A method and system for synchronous inversion of Doppler precipitation radar precipitation and three-dimensional wind field

Abstract

The present invention belongs to the field of microwave remote sensing and relates to a method and system for synchronous inversion of Doppler precipitation radar precipitation and three-dimensional wind field. The method includes: a method for synchronous inversion of Doppler precipitation radar precipitation and three-dimensional wind field, comprising: determining the reflectivity factor of the observation area through the echo power of the Doppler precipitation radar; determining the precipitation area and calculating the size of the precipitation particles based on the reflectivity factor; calculating the vertical falling velocity of the precipitation particles based on the precipitation particle size; calculating the radial velocity of the precipitation particles based on the echo phase of the Doppler precipitation radar; removing the vertical falling velocity of the precipitation particles to obtain the radial motion velocity of the precipitation particles caused by the wind field; and inverting the three-dimensional wind field of the precipitation area based on the radial motion velocity of the precipitation particles caused by the wind field, combining the radar observation geometry and the three-dimensional wind field inversion algorithm. The method of the present invention improves the accuracy of wind field inversion.

Description

Technical Field

[0001] The present invention belongs to the field of microwave remote sensing, and in particular relates to a method and system for synchronous inversion of Doppler precipitation radar precipitation and three-dimensional wind field. Background Art

[0002] Measurements of precipitation and atmospheric wind fields are of great significance in meteorology and weather forecasting. Precipitation is a key component of Earth's water cycle and is crucial for water resource management, agricultural production, and the maintenance of ecosystems. Atmospheric wind fields, as a key driving factor in weather systems, not only control the generation and transport of precipitation but are also closely linked to the evolution of weather systems such as cyclones and anticyclones. Precise measurements of precipitation and wind fields can reveal the mechanisms of their interaction, providing reliable data support for weather forecasting, climate change research, and disaster prevention and mitigation.

[0003] Currently, precipitation measurement technology has made significant progress, covering a variety of observation methods such as ground, air and satellite. Weather radar can achieve real-time monitoring over a large area by inverting the intensity and structure of precipitation through the spatial distribution of radar reflectivity factors. Satellite observations provide important support for global precipitation measurements, especially in areas such as oceans and mountainous areas where it is difficult to deploy ground instruments. Satellites based on microwave and infrared sensors (such as TRMM and GPM) can capture the spatial distribution and intensity of precipitation, and have the characteristics of wide coverage and high temporal resolution. However, precipitation radar cannot measure the speed of the target and cannot obtain speed information.

[0004] Currently, atmospheric wind detection methods primarily include spaceborne infrared "cloud-guided wind" technology, ground-based wind profiler radars, and spaceborne laser wind radars. Due to limited penetration, spaceborne infrared "cloud-guided wind" technology cannot obtain vertical distribution information of atmospheric winds within clouds. Ground-based wind profiler radars, constrained by natural conditions such as topography, are difficult to deploy over oceans and remote land areas, hindering global network observations. Spaceborne laser wind radars, such as the Aladdin radar carried by the Aeolus satellite, can accurately detect atmospheric winds in clear-sky areas. However, because lasers cannot penetrate clouds, the Aeolus satellites are unable to obtain wind data within clouds. The global average cloud coverage exceeds 66%, and cloud coverage in coastal areas can reach 80% to 90%, resulting in a significant loss of critical wind data. Conical scanning Doppler radars are capable of detecting three-dimensional wind fields within clouds. However, the accuracy of 3D wind field calculations depends on the quality of the target particle radial velocity data. If the radial velocity data contains a large amount of information about areas without meteorological targets, the inversion accuracy will be reduced. Therefore, it is necessary to use radar reflectivity factor measurements to determine precipitation areas and filter the radial velocity in these areas. In addition, for Doppler precipitation radars, the measured radial velocity includes the vertical falling velocity of particles caused by gravity. Therefore, this effect must be removed during the inversion process to accurately estimate the 3D wind field. Summary of the Invention

[0005] The purpose of the present invention is to overcome the defects of the prior art and propose a method and system for synchronous inversion of Doppler precipitation radar precipitation and three-dimensional wind field.

[0006] In view of this, the present invention proposes a method for synchronous inversion of Doppler precipitation radar precipitation and three-dimensional wind field, comprising:

[0007] Step 1) determining the reflectivity factor of the observation area through the echo power of the Doppler precipitation radar;

[0008] Step 2) Determine the precipitation area and calculate the precipitation particle size based on the reflectivity factor;

[0009] Step 3) calculating the vertical falling velocity of the precipitation particles based on the size of the precipitation particles;

[0010] Step 4) Calculating the radial velocity of the precipitation particles based on the echo phase of the Doppler precipitation radar; removing the vertical falling velocity of the precipitation particles to obtain the radial motion velocity of the precipitation particles caused by the wind field;

[0011] Step 5) Based on the radial motion velocity of precipitation particles caused by the wind field, combined with the radar observation geometry and the three-dimensional wind field inversion algorithm, the three-dimensional wind field of the precipitation area is inverted.

[0012] Preferably, the Doppler precipitation radar is a satellite-borne or airborne radar, which adopts a multiple pulse repetition frequency working mode to expand the measurable radial velocity range, and adopts a conical scanning system.

[0013] Preferably, the reflectivity factor Z of the observation area in step 1) is m for:

[0014]

[0015] Where r is the distance between the observation area and the radar, λ is the wavelength of the electromagnetic wave, |K| is the dielectric constant, G at is the transmitting antenna gain, G ar is the receiving antenna gain, θ 0a is the cross-track beamwidth, θ 0c is the beam width along the track, c is the speed of light, τ is the transmit pulse width, P t is the transmission power, P r is the received power.

[0016] Preferably, the step 2) comprises:

[0017] According to the reflectivity factor Z of the observation area m , the precipitation intensity I is determined by the empirical relationship between radar reflectivity factor and precipitation intensity:

[0018] Z m =200I 1.6

[0019] According to the precipitation intensity I, the attenuation parameter Λ is determined as:

[0020] Λ=4.11I -0.21

[0021] The distribution N(D) describing the raindrop particle diameter D is determined by the attenuation parameter Λ and the normalized number concentration constant N0:

[0022] N(D)=N0e -ΛD

[0023] Determine the average particle size D by numerical integration mean for:

[0024]

[0025] Preferably, the calculation process of the echo phase of the Doppler precipitation radar in step 4) includes:

[0026] For the signal transmitted by the Doppler radar, the baseband echo s(t) obtained after down-conversion by the receiver is:

[0027] s(t)=exp(-j2π[f c τ-0.5α(t-τ) 2 ])

[0028] α=W / T p

[0029] Among them, f c is the carrier frequency, t is the echo time within the pulse, τ is the echo time shift, α is the frequency modulation slope, T p is the pulse width, W is the signal bandwidth; j represents the imaginary part;

[0030] Construct the reference function s of matched filtering ref (t) is:

[0031] s ref (t)=exp(-j2π[f c τ0-0.5α(t-τ0) 2 ])

[0032] Where τ0 is the reference signal time shift;

[0033] The pulse compression signal s is obtained by Fourier transform out for:

[0034] s out=IFFT{FFT[s(t)]·conj[FFT[s ref (t)]]}

[0035] Among them, FFT is Fourier transform, IFFT is inverse Fourier transform, and conj means finding the conjugate of the complex number;

[0036] Take two adjacent pulse compression signals A=s out1 , B=s out2 , N is the number of related points, then the correlation coefficient ρ(A, B) of adjacent pulse compression signals is:

[0037]

[0038] Among them, μ A , μ B and σ A , σ B , are the mean and standard deviation of A and B respectively;

[0039] Take the phase of ρ(A,B) This is the echo phase.

[0040] Preferably, in step 4), the radial velocity V of the precipitation particles is target The calculation process includes:

[0041] According to the phase of the two pulse repetition frequencies The corresponding radial velocities after folding are: Among them, V u1 , V u2 are the maximum unambiguous velocity under the corresponding pulse repetition interval, V1+MV u1 =V2+MV u2 =V, M is the number of folds, V is the true speed, let Then the true velocity V after unfolding is:

[0042]

[0043] in, is the maximum unambiguous speed after expansion:

[0044] For the maximum unambiguous velocity after double PRF expansion calculated at each observation attitude, n1 and n2 that make the equation valid are calculated according to the following formula:

[0045]

[0046]

[0047] According to n1 and n2, calculate the radial velocity V after unfolding corresponding to each single pulse repetition interval. 1True , V 2True :

[0048] V 1True =V1+2n1V u1

[0049] V 2True =V2+2n2V u2

[0050] The radial velocity V is calculated according to the following formula True :

[0051]

[0052] The projection V of the moving platform where the radar is located in the observation direction is obtained according to the following formula: platform_proj :

[0053] V platform_proj =V platform ·V observe

[0054] Among them, V platform It represents the platform motion in the geographic coordinate system and consists of the speeds in three directions:

[0055] V platform =(V north ,V east ,V up )

[0056] Among them, V north is the northward velocity of the platform, V east is the platform's eastward velocity, V up is the upward speed of the platform;

[0057] V observe is the radar observation vector:

[0058]

[0059] in, is the angle between the radar observation direction and the positive direction of the z-axis; θ is the angle between the projection of the radar observation direction on the xy plane and the positive direction of the x-axis;

[0060] The radial velocity V of precipitation particles can be obtained according to the following formula: target :

[0061] V target =V Ture -V platform_proj .

[0062] Preferably, the radial motion velocity V of the precipitation particles caused by the wind field in step 4) is wind for:

[0063]

[0064] Preferably, the three-dimensional wind field in the precipitation area in step 5) is:

[0065]

[0066] Among them, V x , V y , V z are the velocities of the atmospheric three-dimensional wind field in the x, y, and z directions respectively, p′ represents the transposed matrix of the observation matrix p,

[0067]

[0068] in, and θ n are the elevation and azimuth angles corresponding to the nth observation of the target area, n>3.

[0069] In another aspect, the present invention provides a Doppler precipitation radar precipitation and three-dimensional wind field synchronous inversion system, comprising:

[0070] The reflectivity factor calculation module is used to determine the reflectivity factor of the observation area through the echo power of the Doppler precipitation radar;

[0071] The precipitation particle size calculation module is used to determine the precipitation area and calculate the precipitation particle size based on the reflectivity factor;

[0072] A vertical falling velocity calculation module is used to calculate the vertical falling velocity of precipitation particles according to the size of precipitation particles;

[0073] The radial motion velocity calculation module is used to calculate the radial velocity of precipitation particles based on the echo phase of the Doppler precipitation radar; the vertical falling velocity of precipitation particles is removed to obtain the radial motion velocity of precipitation particles caused by the wind field;

[0074] The inversion module is used to invert the three-dimensional wind field in the precipitation area based on the radial motion speed of precipitation particles caused by the wind field, combined with radar observation geometry and three-dimensional wind field inversion algorithm.

[0075] Compared with the prior art, the advantages of the present invention are:

[0076] This invention provides a method for synchronously inverting Doppler radar precipitation and three-dimensional wind fields. This method uses radar reflectivity factor measurements to determine the precipitation area and screen radial velocity measurements within the precipitation area to improve wind field inversion accuracy. Furthermore, the reflectivity factor is used to obtain precipitation particle size information, thereby determining the vertical drop velocity of the particles. By subtracting the particle drop velocity from the calculated radial velocity, the wind-induced radial velocity is obtained, further improving the accuracy of vertical wind velocity inversion. BRIEF DESCRIPTION OF THE DRAWINGS

[0077] Figure 1 The present invention is a flow chart of the method for synchronous inversion of Doppler precipitation radar precipitation and three-dimensional wind field. DETAILED DESCRIPTION

[0078] The purpose of the embodiments of the present invention is to provide a method for synchronously inverting Doppler precipitation radar precipitation and three-dimensional wind fields. The method uses the precipitation radar's echo power to determine the reflectivity factor of the observation area; uses the radar reflectivity factor to determine the precipitation area and calculate the precipitation particle size; calculates the vertical drop velocity of the precipitation particles based on the precipitation particle size; and calculates the radial velocity of the precipitation particles based on the precipitation radar's echo phase. The vertical drop velocity of the precipitation particles is removed to obtain the radial velocity of the precipitation particles caused by the wind field. Based on the radial velocity of the precipitation particles caused by the wind field, the three-dimensional wind field of the precipitation area is inverted using the radar observation geometry and a three-dimensional wind field inversion algorithm.

[0079] The method specifically includes:

[0080] Step 1) Determine the reflectivity factor of the observation area through the echo power of the precipitation radar.

[0081] Doppler precipitation radar is a spaceborne / airborne radar that uses a multiple pulse repetition frequency (PRF) operating mode to expand the measurable radial velocity range and adopts a conical scanning system.

[0082] Step 2): According to the radar reflectivity factor obtained in step 1), the precipitation area is determined and the size of the precipitation particles is calculated.

[0083] Step 2) further comprises:

[0084] The precipitation intensity I is determined by the empirical relationship between radar reflectivity factor and precipitation intensity:

[0085] z m =200I 1.6

[0086] The attenuation parameter Λ is determined by the precipitation intensity I:

[0087] Λ=4.11I -0.21

[0088] By using the decay parameter Λ, the normalized number concentration constant N0 (8000m -3 mm -1 ) Determine the distribution N(D) that describes the diameter D of raindrop particles:

[0089] N(D)=N0e -ΛD

[0090] Determine the average particle size D by numerical integration mean :

[0091]

[0092] Step 3) Calculate the vertical falling velocity of the precipitation particles using the precipitation particle size obtained in step 2).

[0093] Step 3) further comprises:

[0094] The interference phase of the target is calculated using the pulse pair interferometry method, and the radial velocity of the target is calculated using the dual pulse repetition frequency algorithm. The radial motion velocity of the precipitation particles caused by the wind field is obtained by subtracting the terminal falling velocity of the particles from the calculated radial velocity.

[0095] Step 4) Calculate the radial velocity of the precipitation particles based on the echo phase of the precipitation radar; remove the vertical falling velocity of the precipitation particles obtained in step 3) to obtain the radial motion velocity of the precipitation particles caused by the wind field;

[0096] Step 5) Based on the radial motion velocity of precipitation particles caused by the wind field obtained in step 4), the three-dimensional wind field of the precipitation area is inverted by combining radar observation geometry and a three-dimensional wind field inversion algorithm.

[0097] The technical solution of the present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0098] Example 1

[0099] Embodiment 1 of the present invention provides a method for synchronously inverting Doppler precipitation radar precipitation and three-dimensional wind fields. The method uses the echo power of the precipitation radar to determine the reflectivity factor of the observation area; uses the radar reflectivity factor to determine the precipitation area and calculate the precipitation particle size; calculates the vertical drop velocity of the precipitation particles based on the precipitation particle size; calculates the radial velocity of the precipitation particles based on the echo phase of the precipitation radar; removes the vertical drop velocity of the precipitation particles to obtain the radial motion velocity of the precipitation particles caused by the wind field; and uses the radial motion velocity of the precipitation particles caused by the wind field to invert the three-dimensional wind field of the precipitation area, combining the radar observation geometry and a three-dimensional wind field inversion algorithm.

[0100] The method specifically includes:

[0101] Step 1) Determine the reflectivity factor of the observation area based on the echo power P of the precipitation radar. r , the radar reflectivity factor Z is calculated by the following formula m :

[0102]

[0103] Where r is the distance between the target and the radar, λ is the wavelength of the electromagnetic wave, |K| is the dielectric constant, G at is the transmitting antenna gain, G ar is the receiving antenna gain, θ 0a is the cross-track beamwidth, θ 0c is the beam width along the track, c is the speed of light, τ is the transmit pulse width, P t is the transmission power, P r is the received power.

[0104] Step 2) Determine the precipitation area and calculate the precipitation particle size based on the radar reflectivity factor obtained in step 1).

[0105] Take the logarithm of the radar reflectivity factor obtained in step 1) to obtain dBZ:

[0106] dBZ=10log 10 (Z m )

[0107] Among all the observation data, data with dBZ values ​​greater than 10dB were screened and identified as precipitation areas.

[0108] When the dBZ value range is within 10-40dB, the precipitation intensity I (unit: mm / h) is determined according to the following formula:

[0109] Z m =200I 1.6

[0110] When the dBZ value is greater than 40dB, the precipitation intensity I is determined according to the following formula

[0111] Z m =486I 1.37

[0112] The attenuation parameter Λ is determined by the precipitation intensity I:

[0113] Λ=4.11I -0.21

[0114] By using the decay parameter Λ and the normalized number concentration constant N0 (8000m -3 mm -1 ), determine the distribution N(D) of raindrop particle diameter D:

[0115] N(d)=N0e -ΛD

[0116] Determine the average particle diameter D by numerical integration mean (Unit: mm):

[0117]

[0118] Step 3) Calculate the vertical falling velocity of the precipitation particles using the precipitation particle size obtained in step 2).

[0119] For precipitation scenes, when the dBZ value is greater than 10dB, according to the average particle diameter D mean , the vertical falling velocity v(D) of the particle can be determined.

[0120] Step 4) calculating the echo phase from the original echo signal of the precipitation radar;

[0121] The signal transmitted by the radar is a linear frequency modulated pulse signal, as shown in the following formula:

[0122] s(t)=exp(j2π[f c t+0.5αt 2 ]), 0≤t≤T p ,α=W / T p

[0123] Among them, f c is the carrier frequency, α is the frequency modulation slope, T p is the pulse width, W is the signal bandwidth, t is the echo time within the pulse, and τ is the echo time shift.

[0124] The radar echo from a point target at R (time delay τ = 2R / c) can be expressed as:

[0125] s(t)=exp(j2π[f c (t-τ)+0.5α(t-τ) 2 ])

[0126] The baseband echo obtained after down-conversion by the receiver can be expressed as:

[0127] s(t)=exp(-j2π[f c τ-0.5α(t-τ) 2 ])

[0128] The reference function of the matched filter constructed according to the transmission signal bandwidth, duration, and sampling rate can be expressed as:

[0129] s ref (t)=exp(-j2π[f c τ0-0.5α(t-τ0)2 ])

[0130] Where τ0 is the reference signal time shift.

[0131] The pulse compression signal s is obtained by Fourier transform out , which can be expressed as:

[0132] s out =IFFT{FFT[s(t)]·conj[FFT[s ref (t)]]}

[0133] Take two adjacent pulse compression signals A=s out1 , B=s out2 , N is the number of related points, then the correlation coefficient of adjacent pulse compression signals is:

[0134]

[0135] where μ A , μ B and σ A , σ B , are the mean and standard deviation of A and B respectively. ρ(A,B) is a complex number, its phase This is the interference phase.

[0136] Step 5) Calculating the radial velocity of the precipitation particles from the echo phase;

[0137] For the same target velocity, different pulse repetition intervals will result in different phase values. The expanded radial velocity can be calculated using the different phase values ​​under the two pulse repetition frequencies.

[0138] For the radial velocity after folding, the phases at the two pulse repetition frequencies are: The corresponding radial velocities after folding are: Among them, V u1 , V u2 are the maximum unambiguous speeds under the corresponding pulse repetition intervals. And V1+MV u1 =V2+MV u2 =V, M is the number of folds, V is the true speed. The true speed after unfolding can be calculated as follows:

[0139]

[0140] in is the maximum unambiguous speed after expansion:

[0141] For each observation attitude, the maximum unambiguous velocity after double PRF expansion is calculated, and the n1 and n2 that make the equation valid are calculated using the following formula:

[0142]

[0143] Using the calculated n1n2, calculate the unfolded radial velocity V corresponding to each single pulse repetition interval 1True , V 2True :

[0144]

[0145] Then the radial velocity after unfolding corresponding to each single pulse repetition interval is averaged, and the calculated radial velocity V True :

[0146]

[0147] Since the radar is located on a mobile platform, the calculated radial velocity is affected by both the target motion and the platform motion. Therefore, after the radial velocity is calculated, the influence of the platform motion needs to be excluded. The platform motion V platform In the geographic coordinate system, the positive direction of the x-axis points to the geographic north, the positive direction of the y-axis points to the geographic east, and the positive direction of the z-axis is perpendicular to the plane where the x-axis and y-axis are located and points to the sky. platform It consists of three directions of speed: V north : Northward velocity of platform movement, V east Platform eastward speed, V up : Platform upward speed:

[0148] V platform =(V north ,V east ,V up )

[0149] The platform motion affects the velocity measurement in the observation direction. The radar observation vector V observe for:

[0150]

[0151] in is the pitch angle observed from the satellite / aircraft, which is the angle between the radar observation direction and the positive direction of the z-axis; θ is the azimuth angle, which is the angle between the projection of the radar observation direction on the xy plane and the positive direction of the x-axis.

[0152] Then the projection of the platform motion velocity in the observation direction is V platform_proj Calculated by the following formula:

[0153] V platform_proj=V platform ·V observe

[0154] Radial velocity of precipitation particles V target is the calculated radial velocity V True Subtract the projection V of the platform motion velocity in the observation direction platform :

[0155] V target =V True -V platform_proj

[0156] Step 6) removing the vertical falling velocity of the precipitation particles obtained in step 3) to obtain the radial motion velocity of the precipitation particles caused by wind;

[0157] The target radial velocity V target Subtract the radial projection of the vertical velocity of precipitation v(D) obtained in step 3) to obtain the radial wind speed V wind , which can be expressed as

[0158]

[0159] Step 7) Based on the radial motion velocity of precipitation particles caused by the wind field obtained in step 6), combined with radar observation geometry and a three-dimensional wind field inversion algorithm, the three-dimensional wind field of the precipitation area is inverted to obtain.

[0160] After obtaining the radial motion velocity of precipitation particles caused by the wind field, the wind speed and direction in the target area are calculated by the least squares method based on more than three independent observations of the target area.

[0161] Assume that the pitch angle and azimuth angle corresponding to the i-th observation of the target area (i is greater than or equal to 3) are expressed as and θ i , i represents the i-th observation, there are n observations in total, then the observation matrix is ​​expressed by the following formula:

[0162]

[0163] The three-dimensional atmospheric wind field is calculated according to the following formula:

[0164]

[0165] Among them, V x , V y , V z are the velocities of the three-dimensional atmospheric wind field in the x, y, and z directions, respectively. The definitions of the three directions have been given in step 5). V wind is the radial wind speed calculated in step 6), and p′ represents the transposed matrix of p.

[0166] Example 2

[0167] Embodiment 2 of the present invention provides a Doppler precipitation radar precipitation and three-dimensional wind field synchronous inversion system, which is implemented based on the method of embodiment 1. The system includes:

[0168] The reflectivity factor calculation module is used to determine the reflectivity factor of the observation area through the echo power of the Doppler precipitation radar;

[0169] The precipitation particle size calculation module is used to determine the precipitation area and calculate the precipitation particle size based on the reflectivity factor;

[0170] A vertical falling velocity calculation module is used to calculate the vertical falling velocity of precipitation particles according to the size of precipitation particles;

[0171] The radial motion velocity calculation module is used to calculate the radial velocity of precipitation particles based on the echo phase of the Doppler precipitation radar; the vertical falling velocity of precipitation particles is removed to obtain the radial motion velocity of precipitation particles caused by the wind field;

[0172] The inversion module is used to invert the three-dimensional wind field in the precipitation area based on the radial motion speed of precipitation particles caused by the wind field, combined with radar observation geometry and three-dimensional wind field inversion algorithm.

[0173] Finally, it should be noted that the above embodiments are intended only to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions to the technical solutions of the present invention do not depart from the spirit and scope of the technical solutions of the present invention and are intended to be encompassed by the claims of the present invention.

Claims

1. A method for synchronous inversion of Doppler precipitation radar precipitation and three-dimensional wind field, comprising: Step 1) determining the reflectivity factor of the observation area through the echo power of the Doppler precipitation radar; Step 2) Determine the precipitation area and calculate the precipitation particle size based on the reflectivity factor; Step 3) calculating the vertical falling velocity of the precipitation particles based on the size of the precipitation particles; Step 4) Calculating the radial velocity of the precipitation particles based on the echo phase of the Doppler precipitation radar; removing the vertical falling velocity of the precipitation particles to obtain the radial motion velocity of the precipitation particles caused by the wind field; Step 5) Based on the radial motion velocity of precipitation particles caused by the wind field, combined with the radar observation geometry and the three-dimensional wind field inversion algorithm, the three-dimensional wind field of the precipitation area is inverted.

2. The method for synchronous inversion of Doppler precipitation radar precipitation and three-dimensional wind field according to claim 1, characterized in that: The Doppler precipitation radar is a satellite-borne or airborne radar, which adopts a multiple pulse repetition frequency working mode to expand the measurable radial velocity range and adopts a conical scanning system.

3. The method for synchronous inversion of Doppler precipitation radar precipitation and three-dimensional wind field according to claim 1, characterized in that: The step 1) observing the reflectivity factor Z of the area m for: Where r is the distance between the observation area and the radar, λ is the wavelength of the electromagnetic wave, |K| is the dielectric constant, G at is the transmitting antenna gain, G ar is the receiving antenna gain, θ 0a is the cross-track beamwidth, θ 0c is the beam width along the track, c is the speed of light, τ is the transmit pulse width, P t is the transmission power, P r is the received power.

4. The method for synchronous inversion of Doppler precipitation radar precipitation and three-dimensional wind field according to claim 3, characterized in that: The step 2) comprises: According to the reflectivity factor Z of the observation area m , the precipitation intensity I is determined by the empirical relationship between radar reflectivity factor and precipitation intensity: FROM m =200I 1.6 According to the precipitation intensity I, the attenuation parameter Λ is determined as: L=4.11I -0.21 The distribution N(D) describing the raindrop particle diameter D is determined by the attenuation parameter Λ and the normalized number concentration constant N0: N(D)=N0e -ΛD Determine the average particle size D by numerical integration mean for:

5. The method for synchronous inversion of Doppler precipitation radar precipitation and three-dimensional wind field according to claim 4, characterized in that: The calculation process of the echo phase of the Doppler precipitation radar in step 4) includes: For the signal transmitted by the Doppler radar, the baseband echo s(t) obtained after down-conversion by the receiver is: s(t)=exp(-j2π[f c τ-0.5α(t-τ) 2 ]) α=W / T p Among them, f c is the carrier frequency, t is the echo time within the pulse, τ is the echo time shift, α is the frequency modulation slope, T p is the pulse width, W is the signal bandwidth; j represents the imaginary part; Construct the reference function s of matched filtering ref (t) is: s ref (t)=exp(-j2π[f c τ0-0.5α(t-τ0) 2 ]) Where τ0 is the reference signal time shift; The pulse compression signal s is obtained by Fourier transform out for: s out =IFFT{FFT[s(t)]·conj[FFT[s ref (t)]]} Among them, FFT is Fourier transform, IFFT is inverse Fourier transform, and conj means finding the conjugate of the complex number; Take two adjacent pulse compression signals A=s out1 , B=s out2 , N is the number of related points, then the correlation coefficient ρ(A, B) of adjacent pulse compression signals is: Among them, μ A , μ B and σ A ,σ B , are the mean and standard deviation of A and B respectively; Take the phase of ρ(A,B) This is the echo phase.

6. The method for synchronous inversion of Doppler precipitation radar precipitation and three-dimensional wind field according to claim 5, characterized in that: In step 4), the radial velocity V of the precipitation particles target The calculation process includes: According to the phase of the two pulse repetition frequencies The corresponding radial velocities after folding are: Among them, V u1 , V u2 are the maximum unambiguous velocity under the corresponding pulse repetition interval, V1+MV u1 =V2+MV u2 =V, M is the number of folds, V is the true speed, let Then the true velocity V after unfolding is: in, is the maximum unambiguous speed after expansion: For the maximum unambiguous velocity after double PRF expansion calculated at each observation attitude, n1 and n2 that make the equation valid are calculated according to the following formula: According to n1 and n2, calculate the radial velocity V after unfolding corresponding to each single pulse repetition interval. 1True , V 2True : In 1True =V1+2n1V u1 <h2 style=";text-align:left;direction:ltr">V<h2 style=";text-align:left;direction:ltr"> 2True <h2 style=";text-align:left;direction:ltr"> =V2+2n2V<h2 style=";text-align:left;direction:ltr"> u2 The radial velocity V is calculated according to the following formula True : The projection V of the moving platform where the radar is located in the observation direction is obtained according to the following formula: platform_proj : V platform_proj =V platform ·V observe Among them, V platform It represents the platform motion in the geographic coordinate system and consists of the speeds in three directions: V platform =(V north ,V east ,V up ) Among them, V north is the northward velocity of the platform, V east is the platform's eastward velocity, V up is the upward speed of the platform; V observe is the radar observation vector: in, is the angle between the radar observation direction and the positive direction of the z-axis; θ is the angle between the projection of the radar observation direction on the xy plane and the positive direction of the x-axis; The radial velocity V of precipitation particles can be obtained according to the following formula: target : V target =V True -V platform_proj 。 7. The method for synchronous inversion of Doppler precipitation radar precipitation and three-dimensional wind field according to claim 6, characterized in that: The radial motion velocity V of precipitation particles caused by the wind field in step 4) wind for: Where v(D) is the vertical falling velocity of precipitation particles.

8. The method for synchronous inversion of Doppler precipitation radar precipitation and three-dimensional wind field according to claim 7, characterized in that: The three-dimensional wind field in the precipitation area in step 5) is: Among them, V x , V y , V z are the velocities of the atmospheric three-dimensional wind field in the x, y, and z directions respectively, p′ represents the transposed matrix of the observation matrix p, in, and θ n are the elevation and azimuth angles corresponding to the nth observation of the target area, n>3.

9. A Doppler precipitation radar precipitation and three-dimensional wind field synchronous inversion system, characterized in that: include: The reflectivity factor calculation module is used to determine the reflectivity factor of the observation area through the echo power of the Doppler precipitation radar; The precipitation particle size calculation module is used to determine the precipitation area and calculate the precipitation particle size based on the reflectivity factor; A vertical falling velocity calculation module is used to calculate the vertical falling velocity of precipitation particles according to the size of precipitation particles; The radial motion velocity calculation module is used to calculate the radial velocity of precipitation particles based on the echo phase of the Doppler precipitation radar; the vertical falling velocity of precipitation particles is removed to obtain the radial motion velocity of precipitation particles caused by the wind field; and The inversion module is used to invert the three-dimensional wind field in the precipitation area based on the radial motion speed of precipitation particles caused by the wind field, combined with radar observation geometry and three-dimensional wind field inversion algorithm.

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