phase shift rate and the precipitation amount value; determine a third precipitation rule according to the empirical coefficient, the reflectivity, the differential reflectivity and the precipitation amount value; determine a fourth precipitation rule according to the empirical coefficient, the reflectivity, the differential phase shift rate and the precipitation amount value; determine a preset precipitation rule according to the first precipitation rule, the second precipitation rule, the third precipitation rule and the fourth precipitation rule; determine a target precipitation rule corresponding to a target precipitation category from the preset precipitation rule according to the plurality of precipitation parameters.

[0011] In some embodiments of the present application, determining a target precipitation rule corresponding to a target precipitation category from the preset precipitation rule according to the plurality of precipitation parameters comprises: determining respective threshold values corresponding to the target precipitation category, the reflectivity and the differential reflectivity; if the target precipitation category is liquid precipitation, comparing the differential phase shift rate and a preset phase shift threshold value, the reflectivity and a corresponding threshold value, and the differential reflectivity and a corresponding threshold value to obtain a first comparison result; if the target precipitation category is mixed precipitation, comparing the differential phase shift rate and a preset phase shift threshold value to obtain a second comparison result; wherein: if the first comparison result is that the differential phase shift rate is greater than the preset phase shift threshold value, and both the reflectivity and the differential reflectivity are greater than the corresponding threshold values, then determining that the target precipitation rule corresponding to the target precipitation category is the fourth precipitation rule; if the first comparison result is that the differential phase shift rate is greater than the preset phase shift threshold value and the reflectivity is greater than the corresponding threshold value, and the differential reflectivity is not greater than the corresponding threshold value, then determining that the target precipitation rule corresponding to the target precipitation category is the second precipitation rule; if the first comparison result is that the differential phase shift rate is not greater than the preset phase shift threshold value or the reflectivity is not greater than the corresponding threshold value, then determining a comparison result of the differential reflectivity and the corresponding threshold value; when the comparison result of the differential reflectivity and the corresponding threshold value is that the differential reflectivity is greater than the threshold value, then determining that the target precipitation rule corresponding to the target precipitation category is the third precipitation rule; when the comparison result of the differential reflectivity and the corresponding threshold value is that the differential reflectivity is not greater than the threshold value, then determining that the target precipitation rule corresponding to the target precipitation category is the first precipitation rule; wherein: if the second comparison result is that the differential phase shift rate is greater than the preset phase shift threshold value, then determining that the target precipitation rule corresponding to the target precipitation category is the second precipitation rule; If the second comparison result is that the differential phase shift rate is not greater than the preset phase shift threshold, it is determined that the precipitation value corresponding to the lowest elevation angle is zero.

[0012] In a second aspect, the present application provides a precipitation measuring device based on mixed scanning data, the device comprising: The acquisition module is configured to acquire radar data based on a dual-polarization radar, and determine a target elevation angle and corresponding target radar data according to reflectivity echo characteristics of multiple elevation angles corresponding to each azimuth angle in the radar data and corresponding threshold values, the target elevation angle being the lowest unobstructed elevation angle corresponding to each azimuth angle. The probability value determination module is configured to determine multiple precipitation parameters in the target radar data and membership functions under multiple precipitation categories, and determine a probability value of a precipitation category according to the membership functions of each precipitation parameter under each precipitation category and parameter weight values. The category determination module is configured to determine a target precipitation category from the multiple precipitation categories according to the probability value, the zero-degree layer height, a preset threshold value, and continuity detection. The substitution module is configured to determine a precipitation rule corresponding to the target precipitation category from preset precipitation rules according to the multiple precipitation parameters, and substitute the corresponding precipitation parameters into the precipitation rule to obtain a precipitation value corresponding to the target radar data.

[0013] In a third aspect, the present application provides a device comprising a processor and a memory connected to the processor in communication; The memory stores computer execution instructions; The processor executes the computer execution instructions stored in the memory to implement the method of the present application.

[0014] In a fourth aspect, the present application provides a computer-readable storage medium, which stores program codes, the program codes being executed by a processor to implement the method of the present application.

[0015] The present application provides a precipitation measuring method, device, equipment and medium based on mixed scanning data, which acquires radar data based on a dual-polarization radar, and determines a target elevation angle and corresponding target radar data according to reflectivity echo characteristics of multiple elevation angles corresponding to each azimuth angle in the radar data and corresponding threshold values; determines multiple precipitation parameters in the target radar data and membership functions under multiple precipitation categories, and determines a probability value of a precipitation category according to the membership functions of each precipitation parameter under each precipitation category and parameter weight values; determines a target precipitation category from the multiple precipitation categories according to the probability value, the zero-degree layer height, a preset threshold value, and continuity detection; and determines a precipitation rule corresponding to the target precipitation category from preset precipitation rules according to the multiple precipitation parameters, and substitutes the corresponding precipitation parameters into the precipitation rule to obtain a precipitation value corresponding to the target radar data.

[0016] Thus, the lowest elevation angle mixed scanning data for precipitation estimation can be obtained by using the volume scanning data of the wave band dual polarization radar for a certain time to statistically analyze the echo characteristics between different elevation angles in the same azimuth with and without obstruction. Then, the precipitation category classification is performed by using the water condensate identification. The precipitation category error correction is performed by using the zero layer bright band, the preset threshold and the continuity detection. Finally, the precipitation estimation and calibration are performed by using the precipitation data matching of the simultaneous time and space dual polarization radar, the raindrop spectrometer and the rain gauge data and other precipitation measuring equipment. BRIEF DESCRIPTION OF DRAWINGS

[0017] The accompanying drawings, which are incorporated herein and form a part of the specification, illustrate embodiments consistent with the present application and, together with the description, further serve to explain the principles of the application.

[0018] Figure 1 A flowchart of a precipitation measurement method based on mixed scanning data provided by an embodiment of the present application; Figure 2 A method diagram of a precipitation measurement method based on mixed scanning data provided by an embodiment of the present application; Figure 3 A data extraction flowchart of a precipitation measurement method based on mixed scanning data provided by an embodiment of the present application; Figure 4 A structure diagram of a target object recognition device provided by an embodiment of the present application; Figure 5 A structure block diagram of a device for performing a precipitation measurement method based on mixed scanning data according to an embodiment of the present application. DETAILED DESCRIPTION

[0019] The exemplary embodiments will be described in detail herein with reference to the attached drawings. The following description is made with reference to the accompanying drawings in which like reference numerals represent like elements, unless the context of use indicates otherwise. The following description of exemplary embodiments is not representative of all embodiments consistent with the present application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of the present application as detailed in the appended claims.

[0020] The technical solutions of the present application and how the technical solutions of the present application solve the above technical problems will be described in detail in the following specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes can not be described again in some embodiments. The embodiments of the present application will be described below with reference to the accompanying drawings.

[0021] In the prior art, the current mixed scan elevation angle usually utilizes digital elevation terrain data, radar station latitude and longitude height information, radar beam mode and radar beam propagation path to determine the lowest unobstructed elevation angle by calculating the beam obstruction rate. Firstly, only the main obstruction information is included in the terrain data, and the obstruction information actually derived from trees, artificial buildings and the like is not included in the terrain data. Secondly, the latitude and longitude height information of the radar station is inaccurate, and with the development of society and urban construction, new buildings, trees and the like are continuously emerging, which will cause a large error in the calculation of the mixed scan elevation angle, thereby causing an error in the radar precipitation measurement.

[0022] In view of the above problems, the volume scan data of the X-band dual-polarization radar in a certain time is used to statistically analyze the echo characteristics between the unobstructed and obstructed same-azimuth different-elevation angles, so as to obtain the mixed scan data of the lowest elevation angle for precipitation estimation. Secondly, the water condensate identification, zero layer height and hard threshold value combination, one-dimensional and two-dimensional radial continuity detection are used for precipitation category classification. Finally, the precipitation data of the simultaneous time and space dual-polarization radar, the raindrop spectrometer and the rain gauge and other precipitation measurement equipment are matched to obtain the related parameters of the classified precipitation estimation for precipitation estimation and calibration. Thus, the influence of the terrain and the phase state on the precipitation estimation is reduced, and the accuracy of the radar precipitation estimation is improved.

[0023] Figure 1 A flowchart of a precipitation measurement method based on mixed scan data provided by the embodiment of the present application is shown in FIG. 1. Figure 1 As shown in FIG. 1, the precipitation measurement method based on mixed scan data can include the following steps: S110, based on the dual-polarization radar, acquiring radar data, and determining the target elevation angle and the corresponding target radar data according to the reflectivity echo characteristics of a plurality of elevation angles corresponding to each azimuth angle in the radar data and the corresponding threshold value, the target elevation angle being the lowest unobstructed elevation angle corresponding to each azimuth angle.

[0024] The dual-polarization radar is an X-band dual-polarization radar, which is a radar device working in the X-band (wavelength about 2.4 cm-3.75 cm) and having the ability to simultaneously transmit and receive electromagnetic waves in horizontal and vertical polarization directions. The X-band dual-polarization radar has high space-time resolution when detecting in a short distance, and it can not only obtain basic echo parameters in the horizontal direction, but also obtain a plurality of high-precision echo parameters according to the information fed back by the horizontal and vertical two propagation channels. Therefore, the X-band dual-polarization parameters can reflect more abundant microphysical field information in the cloud and precipitation process.

[0025] Azimuth is the angle of radar antenna beam pointing in the horizontal plane, with the direction of true north as 0°, and the angle of the beam pointing clockwise (range: 0°~360°), used to describe the azimuthal position of the radar detected target in the horizontal plane, for example, a certain echo appears at azimuth 90° (true east direction), 50 km away from the radar station.

[0026] In the field of radar detection, the elevation angle is the angle between the center line of the radar antenna beam and the horizontal plane, usually in degrees (°); the radar can scan at different elevations (such as 0.5°, 1.4°, 2.3°, etc.) under the same azimuth angle, forming multiple elevation angle layers of data, for example: at azimuth 90° (true east direction), the radar can simultaneously obtain 0.5° elevation angle layer (near ground) and 5° elevation angle layer (high altitude) data, both with the same azimuth angle but different elevations.

[0027] The target elevation angle is the minimum radar detection elevation angle for each azimuth angle that is not blocked by terrain or ground objects, that is, the beam emitted by the radar at this elevation angle will not be blocked by surrounding terrain, buildings, trees and other obstacles, and can effectively obtain near-ground precipitation echo data.

[0028] Reflectivity echo characteristics are a key indicator in the field of radar remote sensing, weather radar, etc. to describe the ability of a target to reflect radar waves, and its characteristics can reflect information such as the physical properties and structural morphology of the target; reflectivity echo refers to the signal strength of the electromagnetic wave emitted by the radar that is reflected back after encountering a target and received by the radar, and reflectivity (usually represented by dBZ, decibel per Z unit) is a physical quantity that measures echo intensity, the higher the value, the stronger the ability of the target to reflect radar waves, usually represented by the symbol Z, with a unit of dBZ (decibel•square meter / cubic meter).

[0029] The corresponding threshold is a pre-set threshold corresponding to the reflectivity, used to determine whether the reflectivity meets the threshold requirement, so as to further process the reflectivity.

[0030] Based on this, data is acquired based on an X-band dual-polarization radar, so as to determine the lowest elevation angle that can effectively obtain data and is not blocked at each azimuth angle according to the reflectivity echo characteristics corresponding to multiple elevations at each azimuth angle in the radar data and the corresponding threshold, the lowest elevation angle is close to the ground and is not blocked, and the data obtained is more accurate, so as to subsequently determine the real-time precipitation category and measure and calculate the real-time precipitation amount according to the radar data of the lowest elevation angle.

[0031] S120, determine the multiple precipitation parameters in the target radar data and the membership functions under the multiple precipitation categories, and determine the probability value of the precipitation category according to the membership functions and parameter weight values of each precipitation parameter under each precipitation category.

[0032] The precipitation parameters are parameters related to the precipitation category and the precipitation amount in the radar data corresponding to the lowest elevation angle, for example, can include reflectivity , differential reflectivity , correlation coefficient , differential phase rate , and reflectivity corresponding reflectivity deviation and differential phase standard deviation and differential phase rate corresponding differential phase deviation and the like.

[0033] The precipitation category is a real-time precipitation category, which can be liquid precipitation, solid precipitation, or mixed precipitation, the liquid precipitation can be heavy rain, small to medium rain, heavy rain, etc., the solid precipitation can be hail, dry snow, etc., and the mixed precipitation is simultaneous liquid precipitation and solid precipitation, for example, sleet state.

[0034] The membership function is a mathematical function constructed based on fuzzy logic theory for each radar polarization parameter, which is used to describe the membership probability of the parameter belonging to a certain type of precipitation particle (liquid / solid / mixed), and the fuzzy logic is a mathematical method for dealing with uncertainty problems, which describes the degree of an element belonging to a certain class through "membership degree" (a value between 0 and 1), rather than the traditional "either-or" binary judgment.

[0035] The parameter weight value is a numerical value of the weight corresponding to the probability value of each precipitation parameter, which is obtained by assigning a corresponding weight to the probability value of each precipitation category calculated for each precipitation parameter, so as to comprehensively determine the probability of each precipitation category according to multiple precipitation parameters, in order to determine the actual corresponding precipitation category.

[0036] Therefore, by determining the precipitation parameters in the radar data of the lowest elevation angle, and determining the membership function corresponding to the precipitation parameters in each precipitation category, the function value of the membership function corresponding to each precipitation parameter in each precipitation category is obtained by substituting the precipitation parameters into the corresponding membership function, and the product value of each precipitation parameter is determined according to the function value of each precipitation parameter and the parameter weight value, so as to further determine the sum value of the product value of all precipitation parameters in the precipitation category, and obtain the probability value corresponding to the precipitation category.

[0037] S130, determining a target precipitation category from the plurality of precipitation categories according to the probability value, the zero-degree layer height, the preset threshold, and the continuity detection.

[0038] The zero-degree layer height refers to the height corresponding to the zero-degree layer. The region with a temperature of 0 DEG C in the atmosphere is usually not a strict "surface", but a "layer" with a certain thickness (because the temperature change in the vertical direction can be relatively flat), which is called the zero-degree layer. This layer is the key boundary of the change of water phase. Above the zero-degree layer, water vapor is easy to condense into ice crystals, snowflakes or supercooled water droplets. Below the zero-degree layer, ice crystals and snowflakes can melt into raindrops.

[0039] Based on this, the probability value corresponding to each precipitation category is determined, so that the target precipitation category is determined from the plurality of precipitation categories according to the probability value, the zero-degree layer height, the preset threshold value and the continuity detection.

[0040] In S140, the target precipitation category corresponding to the precipitation rule is determined from the preset precipitation rule according to the plurality of precipitation parameters, and the corresponding precipitation parameters are substituted into the precipitation rule to obtain the precipitation amount value corresponding to the target radar data.

[0041] The precipitation parameters corresponding to the precipitation rule refer to the parameters contained in the precipitation rule. For example, the precipitation rule is R represents the precipitation amount value, and b is an empirical coefficient, The reflectivity is represented by Z, and the precipitation parameter is the reflectivity .

[0042] Based on this, the precipitation amount corresponding to the lowest elevation angle is calculated by substituting the precipitation parameters into the determined precipitation rule, so as to realize accurate estimation of real-time precipitation amount.

[0043] Based on the above feasible implementation manner of S110, the present application further provides a method for obtaining radar data based on a dual-polarization radar and determining a target elevation angle and corresponding target radar data according to the reflectivity echo characteristics of a plurality of elevation angles corresponding to each azimuth angle in the radar data and the corresponding threshold value, comprising the steps of: determining a first threshold value and a second threshold value in the threshold value; determining the reflectivity echo characteristics greater than the first threshold value as the first target reflectivity echo characteristics, and the reflectivity echo characteristics greater than the second threshold value as the second target reflectivity echo characteristics, the value of the second threshold value being greater than the value of the first threshold value; determining the initial elevation angle and the characteristic value corresponding to the first target reflectivity echo characteristics, and determining the difference value between the characteristic values of any two adjacent initial elevation angles according to the angle size order of the initial elevation angle; determining the number of difference values greater than the preset difference value threshold value as the target reflectivity difference value number; determining a second target reflection quantity corresponding to the second target reflectivity echo feature, and if the second target reflection quantity is greater than a preset quantity threshold, determining the initial elevation angle corresponding to the first target reflectivity echo feature as the target reflection quantity; determining the target elevation angle according to the target reflection difference quantity and the target reflection quantity.

[0044] The angle size order is an angle size arrangement order between the elevation angles determined according to the angle values corresponding to the elevation angles. For example, the radar can obtain multiple elevation angles (such as 0.5°, 2.3°, 1.4°, etc.) at the same azimuth angle, and the size order of the three elevation angles is 2.3°, 1.4°, 0.5° or 0.5°, 1.4°, 2.3°.

[0045] The first threshold and the second threshold are thresholds used for comparison with the reflectivity of the elevation angle. The first threshold can be valued in the range of 0-10 dBZ, and the second threshold can be valued in the range of 13-18 dBZ.

[0046] The preset difference threshold is a preset threshold used for comparison with the reflectivity difference between the target elevation angle, and can be valued in the range of 7-10 dBZ.

[0047] The preset quantity threshold is a preset threshold used for comparison with the number of the target elevation angles whose reflectivity is greater than the second threshold, and can be valued in the range of 25-100.

[0048] Based on this, the initial elevation angle whose reflectivity echo feature is greater than the first threshold in the multiple elevation angles corresponding to each azimuth angle is determined, and the target elevation angle is arranged according to the angle size order, so as to determine the reflectivity difference value corresponding to any two adjacent initial elevation angles, and determine whether the reflectivity difference value is greater than the preset difference threshold, if yes, record the reflectivity; and determine the number of the elevation angles whose reflectivity is greater than the second threshold in the multiple elevation angles.

[0049] On the basis of the feasible implementation manner of S110, the application further provides a method for determining the target elevation angle according to the target reflection difference quantity and the target reflection quantity, comprising the steps of: determining the target reflection difference quantity and the target reflection quantity corresponding to each data acquisition time according to the multiple data acquisition times of the dual-polarization radar and the radar data corresponding to the data acquisition times; determining the sum value of the target reflection difference quantity and the sum value of the target reflection quantity corresponding to all the data acquisition times, and determining the elevation angle division value corresponding to each initial elevation angle at each azimuth angle according to the division value between the sum value of the target reflection difference quantity and the sum value of the target reflection quantity; according to the angle size order, starting from the initial elevation angle with the largest angle, and sequentially traversing each initial elevation angle and the corresponding next initial elevation angle; If the elevation angle division value corresponding to the initial elevation angle is greater than the preset elevation angle threshold, and the elevation angle division value of the next initial elevation angle is less than the preset elevation angle threshold, the initial elevation angle is determined as the target elevation angle.

[0050] The plurality of data acquisition time points are time points corresponding to data acquisition of the X-band dual-polarization radar on the same region at different time points, and the number of data acquisition time points can be represented by N, N>=3.

[0051] The preset elevation angle threshold is a threshold preset for comparison with the elevation angle division value of the target elevation angle, and can be valued in the range of 30% to 60%.

[0052] Therefore, by acquiring data corresponding to the elevation angles at the plurality of data acquisition time points, the target reflection difference value number and the target reflection number corresponding to each elevation angle at different data acquisition time points are determined, the number of the plurality of data acquisition time points is summed, the sum of the target reflection difference value number and the target reflection number at all data acquisition time points are obtained, and the elevation angle division value corresponding to each initial elevation angle at each azimuth angle is determined. The elevation angle division value can represent the radar echo characteristics of each elevation angle, so that the elevation angle division value corresponding to the plurality of initial elevation angles with the reflectivity greater than the first reflectivity threshold at each azimuth angle is determined, and the angles are sequentially traversed from high to low elevation angles according to the angle size order, so that the first elevation angle division value greater than the preset elevation angle threshold is determined. If the elevation angle threshold of the current initial elevation angle is greater than the preset elevation angle threshold, and the elevation angle threshold of the next initial elevation angle is less than the preset elevation angle threshold, the elevation angle division value of the current initial elevation angle is determined as the first elevation angle division value greater than the preset elevation angle threshold, and the current initial elevation angle is determined as the target elevation angle corresponding to the azimuth angle.

[0053] On the basis of the feasible implementation manner of S120, the application further provides determination of a plurality of precipitation parameters in the target radar data and membership functions under a plurality of precipitation categories, and determination of a probability value of a precipitation category according to the membership function and the parameter weight value of each precipitation parameter under each precipitation category, comprising the steps of: Determining reflectivity, differential reflectivity, cross-correlation coefficient, and differential phase shift rate in the precipitation parameters. Determining reflectivity deviation corresponding to the reflectivity and differential phase shift deviation corresponding to the differential phase shift rate according to the plurality of reflectivity and differential phase shift rate within the radial distance of the target elevation angle. Substituting the values of the reflectivity, the differential reflectivity, the cross-correlation coefficient, the differential phase shift rate, and the reflectivity deviation and the differential phase shift deviation into the corresponding membership functions respectively to obtain the function values of the membership functions. According to the multiplication value of the function value and the corresponding parameter weight value, the probability value of each precipitation parameter under each precipitation category is obtained, and the probability values of the precipitation parameters are added to obtain the probability value of the precipitation category.

[0054] wherein, the differential reflectivity is one of the key detection parameters of the X-band dual-polarization radar, and is used to represent the difference between the horizontal polarization (H) and the vertical polarization (V) electromagnetic wave reflectivity.

[0055] The radial distance refers to the straight line distance from the center of the radar antenna to the detection target along the center line of the radar beam, and is usually measured in kilometers (km). In the radar polar coordinate system, each detection data point is uniquely determined by the azimuth angle, the radial distance and the elevation angle, forming the position coordinates in the three-dimensional space.

[0056] The reflectivity bias refers to the standard deviation of multiple reflectivities in the radial distance, and the differential phase bias refers to the standard deviation of multiple differential phase rates in the radial distance.

[0057] For example, the reflectivity can be represented by , the reflectivity bias can be represented by , the differential reflectivity can be represented by , and the differential phase bias can be represented by . Then

[0058]

[0059] is the calculation range in the radial direction, which can be 1 km, for example; and are the mean values of the reflectivity and the differential phase rate in the radial distance range, respectively.

[0060] The correlation coefficient is used to represent the linear correlation degree between the horizontal polarization echo signal and the vertical polarization echo signal, and the value range is 0-1, which can be represented by .

[0061] In practical applications, the probability value can be represented by , and then

[0062] wherein, is the measurement parameter matrix of the dual-line polarization Doppler radar, is the first independent of .​ The weight coefficient of each polarization parameter ranges from 0 to 1. For the The polarization parameters are for The membership function is established for each precipitation particle type, and M is the number of polarization radar measurement parameters used for precipitation particle type identification.

[0063] Based on this, by determining the reflectivity, differential reflectivity, mutual correlation coefficient, and differential phase shift rate among the precipitation parameters, and further determining the corresponding reflectivity deviation based on the reflectivity, and determining the corresponding differential phase shift deviation based on the differential phase shift rate, the reflectivity, differential reflectivity, mutual correlation coefficient, differential phase shift rate, reflectivity deviation, and differential phase shift deviation are respectively substituted into the probability value calculation of the corresponding precipitation category to obtain the probability values ​​of different precipitation categories corresponding to each precipitation parameter, and the probability values ​​of all precipitation parameters corresponding to each precipitation category are added and summed, so as to determine that the precipitation category corresponding to the probability value with the largest probability value is the target precipitation category.

[0064] Based on the feasible implementation of the above S130, the present application further provides a method of determining the precipitation category corresponding to the target probability value having the largest value among the probability values ​​as the target precipitation category, and determining the precipitation rule corresponding to the target precipitation category from preset precipitation rules based on the differential phase shift rate and the preset phase shift threshold among the multiple precipitation parameters, including the following steps: Determine multiple precipitation categories, elevation heights, and bottom and top heights in the zero-degree layer corresponding to the target elevation angle; Compare the elevation angle height and the bottom height to obtain a comparison result; If the comparison result shows that the elevation height is greater than the bottom height, the value of the characteristic value corresponding to the reflectivity echo feature and the preset threshold value are determined; If the characteristic value is less than a preset threshold, it is determined that the multiple precipitation categories corresponding to the target elevation angle do not include mixed precipitation; If the characteristic value is not less than a preset threshold, it is determined that the multiple precipitation categories corresponding to the target elevation angle do not include liquid precipitation; Compare the elevation angle height and the top height to obtain a comparison result; If the comparison result shows that the elevation angle height is less than the top height, it is determined that the multiple precipitation categories corresponding to the target elevation angle do not include solid precipitation; According to the probability values, the target probability value with the largest value among the precipitation categories corresponding to the target elevation angle is determined, and the precipitation category corresponding to the target probability value is determined as the initial precipitation category; Determine multiple initial precipitation categories within the radial distance of the target elevation angle, and perform continuity detection on each initial precipitation category to obtain a detection result; If the detection result is that the categories corresponding to the two initial precipitation categories before and after the initial precipitation category are the same, and the category corresponding to the initial precipitation category is different from the categories corresponding to the two initial precipitation categories before and after the initial precipitation category, the category corresponding to the initial precipitation category is adjusted to the categories corresponding to the two initial precipitation categories before and after the initial precipitation category, to obtain the target precipitation category. If the detection result is that the categories corresponding to the two initial precipitation categories at the same radial distance on the adjacent radial direction of the initial precipitation category are the same, and the category corresponding to the initial precipitation category is different from the categories corresponding to the two initial precipitation categories on the adjacent radial direction, the category corresponding to the initial precipitation category is adjusted to the categories corresponding to the two initial precipitation categories on the adjacent radial direction, to obtain the target precipitation category.

[0065] In practical applications, the method of combining the zero-degree layer top height , the zero-degree layer bottom height , and the hard threshold value is used to identify and correct the error classification of the precipitation category; When , it cannot be determined as solid precipitation; When , it cannot be determined as liquid precipitation; When and , it cannot be determined as mixed precipitation.

[0066] One-dimensional and two-dimensional continuity can also be further used to correct the error classification of the precipitation category, for example: one-dimensional continuity detection is performed on the precipitation category data of each bin in each radial direction, and the error classification of the precipitation category is corrected. The correction method is: when the precipitation category results of the two bins before and after the to-be-detected bin are consistent, and the to-be-detected bin is inconsistent, the precipitation category of the to-be-detected bin is corrected to the precipitation category of the bin before and after the to-be-detected bin; or two-dimensional continuity detection is performed on the precipitation category data of each bin in the current radial direction using the adjacent radial direction, and the error classification of the precipitation category is corrected. The correction method is: when the precipitation category results of the two bins at the same distance on the adjacent radial direction of the to-be-detected bin are consistent, and the to-be-detected bin is inconsistent, the precipitation category of the to-be-detected bin is corrected to the precipitation category of the bin at the same distance on the adjacent radial direction.

[0067] On the basis of the feasible implementation manner of S140 described above, the present application further provides that, according to a plurality of precipitation parameters, a target precipitation category corresponding to a precipitation rule is determined from a preset precipitation rule, and the corresponding precipitation parameters are substituted into the precipitation rule to obtain a target radar data corresponding to a precipitation quantity value, comprising the steps of: determining a differential phase shift rate, reflectivity, differential reflectivity, precipitation quantity value, and empirical coefficient in the precipitation parameters; determining a first precipitation rule according to the empirical coefficient, reflectivity, and precipitation quantity value; determining a second precipitation rule according to the empirical coefficient, differential phase shift rate, and precipitation quantity value; The third precipitation rule is determined according to the empirical coefficient, the reflectivity, the differential reflectivity and the precipitation quantity value; The fourth precipitation rule is determined according to the empirical coefficient, the reflectivity, the differential phase shift and the precipitation quantity value; The preset precipitation rule is determined according to the first precipitation rule, the second precipitation rule, the third precipitation rule and the fourth precipitation rule; The precipitation rule corresponding to the target precipitation category is determined from the preset precipitation rule according to the plurality of precipitation parameters.

[0068] The empirical coefficient can include a first empirical coefficient a, a second empirical coefficient b and a third empirical coefficient c, the reflectivity can be represented by R, the differential reflectivity can be represented by Kdp, the differential phase shift can be represented by φdp, and the precipitation quantity value can be represented by R. The first precipitation rule is , the second precipitation rule is , the third precipitation rule is , and the fourth precipitation rule is .

[0069] Therefore, the preset first precipitation rule, the second precipitation rule, the third precipitation rule and the fourth precipitation rule are determined, so that the precipitation rule corresponding to the target precipitation category is determined from the preset precipitation rule according to the precipitation parameters, and the precipitation parameters are brought into the corresponding precipitation rule after being preprocessed, so as to calculate the precipitation quantity value.

[0070] Based on the above feasible implementation manner of S140, the application further provides a method for determining the precipitation rule corresponding to the target precipitation category from the preset precipitation rule according to the plurality of precipitation parameters, which comprises the following steps: Determine the threshold values corresponding to the target precipitation category, the reflectivity and the differential reflectivity respectively; If the target precipitation category is liquid precipitation, compare the differential phase shift with the preset phase shift threshold value, the reflectivity with the corresponding threshold value, and the differential reflectivity with the corresponding threshold value to obtain a first comparison result; If the target precipitation category is mixed precipitation, compare the differential phase shift with the preset phase shift threshold value to obtain a second comparison result; If the first comparison result is that the differential phase shift is greater than the preset phase shift threshold value, and the reflectivity and the differential reflectivity are both greater than the corresponding threshold values, the precipitation rule corresponding to the target precipitation category is determined as the fourth precipitation rule; ​​​​If the first comparison result is that the differential phase shift rate is greater than the preset phase shift threshold and the reflectivity is greater than the corresponding threshold, and the differential reflectivity is not greater than the corresponding threshold, then the target precipitation category corresponding precipitation rule is determined to be the second precipitation rule; If the first comparison result is that the differential phase shift rate is not greater than the preset phase shift threshold or the reflectivity is not greater than the corresponding threshold, then the comparison result of the differential reflectivity and the corresponding threshold is determined. When the comparison result of the differential reflectivity and the corresponding threshold is that the differential reflectivity is greater than the threshold, then the target precipitation category corresponding precipitation rule is determined to be the third precipitation rule. When the comparison result of the differential reflectivity and the corresponding threshold is that the differential reflectivity is not greater than the threshold, then the target precipitation category corresponding precipitation rule is determined to be the first precipitation rule. Wherein: If the second comparison result is that the differential phase shift rate is greater than the preset phase shift threshold, then the target precipitation category corresponding precipitation rule is determined to be the second precipitation rule. If the second comparison result is that the differential phase shift rate is not greater than the preset phase shift threshold, then the lowest elevation angle corresponding precipitation amount value is determined to be zero.

[0071] Based on this, in actual application, when the precipitation category is liquid precipitation, and the differential phase shift rate is less than the set threshold or the reflectivity is less than the set reflectivity threshold , further judge the size of the differential reflectivity , when is not greater than the set threshold , it is determined that the current corresponds to the first precipitation rule; when is greater than the set threshold , it is determined that the current corresponds to the third precipitation rule.

[0072] When the precipitation category is liquid precipitation, and the differential phase shift rate is greater than the set threshold and the reflectivity is greater than the set reflectivity threshold , further judge the size of the differential reflectivity , when is not greater than the set threshold , it is determined that the current corresponds to the second precipitation rule; when is greater than the set threshold , it is determined that the current corresponds to the fourth precipitation rule.

[0073] When the precipitation type is mixed precipitation, it is further determined whether the difference phase shift rate is greater than a set threshold value . When the difference phase shift rate is greater than the set threshold value , it is determined that the current corresponds to the second precipitation rule, otherwise the sample is rejected.

[0074] When the precipitation type is identified as solid precipitation, the sample is rejected. The set threshold value is 0.3-0.5; the set threshold value is 0.5-1; the set reflectivity threshold value is 35-40 ; and the sample rejection condition indicates that the precipitation estimation is invalid.

[0075] Further, the precipitation estimation result is gridded to obtain gridded precipitation estimation data; then, original gridded rainfall data for a certain time is obtained by linear average accumulation method; and rain gauge data within a certain range is searched to calibrate the precipitation estimation.

[0076] If there is rain gauge data within a set distance threshold value , the nearest rain gauge data is used to calibrate the precipitation estimation; if there is rain gauge data within the set distance threshold value and , and the number of rain gauges is greater than a set rain gauge number threshold value , the precipitation estimation is calibrated according to a distance weight method; the set time threshold value is 15-30 ; the set distance threshold value is 500-1500 ; the set distance threshold value is 3000-5000 ; and the set rain gauge number threshold value is at least 2.

[0077] Please refer to Figure 2 , Figure 2 a method schematic diagram of a precipitation measurement method based on mixed scanning data provided by the embodiments of the present application; as Figure 2 ​​​As shown, the raw data of the wave band dual polarization weather radar detection is acquired in real time, and quality control is performed thereon, which includes scatter noise, radial interference, clear sky echo, ground echo, dual polarization parameter quality control and attenuation correction, etc. The dual polarization data after quality control for a certain time is acquired, and according to the fact that the echo characteristics on the same azimuth and different elevation angles have obvious differences when the radar is unobstructed and obstructed, the lowest scanning elevation angle in each azimuth is obtained through statistical analysis of the echo changes of each elevation layer of the wave band radar after quality control for a certain time, so that the mixed scanning data for precipitation inversion is obtained. The output mixed scanning data is used to select characteristic quantities to perform precipitation category recognition based on the fuzzy logic method, and the recognition is divided into three categories, including liquid precipitation, solid precipitation and mixed precipitation. The raw data of the radar after quality control, the data of the raindrop spectrometer, the data of the rain gauge and other precipitation measuring devices are used to fit the precipitation rules, and the mixed scanning data, the precipitation category recognition result and the zero degree layer height are combined to realize the estimation of the real-time precipitation amount by the dual polarization radar. Finally, the estimated precipitation amount is adjusted by using the data of the rain gauge and other precipitation measuring devices, so as to improve the accuracy of the final obtained precipitation amount.

[0078] Please refer to Figure 3 , Figure 3 The data extraction flowchart of the precipitation measurement method based on mixed scanning data provided by the embodiment of the application is shown in FIG. 1. Figure 3 As shown, the data of each elevation layer in the volume scanning data acquired in real time is processed according to the azimuth angle resolution. The average or maximum value of a plurality of radial data meeting the condition in the same azimuth angle is calculated. The difference value of the reflectivity of the adjacent two elevation layers in the same azimuth angle is calculated. Then the number of valid data of the difference value in the radial data of the azimuth angle is counted, and the number of data greater than the reflectivity threshold value in the radial data of each azimuth angle in each elevation layer is counted. If the number is greater than the set single radial valid data number threshold value, the number of data greater than the set reflectivity threshold value in the radial data of the azimuth angle is further counted. Otherwise, the radial data of the azimuth angle is 0. The number of all original valid data and the number of all difference values in the same azimuth angle of the same elevation angle are counted by using the volume scanning data at a plurality of time points, and the difference value proportion is calculated. Starting from the high elevation angle to the low elevation angle, the first proportion value greater than the set difference value proportion threshold value in each azimuth angle is found, and the elevation angle corresponding to the value is the minimum unobstructed elevation angle in the azimuth angle.

[0079] In some embodiments of the present application, by statistically analyzing the echo changes of each elevation layer of the wave band radar after a certain time quality control, the lowest scanning elevation angle in each direction is obtained, so as to quickly obtain mixed scanning data, provide radar detection data closest to the terrain for subsequent precipitation estimation, and improve the accuracy of precipitation estimation. Compared with the traditional method of using data elevation terrain data and observing terrain tools, the method only needs to analyze a period of data, can update in real time according to the terrain, has low application cost, is easy to automate, does not need manual operation, is simple, fast and efficient, is easy to implement and apply in engineering, and can effectively obtain mixed scanning data. The method uses the zero layer bright band and hard threshold result method and the one-dimensional and two-dimensional continuity detection method to identify the error classification, improves the accuracy of precipitation category identification, reduces the precipitation estimation error caused by abnormal phase results, provides better classification application for subsequent precipitation inversion classification, obtains the lowest scanning data for precipitation inversion through the mixed scanning data extraction method, and obtains the classification precipitation estimation related parameters that best match the current environment through the raindrop spectrometer, rain gauge, radar and other precipitation measurement equipment matching methods, and reduces the large error caused by the abnormal data of the raindrop spectrometer or rain gauge when used alone. It is applicable to plains or complex terrain areas. At the same time, combined with the precipitation category identification and zero layer height data, the influence of non-precipitation data is eliminated, the precipitation estimation error caused by abnormal phase identification is reduced, and finally the rain gauge data is used for precipitation calibration.

[0080] In this way, the influence of terrain, phase state and the like on precipitation estimation can be reduced, incorrect precipitation fitting can be reduced, and the accuracy of precipitation estimation can be greatly improved. The method can provide a reference for meteorological, water conservancy and other related disaster prediction and warning, and can be applied.

[0081] Figure 4 A structure diagram of a precipitation measurement device 400 based on mixed scanning data provided by an embodiment of the present application is shown in FIG. 4. Figure 4 As shown in the figure, the precipitation measurement device 400 based on mixed scanning data includes an acquisition module 410, a probability value determination module 420, a category determination module 430, and an input module 440. The acquisition module 410 is configured to acquire radar data based on a dual-polarization radar, and determine a target elevation angle and corresponding target radar data according to the reflectivity echo characteristics of a plurality of elevation angles corresponding to each azimuth angle in the radar data and the corresponding threshold value. The target elevation angle is the lowest unobstructed elevation angle corresponding to each azimuth angle. The probability value determination module 420 is configured to determine a plurality of precipitation parameters and membership functions under a plurality of precipitation categories in the target radar data, and determine a probability value of the precipitation category according to the membership functions of each precipitation parameter under each precipitation category and the parameter weight value. The category determination module 430 is configured to determine a target precipitation category from the plurality of precipitation categories according to the probability value, the zero-degree layer height, a preset threshold value, and continuity detection. The substitution module 440 is configured to determine a precipitation rule corresponding to the target precipitation category from a plurality of preset precipitation rules according to the plurality of precipitation parameters, and substitute the corresponding precipitation parameters into the precipitation rule to obtain a precipitation quantity value corresponding to the target radar data.

[0082] In the embodiments of the present application, the acquisition module 410 can be specifically configured to: determine a first threshold value and a second threshold value in the threshold value; determine a first target reflectivity echo feature as the reflectivity echo feature greater than the first threshold value, and determine a second target reflectivity echo feature as the reflectivity echo feature greater than the second threshold value, the value of the second threshold value being greater than the value of the first threshold value; determine an initial elevation angle and a feature value corresponding to the first target reflectivity echo feature, and determine a difference value between the feature values of any two adjacent initial elevation angles according to the angle size order of the initial elevation angle; determine the number of the difference values greater than the preset difference threshold value as a target reflectivity difference value number; determine a second target reflectivity number corresponding to the second target reflectivity echo feature, and if the second target reflectivity number is greater than a preset number threshold value, determine the number of the initial elevation angles corresponding to the first target reflectivity echo feature as a target reflectivity number; determine a target elevation angle according to the target reflectivity difference value number and the target reflectivity number.

[0083] In the embodiments of the present application, the acquisition module 410 can be specifically configured to: determine the target reflectivity difference value number and the target reflectivity number corresponding to each data acquisition time according to a plurality of data acquisition times of the dual-polarization radar and the radar data corresponding to the data acquisition times; determine a sum value of the target reflectivity difference value numbers corresponding to all data acquisition times and a sum value of the target reflectivity numbers, and determine an elevation angle division value corresponding to each initial elevation angle in each azimuth angle according to a division value between the sum value of the target reflectivity difference value numbers and the sum value of the target reflectivity numbers; according to the angle size order, starting from the initial elevation angle with the largest angle, sequentially traverse each initial elevation angle and the corresponding next initial elevation angle; If the elevation angle division value corresponding to the initial elevation angle is greater than the preset elevation angle threshold value, and the elevation angle division value of the next initial elevation angle is less than the preset elevation angle threshold value, the initial elevation angle is determined as the target elevation angle.

[0084] In the embodiment of the present application, the probability value determination module 420 can be specifically used for: determining reflectivity, differential reflectivity, cross-correlation coefficient, and differential phase shift rate in the precipitation parameter; determining reflectivity deviation corresponding to the reflectivity and differential phase shift deviation corresponding to the differential phase shift rate according to the multiple reflectivity and differential phase shift rate within the radial distance of the target elevation angle; substituting the numerical values of the reflectivity, differential reflectivity, cross-correlation coefficient, differential phase shift rate, and reflectivity deviation and differential phase shift deviation into the corresponding membership functions respectively to obtain the function values of the membership functions; obtaining the probability value of each precipitation parameter under each precipitation category according to the product of the function value and the corresponding parameter weight value, and adding the probability values of the precipitation parameters to obtain the probability value of the precipitation category.

[0085] In the embodiment of the present application, the category determination module 430 can be specifically used for: determining multiple precipitation categories corresponding to the target elevation angle, the elevation angle height, and the bottom height and the top height of the zero-degree layer height; comparing the elevation angle height and the bottom height to obtain a comparison result; if the comparison result is that the elevation angle height is greater than the bottom height, determining the numerical size of the feature value corresponding to the reflectivity echo feature and the preset threshold value; if the feature value is less than the preset threshold value, determining that the multiple precipitation categories corresponding to the target elevation angle do not include mixed precipitation; if the feature value is not less than the preset threshold value, determining that the multiple precipitation categories corresponding to the target elevation angle do not include liquid precipitation; comparing the elevation angle height and the top height to obtain a comparison result; if the comparison result is that the elevation angle height is less than the top height, determining that the multiple precipitation categories corresponding to the target elevation angle do not include solid precipitation; determining the target probability value with the maximum value in the precipitation categories corresponding to the target elevation angle according to the probability value, and determining the precipitation category corresponding to the target probability value as the initial precipitation category; determining multiple initial precipitation categories within the radial distance of the target elevation angle, and performing continuity detection on each initial precipitation category to obtain a detection result; if the detection result is that the categories corresponding to the initial precipitation category and the two initial precipitation categories before and after the initial precipitation category are the same, and the categories corresponding to the initial precipitation category and the two initial precipitation categories before and after the initial precipitation category are not the same, adjusting the category corresponding to the initial precipitation category to the categories corresponding to the two initial precipitation categories before and after the initial precipitation category to obtain the target precipitation category. If the detection result is that the categories corresponding to the two initial precipitation categories in the radial distance adjacent to the initial precipitation category are the same, and the category corresponding to the initial precipitation category is not the same as the categories corresponding to the two initial precipitation categories, the category corresponding to the initial precipitation category is adjusted to the categories corresponding to the two initial precipitation categories before and after the initial precipitation category, to obtain the target precipitation category.

[0086] In the embodiments of the present application, the substitution module 440 can also be specifically used for: determining the differential phase shift rate, reflectivity, differential reflectivity, precipitation quantity value, and empirical coefficient in the precipitation parameters; determining the first precipitation rule according to the empirical coefficient, reflectivity, and precipitation quantity value; determining the second precipitation rule according to the empirical coefficient, differential phase shift rate, and precipitation quantity value; determining the third precipitation rule according to the empirical coefficient, reflectivity, differential reflectivity, and precipitation quantity value; determining the fourth precipitation rule according to the empirical coefficient, reflectivity, differential phase shift rate, and precipitation quantity value; determining the preset precipitation rule according to the first precipitation rule, second precipitation rule, third precipitation rule, and fourth precipitation rule; determining the precipitation rule corresponding to the target precipitation category from the preset precipitation rule according to the plurality of precipitation parameters.

[0087] In the embodiments of the present application, the substitution module 440 can also be specifically used for: determining the threshold values corresponding to the target precipitation category, reflectivity, and differential reflectivity, respectively; If the target precipitation category is liquid precipitation, comparing the differential phase shift rate and the preset phase shift threshold value, the reflectivity and the corresponding threshold value, and the differential reflectivity and the corresponding threshold value, to obtain the first comparison result; If the target precipitation category is mixed precipitation, comparing the differential phase shift rate and the preset phase shift threshold value to obtain the second comparison result; wherein: If the first comparison result is that the differential phase shift rate is greater than the preset phase shift threshold value, and the reflectivity and the differential reflectivity are both greater than the corresponding threshold value, the precipitation rule corresponding to the target precipitation category is determined to be the fourth precipitation rule; If the first comparison result is that the differential phase shift rate is greater than the preset phase shift threshold value and the reflectivity is greater than the corresponding threshold value, and the differential reflectivity is not greater than the corresponding threshold value, the precipitation rule corresponding to the target precipitation category is determined to be the second precipitation rule; If the first comparison result is that the differential phase shift rate is not greater than the preset phase shift threshold value or the reflectivity is not greater than the corresponding threshold value, the comparison result of the differential reflectivity and the corresponding threshold value is determined; When the comparison result of the differential reflectivity and the corresponding threshold value is that the differential reflectivity is greater than the threshold value, it is determined that the precipitation rule corresponding to the target precipitation category is the third precipitation rule; When the comparison result of the differential reflectivity and the corresponding threshold value is that the differential reflectivity is not greater than the threshold value, the precipitation rule corresponding to the target precipitation category is determined to be the first precipitation rule; in: If the second comparison result is that the differential phase shift rate is greater than the preset phase shift threshold, the precipitation rule corresponding to the target precipitation category is determined to be the second precipitation rule; If the second comparison result is that the differential phase shift rate is not greater than the preset phase shift threshold, it is determined that the precipitation value corresponding to the lowest elevation angle is zero.

[0088] Figure 5 A schematic diagram of the structure of a device for performing a precipitation measurement method based on hybrid scanning data according to an embodiment of the present application is provided in the embodiment of the present application. Figure 5 As shown, the device 500 includes: The device 500 may include one or more processors 501 , one or more computer-readable storage media memories 502 , a communication component 503 , and other components. The processor 501 , the memory 502 , and the communication component 503 are connected via a bus 504 .

[0089] In a specific implementation process, at least one processor 501 executes the computer-executable instructions stored in the memory 502, so that the at least one processor 501 performs the above precipitation measurement method based on hybrid scanning data.

[0090] The specific implementation process of the processor 501 can be found in the above method embodiment. Its implementation principle and technical effects are similar and will not be repeated here in this embodiment.

[0091] Furthermore, the processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), or application-specific integrated circuits (ASICs). A general-purpose processor may be a microprocessor or any conventional processor. The steps of the method disclosed in this application may be directly executed by a hardware processor or by a combination of hardware and software modules within the processor.

[0092] The memory can include a random access memory (RAM) and can also include a non-volatile memory (NVM), such as at least one disk memory.

[0093] The bus can be an industry standard architecture (ISA) bus, a peripheral component (PCI) bus, an extended industry standard architecture (EISA) bus, or the like. The bus can be divided into an address bus, a data bus, a control bus, and the like. For ease of representation, the bus in the drawings of the present application does not limit to only one bus or one type of bus.

[0094] In some embodiments, a computer program product is also provided, including a computer program or instructions, which, when executed by a processor, implement the steps of any of the above-mentioned precipitation measurement methods based on mixed scanning data.

[0095] The specific implementation of each of the above operations can refer to the previous embodiments, which will not be repeated here.

[0096] Those of ordinary skill in the art can understand that all or part of the steps of the various methods of the above embodiments can be completed by instructions, or by relevant hardware controlled by the instructions, which can be stored in a computer readable storage medium and loaded and executed by a processor.

[0097] To this end, an embodiment of the present application provides a computer readable storage medium, which stores a plurality of program codes. The program codes can be loaded by a processor to execute the steps of any of the precipitation measurement methods based on mixed scanning data provided by the embodiments of the present application.

[0098] The storage medium can include a read only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and the like.

[0099] According to an aspect of the present application, a computer program product or a computer program is provided, which includes computer instructions stored in a computer readable storage medium.

[0100] Since the instructions stored in the storage medium can execute the steps in any one of the precipitation measurement methods based on mixed scanning data provided by the embodiments of the present application, the beneficial effects that can be achieved by any one of the precipitation measurement methods based on mixed scanning data provided by the embodiments of the present application can be achieved, which will be described in detail in the foregoing embodiments, and will not be described here again.

[0101] Other embodiments of the application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. It is intended that the specification and examples be considered as exemplary only, with the true scope and spirit of the application being indicated by the following claims.

[0102] It should be understood that the application is not limited to the precise construction that has been described above and shown in the accompanying drawings, and that various modifications and changes can be made by those skilled in the art without departing from the scope of the application.

Claims

1. A precipitation measurement method based on hybrid scanning data, characterized in that: The method comprises: Acquire radar data based on a dual-polarization radar, and determine a target elevation angle and its corresponding target radar data based on reflectivity echo characteristics and corresponding thresholds at multiple elevation angles corresponding to each azimuth angle in the radar data, where the target elevation angle is the lowest unobstructed elevation angle corresponding to each azimuth angle; Determining a plurality of precipitation parameters in the target radar data and membership functions under a plurality of precipitation categories, and determining a probability value of the precipitation category based on the membership functions and parameter weight values ​​of each precipitation parameter under each precipitation category; Determining a target precipitation category from the plurality of precipitation categories according to the probability value, the zero-degree layer height, a preset threshold, and continuity detection; According to the multiple precipitation parameters, a precipitation rule corresponding to the target precipitation category is determined from preset precipitation rules, and the corresponding precipitation parameters are substituted into the precipitation rule to obtain a precipitation amount value corresponding to the target radar data.

2. The method according to claim 1, characterized in that The dual-polarization radar-based method of acquiring radar data and determining a target elevation angle and corresponding target radar data based on reflectivity echo characteristics and corresponding thresholds at multiple elevation angles corresponding to each azimuth angle in the radar data includes: determining a first threshold value and a second threshold value among the threshold values; determining the reflectivity echo feature greater than the first threshold as a first target reflectivity echo feature, and determining the reflectivity echo feature greater than the second threshold as a second target reflectivity echo feature, wherein the value of the second threshold is greater than the value of the first threshold; Determining an initial elevation angle and a characteristic value corresponding to the first target reflectivity echo feature, and determining a difference between the characteristic values ​​of any two adjacent initial elevation angles according to an order of magnitude of the initial elevation angles; Determining the number of the differences greater than a preset difference threshold as the target reflection difference number; Determining the number of second target reflections corresponding to the second target reflectivity echo feature, and if the number of second target reflections is greater than a preset number threshold, determining the number of the initial elevation angle corresponding to the first target reflectivity echo feature as the number of target reflections; The target elevation angle is determined according to the target reflection difference quantity and the target reflection quantity.

3. The method according to claim 2, characterized in that The determining the target elevation angle according to the target reflection difference quantity and the target reflection quantity includes: Determining, according to a plurality of data acquisition moments of the dual-polarization radar and the radar data corresponding to the data acquisition moments, the number of target reflection differences and the number of target reflections corresponding to each of the data acquisition moments; Determining a sum of the target reflection difference values ​​and the sum of the target reflection values ​​corresponding to all the data acquisition moments, and determining an elevation angle division value corresponding to each of the initial elevation angles at each azimuth angle based on a division value between the sum of the target reflection difference values ​​and the sum of the target reflection values; According to the angle order, starting from the initial elevation angle with the largest angle, traverse each initial elevation angle and its corresponding subsequent initial elevation angle in sequence; If the elevation angle division value corresponding to the initial elevation angle is greater than a preset elevation angle threshold, and the elevation angle division value of the subsequent initial elevation angle is less than the preset elevation angle threshold, the initial elevation angle is determined to be the target elevation angle.

4. The method according to claim 1, wherein Determining a plurality of precipitation parameters in the target radar data and membership functions under a plurality of precipitation categories, and determining a probability value of the precipitation category based on the membership functions and parameter weight values ​​of each precipitation parameter under each precipitation category, includes: Determining the reflectivity, differential reflectivity, cross-correlation coefficient, and differential phase shift rate among the precipitation parameters; Determining, according to a plurality of the reflectivities and the differential phase shift rates at the target elevation angle within a radial distance, a reflectivity deviation corresponding to the reflectivity and a differential phase shift deviation corresponding to the differential phase shift rate; Substituting the values ​​of the reflectivity, the differential reflectivity, the mutual correlation coefficient, the differential phase shift rate, and the reflectivity deviation and the differential phase shift deviation into the corresponding membership functions to obtain function values ​​of the membership functions; According to the multiplication of the function value and the corresponding parameter weight value, the probability value of each precipitation parameter under each precipitation category is obtained, and the probability value of each precipitation parameter is added to obtain the probability value of the precipitation category.

5. The method according to claim 1, wherein Determining a target precipitation category from the plurality of precipitation categories based on the probability value, the zero-degree layer height, a preset threshold, and continuity detection includes: Determining a plurality of precipitation categories, elevation heights, and bottom heights and top heights of the zero-degree layer height corresponding to the target elevation angle; Comparing the elevation angle height and the bottom height to obtain a comparison result; If the comparison result is that the elevation angle height is greater than the bottom height, determining the numerical value of the characteristic value corresponding to the reflectivity echo feature and the preset threshold; If the characteristic value is less than the preset threshold, determining that the multiple precipitation categories corresponding to the target elevation angle do not include mixed precipitation; If the characteristic value is not less than the preset threshold, determining that the multiple precipitation categories corresponding to the target elevation angle do not include liquid precipitation; Comparing the elevation angle height and the top height to obtain a comparison result; If the comparison result is that the elevation angle height is less than the top height, determining that the multiple precipitation categories corresponding to the target elevation angle do not include solid precipitation; Determining, based on the probability values, a target probability value having the largest value among the precipitation categories corresponding to the target elevation angle, and determining the precipitation category corresponding to the target probability value as the initial precipitation category; determining a plurality of the initial precipitation categories within a radial distance of the target elevation angle, and performing the continuity test on each of the initial precipitation categories to obtain a test result; If the detection result shows that the categories corresponding to the two initial precipitation categories before and after the initial precipitation category are the same, and the initial precipitation category is different from the categories corresponding to the two initial precipitation categories before and after, then adjusting the category corresponding to the initial precipitation category to the category corresponding to the two initial precipitation categories before and after to obtain the target precipitation category; If the detection result shows that the categories corresponding to the two initial precipitation categories on adjacent radial directions at the same radial distance are the same, and the initial precipitation category is different from the categories corresponding to the two initial precipitation categories on the adjacent radial directions, then the category corresponding to the initial precipitation category is adjusted to the category corresponding to the two initial precipitation categories on the adjacent radial directions to obtain the target precipitation category.

6. The method according to claim 1, characterized in that The step of determining a precipitation rule corresponding to the target precipitation category from preset precipitation rules based on the multiple precipitation parameters, and substituting the corresponding precipitation parameters into the precipitation rule to obtain a precipitation amount value corresponding to the target radar data includes: Determining the differential phase shift rate, the reflectivity, the differential reflectivity, the precipitation value, and the empirical coefficient among the precipitation parameters; Determining a first precipitation rule according to the empirical coefficient, the reflectivity, and the precipitation value; Determining a second precipitation rule according to the empirical coefficient, the differential phase shift rate, and the precipitation value; determining a third precipitation rule according to the empirical coefficient, the reflectivity, the differential reflectivity, and the precipitation value; Determining a fourth precipitation rule according to the empirical coefficient, the reflectivity, the differential phase shift rate, and the precipitation value; Determining the preset precipitation rule according to the first precipitation rule, the second precipitation rule, the third precipitation rule, and the fourth precipitation rule; According to the multiple precipitation parameters, a precipitation rule corresponding to the target precipitation category is determined from the preset precipitation rules.

7. The method according to claim 6, characterized in that Determining the precipitation rule corresponding to the target precipitation category from the preset precipitation rules based on the multiple precipitation parameters includes: Determining thresholds corresponding to the target precipitation category, the reflectivity, and the differential reflectivity; If the target precipitation category is liquid precipitation, comparing the differential phase shift rate with the preset phase shift threshold, the reflectivity with the corresponding threshold, and the differential reflectivity with the corresponding threshold to obtain a first comparison result; If the target precipitation category is mixed precipitation, comparing the differential phase shift rate with the preset phase shift threshold to obtain a second comparison result; in: If the first comparison result is that the differential phase shift rate is greater than the preset phase shift threshold, and both the reflectivity and the differential reflectivity are greater than the corresponding thresholds, determining that the precipitation rule corresponding to the target precipitation category is the fourth precipitation rule; If the first comparison result is that the differential phase shift rate is greater than the preset phase shift threshold and the reflectivity is greater than the corresponding threshold, and the differential reflectivity is not greater than the corresponding threshold, determining that the precipitation rule corresponding to the target precipitation category is the second precipitation rule; If the first comparison result is that the differential phase shift rate is not greater than the preset phase shift threshold or the reflectivity is not greater than the corresponding threshold, determining a comparison result between the differential reflectivity and the corresponding threshold; When the comparison result of the differential reflectivity and the corresponding threshold value is that the differential reflectivity is greater than the threshold value, determining that the precipitation rule corresponding to the target precipitation category is the third precipitation rule; When a comparison result of the differential reflectivity and the corresponding threshold value shows that the differential reflectivity is not greater than the threshold value, determining that the precipitation rule corresponding to the target precipitation category is the first precipitation rule; in: If the second comparison result is that the differential phase shift rate is greater than the preset phase shift threshold, determining that the precipitation rule corresponding to the target precipitation category is the second precipitation rule; If the second comparison result is that the differential phase shift rate is not greater than the preset phase shift threshold, it is determined that the precipitation value corresponding to the lowest elevation angle is zero.

8. A precipitation measurement device based on hybrid scanning data, characterized in that: The device comprises: an acquisition module, configured to acquire radar data based on a dual-polarization radar, and determine a target elevation angle and corresponding target radar data based on reflectivity echo characteristics and corresponding thresholds at multiple elevation angles corresponding to each azimuth angle in the radar data, wherein the target elevation angle is the lowest unobstructed elevation angle corresponding to each azimuth angle; a probability value determination module, configured to determine a plurality of precipitation parameters in the target radar data and membership functions under a plurality of precipitation categories, and determine a probability value of the precipitation category based on the membership functions and parameter weight values ​​of the respective precipitation parameters under each precipitation category; a category determination module, configured to determine a target precipitation category from the plurality of precipitation categories based on the probability value, the zero-degree layer height, a preset threshold, and continuity detection; The substitution module is used to determine the precipitation rule corresponding to the target precipitation category from the preset precipitation rules according to the multiple precipitation parameters, and substitute the corresponding precipitation parameters into the precipitation rule to obtain the precipitation value corresponding to the target radar data.

9. A device, characterized in that include: one or more processors; Memory; One or more programs, wherein the one or more programs are stored in a memory and configured to be executed by one or more processors, the one or more programs being configured to perform the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores program codes, which can be called by a processor to execute the method according to any one of claims 1 to 7.

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