Information processing device, information processing method, program, and radar system

Abstract

To provide an information processing device, an information processing method, a program and a radar system capable of estimating precipitation intensity with high accuracy and high resolution.SOLUTION: An information processing device according to an embodiment processes data from a single polarization radar and a dual polarization radar existing at positions different from each other. The information processing device includes: a first acquisition unit for acquiring dual polarization data from the dual polarization radar; a second acquisition unit for acquiring single-polarization data from the single polarization radar; and a processing unit for processing the dual polarization data and the single-polarization data. The processing unit estimates a first precipitation intensity and a first precipitation attenuation from the double polarization data, estimates a second precipitation attenuation from the single polarization data, corrects the single polarization data using the first or second precipitation attenuation, estimates a second precipitation intensity from the corrected single polarization data, and combines the first precipitation intensity and the second precipitation intensity using the spatial resolution of the first precipitation intensity and the spatial resolution of the second precipitation intensity.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] An embodiment of the present invention relates to an information processing device, an information processing method, a program, and a radar system that analyze weather radar data. [Background technology]

[0002] Due to recent climate change, large-scale flood disasters caused by localized torrential rains and tornadoes have become a social issue. Weather radars are installed to predict the occurrence of flood disasters. There are two main types of weather radars: single polarization and dual polarization.

[0003] A single-polarized weather radar (hereafter referred to as single-polarized radar) transmits and receives radio waves (horizontally polarized waves). The intensity of the reflected waves is used to estimate precipitation intensity (amount of precipitation per unit time). Because the intensity of the reflected waves is attenuated by precipitation, the accuracy of precipitation intensity estimation by single-polarized radar is low. Single-polarized radar is easy to manufacture and has low manufacturing costs.

[0004] Dual polarized weather radar (hereafter referred to as dual polarized radar) transmits and receives two radio waves, one horizontally polarized and one vertically polarized. One method for estimating precipitation intensity with dual polarized radar is to use the phase difference between the received signals of the two polarized waves. Since the phase difference is not easily affected by precipitation attenuation, dual polarized radar has high estimation accuracy for precipitation intensity. Dual polarized radar requires advanced technology for power calibration and phase alignment between the polarized waves.

[0005] A meteorological observation system that uses both single-polarized and dual-polarized radars has been developed. Either dual-polarized or single-polarized radar data is selected depending on the estimation location, and the precipitation intensity is estimated from the selected data.

[0006] In order to improve the quality of single-polarized radar, it is effective to use dual-polarized radar in combination, but since the spatial resolution of the estimated value is high near the radar installation point, if single-polarized radar data is selected with an emphasis on spatial resolution, the accuracy of the estimation of precipitation intensity will be sacrificed. It is difficult to estimate precipitation intensity with high accuracy and high spatial resolution by simply selecting dual-polarized radar or single-polarized radar depending on the estimation point. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2006-30013 A Summary of the Invention [Problem to be solved by the invention]

[0008] An object of the present invention is to provide an information processing device, an information processing method, a program, and a radar system that are capable of estimating precipitation intensity with high accuracy and high spatial resolution. [Means for solving the problem]

[0009] An information processing device according to an embodiment processes data from a single polarized radar and a dual polarized radar that are located at different positions. The information processing device includes a first acquisition unit that acquires dual polarized data from the dual polarized radar, a second acquisition unit that acquires single polarized data from the single polarized radar, and a processing unit that processes the dual polarized data and the single polarized data. The processing unit estimates a first precipitation intensity from the dual polarized data, estimates a first precipitation attenuation from the dual polarized data, estimates a second precipitation attenuation from the single polarized data, corrects the single polarized data using the first precipitation attenuation or the second precipitation attenuation, estimates the second precipitation intensity from the corrected single polarized data, and combines the first precipitation intensity and the second precipitation intensity using a spatial resolution of the first precipitation intensity and a spatial resolution of the second precipitation intensity. [Brief description of the drawings]

[0010] [Figure 1]FIG. 1 is a block diagram illustrating an example of an information processing apparatus according to a first embodiment. [Diagram 2] FIG. 2 is a block diagram for explaining an example of a processing unit according to the first embodiment. [Diagram 3] FIG. 11 is a block diagram for explaining an example of a processing unit according to the second embodiment. [Figure 4] FIG. 13 is a block diagram for explaining an example of a processing unit according to the third embodiment. [Diagram 5] FIG. 13 is a block diagram for explaining an example of a processing unit according to the fourth embodiment. [Figure 6] FIG. 13 is a block diagram illustrating an example of a processing unit according to the fifth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, the embodiments will be described with reference to the drawings. The following description is an example of an apparatus and method for embodying the technical idea of ​​the embodiment, and the technical idea of ​​the embodiment is not limited to the structure, shape, arrangement, material, etc. of the components described below. Modifications that a person skilled in the art can easily conceive are naturally included in the scope of the disclosure. In order to make the description clearer, the size, thickness, planar dimensions, or shape of each element may be changed from the actual embodiment and shown diagrammatically. Elements having different dimensional relationships or ratios may be included in multiple drawings. In multiple drawings, corresponding elements may be given the same reference numerals and duplicated descriptions may be omitted. Some elements may be given multiple names, but these examples of names are merely examples and do not deny the use of other names for these elements. In addition, it is not denied that elements not given multiple names may be given other names. In the following description, "connection" may include not only direct connection but also connection via other elements.

[0012] First embodiment 1 is a block diagram for explaining an example of an information processing system including an information processing device 10 according to a first embodiment. The information processing system includes a first database 2, a second database 4, a dual polarized radar 6, a single polarized radar 8, and the information processing device 10. The information processing device 10 basically analyzes data from the single polarized radar 8, but also analyzes data from the dual polarized radar 6 to improve precision (accuracy).

[0013] The weather radar measures the amount of precipitation falling in an area surrounded by distances r and r+ΔR from the radar, elevation angles θ and θ+Δθ, and azimuth angles φ and φ+Δφ by radio wave reflection. Δ represents the observation resolution. For convenience of expression, the above-mentioned area becomes larger as the distance increases, even if θ, Δθ, φ, and Δφ are given values. In other words, when observing near the radar, observation is possible with fine resolution, but when observing far from the radar, observation is performed with coarse resolution. In this specification, this resolution is called spatial resolution. The embodiment aims to realize high-quality observation with fine spatial resolution even at a long distance.

[0014] The information processing device 10 is connected to a first database 2 and a second database 4. The first database 2 is connected to a dual polarized radar 6. The dual polarized radar 6 is equipped with a rotating antenna and a transmission / reception circuit, and transmits and receives horizontally polarized waves and vertically polarized waves in an observation range with a radius of tens to hundreds of kilometers centered on the installation location. The dual polarized radar 6 outputs dual polarized data according to the reflected waves. The dual polarized data is polar coordinate data with the position of the dual polarized radar 6 as the origin. The first database 2 stores the dual polarized data.

[0015] Examples of dual polarization data are radar reflectivity factor Z and inter-polarization phase difference Φ dp , the rate of change in the phase difference between the polarizations K dp , radar reflectivity factor difference Z dr and the inter-polarization correlation coefficient ρ hvThe radar reflectivity factor Z is calculated from the strength of the horizontally polarized reflected wave (average received power). The radar reflectivity factor Z is related to the precipitation intensity observed on the ground. The inter-polarization phase difference Φ, which is the phase difference between the horizontally polarized reflected wave and the vertically polarized reflected wave, is dp is related to the precipitation intensity. dp The precipitation intensity calculated based on is more accurate than the precipitation intensity calculated based on the radar reflectivity factor Z. dp represents the rate of change per distance between the phase difference between the horizontally polarized reflected wave and the vertically polarized reflected wave. The radar reflectivity factor difference Z dr represents the difference in scattering strength of radio waves due to the flatness of the scatterer, and is used to calculate precipitation intensity and determine the shape of scatterers (raindrops, snow, ice crystals, etc.). The inter-polarized correlation coefficient ρ, which is the correlation coefficient between the reflected wave of horizontal polarization and the reflected wave of vertical polarization, hv represents the uniformity of the scatterer.

[0016] The second database 4 is connected to the single polarized radar 8. The single polarized radar 8 is equipped with a rotating antenna and a transmission / reception circuit, and transmits and receives horizontally polarized waves in an observation range of a radius of tens to hundreds of kilometers centered on the installation location. One or more single polarized radars 8 are placed at points in the observation range of the dual polarized radar 6. The single polarized radar 8 and the dual polarized radar 6 are placed in different positions from each other. The single polarized radar 8 outputs a radar reflection factor Z. The radar reflection factor Z is polar coordinate data with the position of the single polarized radar 8 as the origin. The second database 4 stores the radar reflection factor Z.

[0017] The information processing device 10 processes the dual polarization data of each point in the observation range stored in the first database 2 and the radar reflectivity factor Z of each point stored in the second database 2, and estimates the precipitation intensity (mm / time) of each point in the observation range of the single polarization radar 8. An example of an estimated point is a lattice point of xy coordinates in the observation range.

[0018] The information processing device 10 includes a first acquisition unit 12, a second acquisition unit 14, a processing unit 16, and an output unit 18. The first acquisition unit 12 is connected to the first database 2. The first acquisition unit 12 acquires dual polarization data from the first database 2 and supplies the dual polarization data to the processing unit 16. The second acquisition unit 14 is connected to the second database 4. The second acquisition unit 14 acquires a radar reflection factor Z from the second database 4 and supplies the radar reflection factor Z to the processing unit 16. The processing unit 16 performs arithmetic processing on the dual polarization data and the radar reflection factor Z, and supplies the processing result to the output unit 18.

[0019] The processing unit 16 includes a CPU 22, a storage 24, and a memory 26. The CPU 22, the storage 24, and the memory 26 are connected to a bus line 28. The first acquisition unit 12, the second acquisition unit 14, and the output unit 18 are also connected to the bus line 28. The storage 24 stores a calculation processing program for the processing unit 16. The CPU 22 executes the calculation processing program. The memory 26 stores data during calculation processing. The processing unit 16 is implemented in software by the CPU 22 executing the calculation processing program.

[0020] 1 shows the first database 2, the second database 4, the dual polarized radar 6, the single polarized radar 8, and the information processing device 10 as separate entities, but some of these may comprise some of the others. For example, the dual polarized radar 6 may comprise at least a part of the first database 2 and / or the information processing device 10. The single polarized radar 8 may comprise at least a part of the second database 4 and / or the information processing device 10. The information processing device 10 may comprise the first database 2 and the second database 4.

[0021] FIG. 1 shows the first database 2 for the dual polarization radar 6 and the second database 4 for the single polarization radar 8 separately, but instead of providing two databases, a single database may be provided to store data for the two radars.

[0022] 2 is a block diagram for explaining an example of the processing unit 16 according to the first embodiment. The processing unit 16 includes a coordinate conversion unit 32, a first precipitation intensity estimator 34, a first attenuation estimator 36, a second attenuation estimator 42, a priority information generator 44, an attenuation corrector 48, a second precipitation intensity estimator 52, and a combiner 56.

[0023] The processing unit 16 may be implemented by a plurality of hardware blocks that realize the respective functional blocks shown in Fig. 2, instead of being implemented in software by the CPU 22. The processing unit 16 is not limited to having one CPU 22, but may have a plurality of CPUs that respectively realize the plurality of functional blocks.

[0024] The coordinate conversion unit 32 is connected to the first acquisition unit 12. The coordinate conversion unit 32 converts the coordinates of the dual polarization data acquired by the first acquisition unit 12 so that the coordinates of the single polarization data and the dual polarization data of the same point become the same coordinates. This compensates for the difference in position between the single polarization radar and the dual polarization radar. The coordinate conversion unit 32 may be connected to the second acquisition unit 14 instead of the first acquisition unit 12. In this case, the coordinate conversion unit 32 converts the coordinates of the single polarization data so that the coordinates of the single polarization data and the dual polarization data of the same point become the same coordinates. Furthermore, the coordinate conversion unit 32 may be connected to the first acquisition unit 12 and the second acquisition unit 14. In this case, the coordinate conversion unit 32 converts the coordinates of the single polarization data and the dual polarization data so that the coordinates of the single polarization data and the dual polarization data of the same point become the same coordinates.

[0025] The first precipitation intensity estimation unit 34 estimates the precipitation intensity (referred to as the first precipitation intensity) at each point in the observation range of the dual polarization radar 6 from the dual polarization data output from the coordinate conversion unit 32. The first precipitation intensity is supplied to a first input terminal of the synthesis unit 56.

[0026] The first attenuation estimation unit 36 ​​estimates the attenuation due to precipitation (precipitation attenuation) of the radar reflectivity factor in the single-polarized radar from the dual-polarized data output from the coordinate conversion unit 32. Details of the attenuation estimation will be described later with reference to Equations 4, 5, and 8. The estimate by the first attenuation estimation unit 36 ​​(referred to as a first precipitation attenuation estimate value) is supplied to an attenuation correction unit 48.

[0027] The second attenuation estimation unit 42 is connected to the second acquisition unit 14. The second attenuation estimation unit 42 estimates precipitation attenuation of the radar reflection factor in the single-polarized radar from the radar reflection factor acquired by the second acquisition unit 14. The estimated value by the second attenuation estimation unit 42 (referred to as a second precipitation attenuation estimated value) is supplied to the attenuation correction unit 48.

[0028] The attenuation correction unit 48 corrects the radar reflectivity factor to compensate for the precipitation attenuation using the first precipitation attenuation estimate value and the second precipitation attenuation estimate value. The output of the attenuation correction unit 48 is provided to a second precipitation intensity estimator 52.

[0029] The second precipitation intensity estimation unit 52 estimates the precipitation intensity (referred to as the second precipitation intensity) at each point in the observation range of the single-polarized radar 8 from the radar reflectivity factor Z compensated for precipitation attenuation. The second precipitation intensity is supplied to a second input terminal of the synthesis unit 56.

[0030] The priority information generator 44 is connected to the coordinate converter 32 and the second acquirer 14. The priority information generator 44 generates priority information for each of the single polarized radar and the dual polarized radar according to the spatial resolution calculated from the distance from the radar and the beam width, the blind area due to the location, etc. The priority information generator 44 supplies the priority information for the single polarized radar and the priority information for the dual polarized radar to the combiner 56.

[0031] The synthesis unit 56 synthesizes the first precipitation intensity and the second precipitation intensity at a ratio according to the priority information. The precipitation intensity synthesized by the synthesis unit 56 is supplied to the output unit 19. If the ratio of one precipitation intensity is 0, the synthesis unit 56 outputs only the other precipitation intensity. Synthesis by the synthesis unit 56 also includes selection.

[0032] The output unit 18 outputs the composite precipitation intensity. Examples of the form of output include a screen display, printing in list form, and transmission to another device.

[0033] According to the information processing device 10 of the first embodiment, the attenuation correction unit 48 accurately corrects the radar reflectivity factor attenuated by precipitation using the first precipitation attenuation estimated value and the second precipitation attenuation estimated value. The second precipitation intensity estimation unit 52 accurately estimates the second precipitation intensity from the corrected radar reflectivity factor. The synthesis unit 56 synthesizes the second precipitation intensity and the first precipitation intensity according to the priority information of the single polarization radar and the priority information of the dual polarization radar. This compensates for precipitation attenuation while maintaining high spatial resolution, and the precipitation intensity is estimated with high accuracy and spatial resolution.

[0034] The processing unit 16 will now be described in detail.

[0035] Received power P expressed in polar coordinates r (r,θ,Φ) and the radar reflectivity factor Z expressed in polar coordinates m The relationship between (r, θ, Φ) [dBZ] is shown in formula (1). r is the distance between the radar installation point and the estimated point. θ is the elevation angle of the estimated point, and Φ is the azimuth angle of the estimated point. C is the radar constant, which is calculated from radar parameters such as antenna gain. |K| 2 represents the dielectric constant of the raindrop. An experimentally obtained constant is used as the dielectric constant of the raindrop. The radar reflectivity factor Z m m represents the measured value. Radar reflectivity factor Z m is the attenuated value due to precipitation attenuation. The single-polarized radar 8 calculates the received power P r The radar reflectivity factor Z m Convert to.

[0036]

number

[0037] The radar reflectivity factor has long been used to estimate precipitation intensity based on the received power. The radar reflectivity factor Z(r,θ,Φ)[dBZ] is expressed by the raindrop diameter D and the size distribution N(D,r,θ,Φ) as shown in formula (2). The radar reflectivity factor Z(r,θ,Φ) is a value that is not affected by precipitation attenuation.

[0038]

number

[0039] Actual observed radar reflectivity factor Z m (r, θ, Φ) is subjected to precipitation attenuation κ(s) [dB / km] and is expressed by equation (3).

[0040]

number

[0041] The second attenuation estimation unit 42 estimates the radar reflection factor Z m Using the precipitation attenuation calculation parameters a and b from (r, θ, Φ), the second precipitation attenuation estimate A Z Calculate (r,θ,Φ) [dB / km]. There are several methods for estimating precipitation attenuation. Examples of estimation methods include the Hitschfeld-Bordan solution (Equation 4) and the FV (Final Value) solution (Equation 5).

[0042]

number

[0043] J(r r ,θ,Φ) and J(r,θ,Φ) have different ranges. The FV solution is a method to calculate precipitation attenuation from the observation end (the farthest point in the observation range), and r r >r. r r indicates the end of the observation range (the farthest point from the radar).

[0044] Equation (7) expresses the precipitation attenuation A f The precipitation attenuation at the observation end A fcontains the radar reflectivity factor Z(r,θ,Φ) that is not affected by precipitation attenuation. In practice, the radar reflectivity factor Z(r,θ,Φ) is obtained from a microwave radiometer or other device. In the Hitschfeld-Bordan method of equation (4), the solution (second precipitation attenuation estimate) is prone to divergence at the observation end during heavy rain. The FV (Final Value) method makes it easier to obtain a stable solution. The FV method requires additional equipment to calculate the precipitation attenuation at the observation end. Depending on the accuracy of the equipment, the FV solution may have a lower accuracy in estimating rain attenuation than the HB solution.

[0045] The coordinate conversion unit 32 converts the coordinates of the dual polarization data into the coordinates of the laser reflectivity factor so that the processing unit 16, which mainly processes the radar reflectivity factor, can also process the dual polarization data, and so that the same point can be recognized as the same point (same coordinates) in the radar reflectivity factor and the dual polarization data. The coordinate conversion unit 32 may directly convert the polar coordinates of the dual polarization data into the polar coordinates of the laser reflectivity factor. The coordinate conversion unit 32 may convert the polar coordinates of the dual polarization data into a grid-like orthogonal coordinate of predefined latitude, longitude, and altitude, and then convert the orthogonal coordinates into the polar coordinates of the laser reflectivity factor. The coordinate conversion unit 32 may convert the polar coordinates of the dual polarization data by the Cressman method (e.g., the Cressman interpolation method). When the distance between a data point and the coordinates of the single polarization data is the greatest, the coordinate conversion unit 32 may replace the coordinates of the corresponding data point (dual polarization data) with the coordinates of the single polarization data.

[0046] The first attenuation estimation unit 36 ​​estimates precipitation attenuation from the dual polarization data after the coordinate transformation. The first attenuation estimation unit 36 ​​estimates the inter-polarization phase difference change rate K dp Using (r, θ, Φ), the precipitation attenuation A is calculated as shown in equation (8). MP (r,θ,Φ) may be estimated. ah1 and ah2 are precipitation intensity conversion coefficients and vary with frequency and elevation angle.

[0047]

number

[0048] The attenuation correction unit 48 corrects the observation range of the dual-polarized radar and the inter-polarized phase difference change rate K dp For regions where (r, θ, Φ) is highly reliable, A in equation (8) MP A Z,MP For other areas, the attenuation correction unit 48 corrects the radar reflectivity factor by using the formula (9) so as to compensate for the precipitation attenuation. Z A Z,MP Then, the radar reflectivity factor is corrected using equation (9). This correction compensates for precipitation attenuation.

[0049]

number

[0050] The second precipitation rate estimation unit 52 calculates the second precipitation rate R from the corrected radar reflectivity factor (equation (9)) using the precipitation rate calculation parameters B and β as shown in equation (10). Z Estimate (n) [mm / h].

[0051]

number

[0052] On the other hand, the first precipitation intensity estimation unit 34 estimates the precipitation intensity from the dual polarization data. The first precipitation intensity estimation unit 34 estimates the precipitation intensity from the dual polarization data based on the inter-polarization phase difference change rate K dp Using (r, θ, Φ), the first precipitation intensity R is calculated as shown in equation (11). MP (r,θ,Φ) may be estimated. The first precipitation intensity R MP (r,θ,Φ) are estimated with high accuracy.α1,α2 are precipitation intensity coefficients and vary with frequency and elevation angle.

[0053]

number

[0054] The priority information generating unit 44 generates priority information indicating the priority of the estimated value of precipitation intensity by the dual polarization radar 6 and priority information indicating the priority of the estimated value of precipitation intensity by the single polarization radar 8. The priority may be determined according to the spatial resolution of the estimated value. The spatial resolution is calculated according to the distance from the installation point of the radar and the beam width.

[0055] The synthesis unit 56 adds and synthesizes the first precipitation intensity and the second precipitation intensity with a weight according to the priority. The spatial resolution of the second precipitation intensity is d Z , the resolution of the first precipitation intensity is d MP In this case, the weight of the second precipitation intensity w Z is 1 / d Z , the second precipitation intensity weight w MP is 1 / d MP The higher the spatial resolution, the smaller the resolution value and the larger the weighting value. final Estimate (r,θ,Φ).

[0056]

number

[0057] One or more single-polarized radars are installed within the observation range of the dual-polarized radar. The distance between an observation point within the observation range of the single-polarized radar and the installation point of the dual-polarized radar is longer than the distance between the observation point and the installation point of the single-polarized radar. At this observation point, the spatial resolution of the first precipitation intensity based on the dual-polarized data is lower than the spatial resolution of the second precipitation intensity based on the radar reflectivity factor. According to equation (12), the second precipitation intensity contributes more to the composite precipitation intensity at this observation point than the first precipitation intensity. Since the radar reflectivity factor is corrected according to the first precipitation attenuation or the second precipitation attenuation, the accuracy of the second precipitation intensity is high. Therefore, according to the synthesis of equation (12), the precipitation intensity is estimated with high accuracy and high spatial resolution.

[0058] The priority information generating unit 44 may generate priority information according to not only spatial resolution but also blind areas due to structures that block radio waves and clutter noise. The priority of the estimated value of precipitation intensity by a radar having a blind area may be low. The priority of the estimated value of precipitation intensity by a radar with a lot of clutter noise may be low. Whether or not there is a radio wave blocking object in the observation range depends on the positions of the radars 6, 8 relative to the observation range. The presence or absence of clutter noise also depends on the positions of the radars 6, 8 relative to the observation range. The priority information generating unit 44 can generate priority information according to the positions of the radars 6, 8 relative to the observation range.

[0059] The weights used by the synthesis unit 56 do not have to be continuously changing values, but may be binary values ​​of 0 and 1. For example, when the weight of the estimated value of precipitation intensity with low spatial resolution is 0, the synthesis unit 56 outputs the estimated value of precipitation intensity with high spatial resolution as is.

[0060] According to the first embodiment, the first precipitation attenuation is estimated from the dual polarization data obtained by the dual polarization radar, and the second precipitation attenuation is estimated from the radar reflectivity factor obtained by the single polarization radar. The radar reflectivity factor is corrected according to the first precipitation attenuation or the second precipitation attenuation, and the second precipitation intensity estimated from the radar reflectivity factor is highly accurate. The first precipitation intensity estimated from the dual polarization data and the second precipitation intensity estimated from the corrected radar reflectivity factor are synthesized using spatial resolution, blind area, clutter noise, etc. Therefore, in an area where the spatial resolution of the second precipitation intensity is high, a synthesized precipitation intensity with a large contribution of the second precipitation intensity is obtained. Therefore, a synthesized precipitation intensity with improved estimation accuracy is obtained while maintaining high spatial resolution is obtained.

[0061] The synthetic precipitation intensity according to the first embodiment may be applied to a precipitation observation system, a precipitation forecast system, a snowfall / hailfall forecast system, etc. This makes it possible to realize a system that improves the observation accuracy and forecast accuracy while maintaining high spatial resolution.

[0062] Second embodiment According to the first embodiment, it is possible to improve the estimation accuracy while maintaining high resolution. On the other hand, the estimated value of the second precipitation intensity based on the radar reflectivity factor varies depending on the particle size distribution. The same estimated value may be obtained even for different precipitation intensities. Therefore, depending on the precipitation state, an overall strong / weak bias occurs in the estimated value of the second precipitation intensity. The second embodiment aims to suppress the bias of the estimated value of the second precipitation intensity by using the first precipitation intensity estimated from dual polarization data.

[0063] 3 is a block diagram for explaining an example of the processing unit 16 according to the second embodiment. In the second embodiment, a precipitation intensity correction unit 54 is added to the processing unit 16 of the first embodiment. The output of the first precipitation intensity estimation unit 34 and the output of the second precipitation intensity estimation unit 52 are supplied to the precipitation intensity correction unit 54. The precipitation intensity correction unit 54 calculates a first precipitation intensity R MP Second precipitation rate R based on (r,θ,Φ) and radar reflectivity factor Z Using the correction coefficient κ that expresses the level relationship of (r,θ,Φ), the second precipitation intensity R Z (r,θ,Φ) is corrected and the corrected precipitation rate R corr (r, θ, Φ) is calculated. The correction coefficient κ may be defined as the total rainfall ratio.

[0064]

number

[0065] The first precipitation rate estimated from the dual polarization data has a small bias. Therefore, by correcting the second precipitation rate estimated from the radar reflectivity factor using the first precipitation rate, the bias of the second precipitation rate can be suppressed.

[0066] Equation (13) shows a uniform correction coefficient κ. The radar reflectivity factors may be divided into a number of groups according to their values, and a different correction coefficient may be set for each group of radar reflectivity factors.

[0067] According to the second embodiment, even if the radar reflectivity factor varies depending on the particle size distribution, an unbiased estimate of the second precipitation rate can be obtained.

[0068] Third embodiment The estimation accuracy of the second precipitation attenuation based on the radar reflectivity factor is inferior to the estimation accuracy of the first precipitation attenuation based on the dual polarization. In the first and second embodiments, the radar reflectivity factor is corrected using the estimated value of the first precipitation attenuation as well, thereby avoiding deterioration of the estimation accuracy of the second precipitation attenuation. However, when the observation range of the dual polarization radar and the observation range of the single polarization radar do not overlap, the estimated value of the first precipitation attenuation cannot be used to correct the radar reflectivity factor. The third embodiment aims to improve the estimation accuracy itself of the second precipitation attenuation based on the radar reflectivity factor. The third embodiment is considered to be effective in an area where the observation range of the dual polarization radar and the observation range of the single polarization radar do not overlap.

[0069] FIG. 4 is a block diagram for explaining an example of the processing unit 16 according to the third embodiment. In the third embodiment, a parameter optimization unit 46 is added to the processing unit 16 of the first or second embodiment (FIG. 4 shows the processing unit 16 of the second embodiment). m (r, θ, Φ) and the first precipitation attenuation estimate A from the first attenuation estimation unit 36 MP (r, θ, Φ) is supplied to the parameter optimization unit 46. The parameter optimization unit 46 optimizes the precipitation attenuation calculation parameters a and b used for estimation by the second attenuation estimation unit 42 based on the highly accurate first precipitation attenuation estimation value A MP (r,θ,Φ) and the second precipitation attenuation estimate A shown in equation (4) or (5). Z Optimize using an optimization method such as the least squares method so that the difference with (r, θ, Φ) is minimized.

[0070] Another example of the optimization method of the parameter optimization unit 46 is the radar reflectivity factor Z m (r, θ, Φ) is the input data, and the A of the same area is calculated using equation (8). MPThis is a method of calculating precipitation attenuation calculation parameters a and b using a machine learning model with (r, θ, Φ) as training data. The machine learning model may be provided in the information processing device 10 or may be provided separately from the information processing device 10. The machine learning model is a method of calculating the precipitation attenuation calculation parameters a and b using a machine learning model with (r, θ, Φ) as training data. m Input (r, θ, Φ) and output precipitation attenuation calculation parameters a and b.

[0071] According to the third embodiment, the second precipitation attenuation A Z Since the estimation accuracy of (r,θ,Φ) itself is improved, precipitation intensity can be estimated with high spatial resolution and accuracy even in areas where the observation ranges of the dual-polarized radar and the single-polarized radar do not overlap.

[0072] Fourth embodiment FIG. 5 is a block diagram for explaining an example of the processing unit 16 according to the fourth embodiment. In the fourth embodiment, the first attenuation estimation unit 36 ​​is removed from the processing unit 16 of the first or second embodiment (FIG. 5 shows the processing unit 16 of the second embodiment), and a radar reflectivity factor generation unit 72, an attenuation integral value estimation unit 74, and a precipitation attenuation vs. radar reflectivity factor relationship estimation unit 76 are added. The output of the first precipitation intensity estimation unit 34 is supplied to the radar reflectivity factor generation unit 72. The output of the radar reflectivity factor generation unit 72 is supplied to the attenuation integral value estimation unit 74. The output of the attenuation integral value estimation unit 74 is supplied to the precipitation attenuation vs. radar reflectivity factor relationship estimation unit 76. The output of the precipitation attenuation vs. radar reflectivity factor relationship estimation unit 76 is supplied to the second attenuation estimation unit 42.

[0073] The radar reflectivity factor generator 72 calculates the radar reflectivity factor Z from the equations (10) and (11) using the highly accurate first precipitation intensity estimate. MP Specifically, the radar reflection factor generator 72 calculates the inter-polarization phase difference change rate K dp , and substitute into equation (11) to obtain the estimated value R MP (r, θ, Φ). The radar reflectivity factor generator 72 calculates the estimated value R MP (r,θ,Φ) is R Z (r, θ, Φ) into equation (10) to obtain the corrected radar reflectivity factor (equation (9)). The corrected radar reflectivity factor (equation (9)) is the radar reflectivity factor ZMP (r,θ,Φ).

[0074]

number

[0075] The attenuation integral value estimation unit 74 estimates the radar reflection factor Z MP (r, θ, Φ) (Equation (15)) and the radar reflectivity factor Z m From the difference of (r,θ,Φ), the estimated integral value of the second precipitation attenuation S Ah Find (r,θ,Φ).

[0076] The precipitation attenuation vs. radar reflectivity factor relationship estimator 76 estimates the precipitation attenuation integral value S Ah (r, θ, Φ) and the radar reflectivity factor Z from the second acquisition unit 14 m The estimation unit 76 estimates the relationship between the distance r from the radar installation point and the radar reflection factor Z m (r) and the polynomial model f(r,Z m (r))=A1r+A2r 2 +…+A N Z m (r)+A M (Z m (r)) 2 and the integral value S of the second precipitation attenuation Ah The polynomial coefficients A1, A2, ... A that minimize the least square error with (r, θ, Φ) N , A M Another example of the estimation method of the precipitation attenuation vs. radar reflectivity factor relationship estimator 76 is to calculate the integral value S Ah Using (r,θ,Φ) as training data and single polarization data and distance from the radar as input data, a machine learning model is used to calculate the polynomial coefficients A1, A2, …A N , A M The machine learning model may be provided within the information processing device 10 or may be provided separately from the information processing device 10.

[0077]

number

[0078] The precipitation attenuation vs. radar reflectivity factor relationship estimator 76 estimates the polynomial coefficients A1, A2, ... A N , A M to the second damping estimation unit 42. The second damping estimation unit 42 calculates a polynomial model f(r,Z m (r)) shows the single polarization data and the polynomial coefficients A1, A2, ... A N , A M Substituting the above, the integral value of the second precipitation attenuation S Ah Find (r,θ,Φ).

[0079] The precipitation attenuation vs. radar reflectivity factor relationship estimator 76 determines polynomial coefficients to correlate highly accurate precipitation attenuation based on dual polarization data with the radar reflectivity factor. Therefore, the second attenuation estimator 42 can estimate precipitation attenuation that takes into account highly accurate precipitation attenuation based on dual polarization data even in a situation where only the radar reflectivity factor is available. The polynomial that estimates the relationship may be expressed by parameters other than the radar reflectivity factor, such as temperature, humidity, and the transmission and reception frequency of the information processing device.

[0080] Fifth embodiment Fig. 6 is a block diagram for explaining an example of the processing unit 16 according to the fifth embodiment. In the fifth embodiment, a precipitation attenuation vs. radar reflectivity factor relationship estimating unit 82 is added to the processing unit 16 of the first or second embodiment (Fig. 5 shows the processing unit 16 of the second embodiment). The precipitation attenuation vs. radar reflectivity factor relationship estimating unit 82 estimates the distance r from the radar installation point and the radar reflectivity factor Z so as to minimize the error of the precipitation attenuation estimated value based on the dual polarization data that is the output of the first attenuation estimating unit 36. m (r) and the polynomial model f(r,Z m (r))=A1r+A2r 2 +…+A N Z m (r)+A M (Z m (r)) 2 Polynomial coefficients A1, A2, … A N , A MAnother example of the estimation method of the precipitation attenuation vs. radar reflectivity factor relationship estimation unit 82 is to directly calculate polynomial coefficients A1, A2, ...A using a machine learning model with the first precipitation attenuation estimate value based on dual polarization data as training data and the single polarization data and the distance from the radar as input data. N , A M The machine learning model may be provided within the information processing device 10 or may be provided separately from the information processing device 10.

[0081] The precipitation attenuation vs. radar reflectivity factor relationship estimator 82 estimates the polynomial coefficients A1, A2, ... A N , A M to the second attenuation estimator 42. The second attenuation estimator 42 receives the single polarization data and the polynomial coefficients A1, A2, ... A N , A M Using the second precipitation attenuation estimate A Z Find (n).

[0082] According to the fifth embodiment, even if the observation area does not overlap with that of the dual polarization radar, the accuracy of precipitation attenuation correction can be improved, and high precipitation intensity estimation can be achieved.

[0083] According to the embodiments, the following information processing device, information processing method, program, and radar system are provided.

[0084] (1) An information processing device for processing data from a single-polarized radar and a dual-polarized radar located at different positions, comprising: A first acquisition unit that acquires dual polarization data from the dual polarization radar; A second acquisition unit that acquires single polarized data from the single polarized radar; a processing unit for processing the dual polarization data and the single polarization data, The processing unit includes: estimating a first precipitation rate from the dual polarization data; estimating a first precipitation attenuation from the dual polarization data; estimating a second precipitation attenuation from the single polarization data; correcting the single polarization data using the first precipitation attenuation or the second precipitation attenuation; estimating a second precipitation rate from the corrected single polarization data; an information processing device that combines the first precipitation intensity and the second precipitation intensity using a spatial resolution of the first precipitation intensity and a spatial resolution of the second precipitation intensity.

[0085] (2) An information processing device as described in (1), wherein the processing unit converts coordinates of at least one of the dual polarization data or the single polarization data so as to correspond between coordinates of the single polarization data indicating a first location and coordinates of the dual polarization data.

[0086] (3) An information processing device according to (1) or (2), The processing unit further uses the position of the single polarization radar and the position of the dual polarization radar to combine the first precipitation intensity and the second precipitation intensity.

[0087] (4) An information processing device according to any one of (1) to (3), The processing unit synthesizes the first precipitation rate R1 and the second precipitation rate R2 using the spatial resolution W1 of the first precipitation rate and the spatial resolution W2 of the second precipitation rate to obtain a synthesized precipitation rate R=(W1R2+W2R1) / (W1+W2).

[0088] (4) An information processing device according to any one of (1) to (4), The processing unit includes: correcting the second precipitation intensity using a ratio between the first precipitation intensity and the second precipitation intensity; The first precipitation rate and the corrected second precipitation rate are combined.

[0089] (6) An information processing device according to any one of (1) to (5), The processing unit includes: determining a calculation parameter for estimating the second precipitation attenuation from the single polarization data using the first precipitation attenuation; The second precipitation attenuation is estimated from the single polarization data using the calculation parameters.

[0090] (7) An information processing device according to any one of (1) to (6), The processing unit obtains the calculation parameter from the single polarization data using a machine learning model in which a relationship between the first precipitation attenuation and the calculation parameter has been learned.

[0091] (8) An information processing device according to any one of (1) to (7), The processing unit calculates an estimate of the second precipitation intensity from the first precipitation intensity, calculates an integral value of the second precipitation attenuation from the difference between the estimate and the single polarization data, and calculates the second precipitation attenuation from the integral value and the single polarization data.

[0092] (9) An information processing device according to any one of (1) to (8), The processing unit calculates the second precipitation attenuation using a machine learning model in which a relationship between the first precipitation intensity and the second precipitation attenuation has been learned.

[0093] (10) An information processing device according to any one of (1) to (9), The processing unit estimates the second precipitation attenuation from the first precipitation intensity and the single polarization data.

[0094] (11) An information processing method for processing data from a single-polarized radar and a dual-polarized radar located at different positions, comprising the steps of: acquiring dual-polarized data from the dual-polarized radar; Acquiring single-polarized data from the single-polarized radar; estimating a first precipitation rate from the dual polarization data; estimating a first precipitation attenuation from the dual polarization data; estimating a second precipitation attenuation from the single polarization data; correcting the single polarization data using the first precipitation attenuation or the second precipitation attenuation; estimating a second precipitation rate from the corrected single polarization data; an information processing method, comprising: synthesizing the first precipitation rate and the second precipitation rate using a spatial resolution of the first precipitation rate and a spatial resolution of the second precipitation rate.

[0095] (12) A program for processing data from a single-polarized radar and a dual-polarized radar located at different positions, comprising: acquiring dual-polarized data from the dual-polarized radar; acquiring single-polarized data from the single-polarized radar; estimating a first precipitation rate from the dual polarization data; estimating a first precipitation attenuation from the dual polarized data; estimating a second precipitation attenuation from the single polarization data; correcting the single polarization data using the first precipitation attenuation or the second precipitation attenuation; estimating a second precipitation rate from the corrected single polarization data; A program that synthesizes the first precipitation rate and the second precipitation rate using a spatial resolution of the first precipitation rate and a spatial resolution of the second precipitation rate.

[0096] (13) A single-polarized radar; A dual polarized radar located at a position different from the single polarized radar; An information processing device, The information processing device includes: A first acquisition unit that acquires dual polarization data from the dual polarization radar; A second acquisition unit that acquires single polarized data from the single polarized radar; a processing unit for processing the dual polarization data and the single polarization data, The processing unit includes: estimating a first precipitation rate from the dual polarization data; estimating a first precipitation attenuation from the dual polarization data; estimating a second precipitation attenuation from the single polarization data; correcting the single polarization data using the first precipitation attenuation or the second precipitation attenuation; estimating a second precipitation rate from the corrected single polarization data; a radar system that combines the first precipitation rate and the second precipitation rate using a spatial resolution of the first precipitation rate and a spatial resolution of the second precipitation rate.

[0097] The present invention is not limited to the above-described embodiment, and the components can be modified and embodied in the implementation stage without departing from the gist of the invention. In addition, various inventions can be formed by appropriately combining the multiple components disclosed in the above-described embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, components from different embodiments may be appropriately combined. [Explanation of symbols]

[0098] 6... dual polarized radar, 8... single polarized radar, 10... information processing device, 12, 14... acquisition unit, 16... processing unit, 18... output unit, 32... coordinate conversion unit, 34, 52... precipitation intensity estimation unit, 36, 42... attenuation estimation unit, 44... priority information generation unit, 48... attenuation correction unit, 56... synthesis unit

Claims

1. An information processing device that processes data from a single polarization radar and a dual polarization radar that are located at different positions, A first acquisition unit that acquires dual polarization data from the dual polarization radar; A second acquisition unit that acquires single polarized data from the single polarized radar; a processing unit for processing the dual polarization data and the single polarization data, The processing unit includes: estimating a first precipitation rate from the dual polarization data; estimating a first precipitation attenuation from the dual polarized data; estimating a second precipitation attenuation from the single polarization data; correcting the single polarization data using the first precipitation attenuation or the second precipitation attenuation; estimating a second precipitation rate from the corrected single polarization data; an information processing device that combines the first precipitation intensity and the second precipitation intensity using a spatial resolution of the first precipitation intensity and a spatial resolution of the second precipitation intensity.

2. The information processing device according to claim 1 , wherein the processing unit converts coordinates of at least one of the dual polarization data or the single polarization data so that coordinates of the single polarization data indicating a first location correspond to coordinates of the dual polarization data.

3. The information processing apparatus according to claim 1 , wherein the processing unit combines the first precipitation intensity and the second precipitation intensity further using the position of the single polarization radar and the position of the dual polarization radar.

4. The processing unit determines a spatial resolution W １ and the spatial resolution W of the second precipitation rate ２ Using the first precipitation intensity R １ and the second precipitation intensity R ２ The combined precipitation intensity R is calculated as １ R ２ +W ２ R １ ) / (W １ +W ２ 2. The information processing apparatus according to claim 1, further comprising:

5. The processing unit includes: correcting the second precipitation intensity using a ratio between the first precipitation intensity and the second precipitation intensity; The information processing apparatus according to claim 1 , wherein the first precipitation intensity and the corrected second precipitation intensity are combined.

6. The processing unit includes: determining a calculation parameter for estimating the second precipitation attenuation from the single polarization data using the first precipitation attenuation; The information processing apparatus according to claim 1 , wherein the second precipitation attenuation is estimated from the single polarization data by using the calculation parameters.

7. The information processing device according to claim 6 , wherein the processing unit determines the calculation parameter from the single polarization data by using a machine learning model in which a relationship between the first precipitation attenuation and the calculation parameter has been learned.

8. The information processing device according to claim 1 , wherein the processing unit calculates an estimate of the second precipitation intensity from the first precipitation intensity, calculates an integral value of the second precipitation attenuation from a difference between the estimate and the single polarization data, and calculates the second precipitation attenuation from the integral value and the single polarization data.

9. The information processing device according to claim 8 , wherein the processing unit determines the second precipitation attenuation using a machine learning model in which a relationship between the first precipitation intensity and the second precipitation attenuation has been learned.

10. The information processing apparatus according to claim 1 , wherein the processing unit estimates the second precipitation attenuation from the first precipitation intensity and the single polarization data.

11. An information processing method for processing data from a single polarization radar and a dual polarization radar that are located at different positions, comprising: acquiring dual-polarized data from the dual-polarized radar; Acquiring single-polarized data from the single-polarized radar; estimating a first precipitation rate from the dual polarization data; estimating a first precipitation attenuation from the dual polarized data; estimating a second precipitation attenuation from the single polarization data; correcting the single polarization data using the first precipitation attenuation or the second precipitation attenuation; estimating a second precipitation rate from the corrected single polarization data; an information processing method, comprising: synthesizing the first precipitation rate and the second precipitation rate using a spatial resolution of the first precipitation rate and a spatial resolution of the second precipitation rate.

12. A program for processing data from a single-polarized radar and a dual-polarized radar located at different positions, acquiring dual-polarized data from the dual-polarized radar; acquiring single-polarized data from the single-polarized radar; estimating a first precipitation rate from the dual polarization data; estimating a first precipitation attenuation from the dual polarized data; estimating a second precipitation attenuation from the single polarization data; correcting the single polarization data using the first precipitation attenuation or the second precipitation attenuation; estimating a second precipitation rate from the corrected single polarization data; A program that synthesizes the first precipitation rate and the second precipitation rate using a spatial resolution of the first precipitation rate and a spatial resolution of the second precipitation rate.

13. A single polarized radar; A dual polarized radar located at a position different from the single polarized radar; An information processing device, The information processing device includes: A first acquisition unit that acquires dual polarization data from the dual polarization radar; A second acquisition unit that acquires single polarized data from the single polarized radar; a processing unit for processing the dual polarization data and the single polarization data, The processing unit includes: estimating a first precipitation rate from the dual polarization data; estimating a first precipitation attenuation from the dual polarized data; estimating a second precipitation attenuation from the single polarization data; correcting the single polarization data using the first precipitation attenuation or the second precipitation attenuation; estimating a second precipitation rate from the corrected single polarization data; The radar system combines the first precipitation rate and the second precipitation rate using a spatial resolution of the first precipitation rate and a spatial resolution of the second precipitation rate.

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