Universal multi-mode SAR large-scale scene deception jamming generation method and device

Abstract

The invention provides a universal multi-mode SAR large-scale scene deception jamming generation method and device, and belongs to the field of electronic support system synthetic aperture radar confrontation. Comprising the following steps that: a jammer detects and receives SAR platform, SAR antenna and SAR signal parameters of an SAR radar entering a detection range; and in the azimuth time-frequency transform domain, forming a changing Doppler center azimuth support domain corresponding to each mode. In a two-dimensional frequency domain, a strip SAR azimuth frequency domain deception jamming algorithm is adopted to efficiently construct cross coupling terms, and a false scene related frequency response function of each mode is formed. And in the azimuth frequency domain, azimuth frequency spectrum aliasing processing of the false scene related frequency response function is completed. And multiplying the related frequency response function of the jammer by the related frequency response function of the false scene to obtain a multi-mode SAR jamming frequency response function, and performing interception modulation through DRFM pulse by pulse to generate deception jamming. According to the method, the interference precision of the multi-mode SAR deception interference is ensured.

Description

Technical Field

[0001] The present invention belongs to the field of synthetic aperture radar countermeasure for electronic support measures (ESM), and particularly relates to a general multi-mode SAR large-scene deception jamming generation method and device. Background Art

[0002] Synthetic aperture radar (SAR) has been widely used in the field of high-resolution imaging due to its all-weather, all-day, and strong penetration capabilities. However, with the improvement of the resolution and coverage of SAR systems, the research on its interference technology has gradually attracted attention, especially the high-fidelity and low-power deception jamming technology. Modern SAR systems have the ability to adjust the beam scanning direction, and the echo data of its various working modes (such as spotlight, sliding spotlight, and TOPSAR modes) have unique time-frequency characteristics, which makes the implementation of deception jamming more complex. However, most traditional SAR deception jamming methods focus on the generation of interference signals for strip-mode SAR. With the increasing demand for resolution and observation range in SAR observation tasks, the vast majority of SAR systems are now equipped with diverse working modes. Different SAR working modes bring time-frequency characteristics different from those of the strip mode to their echo data, making the implementation process of SAR deception jamming more complex and challenging.

[0003] Existing deception jamming generation schemes have some limitations. For example, Chinese invention patent CN107133385B proposes to generate multi-mode SAR deception jamming signals by filtering the interference frequency response function of the strip mode. However, this method lacks a unified multi-mode representation form, and pre-generating wide-beam strip SAR data wastes storage resources. The time-varying FIR filter also increases the computational burden and is difficult to apply to interference machines based on digital radio frequency memories. In addition, the time-domain deception jamming method based on template block division is suitable for large-scene deception, but it relies on inefficient integral operations and is limited to the TOPSAR mode.

[0004] In summary, there is an urgent need to develop an efficient and general multi-mode SAR deception jamming signal generation method to meet the application requirements in the field of high-resolution imaging. Summary of the Invention

[0005] To solve the problem that current SAR deception jamming methods are difficult to adapt to multi-mode SAR, the present invention proposes a general multi-mode SAR large-scene deception jamming generation method and device.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] The general multi-mode SAR large-scene deception jamming generation method includes the following steps:

[0008] Step 1: Use an interferer to intercept the platform, antenna, and signal parameters of the SAR radar entering the detection range, and select an SAR image template with complex backscattering coefficients according to the interference target requirements.

[0009] Step 2: In the azimuth time-frequency transform domain, introduce a frequency modulation term and a window function related to the sliding factor and the Doppler center change slope, and modulate the azimuth time-domain positions of the scattering points in the SAR image template onto the support domain function of the azimuth spectrum to form a variable Doppler center azimuth support domain corresponding to each mode.

[0010] Step 3: In the two-dimensional frequency domain, use the strip SAR azimuth frequency domain deception interference algorithm to construct cross-coupling terms and generate a false scene-related frequency response function for each mode.

[0011] Step 4: Use the conjugate function of the azimuth dechirp function to restore the Doppler history of the false scene-related frequency response function and complete the azimuth spectrum aliasing processing.

[0012] Step 5: Multiply the interferer-related frequency response function by the false scene-related frequency response function to obtain a multi-mode SAR interference frequency response function, and generate a deception interference signal by modulating each pulse through a digital radio frequency memory.

[0013] The present invention also provides a general multi-mode SAR large scene deception interference generation device, including the following modules:

[0014] A deception interference template generation module, which uses an interferer to intercept the platform, antenna, and signal parameters of the SAR radar entering the detection range, and selects an SAR image template with complex backscattering coefficients according to the interference target requirements.

[0015] A beam pointing control module, which in the azimuth time-frequency transform domain, introduces a frequency modulation term and a window function related to the sliding factor and the Doppler center change slope, and modulates the azimuth time-domain positions of the scattering points in the SAR image template onto the support domain function of the azimuth spectrum to form a variable Doppler center azimuth support domain corresponding to each mode.

[0016] A cross-coupling term unified construction module, which in the two-dimensional frequency domain, uses the strip SAR azimuth frequency domain deception interference algorithm to construct cross-coupling terms and generate a false scene-related frequency response function for each mode.

[0017] An azimuth aliasing construction module, which uses the conjugate function of the azimuth dechirp function to restore the Doppler history of the false scene-related frequency response function and complete the azimuth spectrum aliasing processing.

[0018] The deception jamming real-time generation module multiplies the frequency response function related to the jammer with the frequency response function related to the false scene to obtain the multi-mode SAR jamming frequency response function, and generates the deception jamming signal through pulse-by-pulse modulation by the digital radio frequency memory.

[0019] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, the steps of the above-mentioned general multi-mode SAR large-scene deception jamming generation method are implemented.

[0020] The present invention also provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the above-mentioned general multi-mode SAR large-scene deception jamming generation method are implemented.

[0021] Beneficial effects:

[0022] The innovation of the present invention lies in its large-range jamming ability for multi-mode SAR systems, ensuring accurate signal jamming in various modes. This accuracy benefits from the accurate modeling of signal characteristics in each mode.

[0023] In terms of operation efficiency, the present invention shows significant advantages. Its modulation process only involves complex multiplication and Fourier transform, which greatly improves the calculation speed and efficiency compared with the current methods that rely on real-time filtering and integral operations.

[0024] In addition, the present invention constructs a unified framework to standardize the jamming steps in different modes, using common parameters and modular design. This method not only reduces the differences between different modes but also improves the practicality and flexibility of multi-mode SAR jamming technology. Description of the drawings

[0025] Figure 1 is the slant range plane model of the sliding spotlight SAR;

[0026] Figure 2 is the slant range plane model diagram of the TOPSAR;

[0027] Figure 3 is the schematic diagram of the general multi-mode SAR large-scene deception jamming generation system of the present invention;

[0028] Figure 4 is the close-up image of the P1 false target point generated by the present invention against the sliding spotlight SAR;

[0029] Figure 5 is the close-up image of the P1 false target point generated by the present invention against the TOPSAR;

[0030] Figure 6a It is a cross-sectional view of the false target point P1 generated by counteracting the sliding spotlight SAR;

[0031] Figure 6b It is a cross-sectional view of the false target point P2 generated by counteracting the sliding spotlight SAR;

[0032] Figure 6c It is a cross-sectional view of the false target point P3 generated by counteracting the sliding spotlight SAR;

[0033] Figure 7a It is a cross-sectional view of the false target point P1 generated by counteracting the TOPSAR;

[0034] Figure 7b It is a cross-sectional view of the false target point P2 generated by counteracting the TOPSAR;

[0035] Figure 7c It is a cross-sectional view of the false target point P3 generated by counteracting the TOPSAR;

[0036] Figure 8 It is an imaging diagram of the real scene echo;

[0037] Figure 9 It is an imaging diagram of the false scene generated by the sliding spotlight SAR deception jamming;

[0038] Figure 10 It is an imaging diagram of the false scene generated by the TOPSAR deception jamming;

[0039] Figure 11 It is a flow chart of the general multi-mode SAR large scene deception jamming generation method of the present invention. Detailed implementation manners

[0040] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0041] As Figure 11 shown, the general multi-mode SAR large scene deception jamming generation method of the present invention includes the following steps:

[0042] Step 1, use the jammer to intercept the platform, antenna and signal parameters of the SAR radar entering the detection range, and select the SAR image template with complex backscattering coefficient according to the interference target requirements;

[0043] Step 2: In the azimuth time-frequency transformation domain, introduce a frequency modulation term and a window function related to the sliding factor and the Doppler center change slope, and modulate the azimuth time-domain position of each scatterer in the SAR image template onto the support domain function of the azimuth spectrum, forming the corresponding changed Doppler center azimuth support domain for each mode;

[0044] Step 3: In the two-dimensional frequency domain, use the strip SAR azimuth frequency domain deception jamming algorithm to construct cross-coupling terms and generate the false scene-related frequency response function for each mode;

[0045] Step 4: Use the conjugate function of the azimuth dechirp function to restore the Doppler history of the false scene-related frequency response function and complete the azimuth spectrum aliasing processing;

[0046] Step 5: Multiply the jammer-related frequency response function by the false scene-related frequency response function to obtain the multi-mode SAR jamming frequency response function, and generate the deception jamming signal by pulse-by-pulse modulation through a digital radio frequency memory.

[0047] The present invention will be further explained below with reference to the accompanying drawings. The deception jamming geometric model of each mode of SAR is drawn, and the moving geometric model of the sliding spotlight SAR in the slant range plane is shown as Figure 1 shown. Figure 1 In , the is the slant range direction axis, and the is defined as the shortest slant range from the SAR flight track to the beam aiming point, and the is the shortest slant range from the SAR flight track to the mapping strip. Define the sliding coefficient as . During the mapping period of length by the SAR, the distance flown by the SAR platform is , which also represents the flight distance during the SAR data acquisition time. is the angular velocity of the rotation of the radar center beam pointing. The sliding spotlight SAR radar scan starts from the starting illumination beam in the figure, and during the entire scan process, the radar beam pointing rotates to the position of the termination illumination beam at an angular velocity of . Generally, the beam scan speed of the sliding spotlight SAR is lower than the platform speed. Define as the scan speed of the radar beam on the ground, and as the flight speed of the SAR platform. Then the observed length of the beam scan on the ground is , where is the coverage width of the radar beam projection on the ground. The blue grid area is the large scene deception jamming area, which coincides with the sliding spotlight SAR observation area. Assume that is an arbitrary point in the deception jamming area, and is the instantaneous slant angle of point is the beam width of the SAR.

[0048] As Figure 2 shown, the beam aiming point of TOPSAR is located above the SAR platform. is the shortest slant range from the TOPSAR flight track to the beam aiming point, and the sliding coefficient . The TOPSAR radar scan starts from the initial illumination beam in the figure. During the entire scan process, the radar beam direction rotates to the position of the termination illumination beam at an angular velocity of . The rotation direction of the TOPSAR beam direction is opposite to that of the sliding spotlight SAR. Therefore, the scanning speed of the radar beam on the ground is higher than the platform speed, so that when the SAR observes the same azimuth swath length , TOPSAR only needs a shorter flight distance . Figure 2 The dark gray solid line area in the figure is the TOPSAR azimuth observation area, and the blue grid area is the large scene deception interference area.

[0049] Specifically, the step 1 includes:

[0050] Step 1.1: Set the SAR parameters detected during the jammer reception phase, mainly including SAR platform parameters, SAR antenna parameters, and SAR signal parameters. In addition, it is also necessary to identify the SAR working mode. Usually, for the convenience of imaging processing, various working modes of the SAR system often need to ensure parameter stability to guarantee system operation, and before locking the interfering target SAR, the radar reception and detection system has often conducted a preliminary analysis of various parameters of the SAR.

[0051] Step 1.2: According to the interference target requirements, select the SAR image template with the complex backscattering coefficient as follows:

[0052] ;

[0053] where is the azimuth coordinate of the point target in the SAR image, is the range coordinate. m and n represent the serial numbers of the point target in the azimuth and range directions, is the Dirac function, , respectively represent the sampling intervals of the pre-interference area in the azimuth and range directions, is the summation symbol.

[0054] Specifically, the step 2 includes:

[0055] Step 2.1, perform azimuth Fourier transform on the deception interference template to convert the SAR image template with range-azimuth position information to the azimuth frequency domain. In order to retain the azimuth time-domain position information of point targets in the spectrum, an azimuth quadratic frequency modulation term related to and is introduced in the azimuth frequency domain :

[0056] ;

[0057] wherein, is the imaginary unit, is the azimuth frequency axis, is the range axis in the range direction, is the flight speed of the SAR platform, and exp represents the exponential function.

[0058] Step 2.2, perform inverse azimuth Fourier transform on the azimuth frequency-modulated deception interference template, and add the azimuth beam illumination window of each point of the false scene in the azimuth time domain , to obtain the deception interference template with the time-varying azimuth beam illumination window added :

[0059] ;

[0060] wherein, is the synthetic aperture length, is the azimuth time axis.

[0061] Step 2.3, perform azimuth Fourier transform on the deception interference template with the time-varying azimuth beam illumination window added, and then remove the azimuth quadratic frequency modulation term related to and , and equivalently construct the azimuth support domain function with a varying Doppler center through time-frequency transformation :

[0062] ;

[0063] wherein, is the effective Doppler bandwidth.

[0064] Specifically, the said step 3 includes:

[0065] In the two-dimensional frequency domain, use the strip SAR azimuth frequency domain deception interference algorithm to construct cross-coupling terms to form the false scene-related frequency response functions of each mode as:

[0066] ;

[0067] wherein, is the wavelength, is the range frequency window, is the azimuth frequency window, is the range frequency axis, is the center frequency of the SAR signal, is the signal bandwidth. There are already many existing strip SAR azimuth frequency domain deception jamming methods. These methods have different emphases on modulation efficiency and modulation accuracy and can directly generate the frequency response function related to the false scene.

[0068] Specifically, step 4 includes:

[0069] Step 4.1, first convert the frequency response function to the azimuth frequency domain. By relying on the azimuth dechirp function to remove the azimuth-variant Doppler center frequency, and convert the azimuth time-domain false scene-related frequency response function with azimuth-variance into the false scene-related frequency response function without azimuth-variance :

[0070] ;

[0071] wherein, is the azimuth Fourier transform.

[0072] After azimuth dechirping, the Doppler bandwidth of the false scene-related frequency response function is consistent with the effective Doppler bandwidth , and the variance of the Doppler center frequency is removed. On this basis, the PRF (Pulse Repetition Frequency) of the interference can be reset.

[0073] Step 4.2, complete signal downsampling by uniformly filtering and sampling the azimuth effective signal, and reduce the sampling rate to be consistent with the pulse repetition frequency of the SAR system;

[0074] Step 4.3, use the conjugate function of the azimuth dechirp function to restore the Doppler history of the false scene-related frequency response function, complete the azimuth spectrum aliasing processing, and obtain the false scene-related frequency response function :

[0075] ;

[0076] wherein, is the inverse azimuth Fourier transform.

[0077] Specifically, step 5 includes:

[0078] Step 5.1, the jammer-related frequency response function Frequency response function related to false scene is multiplied to obtain the interference frequency response function .

[0079] ;

[0080] wherein is the target point to the slant range of the SAR, is the jammer to the slant range of the SAR.

[0081] Step 5.2, the intercepted SAR signal is subjected to a frequency-domain convolution operation with the non-linear trajectory SAR interference frequency response function to obtain the retransmitted interference signal :

[0082] ;

[0083] wherein is the inverse Fourier transform in the range direction, is the Fourier transform in the range direction. is the one-way SAR signal intercepted and stored by the receiver.

[0084] As Figure 3 shown, the present invention also provides a general multi-mode SAR large scene deception interference generation device, including the following modules:

[0085] Deception interference template generation module, which uses the platform, antenna and signal parameters of the SAR radar detected by the jammer, and selects the SAR image template with complex backscattering coefficient according to the interference target requirements;

[0086] Beam pointing control module, in the azimuth time-frequency transformation domain, introduces the frequency modulation term and window function related to the sliding factor and the Doppler center change slope, and modulates the azimuth time-domain position of each scatter point in the SAR image template to the support domain function of the azimuth spectrum, forming the corresponding variable Doppler center azimuth support domain for each mode;

[0087] Cross-coupling term unified construction module, in the two-dimensional frequency domain, constructs the cross-coupling term by using the strip SAR azimuth frequency domain deception interference algorithm to generate the false scene related frequency response function of each mode;

[0088] Azimuth aliasing construction module, in the azimuth frequency domain, downsamples the false scene related frequency response function of high pulse repetition frequency by dechirping method to complete the azimuth spectrum aliasing processing;

[0089] The deception jamming real-time generation module multiplies the frequency response function related to the jammer by the frequency response function related to the false scene to obtain the multi-mode SAR jamming frequency response function, and generates the deception jamming signal by pulse-by-pulse modulation through a digital radio frequency memory.

[0090] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, the steps of the above-mentioned general multi-mode SAR large-scene deception jamming generation method are implemented.

[0091] The present invention also provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the above-mentioned general multi-mode SAR large-scene deception jamming generation method are implemented.

[0092] To verify the effectiveness of the present invention, simulations were carried out. Assume that the SAR radar parameters are as shown in Table 1.

[0093] Table 1

[0094] The slant ranges of the beam aiming points of the sliding spotlight SAR and TOPSAR are respectively set to and , representing that the azimuth resolution of the sliding spotlight SAR is , and the azimuth resolution of the TOPSAR is . First, false point target deception jamming is carried out on the multi-mode SAR, and index analysis is carried out on the jammed imaging point targets to verify the deception jamming accuracy and effectiveness of the proposed algorithm. Different false point target jamming templates are set according to the characteristics of each mode of SAR. The deception jammer is set at the center of the mapping strip scene, located at the position. For the sliding spotlight SAR, the set positions are , , false point targets. For the TOPSAR, the set positions are , , false point targets. According to the multi-mode SAR unified large-scene deception jamming construction process shown in Figure 3 , false point target jamming templates are input to generate the deception jamming signals of each mode of SAR respectively, and then index analysis of the imaging point targets is carried out. Figure 4 and Figure 5 are respectively the enlarged imaging diagrams of the false point targets of each mode. It can be found that the false point targets of each mode of SAR are well focused in both the range direction and the azimuth direction, and the ratio of the IRW in the range direction and the azimuth direction is also almost consistent with the simulation settings.

[0095] To accurately analyze the deception jamming quality of the proposed algorithm, cross-sectional views of point targets in the range direction and azimuth direction of each mode SAR are plotted for comparative analysis. The comparison of point target cross-sectional views is as Figure 6a , Figure 6b , Figure 6c and Figure 7a , Figure 7b , Figure 7c shown. The index analysis includes the 3dB impulse response width (IRW), peak sidelobe ratio (PSLR), and integrated sidelobe ratio (ISLR), as shown in Table 2 (Index Analysis Table). The results of the simulation experiments show that the cross-sectional profiles of the false targets generated by the multi-mode SAR unified large-scene deception jamming algorithm almost coincide with the original echo point targets, and the azimuth accumulation time of the false targets in the deception jamming signal can be adjusted through the beam scanning support domain construction module.

[0096] Table 2

[0097] In the second group of simulation experiments, the multi-mode SAR deception jamming algorithm proposed in the present invention is used to generate a false scene to protect high-value targets. The forest scene is selected as the interference template for the false scene, and the intercepted signals of the sliding spotlight SAR and TOPSAR are respectively completed for deception jamming modulation. Finally, the deception jamming signal of the false scene is mixed with the original echo signal of the multi-mode SAR for imaging. The original background imaging is as Figure 8 shown, and the false scene deception jamming imaging of the sliding spotlight SAR and TOPSAR is as Figure 9 and Figure 10 shown. The high-value targets within the dashed box are covered by the forest false scene, and the texture fidelity of the false forest scene is extremely high, which can be well integrated into the background ground object scene. The results of the simulation experiments further prove the effectiveness and multi-mode adaptability of the algorithm.

[0098] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of the present invention can be implemented in various computer languages. For example, object-oriented programming languages such as Java and interpreted scripting languages such as JavaScript.

[0099] The present invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It should be understood that each flow and / or block of the flowchart illustrations and / or block diagrams, and combinations of flows and / or blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions executed by the processor of the computer or other programmable data processing apparatus create means for implementing the functions specified in the flowchart Figure 1 for one or more flows and / or blocks Figure 1 for one or more blocks.

[0100] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means that implement the functions specified in the flowchart Figure 1 for one or more flows and / or blocks Figure 1 for one or more blocks.

[0101] These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, so that the instructions executed on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart Figure 1 for one or more flows and / or blocks Figure 1 for one or more blocks.

[0102] Although the preferred embodiments of the present invention have been described, additional changes and modifications can be made by those skilled in the art once they learn of the basic inventive concept. Therefore, the appended claims are intended to be construed to include the preferred embodiments as well as all changes and modifications that fall within the scope of the present invention.

[0103] It is apparent that those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these modifications and variations.

Claims

1. A general multi-mode SAR large-scene deception jamming generation method, characterized in that, It includes the following steps: Step 1: Use an interferer to intercept the platform, antenna, and signal parameters of the SAR radar entering the detection range, and select a SAR image template with complex backscattering coefficients according to the interference target requirements; Step 2: In the azimuth time-frequency transformation domain, introduce a frequency modulation term and a window function related to the sliding factor and the Doppler center change slope, and modulate the azimuth time-domain positions of the scattering points in the SAR image template onto the support domain function of the azimuth spectrum to form a variable Doppler center azimuth support domain corresponding to each mode; Step 3: In the two-dimensional frequency domain, use the strip SAR azimuth frequency-domain deception interference algorithm to construct cross-coupling terms and generate a false scene-related frequency response function for each mode; Step 4: Use the conjugate function of the azimuth dechirp function to restore the Doppler history of the false scene-related frequency response function and complete the azimuth spectrum aliasing processing; Step 5: Multiply the interferer-related frequency response function by the false scene-related frequency response function to obtain a multi-mode SAR interference frequency response function, and generate a deception interference signal through pulse-by-pulse modulation by a digital radio frequency memory.

2. The general multi-mode SAR large-scene deception jamming generation method according to claim 1, wherein In the said Step 1, the SAR parameters in the interferer interception stage are used to identify the SAR operating mode.

3. The general multi-mode SAR large-scene deception jamming generation method according to claim 2, wherein In step 1, according to the interference target requirements, select an SAR image template with a complex backscattering coefficient : ​ ； Among them, is the azimuth coordinate of the point target in the SAR image, is the range coordinate; m and n represent the serial numbers of the point target in the azimuth and range directions, is the Dirac function, and represent the sampling intervals of the pre-interference region in the azimuth and range directions respectively, is the summation symbol.

4. The general multi-mode SAR large-scene deception jamming generation method according to claim 3, wherein The said Step 2 includes: Step 2.1, perform azimuth Fourier transform on the deception interference template to transform the SAR image template with range-azimuth position information into the azimuth frequency domain; introduce an azimuth quadratic chirp term related to the sliding factor and the Doppler center change slope ; Step 2.2, perform azimuth inverse Fourier transform on the spoofing interference template after azimuth Fourier transform, and add the azimuth beam illumination window of each point of the false scene in the azimuth time domain , to obtain a spoofing interference template with a time-varying azimuth beam illumination window ; Step 2.3, perform azimuth Fourier transform on the deception interference template with the time-varying azimuth beam illumination window, and then remove the azimuth quadratic frequency modulation terms related to and , and equivalently construct the azimuth support domain function with a varying Doppler center through time-frequency transformation .

5. The general multi-mode SAR large-scene deception jamming generation method according to claim 4, characterized in that The said Step 3 includes: In the two-dimensional frequency domain, the cross-coupling terms are constructed by using the azimuth frequency domain deception interference algorithm of strip SAR to form the false scene related frequency response functions of each mode. It is: ； Among them, is the wavelength, is the range frequency window, is the azimuth frequency window, is the range frequency axis, is the center frequency of the SAR signal, is the signal bandwidth; There are already many existing strip SAR azimuth frequency domain deception jamming methods, and these methods have their own emphases in modulation efficiency and modulation accuracy, and can directly generate the frequency response function related to the false scene.

6. The general multi-mode SAR large-scene deception jamming generation method according to claim 5, wherein The said Step 4 includes: Step 4.1, convert the frequency response function to the azimuth frequency domain, and remove the azimuth-variant Doppler center frequency through the azimuth dechirp function with the Doppler center change slope , so that the azimuth time-domain false scene-related frequency response function with azimuth-variance becomes the false scene-related frequency response function without azimuth-variance ; After azimuth de-skewing, based on the fact that the Doppler bandwidth of the false scene related frequency response function is consistent with the effective Doppler bandwidth and the spatial variability of the Doppler center frequency is removed, reset the pulse repetition frequency of the interference; ​ Step 4.2: Uniformly filter and sample the azimuth effective signal to complete signal downsampling and reduce the sampling rate to be consistent with the pulse repetition frequency of the SAR system; Step 4.3, using the azimuth de-aliasing function and its conjugate function to restore the Doppler history of the false scene-related frequency response function, complete the azimuth spectrum aliasing processing, and obtain the false scene-related frequency response function in the azimuth time domain after correcting the pulse repetition frequency .

7. The general multi-mode SAR large-scene deception jamming generation method according to claim 6, characterized in that, The said Step 5 includes: Step 5.1, multiply the frequency response function related to the jammer with the frequency response function related to the false scenario to obtain the interference frequency response function ; Step 5.2, the intercepted SAR signal is subjected to a frequency-domain convolution operation with the non-linear track SAR interference frequency response function to obtain the repeater interference signal .

8. A general multi-mode SAR large-scene deception jamming generation device, characterized in that, It includes the following modules: A deception interference template generation module, which uses an interferer to intercept the platform, antenna, and signal parameters of the SAR radar entering the detection range, and selects a SAR image template with complex backscattering coefficients according to the interference target requirements; A beam pointing control module, which in the azimuth time-frequency transformation domain, introduces a frequency modulation term and a window function related to the sliding factor and the Doppler center change slope, and modulates the azimuth time-domain positions of the scattering points in the SAR image template onto the support domain function of the azimuth spectrum to form a variable Doppler center azimuth support domain corresponding to each mode; A cross-coupling term unified construction module, which in the two-dimensional frequency domain, uses the strip SAR azimuth frequency-domain deception interference algorithm to construct cross-coupling terms and generate a false scene-related frequency response function for each mode; An azimuth aliasing construction module, which uses the conjugate function of the azimuth dechirp function to restore the Doppler history of the false scene-related frequency response function and complete the azimuth spectrum aliasing processing; A deception interference real-time generation module, which multiplies the interferer-related frequency response function by the false scene-related frequency response function to obtain a multi-mode SAR interference frequency response function, and generates a deception interference signal through pulse-by-pulse modulation by a digital radio frequency memory.

9. An electronic device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, When the said processor executes the said program, it realizes the steps of a general multi-mode SAR large-scene deception interference generation method as described in any one of claims 1-7.

10. A non-transitory computer-readable storage medium storing a computer program thereon, characterized in that, When the said computer program is executed by a processor, it realizes the steps of a general multi-mode SAR large-scene deception interference generation method as described in any one of claims 1-7.

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