An ionospheric scintillation effect error modeling method, system, device and medium based on a multi-phase screen model

Abstract

A method, system, device and medium for error modeling of ionospheric scintillation effects based on a multi-phase screen model. The method includes: generating a phase screen; obtaining azimuth spectrum data; obtaining an echo signal at the phase screen height; adding the ionospheric scintillation phase at the h i height; azimuth signal compression; inverse Fourier transform; The system, device and medium are used to implement a method for error modeling of ionospheric scintillation effects based on a multi-phase screen model. The present invention uses a multi-phase screen model to simulate ionospheric electron density irregularities, obtains the required echo through decompression processing and phase replacement, and adds the scintillation phases at different heights to the radar echo by multiplying corresponding spatial positions, which can achieve accurate error modeling of ionospheric scintillation effects for spaceborne synthetic aperture radar under distributed targets. The present invention realizes error modeling and simulation of point targets and the entire image affected by ionospheric scintillation effects, and has the advantages of wide bandwidth and strong scalability.

Description

Technical Field

[0001] The present invention relates to the technical field of signal processing, and particularly relates to a method, system, device and medium for modeling the error of ionospheric scintillation effect based on a multi-phase screen model. Background Art

[0002] Spaceborne synthetic aperture radar (SAR) has been widely used in military and people's lives. Since the radar operates above the ionosphere, when imaging the ground, the echo signal will inevitably be affected by the ionosphere, resulting in a decrease in imaging quality. Among them, due to the existence of the irregular structure of the ionospheric electron density, the signal passing through the ionosphere undergoes rapid changes in amplitude and phase, and this effect is called ionospheric scintillation. Ionospheric scintillation will cause the azimuth signal of SAR to defocus, resulting in a decrease in image quality. Therefore, the modeling research on the error of spaceborne SAR affected by ionospheric scintillation effect is particularly important.

[0003] Currently, the error modeling methods for ionospheric scintillation effect at home and abroad mainly use the power-law spectrum to describe the irregular structure of ionospheric electron density, and use the thin phase screen theory to explain and simulate the scintillation effect error caused by the irregular structure of ionospheric electron density. The thin phase screen theory only considers the case when the irregularities are distributed in a single layer, and does not consider the characteristics that the irregularities are distributed in different altitude layers of the ionosphere, so it is impossible to accurately model the ionospheric scintillation effect error.

[0004] To solve this problem, domestic and foreign scholars have proposed to use the multi-phase screen and parabolic equation approximation method to simulate the ionospheric scintillation effect, named "Method for generating multi-phase screen of two-dimensional distribution of ionospheric scintillation phase of GEO SAR", and the patent application with the application number [CN201310519652.1] provides a method for generating multi-phase screen of two-dimensional distribution of ionospheric scintillation phase of GEO SAR. The irregularities of ionospheric electron density are assumed to be thin phase screens distributed in multiple altitude layers. Considering the diffraction effect during the propagation of electromagnetic waves, the parabolic equation approximation is used. By continuously solving the propagation of the signal within the phase screen and the propagation of the signal between the phase screens, the simulation of the ionospheric scintillation effect error is realized. However, this method can only simulate the influence of ionospheric scintillation effect on a single independent scatterer each time. When simulating the influence of scintillation on spaceborne SAR imaging, only small-scene approximation can be used, and it is impossible to accurately simulate the influence of ionospheric scintillation on the entire spaceborne SAR image. Summary of the Invention

[0005] In order to overcome the shortcomings of the above-mentioned existing technologies, the purpose of the present invention is to provide a method, system, device and medium for modeling the ionospheric scintillation effect error based on the multi-phase screen model. The multi-phase screen model is used to simulate the irregularities of the ionospheric electron density, and the received echoes of the radar at different phase screen heights are obtained by means of decompression processing and decompression phase replacement. By multiplying the spatial positions correspondingly, the scintillation phases of the phase screens at different heights are added to the radar echoes, so as to achieve accurate modeling of the ionospheric scintillation effect error of the spaceborne synthetic aperture radar (SAR) under distributed targets.

[0006] In order to achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0007] A method for modeling the ionospheric scintillation effect error based on the multi-phase screen model includes the following steps:

[0008] Step 1, generate phase screens: According to the radar system parameters and the ionospheric parameters at heights h 1 、h 2 …h n respectively generate phase screens at heights h 1 、h 2 …h n to obtain the ionospheric scintillation phases at heights h 1 、h 2 …h n

[0009] Step 2, obtain azimuth spectrum data: Perform a fast Fourier transform (FFT) on the azimuth image data S column by column to obtain the azimuth spectrum data S FFT ;

[0010] Step 3, obtain the echo signal at the phase screen height: According to the radar system parameters, calculate the corresponding reference slant range at height h i Calculate the azimuth decompression phase at height h according to this reference slant range i Add this azimuth decompression phase to the azimuth spectrum data obtained in Step 2 to obtain the azimuth echo spectrum at height h Perform an inverse fast Fourier transform (IFFT) on this azimuth echo spectrum at height h i column by column to obtain the azimuth echo signal at height h i to obtain the azimuth echo signal at height h i

[0011] Step 4, add h iIonospheric scintillation phase in altitude: Add the h obtained in step 3 i Echo signal in azimuth at altitude to the h obtained in step 1 i Ionospheric scintillation phase Φ in altitude scint_hi , to obtain h i Azimuth echo signal affected by ionosphere in altitude

[0012] Step 5, azimuth signal compression: Perform fast Fourier transform (FFT) column by column on the h i Azimuth echo signal affected by ionosphere in altitude obtained in step 4 to obtain h i Azimuth echo spectrum affected by ionosphere in altitude Then divide this h i Azimuth echo spectrum affected by ionosphere in altitude by the h calculated in step 3 i Azimuth decompression phase in altitude to obtain h i Azimuth spectrum data affected by ionosphere in altitude Perform a loop on the obtained h i Azimuth spectrum data affected by ionosphere in altitude and repeatedly apply the operations from step 3 to step 5 until all phase screens at the set altitudes are added to the azimuth echo data, to obtain the azimuth spectrum data S affected by the multi-layer phase screen scintillation phase I_FFT_all ;

[0013] Step 6, inverse Fourier transform: Perform fast inverse Fourier transform (IFFT) column by column on the azimuth spectrum data S affected by the multi-layer phase screen scintillation phase obtained in step 6 I_FFT_all to obtain the azimuth image data S affected by the multi-layer phase screen scintillation phase I_s .

[0014] The process of generating the phase screen in step 1 includes:

[0015] Step 1.1, calculate the azimuth sampling parameters of the phase screen:

[0016] h i The phase screen in altitude is expressed as (i = 1, 2... n, n represents the number of phase screens), and the phase screens at different altitudes have the same size, all N a ×1, N arepresents the number of sampling points in the azimuth direction. Different azimuth sampling points correspond to different azimuth positions. The spatial interval between two adjacent azimuth sampling points on the phase screen at all heights is the same, which is d:

[0017]

[0018] In the formula, V ref represents the radar equivalent velocity with the scene center as the reference, and PRF represents the pulse repetition frequency of the radar;

[0019] Step 1.2, calculate the ionospheric scintillation phase:

[0020] According to the radar system parameters and the azimuth sampling parameters of the phase screen obtained in the above Step 1.1, generate phase screens at heights h 1 、h 2 …h n to obtain the ionospheric scintillation phases at heights h 1 、h 2 …h n The ionospheric scintillation phase

[0021] h i The ionospheric scintillation phase Specifically expressed as:

[0022]

[0023] In the formula, represents the value at the (1, 1) position in the ionospheric scintillation phase at height h i , represents the value at the (N i , 1) position in the ionospheric scintillation phase at height h a .

[0024] The process of obtaining azimuth spectrum data in Step 2 includes:

[0025] Step 2.1, perform a fast Fourier transform on the azimuth image data S column by column:

[0026] Let the one-dimensional azimuth image data S of the SAR be:

[0027]

[0028] In the formula, S 11 represents the value at the (1, 1) position in the image data, represents the value at the (N a , 1) position in the image data;

[0029] Perform a fast Fourier transform (FFT) on the one-dimensional azimuth image data S of the SAR column by column to obtain the azimuth spectrum data S FFT It is:

[0030]

[0031] In the formula, represents the value at the (1, 1) position in the azimuth spectrum data, represents the value at the (N a , 1) position, and FFT(·) represents performing a fast Fourier transform on the matrix column by column;

[0032] Step 2.2, set the initial value of the azimuth spectrum data affected by the scintillation phase and the initial value of the loop parameter i:

[0033]

[0034] i = 1 (6)

[0035] The process of obtaining the echo signal at the phase screen height in step 3 includes:

[0036] Step 3.1, calculate the reference slant range corresponding to the height h i according to the radar system parameters

[0037]

[0038] In the formula, R 0 represents the reference slant range of the scene center, h i is the height of the i-th phase screen, and H represents the flight height of the radar when passing through the scene center point;

[0039] Step 3.2, calculate the azimuth frequency f of the azimuth spectrum data at each azimuth position according to the radar system parameters a :

[0040]

[0041] Step 3.3, according to the reference slant range corresponding to the height h i calculated in step 3.1 and the azimuth frequency f at each azimuth position calculated in step 3.2 a , the azimuth decompression phase at the height h i can be calculated :

[0042]

[0043] In the formula, denote the azimuth frequency f a the value at the (1, 1) position in denote the azimuth frequency f a in the a , 1) position;

[0044] Step 3.4, multiply the azimuth decompression phase h i at height by the azimuth spectrum data S obtained in Step 2 FFT to obtain h i the azimuth echo spectrum at height :

[0045]

[0046] where j represents the imaginary unit, i.e., denote h i the azimuth decompression phase at height the value at the (1, 1) position in denote h i the azimuth decompression phase at height in the a , 1) position;

[0047] Step 3.5, perform a fast inverse Fourier transform (IFFT) on the h i azimuth echo spectrum at height column by column to obtain h i the azimuth echo signal at height :

[0048]

[0049] where denote h i the value at the (1, 1) position in the azimuth echo signal at height denote h i the value at the (N a , 1) position in the azimuth echo signal at height, and IFFT(·) represents performing a fast inverse Fourier transform on the matrix column by column.

[0050] In the said Step 4, the process of adding the ionospheric scintillation phase h i at height is as follows:

[0051] Add the h i azimuth echo signal at height obtained in Step 3 to the h obtained in Step 1i Ionospheric scintillation phase in altitude Obtain h i Azimuth echo signal affected by ionosphere in altitude Specifically expressed as:

[0052]

[0053] The process of azimuth signal compression in step 5 includes:

[0054] Step 5.1, Azimuth Fourier transform:

[0055] Perform fast Fourier transform (FFT) on the h i Azimuth echo signal affected by ionosphere in altitude obtained in step 4 column by column to obtain h i Azimuth echo spectrum affected by ionosphere in altitude :

[0056]

[0057] In the formula, represents the value at the (1, 1) position in h i Azimuth echo spectrum affected by ionosphere in altitude ; represents the value at the (N i Azimuth echo spectrum affected by ionosphere in altitude , 1) position; a

[0058] Step 5.2, Azimuth frequency domain compression:

[0059] Divide the h i Azimuth echo spectrum affected by ionosphere in altitude obtained in step 5.1 by the h i Azimuth decompression phase in altitude calculated in step 3 to obtain h i Azimuth spectrum data affected by ionosphere in altitude :

[0060]

[0061] Step 5.3, Execute loop:

[0062] Apply the azimuth spectrum data obtained in step 5.2 repeatedly in steps 3 to 5, and check whether the loop parameter i exceeds the upper limit:

[0063] ​If \(i\geq n\), the azimuth spectrum data \(S\) affected by the scintillation phase of the multi-layer phase screen is obtained. I_FFT_all :

[0064]

[0065] If \(i < n\), update the loop parameter \(i\) and return to step 3:

[0066] \(i = i + 1\) (16)

[0067] The process of the inverse Fourier transform in step 6 is as follows:

[0068] Perform a fast inverse Fourier transform (IFFT) on the azimuth spectrum data \(S\) affected by the scintillation phase of the multi-layer phase screen obtained in step 5 column by column to obtain the one-dimensional azimuth image data \(S\) affected by the scintillation phase of the multi-layer phase screen. I_FFT_all Specifically: I_s :

[0069]

[0070] In the formula, represents the value at the (1, 1) position in the one-dimensional azimuth image data affected by the scintillation phase of the multi-layer phase screen, represents the value at the (N a , 1) position in the one-dimensional azimuth image data affected by the scintillation phase of the multi-layer phase screen.

[0071] An ionospheric scintillation effect error modeling system based on a multi-phase screen model includes:

[0072] A phase screen generation module for generating a phase screen according to the selected ionospheric phase screen height to obtain the ionospheric scintillation phase at the corresponding height.

[0073] An echo signal acquisition module for obtaining the azimuth echo signal at the corresponding height by using decompression processing according to the selected ionospheric phase screen height.

[0074] An ionospheric scintillation phase addition module for adding the ionospheric scintillation phase to the azimuth echo signal at the corresponding spatial position.

[0075] A compression processing module for obtaining the azimuth spectrum data affected by the ionosphere by using compression processing.

[0076] A loop module for repeating the processes of obtaining the echo signal, adding the ionospheric scintillation phase, and compression processing until all the ionospheric scintillation phases generated at all heights are added to the azimuth echo.

[0077] An image output module for obtaining the azimuth image data affected by the scintillation phase of the multi-layer phase screen by using the inverse Fourier transform.

[0078] An ionospheric scintillation effect error modeling device based on a multi-phase screen model, comprising:

[0079] A memory: for storing a computer program for implementing the method for modeling the ionospheric scintillation effect error based on the multi-phase screen model as described above;

[0080] A processor, for implementing the method for modeling the ionospheric scintillation effect error based on the multi-phase screen model when executing the computer program.

[0081] A computer-readable storage medium storing a computer program, and the computer program, when executed by a processor, can implement a method for modeling the ionospheric scintillation effect error based on a multi-phase screen model.

[0082] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0083] 1. The present invention has the characteristic of high error modeling accuracy. Due to the adoption of the multi-phase screen assumption, compared with the single-phase screen assumption, it can be applied to the situation when the scintillation is strong and the thickness of the irregular layer is large, and has higher error modeling accuracy.

[0084] 2. The present invention has the characteristic of a simple model. Since the modeling method adopts a straight-line propagation model, compared with the parabolic equation approximation that needs to consider the diffraction effect of the ionosphere, it is a very simple error model.

[0085] 3. The present invention has the characteristic of a wide modeling range. Since the error modeling method is linear for each point target in the SAR image, this modeling method can realize the error modeling of the entire SAR image affected by the ionospheric scintillation effect.

[0086] 4. The present invention has the characteristic of strong scalability. Since the height of the phase screen and the number of phase screens in the model can be flexibly set according to the actual ionospheric distribution state, this error modeling method has extremely strong scalability.

[0087] 5. The present invention has the characteristic of high calculation efficiency. This method adopts a fast FFT algorithm and can realize the rapid error modeling of the scintillation effect only through seven steps.

[0088] 6. The present invention uses a multi-phase screen model to simulate the ionospheric electron density irregularities, obtains the radar echoes received at different phase screen heights through decompression processing and decompression phase replacement, and adds the scintillation phases of the phase screens at different heights to the radar echoes by multiplying the corresponding spatial positions, so as to realize the accurate modeling of the ionospheric scintillation effect error of the spaceborne synthetic aperture radar (SAR) under distributed targets. Description of the Drawings

[0089] Figure 1 is the method flow chart of the present invention.

[0090] Figure 2 is the SAR azimuth image data used in the embodiment.

[0091] Figure 3 is the h generated in the embodiment 1 ionospheric scintillation phase at altitude.

[0092] Figure 4 is the h generated in the embodiment 2 ionospheric scintillation phase at altitude.

[0093] Figure 5 is the azimuth image data affected by the multi-layer phase screen scintillation phase obtained by adopting the present invention in the embodiment. Detailed implementation manners

[0094] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and embodiments.

[0095] An ionospheric scintillation effect error modeling method based on a multi-phase screen model, the error modeling object of this method is the one-dimensional azimuth image data of SAR, namely one-dimensional complex vector, denoted as S, and assume the size of S is N a ×1, N a represents the number of sampling points in the azimuth direction, PRF represents the pulse repetition frequency of the radar, V ref represents the radar equivalent velocity with the scene center as the reference. Different azimuth sampling points correspond to different azimuth positions, and the distance interval between two adjacent azimuth positions is V ref / PRF.

[0096] See Figure 1 , an ionospheric scintillation effect error modeling method based on a multi-phase screen model, includes the following steps:

[0097] Step 1, generate phase screens: According to the radar system parameters and the ionospheric parameters at altitudes h 1 、h 2 …h n respectively generate phase screens at altitudes h 1 、h 2 …h n to obtain the ionospheric scintillation phases at altitudes h 1 、h 2 …h n Specifically: Specifically:

[0098] Step 1.1, calculate the azimuth sampling parameters of the phase screen:

[0099] h i The phase screen in altitude is expressed as (i = 1, 2... n, where n represents the number of phase screens), and the phase screens at different altitudes are of the same size, all being N a ×1, N a represents the number of sampling points in the azimuth direction. Different azimuth sampling points correspond to different azimuth positions. The spatial interval between two adjacent azimuth sampling points of the phase screens at all altitudes is the same, all being d:

[0100]

[0101] In the formula, V ref represents the radar equivalent velocity with the scene center as the reference, and PRF represents the pulse repetition frequency of the radar;

[0102] Step 1.2, calculate the ionospheric scintillation phase:

[0103] According to the radar system parameters and the azimuth sampling parameters of the phase screen obtained in the above Step 1.1, generate the phase screens at altitudes h 1 、h 2 …h n to obtain the ionospheric scintillation phases at altitudes h 1 、h 2 …h n In the present invention, for the specific content of generating the phase screen, please refer to the Ph.D. thesis of Li Zhuo, "Research on Error Compensation Methods for Ionospheric Effects in Spaceborne VHF / UHF-SAR", pages 25 to 27;

[0104] The ionospheric scintillation phase at altitude h

[0105] h i is specifically expressed as: Specifically, it is expressed as:

[0106]

[0107] In the formula, represents the value at the (1, 1) position in the ionospheric scintillation phase at altitude h i , represents the value at the (N i , 1) position in the ionospheric scintillation phase at altitude h a .

[0108] Step 2, obtain the azimuth spectral data: Perform a fast Fourier transform (FFT) on the azimuth image data S column by column to obtain the azimuth spectral data S FFT , specifically:

[0109] Step 2.1, perform a fast Fourier transform (FFT) on the azimuth image data S column by column:

[0110] Let the one-dimensional azimuth image data S of the SAR be:

[0111]

[0112] where S 11 represents the value at the (1, 1) position in the image data, represents the value at the (N a , 1) position in the image data;

[0113] Perform a fast Fourier transform (FFT) on the one-dimensional azimuth image data S of the SAR column by column to obtain the azimuth spectrum data S FFT as:

[0114]

[0115] where represents the value at the (1, 1) position in the azimuth spectrum data, represents the value at the (N a , 1) position in the azimuth spectrum data, and FFT(·) represents performing a fast Fourier transform on the matrix column by column;

[0116] In the present invention, for the specific content of the fast Fourier transform (FFT) and the fast inverse Fourier transform (IFFT), please refer to the book "Synthetic Aperture Radar Imaging Algorithms and Implementations" published by Electronic Industry Press in June 2012, written by Ian G Cumming, etc. and translated by Hong Wen, etc., pages 18 to 19;

[0117] Step 2.2, set the initial value of the azimuth spectrum data affected by the scintillation phase and the initial value of the loop parameter i:

[0118]

[0119] Step 3, obtain the echo signal at the phase screen height: According to the radar system parameters, calculate the reference slant range i corresponding to the height h Calculate the azimuth decompression phase at the height h i based on this reference slant range Add this azimuth decompression phase to the azimuth spectrum data obtained in Step 2 to obtain the azimuth echo spectrum at the height h i Add this azimuth echo spectrum at the height h to i obtain the azimuth echo spectrum at the height h Perform an Inverse Fast Fourier Transform (IFFT) column by column to obtain h i Echo signal in the azimuth direction at a certain height Specifically:

[0120] Step 3.1: Calculate h according to the radar system parameters i The corresponding reference slant range at a certain height :

[0121]

[0122] In the formula, R 0 represents the reference slant range of the scene center, h i is the height of the i-th phase screen, and H represents the flight height of the radar when passing through the scene center point;

[0123] Step 3.2: Calculate the azimuth frequency f at each azimuth position of the azimuth spectrum data according to the radar system parameters a :

[0124]

[0125] Step 3.3: Based on the h i corresponding reference slant range at a certain height calculated in Step 3.1 and the azimuth frequency f a calculated at each azimuth position in Step 3.2, the azimuth decompressed phase i at a certain height can be calculated :

[0126]

[0127] In the formula, represents the value at the (1, 1) position in the azimuth frequency f a , and represents the value at the (N a , 1) position in the azimuth frequency f a ;

[0128] Step 3.4: Multiply the azimuth decompressed phase i at a certain height calculated in Step 3.3 by the azimuth spectrum data S obtained in Step 2 to get FFT the azimuth echo spectrum i at a certain height :

[0129]

[0130] In the formula, j represents the imaginary unit, that is Denote h i Azimuth decompression phase in height The value at the (1, 1) position in Denote h i Azimuth decompression phase in height At the (N a , 1) position;

[0131] Step 3.5, Take the h calculated in Step 3.4 i Azimuth echo spectrum in height Perform an inverse fast Fourier transform (IFFT) column by column to obtain h i Azimuth echo signal in height :

[0132]

[0133] In the formula, Denote h i The value at the (1, 1) position in the azimuth echo signal in height, Denote h i At the (N a , 1) position in the azimuth echo signal in height, IFFT(·) represents performing an inverse fast Fourier transform column by column on the matrix.

[0134] Step 4, Add h i Ionospheric scintillation phase in height: Take the h obtained in Step 3 i Azimuth echo signal in height And add the h obtained in Step 1 i Ionospheric scintillation phase in height To obtain h i Azimuth echo signal in height affected by the ionosphere Specifically:

[0135]

[0136] Step 5, Azimuth signal compression: Take the h obtained in Step 4 i Azimuth echo signal in height affected by the ionosphere Perform a fast Fourier transform (FFT) column by column to obtain h i Azimuth echo spectrum in height affected by the ionosphere Then divide this h i Azimuth echo spectrum in height affected by the ionosphere By the h calculated in Step 3 i Azimuth decompression phase in height To obtain h iAzimuth spectrum data affected by the ionosphere in altitude The obtained h i Azimuth spectrum data affected by the ionosphere in altitude Execute a loop and repeatedly apply it in steps 3 to 5 until all phase screens at the set altitudes are added to the azimuth echo data, obtaining the azimuth spectrum data S affected by the scintillation phase of the multi-layer phase screen I_FFT_all , specifically:

[0137] Step 5.1, azimuth Fourier transform:

[0138] The h obtained in step 4 i Azimuth echo signal affected by the ionosphere in altitude Perform a fast Fourier transform (FFT) column by column to obtain h i Azimuth echo spectrum affected by the ionosphere in altitude :

[0139]

[0140] In the formula, represents the value at the (1, 1) position in h i Azimuth echo spectrum affected by the ionosphere in altitude ; represents the value at the (N i Azimuth echo spectrum affected by the ionosphere in altitude , 1) position; a

[0141] Step 5.2, azimuth frequency domain compression:

[0142] Divide the h obtained in step 5.1 i Azimuth echo spectrum affected by the ionosphere in altitude by the h calculated in step 3 i Azimuth decompression phase in altitude to obtain h i Azimuth spectrum data affected by the ionosphere in altitude :

[0143]

[0144] Step 5.3, execute a loop:

[0145] Repeatedly apply the azimuth spectrum data obtained in step 5.2 in steps 3 to 5, and check whether the loop parameter i exceeds the upper limit:

[0146] ​If \(i\geq n\), the azimuth spectrum data affected by the scintillation phase of the multi-layer phase screen is obtained. :

[0147]

[0148] If \(i < n\), update the loop parameter \(i\) and return to step 3:

[0149]

[0150] Step 6, inverse Fourier transform: Perform a fast inverse Fourier transform (IFFT) column by column on the azimuth spectrum data \(S\) affected by the scintillation phase of the multi-layer phase screen obtained in step 5 to obtain the azimuth image data \(S\) affected by the scintillation phase of the multi-layer phase screen, specifically: I_FFT_all where \(\) represents the value at the \((1, 1)\) position in the one-dimensional azimuth image data affected by the scintillation phase of the multi-layer phase screen, and \(\) represents the value at the \((N, 1)\) position in the one-dimensional azimuth image data affected by the scintillation phase of the multi-layer phase screen. I_s :

[0151]

[0152] In the formula, represents the value at the \((1, 1)\) position in the one-dimensional azimuth image data affected by the scintillation phase of the multi-layer phase screen, and represents the value at the \((N\) a , 1) position in the one-dimensional azimuth image data affected by the scintillation phase of the multi-layer phase screen.

[0153] An ionospheric scintillation effect error modeling system based on a multi-phase screen model includes:

[0154] A phase screen generation module for generating a phase screen according to the selected ionospheric phase screen height to obtain the ionospheric scintillation phase at the corresponding height;

[0155] An echo signal acquisition module for obtaining the azimuth echo signal at the corresponding height by using decompression processing according to the selected ionospheric phase screen height;

[0156] An ionospheric scintillation phase addition module for adding the ionospheric scintillation phase to the azimuth echo signal at the corresponding spatial position;

[0157] A compression processing module for obtaining the azimuth spectrum data affected by the ionosphere by using compression processing;

[0158] A loop module for repeating the processes of obtaining the echo signal, adding the ionospheric scintillation phase, and compression processing until all the ionospheric scintillation phases generated at all heights are added to the azimuth echo;

[0159] An image output module for obtaining the azimuth image data affected by the scintillation phase of the multi-layer phase screen by using inverse Fourier transform.

[0160] An ionospheric scintillation effect error modeling device based on a multi-phase screen model, comprising:

[0161] A memory: for storing a computer program for implementing the ionospheric scintillation effect error modeling method based on the multi-phase screen model described above;

[0162] A processor, configured to implement the ionospheric scintillation effect error modeling method based on the multi-phase screen model when executing the computer program.

[0163] The so-called processor may be a Central Processing Unit (CPU), or may also be other general-purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field-Programmable Gate Arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc. The processor is the control center of the ionospheric scintillation effect error modeling device based on the multi-phase screen model, and uses various interfaces and lines to connect all parts of the ionospheric scintillation effect error modeling device based on the multi-phase screen model.

[0164] When the processor executes the computer program, it implements the steps of the above-mentioned ionospheric scintillation effect error modeling method based on the multi-phase screen model. For example: generating a phase screen: according to the radar system parameters and the ionospheric parameters at heights h 1 、h 2 …h n respectively generate phase screens at heights h 1 、h 2 …h n to obtain the ionospheric scintillation phases at heights h 1 、h 2 …h n at heights h Obtaining azimuth spectrum data: performing a fast Fourier transform (FFT) on the azimuth image data S column by column to obtain the azimuth spectrum data S FFT ; obtaining the echo signal at the phase screen height: according to the radar system parameters, calculating the corresponding reference slant range at height h i Calculating the azimuth decompressed phase at height h according to this reference slant range i at height h Adding the azimuth decompressed phase to the azimuth spectrum data to obtain h i Echo spectrum in the upper azimuth direction at altitude Regarding this h i Echo spectrum in the upper azimuth direction at altitude Perform fast inverse Fourier transform (IFFT) column by column to obtain h i Echo signal in the upper azimuth direction at altitude Add h i Ionospheric scintillation phase at altitude: Regarding h i Echo signal in the upper azimuth direction at altitude Add h i Ionospheric scintillation phase at altitude to obtain h i Echo signal in the azimuth direction affected by the ionosphere at altitude Azimuth signal compression: Regarding h i Echo signal in the azimuth direction affected by the ionosphere at altitude Perform fast Fourier transform (FFT) column by column to obtain h i Echo spectrum in the azimuth direction affected by the ionosphere at altitude Then regarding this h i Echo spectrum in the azimuth direction affected by the ionosphere at altitude divide by h i Azimuth decompression phase at altitude to obtain h i Spectrum data in the azimuth direction affected by the ionosphere at altitude Regarding the obtained h i Spectrum data in the azimuth direction affected by the ionosphere at altitude Execute a loop until all phase screens at the set altitudes are added to the azimuth echo data, to obtain the azimuth spectrum data S affected by the multi-layer phase screen scintillation phase I_FFT_all ; Inverse Fourier transform: Regarding the azimuth spectrum data S affected by the multi-layer phase screen scintillation phase I_FFT_all Perform fast inverse Fourier transform (IFFT) column by column to obtain the azimuth image data S affected by the multi-layer phase screen scintillation phase I_s .

[0165] Alternatively, when the processor executes the computer program, it implements the functions of each module in the above system. For example: a phase screen generation module, which is used to generate a phase screen according to the selected ionospheric phase screen height, and obtain the ionospheric scintillation phase at the corresponding height; an echo signal acquisition module, which uses decompression processing according to the selected ionospheric phase screen height to obtain the azimuth echo signal at the corresponding height; an ionospheric scintillation phase addition module, which adds the ionospheric scintillation phase to the azimuth echo signal according to the spatial corresponding position; a compression processing module, which uses compression processing to obtain the azimuth spectral data affected by the ionosphere; a loop module, which repeats the processes of obtaining the echo signal, adding the ionospheric scintillation phase, and compression processing until all the ionospheric scintillation phases at the generated heights are added to the azimuth echo; an image output module, which uses inverse Fourier transform to obtain the azimuth image data affected by the multi-layer phase screen scintillation phase.

[0166] Exemplarily, the computer program can be divided into one or more modules / units. The one or more modules / units are stored in the memory and executed by the processor to complete the present invention. The one or more modules / units can be a series of computer program instruction segments capable of completing preset functions, and the instruction segments are used to describe the execution process of the computer program in the ionospheric scintillation effect error modeling device based on the multi-phase screen model. For example, the computer program can be divided into a phase screen generation module, an echo signal acquisition module, an ionospheric scintillation phase addition module, a compression processing module, a loop module, and an image output module. The specific functions of each module are as follows: a phase screen generation module, which is used to generate a phase screen according to the selected ionospheric phase screen height, and obtain the ionospheric scintillation phase at the corresponding height; an echo signal acquisition module, which uses decompression processing according to the selected ionospheric phase screen height to obtain the azimuth echo signal at the corresponding height; an ionospheric scintillation phase addition module, which adds the ionospheric scintillation phase to the azimuth echo signal according to the spatial corresponding position; a compression processing module, which uses compression processing to obtain the azimuth spectral data affected by the ionosphere; a loop module, which repeats the processes of obtaining the echo signal, adding the ionospheric scintillation phase, and compression processing until all the ionospheric scintillation phases at the generated heights are added to the azimuth echo; an image output module, which uses inverse Fourier transform to obtain the azimuth image data affected by the multi-layer phase screen scintillation phase.

[0167] The error modeling device for ionospheric scintillation effects based on the multi-phase screen model may be a computing device such as a desktop computer, a notebook, a palm computer, or a cloud server. The error modeling device for ionospheric scintillation effects based on the multi-phase screen model may include, but is not limited to, a processor and a memory. Those skilled in the art can understand that the above are examples of the error modeling device for ionospheric scintillation effects based on the multi-phase screen model, and do not constitute a limitation on the error modeling device for ionospheric scintillation effects based on the multi-phase screen model. It may include more components than the above, or combine some components, or different components. For example, the error modeling device for ionospheric scintillation effects based on the multi-phase screen model may also include input / output devices, network access devices, buses, etc.

[0168] The memory may be used to store the computer program and / or module. By running or executing the computer program and / or module stored in the memory, and calling the data stored in the memory, the processor realizes various functions of the error modeling device for ionospheric scintillation effects based on the multi-phase screen model.

[0169] The memory may mainly include a program storage area and a data storage area. Among them, the program storage area may store an operating system, application programs required for at least one function (such as a sound playback function, an image playback function, etc.); the data storage area may store data created according to the use of the mobile phone (such as audio data, phone book, etc.). In addition, the memory may include high-speed random access memory, and may also include non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) card, a Flash Card, at least one magnetic disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0170] The present invention also provides a computer-readable storage medium storing a computer program, and when the computer program is executed by a processor, the steps of the error modeling method for ionospheric scintillation effects based on the multi-phase screen model are realized.

[0171] If the modules / units integrated in the error modeling system for ionospheric scintillation effects based on the multi-phase screen model are implemented in the form of software functional units and sold or used as independent products, they may be stored in a computer-readable storage medium.

[0172] The present invention realizes all or part of the processes in the above-mentioned ionospheric scintillation effect error modeling method based on the multi-phase screen model, and can also be completed by instructing relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by a processor, the steps of the above-mentioned ionospheric scintillation effect error modeling method based on the multi-phase screen model can be realized. Among them, the computer program includes computer program code, and the computer program code can be in the form of source code, object code, executable file or preset intermediate form, etc.

[0173] The computer-readable storage medium may include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal, and software distribution medium, etc.

[0174] It should be noted that the content included in the computer-readable storage medium can be appropriately increased or decreased according to the requirements of legislation and patent practice within the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable storage medium does not include electrical carrier signals and telecommunication signals.

[0175] The present invention will be further described in detail below in conjunction with embodiments.

[0176] This embodiment provides an ionospheric scintillation effect error modeling method based on the multi-phase screen model. The embodiment uses the one-dimensional azimuth image data of SAR point targets obtained by simulation, as Figure 2 shown. The parameters involved in the processing process are shown in Table 1:

[0177] Table 1 Embodiment Parameters

[0178]

[0179] This embodiment specifically includes the following steps:

[0180] Step 1, generate a phase screen:

[0181] In the embodiment, two phase screens are generated at altitudes of h 1 = 150 km and h 2 = 350 km. Specifically:

[0182] Step 1.1, calculate the azimuth sampling parameters of the phase screen:

[0183] h 1 The phase screen at the altitude is expressed as h 2The phase screen at altitude is expressed as The phase screens at the two heights have the same size, both 3864×1. According to the parameters in Table 1, the spatial intervals between two adjacent azimuth sampling points of the phase screens at the two heights are calculated by formula (1) to be d=3.7809m;

[0184] Step 1.2, calculate the ionospheric scintillation phase:

[0185] According to the parameters in Table 1 and the phase screen azimuth sampling parameters obtained above, according to Li Zhuo's doctoral dissertation of Beijing University of Aeronautics and Astronautics [Study on the Error Compensation Method of Spaceborne VHF / UHF-SAR Ionospheric Effect], pages 25 to 27, h is generated respectively. 1 、h 2 The phase screen at height, h 1 、h 2 Ionospheric scintillation phase at altitude like Figure 3 , Figure 4 shown.

[0186] Step 2: Get the azimuth spectrum data:

[0187] Step 2.1: Perform fast Fourier transform (FFT) on the one-dimensional azimuth image data S of the SAR point target by column to obtain the azimuth spectrum data S FFT ;

[0188] Step 2.2, set the initial value of the azimuth spectrum data after being affected by the ionosphere And the initial value of the loop parameter i: i=1.

[0189] Step 3, obtain the echo signal at the phase screen height:

[0190] According to the parameters in Table 1, calculate h i Reference slope distance corresponding to the height Based on this reference slope distance, h is calculated. i Azimuth decompression phase in altitude Add the azimuth decompressed phase to the azimuth spectrum data On, get h i Azimuth echo spectrum in altitude Then put this h i Azimuth echo spectrum in altitude Perform inverse fast Fourier transform (IFFT) column by column to get h i Altitude direction echo signal Specifically:

[0191] Step 3.1, according to the parameters in Table 1, calculate h according to formula (7): i Reference slope distance corresponding to the height

[0192] In step 3.2, the spatial interval d between two adjacent azimuth sampling points of the phase screen obtained in step 1 is 3.7809 m, and the azimuth frequency f at each azimuth position is calculated according to Equation (8). a ;

[0193] In step 3.3, according to the calculated h i the reference slant range corresponding to the height and the azimuth frequency f of the azimuth spectrum data at each azimuth position a , the azimuth decompressed phase at height h is calculated according to Equation (9). i the azimuth decompressed phase at height h

[0194] In step 3.4, the azimuth decompressed phase at height h calculated according to Equation (10). i the azimuth decompressed phase at height h is multiplied by the azimuth spectrum data S FFT to obtain the azimuth echo spectrum at height h i the azimuth echo spectrum at height h

[0195] In step 3.5, the azimuth echo spectrum at height h i is subjected to fast inverse Fourier transform (IFFT) column by column according to Equation (11) to obtain the azimuth echo signal at height h the azimuth echo signal at height h i

[0196] In step 4, the ionospheric scintillation phase at height h is added: i The azimuth echo signal at height h obtained in step 3 is added with the ionospheric scintillation phase at height h according to Equation (12).

[0197] The azimuth echo signal at height h obtained in step 3 is added with the ionospheric scintillation phase at height h according to Equation (12). i the azimuth echo signal at height h to obtain the azimuth echo signal affected by the ionosphere at height h i the ionospheric scintillation phase at height h to obtain the azimuth echo signal affected by the ionosphere at height h i the azimuth echo signal affected by the ionosphere at height h

[0198] In step 5, azimuth signal compression:

[0199] In step 5.1, azimuth Fourier transform:

[0200] The azimuth echo signal affected by the ionosphere at height h obtained in step 4 is subjected to fast Fourier transform (FFT) column by column according to Equation (13) to obtain the azimuth echo spectrum affected by the ionosphere at height h i the azimuth echo signal affected by the ionosphere at height h the azimuth echo spectrum affected by the ionosphere at height h i the azimuth echo spectrum affected by the ionosphere at height h​

[0201] Step 5.2, azimuth frequency domain compression:

[0202] Divide the azimuth echo spectrum i after being affected by the ionosphere in altitude by h by h i the azimuth decompression phase in altitude to obtain h i the azimuth spectrum data after being affected by the ionosphere in altitude

[0203] Step 5.3, execute the loop:

[0204] Check whether the loop parameter i is greater than or equal to 2:

[0205] If i≥2, obtain the azimuth spectrum data affected by the scintillation phase of the multi-layer phase screen

[0206] If i<2, update the loop parameter i = i + 1, and then return to Step 3.

[0207] Step 6, inverse Fourier transform:

[0208] Perform a fast inverse Fourier transform (IFFT) on the azimuth spectrum data S affected by the scintillation phase of the multi-layer phase screen obtained in Step 5 I_FFT_all column by column to obtain the azimuth image data S affected by the scintillation phase of the multi-layer phase screen I_s , as Figure 5 shown.

[0209] Compare Figure 2 the one-dimensional azimuth image data of the SAR point target obtained by simulation shown with the Figure 5 azimuth image data affected by the scintillation phase of the multi-layer phase screen obtained according to the present invention, it can be seen that: Figure 5 Higher-order random phase errors appear, causing defocusing of the SAR azimuth signal. It can be seen that the method for modeling the ionospheric scintillation effect error based on the multi-phase screen model proposed by the present invention can better reflect the influence of the ionospheric scintillation effect on the SAR echo signal.

[0210] In summary, the above embodiments illustrate that a method for modeling the ionospheric scintillation effect error based on the multi-phase screen model proposed by the present invention can achieve accurate error modeling of the SAR image affected by the ionospheric scintillation effect.

Claims

1. A method for modeling the error of ionospheric scintillation effect based on a multi-phase screen model, characterized in that, it includes the following steps: Step 1, generate a phase screen: According to the radar system parameters and the ionospheric parameters at heights h 1 , h 2 …h n , respectively generate phase screens at heights h 1 , h 2 …h n , and obtain the ionospheric scintillation phases at heights h 1 , h 2 …h n ​ Step 2, obtaining azimuth spectrum data: performing a fast Fourier transform (FFT) on the azimuth image data S column by column to obtain the azimuth spectrum data S FFT ; Step 3, obtain the echo signal at the height of the phase screen: Calculate h according to the radar system parameters i The corresponding reference slant range at the height of h Calculate the azimuth decompression phase at the height of h according to this reference slant range i The azimuth decompression phase at the height of h Add this azimuth decompression phase To the azimuth spectrum data obtained in Step 2 To obtain the azimuth echo spectrum at the height of h i The azimuth echo spectrum at the height of h Perform a fast inverse Fourier transform (IFFT) on this azimuth echo spectrum at the height of h i The azimuth echo spectrum at the height of h By columns to obtain the azimuth echo signal at the height of h i The azimuth echo signal at the height of h Step 4, add h i Ionospheric scintillation phase in altitude: The h obtained in Step 3 i Echo signal in azimuth at altitude Add the h obtained in Step 1 i Ionospheric scintillation phase in altitude Obtain h i Echo signal in azimuth affected by the ionosphere at altitude Step 5, azimuth signal compression: The h obtained in Step 4 i Azimuth echo signal affected by the ionosphere in altitude Perform fast Fourier transform (FFT) column by column to obtain h i Azimuth echo spectrum affected by the ionosphere in altitude Then divide this h i Azimuth echo spectrum affected by the ionosphere in altitude by the h calculated in Step 3 i Azimuth decompression phase in altitude to obtain h i Azimuth spectrum data affected by the ionosphere in altitude For the obtained h i Azimuth spectrum data affected by the ionosphere in altitude Execute a loop and repeatedly apply Steps 3 to 5 until all phase screens at the set altitudes are added to the azimuth echo data, obtaining the azimuth spectrum data S affected by the scintillation phase of the multi-layer phase screen I_FFT_all ; Step 6, Inverse Fourier transform: Perform an inverse fast Fourier transform (IFFT) column by column on the azimuth spectrum data S affected by the scintillation phase of the multi-layer phase screen obtained in Step 5 to obtain the azimuth image data S affected by the scintillation phase of the multi-layer phase screen I_FFT_all I_s .​ 2. The method for modeling the error of ionospheric scintillation effect based on a multi-phase screen model according to claim 1, characterized in that, the process of generating the phase screen in step 1 includes: Step 1.1, calculating the azimuth sampling parameter of the phase screen: h i The phase screen in height is expressed as (i = 1, 2... n, where n represents the number of phase screens). The phase screens at different heights are of the same size, all being N a × 1, N a representing the number of sampling points in the azimuth direction. Different azimuth sampling points correspond to different azimuth positions. The spatial intervals between two adjacent azimuth sampling points of the phase screens at all heights are the same, all being d: Where, V ref represents the radar equivalent velocity with reference to the scene center, and PRF represents the pulse repetition frequency of the radar; Step 1.2, calculating the ionospheric scintillation phase: According to the radar system parameters and the azimuth sampling parameters of the phase screen obtained in the above step 1.1, generate h 1 , h 2 …h n phase screens at different heights, and obtain the ionospheric scintillation phases at heights of h 1 , h 2 …h n ​ h i Ionospheric scintillation phase in altitude Specifically expressed as: In the formula, represents h i the value at the (1, 1) position in the ionospheric scintillation phase at height h, represents h i the value at the (N a , 1) position in the ionospheric scintillation phase at height h.

3. The method for modeling the error of ionospheric scintillation effect based on a multi-phase screen model according to claim 1, characterized in that, the process of obtaining the azimuth spectral data in step 2 includes: Step 2.1, performing a fast Fourier transform on the azimuth image data S column by column: Let the one-dimensional azimuth image data S of the SAR be: Where S 11 represents the value at the (1, 1) position in the image data, represents the value at the (N a , 1) position in the image data; Perform a fast Fourier transform (FFT) on the one-dimensional azimuth image data S of the SAR column by column to obtain the azimuth spectrum data S FFT It is: In the formula, represents the value at the (1, 1) position in the azimuth spectrum data, represents the value at the (N a , 1) position of the azimuth spectrum data, and FFT(·) represents the fast Fourier transform of the matrix column by column; Step 2.2, set the initial value of the azimuth spectrum data affected by the flashing phase and the initial value of the loop parameter i: i＝1 (6)。 4. The method for modeling the error of ionospheric scintillation effect based on a multi-phase screen model according to claim 1, characterized in that, the process of obtaining the echo signal at the phase screen height in step 3 includes: Step 3.1, calculate h according to the radar system parameters i The corresponding reference slant range in altitude where R 0 represents the reference slant range of the scene center, h i is the height of the i-th phase screen, and H represents the flight height of the radar when passing through the scene center point; Step 3.2, calculate the azimuth frequency f of the azimuth spectrum data at each azimuth position according to the radar system parameters a : Step 3.3, according to the h obtained by calculation in Step 3.1 i The corresponding reference slant range in height and the azimuth frequency f at each azimuth position obtained by calculation in Step 3.2 a , the azimuth decompression phase at height h can be calculated i ​ In the formula, represents the value at the (1, 1) position in the azimuth frequency f a , represents the value at the (N a , 1) position in the azimuth frequency f a ; Step 3.4, multiply the h i azimuth decompression phase in height by the azimuth spectrum data S obtained in Step 2 FFT to obtain h i azimuth echo spectrum in height In the formula, j represents the imaginary unit, that is represents h i the azimuth decompression phase in height the value at the (1, 1) position in represents h i the azimuth decompression phase in height the value at the (N a , 1) position; Step 3.5, take the h calculated in Step 3.4 i Echo spectrum in the upper azimuth direction of height Perform fast inverse Fourier transform (IFFT) column by column to obtain h i Echo signal in the upper azimuth direction of height In the formula, represents h i the value at the (1, 1) position in the height azimuth echo signal, represents h i the value at the (N a , 1) position in the height azimuth echo signal, and IFFT(·) represents the fast inverse Fourier transform of the matrix column by column.

5. The method for modeling the error of ionospheric scintillation effect based on a multi-phase screen model according to claim 1, characterized in that, In step 4, h is added i The process of the ionospheric scintillation phase in altitude is as follows: Add the azimuth echo signal in the height direction obtained in step 3 with the h i in the height direction and add the ionospheric scintillation phase in the height direction obtained in step 1 i to obtain the azimuth echo signal in the height direction affected by the ionosphere h i Specifically, it is expressed as: Specifically, it is expressed as:

6. The method for modeling the error of ionospheric scintillation effect based on a multi-phase screen model according to claim 1, characterized in that, the process of azimuth signal compression in step 5 includes: Step 5.1, azimuth Fourier transform: The azimuth echo signal h obtained in step 4 i after being affected by the ionosphere in height Perform fast Fourier transform (FFT) column by column to obtain h i azimuth echo spectrum after being affected by the ionosphere in height In the formula, represents h i the azimuth echo spectrum after being affected by the ionosphere in terms of height the value at the (1, 1) position in represents h i the azimuth echo spectrum after being affected by the ionosphere in terms of height the value at the (N a , 1) position in; Step 5.2, azimuth frequency domain compression: Divide the azimuth echo spectrum i after being affected by the ionosphere in height by the h calculated in step 3 i of the azimuth decompression phase in height to obtain h i of the azimuth spectrum data after being affected by the ionosphere in height Step 5.3, performing a loop: The azimuth spectrum data obtained in Step 5.2 Repeat the application from Step 3 to Step 5 and check whether the loop parameter i exceeds the upper limit: If \(i\geq n\), the azimuth spectrum data \(S\) affected by the scintillation phase of the multi-layer phase screen is obtained I_FFT_all : If i < n, update the loop parameter i and return to step 3: i = i + 1 (16).

7. The method for modeling the error of ionospheric scintillation effect based on a multi-phase screen model according to claim 1, characterized in that, the process of inverse Fourier transform in step 6 is: The azimuth spectrum data S affected by the scintillation phase of the multi-layer phase screen obtained in step 5 I_FFT_all Perform a fast inverse Fourier transform (IFFT) column by column to obtain the one-dimensional azimuth image data S affected by the scintillation phase of the multi-layer phase screen I_s , specifically: In the formula, represents the value at the (1, 1) position in the one-dimensional azimuth image data affected by the multi-layer phase screen scintillation phase, represents the value at the (N a , 1) position in the one-dimensional azimuth image data affected by the multi-layer phase screen scintillation phase.

8. An ionospheric scintillation effect error modeling system based on a multi-phase screen model, characterized in that, it includes: A phase screen generation module, which is used to generate a phase screen according to the selected ionospheric phase screen height, and obtain the ionospheric scintillation phase at the corresponding height; An echo signal acquisition module, which uses decompression processing according to the selected ionospheric phase screen height to obtain the azimuth echo signal at the corresponding height; An ionospheric scintillation phase addition module, which adds the ionospheric scintillation phase to the azimuth echo signal according to the spatial corresponding position; A compression processing module, which uses compression processing to obtain the azimuth spectral data affected by the ionosphere; A loop module, which repeats the processes of obtaining the echo signal, adding the ionospheric scintillation phase, and compression processing until all the ionospheric scintillation phases generated at all heights are added to the azimuth echo; An image output module, which uses inverse Fourier transform to obtain the azimuth image data affected by the scintillation phases of multiple phase screens.

9. An ionospheric scintillation effect error modeling device based on a multi-phase screen model, characterized in that, it includes: A memory: used to store a computer program for implementing the method for modeling the error of ionospheric scintillation effect based on a multi-phase screen model according to any one of claims 1-7; A processor, which is used to implement the method for modeling the error of ionospheric scintillation effect based on a multi-phase screen model according to any one of claims 1-7 when executing the computer program.

10. A computer-readable storage medium, characterized in that, it includes: the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, it can implement a method for modeling the ionospheric scintillation effect error based on a multi-phase screen model according to any one of claims 1-7.

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