Radio frequency characteristic simulation decoy method based on one-dimensional range profile

Abstract

The invention relates to a one-dimensional range profile-based radio frequency characteristic simulation decoy method, which comprises the following steps of: judging whether to start one-dimensional range profile radio frequency characteristic simulation or not according to a signal sorting and radar working mode identification result; under the starting condition, selecting a scattering point-based simulation mode or a target database-based simulation mode according to judgment, if the scattering point-based simulation mode is selected, setting the number of simulated scattering points and the time delay between the scattering points, calculating the gain of the decoy signal and simulating the fluctuation type of the target; if a target database simulation mode and a real-time attitude angle of a load receiving platform are selected, a radiation source azimuth angle and a pitch angle are converted into a load system angle, a database is retrieved according to the load system angle and a sorted radar signal carrier frequency, and a distance image is obtained; in conclusion, the method has the advantages that the decoy load echo precision is high, and the simulated target object is vivid.

Description

Technical Field

[0001] The invention belongs to the technical field of electronic countermeasures, and in particular relates to a radio frequency feature simulation deception method based on one-dimensional range image. Background Art

[0002] Since the 1980s, foreign countries have begun to develop small platform decoy equipment to simulate real combat equipment. After many years, it has developed into models such as ADM-160C (MALD-J) and MALD-X. At present, my country's decoy load has also begun corresponding technical research and development, but it is still in its infancy. Among them, the decoy load mainly simulates the radio frequency scattering characteristics of its own combat targets and is an important part of simulating real combat equipment. The decoy load mainly includes RCS and one-dimensional range image simulation. At the same time, the one-dimensional range image reflects the structural characteristics of the target along the radar radial direction. When the combat enemy radar is a high-resolution radar, due to its extremely high range resolution, its wavelength is much smaller than the size of the target. At this time, the target can be approximately divided into multiple discrete scattering points. The echo signal of the radar irradiating the target is scattered by multiple points to form scattering point sub-echoes, which can be used. However, different sub-echoes will change in amplitude and phase. At the same time, when the azimuth of the target relative to the radar changes during flight, the relative distance of each scattering center will also cause the target range image to fluctuate. Therefore, there are still some problems in the actual application of the one-dimensional range image reaction.

[0003] An invention patent with application number "CN202111257720.2" titled "A UAV detection, deception system and method" mentions that it includes a multi-band passive radar module, which is communicated with a visual host computer; the position of the illegal UAV is detected in real time by passive radar, and the position of the three-frequency receiver of BUZZ / GPS / GLONAS is combined. After relevant algorithm calculation and coordinate conversion, the final coordinates are used for the coordinates of the decoy signal simulation. This method can greatly improve the accuracy of the simulated coordinates of the decoy signal, making it difficult for illegal UAVs to distinguish the decoy signal, increasing the authenticity of the decoy signal, improving the success rate of decoy, and reducing the time required for decoy, but the decoy simulation technology it uses is still relatively primitive.

[0004] Current decoy simulation technology is divided into passive decoy and active decoy. Passive decoy is mainly implemented using radar reflectors. Due to the limitations of volume and shape, radar reflectors cannot achieve high-precision simulation over a wide band. At the same time, traditional active decoys provide a fixed amplitude for all received signals during use, resulting in the disadvantage of low simulation accuracy. Furthermore, it is impossible to modulate the one-dimensional range profile of the echo signal in the time domain, resulting in low payload echo accuracy and unrealistic simulation of the target object. Summary of the invention

[0005] In view of this, the present invention proposes a radio frequency feature simulation deception method based on one-dimensional range image, which is applied to the field of electronic countermeasure technology and can solve the technical problems of low echo accuracy of existing decoy payloads and unrealistic simulation of target objects.

[0006] In order to achieve the above technical objectives, the specific technical solutions adopted by the present invention are:

[0007] A radio frequency feature simulation deception method based on one-dimensional range profile comprises the following steps:

[0008] S1, collect radiation source signals, complete signal sorting and radar working mode recognition;

[0009] S2. Determine whether to start one-dimensional range profile RF feature simulation based on the signal sorting and radar working mode recognition results;

[0010] S3. If the one-dimensional range profile radio frequency feature simulation is turned on, the following formula is used to determine whether to use the scattering point simulation method or the target database simulation method;

[0011]

[0012] Where N is the maximum number of scattering points that can be independently set on the hardware platform. If the actual length L of the simulated target satisfies the above inequality, the simulation method based on the target database is adopted, otherwise the simulation method based on the scattering points is adopted;

[0013] S4. If the scattering point simulation method is selected, set the number of simulated scattering points and the delay between each scattering point;

[0014] S5, calculating the gain of the decoy signal and simulating the fluctuation type of the target, superimposing the echo signal to obtain a one-dimensional range image echo simulation signal;

[0015] S6. If the simulation method based on the target database is selected, the payload receives the real-time attitude angle of the platform and converts the azimuth and pitch angle of the radiation source into the payload system angle;

[0016] S7. According to the load system angle and the sorted radar signal carrier frequency, the database is retrieved to obtain the real-time one-dimensional range image feature data of the target, and the one-dimensional range image feature information is convolved with the echo signal to obtain a one-dimensional range image echo simulation signal.

[0017] Furthermore, in step S2, when the radiation source is in tracking mode and the radiation source signal bandwidth satisfies B ≥ B th , then a one-dimensional range image radio frequency feature simulation is performed, B th To open the bandwidth threshold of one-dimensional range profile simulation, its calculation formula is:

[0018]

[0019] Where L is the length of the simulated target and C is the speed of light.

[0020] Furthermore, in step S4, the target is divided into K scattering points, and the delay of each scattering point is t i .

[0021] Furthermore, in step S5, the high-resolution radar operates in a linear frequency modulation mode and sets its carrier frequency to f c , the pulse width is T P , the bandwidth is B, then the transmitted signal is expressed as:

[0022]

[0023] The simulated one-dimensional range image fluctuation echo signal emitted by the radio frequency system is:

[0024]

[0025] Among them A i is the gain of each scattering point, where A i satisfy:

[0026] A i =-39+10×log10(σ i )+20×log10(f c )

[0027]

[0028] Among them, σ i The corresponding fluctuation model is selected according to the specific simulated combat objectives. is the average RCS value of the simulated target.

[0029] Furthermore, in step S6, the payload receives the real-time attitude angle of the platform, performs coordinate conversion, converts the azimuth angle and the pitch angle into the payload system angle, and obtains the pitch angle tha and the azimuth angle phi.

[0030] Further, in step S7, according to f c Different target data are selected based on the pitch angle tha and the azimuth angle phi. By selecting the target database data and convolving it with the echo data, a one-dimensional distance simulated based on the target data is obtained.

[0031] By adopting the above technical solution, the present invention can also bring the following beneficial effects:

[0032] 1. The present invention mentions a radio frequency feature simulation deception method based on one-dimensional range profile, which includes two methods: scattering point simulation and target database simulation, both of which can realize amplitude and delay modulation of echo signals. The simulation method based on scattering points has a relatively low degree of fit with the simulated target due to insufficient number of points, but has the characteristics of simple implementation and relatively low precision. The target database method directly uses a one-dimensional database of the simulated target with many sample points, and has the characteristics of relatively complex implementation and high simulation precision. The present invention can select a suitable simulation method according to the real-time battlefield environment and processing resources, and realize whether to turn on the one-dimensional range profile simulation and switch the simulation method by setting judgment conditions, taking into account the advantages of both methods, and realizing high-precision radio frequency feature simulation of the one-dimensional range profile of the simulated target.

[0033] 2. The present invention mentions a radio frequency feature simulation decoy method based on one-dimensional range profile. On the basis of traditional decoy echo simulation, it proposes a method of simulating one-dimensional range profile based on scattering points. It combines the RCS of the combat target, the frequency of the sorting signal and the fluctuation model of the combat target, and dynamically controls the power of the one-dimensional range profile echo to achieve a realistic simulation of the one-dimensional range profile of the combat aircraft. It selects real-time one-dimensional range profile features in the target database according to different attitude angles and different radar signal frequencies, and simulates the one-dimensional range profile features of the combat aircraft with high precision.

[0034] 3. The present invention has a simple structure and is easy to use. It can be used as a decoy equipment and applied to scenes such as tactical cover and consumption of enemy firepower. It is cheap and can reduce the combat cost-effectiveness ratio, improve the development of decoy technology in electronic warfare, and effectively improve the proximity deception effect. It has a very broad market prospect and can significantly improve social benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0036] Figure 1 This is a flow chart of a radio frequency feature simulation deception method based on a one-dimensional range profile in Example 1 of the present invention;

[0037] Figure 2 This is a schematic diagram of a simulation model of a combat target in Example 1 of the present invention;

[0038] Figure 3 Schematic diagram of a one-dimensional range profile signal based on scattering point simulation in Example 1 of the present invention;

[0039] Figure 4It is an echo simulation signal diagram of a one-dimensional range image simulation diagram based on a target database in Example 1 of the present invention;

[0040] Figure 5 This is an echo simulation signal diagram of a one-dimensional range image simulation diagram based on a target database in Example 2 of the present invention. DETAILED DESCRIPTION

[0041] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0042] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention.

[0043] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present invention, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects described herein can be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this device and / or practice this method.

[0044] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention. The drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the shape, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0045] Additionally, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, it will be understood by those skilled in the art that the aspects described may be practiced without these specific details.

[0046] Example 1

[0047] like Figure 1 As shown, the present invention mentions a radio frequency feature simulation deception method based on a one-dimensional range image, comprising the following steps:

[0048] In step S1, the radiation source signal is collected to complete signal sorting and radar working mode recognition;

[0049] In step S2, when the radiation source is in tracking mode and the radiation source signal bandwidth satisfies B ≥ B th , then a one-dimensional range profile radio frequency feature simulation is performed. th To open the bandwidth threshold of one-dimensional range profile simulation, its calculation formula is:

[0050]

[0051] Where L is the length of the simulated target and C is the speed of light;

[0052] In step S3, if the one-dimensional range profile RF feature simulation is turned on, the following formula is used to determine whether to use a scattering point simulation method or a target database simulation method;

[0053]

[0054] Where N is the maximum number of scattering points that can be independently set on the hardware platform; if the actual length L of the simulated target satisfies the above inequality, the simulation method based on the target database is adopted, otherwise the simulation method based on the scattering points is adopted. The simulation model of the combat target is as follows: Figure 2 As shown;

[0055] In step S4, it is assumed that the target can be divided into K scattering points, and the delay of each scattering point is t i ;

[0056] In step S5, it is assumed that the high-resolution radar operates in a linear frequency modulation mode, and its carrier frequency is f c , the pulse width is T P , the bandwidth is B, so the transmitted signal is expressed as:

[0057]

[0058] The simulated one-dimensional range image fluctuation echo signal emitted by the radio frequency system is:

[0059]

[0060] Among them A i is the gain of each scattering point, where A i satisfy:

[0061] A i =-39+10×log10(σ i)+20×log10(f c )

[0062]

[0063] Among them, σ i Because the corresponding fluctuation model is selected according to the specific simulated combat target, σ is the average RCS value of the simulated target;

[0064] The echo simulation signal based on scattering point simulation technology is used. Figure 3 As shown;

[0065] In step S6, the payload receives the real-time attitude angle of the platform, performs coordinate conversion, converts the azimuth angle and pitch angle into the payload system angle, and obtains the pitch angle tha and the azimuth angle phi;

[0066] In step S7, in this embodiment, the carrier frequency is set to 5.5 GHz, the pitch angle tha is 90 degrees, and the azimuth angle phi is 2 degrees to read the target data, wherein a one-dimensional range image based on the target data simulation is obtained by convolving the target data with the echo data, and the echo simulation signal of embodiment 1 is obtained, such as Figure 4 As shown, a realistic simulation of the one-dimensional range image of a combat aircraft is obtained.

[0067] Example 2

[0068] Different from Example 1, in this embodiment, in step S7, the carrier frequency is set to 5.5 GHz, the pitch angle tha is set to 90 degrees, and the azimuth angle phi is set to 10 degrees to read the target data, and the echo simulation signal in Example 2 is obtained, such as Figure 5 As shown, a realistic simulation of the one-dimensional range image of a combat aircraft is obtained.

[0069] In summary, the present invention includes two methods, namely, scattering point simulation and target database simulation, both of which can realize the modulation of the amplitude and delay of the echo signal. By setting the judgment conditions, it is realized whether to turn on the one-dimensional range image simulation and the switching of the simulation mode. It takes into account the advantages of both scattering point simulation and target database simulation, and realizes the high-precision radio frequency feature simulation of the one-dimensional range image of the simulated target. It has the advantages of high precision of the decoy payload echo and realistic simulation of the target object.

[0070] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A radio frequency feature simulation deception method based on one-dimensional range profile, characterized in that: The following steps are involved: S1, collect radiation source signals, complete signal sorting and radar working mode recognition; S2. Determine whether to start one-dimensional range profile RF feature simulation based on the signal sorting and radar working mode recognition results; S3. If the one-dimensional range profile radio frequency feature simulation is turned on, the following formula is used to determine whether to use the scattering point simulation method or the target database simulation method; Where N is the maximum number of scattering points that can be independently set on the hardware platform. If the actual length L of the simulated target satisfies the above inequality, the simulation method based on the target database is adopted, otherwise the simulation method based on the scattering points is adopted; S4. If the scattering point simulation method is selected, set the number of simulated scattering points and the delay between each scattering point; S5, calculating the gain of the decoy signal and simulating the fluctuation type of the target, superimposing the echo signal to obtain a one-dimensional range image echo simulation signal; S6. If the simulation method based on the target database is selected, the payload receives the real-time attitude angle of the platform and converts the azimuth and pitch angle of the radiation source into the payload system angle; S7. According to the load system angle and the sorted radar signal carrier frequency, the database is retrieved to obtain the real-time one-dimensional range image feature data of the target, and the one-dimensional range image feature information is convolved with the echo signal to obtain a one-dimensional range image echo simulation signal.

2. The radio frequency feature simulation deception method based on one-dimensional range profile according to claim 1, characterized in that: In step S2, when the radiation source is in tracking mode and the radiation source signal bandwidth satisfies B≥B th , then a one-dimensional range image radio frequency feature simulation is performed, B th To open the bandwidth threshold of one-dimensional range profile simulation, its calculation formula is: Where L is the length of the simulated target and C is the speed of light.

3. The radio frequency feature simulation deception method based on one-dimensional range profile as claimed in claim 2, characterized in that: In step S4, the target is divided into K scattering points, and the delay of each scattering point is t i .

4. The radio frequency feature simulation deception method based on one-dimensional range profile as claimed in claim 3, characterized in that: In step S5, the high-resolution radar operates in the linear frequency modulation mode, and its carrier frequency is set to f c , pulse width is T P , the bandwidth is B, then the transmitted signal is expressed as: The simulated one-dimensional range image fluctuation echo signal emitted by the radio frequency system is: Among them A i is the gain of each scattering point, where A i satisfy: A i =-39+10×log10(σ i )+20×log10(f c ) Among them, σ i The corresponding fluctuation model is selected according to the specific simulated combat objectives. is the average RCS value of the simulated target.

5. The radio frequency feature simulation deception method based on one-dimensional range profile according to claim 4, characterized in that: In step S6, the payload receives the real-time attitude angle of the platform, performs coordinate conversion, converts the azimuth angle and the pitch angle into the payload system angle, and obtains the pitch angle tha and the azimuth angle phi.

6. The radio frequency feature simulation deception method based on one-dimensional range profile according to claim 5, characterized in that: In step S7, according to f c Different target data are selected based on the pitch angle tha and the azimuth angle phi. By selecting the target database data and convolving it with the echo data, a one-dimensional distance simulated based on the target data is obtained.

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