A method and apparatus for monitoring the deviation of a phased array weather radar scan beam

Abstract

The present disclosure relates to the technical field of meteorological detection, and particularly relates to a method and device for monitoring deviation of scanning beam of phased array weather radar. The method comprises: receiving radar scanning data and identifying whether it is valid precipitation echo; if yes, adjusting the azimuth angle of the radar to a first position according to the radar scanning data; at the first position, adjusting the elevation angle of the antenna to at least two preset angles, and adjusting the deflection angle of the antenna at each preset angle, so that the area scanned by the deflection angle of the antenna at one preset angle and the area scanned by the normal direction of the antenna at another preset angle overlap; receiving observation data after adjusting the elevation angle of the antenna and the deflection angle of the antenna; and determining whether to calibrate the radar according to the observation data and a preset threshold. The above technical solution solves the problem that there is no effective method to determine when to calibrate the phased array weather radar in the prior art.

Description

Technical Field

[0001] This disclosure relates to the field of meteorological detection technology, specifically to a method and apparatus for monitoring the deviation of a phased array weather radar scanning beam. Background Technology

[0002] Weather radar has wide applications in severe weather monitoring, quantitative precipitation estimation, and numerical model assimilation. Currently, weather radar mainly uses a mechanical scanning system. Although this system can meet routine operational needs, its temporal resolution and adaptive scanning capabilities still require improvement. Phased array weather radar is a novel meteorological observation device that can achieve electronic scanning by controlling the phase, offering significant improvements in scanning speed and flexibility compared to mechanically scanned radar.

[0003] Despite the advantages mentioned above, phased array weather radars, when the radar beam deviates from the normal (i.e., when observation is performed using a scanning beam), will result in deviations in the radar parameters detected by the phased array weather radar relative to the normal due to factors such as changes in the antenna pattern and mismatch between the horizontal and vertical polarization channels. Therefore, before leaving the factory, the performance of the phased array antenna of a phased array weather radar is measured using a microwave anechoic chamber or other methods to correct for deviations in the scanning beam.

[0004] During long-term operation of phased array weather radars, the original calibration parameters become inapplicable due to factors such as component aging. This necessitates recalibrating the scanning beam deviation of the phased array weather radar. However, the calibration process for phased array weather radars is time-consuming. Since there is no effective method in current technology to determine when to calibrate phased array weather radars, a problem arises: too high a calibration frequency is detrimental to radar observation operations, while too low a calibration frequency cannot guarantee the quality of radar observation data. Summary of the Invention

[0005] To address the problems in the related technologies, this disclosure provides a method and apparatus for monitoring the deviation of the scanning beam of a phased array weather radar.

[0006] In a first aspect, this disclosure provides a method for monitoring the deviation of a phased array weather radar scanning beam.

[0007] Specifically, the method for monitoring the deviation of the phased array weather radar scanning beam includes:

[0008] Receive radar scan data and identify whether it is a valid precipitation echo;

[0009] If so, the radar azimuth angle is adjusted to the first position according to the radar scanning data;

[0010] At the first position, the elevation angle of the antenna is adjusted to at least two preset angles, and the deflection angle of the antenna is adjusted at each preset angle so that the deflection angle of the antenna at one preset angle is adjusted to overlap with the area scanned by the antenna in the normal direction at another preset angle.

[0011] Receive observation data after adjusting the elevation angle and deflection angle of the antenna;

[0012] Whether to calibrate the radar is determined based on the observation data and a preset threshold.

[0013] Optionally, receiving radar scan data and identifying whether it is a valid precipitation echo includes:

[0014] It receives radar scan data and identifies echo types after eliminating non-meteorological echoes;

[0015] If there is no echo, it is identified as a non-valid precipitation echo;

[0016] If the echo type is convective precipitation echo or stratiform precipitation echo, it is identified as a valid precipitation echo.

[0017] Optionally, the echo type identification step includes:

[0018] Set the threshold range for vertical cumulative liquid water content and the threshold range for distance from the reservoir;

[0019] The number of first distance reservoirs whose vertical cumulative liquid water content is lower than the lower limit of the vertical cumulative liquid water content threshold range is counted. If the number of first distance reservoirs is lower than the lower limit of the distance reservoir number threshold range, it is identified as an ineffective precipitation echo.

[0020] The number of second-distance reservoirs whose vertical cumulative liquid water content is higher than the upper limit of the threshold range of vertical cumulative liquid water content is counted. If the number of second-distance reservoirs is higher than the upper limit of the threshold range of the number of distance reservoirs, it is identified as a convective precipitation echo.

[0021] If the first distance reservoir number is not lower than the lower limit of the distance reservoir number threshold range and the second distance reservoir number is not higher than the upper limit of the distance reservoir number threshold range, then it is identified as a layered precipitation echo.

[0022] Optionally, the radar scanning data is obtained by traversing all azimuth angles;

[0023] The step of adjusting the radar azimuth to the first position based on the radar scanning data includes:

[0024] The number of third-range reservoirs containing valid precipitation echoes in the radar scan data is counted.

[0025] The azimuth angle with the largest third distance value is selected as the first position;

[0026] Adjust the azimuth angle of the radar to the first position.

[0027] Optionally, the antenna may have multiple deflection angles, and the deflection angles of the multiple antennas may be adjusted in preset steps with the antenna's normal direction as the center.

[0028] Optionally, determining whether to calibrate the radar based on the observation data and a preset threshold includes:

[0029] The observation data of the area scanned in the normal direction of the antenna is taken as the true value;

[0030] After adjusting the elevation angle and deflection angle of the antenna, calculate the difference between at least two observation data points that overlap with the area scanned in the normal direction of the antenna and the true value;

[0031] Determine whether the average value of the difference is greater than the preset threshold. If so, calibrate the radar.

[0032] Optionally, the calibration of the radar includes:

[0033] The radar was calibrated using the metal ball method.

[0034] Secondly, this disclosure provides a phased array weather radar scanning beam deviation monitoring device.

[0035] Specifically, the phased array weather radar scanning beam deviation monitoring device includes:

[0036] The identification module is configured to receive radar scan data and identify whether it is a valid precipitation echo.

[0037] If the judgment module is configured to, then the azimuth angle of the radar is adjusted to the first position based on the radar scanning data.

[0038] The adjustment module is configured to adjust the elevation angle of the antenna to at least two preset angles at the first position, and adjust the deflection angle of the antenna at each preset angle, so that the deflection angle of the antenna at one preset angle is adjusted to overlap with the area scanned by the antenna in the normal direction at another preset angle.

[0039] The receiving module is configured to receive observation data after adjusting the elevation angle and deflection angle of the antenna;

[0040] The determination module is configured to determine whether to calibrate the radar based on the observation data and a preset threshold.

[0041] Optionally, the identification module includes:

[0042] It receives radar scan data and identifies echo types after eliminating non-meteorological echoes;

[0043] If there is no echo, it is identified as a non-valid precipitation echo;

[0044] If the echo type is convective precipitation echo or stratiform precipitation echo, it is identified as a valid precipitation echo.

[0045] Optionally, the echo type identification step includes:

[0046] Set the threshold range for vertical cumulative liquid water content and the threshold range for distance from the reservoir;

[0047] The number of first distance reservoirs whose vertical cumulative liquid water content is lower than the lower limit of the vertical cumulative liquid water content threshold range is counted. If the number of first distance reservoirs is lower than the lower limit of the distance reservoir number threshold range, it is identified as an ineffective precipitation echo.

[0048] The number of second-distance reservoirs whose vertical cumulative liquid water content is higher than the upper limit of the threshold range of vertical cumulative liquid water content is counted. If the number of second-distance reservoirs is higher than the upper limit of the threshold range of the number of distance reservoirs, it is identified as a convective precipitation echo.

[0049] If the first distance reservoir number is not lower than the lower limit of the distance reservoir number threshold range and the second distance reservoir number is not higher than the upper limit of the distance reservoir number threshold range, then it is identified as a layered precipitation echo.

[0050] Optionally, the radar scanning data is obtained by traversing all azimuth angles;

[0051] The judgment module includes:

[0052] The number of third-range reservoirs containing valid precipitation echoes in the radar scan data is counted.

[0053] The azimuth angle with the largest third distance value is selected as the first position;

[0054] Adjust the azimuth angle of the radar to the first position.

[0055] Optionally, the antenna may have multiple deflection angles, and the deflection angles of the multiple antennas may be adjusted in preset steps with the antenna's normal direction as the center.

[0056] Optionally, the determining module includes:

[0057] The observation data of the area scanned in the normal direction of the antenna is taken as the true value;

[0058] After adjusting the elevation angle and deflection angle of the antenna, calculate the difference between at least two observation data points that overlap with the area scanned in the normal direction of the antenna and the true value;

[0059] Determine whether the average value of the difference is greater than the preset threshold. If so, calibrate the radar.

[0060] Optionally, the calibration of the radar includes:

[0061] The radar was calibrated using the metal ball method.

[0062] Thirdly, embodiments of this disclosure provide an electronic device including a memory and a processor, wherein the memory is used to store one or more computer instructions, wherein the one or more computer instructions are executed by the processor to implement the method as described in any of the first aspects.

[0063] Fourthly, this disclosure provides a computer-readable storage medium having computer instructions stored thereon, which, when executed by a processor, implement the method as described in any of the first aspects.

[0064] According to the phased array weather radar scanning beam deviation monitoring method and apparatus provided in this disclosure, the method includes: receiving radar scanning data and identifying whether it is a valid precipitation echo; if so, adjusting the radar azimuth angle to a first position based on the radar scanning data; at the first position, adjusting the antenna elevation angle to at least two preset angles, and adjusting the antenna deflection angle at each preset angle, such that the area scanned by the antenna at one preset angle overlaps with the area scanned by the antenna in the normal direction at another preset angle; receiving observation data after adjusting the antenna elevation angle and antenna deflection angle; and determining whether to calibrate the radar based on the observation data and a preset threshold. The above technical solution involves receiving and analyzing radar scanning data to identify the presence of valid precipitation echoes. If valid precipitation echoes are present, the radar azimuth angle is adjusted to a first position based on the scanning data. This first position is the optimal azimuth angle calculated from the radar scanning data, ensuring that the scanning beam covers more precipitation echoes. At this first position, the antenna elevation angle is adjusted to at least two preset angles, and the antenna deflection angle is further adjusted at each preset angle. This ensures that the antenna deflection angle at one preset angle corresponds to the scanning area at a certain position, while simultaneously overlapping with the scanning area in the antenna's normal direction at another preset angle. The radar receives the observation data detected by the adjusted antenna elevation and deflection angles. By analyzing the observation data and comparing it with preset thresholds, it determines whether radar calibration is necessary. If the observation data meets expectations and the deviation is within the preset threshold range, radar calibration is unnecessary. Conversely, if the deviation exceeds the preset threshold, radar calibration is required to ensure the accuracy and stability of the scanning beam, thereby guaranteeing the accuracy and reliability of the observation data. This solves the problem in existing technologies where the timing of calibration for phased array weather radar is uncertain, leading to situations where excessively high calibration frequencies hinder radar observation operations, or excessively low calibration frequencies fail to guarantee the quality of radar observation data.

[0065] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0066] Other features, objects, and advantages of this disclosure will become more apparent from the following detailed description of non-limiting embodiments, taken in conjunction with the accompanying drawings. In the drawings:

[0067] Figure 1 A flowchart illustrating a method for monitoring the deviation of a phased array weather radar scanning beam according to an embodiment of the present disclosure is shown.

[0068] Figure 2 A step diagram illustrating a method for monitoring the deviation of a phased array weather radar scanning beam according to an embodiment of the present disclosure is shown.

[0069] Figure 3 A schematic diagram showing the position of the mechanical elevation and deflection angles of a phased array weather radar according to an embodiment of the present disclosure.

[0070] Figures 4a-4f The figure shows simulation results of a phased array weather radar scanning beam deviation monitoring method according to an embodiment of the present disclosure.

[0071] Figure 5 A structural block diagram of a phased array weather radar scanning beam deviation monitoring device according to an embodiment of the present disclosure is shown.

[0072] Figure 6 A structural block diagram of an electronic device according to an embodiment of the present disclosure is shown.

[0073] Figure 7 A schematic diagram of the structure of a computer system suitable for implementing the method according to embodiments of the present disclosure is shown. Detailed Implementation

[0074] In the following, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings to enable those skilled in the art to readily implement them. Furthermore, for clarity, portions unrelated to the description of exemplary embodiments have been omitted from the drawings.

[0075] In this disclosure, it should be understood that terms such as “comprising” or “having” are intended to indicate the presence of features, figures, steps, behaviors, components, parts or combinations thereof disclosed in this specification, and are not intended to exclude the possibility of the presence or addition of one or more other features, figures, steps, behaviors, components, parts or combinations thereof.

[0076] It should also be noted that, unless otherwise specified, the embodiments and features described in this disclosure can be combined with each other. This disclosure will now be described in detail with reference to the accompanying drawings and embodiments.

[0077] In this disclosure, any operation involving the acquisition of user information or user data, or the display of user information or user data to others, is an operation authorized or confirmed by the user, or actively selected by the user.

[0078] Weather radar has wide applications in severe weather monitoring, quantitative precipitation estimation, and numerical model assimilation. Currently, weather radar mainly uses a mechanical scanning system. Although this system can meet routine operational needs, its temporal resolution and adaptive scanning capabilities still require improvement. Phased array weather radar is a novel meteorological observation device that can achieve electronic scanning by controlling the phase, offering significant improvements in scanning speed and flexibility compared to mechanically scanned radar.

[0079] Despite the advantages mentioned above, phased array weather radars, when the radar beam deviates from the normal (i.e., when observation is performed using a scanning beam), will result in deviations in the radar parameters detected by the phased array weather radar relative to the normal due to factors such as changes in the antenna pattern and mismatch between the horizontal and vertical polarization channels. Therefore, before leaving the factory, the performance of the phased array antenna of a phased array weather radar is measured using a microwave anechoic chamber or other methods to correct for deviations in the scanning beam.

[0080] During long-term operation of phased array weather radars, the original calibration parameters become inapplicable due to factors such as component aging. This necessitates recalibrating the scanning beam deviation of the phased array weather radar. However, the calibration process for phased array weather radars is time-consuming. Since there is no effective method in current technology to determine when to calibrate phased array weather radars, a problem arises: too high a calibration frequency is detrimental to radar observation operations, while too low a calibration frequency cannot guarantee the quality of radar observation data.

[0081] Figure 1 A flowchart illustrating a method for monitoring the deviation of a phased array weather radar scanning beam according to an embodiment of the present disclosure is shown.

[0082] like Figure 1 As shown, the method for monitoring the deviation of the phased array weather radar scanning beam includes the following steps S101-S105:

[0083] Step S101: Receive radar scan data and identify whether it is a valid precipitation echo;

[0084] Step S102: If so, adjust the radar azimuth to the first position according to the radar scanning data;

[0085] Step S103: At the first position, adjust the elevation angle of the antenna to at least two preset angles, and adjust the deflection angle of the antenna at each preset angle so that the deflection angle of the antenna at one preset angle is adjusted to overlap with the area scanned by the antenna in the normal direction at another preset angle.

[0086] Step S104: Receive the observation data after adjusting the elevation angle and deflection angle of the antenna;

[0087] Step S105: Determine whether to calibrate the radar based on the observation data and the preset threshold.

[0088] The phased array weather radar scanning beam deviation monitoring method provided in this disclosure involves receiving and analyzing scanning data from the radar to identify the presence of valid precipitation echoes. If valid precipitation echoes are present, the radar azimuth angle is adjusted to a first position based on the scanning data. This first position is the optimal azimuth angle calculated from the radar scanning data, ensuring that the scanning beam covers more precipitation echoes. At the first position, the antenna elevation angle is adjusted to at least two preset angles, and the antenna deflection angle is further adjusted at each preset angle so that the antenna deflection angle at one preset angle corresponds to the scanning area at a certain position, while simultaneously overlapping with the scanning area in the normal direction of the antenna at another preset angle. The radar receives the observation data detected by the adjusted antenna elevation and deflection angles. By analyzing the observation data and comparing it with preset thresholds, it determines whether radar calibration is required. If the observation data meets expectations and the deviation is within the preset threshold range, radar calibration is unnecessary; otherwise, if the deviation exceeds the preset threshold, radar calibration is required to ensure the accuracy and stability of the scanning beam, thereby guaranteeing the accuracy and reliability of the observation data. This solves the problem in existing technologies where the timing of calibration for phased array weather radar is uncertain, leading to situations where excessively high calibration frequencies hinder radar observation operations, or excessively low calibration frequencies fail to guarantee the quality of radar observation data.

[0089] According to embodiments of this disclosure, in step S101, namely, receiving radar scan data and identifying whether it is a valid precipitation echo, the step of receiving radar scan data and identifying whether it is a valid precipitation echo includes:

[0090] It receives radar scan data and identifies echo types after eliminating non-meteorological echoes;

[0091] If there is no echo, it is identified as a non-valid precipitation echo;

[0092] If the echo type is convective precipitation echo or stratiform precipitation echo, it is identified as a valid precipitation echo.

[0093] According to embodiments of this disclosure, the scan data received by a phased array weather radar may contain various types of echo signals, including meteorological echoes and non-meteorological echoes (such as ground object echoes, electromagnetic interference echoes, etc.). First, the received scan data is processed to remove the influence of non-meteorological echoes, for example, by using ground object echo filtering algorithms, electromagnetic interference echo filtering algorithms, etc., to eliminate non-meteorological echo signals.

[0094] After eliminating the influence of non-meteorological echoes, two situations will arise: one is no meteorological echo, i.e., no echo; the other is that there are meteorological echoes, which allows for specific analysis of the echo type.

[0095] If no echo is detected, it is identified as a non-effective precipitation echo. That is, after eliminating non-meteorological echoes, if no echo signal is detected in the scanned target area, it can be determined as a non-effective precipitation echo. This situation may occur under weather conditions with no precipitation or weak precipitation, or due to radar malfunctions or other reasons that prevent the reception of effective echo signals. If it is due to weather conditions, the monitoring can be stopped; if it is due to radar malfunction, staff must promptly repair and resolve the fault and restart monitoring.

[0096] If the echo type is convective precipitation echo or stratiform precipitation echo, it is identified as a valid precipitation echo. Based on the characteristics and morphology of the echoes, the remaining echo signals after removing non-meteorological echoes are identified by type. Convective precipitation echoes are characterized by strong intensity, irregular shape, and rapid spatial variation; while stratiform precipitation echoes have a uniform and continuous echo distribution. If the echo type is identified as convective precipitation echo or stratiform precipitation echo, it can be determined as a valid precipitation echo.

[0097] By identifying the echo type of the received radar scan data, effective precipitation echoes can be distinguished from ineffective precipitation echoes. This helps to focus on processing and analyzing only effective precipitation echo signals during subsequent radar scan beam adjustments and monitoring, thereby improving monitoring efficiency.

[0098] Specifically, the echo type identification steps include:

[0099] Set the threshold range for vertical cumulative liquid water content and the threshold range for distance from the reservoir;

[0100] The number of first distance reservoirs whose vertical cumulative liquid water content is lower than the lower limit of the vertical cumulative liquid water content threshold range is counted. If the number of first distance reservoirs is lower than the lower limit of the distance reservoir number threshold range, it is identified as an ineffective precipitation echo.

[0101] The number of second-distance reservoirs whose vertical cumulative liquid water content is higher than the upper limit of the threshold range of vertical cumulative liquid water content is counted. If the number of second-distance reservoirs is higher than the upper limit of the threshold range of the number of distance reservoirs, it is identified as a convective precipitation echo.

[0102] If the first distance reservoir number is not lower than the lower limit of the distance reservoir number threshold range and the second distance reservoir number is not higher than the upper limit of the distance reservoir number threshold range, then it is identified as a layered precipitation echo.

[0103] The vertical cumulative liquid water content (VIL) threshold range and the distance reservoir number threshold range can be determined based on historical data, meteorological statistics, and staff experience. The echo type identification steps include: first, counting the number of first distance reservoirs below the set lower limit of the VIL threshold; if the first distance reservoir number is lower than the lower limit of the distance reservoir number threshold range, it is identified as a non-effective precipitation echo; then, radar scan data of effective precipitation echoes are used for deviation monitoring. In the embodiments of this disclosure, effective precipitation echoes can be convective precipitation echoes or stratiform precipitation echoes. Preferably, the deviation monitoring method of this disclosure is more accurate and reliable when applied to observation data of stratiform precipitation echoes.

[0104] According to an embodiment of this disclosure, in step S102, if so, the radar scanning data is obtained by traversing all azimuth angles in the step of adjusting the azimuth angle of the radar to the first position based on the radar scanning data.

[0105] The step of adjusting the radar azimuth to the first position based on the radar scanning data includes:

[0106] The number of third-range reservoirs containing valid precipitation echoes in the radar scan data is counted.

[0107] The azimuth angle with the largest third distance value is selected as the first position;

[0108] Adjust the azimuth angle of the radar to the first position.

[0109] Specifically, the radar scan data obtained after traversing all azimuth angles is first analyzed to count the number of third-range echoes with effective precipitation at different azimuth angles. Then, based on the statistical results, the azimuth angle with the highest third-range echo count is selected as the first position, or optimal azimuth angle. The highest third-range echo count corresponds to the area with the strongest precipitation or the widest distribution range; therefore, adjusting the radar azimuth angle to this position maximizes coverage of the effective precipitation area. Finally, the azimuth angle of the phased array weather radar is adjusted to this first position. This ensures that the radar scanning beam's scanning range is focused on this first position, improving the radar's comprehensive observation and monitoring capabilities of the precipitation area.

[0110] According to embodiments of this disclosure, step S103 involves adjusting the antenna elevation angle to at least two preset angles at the first position, and adjusting the antenna deflection angle at each preset angle. This ensures that the area scanned at one preset angle overlaps with the area scanned by the antenna in the normal direction at another preset angle. By continuously adjusting the radar antenna elevation and deflection angles, a wider scanning area is covered, and overlapping scans between scanning areas at different elevation and deflection angles are ensured. By monitoring the deviation of the observation data in the overlapping scanning areas, it is determined whether radar calibration is required. Furthermore, by receiving and processing radar scanning data in real-time or periodically, the monitoring process becomes more efficient, allowing staff to promptly determine whether radar calibration is necessary, thereby ensuring the continuity and stability of radar detection data.

[0111] Furthermore, in the embodiments of this disclosure, the antenna has multiple deflection angles, which are adjusted in preset steps around the antenna's normal direction. These multiple deflection angles can be preset according to weather conditions, observation requirements, or experimental design. For example, a deflection angle threshold range can be set to ensure coverage of the target area and acquisition of the required observation data. When setting the deflection angles, the antenna's normal direction (the direction perpendicular to the antenna's main axis) can be used as the center. Multiple deflection angles are sequentially set on both sides of the antenna's normal direction in preset steps, enabling the antenna to scan and observe in different directions. When setting multiple deflection angles, they can be adjusted in preset steps. A step refers to the interval between deflection angles, which can be a fixed angle value or set according to actual needs. By adjusting the deflection angles in preset steps, it can be ensured that the radar scanning beam fully covers and observes the entire scanning range, enabling scanning and observation in different directions, obtaining observation data at multiple angles, and further improving the monitoring accuracy and reliability of the weather radar.

[0112] According to embodiments of this disclosure, in step S104, which is the step of receiving observation data after adjusting the elevation angle and deflection angle of the antenna, the observation data may be, for example, the reflectivity factor Z. H Differential reflectivity Z DR Differential propagation phase shift Φ DP Correlation coefficient ρ HV Etc. It is understood that the radar observation data disclosed herein is not limited to this, and those skilled in the art may add or reduce it as needed.

[0113] According to embodiments of this disclosure, step S105, which is the step of determining whether to calibrate the radar based on the observation data and a preset threshold, includes:

[0114] The observation data of the area scanned in the normal direction of the antenna is taken as the true value;

[0115] After adjusting the elevation angle and deflection angle of the antenna, calculate the difference between at least two observation data points that overlap with the area scanned in the normal direction of the antenna and the true value;

[0116] Determine whether the average value of the difference is greater than the preset threshold. If so, calibrate the radar.

[0117] In this embodiment, the observation data obtained within the normal direction scanning area of ​​the antenna is first used as a true reference. Then, by adjusting the antenna's elevation and deflection angles, the antenna's observation range is adjusted to the target area to obtain at least two observation datasets overlapping the normal direction scanning area. Afterward, for the observation datasets overlapping the normal direction scanning area, the differences between them and the true values ​​are calculated, for example, by comparing the reflectivity factor Z. H Differential reflectivity Z DR Differential propagation phase shift Φ DP Correlation coefficient ρ HV The system calculates the average of the differences and compares it to a preset threshold. If the average difference is greater than the preset threshold, it indicates a significant deviation between the observed data and the true value, requiring radar calibration. This allows for timely detection and correction of radar deviations, ensuring the reliability and accuracy of radar observation data. If the average difference is less than the preset threshold, radar calibration is unnecessary.

[0118] In the embodiments of this disclosure, the metal sphere method can be used for radar calibration. The metal sphere method calibrates the radar by placing a metal sphere with known radar scattering characteristics within the radar's observation range. The reflection characteristics of the metal sphere can be measured and calibrated in advance, and it has good echo characteristics. By placing the metal sphere within the radar's observation range, the difference between the observed spherical reflection signal and the known characteristics of the metal sphere can be compared, thereby evaluating the calibration status of the radar system. This calibration method is highly reliable, simple to operate, and has good repeatability. It is understood that other calibration methods can also be used to calibrate phased array weather radars, and this disclosure does not limit this method.

[0119] Figure 2 A step diagram illustrating a method for monitoring the deviation of a phased array weather radar scanning beam according to an embodiment of the present disclosure is shown. Figure 3 A schematic diagram showing the position of the mechanical elevation and deflection angles of a phased array weather radar according to an embodiment of the present disclosure.

[0120] like Figure 2 As shown, the specific steps of the phased array weather radar scanning beam deviation monitoring method disclosed herein include:

[0121] (1) Data input and parameter configuration: The monitoring method of this disclosure is executed periodically to determine whether the deviation monitoring cycle is met. If it is met, the latest volume scan observation data of the radar (i.e., Z) is input during execution. H Z DR Φ DP ρ HV ); ρ used for quality control HV Thresholds; VIL (Vertical Cumulative Liquid Water Content) lower threshold, VIL upper threshold, range reservoir number threshold 1, and range reservoir number threshold 2 for echo type identification; setting the radar mechanical elevation angle rotation range, mechanical elevation angle rotation step, radar scanning beam deflection angle range (relative to the normal), and scanning beam step (same as mechanical elevation angle rotation step); and deviation thresholds for each radar parameter.

[0122] (2) Radar Data Quality Control: The monitoring method disclosed herein is illustrated using deviation monitoring based on stratiform precipitation echoes as an example. When performing deviation monitoring on stratiform precipitation echoes, it is necessary to perform quality control on the radar data to eliminate the influence caused by non-meteorological echoes (such as ground clutter, sea clutter, biological echoes, electromagnetic interference echoes, etc.). The monitoring method disclosed herein uses a ρ... HV The threshold will be lower than ρ HV The distance to the threshold is identified as being affected by non-meteorological echo interference and is removed.

[0123] (3) Echo Type Identification: The monitoring method of this disclosure takes deviation monitoring based on stratiform precipitation echoes as an example. When performing deviation monitoring on stratiform precipitation echoes, it is necessary to identify the echo type. If the identification result is no effective precipitation echo or convective precipitation echo, the subsequent process will not be carried out. On the one hand, this avoids the situation of no effective precipitation echo under clear sky conditions, and on the other hand, it avoids the distortion of monitoring results caused by the rapid evolution of convective precipitation echoes. The monitoring method of this disclosure calculates the VIL of the volume scan observation data and performs two-dimensional median filtering on it to suppress the influence of residual non-meteorological echoes; counts the number of distance reservoirs where the VIL exceeds the lower threshold. If the number is lower than the distance reservoir number threshold 1, it is identified as no effective precipitation echo; counts the number of distance reservoirs where the VIL exceeds the upper threshold. If the number is higher than the distance reservoir number threshold 2, it is identified as convective precipitation echo; other cases are considered as stratiform precipitation.

[0124] (4) Adjusting the radar azimuth: Since the accuracy and stability of the monitoring method disclosed herein will improve with the increase of data volume, deviation monitoring needs to be performed at the azimuth angle with the most effective precipitation echo ranges. The monitoring method disclosed herein traverses all azimuth angles and counts the number of ranges with precipitation echoes, and adjusts the radar to the azimuth angle position with the most ranges.

[0125] (5) Adjust the radar's mechanical elevation angle and perform an electronic scan: such as Figure 3 As shown, with Figure 3 The following steps are explained using the corresponding parameters as an example. The radar's mechanical elevation angle is gradually adjusted in increments of Δθ within the range of θ1 to θ3 (where Δθ = θ3 – θ2 = θ2 – θ1), so that the antenna normal covers different areas as the elevation angle changes. After each adjustment of the radar's mechanical elevation angle, electronic scanning is performed in increments of Δθ within the range of -2Δθ to 2Δθ, according to a predetermined deflection angle configuration.

[0126] (6) Deviation estimation: Please refer to the following: Figure 3 After completing all preset mechanical elevation angle adjustments and electronic scanning, all observation data were statistically analyzed.

[0127] At an elevation angle of θ1, the radar performs three observations: Observation 1 (radar mechanical elevation angle θ1, scanning beam deflection angle 0), Observation 2 (radar mechanical elevation angle θ2, scanning beam deflection angle -Δθ), and Observation 3 (radar mechanical elevation angle θ3, scanning beam deflection angle -2Δθ). Since Observation 1 is an observation performed in the normal direction, there is no scanning beam deviation. Therefore, the radar parameters obtained from Observation 1 are taken as the true values. The differences between these true values ​​and the radar parameters obtained from Observation 2 and Observation 3 are calculated, and the results are used as the deviations of the corresponding deflection angles (Observation 2 corresponds to -Δθ, and Observation 3 corresponds to -2Δθ).

[0128] At a deflection angle of -Δθ, the radar can perform multiple deviation estimates. For example, a single estimate can be made when the radar's mechanical elevation angle is θ1 and the scanning beam deflection angle is 0, and the same can be made when the radar's mechanical elevation angle is θ2 and the scanning beam deflection angle is -Δθ. By averaging the deviations from these multiple estimates, a more accurate result can be obtained.

[0129] After estimating the deviation of each radar parameter corresponding to each scanning beam, it is compared with a preset threshold. If the obtained deviation is greater than the preset threshold, it indicates that the radar calibration deviation has changed significantly and high-precision calibration (such as the metal ball method) is required to ensure the accuracy of radar detection data. At this time, the staff on duty are prompted that the radar needs to be calibrated.

[0130] Figures 4a-4f The figure shows simulation results of a phased array weather radar scanning beam deviation monitoring method according to an embodiment of the present disclosure.

[0131] like Figures 4a-4f As shown, simulation data is used to verify the effectiveness of the monitoring method disclosed herein, as follows:

[0132] (1) Extract RHI data (including Z) of a typical stratified precipitation process. H Z DR Φ DP (abbreviated as "raw data").

[0133] (2) To simulate the change of the stratified precipitation process over time, Gaussian random noise with a standard deviation of δ (δ has different values ​​for different radar parameters) is superimposed on the original data to form a new set of RHI data (referred to as "simulation data 1"). The above operation on the original data is repeated for simulation data 1 to generate simulation data 2, and so on to generate a series of simulation data, namely simulation data 1, simulation data 2... simulation data N.

[0134] (3) Existing research results indicate that Z obtained from phased array weather radar scanning beam observations H Z DR Φ DP The relationship between the deviation and the deflection angle is approximately a sine function. Therefore, Z is generated based on this characteristic. H Z DR Φ DP Theoretical deviations.

[0135] (4) Assuming that the simulation data 1 to N are the results obtained from observations by the phased array weather radar at different mechanical elevation angles (from which the normal of the phased array weather radar can be determined), the generated Z H Z DR Φ DP The theoretical deviations are superimposed onto the simulation data 1 to N (ensuring the deviation is 0 at the normal direction), thereby simulating the observation results of the phased array weather radar at different mechanical elevation angles.

[0136] (5) The monitoring method of this disclosure is used to estimate the deviation corresponding to the simulation data, and the results are shown in the figure. Wherein, Figure 4a It is δ(Z) H The simulation results are shown in the figure with a value of 1dB. Figure 4b It is δ(Z) DR The simulation results are shown in the figure with a value of 0.3dB. Figure 4c It is δ(Φ) DP The simulation results are shown for angle 10°. Figure 4d It is δ(Z) H The simulation results are shown in the figure with a value of 3dB. Figure 4e It is δ(Z) DR The simulation results are shown in the figure with a value of 1dB. Figure 4f It is δ(Φ) DPThe simulation results are shown in the figure for δ = 30°. The simulation results show that when δ is small (corresponding to slowly changing stratified precipitation), the monitoring method of this disclosure has high monitoring accuracy; however, as δ increases (corresponding to faster-changing convective precipitation), the monitoring accuracy of the method of this disclosure decreases.

[0137] Figure 5 A structural block diagram of a phased array weather radar scanning beam deviation monitoring device according to an embodiment of the present disclosure is shown. This device can be implemented as part or all of an electronic device through software, hardware, or a combination of both.

[0138] like Figure 5 As shown, the phased array weather radar scanning beam deviation monitoring device 500 includes:

[0139] The identification module 510 is configured to receive radar scan data and identify whether it is a valid precipitation echo.

[0140] If the judgment module 520 is configured to adjust the radar azimuth to the first position according to the radar scanning data, then if the condition is met.

[0141] The adjustment module 530 is configured to adjust the elevation angle of the antenna to at least two preset angles at the first position, and adjust the deflection angle of the antenna at each preset angle, so that the deflection angle of the antenna at one preset angle is adjusted to overlap with the area scanned by the antenna in the normal direction at another preset angle.

[0142] The receiving module 540 is configured to receive observation data after adjusting the elevation angle and deflection angle of the antenna;

[0143] The determination module 550 is configured to determine whether to calibrate the radar based on the observation data and a preset threshold.

[0144] The phased array weather radar scanning beam deviation monitoring device provided in this embodiment receives and analyzes scanning data from the radar to identify the presence of valid precipitation echoes. If valid precipitation echoes are present, the radar azimuth angle is adjusted to a first position based on the scanning data. This first position is the optimal azimuth angle calculated from the radar scanning data, ensuring that the scanning beam covers more precipitation echoes. The antenna elevation angle is adjusted to at least two preset angles at the first position, and the antenna deflection angle is further adjusted at each preset angle so that the antenna deflection angle at one preset angle corresponds to the scanning area at a certain position, while simultaneously overlapping with the scanning area in the normal direction of the antenna at another preset angle. The radar receives the observation data detected by the adjusted antenna elevation and deflection angles. By analyzing the observation data and comparing it with preset thresholds, it determines whether radar calibration is required. If the observation data meets expectations and the deviation is within the preset threshold range, radar calibration is unnecessary; otherwise, if the deviation exceeds the preset threshold, radar calibration is required to ensure the accuracy and stability of the scanning beam, thereby guaranteeing the accuracy and reliability of the observation data. This solves the problem in existing technologies where the timing of calibration for phased array weather radar is uncertain, leading to situations where excessively high calibration frequencies hinder radar observation operations, or excessively low calibration frequencies fail to guarantee the quality of radar observation data.

[0145] According to an embodiment of this disclosure, the identification module 510 includes:

[0146] It receives radar scan data and identifies echo types after eliminating non-meteorological echoes;

[0147] If there is no echo, it is identified as a non-valid precipitation echo;

[0148] If the echo type is convective precipitation echo or stratiform precipitation echo, it is identified as a valid precipitation echo.

[0149] According to embodiments of this disclosure, the echo type identification step includes:

[0150] Set the threshold range for vertical cumulative liquid water content and the threshold range for distance from the reservoir;

[0151] The number of first distance reservoirs whose vertical cumulative liquid water content is lower than the lower limit of the vertical cumulative liquid water content threshold range is counted. If the number of first distance reservoirs is lower than the lower limit of the distance reservoir number threshold range, it is identified as an ineffective precipitation echo.

[0152] The number of second-distance reservoirs whose vertical cumulative liquid water content is higher than the upper limit of the threshold range of vertical cumulative liquid water content is counted. If the number of second-distance reservoirs is higher than the upper limit of the threshold range of the number of distance reservoirs, it is identified as a convective precipitation echo.

[0153] If the first distance reservoir number is not lower than the lower limit of the distance reservoir number threshold range and the second distance reservoir number is not higher than the upper limit of the distance reservoir number threshold range, then it is identified as a layered precipitation echo.

[0154] According to embodiments of this disclosure, the radar scanning data is obtained by traversing all azimuth angles;

[0155] The judgment module 520 includes:

[0156] The number of third-range reservoirs containing valid precipitation echoes in the radar scan data is counted.

[0157] The azimuth angle with the largest third distance value is selected as the first position;

[0158] Adjust the azimuth angle of the radar to the first position.

[0159] According to embodiments of this disclosure, the antenna has multiple deflection angles, and the deflection angles of the multiple antennas are adjusted in preset steps with the antenna's normal direction as the center.

[0160] According to embodiments of this disclosure, the determining module 550 includes:

[0161] The observation data of the area scanned in the normal direction of the antenna is taken as the true value;

[0162] After adjusting the elevation angle and deflection angle of the antenna, calculate the difference between at least two observation data points that overlap with the area scanned in the normal direction of the antenna and the true value;

[0163] Determine whether the average value of the difference is greater than the preset threshold. If so, calibrate the radar.

[0164] According to embodiments of this disclosure, the calibration of the radar includes:

[0165] The radar was calibrated using the metal ball method.

[0166] This disclosure also discloses an electronic device. Figure 6 A structural block diagram of an electronic device according to an embodiment of the present disclosure is shown.

[0167] like Figure 6 As shown, the electronic device includes a memory and a processor, wherein the memory is used to store one or more computer instructions, wherein the one or more computer instructions are executed by the processor to implement the following method steps:

[0168] Receive radar scan data and identify whether it is a valid precipitation echo;

[0169] If so, the radar azimuth angle is adjusted to the first position according to the radar scanning data;

[0170] At the first position, the elevation angle of the antenna is adjusted to at least two preset angles, and the deflection angle of the antenna is adjusted at each preset angle so that the deflection angle of the antenna at one preset angle is adjusted to overlap with the area scanned by the antenna in the normal direction at another preset angle.

[0171] Receive observation data after adjusting the elevation angle and deflection angle of the antenna;

[0172] Whether to calibrate the radar is determined based on the observation data and a preset threshold.

[0173] The technical solution provided in this disclosure involves receiving and analyzing radar scanning data to identify the presence of valid precipitation echoes. If valid precipitation echoes are present, the radar azimuth angle is adjusted to a first position based on the scanning data. This first position is the optimal azimuth angle calculated from the radar scanning data, ensuring that the scanning beam covers more precipitation echoes. At the first position, the antenna elevation angle is adjusted to at least two preset angles, and the antenna deflection angle is further adjusted at each preset angle so that the antenna deflection angle at one preset angle corresponds to the scanning area at a certain position, while simultaneously overlapping with the scanning area in the normal direction of the antenna at another preset angle. The radar receives the observation data detected by the adjusted antenna elevation and deflection angles. By analyzing the observation data and comparing it with preset thresholds, it determines whether radar calibration is required. If the observation data meets expectations and the deviation is within the preset threshold range, radar calibration is unnecessary; otherwise, if the deviation exceeds the preset threshold, radar calibration is required to ensure the accuracy and stability of the scanning beam, thereby guaranteeing the accuracy and reliability of the observation data. This solves the problem in existing technologies where the timing of calibration for phased array weather radar is uncertain, leading to situations where excessively high calibration frequencies hinder radar observation operations, or excessively low calibration frequencies fail to guarantee the quality of radar observation data.

[0174] According to embodiments of this disclosure, receiving radar scan data and identifying whether it is a valid precipitation echo includes:

[0175] It receives radar scan data and identifies echo types after eliminating non-meteorological echoes;

[0176] If there is no echo, it is identified as a non-valid precipitation echo;

[0177] If the echo type is convective precipitation echo or stratiform precipitation echo, it is identified as a valid precipitation echo.

[0178] According to embodiments of this disclosure, the echo type identification step includes:

[0179] Set the threshold range for vertical cumulative liquid water content and the threshold range for distance from the reservoir;

[0180] The number of first distance reservoirs whose vertical cumulative liquid water content is lower than the lower limit of the vertical cumulative liquid water content threshold range is counted. If the number of first distance reservoirs is lower than the lower limit of the distance reservoir number threshold range, it is identified as an ineffective precipitation echo.

[0181] The number of second-distance reservoirs whose vertical cumulative liquid water content is higher than the upper limit of the threshold range of vertical cumulative liquid water content is counted. If the number of second-distance reservoirs is higher than the upper limit of the threshold range of the number of distance reservoirs, it is identified as a convective precipitation echo.

[0182] If the first distance reservoir number is not lower than the lower limit of the distance reservoir number threshold range and the second distance reservoir number is not higher than the upper limit of the distance reservoir number threshold range, then it is identified as a layered precipitation echo.

[0183] According to embodiments of this disclosure, the radar scanning data is obtained by traversing all azimuth angles;

[0184] The step of adjusting the radar azimuth to the first position based on the radar scanning data includes:

[0185] The number of third-range reservoirs containing valid precipitation echoes in the radar scan data is counted.

[0186] The azimuth angle with the largest third distance value is selected as the first position;

[0187] Adjust the azimuth angle of the radar to the first position.

[0188] According to embodiments of this disclosure, the antenna has multiple deflection angles, and the deflection angles of the multiple antennas are adjusted in preset steps with the antenna's normal direction as the center.

[0189] According to embodiments of this disclosure, determining whether to calibrate the radar based on the observation data and a preset threshold includes:

[0190] The observation data of the area scanned in the normal direction of the antenna is taken as the true value;

[0191] After adjusting the elevation angle and deflection angle of the antenna, calculate the difference between at least two observation data points that overlap with the area scanned in the normal direction of the antenna and the true value;

[0192] Determine whether the average value of the difference is greater than the preset threshold. If so, calibrate the radar.

[0193] According to embodiments of this disclosure, the calibration of the radar includes:

[0194] The radar was calibrated using the metal ball method.

[0195] Figure 7 A schematic diagram of the structure of a computer system suitable for implementing the method according to embodiments of the present disclosure is shown.

[0196] like Figure 7 As shown, the computer system includes a processing unit that can execute various methods described above based on a program stored in a read-only memory (ROM) or a program loaded from a storage portion into a random access memory (RAM). The RAM also stores various programs and data required for the operation of the computer system. The processing unit, ROM, and RAM are interconnected via a bus. Input / output (I / O) interfaces are also connected to the bus.

[0197] The following components are connected to the I / O interface: input sections including keyboards, mice, etc.; output sections including cathode ray tubes (CRTs), liquid crystal displays (LCDs), and speakers; storage sections including hard disks, etc.; and communication sections including network interface cards such as LAN cards and modems. The communication section performs communication processes via a network such as the Internet. Drives are also connected to the I / O interface as needed. Removable media, such as disks, optical disks, magneto-optical disks, semiconductor memories, etc., are installed on the drive as needed so that computer programs read from them can be installed into the storage section as needed. The processing unit can be implemented as a CPU, GPU, TPU, FPGA, NPU, etc.

[0198] In particular, according to embodiments of this disclosure, the methods described above can be implemented as computer software programs. For example, embodiments of this disclosure include a computer program product comprising a computer program tangibly embodied on a machine-readable medium, the computer program containing program code for performing the methods described above. In such embodiments, the computer program can be downloaded and installed from a network via a communication component, and / or installed from a removable medium.

[0199] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0200] The units or modules described in the embodiments of this disclosure can be implemented in software or programmable hardware. The described units or modules can also be located in a processor, and the names of these units or modules do not necessarily constitute a limitation on the unit or module itself.

[0201] In another aspect, this disclosure also provides a computer-readable storage medium, which may be a computer-readable storage medium included in the electronic device or computer system described above; or it may be a standalone computer-readable storage medium not assembled into a device. The computer-readable storage medium stores one or more programs, which are used by one or more processors to perform the methods described in this disclosure.

[0202] The above description is merely a preferred embodiment of this disclosure and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this disclosure is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features disclosed in this disclosure that have similar functions.

Claims

1. A method of monitoring the deviation of a phased array weather radar scanning beam, characterized in that, The method comprises: receiving radar scanning data and identifying whether it is a valid precipitation echo; if yes, adjusting the azimuth angle of the radar to a first position according to the radar scanning data, the first position being the optimal azimuth angle calculated according to the radar scanning data; at the first position, adjusting the elevation angle of the antenna to at least two preset angles, and adjusting the deflection angle of the antenna at each preset angle, so that the deflection angle of the antenna at one preset angle is adjusted to a position scanning area, which overlaps with the area scanned by the normal direction of the antenna at another preset angle; receiving observation data after adjusting the elevation angle of the antenna and the deflection angle of the antenna; determining whether to calibrate the radar according to the observation data and a preset threshold.

2. The monitoring method according to claim 1, characterized in that, The receiving radar scanning data and identifying whether it is a valid precipitation echo comprises: receiving radar scanning data and identifying the echo type after eliminating non-meteorological echoes; if there is no echo, it is identified as a non-valid precipitation echo; if the echo type is a convective precipitation echo or a stratiform precipitation echo, it is identified as a valid precipitation echo.

3. The monitoring method of claim 2, wherein, The echo type identification step comprises: setting a vertical integrated liquid water content threshold range and a distance bin threshold range; counting a first distance bin number of the vertical integrated liquid water content lower than the lower limit of the vertical integrated liquid water content threshold range, and if the first distance bin number is lower than the lower limit of the distance bin threshold range, it is identified as a non-valid precipitation echo; counting a second distance bin number of the vertical integrated liquid water content higher than the upper limit of the vertical integrated liquid water content threshold range, and if the second distance bin number is higher than the upper limit of the distance bin threshold range, it is identified as a convective precipitation echo; if the first distance bin number is not lower than the lower limit of the distance bin threshold range and the second distance bin number is not higher than the upper limit of the distance bin threshold range, it is identified as a stratiform precipitation echo.

4. The monitoring method according to any one of claims 1 to 3, characterized in that, The radar scanning data is obtained after traversing all azimuth angles; The adjusting the azimuth angle of the radar to a first position according to the radar scanning data comprises: counting a third distance bin number of the radar scanning data in which the valid precipitation echo exists; selecting the azimuth angle with the largest third distance bin number as the first position; adjusting the azimuth angle of the radar to the first position.

5. The monitoring method according to claim 4, wherein the deflection angle of the antenna is provided with multiple, and the multiple deflection angles of the antenna are centered on the normal direction of the antenna and adjusted according to a preset step. The determining whether to calibrate the radar according to the observation data and a preset threshold comprises:

6. The monitoring method of claim 1, wherein, taking the observation data of the area scanned by the normal direction of the antenna as the true value; after adjusting the elevation angle of the antenna and the deflection angle of the antenna, calculating the difference between at least two observation data and the true value, which overlap with the area scanned by the normal direction of the antenna; judging whether the average value of the difference is greater than the preset threshold, and if yes, calibrating the radar. The calibrating the radar comprises:

7. The monitoring method of claim 1, wherein, calibrating the radar by using the metal ball method. The method comprises:

8. A device for monitoring the deviation of a scanning beam of a phased array weather radar, characterized in that an identification module configured to receive radar scanning data and identify whether it is a valid precipitation echo; ​ a judging module configured to, if yes, adjust an azimuth angle of the radar to a first position according to the radar scan data, the first position being an optimal azimuth angle calculated according to the radar scan data; an adjusting module configured to, at the first position, adjust an elevation angle of the antenna to at least two preset angles, and at each preset angle, adjust a deflection angle of the antenna, so that a region scanned by the deflection angle of the antenna at one preset angle overlaps with a region scanned by a normal direction of the antenna at another preset angle; a receiving module configured to receive observation data after the elevation angle of the antenna and the deflection angle of the antenna are adjusted; a determining module configured to determine whether to calibrate the radar according to the observation data and a preset threshold.

9. An electronic device, comprising: a memory and a processor; wherein the memory is configured to store one or more computer instructions; and wherein the one or more computer instructions, when executed by the processor, implement the method steps of any one of claims 1-7.

10. A computer readable storage medium having stored thereon computer instructions, wherein, The computer instructions, when executed by the processor, implement the method steps of any one of claims 1-7.

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