A method and device for locating a jammer against two-dimensional deception jamming of a SAR

Abstract

The application provides a method and device for positioning an interferometer against two-dimensional deception jamming, and belongs to the field of electronic support system synthetic aperture radar countermeasure, comprising: establishing a geometric model of single baseline interferometric SAR against deception jamming; using single baseline interferometric SAR for one-time observation imaging; positioning a false target by using the particularity of the interference phase of a jamming signal, and inversely calculating the range position of the interferometer; establishing a mathematical relationship between the position deviation of the false target and the azimuth position of the interferometer; obtaining the position deviation of the false target in two SAR images by using image domain measurement, combining the obtained range position of the interferometer and other information, inversely calculating the azimuth position of the interferometer, and thus determining the two-dimensional position of the interferometer. The application can position all types of deception jamming including range deception jamming, azimuth deception jamming and two-dimensional deception jamming by using only two signal channels and one-time observation imaging.

Description

Technical Field

[0001] The present invention belongs to the field of Electronic Support Measures (ESM) synthetic aperture radar (SAR) countermeasures, and in particular relates to a jammer positioning method and device for SAR anti-two-dimensional deception jamming. Background Art

[0002] Synthetic aperture radar (SAR), with its all-day, all-weather, high-resolution imaging capabilities, holds significant application value in environmental monitoring, terrain mapping, and intelligence gathering. However, with the advancement of SAR imaging technology, jamming techniques targeting SAR have become increasingly sophisticated, particularly deceptive jamming, which creates false images that are highly fused with the real target, resulting in high concealment and difficulty in suppression, posing a serious threat to SAR imaging reconnaissance.

[0003] Existing anti-spoofing jamming methods are mainly divided into two categories: single-channel and multi-channel. Single-channel anti-interference methods rely on the defects of the deceptive jamming modulation algorithm and suppress interference through parameter agility or time-frequency analysis. However, as the deceptive jamming algorithm is optimized, the anti-interference effectiveness of these methods gradually weakens. Multi-channel anti-interference methods provide additional spatial degrees of freedom, detect the deviation of the interference signal and locate it, and then use filtering to suppress the interference, which has better anti-interference effect. However, existing multi-channel anti-interference methods have the following problems:

[0004] 1. Limited anti-interference types: Some methods can only handle deceptive interference in specific directions (such as range or azimuth) and cannot effectively deal with multi-dimensional interference.

[0005] 2. Large number of signal channels: Multiple signal channels (such as three or four) are required to achieve jammer positioning and interference suppression, which increases system complexity and cost.

[0006] 3. Many observation times: Some methods require multiple observations and imaging from different perspectives. In practical applications, it is difficult to ensure that the same interference signal is received in each observation, resulting in limited anti-interference capabilities. Summary of the Invention

[0007] To address the problems of existing multi-channel SAR anti-deception jamming methods, the present invention proposes a SAR anti-two-dimensional deception jammer positioning method and device. First, a framework for extracting the deviation of deception jammers in the two signal channels of a single-baseline interferometric SAR is proposed. Then, a unified mathematical relationship between the interference deviation and the jammer position is established, thereby using the extracted interference deviation to locate the jammer. After locating the jammer, interference suppression can be achieved by combining it with spatial filtering technology. This method only requires two signal channels and one observation imaging to locate jammers of all types of deception jammers, including range deception jammers, azimuth deception jammers, and two-dimensional deception jammers, which has obvious advantages over existing methods.

[0008] In order to achieve the above object, the present invention adopts the following technical solutions:

[0009] A SAR jammer positioning method for resisting two-dimensional deception jamming comprises the following steps:

[0010] Step 1: Establish a geometric model for single-baseline interferometric SAR anti-spoofing jamming and determine the range deviation of the deceptive jamming signal in the two signal channels;

[0011] Step 2: Use single-baseline interferometric SAR to perform an observation imaging, perform interferometric processing on the two acquired SAR images, and obtain the interferometric phase of the real signal and the interference signal;

[0012] Step 3: Use the particularity of the interference phase of the jamming signal to locate the false target and invert the range position of the jammer;

[0013] Step 4: Based on the range deviation of the jamming signal, a mathematical relationship between the false target position deviation and the jammer azimuth position is established;

[0014] Step 5: Use image domain comparison to obtain the position deviation of the false target in the two SAR images. Combined with the obtained jammer range position and other information, the azimuth position of the jammer is inverted to determine the two-dimensional position of the jammer.

[0015] The present invention also provides a SAR jammer positioning device that resists two-dimensional deception interference, comprising the following modules:

[0016] Model building module, which builds the geometric model of single baseline interferometric SAR anti-spoofing jamming and determines the distance history deviation of the deception jamming signal in the two signal channels;

[0017] The interference processing module uses a single-baseline interferometric SAR to perform an observation imaging, performs interference processing on the two acquired SAR images, and obtains the interference phase of the real signal and the interference signal;

[0018] The inversion module uses the particularity of the interference phase of the jamming signal to locate the false target and invert the range position of the jammer;

[0019] The position establishment module establishes a mathematical relationship between the false target position deviation and the jammer's azimuth position based on the range deviation of the jamming signal;

[0020] The position determination module uses image domain comparison to obtain the position deviation of the false target in the two SAR images. Combined with the obtained jammer range position and other information, it inverts the azimuth position of the jammer, thereby determining the two-dimensional position of the jammer.

[0021] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, the steps of the above-mentioned jammer positioning method based on single-baseline interferometric SAR and resistant to two-dimensional deception interference are implemented.

[0022] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the steps of the above-mentioned jammer positioning method based on single-baseline interferometric SAR and resistant to two-dimensional deception interference are implemented.

[0023] Beneficial effects:

[0024] 1. This method requires only two signal channels for a single observation and imaging, and can extract deceptive interference deviations through interferometric processing and image domain comparison. Compared to existing methods, this method requires fewer system channels and fewer observations.

[0025] 2. This invention can locate all types of deceptive jammers, including range deceptive jammers, azimuth deceptive jammers, and two-dimensional deceptive jammers. Compared to existing methods, this method is more comprehensive in its anti-deceptive jamming capabilities. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Schematic diagram of the geometric model of the airborne single-baseline interferometric SAR anti-spoofing jamming provided by the present invention;

[0027] Figure 2 A flowchart of a SAR jammer positioning method for resisting two-dimensional deception jamming provided by the present invention;

[0028] Figure 3 for" Schematic diagram of the distance history of the real signal and the interference signal in the ideal case of a "spontaneous transmission and self-reception" channel;

[0029] Figure 4 for" hair Schematic diagram of the distance history of the real signal and the interference signal under ideal conditions in the receiving channel;

[0030] Figure 5 for" hair Schematic diagram of the distance history of the real signal and the interference signal in the actual situation in the "receive" channel;

[0031] Figure 6 for" Schematic diagram of the simulation imaging results of the "spontaneous emission and self-reception" channel point target;

[0032] Figure 7 for" hair Schematic diagram of the simulation imaging results of the “receive” channel point target;

[0033] Figure 8 for" Schematic diagram of the simulation imaging results of the "spontaneous transmission and self-reception" channel scenario;

[0034] Figure 9 for" hair Schematic diagram of the simulation imaging results of the "receive" channel scene;

[0035] Figure 10 This is a schematic diagram of the single baseline interferometry processing results for the scene simulation;

[0036] Figure 11 for" Schematic diagram of imaging details of false target A in the "spontaneous transmission and self-reception" channel scenario simulation;

[0037] Figure 12 for" hair Schematic diagram of imaging details of the simulated false target A in the "receive" channel scenario;

[0038] Figure 13 This is a schematic diagram of the SAR jammer positioning device for resisting two-dimensional deception jamming of the present invention. DETAILED DESCRIPTION

[0039] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is 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 intended to illustrate the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0040] like Figure 2 As shown, a SAR jammer positioning method for resisting two-dimensional deception jamming of the present invention comprises the following steps:

[0041] Step 1: Establish a geometric model for single-baseline interferometric SAR anti-spoofing jamming and determine the range deviation of the deceptive jamming signal in the two signal channels;

[0042] Step 2: Use single-baseline interferometric SAR for observation imaging, perform interferometric processing on the two acquired SAR images, and obtain the interferometric phase of the true signal and the interference signal;

[0043] Step 3: Use the particularity of the interference phase of the jamming signal to locate the false target and invert the range position of the jammer;

[0044] Step 4: Using the range deviation of the jamming signal, establish a mathematical relationship between the false target position deviation and the jammer's azimuth position;

[0045] Step 5: Use image domain comparison to obtain the position deviation of the false target in the two SAR images, and use the position deviation and other information obtained to invert the azimuth range of the jammer.

[0046] Specifically, the step 1 includes:

[0047] Step 1.1, create Figure 1 The geometric model of single-baseline interferometric SAR anti-spoofing jamming is shown.

[0048] Two aircraft equipped with SAR systems are flying along the same route. Axis direction with speed At a height of Main antenna Deployed on the aircraft at the front of the formation, it transmits and receives signals to build a " "Self-transmitting and self-receiving" signal channel. From the antenna Deployed on the aircraft at the rear of the formation, it only receives signals and builds a " hair The imaging results of the two signal channels can be processed by interference, and the baseline length is With the main antenna The projection on the ground is the coordinate origin The jammer is located at point The false target generated by the jammer modulation is located at point . and Represents any target to antenna in the imaging scene and distance. and They respectively represent the distance that the false target deviates from the jammer in azimuth and ground range.

[0049] In this scenario, the SAR transmits a linear frequency modulation signal, and the antenna The received echo of the real signal is expressed as:

[0050] (1)

[0051] in, and They represent distance time and azimuth time respectively. represents the distance envelope function, represents the azimuth envelope function, represents the zero Doppler time, represents the frequency modulation slope, represents the backscatter coefficient of the real target, Indicates target to antenna The instantaneous slope distance , j is the imaginary unit, represents the exponential function, represents the speed of light, Indicates the carrier frequency of the linear frequency modulation signal.

[0052] Step 1.2: Establish a mathematical model of the deceptive jamming signal received by the interferometric SAR.

[0053] The signal intercepted by the jammer is expressed as:

[0054] (2)

[0055] in, Indicates the jammer to antenna The jammer can know the main antenna distance in advance through side lobe reconnaissance. The position and SAR signal parameters are then used to modulate the intercepted signal using the reconnaissance information to generate a two-dimensional deception jamming signal. Deception jamming signal The modulation process is as follows:

[0056] (3)

[0057] in, is the unit impulse function, The position of the false target and the jammer relative to the antenna The distance course difference, that is, the distance course that the jammer needs to modulate, is the backscatter coefficient of the false target.

[0058] The jammer modulates the signal and transmits it to the SAR receiver. Received deceptive jamming signal The expression is as follows:

[0059] (4)

[0060] where, represents the instantaneous slant range from the jammer to the antenna . The information of the main antenna is obtained by the jammer through the sidelobe reconnaissance, so the jamming signal received by the jammer is accurately modulated, and a perfect false target can be formed.

[0061] Step 1.3, obtain the slant range modulation deviation of the deceptive jamming signal appearing in the two signal channels.

[0062] The information of the antenna is unknown to the jammer, so the jamming signal received by the jammer is not perfect, and the perfect jamming signal received by the jammer should be:

[0063] (5)

[0064] where, is the difference between the distance history of the false target and the jammer relative to the antenna . The difference between formula (5) leads to the deviation of the phase and compression position of the false target formed by the "transmit-receive" signal channel. This deviation is closely related to the position of the jammer, and the position information of the jammer can be obtained by extracting the deviation. Specifically, the step 2 comprises:

[0065] Step 2.1, image registration is performed on the two SAR images.

[0066] Firstly, simple translation based on known homonym points is performed to realize coarse registration. The homonym points are selected by manual selection method.

[0067] Then, coherent coefficient method is used for image fine registration: the coherent coefficient of each pixel in its matching window is calculated, and the homonym point is selected as the one with the maximum coherent coefficient, and fine registration is completed.

[0068] Step 2.2, the two SAR images and

[0069] after registration are conjugate multiplied and the principal value of the argument is taken, so as to obtain the interference phase image .

[0070] (6) ​​​​

[0071] in, Indicates the principal value of the complex number, the superscript represents the conjugation operation.

[0072] Step 2.3, use the Goldstein filtering method to filter the interference phase image Perform phase filtering to remove phase noise.

[0073] The process of this filtering method can be briefly described as follows: the interference phase map Convert to vector space and is divided into multiple overlapping small blocks , perform a two-dimensional Fourier transform on each small block to obtain its spectrum information , select the kernel function Normalize the spectrum and construct weighting coefficients Process the spectrum to get the result of each small block, merge the blocks and get the main phase value to get the filtering result. .

[0074] Step 2.4, calculate the flat-earth phase of the single baseline interferometer, and subtract the flat-earth phase from the filtered phase to obtain .

[0075] Flat Earth Phase The calculation formula is:

[0076] (7)

[0077] In step 2.5, the least squares phase unwrapping method is used to perform interferometric phase unwrapping. The basic idea is to minimize the sum of the squares of the differences between the discrete partial derivatives of the wrapped phase and the discrete partial derivatives of the true phase.

[0078] Step 2.6, true phase recovery, adds the unwrapped phase to the ground phase, and after correcting the system deviation based on a known phase point, obtains the true phase map of the imaging scene. .

[0079] Specifically, step 3 includes:

[0080] Step 3.1: Analyze the interference phase difference between the false target and the real target.

[0081] Observing the difference between formula (1) and formula (4) in the first exponential term, we can find that although the main antenna The phase characteristics of the interference signal received are ideal, but the The phase characteristics of the received jamming signal are deviated. Therefore, the interference phase of the jamming signal deviates from the real signal. By quantitatively analyzing this difference, the distance and position information of the jammer can be obtained.

[0082] The interferometric phase modeling process is as follows:

[0083] Use slope distance Replace ground distance and height , any real point target position Relative to the main antenna Location and from the antenna Location The slope distance is expressed as:

[0084] (8)

[0085] (9)

[0086] The expression for the interference phase of the real point target is:

[0087] (10)

[0088] The interference phase of the real target is determined by the interference baseline length and its distance position. When the baseline changes slightly, it can be considered that the interference phase and the target distance position correspond one to one. Similarly, if the deceptive interference signal is interfered with, the false target The interference phase Expressed as:

[0089] (11)

[0090] in, is the interference phase of the real target at the jammer position.

[0091] Step 3.2: Utilize the interference phase characteristics of the false target to locate the false target.

[0092] It can be found that the interference phase of the false target is not determined by its location, but by the location of the jammer, and is related to the interference phase of the real target at the jammer location. Because the interference phase of the real target changes with the distance, and the interference phase of each point in the false target is the same, the difference between the two is obvious, so the false target can be located. Location Already got it.

[0093] Step 3.3, use the interference phase inversion of the false target obtained by interference processing to obtain the jammer's range position.

[0094] Using formula (11) to invert the interference phase of the false target, the distance position of the jammer is obtained :

[0095] (12)

[0096] Further, the difference between the range position of the false target and the range position of the jammer is calculated to obtain the distance of the false target deviating from the jammer in the range direction . This value will be used for the jammer azimuth direction positioning in step 5.

[0097] Specifically, the step 4 includes:

[0098] Step 4.1, analyzing the compressed position difference between the false target and the real target.

[0099] Observing the difference in the first exponential term and the difference in the second exponential term of the formula (4) and the formula (5), it can be found that the interference signal received by the main antenna can be correctly compressed to its ideal position , but the compressed position of the interference signal received by the antenna has a deviation. By modeling the range history of the real signal and the interference signal in the two signal channels, the influence of the range history deviation of the false target on its compressed position deviation can be quantitatively analyzed.

[0100] Step 4.2, establishing the range model of the real target and the false target modulated by the jammer in the "self-transmitting and self-receiving" channel, as shown in the formula (6), wherein, is the synthetic aperture length of the SAR. Figure 3 In order to simplify the expression of the slant range, it is considered that the range history from the main antenna to the ground is the same for the two signal channels, so the following analysis only considers the range history from the ground to the antenna. In addition, in order to highlight the difference in the range history of different channels, the bending degree of the slant range curve in the figure is increased.

[0101] The accurate expression of the range history is:

[0102] (13)

[0103] (14)

[0104] (14)

[0105] wherein, is the range history of the real signal at the jammer position, is the range history of the interference signal emitted by the jammer and imaged at the point , and is the distance of the false target deviating from the jammer in the range direction.

[0106] ​​The difference between the two is the jammer's The distance history of the "spontaneous transmission and self-reception" signal channel modulation , expressed as:

[0107] (15)

[0108] Step 4.3, create hair In the receiving channel, the distance model between the real target at the jammer and the false target formed by modulation is as follows: Figure 4 shown.

[0109] is the distance history of the real signal at the jammer location, The ideal signal emitted by the jammer should be as follows: The distance history of the interference signal at point . The exact expression of the distance history is:

[0110] (16)

[0111] (17)

[0112] The difference between the two is that the jammer targets " hair The distance course that the receiving channel should modulate , expressed as:

[0113] (18)

[0114] Step 4.4: Based on the distance course difference between the two signal channels, establish a mathematical relationship between the false target position deviation and the jammer azimuth position.

[0115] Because the spatial freedom of a single-station jammer is smaller than that of a single-baseline interferometric SAR, its When the "self-transmitting and self-receiving" channel is ideally interfered, it is impossible to hair Therefore, the antenna The distance history of the actual interference signal received is not and of and, but and The sum of ,like Figure 5 shown.

[0116] Ideal distance course The false target will be compressed in the correct position. The actual distance course This will cause a deviation in the compression position of the false target. The expression is:

[0117] (19)

[0118] The time-invariant term in the above formula will cause the range deviation of the compressed position of the false target, and the time-varying term will cause a slight defocus of the target and an azimuth deviation of the compressed position. Using this formula, the mathematical relationship between the range deviation of the compressed position of the false target and the jammer position can be established:

[0119] (20)

[0120] Specifically, step 5 includes:

[0121] In step 5.1, the position deviation of the false target is measured in the two SAR images.

[0122] Based on the false target position obtained in step 3, the compressed position range deviation is obtained by comparing and measuring the two SAR images using an image analysis method. .

[0123] For a false target containing a large number of scattering points, several scattering points with the strongest scattering characteristics are extracted, the range position deviations of these scattering points are calculated, and the average is taken as the position deviation of the false target.

[0124] When measuring the distance deviation between scattering points, fragment upsampling is required to further improve the measurement accuracy.

[0125] Step 5.2: Based on the measured position deviation results and other information obtained previously, the azimuth distance of the jammer is inverted.

[0126] and Already calculated in step 3, combined with the known baseline length , the distance of the false target from the jammer in azimuth can be inverted :

[0127] (twenty one)

[0128] Step 5.3, obtain the jammer's azimuth position based on the azimuth spacing, and combine it with the previously obtained information to finally determine the jammer's two-dimensional position.

[0129] The azimuth position of the false target obtained when the jammer is positioned in the range direction , subtract the spacing from this value The jammer's azimuth position can be obtained At this point, the two-dimensional position of the jammer Already got it.

[0130] Example:

[0131] The operating parameters of a typical high-altitude, long-endurance, unmanned aerial vehicle-mounted high-resolution SAR in strip mode are shown in Table 1. To meet the requirements of phase unwrapping in interferometric processing, the baseline length is set to 400m.

[0132] Table 1 Working parameters

[0133]

[0134] The first set of simulations is a point target simulation, the purpose of which is to prove the effectiveness of the method. In this scenario, the jammer is placed in the center of the imaging scene. The jammer modulates the intercepted SAR signal to generate The deception point target. False point target formed by antenna receiving signal like Figure 6 As shown in the figure, the false target in this image is located at the ideal position expected by the jammer. False point target formed by antenna receiving signal like Figure 7 As shown in the figure, the position of the false target in the image deviates from the ideal position expected by the jammer.

[0135] The proposed method is used to locate the jammer. First, the imaging result of the pseudo point target is interfered and inverted to obtain . Then use the fake point target Coordinates ,get . Further measurement of pseudo point targets and Distance deviation of compression position , inversion yields Finally, combined with the known Determine the jammer's position The calculation results, shown in Table 2, are generally consistent with the real data. This positioning accuracy meets the requirements of subsequent applications such as spatial filtering. Therefore, the effectiveness of this positioning method is demonstrated.

[0136] Table 2 Calculation results

[0137]

[0138] The second set of simulations is a multi-target deception simulation based on a real scene, the purpose of which is to verify the effectiveness of the method in a real SAR confrontation environment. The multi-target simulation experiment is carried out based on the real SAR images obtained by the Taijing 4 satellite. In this scenario, the jammer is placed at By modulating the intercepted SAR signal, three false ship targets A, B, and C are generated and distributed at different locations on the sea surface. The SAR image after interference is as follows: Figure 8 and Figure 9 As shown in , the positions of the three false targets are different between the two images, that is, there is a position deviation. Taking false target A as an example, its position deviation is as follows Figure 11 and Figure 12 shown.

[0139] The present invention is used to locate the jammer. First, two SAR images are interferometrically processed. The processing results are shown in the figure below. Figure 10 As shown in the figure, three false ship targets can be clearly identified from the interference pattern. After that, the distance position information of the jammer is inverted using the real interference phase after the false target is unwound. Furthermore, by measuring the distance deviation of the three ship targets in the two images, the azimuth position information of the jammer can be inverted. Considering that the scattering characteristics of the actual target are more complex, the inversion method adopts the method of calculating and averaging multiple strong scattering points in the target separately, for example Figure 11 and Figure 12 The offset of the characteristic scattering point P1 to P2 and the offset of Q1 to Q2 in the image are shown in Table 3. The inversion results of the jammer position information using three ship targets are shown in Table 3.

[0140] Table 3 Inversion results

[0141]

[0142] The inversion results of the three false ship targets, compared with the jammer's true position, all showed errors within the acceptable range for spatial filtering techniques. Comparing the three positioning results also reveals that the closer the false target is to the jammer in range or azimuth, the smaller the positioning error in the corresponding direction. Averaging the three positioning results further improves positioning accuracy, fully meeting the requirements of spatial filtering for jamming suppression. This demonstrates the effectiveness of this positioning method in a real-world SAR adversarial environment.

[0143] In summary, the present invention is based on a single baseline interferometric SAR system and only requires two signal channels for one imaging observation. One of them is “ The other is the "self-transmitting and self-receiving" signal channel. hair Secondly, the present invention proposes a framework for extracting the deviation of the deceptive jamming signal in the two signal channels of the single-baseline interferometric SAR. On the one hand, this framework extracts the phase characteristic deviation of the deceptive jamming signal through interferometric processing, and on the other hand, it extracts the compressed position deviation of the deceptive jamming signal through image domain comparison. Thirdly, the present invention establishes a mathematical relationship between the interference phase of the deceptive jamming target and the jammer position. After obtaining the true interference phase of the deceptive jamming through interferometric processing, the jammer distance position information can be inverted. Finally, the present invention establishes a mathematical relationship between the compressed position deviation of the deceptive jamming signal and the jammer position. After obtaining the compressed position deviation through image domain comparison, the jammer azimuth position information can be inverted in combination with the interferometric processing results.

[0144] like Figure 13 As shown, the present invention also provides a SAR jammer positioning device that is resistant to two-dimensional deception jamming, which is used to implement the above method and includes the following modules:

[0145] Model building module, which builds the geometric model of single baseline interferometric SAR anti-spoofing jamming and determines the distance history deviation of the deception jamming signal in the two signal channels;

[0146] The interference processing module uses a single-baseline interferometric SAR to perform an observation imaging, performs interference processing on the two acquired SAR images, and obtains the interference phase of the real signal and the interference signal;

[0147] The inversion module uses the particularity of the interference phase of the jamming signal to locate the false target and invert the range position of the jammer;

[0148] The position establishment module establishes a mathematical relationship between the false target position deviation and the jammer's azimuth position based on the range deviation of the jamming signal;

[0149] The position determination module uses image domain comparison to obtain the position deviation of the false target in the two SAR images. Combined with the obtained jammer range position and other information, it inverts the azimuth position of the jammer, thereby determining the two-dimensional position of the jammer.

[0150] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, the steps of the above-mentioned jammer positioning method based on single-baseline interferometric SAR and resistant to two-dimensional deception interference are implemented.

[0151] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the steps of the above-mentioned jammer positioning method based on single-baseline interferometric SAR and resistant to two-dimensional deception interference are implemented.

[0152] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk drives, CD-ROMs, optical storage devices, etc.) containing computer-usable program code. The solutions in the embodiments of the present invention may be implemented using various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0153] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts 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, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0154] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0155] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0156] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0157] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A SAR jammer positioning method for resisting two-dimensional deception jamming, characterized in that: The following steps are involved: Step 1: Establish a geometric model for single-baseline interferometric SAR anti-spoofing jamming and determine the range deviation of the deceptive jamming signal in the two signal channels; Step 2: Use single-baseline interferometric SAR to perform an observation imaging, perform interferometric processing on the two acquired SAR images, and obtain the interferometric phase of the real signal and the interference signal; Perform interferometric processing on the two acquired SAR images, including: Image registration is performed on two SAR images. First, a simple translation based on known points of the same name is performed to achieve coarse registration, and then the coherence coefficient method is used to perform fine image registration. The two registered SAR images are conjugate multiplied and the principal value of the argument is taken to obtain the interferometric phase map; The Goldstein filtering method is used to perform phase filtering on the interference phase image to remove phase noise; Calculate the flat-earth phase of the single-baseline interferometer and subtract the flat-earth phase from the filtered phase; Interferometric phase unwrapping is performed using the least squares phase unwrapping method; Perform true phase recovery to obtain the true phase map of the imaging scene; Step 3: Use the particularity of the interference phase of the jamming signal to locate the false target and invert the range position of the jammer; Step 4: Based on the range deviation of the jamming signal, a mathematical relationship between the false target position deviation and the jammer azimuth position is established; Step 5: Use image domain comparison to obtain the position deviation of the false target in the two SAR images. Combined with the obtained jammer range position and other information, the azimuth position of the jammer is inverted to determine the two-dimensional position of the jammer.

2. The SAR jammer positioning method for resisting two-dimensional deception jamming according to claim 1, characterized in that: In step 1, establishing a geometric model for single-baseline interferometric SAR anti-spoofing jamming includes: Determine the formation pattern for two SAR-equipped aircraft flying along the same route, as well as the locations for deploying the primary and secondary antennas, and establish the "primary transmitter, primary receiver" and "primary transmitter, secondary receiver" signal channels. Determine the positional relationship between the jammer and the false target, as well as the distance from the target to the antenna in the imaging scene; Establish the echo expression of SAR transmitted signal and received real signal; Establish the expression of the signal intercepted by the jammer, as well as the process of the jammer modulating to generate the deceptive jamming signal and the expression of the received deceptive jamming signal; Obtain the slant range modulation deviation of the deceptive jamming signal in the two signal channels.

3. The SAR jammer positioning method for resisting two-dimensional deception jamming according to claim 1, characterized in that: In step 3, the particularity of the interference phase of the jamming signal is used to locate the false target and inversely calculate the range position of the jammer, including: By analyzing the interference phase difference between the false target and the real target, it is found that the interference phase of the false target is determined by the location of the jammer and is different from the interference phase of the real target, thus achieving false target positioning; The interference phase inversion of the false target is used to obtain the range position of the jammer, and the distance that the false target deviates from the jammer in the range direction is calculated.

4. The SAR jammer positioning method for resisting two-dimensional deception jamming according to claim 1, characterized in that: In step 4, based on the range deviation of the jamming signal, a mathematical relationship between the false target position deviation and the jammer azimuth position is established, including: Analyze the difference in compressed position between the false target and the real target, and establish the distance model between the real target and the false target formed by modulation at the jammer in the two signal channels; According to the distance course difference between the two signal channels, a mathematical relationship between the false target position deviation and the jammer azimuth position is established.

5. The SAR jammer positioning method for resisting two-dimensional deception jamming according to claim 1, characterized in that: In step 5, the position deviation of the false target in the two SAR images is obtained by image domain comparison, and the azimuth position of the jammer is inverted, including: The position deviation of the false target is measured in two SAR images. For a false target containing a large number of scattering points, the scattering points with the strongest scattering characteristics are extracted, and the range position deviation of these scattering points is calculated and averaged. According to the measured position deviation results and the previously obtained jammer range position and other information, the azimuth distance of the jammer is inverted to determine the two-dimensional position of the jammer.

6. The SAR jammer positioning method for resisting two-dimensional deception jamming according to claim 1, characterized in that: It is applicable to various types of deception jamming positioning, including range deception jamming, azimuth deception jamming and two-dimensional deception jamming.

7. The SAR jammer positioning method for resisting two-dimensional deception jamming according to claim 1, characterized in that: Only two signal channels are required, and only one observation imaging is required.

8. A SAR jammer positioning device that resists two-dimensional deception jamming, characterized in that: Includes the following modules: Model building module, which builds the geometric model of single baseline interferometric SAR anti-spoofing jamming and determines the distance history deviation of the deception jamming signal in the two signal channels; The interference processing module uses a single-baseline interferometric SAR to perform an observation imaging, performs interference processing on the two acquired SAR images, and obtains the interference phase of the real signal and the interference signal; Perform interferometric processing on the two acquired SAR images, including: Image registration is performed on two SAR images. First, a simple translation based on known points of the same name is performed to achieve coarse registration, and then the coherence coefficient method is used to perform fine image registration. The two registered SAR images are conjugate multiplied and the principal value of the argument is taken to obtain the interferometric phase map; The Goldstein filtering method is used to perform phase filtering on the interference phase image to remove phase noise; Calculate the flat-earth phase of the single-baseline interferometer and subtract the flat-earth phase from the filtered phase; Interferometric phase unwrapping is performed using the least squares phase unwrapping method; Perform true phase recovery to obtain the true phase map of the imaging scene; The inversion module uses the particularity of the interference phase of the jamming signal to locate the false target and invert the range position of the jammer; The position establishment module establishes a mathematical relationship between the false target position deviation and the jammer's azimuth position based on the range deviation of the jamming signal; The position determination module uses image domain comparison to obtain the position deviation of the false target in the two SAR images. Combined with the obtained jammer range position and other information, it inverts the azimuth position of the jammer, thereby determining the two-dimensional position of the jammer.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the steps of the SAR jammer positioning method for resisting two-dimensional deception jamming are implemented as described in any one of claims 1 to 7.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of a SAR jammer positioning method for resisting two-dimensional deception jamming are implemented as claimed in any one of claims 1 to 7.

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