A method and device for SAR time-domain high-fidelity moving target single-base deception jamming

Abstract

This invention provides a method and apparatus for high-fidelity single-base deception jamming of SAR moving targets in the time domain, belonging to the field of radar countermeasures technology. The method includes: acquiring signal parameters of signals transmitted by a SAR platform and generating an initial signal with an additional two-dimensional time-domain coupled modulation phase; determining the center position of a group of false targets, designing a jamming area position control template, multiplying it with the initial signal to control the position of the jamming area; designing a multi-target rapid generation template based on the initial position coordinates of the false moving targets, multiplying it with the multiplied signal to generate multiple false moving target signals with the same speed; classifying and designing parallel computation of the two-dimensional time-domain coupled modulation phase and the multi-target rapid generation template for false moving targets with different speeds to obtain the final jamming signal; and performing digital-to-analog conversion and up-conversion processing on the final jamming signal, forwarding it pulse-by-pulse to the target SAR system. This invention enables a single jammer to generate multiple high-fidelity false moving targets with different motion states.

Description

Technical Field

[0001] This invention belongs to the field of radar countermeasures technology, specifically relating to a method and apparatus for high-fidelity SAR time-domain moving target single-base deception jamming. Background Technology

[0002] Synthetic Aperture Radar (SAR) is a microwave detection device used for Earth observation, possessing all-weather, high-resolution imaging capabilities and widely applied in topographic mapping, resource exploration, and other fields. SARs equipped with Ground Moving Target Indication (GMTI) capabilities can quickly detect, track, and distinguish different types of moving targets, posing a threat to the security of key protected targets. Therefore, researching electronic jamming techniques targeting SAR-GMTI has become an important topic in the field of electronic warfare. Based on different jamming methods, SAR-GMTI jamming methods can be divided into two categories: active jamming and passive jamming.

[0003] While existing single-base deception jamming methods can generate relatively realistic moving targets at specific speeds, their universality has not been proven. Multi-base deception jamming methods face challenges in engineering implementation. Obtaining the channel spacing of multi-channel SAR through parameter reconnaissance is difficult, as is strictly controlling the spacing between multiple jammers and achieving signal-level coordinated jamming. Furthermore, the algorithms are highly complex and have low robustness to reconnaissance parameter errors. For example, Chinese patent application CN202211716066.1 (A method for jamming multiple false targets in SAR-GMTI) suffers from problems such as large differences between false and real targets and insufficient universality in experimental simulations. Chinese patent application CN202410969993.7 (A multi-channel SAR-GMTI deception jamming method, system, storage device, and electronic device based on multi-jammer motion modulation) is difficult to implement in engineering and has low robustness. Therefore, developing a multi-area jamming method using a single jammer is of great significance. Chinese patent application CN202510490117.0 (A Single-Based Multi-Domain Jamming Method and Apparatus for SAR-GMTI) simulates the phase of a moving target only in the azimuth-time relation, simulating only the azimuth-time correlated phase of the moving target while ignoring the influence of the range-time phase modulation of the moving target. This leads to errors in the position offset caused by the range velocity of false moving targets, resulting in differences from those of real moving targets at the same velocity. Summary of the Invention

[0004] To address the shortcomings of existing SAR-GMTI deception jamming methods, this invention provides a SAR time-domain high-fidelity single-base deception jamming method and apparatus for moving targets. It combines a basic jamming signal with two-dimensionally coupled range-time and azimuth-time modulation phase. Then, using a jamming area position control template and a multi-target rapid generation template, it can accurately generate multiple deception targets based on the required number and speed of moving targets to be protected, thus masking real targets in the scene in the two-dimensional time domain. The position offset and azimuth defocus of the generated false moving targets were compared with those of the real moving targets, theoretically and through simulation experiments, demonstrating the universality and effectiveness of this invention in generating high-fidelity false moving targets in the two-dimensional time domain. This invention requires only one jammer to operate, has low algorithm complexity, and is easier to implement in engineering.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A high-fidelity SAR time-domain motion target single-base deception jamming method includes the following steps:

[0007] Step 1: Obtain the signal parameters of the signal transmitted by the SAR platform and generate an initial signal with an additional two-dimensional time-domain coupled modulation phase;

[0008] Step 2: Determine the center position of the false target group, design the interference area position control template, multiply it with the initial signal to obtain the multiplied signal, and control the position of the interference area.

[0009] Step 3: Design a multi-target rapid generation template based on the initial position coordinates of the false moving targets, and multiply it with the signal obtained from step 2 to generate multiple false moving target signals with the same velocity.

[0010] Step 4: For false moving targets at different speeds, design parallel computation two-dimensional time-domain coupled modulation phase and multi-target fast generation templates, and superimpose multiple sets of interference signals to obtain the final interference signal;

[0011] Step 5: Perform digital-to-analog conversion and up-conversion processing on the final jamming signal, and forward it to the target SAR system pulse by pulse, so that a single jammer can generate multiple highly realistic false moving targets with different motion states.

[0012] The present invention also provides a SAR time-domain high-fidelity moving target single-base deception jamming device, comprising:

[0013] The signal reception module is used to detect and receive signals transmitted by the target SAR system.

[0014] The downconversion module is used to perform downconversion processing on the received SAR signal;

[0015] The analog-to-digital converter module is used to convert the intercepted target SAR transmitted signals into digital signals.

[0016] The signal parameter measurement module is used to measure signal parameters such as pulse width, bandwidth, and pulse repetition frequency of the received signal.

[0017] A two-dimensional time-domain coupled phase modulation module is used to add the phase characteristics of a real moving target to the intercepted signal in order to simulate the same position offset effect and similar energy broadening effect as a real moving target;

[0018] The jamming area position control module is used to control the position of the entire area covered by the jammer;

[0019] The multi-target rapid generation module is used to control the different positions of the same type of moving targets in the scene;

[0020] The parallel processing and superposition module for interference signals is used to generate false moving target groups with different motion states and reduce the time for generating interference signals.

[0021] The digital-to-analog converter module converts the acquired digital interference signal into an analog signal;

[0022] The upconversion module is used for upconversion processing of analog interference signals;

[0023] The transmitting module is used to transmit interference signals pulse by pulse.

[0024] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of the above-described SAR time-domain high-fidelity moving target single-base deception jamming method.

[0025] The present invention also provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the above-described SAR time-domain high-fidelity moving target single-base deception jamming method.

[0026] Beneficial effects:

[0027] This invention employs a unique method to achieve interference effects: first, two-dimensional time-domain coupling phase compensation is added to the transmitted interference signal; then, it undergoes modulation processing sequentially through an interference area position control module, a multi-target rapid generation module, and an interference signal parallel computation and superposition module. With this technology, only one jammer is needed to rapidly generate multiple groups of false moving targets with varying motion states. These false targets are highly similar to real moving targets in the two-dimensional time domain, exhibiting extremely high fidelity. Compared to multi-jammer joint deception jamming, this invention does not require consideration of signal coordination and positional layout among multiple jammers, making engineering implementation much simpler. Compared to traditional single-jammer phase compensation methods, the phase compensation term in this invention involves not only azimuth time but also range time. After phase compensation, the phase of the interference signal perfectly matches the phase of the echo from a real moving target with the same motion state and position, thus achieving a highly realistic deception jamming effect against the velocities of various common ground moving targets in the two-dimensional time domain. Attached Figure Description

[0028] Figure 1 This is a flowchart of a SAR time-domain high-fidelity moving target single-base deception jamming method according to the present invention;

[0029] Figure 2 This is a typical SAR-GMTI deception and jamming scenario diagram;

[0030] Figure 3 It is a spatial map of the echo range of four real moving targets after compression;

[0031] Figure 4 This is a compressed spatial map showing the echo range of four spurious moving targets.

[0032] Figure 5 This is a spatial map of four real moving targets after echo BP imaging;

[0033] Figure 6 This is a spatial map of the echo backpropagation of four false moving targets;

[0034] Figure 7 It is a spatial map after echo refocusing imaging of four real moving targets;

[0035] Figure 8 This is a spatial map after echo refocusing imaging of four false moving targets;

[0036] Figure 9 This is a schematic diagram illustrating the framework of a SAR time-domain high-fidelity moving target single-base deception jamming device according to the present invention. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this invention clearer, the 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 merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0038] like Figure 1 As shown, this invention discloses a SAR time-domain high-fidelity single-base deception jamming method for moving targets. It is a synthetic aperture radar jamming signal generation method based on two-dimensional time-domain coupled modulation phase and rapid multi-target template generation. This method is used to rapidly generate multiple two-dimensional time-domain high-fidelity false moving target groups with different motion states for deception jamming, thereby confusing three-channel SAR-GMTI moving target detection in the two-dimensional time domain. The method includes the following steps:

[0039] Step 1: The jammer intercepts signals transmitted from the SAR platform, performs down-conversion and digital-to-analog conversion on the received SAR signals, stores the intercepted SAR signals in a digital radio frequency memory (DRFM), and measures parameters (carrier frequency, frequency modulation, azimuth sampling rate, etc.). Based on preliminary reconnaissance, the distance and altitude from the SAR platform to the jammer are obtained. Using these parameters, an initial signal with a two-dimensional time-domain coupled modulation phase is generated in the DRFM, and the signal is then subjected to a range-to-Fourier transform to obtain range-frequency and azimuth-time domain signals.

[0040] Step 2: Design system functions in the range frequency domain and azimuth time domain based on the center position of the false target group to be generated, multiply them with the signal from Step 1, and then perform range-to-Fourier inverse transform to obtain a two-dimensional time domain signal.

[0041] Step 3: Calculate the two-dimensional time-domain multi-target rapid generation template based on the initial position coordinates of the expected multiple false moving targets, and multiply it with the signal from Step 2. Then, perform a range-to-Fourier transform to obtain range-frequency and azimuth-time domain signals.

[0042] Step 4: For false moving targets at different speeds, a classification design is adopted, and parallel operation is performed. The above three steps are repeated, and then multiple sets of interference signals are superimposed to obtain the final interference signal.

[0043] Step 5: Perform digital-to-analog conversion and up-conversion processing on the interference signal from Step 4, and forward the up-converted interference signal pulse by pulse to the target three-channel SAR-GMTI system (target SAR system).

[0044] In such Figure 2In a classic three-channel SAR-GMTI jamming scenario, assuming the SAR platform's flight direction is along the x-axis, the direction perpendicular to the flight path is along the y-axis, and the direction perpendicular to the ground upwards is the z-axis, the flight altitude is expressed as... The mapping band (i.e., mapping width) along the range direction of the SAR signal beam is as follows: Figure 2 As shown. The velocity of the SAR platform is expressed as... The SAR beam direction is the frontal side-looking direction, and the jammer's position is set to... .exist Figure 2 The three channels of the SAR platform are labeled 0, 1, and 2. Channel 1 transmits a linear frequency modulated (LFM) signal, and the echo signals are received by channels 0, 1, and 2 respectively. The real-time slant range in the azimuth direction from the jammer to channel 1 of the SAR platform is set to... The instantaneous slant range at time 0 in the azimuth direction is The pulse repetition frequency is expressed as... The signal carrier frequency is represented as The distance between adjacent channels is expressed as... , Need to meet , Represents any positive integer. In the scenario, it is assumed that multiple false moving point targets (i.e., false targets in the following text) are to be generated, and are labeled as... , , , ..., The velocities of these false targets are respectively expressed as... .exist Figure 2 Three targets are used to illustrate this. The interference scenario (i.e.) Figure 2 The center point of the interference area is marked as .

[0045] Specifically, step one includes:

[0046] The baseband echo signal from the jammer's location on channel 1. It can be represented as:

[0047] (1)

[0048] in, For distance to time, For direction and time, Represents the distance-to-window function. This is the azimuth window function. Represents the speed of light. Represents the duration of the signal. The carrier frequency representing the signal. This represents the modulation frequency of a linear frequency modulated signal. The real-time slant distance from the stationary target at the location of the jammer to channel 1 is represented by j, which represents the imaginary unit, and exp() represents the exponential function. .

[0049] Under low slant angle conditions, the real-time slant range from a stationary point target at the jammer's location to channel 1 can be approximated as a polynomial using Taylor expansion, expressed as:

[0050] (2)

[0051] in, , representing the slant distance from channel 1 to the jammer at time 0 in the azimuth direction.

[0052] if Let represent a real moving point target at the location of the jammer, where Represents speed, Represents acceleration. In At any given time, the slant distance from the target to channel 1 is expressed as... The calculation is as follows:

[0053] (3)

[0054] By using Taylor expansion and retaining the first three terms, the expression of (3) can be restated as:

[0055] (4)

[0056] Combining equations (1) and (4), the echo signal from the real moving target to the receiving channel 1 is... It can be represented as:

[0057] (5)

[0058] Comparing Equation (1) and Equation (5), we can consider adding a compensated phase to the jammer signal to simulate the phase from a real moving target.

[0059] and Differences between Represented as:

[0060] (6)

[0061] Equation (6) can be simplified to:

[0062] (7)

[0063] Among them, coefficient Represented as:

[0064] (8)

[0065] (9)

[0066] in, Indicates the wavelength of the received signal.

[0067] for and Set intermediate parameters intermediate parameters Let the difference According to equation (5), ignoring the window function and amplitude, the echo signal from the real moving target to the receiving channel 1 is... Represented as:

[0068] (10)

[0069] in, The second item requiring compensation is represented as:

[0070] (11)

[0071] Therefore, the second phase that needs compensation Represented as:

[0072] (12)

[0073] Combining equations (7) and (12), the total phase terms requiring compensation can be divided into two parts. One part consists of terms coupled with the range-time and azimuth-time axes. The other part consists of items that are only related to the direction of time. , represented as:

[0074] (13)

[0075] (14)

[0076] In equations (13) and (14), Let be a variable, for each azimuth time, It is a fixed array. The other quantities in equations (13) and (14) are constants, all of which can be obtained through preliminary reconnaissance, signal reception, and interception. Additionally, in equation (14)... The rate of change and the order of magnitude of the cubic and quartic terms are much smaller than those of the first two terms, and can be ignored in most cases.

[0077] Therefore, the echo of the interference signal to channel 1 It can be represented as:

[0078] (15)

[0079] In range-Doppler (RD) imaging algorithms, after range migration correction, azimuth-matched filtering can be solved from temporal convolution when performing azimuth compression. This is followed by slow-time stretching after azimuth compression. It can be calculated and expressed as:

[0080] (16)

[0081] in, This is expressed as the time length of a synthetic aperture and the azimuth modulation frequency. The calculation is as follows:

[0082] (17)

[0083] Therefore, energy broadening in the azimuth direction for false moving targets in SAR images Represented as:

[0084] (18)

[0085] It can be observed that its azimuth energy broadening is consistent with the theoretical value of a real moving target at the same speed.

[0086] Through terms coupled with distance-time and azimuth-time Items that are only related to location and time The Doppler center shift of the false moving target is consistent with that of the real moving target at the same speed and position. The azimuth position shift of the false moving target... It can be calculated as follows:

[0087] (19)

[0088] Its azimuth offset is consistent with that of a real moving target at the same position and speed in theoretical calculations.

[0089] The above analysis shows that when velocity and acceleration are the same, the orientation shift and energy broadening of the dummy moving target are related to its position. The actual moving target is consistent with the real moving target. However, since the jammer is static, the synthetic aperture length of the real moving target and the false moving target may not be consistent.

[0090] Therefore, the initial jamming signal emitted by the jammer has two additional phase compensations. It can be represented as:

[0091] (20)

[0092] The window functions in both directions used Represented by a rectangular window function. This indicates the pulse duration of a single pulse signal.

[0093] Specifically, step two includes:

[0094] From the jammer to the jamming signal echo received from channel 1 The expression is:

[0095] (twenty one)

[0096] in, This represents the convolution operation and the real-time slant distance from the jammer to channel 1. Represented as:

[0097] (twenty two)

[0098] From the center of the interference scene to receiving the echo from channel 1 Represented as:

[0099] (twenty three)

[0100] in, Indicates in The backscattering coefficient at the location, and the real-time slant distance from the center of the interference scene to channel 1. Represented as:

[0101] (twenty four)

[0102] To generate moving point targets The system functions of the jammer The following equation should be satisfied:

[0103] (25)

[0104] in, for Interference signal echoes from false moving targets at the location.

[0105] Among them, the interference area location control template Represented as:

[0106] (26)

[0107] Among them, the difference between the real-time slant range from the center of the interference scenario to channel 1 and the real-time slant range from the jammer to channel 1. The calculation is as follows:

[0108] (27)

[0109] Interference signals can be rapidly generated by multiplying them in the range-direction frequency domain with the location control template of the interference region. In the range-direction frequency domain expression for:

[0110] (28)

[0111] By combining equations (25) and (28), in Interference signal echo of false moving target at the location It can be represented as:

[0112] (29)

[0113] in This represents the distance to the Fast Fourier Transform. The symbol represents the inverse fast Fourier transform of distance, and the dot symbol represents the product operation.

[0114] Specifically, step three includes:

[0115] The location of the interfering sub-region is controlled using a two-dimensional frequency shift method. If the range-direction frequency shift of the signal is... The azimuth frequency shift is Then there is no signal with additional motion modulation phase. The expression is:

[0116] (30)

[0117] The expression after imaging using the RD algorithm is:

[0118] (31)

[0119] in, Indicates the Doppler center frequency shift, This represents the signal amplitude after two-dimensional compression.

[0120] The expression shows that the result will produce a positional shift in the imaging result, corresponding to the range-direction positional shift. for:

[0121] (32)

[0122] Azimuth position offset for:

[0123] (33)

[0124] in, (34)

[0125] When different locations are generated in the scene When there are multiple false moving targets, the frequency shift corresponding to the initial position coordinates of each false moving target point is represented as:

[0126] (35)

[0127] make This represents a template for rapid generation of multiple objectives. express The discrete Fourier transform has:

[0128] (36)

[0129] Where i represents the target sequence number.

[0130] Then add the signal after the multi-target fast template generation. The expression can be used Represented as:

[0131] (37)

[0132] Since the system response of SAR imaging is only related to the time term and Correlation allows for the separation of terms related to frequency shift, thus improving imaging results. for:

[0133] (38)

[0134] in, This indicates that an imaging operation is performed on the echo data.

[0135] Therefore, a multi-target rapid generation template can be designed based on the positions of the multiple illusory moving target points to be generated. This is then multiplied by the signal. The signal is then used to quickly generate a template through a multi-target algorithm. The modulation can generate multiple false moving target points with the same motion state. Combining the final equation (20) of step one, the two-dimensional time-domain signal generated in step two... Represented as:

[0136] (39)

[0137] pass The jammer can generate signals of multiple false moving point targets with the same motion state.

[0138] Specifically, step four includes:

[0139] To generate multiple target groups with different motion states, targets with the same motion state can be grouped into one category, and targets with different motion states into different categories. For each target group with different motion states, a separate two-dimensional time-domain coupled modulation phase and a fast multi-target generation template are designed. Parallel computation followed by signal accumulation is used to obtain the final expression of the interference signal. Assuming that after classification, the scene contains... A group of false moving targets in different motion states will ultimately interfere with the transmitted signal. Represented as:

[0140] (40)

[0141] in, This represents the q-th type of interference signal after phase compensation corresponding to the motion state. This represents the control function for the center position of the q-th target group. This represents the location template for each target within the q-th target group.

[0142] By superimposing multiple sets of false moving target interference signals with different motion states in step four, multiple groups of false moving targets with different motion states can be quickly generated in the scene.

[0143] Specifically, step five includes:

[0144] A digital-to-analog converter (DAC) is used to convert the range- and azimuth-modulated digital jamming signal into an analog jamming signal. The jammer then performs up-conversion processing and forwards the signal pulse-by-pulse to the SAR-GMTI (Target SAR) system. After down-conversion, analog-to-digital conversion, and imaging processing by the target SAR system, the analog jamming signal generates multiple highly realistic false moving targets on the SAR image. After DPCA cancellation, the false moving targets can be detected by the constant false alarm rate (CFAR) detection method, thus effectively deceiving the enemy.

[0145] The theoretical model of this invention is verified and analyzed below based on simulation results. The target SAR system is assumed to operate in strip frontal-side-looking imaging mode, with an operating frequency band of [frequency band information missing]. The SAR platform has an altitude of 6000m, a flight speed of 150m / s, a SAR antenna length of 0.60m, and an adjacent channel spacing of 0.50m. The carrier frequency is 9.5933GHz, the signal bandwidth is 490MHz, and the pulse duration is... The range sampling frequency is 127.8MHz, and the pulse repetition frequency is 900Hz. The synthetic aperture length is 690 meters, with a range resolution of 0.30m and an azimuth resolution of 0.30m.

[0146] False moving point targets are generated using phase-compensated signals. Real moving point targets are generated based on the slant range between the SAR platform and the moving point targets. In this simulation scenario, the coordinates of the scene center are assumed to be... m, the jammer is located in the center of the scene. All simulation experiments were conducted on a computer with the following hardware configuration: CPU: Intel Xeon Gold 5218R 2.1 GHz; GPU: NVIDIA GeForce RTX 4080, 16GB; Memory: 64GB.

[0147] To ensure the accuracy and universality of the simulation, four point targets at different positions and speeds were constructed to evaluate the broadening and positional shift of false and real moving point targets at different speeds, as shown in Table 1. T1-T4 represent real targets, and P1-P4 represent false targets. In the actual process, the echo data from the three channels were first processed for imaging. Subsequently, the presence of moving targets was determined by applying phase center offset antenna technology (DPCA) cancellation and constant false alarm rate detection (CFAR). Finally, a refocusing algorithm was used to refocus the detected defocused moving targets. In this part of the simulation, the back projection (BP) imaging algorithm was used to simulate the imaging process before DPCA cancellation to compare the broadening of real and false targets. Then, a traditional SAR autofocus algorithm was applied to refocus the moving targets, thereby enabling a comparison of the shifts between real and false targets.

[0148] Table 1

[0149]

[0150] Figure 3 The energy distribution of echoes from real and spurious moving targets after range compression is shown. By comparison... Figure 3 and Figure 4 It can be observed that the energy distribution of a real moving target with azimuth angular velocity may be longer or shorter than the synthetic aperture length. However, the azimuth angular energy distribution of a false moving target is confined to the synthetic aperture length centered on the jammer's position, which is within... Figure 4 The image is marked with two dashed lines. This is because the maximum length of the interference signal that a SAR can receive is equal to the length of a synthetic aperture.

[0151] Figure 5 and Figure 6 The BP imaging results of the raw echo data for both real and false moving targets are shown separately. The target's velocity causes energy broadening along the azimuth direction and a positional shift of the target in the azimuth direction. By comparison... Figure 5 and Figure 6This allows for a comparison of the energy broadening difference between the false targets and the real targets generated by this method. Using the actual moving target as a reference, the position offset error along the azimuth angle is shown in Table 1. The error is less than 5%, indicating that the energy broadening of the false moving targets generated by this method is approximately equal to that of the real moving targets with the same velocity.

[0152] After DPCA cancellation, the energy of false targets is preserved to some extent, thus allowing false targets to be detected by CFAR. Figure 7 and Figure 8 The refocusing imaging results for real and false targets are shown. By comparison... Figure 7 and Figure 8 The position offset error along the azimuth direction was calculated, as shown in Table 1. The error range is less than 1%, indicating that the position offset of the false moving target is consistent with that of the real moving target in the same motion state within the error range.

[0153] Therefore, this invention can rapidly generate multiple false moving targets with different motion states simultaneously in a jamming scenario using a single jammer, while precisely adjusting the speed, number, and position of the false moving targets. After three-channel SAR-GMTI cancellation, the energy of the deception jamming can be effectively preserved; and the generated false moving targets have high fidelity in the two-dimensional time domain, which can mask real moving targets in the scene.

[0154] like Figure 9 As shown, an embodiment of the present invention provides a SAR time-domain high-fidelity moving target single-base deception jamming device, comprising:

[0155] The signal reception module is used to detect and receive signals transmitted by the target SAR system.

[0156] The downconversion module is used to perform downconversion processing on the received SAR signal;

[0157] The analog-to-digital converter module is used to convert the intercepted target SAR transmitted signals into digital signals.

[0158] The signal parameter measurement module is used to measure signal parameters such as pulse width, bandwidth, and pulse repetition frequency of the received signal.

[0159] A two-dimensional time-domain coupled phase modulation module is used to add the phase characteristics of a real moving target to the intercepted signal in order to simulate the same position offset effect and similar energy broadening effect as a real moving target;

[0160] The jamming area position control module is used to control the position of the entire area covered by the jammer;

[0161] The multi-target rapid generation module is used to control the different positions of the same type of moving targets in the scene;

[0162] The parallel processing and superposition module for interference signals is used to generate false moving target groups with different motion states and reduce the time for generating interference signals.

[0163] The digital-to-analog converter module converts the acquired digital interference signal into an analog signal;

[0164] The upconversion module is used for upconversion processing of analog interference signals;

[0165] The transmitting module is used to transmit interference signals pulse by pulse.

[0166] The present invention also provides a storage medium, which is a computer-readable storage medium capable of storing a computer program. When the program is executed by a processor, the device where the storage medium is located executes a SAR time-domain high-fidelity moving target single-base deception jamming method disclosed in the present invention.

[0167] This invention also provides an electronic device, including an antenna unit, a processor unit, and a storage unit. The antenna unit includes pulse antennas and array antennas, primarily used for receiving signals transmitted by a target SAR system and transmitting jamming signals. The processor unit includes a central processing unit, a digital signal processor, and a field-programmable gate array, primarily used for calling and executing various programs to achieve functions such as down-conversion, analog-to-digital conversion, signal parameter measurement, phase modulation with two-dimensional time-domain coupling, jamming area location control, rapid multi-target generation, parallel computation and superposition of jamming signals, digital-to-analog conversion, and up-conversion. The storage unit includes a digital radio frequency memory, a portable hard disk, and a read-only memory, primarily used for storing signal data and programs. When the program in the memory is executed by the processor, the electronic device executes the method of this invention.

[0168] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, 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 embodiments of the present invention can be implemented using various computer languages.

[0169] This 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 will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can 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, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0170] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0171] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0172] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0173] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A SAR time domain high-fidelity moving target deception jamming method, characterized in that, The method comprises the following steps: Step one, obtaining the signal parameters of the signal transmitted by the SAR platform, and generating an initial signal of additional two-dimensional time domain coupled modulation phase; Step two, determining the center position of the false target group, designing the interference region position control template, multiplying the initial signal to obtain the multiplied signal, and controlling the interference region position; Step three, designing a multi-target fast generation template according to the initial position coordinates of the false moving target, multiplying the multiplied signal in step two to generate multiple false moving target signals with consistent speed; Step four, for different speed false moving targets, the two-dimensional time domain coupled modulation phase and the multi-target fast generation template are designed and operated in parallel, and multiple groups of interference signals are superimposed to obtain the final interference signal; Step five, the final interference signal is subjected to digital-to-analog conversion and up-conversion processing, and is forwarded to the target SAR system pulse by pulse to realize the generation of multiple high-fidelity false moving targets with different motion states by a single jammer.

2. The SAR time-domain high-fidelity moving target indication single-station deception jamming method according to claim 1, characterized in that, In step one, the jammer stores the signal into a digital radio frequency memory through down-conversion processing and digital-to-analog conversion, measures the carrier frequency, frequency modulation, and azimuth sampling rate of the signal, and preliminarily detects the distance and height from the SAR platform to the jammer, and then generates an initial signal of additional two-dimensional time domain modulation phase of the simulated real moving target.

3. The method of claim 1, wherein the SAR time domain high-fidelity moving target deception jamming is characterized by, In step two, the design of the interference region position control template is based on the center position of the false target group, and the initial signal after distance direction fast Fourier transform is multiplied to realize accurate control of the interference region position, so that the false moving targets are distributed near the specified center region.

4. The method of claim 1, wherein the SAR time domain high-fidelity moving target deception jamming is characterized by, In step three, the multi-target fast generation template is used to generate multiple false moving targets with consistent speed, and is multiplied with the multiplied signal in step two, and is subjected to distance direction Fourier transform to distance frequency and azimuth time domain signal, so that multiple false moving target points with the same motion state are quickly generated in the scene.

5. The method of claim 1, wherein the SAR time domain high-fidelity moving target deception jamming is characterized by, In step four, for different speed false moving targets, the two-dimensional time domain coupled modulation phase and the multi-target fast generation template are designed and operated in parallel, and then multiple groups of interference signals are superimposed to obtain the final interference signal for confusing the SAR system moving target detection.

6. The method of claim 1, wherein the SAR time domain high-fidelity moving target deception jamming is characterized by, In step five, the digital interference signal after modulation is converted into an analog interference signal by using a digital-to-analog converter, and the jammer forwards the signal to the target SAR system pulse by pulse after up-conversion processing, so that the false moving target can be generated on the SAR image, and can be detected by the constant false alarm detection method after being cancelled by the phase center offset antenna technology.

7. The method of claim 1, wherein the SAR time domain high-fidelity moving target deception jamming is characterized by, A single jammer is used to generate multiple high-fidelity false moving targets with different motion states, and the energy spread and position offset in the azimuth direction are consistent with those of the real moving targets with the same motion state.

8. A SAR time domain high-fidelity moving target deception jamming device, characterized in that, A SAR time domain high-fidelity moving target single-base deception jamming method for realizing any one of claims 1-7 comprises the following modules: A signal interception module for intercepting and receiving the signal transmitted by the target SAR system; A down-conversion module for down-converting the received SAR signal; An analog-to-digital conversion module for converting the intercepted target SAR transmission signal sample into a digital signal; A signal parameter measurement module is configured to measure the pulse width, bandwidth and pulse repetition frequency of the received signal. A two-dimensional time-domain coupled phase modulation module is configured to add the phase characteristics of the real moving target to the intercepted signal to simulate the same position offset effect and similar energy spread effect as the real moving target. An interference region position control module is configured to control the position of the whole region covered by the jammer. A multi-target rapid generation module is configured to control different positions of the same type of moving target in the scene. An interference signal parallel operation and superposition module is configured to generate groups of false moving targets in different motion states and reduce the time for generating the interference signal. A digital-to-analog conversion module is configured to convert the obtained digital interference signal into an analog signal. An up-conversion module is configured to perform up-conversion processing on the analog interference signal. A transmitting module is configured to transmit the interference signal pulse by pulse.

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, The processor executes the program to implement the steps of the SAR time-domain high-fidelity moving target single-base deception jamming method according to any one of claims 1 to 7. 10.A non-transitory computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the steps of the SAR time-domain high-fidelity moving target single-base deception jamming method according to any one of claims 1 to 7.

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