A method and system for wind shear and shear line identification based on laser radar

Abstract

The present invention discloses a method and system for identifying wind shear and shear lines based on laser radar in the field of radar detection technology. The method includes identifying all wind shear slopes from a single radial wind speed data, and screening stronger wind shear slopes according to the wind shear intensity factor; calculating the total wind shear value of each wind shear slope, and comparing it with the wind shear grade criterion to identify the wind shear slope of the strong wind shear grade. All radial wind speed data are extracted from the radar echo signal of the target area to obtain the significant wind shear slopes in the entire target area. According to the position coordinates of the shear points of each wind shear slope, all wind shear slope shear points are clustered and analyzed to form multiple clusters. The clusters that meet the shear line conditions are screened to perform curve fitting to obtain all shear lines. The present invention can effectively identify the position and intensity of wind shear in the target area, and at the same time realize real-time identification and early warning of shear lines, thereby improving the timeliness and accuracy of weather detection and early warning.

Description

Technical Field

[0001] The invention relates to a wind shear and shear line identification method and system based on laser radar, belonging to the technical field of radar detection. Background Art

[0002] In the field of meteorology, wind shear refers to discontinuous changes in wind speed or direction in space, usually in the vertical or horizontal direction; and the shear line generally refers to a narrow and long area where wind speed and wind direction change dramatically, ranging in length from tens to thousands of kilometers. Wind shear is sudden and uncertain, and is often accompanied by severe weather such as thunderstorms and fronts. In particular, low-altitude wind shear is a major risk factor for aircraft takeoff and landing. Therefore, in weather detection and warning, the identification of wind shear is particularly important. Effective wind shear warning is of great significance for ensuring personnel safety, reducing property losses and improving the accuracy of weather forecasts.

[0003] In existing technologies, wind shear can be identified through surface anemometers and lidars; in the past, shear line identification was mostly based on manual identification of weather maps or identification based on artificial intelligence training models. Manual identification is subjective and requires a lot of work to analyze data; training models require a lot of computing resources, including high-performance hardware and long-term calculations. Deep learning models usually lack transparency and it is difficult to explain their internal decision-making process, which leads to meteorological experts' distrust of their predictions.

[0004] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgement or any form of suggestion that the information constitutes the prior art already known to ordinary technicians in this field. Summary of the invention

[0005] The technical problem to be solved by the present invention is: how to effectively identify the location and intensity of wind shear in the target area, and at the same time realize real-time identification and early warning of the shear line, so as to improve the timeliness and accuracy of weather detection and early warning.

[0006] In order to solve the above technical problems, the present invention is implemented by adopting the following technical solutions.

[0007] In a first aspect, the present invention provides a method for identifying wind shear and shear line based on laser radar, comprising:

[0008] Extract a single radial wind speed data from the radar echo signal of the target area;

[0009] identifying all wind shear slopes in the radial direction from the single radial wind speed data to obtain a wind shear slope set;

[0010] According to the wind shear intensity factor, a plurality of wind shear slopes having wind shear intensity factor values ​​exceeding a set threshold are screened from the wind shear slope set, and a plurality of wind shear slopes having larger wind shear intensity factor values ​​are extracted to obtain a relatively strong wind shear slope set;

[0011] The total wind shear value of each wind shear slope in the strong wind shear slope set is calculated respectively, and the level of each wind shear slope in the relatively strong wind shear slope set is evaluated according to a preset wind shear level criterion, so as to identify the wind shear slope of the strong wind shear level;

[0012] Extract all radial wind speed data from the radar echo signal in the target area, repeat the above steps to obtain a set of significant wind shear slopes in the entire target area;

[0013] According to the position coordinates of each wind shear slope shear point in the significant wind shear slope set, cluster analysis is performed on all wind shear slope shear points to form a plurality of clusters containing wind shear slope shear points, including:

[0014] (1) Convert the position coordinates of all wind shear slope shear points into Cartesian coordinates;

[0015] (2) Selecting the Cartesian coordinates of any wind shear slope shear point as the center of a circle, drawing a circular area with the preset minimum distance between two wind shear slope shear points as the radius, and traversing the remaining wind shear slope shear points within the circular area using the Euclidean distance formula;

[0016] (3) Determine whether each remaining wind shear slope shear point falls within the current circular area. If a remaining wind shear slope shear point falls within the current circular area:

[0017] When the Euclidean distance between the center of the circle and the wind shear slope shear point falling within the current circular area is less than or equal to a preset minimum distance between two wind shear slope shear points, the wind shear slope shear point falling within the current circular area and the wind shear slope shear point serving as the current center of the circle are clustered into one cluster;

[0018] (4) updating the position coordinates of the center of the circle to the position coordinates of the wind shear slope shear point falling within the circular area, drawing a new circular area with the preset minimum distance between two wind shear slope shear points as the radius, traversing the remaining wind shear slope shear points within the new circular area using the Euclidean distance formula to obtain a cluster containing wind shear slope shear points, and recording the total number of wind shear slope shear points in the cluster containing wind shear slope shear points, and at the same time estimating the length of the shear line according to the distance formula;

[0019] (5) Determine whether the total number of shear points on the wind shear slope and the estimated length of the shear line meet the fitting shear line conditions:

[0020] When the total number of wind shear slope shear points and the estimated length of the shear line do not meet the fitting shear line condition, all wind shear slope shear points in the cluster containing the wind shear slope shear points are removed, and the process returns to step (2) to reselect wind shear slope shear points for cluster analysis;

[0021] (6) Eliminate the clustered wind shear slope shear point clusters, and repeat steps (2) to (5) based on the currently unclustered wind shear slope shear points until all wind shear slope shear points are clustered, thereby obtaining multiple clusters containing wind shear slope shear points in the target area;

[0022] According to the multiple clusters containing wind shear slope shear points, clusters that meet the shear line conditions are screened out for curve fitting to obtain all shear lines in the target area, that is, when the total number of wind shear slope shear points and the estimated length of the shear line meet the fitting shear line conditions, all wind shear slope shear points in the cluster containing the wind shear slope shear points are sorted from small to large according to azimuth in a Cartesian coordinate system, and fitting is performed according to a polynomial curve to obtain a shear line, thereby obtaining all shear lines in the target area.

[0023] Furthermore, before identifying all wind shear slopes in the radial direction from the single radial wind speed data, the method further includes preprocessing the single radial wind speed data using a smoothing formula to eliminate invalid data and isolated data.

[0024] Further, all wind shear slopes in the radial direction are identified from the single radial wind speed data to obtain a wind shear slope set, including:

[0025] The detection length of the wind shear slope is changed cyclically, and the speed difference of the wind speed data at the start and end points of each wind shear slope is calculated using a single slope formula at each wind shear slope detection length;

[0026] Based on the speed difference between the wind speed data at the start and end points of each wind shear slope, and according to a preset wind shear determination standard, all wind shear slopes meeting the conditions in the radial wind speed data are identified;

[0027] The position coordinates of all wind shear slopes that meet the conditions are recorded to obtain a wind shear slope set.

[0028] Further, according to the wind shear intensity factor, several wind shear slopes whose wind shear intensity factor values ​​exceed a set threshold are screened from the wind shear slope set, and several wind shear slopes with larger wind shear intensity factor values ​​are extracted to obtain a relatively strong wind shear slope set, including:

[0029] Using the wind shear intensity factor to evaluate the intensity of each wind shear slope in the wind shear slope set, to obtain intensity factor values ​​of all wind shear slopes;

[0030] One or more thresholds are preset for distinguishing between a strong wind shear slope and a weak wind shear slope.

[0031] Comparing the intensity factor values ​​of all wind shear slopes with the threshold value, and extracting a number of wind shear slopes whose wind shear intensity factor values ​​exceed the set threshold value;

[0032] Among the several wind shear slopes whose wind shear intensity factor values ​​exceed a set threshold, several wind shear slopes with larger wind shear intensity factor values ​​are extracted to obtain a set of stronger wind shear slopes.

[0033] Furthermore, the method for calculating the total wind shear value of the wind shear slope includes:

[0034] Based on the wind speed, position and length of the wind shear slope corresponding to the wind shear slope sampling point, the average speed of the wind shear slope is calculated;

[0035] Based on the wind speed and position corresponding to the wind shear slope sampling point, the total wind energy value of the wind shear slope is calculated;

[0036] Calculating a wind speed gradient based on the length of the wind shear slope, the average speed of the wind shear slope, and the total wind energy of the wind shear slope, and determining the sign of the wind speed gradient;

[0037] The total wind shear value of the wind shear slope is calculated based on the wind speed gradient and the length of the wind shear slope.

[0038] Further, when the total wind shear value of the wind shear slope is greater than 0, it indicates that the wind shear slope speed is increasing; when the total wind shear value of the wind shear slope is less than 0, it indicates that the wind shear slope speed is decreasing.

[0039] Furthermore, the method for obtaining the position coordinates of each wind shear slope shear point in the significant wind shear slope set includes:

[0040] (1) According to the definition of wind shear, at each discontinuity of wind direction or wind speed on the wind shear slope, the position coordinates of the wind direction change point on each wind shear slope are recorded as the position coordinates of the shear point on the wind shear slope, that is, starting from the first sampling point of the wind shear slope, hour, ,in, Indicates The wind speed corresponding to the sampling point is Indicates The wind speed corresponding to the sampling point is represents the total number of wind shear slope sampling points, Indicates The position corresponding to the sampling point, Indicates The position corresponding to the sampling point, represents the distance between the wind shear slope shear point and the wind laser radar, , , Indicates Radial wind speed data, , Represents the total number of radial wind speed data. Indicates the first A wind shear slope, , The total number of wind shear slopes representing the strong wind shear level selected in a single radial wind speed data;

[0041] (2) If the wind direction in the wind shear slope does not change, the position coordinates of the starting point of the wind shear slope are recorded as the position coordinates of the shear point of the wind shear slope. That is, there is no sampling point in the wind shear slope that makes If established, ,in, Indicates the position corresponding to the first sampling point;

[0042] (3) According to the radar echo data, the radial azimuth information corresponding to the shear point of the wind shear slope is extracted as the ordinate of the shear point , Indicates the azimuth of the wind shear slope shear point.

[0043] In a second aspect, the present invention provides a laser radar-based wind shear and shear line identification system, including a wind shear identification subsystem and a shear line identification subsystem;

[0044] The wind shear identification subsystem includes the following modules:

[0045] The radial wind speed acquisition module is used to extract a single radial wind speed data from the radar echo signal of the target area;

[0046] A wind shear slope identification module, used to identify all wind shear slopes in the radial direction from the single radial wind speed data to obtain a wind shear slope set;

[0047] A wind shear slope screening module is used to screen a number of wind shear slopes whose wind shear intensity factor values ​​exceed a set threshold from the wind shear slope set according to the wind shear intensity factor, and extract a number of wind shear slopes with larger wind shear intensity factor values ​​to obtain a strong wind shear slope set;

[0048] A wind shear slope evaluation module, used to respectively calculate the total wind shear value of each wind shear slope in the relatively strong wind shear slope set, evaluate the level of each wind shear slope in the relatively strong wind shear slope set according to a preset wind shear level criterion, and identify the wind shear slope of the strong wind shear level;

[0049] The shear line identification subsystem includes the following modules:

[0050] A significant wind shear slope set acquisition module is used to extract all radial wind speed data from the radar echo signal of the target area, repeatedly execute the wind shear identification subsystem, and obtain a significant wind shear slope set in the entire target area;

[0051] A cluster analysis module is used to perform cluster analysis on all wind shear slope shear points according to the position coordinates of each wind shear slope shear point in the significant wind shear slope set to form a plurality of clusters containing wind shear slope shear points, including:

[0052] (1) Convert the position coordinates of all wind shear slope shear points into Cartesian coordinates;

[0053] (2) Selecting the Cartesian coordinates of any wind shear slope shear point as the center of a circle, drawing a circular area with the preset minimum distance between two wind shear slope shear points as the radius, and traversing the remaining wind shear slope shear points within the circular area using the Euclidean distance formula;

[0054] (3) Determine whether each remaining wind shear slope shear point falls within the current circular area. If a remaining wind shear slope shear point falls within the current circular area:

[0055] When the Euclidean distance between the center of the circle and the wind shear slope shear point falling within the current circular area is less than or equal to a preset minimum distance between two wind shear slope shear points, the wind shear slope shear point falling within the current circular area and the wind shear slope shear point serving as the current center of the circle are clustered into one cluster;

[0056] (4) updating the position coordinates of the center of the circle to the position coordinates of the wind shear slope shear point falling within the circular area, drawing a new circular area with the preset minimum distance between two wind shear slope shear points as the radius, traversing the remaining wind shear slope shear points within the new circular area using the Euclidean distance formula to obtain a cluster containing wind shear slope shear points, and recording the total number of wind shear slope shear points in the cluster containing wind shear slope shear points, and at the same time estimating the length of the shear line according to the distance formula;

[0057] (5) Determine whether the total number of shear points on the wind shear slope and the estimated length of the shear line meet the fitting shear line conditions:

[0058] When the total number of wind shear slope shear points and the estimated length of the shear line do not meet the fitting shear line condition, all wind shear slope shear points in the cluster containing the wind shear slope shear points are removed, and the process returns to step (2) to reselect wind shear slope shear points for cluster analysis;

[0059] (6) Eliminate the clustered wind shear slope shear point clusters, and repeat steps (2) to (5) based on the currently unclustered wind shear slope shear points until all wind shear slope shear points are clustered, thereby obtaining multiple clusters containing wind shear slope shear points in the target area;

[0060] The shear line identification module is used to screen out clusters that meet the shear line conditions based on the multiple clusters containing wind shear slope shear points, and perform curve fitting to obtain all shear lines in the target area. That is, when the total number of wind shear slope shear points and the estimated length of the shear line meet the shear line fitting condition, all wind shear slope shear points in the cluster containing the wind shear slope shear points are sorted from small to large according to azimuth in a Cartesian coordinate system, and fit according to a polynomial curve to obtain a shear line, thereby obtaining all shear lines in the target area.

[0061] Compared with the prior art, the present invention has the following beneficial effects:

[0062] 1. The present invention can accurately obtain wind speed change information in the target area by extracting a single radial wind speed data from the radar echo signal of the target area. The present invention also identifies all wind shear slopes from a single radial wind speed data to form a wind shear slope set, which can capture all possible wind shear phenomena in the target area, avoid missed detection, and improve the comprehensiveness of identification;

[0063] 2. The present invention selects several wind shear slopes whose wind shear intensity factor values ​​exceed a set threshold value according to the wind shear intensity factor, and extracts several wind shear slopes with larger wind shear intensity factor values ​​to form a strong wind shear slope set, thereby excluding wind shear phenomena with weaker intensity and less impact on flight safety, and focusing on strong wind shear that poses a greater threat to flight safety, thereby improving the pertinence and effectiveness of identification;

[0064] 3. The present invention also compares the total wind shear value of each wind shear slope in the strong wind shear slope set with the preset wind shear level criterion, accurately judges the intensity level of wind shear, identifies the wind shear slope of the strong wind shear level and issues an early warning, so that relevant personnel can take countermeasures in time, avoid flight accidents caused by wind shear, and improve the timeliness and accuracy of weather detection and early warning;

[0065] 4. The present invention also extracts all radial wind speed data in the target area, identifies significant wind shear slopes, and clusters and analyzes the shear point locations to form multiple clusters containing shear points of wind shear slopes. Clusters that meet the shear line conditions are further screened for curve fitting to accurately depict the shear line. This method improves the comprehensive monitoring and early warning capabilities of wind shear in the entire target area, ensures flight safety, and significantly enhances the timeliness and accuracy of weather warnings. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Figure 1 is a flow chart of a laser radar-based wind shear identification method provided in an embodiment of the present invention;

[0067] Figure 2 is a flow chart of a shear line recognition method based on laser radar provided in an embodiment of the present invention;

[0068] Figure 3 It is a schematic diagram of the module architecture of a wind shear and shear line identification system based on laser radar provided in an embodiment of the present invention;

[0069] Figure 4 is a detailed flow chart of a shear line recognition method based on laser radar provided in an embodiment of the present invention;

[0070] Figure 5 It is a schematic diagram of the effect of identifying wind shear and shear line under convective weather conditions provided by an embodiment of the present invention;

[0071] Figure 6 It is a schematic diagram of the effect of identifying wind shear and shear line in gusty weather conditions provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0072] The technical solution of the present invention is described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present invention and the specific features in the embodiments are detailed descriptions of the technical solution of the present invention, rather than limitations on the technical solution of the present invention. The embodiments of the present invention and the technical features in the embodiments may be combined with each other unless there is a conflict.

[0073] The term "and / or" is only a description of the association relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " generally indicates that the related objects are in an "or" relationship.

[0074] Example 1

[0075] like Figure 1 As shown, this embodiment introduces a wind shear identification method based on laser radar, including the following steps:

[0076] Step 1: Extract a single radial wind speed data from the radar echo signal in the target area.

[0077] Before identifying all wind shear slopes in the radial direction from the single radial wind speed data, the method further includes preprocessing the single radial wind speed data using a smoothing formula to eliminate invalid data and isolated data.

[0078] In this embodiment, the smoothing formula is expressed as:

[0079] (1);

[0080] In the formula, Represents the original wind speed profile group The data points, Represents the original wind speed profile group The data points, Represents the original wind speed profile group The data points, represents the total number of valid data points, Represents the reorganized wind speed profile group obtained after smoothing formula processing No. data points.

[0081] Step 2: Identify all wind shear slopes in the radial direction from the single radial wind speed data to obtain a wind shear slope set ,include:

[0082] Cyclic change of wind shear ramp detection length , using the single slope formula to calculate the velocity difference of wind speed data at each detection length of the wind shear slope ;

[0083] In this embodiment, the single slope formula is as follows:

[0084] (2);

[0085] In the formula, represents the distance between the sampling data point and the laser radar, represents the wind shear slope detection length, Indicates that the distance between the sampling data point and the laser radar is , the wind shear slope detection length is The slope end velocity of the wind shear slope at time , Indicates the slope starting speed of the wind shear slope.

[0086] Based on the velocity difference between adjacent points in the wind speed data at each detection length of the wind shear slope , according to a preset wind shear determination standard, all wind shear slopes meeting the conditions in the radial wind speed data are identified, wherein the preset wind shear determination standard is expressed as:

[0087] (3);

[0088] Wherein, threshold A represents the minimum speed difference that satisfies the wind shear condition.

[0089] In this embodiment, the preset wind shear determination standard is expressed as:

[0090] (4);

[0091] Record the position coordinates of all wind shear slopes that meet the conditions and obtain the wind shear slope set .

[0092] Step 3: Based on the wind shear intensity factor, the wind shear slope set The wind shear slopes with wind shear intensity factor values ​​exceeding the set threshold are screened, and the wind shear slopes with larger wind shear intensity factor values ​​are extracted to obtain the strong wind shear slope set. ,include:

[0093] Using wind shear intensity factor Evaluate the wind shear slope ensemble The intensity of each wind shear slope in is obtained to obtain the intensity factor value of all wind shear slopes;

[0094] One or more thresholds are preset to distinguish between a strong wind shear slope and a weak wind shear slope, wherein one of the preset thresholds is expressed as:

[0095] (5);

[0096] Wherein, threshold B represents the minimum wind shear intensity factor value that meets the strong wind shear condition.

[0097] In this embodiment, the preset threshold for distinguishing a strong wind shear slope from a weak wind shear slope is expressed as:

[0098] (6);

[0099] Comparing the intensity factor values ​​of all wind shear slopes with the threshold value, and extracting a number of wind shear slopes whose wind shear intensity factor values ​​exceed the set threshold value;

[0100] Among the wind shear slopes whose wind shear intensity factor values ​​exceed the set threshold, several wind shear slopes with larger wind shear intensity factor values ​​are extracted to obtain a set of stronger wind shear slopes. .

[0101] In this embodiment, the first four wind shear slopes with larger intensity factor values ​​are extracted.

[0102] Step 4: Calculate the total wind shear value of each wind shear slope in the strong wind shear slope set and compared with the preset wind shear level criteria to identify the wind shear slope of strong wind shear level.

[0103] In this embodiment, the total wind shear value of the wind shear slope is The calculation methods include:

[0104] Based on the wind speed, position and length of the wind shear slope corresponding to the wind shear slope sampling point, the average speed of the wind shear slope is calculated, where the average speed of the wind shear slope is expressed as:

[0105] (1);

[0106] In the formula, represents the average speed of the wind shear slope, represents the total number of wind shear slope sampling points, Indicates The wind speed corresponding to the sampling point is Indicates The wind speed corresponding to the sampling point is Indicates The position corresponding to the sampling point, Indicates The position corresponding to the sampling point, represents the length of the wind shear slope, , Indicates The position corresponding to the sampling point, Represents the position corresponding to the first sampling point, where .

[0107] Based on the wind speed and position corresponding to the wind shear slope sampling point, the total wind energy value of the wind shear slope is calculated, where the total wind energy value of the wind shear slope is expressed as:

[0108] (2);

[0109] In the formula, Represents the total wind energy of the wind shear slope.

[0110] Based on the length of the wind shear slope, the average speed of the wind shear slope and the total wind energy of the wind shear slope, the wind speed gradient is calculated, and the sign of the wind speed gradient is determined, wherein the wind speed gradient is expressed as:

[0111] (3);

[0112] In the formula, Represents the wind speed gradient.

[0113] In this embodiment, the first intermediate variable and the second intermediate variable are introduced Determine the sign of the wind speed gradient, wherein the first intermediate variable and the second intermediate variable have no practical meaning;

[0114] (4);

[0115] According to the first intermediate variable and the second intermediate variable , the method for determining the sign of the wind speed gradient is expressed as:

[0116] (5);

[0117] The total wind shear value of the wind shear slope is calculated based on the wind speed gradient and the length of the wind shear slope.

[0118] (6);

[0119] In the formula, The total wind shear value representing the wind shear slope.

[0120] When the total wind shear value of the wind shear slope is greater than 0, it indicates that the wind shear slope speed is increasing; when the total wind shear value of the wind shear slope is less than 0, it indicates that the wind shear slope speed is decreasing.

[0121] Wherein, the preset wind shear level criterion is expressed as:

[0122] (7);

[0123] Wherein, threshold C represents the critical value of the total wind shear value of the mild wind shear slope, and threshold D represents the critical value of the total wind shear value of the severe wind shear slope.

[0124] In this embodiment, the preset wind shear level criterion is expressed as:

[0125] (8);

[0126] Step 5: Issue an early warning based on the wind shear slope of the strong wind shear level.

[0127] Example 2

[0128] Based on the same inventive concept as Example 1, this example introduces a shear line recognition method based on laser radar, such as Figure 2 and Figure 4 As shown, the specific steps include:

[0129] Step 1: Extract all radial wind speed data from the radar echo signal in the target area, and repeat the steps of the method described in Example 1 to obtain a set of significant wind shear slopes in the entire target area. .

[0130] Obtain the significant wind shear slope set in the entire target area Afterwards, record the significant wind shear slope ensemble The location of each wind shear slope shear point in the.

[0131] In this embodiment, the method for obtaining the position coordinates of each wind shear slope shear point in the significant wind shear slope set includes:

[0132] (1) According to the definition of wind shear, at each discontinuity of wind direction or wind speed on the wind shear slope, the position coordinates of the wind direction change point on each wind shear slope are recorded as the position coordinates of the shear point on the wind shear slope, that is, starting from the first sampling point of the wind shear slope, hour, ,in, Indicates The wind speed corresponding to the sampling point is Indicates The wind speed corresponding to the sampling point is represents the total number of wind shear slope sampling points, Indicates The position corresponding to the sampling point, Indicates The position corresponding to the sampling point, , represents the distance between the wind shear slope shear point and the wind laser radar, , Indicates Radial wind speed data, , Represents the total number of radial wind speed data. Indicates the first A wind shear slope, , The total number of wind shear slopes representing the strong wind shear level selected in a single radial wind speed data;

[0133] (2) If the wind direction in the wind shear slope does not change, the position coordinates of the starting point of the wind shear slope are recorded as the position coordinates of the shear point of the wind shear slope. That is, there is no sampling point in the wind shear slope that makes If established, ,in, Indicates the position corresponding to the first sampling point;

[0134] (3) According to the radar echo data, the radial azimuth information corresponding to the shear point of the wind shear slope is extracted as the ordinate of the shear point , Indicates the azimuth of the wind shear slope shear point.

[0135] Step 2: According to each wind shear slope shear point in the significant wind shear slope set The location coordinates of the wind shear slope are used to perform cluster analysis on all wind shear slope shear points to form multiple clusters containing wind shear slope shear points. The clusters that meet the shear line conditions are screened out for curve fitting to obtain all shear lines in the target area.

[0136] In this embodiment, a method of performing cluster analysis on all wind shear slope shear points to form a plurality of clusters including wind shear slope shear points includes:

[0137] Step 2.1: Set the position coordinates of all wind shear slope shear points Convert to Cartesian coordinates ,in, Indicates The abscissa of the Cartesian coordinates of the wind shear slope shear point, Indicates The ordinate of the Cartesian coordinate of the wind shear slope shear point, Represents the total number of wind shear slope shear points.

[0138] Step 2.2: Choose a wind shear slope shear point The Cartesian coordinates of the circle are taken as the center, with the minimum distance between the two preset wind shear slope shear points. In the circular area with a radius of , the remaining wind shear slope shear points are traversed using the Euclidean distance formula.

[0139] Wherein, the Euclidean distance formula is expressed as:

[0140] (9);

[0141] In the formula, represents the Euclidean distance between two wind shear slope shear points, Indicates The ordinate of the Cartesian coordinate of the wind shear slope shear point, Indicates The abscissa of the Cartesian coordinates of the wind shear slope shear point, where , .

[0142] Step 2.3: Determine whether each remaining wind shear slope shear point falls within the current circular area. If a remaining wind shear slope shear point falls within the current circular area:

[0143] When the Euclidean distance between the center of the circle and the wind shear slope shear point falling within the circular area Less than or equal to the preset minimum distance between two wind shear slope shear points When , the wind shear slope shear points falling within the current circular area and the wind shear slope shear point as the current circle center are clustered into one cluster.

[0144] in, ;

[0145] Step 2.4: Set the coordinates of the center of the circle Updated to the position coordinates of the wind shear slope shear point falling within the circular area, with the preset minimum distance between two wind shear slope shear points In the new circular area drawn with the radius, the remaining wind shear slope shear points are traversed by the Euclidean distance formula to obtain a cluster containing wind shear slope shear points, and the total number of wind shear slope shear points contained in the cluster containing wind shear slope shear points is recorded. , and the length of the shear line is estimated according to the distance formula, and the estimated length of the shear line is expressed as:

[0146] (10);

[0147] In the formula, represents the estimated length of the shear line, Represents the Cartesian coordinates of the wind shear slope shear point in the cluster containing the wind shear slope shear point The maximum value of Represents the Cartesian coordinates of the wind shear slope shear point in the cluster containing the wind shear slope shear point The minimum value of Represents the Cartesian ordinate of the wind shear slope shear point in the cluster containing the wind shear slope shear point The maximum value of Represents the Cartesian ordinate of the wind shear slope shear point in the cluster containing the wind shear slope shear point The maximum value of Indicates the cluster containing the wind shear slope shear point. Shear points, among which, .

[0148] Step 2.5: Determine whether the total number of wind shear slope shear points and the estimated length of the shear line meet the fitting shear line conditions:

[0149] When the total number of wind shear slope shear points and the estimated length of the shear line do not meet the fitting shear line condition, all wind shear slope shear points in the cluster containing the wind shear slope shear points are removed, and the process returns to step 2.2 to reselect wind shear slope shear points.

[0150] In this embodiment, when the total number of wind shear slope shear points And the estimated length of the shear line When , it is considered that the fitting shear line condition is not met, and all wind shear slope shear points in the cluster are removed. Return to step 2.2 and reselect the wind shear slope shear point as the center to draw a circular area to complete clustering and form multiple clusters containing wind shear slope shear points; otherwise, execute step 2.6.

[0151] When the total number of wind shear slope shear points and the estimated length of the shear line meet the shear line fitting condition, all wind shear slope shear points in the cluster containing the wind shear slope shear points are sorted in ascending azimuth in a Cartesian coordinate system, and fitted according to a polynomial curve to obtain a shear line;

[0152] Among them, the criterion for meeting the shear line condition is expressed as:

[0153] and (1)

[0154] In the formula, Indicates the total number of wind shear slope shear points in a cluster of wind shear slope shear points, the threshold Indicates the total number of minimum wind shear slope shear points for shear line fitting within the cluster, the threshold Represents the minimum fitting length of the shear line fit within the cluster containing the wind shear slope shear point.

[0155] Step 2.6: Eliminate the clustered wind shear slope shear point clusters, and repeat steps 2.1 to 2.5 based on the current unclustered wind shear slope shear points until all wind shear slope shear points are Clustering is completed and all shear lines in the target area are obtained.

[0156] Step 3: Issue an early warning based on the wind shear and shear line identification effect diagram of the target area.

[0157] like Figure 5 The figure shows the effect of using a laser radar-based wind shear and shear line identification method provided by the present invention to identify wind shear and shear line in convective weather conditions; Figure 6 The figure shows the effect of using a laser radar-based wind shear and shear line identification method provided by the present invention to identify wind shear and shear line in gusty conditions. Figure 5 The three renderings and Figure 6 The three renderings in the figure respectively represent the development process of a significant wind shear in the target area under different weather conditions. The red stars in the figure are wind shear centers of different intensities identified by a wind shear and shear line identification method based on laser radar provided by an embodiment of the present invention, where the darker the color, the stronger the wind shear. The red curve is the shear line obtained by identifying the target area using a wind shear and shear line identification method based on laser radar provided by an embodiment of the present invention.

[0158] In practical applications, technicians in related fields can issue early warnings based on the wind shear and shear line recognition effect diagrams in the target area.

[0159] Example 3

[0160] The invention concept is the same as that of other embodiments. This embodiment introduces the second aspect, such as Figure 3 As shown, the present invention provides a laser radar-based wind shear and shear line identification system, including a wind shear identification subsystem and a shear line identification subsystem;

[0161] The wind shear identification subsystem includes the following modules:

[0162] The radial wind speed acquisition module is used to extract a single radial wind speed data from the radar echo signal of the target area;

[0163] A wind shear slope identification module, used to identify all wind shear slopes in the radial direction from the single radial wind speed data to obtain a wind shear slope set;

[0164] A wind shear slope screening module is used to screen a number of wind shear slopes whose wind shear intensity factor values ​​exceed a set threshold from the wind shear slope set according to the wind shear intensity factor, and extract a number of wind shear slopes with larger wind shear intensity factor values ​​to obtain a strong wind shear slope set;

[0165] A wind shear slope evaluation module, used to respectively calculate the total wind shear value of each wind shear slope in the strong wind shear slope set, evaluate the level of each wind shear slope in the relatively strong wind shear slope set according to a preset wind shear level criterion, and identify wind shear slopes of strong wind shear level;

[0166] The shear line identification subsystem includes the following modules:

[0167] A significant wind shear slope set acquisition module is used to extract all radial wind speed data from the radar echo signal of the target area, repeatedly execute the wind shear identification subsystem, and obtain a significant wind shear slope set in the entire target area;

[0168] A cluster analysis module is used to perform cluster analysis on all wind shear slope shear points according to the position coordinates of each wind shear slope shear point in the significant wind shear slope set to form a plurality of clusters containing wind shear slope shear points, including:

[0169] (1) Convert the position coordinates of all wind shear slope shear points into Cartesian coordinates;

[0170] (2) Selecting the Cartesian coordinates of any wind shear slope shear point as the center of a circle, drawing a circular area with the preset minimum distance between two wind shear slope shear points as the radius, and traversing the remaining wind shear slope shear points within the circular area using the Euclidean distance formula;

[0171] (3) Determine whether each remaining wind shear slope shear point falls within the current circular area. If a remaining wind shear slope shear point falls within the current circular area:

[0172] When the Euclidean distance between the center of the circle and the wind shear slope shear point falling within the current circular area is less than or equal to a preset minimum distance between two wind shear slope shear points, the wind shear slope shear point falling within the current circular area and the wind shear slope shear point serving as the current center of the circle are clustered into one cluster;

[0173] (4) updating the position coordinates of the center of the circle to the position coordinates of the wind shear slope shear point falling within the circular area, drawing a new circular area with the preset minimum distance between two wind shear slope shear points as the radius, traversing the remaining wind shear slope shear points within the new circular area using the Euclidean distance formula to obtain a cluster containing wind shear slope shear points, and recording the total number of wind shear slope shear points in the cluster containing wind shear slope shear points, and at the same time estimating the length of the shear line according to the distance formula;

[0174] (5) Determine whether the total number of shear points on the wind shear slope and the estimated length of the shear line meet the fitting shear line conditions:

[0175] When the total number of wind shear slope shear points and the estimated length of the shear line do not meet the fitting shear line condition, all wind shear slope shear points in the cluster containing the wind shear slope shear points are removed, and the process returns to step (2) to reselect wind shear slope shear points for cluster analysis;

[0176] (6) Eliminate the clustered wind shear slope shear point clusters, and repeat steps (2) to (5) based on the currently unclustered wind shear slope shear points until all wind shear slope shear points are clustered, thereby obtaining multiple clusters containing wind shear slope shear points in the target area;

[0177] The shear line identification module is used to screen out clusters that meet the shear line conditions based on the multiple clusters containing wind shear slope shear points, and perform curve fitting to obtain all shear lines in the target area. That is, when the total number of wind shear slope shear points and the estimated length of the shear line meet the shear line fitting condition, all wind shear slope shear points in the cluster containing the wind shear slope shear points are sorted from small to large according to azimuth in a Cartesian coordinate system, and fit according to a polynomial curve to obtain a shear line, thereby obtaining all shear lines in the target area.

[0178] The specific functional implementation of each of the above modules can be found in the relevant contents of the methods of Example 1 and Example 2, which will not be elaborated here.

[0179] In summary, the present invention can accurately obtain wind speed change information in the target area by extracting a single radial wind speed data from the radar echo signal of the target area. The present invention also identifies all wind shear slopes from a single radial wind speed data to form a wind shear slope set, which can capture all possible wind shear phenomena in the target area, avoid missed detection, and improve the comprehensiveness of identification;

[0180] The present invention selects several wind shear slopes whose wind shear intensity factor values ​​exceed a set threshold value according to the wind shear intensity factor, and extracts several wind shear slopes with larger wind shear intensity factor values ​​to form a strong wind shear slope set, thereby excluding wind shear phenomena with weaker intensity and less impact on flight safety, focusing on strong wind shear that poses a greater threat to flight safety, and improving the pertinence and effectiveness of identification;

[0181] The present invention also compares the total wind shear value of each wind shear slope in the strong wind shear slope set with a preset wind shear level criterion, accurately judges the intensity level of wind shear, identifies wind shear slopes of strong wind shear level and issues early warning, so that relevant personnel can take countermeasures in time, avoid flight accidents caused by wind shear, and improve the timeliness and accuracy of weather detection and early warning;

[0182] The present invention also extracts all radial wind speed data in the target area, identifies significant wind shear slopes, and clusters and analyzes the shear point locations to form multiple clusters containing shear points of wind shear slopes. Clusters that meet the shear line conditions are further screened for curve fitting to accurately depict the shear line. This method improves the comprehensive monitoring and early warning capabilities of wind shear in the entire target area, ensures flight safety, and significantly enhances the timeliness and accuracy of weather warnings.

[0183] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0184] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0185] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0186] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0187] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the enlightenment of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the purpose of the present invention and the claims, which all fall within the protection of the present invention.

Claims

1. A method for wind shear and shear line identification based on laser radar, characterized in that: include: Extract a single radial wind speed data from the radar echo signal of the target area; identifying all wind shear slopes in the radial direction from the single radial wind speed data to obtain a wind shear slope set; According to the wind shear intensity factor, a plurality of wind shear slopes having wind shear intensity factor values ​​exceeding a set threshold are screened from the wind shear slope set, and a plurality of wind shear slopes having larger wind shear intensity factor values ​​are extracted to obtain a relatively strong wind shear slope set; The total wind shear value of each wind shear slope in the set of relatively strong wind shear slopes is calculated respectively, and the level of each wind shear slope in the set of relatively strong wind shear slopes is evaluated according to a preset wind shear level criterion, so as to identify the wind shear slopes of the strong wind shear level; Extract all radial wind speed data from the radar echo signal in the target area, repeat the above steps to obtain a set of significant wind shear slopes in the entire target area; According to the position coordinates of each wind shear slope shear point in the significant wind shear slope set, cluster analysis is performed on all wind shear slope shear points to form a plurality of clusters containing wind shear slope shear points, including: (1) Convert the position coordinates of all wind shear slope shear points into Cartesian coordinates; (2) Selecting the Cartesian coordinates of any wind shear slope shear point as the center of a circle, drawing a circular area with the preset minimum distance between two wind shear slope shear points as the radius, and traversing the remaining wind shear slope shear points within the circular area using the Euclidean distance formula; (3) Determine whether each remaining wind shear slope shear point falls within the current circular area. If a remaining wind shear slope shear point falls within the current circular area: When the Euclidean distance between the center of the circle and the wind shear slope shear point falling within the current circular area is less than or equal to a preset minimum distance between two wind shear slope shear points, the wind shear slope shear point falling within the current circular area and the wind shear slope shear point serving as the current center of the circle are clustered into one cluster; (4) updating the position coordinates of the center of the circle to the position coordinates of the wind shear slope shear point falling within the circular area, drawing a new circular area with the preset minimum distance between two wind shear slope shear points as the radius, traversing the remaining wind shear slope shear points within the new circular area using the Euclidean distance formula to obtain a cluster containing wind shear slope shear points, and recording the total number of wind shear slope shear points in the cluster containing wind shear slope shear points, and at the same time estimating the length of the shear line according to the distance formula; (5) Determine whether the total number of shear points on the wind shear slope and the estimated length of the shear line meet the fitting shear line conditions: When the total number of wind shear slope shear points and the estimated length of the shear line do not meet the fitting shear line condition, all wind shear slope shear points in the cluster containing the wind shear slope shear points are removed, and the process returns to step (2) to reselect wind shear slope shear points for cluster analysis; (6) Eliminate the clustered wind shear slope shear point clusters, and repeat steps (2) to (5) based on the currently unclustered wind shear slope shear points until all wind shear slope shear points are clustered, thereby obtaining multiple clusters containing wind shear slope shear points in the target area; According to the multiple clusters containing wind shear slope shear points, clusters that meet the shear line conditions are screened out for curve fitting to obtain all shear lines in the target area, that is, when the total number of wind shear slope shear points and the estimated length of the shear line meet the fitting shear line conditions, all wind shear slope shear points in the cluster containing the wind shear slope shear points are sorted from small to large according to azimuth in a Cartesian coordinate system, and fitting is performed according to a polynomial curve to obtain a shear line, thereby obtaining all shear lines in the target area.

2. The method for wind shear and shear line identification based on laser radar according to claim 1, characterized in that: Before identifying all wind shear slopes in the radial direction from the single radial wind speed data, the method further includes preprocessing the single radial wind speed data using a smoothing formula to eliminate invalid data and isolated data.

3. The method for wind shear and shear line identification based on laser radar according to claim 1, characterized in that: Identifying all wind shear slopes in the radial direction from the single radial wind speed data to obtain a wind shear slope set, including: The detection length of the wind shear slope is changed cyclically, and the speed difference of the wind speed data at the start and end points of each wind shear slope is calculated using a single slope formula at each wind shear slope detection length; Based on the speed difference between the wind speed data at the start and end points of each wind shear slope, and according to a preset wind shear determination standard, all wind shear slopes meeting the conditions in the radial wind speed data are identified; The position coordinates of all wind shear slopes that meet the conditions are recorded to obtain a wind shear slope set.

4. The method for wind shear and shear line identification based on laser radar according to claim 1, characterized in that: According to the wind shear intensity factor, a plurality of wind shear slopes whose wind shear intensity factor values ​​exceed a set threshold are screened from the wind shear slope set, and a plurality of wind shear slopes whose wind shear intensity factor values ​​are larger are extracted to obtain a relatively strong wind shear slope set, including: Using the wind shear intensity factor to evaluate the intensity of each wind shear slope in the wind shear slope set, to obtain intensity factor values ​​of all wind shear slopes; Presetting one or more thresholds for distinguishing between a strong wind shear slope and a weak wind shear slope; Comparing the intensity factor values ​​of all wind shear slopes with the threshold value, and extracting a number of wind shear slopes whose wind shear intensity factor values ​​exceed the set threshold value; Among the several wind shear slopes whose wind shear intensity factor values ​​exceed a set threshold, several wind shear slopes with larger wind shear intensity factor values ​​are extracted to obtain a set of stronger wind shear slopes.

5. The method for wind shear and shear line identification based on laser radar according to claim 1, characterized in that: The calculation method of the total wind shear value of the wind shear slope includes: Based on the wind speed, position and length of the wind shear slope corresponding to the wind shear slope sampling point, the average speed of the wind shear slope is calculated; Based on the wind speed and position corresponding to the wind shear slope sampling point, the total wind energy value of the wind shear slope is calculated; Calculating a wind speed gradient based on the length of the wind shear slope, the average speed of the wind shear slope, and the total wind energy of the wind shear slope, and determining the sign of the wind speed gradient; The total wind shear value of the wind shear slope is calculated based on the wind speed gradient and the length of the wind shear slope.

6. The method for wind shear and shear line identification based on laser radar according to claim 5, characterized in that: When the total wind shear value of the wind shear slope is greater than 0, it indicates that the wind shear slope speed is increasing; when the total wind shear value of the wind shear slope is less than 0, it indicates that the wind shear slope speed is decreasing.

7. The method for wind shear and shear line identification based on laser radar according to claim 1, characterized in that: The method for obtaining the position coordinates of each wind shear slope shear point in the significant wind shear slope set includes: (1) According to the definition of wind shear, at each discontinuity of wind direction or wind speed on the wind shear slope, the position coordinates of the wind direction change point on each wind shear slope are recorded as the position coordinates of the shear point on the wind shear slope, that is, starting from the first sampling point of the wind shear slope, hour, ,in, Indicates The wind speed corresponding to the sampling point is Indicates The wind speed corresponding to the sampling point is represents the total number of wind shear slope sampling points, Indicates The position corresponding to the sampling point, Indicates The position corresponding to the sampling point, represents the distance between the wind shear slope shear point and the wind laser radar, , Indicates Radial wind speed data, , Represents the total number of radial wind speed data. Indicates the first A wind shear slope, , The total number of wind shear slopes representing the strong wind shear level selected in a single radial wind speed data; (2) If the wind direction in the wind shear slope does not change, the position coordinates of the starting point of the wind shear slope are recorded as the position coordinates of the shear point of the wind shear slope. That is, there is no sampling point in the wind shear slope that makes If established, ,in, Indicates the position corresponding to the first sampling point; (3) According to the radar echo data, the radial azimuth information corresponding to the shear point of the wind shear slope is extracted as the ordinate of the shear point , Indicates the azimuth of the wind shear slope shear point.

8. A wind shear and shear line identification system based on laser radar, characterized in that: It includes wind shear identification subsystem and shear line identification subsystem; The wind shear identification subsystem includes the following modules: The radial wind speed acquisition module is used to extract a single radial wind speed data from the radar echo signal of the target area; A wind shear slope identification module, used to identify all wind shear slopes in the radial direction from the single radial wind speed data to obtain a wind shear slope set; A wind shear slope screening module is used to screen a number of wind shear slopes whose wind shear intensity factor values ​​exceed a set threshold from the wind shear slope set according to the wind shear intensity factor, and extract a number of wind shear slopes with larger wind shear intensity factor values ​​to obtain a relatively strong wind shear slope set; A wind shear slope evaluation module, used to respectively calculate the total wind shear value of each wind shear slope in the relatively strong wind shear slope set, evaluate the level of each wind shear slope in the relatively strong wind shear slope set according to a preset wind shear level criterion, and identify the wind shear slope of the strong wind shear level; The shear line identification subsystem includes the following modules: A significant wind shear slope set acquisition module is used to extract all radial wind speed data from the radar echo signal of the target area, repeatedly execute the wind shear identification subsystem, and obtain a significant wind shear slope set in the entire target area; A cluster analysis module is used to perform cluster analysis on all wind shear slope shear points according to the position coordinates of each wind shear slope shear point in the significant wind shear slope set to form a plurality of clusters containing wind shear slope shear points, including: (1) Convert the position coordinates of all wind shear slope shear points into Cartesian coordinates; (2) Selecting the Cartesian coordinates of any wind shear slope shear point as the center of a circle, drawing a circular area with the preset minimum distance between two wind shear slope shear points as the radius, and traversing the remaining wind shear slope shear points within the circular area using the Euclidean distance formula; (3) Determine whether each remaining wind shear slope shear point falls within the current circular area. If a remaining wind shear slope shear point falls within the current circular area: When the Euclidean distance between the center of the circle and the wind shear slope shear point falling within the current circular area is less than or equal to a preset minimum distance between two wind shear slope shear points, the wind shear slope shear point falling within the current circular area and the wind shear slope shear point serving as the current center of the circle are clustered into one cluster; (4) updating the position coordinates of the center of the circle to the position coordinates of the wind shear slope shear point falling within the circular area, drawing a new circular area with the preset minimum distance between two wind shear slope shear points as the radius, traversing the remaining wind shear slope shear points within the new circular area using the Euclidean distance formula to obtain a cluster containing wind shear slope shear points, and recording the total number of wind shear slope shear points in the cluster containing wind shear slope shear points, and at the same time estimating the length of the shear line according to the distance formula; (5) Determine whether the total number of shear points on the wind shear slope and the estimated length of the shear line meet the fitting shear line conditions: When the total number of wind shear slope shear points and the estimated length of the shear line do not meet the fitting shear line condition, all wind shear slope shear points in the cluster containing the wind shear slope shear points are removed, and the process returns to step (2) to reselect wind shear slope shear points for cluster analysis; (6) Eliminate the clustered wind shear slope shear point clusters, and repeat steps (2) to (5) based on the currently unclustered wind shear slope shear points until all wind shear slope shear points are clustered, thereby obtaining multiple clusters containing wind shear slope shear points in the target area; The shear line identification module is used to screen out clusters that meet the shear line conditions based on the multiple clusters containing wind shear slope shear points, and perform curve fitting to obtain all shear lines in the target area. That is, when the total number of wind shear slope shear points and the estimated length of the shear line meet the shear line fitting condition, all wind shear slope shear points in the cluster containing the wind shear slope shear points are sorted from small to large according to azimuth in a Cartesian coordinate system, and fit according to a polynomial curve to obtain a shear line, thereby obtaining all shear lines in the target area.

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