Deception interference identification method, device and electronic equipment based on velocity spectrum

Abstract

The present invention belongs to the field of radar technology, and relates to a deception interference identification method, device and electronic device based on speed spectrum. The method includes the following steps: the radar determines the generated Doppler frequency according to the real speed of the real target; the radar transmits a set of broadband pulse signals; samples each pulse signal and performs Fourier transform in the distance dimension; for each distance unit, performs Fourier transform between pulses, and determines the Doppler spectrum of a single distance unit as a speed spectrum; searches for the maximum peak point of the speed spectrum of the current single distance unit; sets the reference value of the maximum peak point as a threshold; counts the number of speed points above the threshold; compares the number of speed points above the threshold with the set threshold, and determines the identification result of the current detection target. The present invention uses broadband signal transmission to identify speed deception interference, and can effectively identify the real target and speed deception interference based on the shape difference between the speed spectrum of the real target and the speed spectrum formed by the deception interference.

Description

Technical Field

[0001] The present invention belongs to the field of radar technology, and in particular, relates to a deception interference identification method, device and electronic equipment based on velocity spectrum. Background Art

[0002] Deception jamming is mainly realized by modern digital radio frequency memory (DRFM) cognitive jammers. DRFM generates modulated original signals, which generate false echo information when the receiver processes the echo signal, reducing the detection probability of the echo signal. Since speed deception jamming and distance deception jamming only exist in one dimension, they have great defects in the face of modern array radars.

[0003] Speed ​​deception jammers use jammers to change the Doppler frequency shift of enemy radar echo signals after receiving radar signals, so that the radar's speed gate tracks the false Doppler frequency and loses the speed deception jammers of the real target. Due to the increase in the number of analog-to-digital sampling bits, the transmitted signal is difficult to distinguish from the real signal, making the signal transmitted by the deception jammer very similar to the actual radar signal, which cannot be effectively distinguished at the radar end, and is then deceived.

[0004] Traditional radars use broadband signal transmission mainly to improve distance resolution. This is not very helpful for identifying deception interference, and it is still difficult to identify whether the signal is real or fake.

[0005] The commonly used method of existing deception jamming is to use distributed multi-base radar for deception jamming identification. The distributed radar deception jamming suppression algorithm mainly includes data-level coordination and signal-level coordination. The data-level deception jamming suppression method can use the multi-dimensional measurement information of the distributed radar on the target to detect the spatial correlation difference between the real target and the false target in speed, angle or position, and perform point or track association to identify the real and false targets. Because the target information is not limited to speed, angle and distance information, but also includes the target echo information, and the amplitude information of the target echo is lost during data-level fusion, resulting in serious information loss. Multi-base radar has great application limitations in practical applications, the cost increases too much, and the accuracy of identifying jamming also depends on the configuration of the distributed radar. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides a deception interference identification method, device and electronic equipment based on velocity spectrum.

[0007] In a first aspect, the present invention provides a deception interference identification method based on velocity spectrum, comprising:

[0008] Determine the generated Doppler frequency based on the real speed of the real target;

[0009] Transmitting a set of broadband pulse signals;

[0010] Each pulse signal is sampled and Fourier transformed in the distance dimension;

[0011] For each range unit, Fourier transform is performed between pulses to determine the Doppler spectrum of a single range unit as the velocity spectrum;

[0012] Search for the maximum peak point of the velocity spectrum of the current single distance unit;

[0013] Set the reference value of the maximum peak point as the threshold;

[0014] Count the speed points above the threshold;

[0015] The number of speed points above the threshold is compared with the set threshold to determine the recognition result of the current detection target.

[0016] In a second aspect, the present invention provides a deception interference identification device based on a velocity spectrum, comprising a first processing unit, a transmitting unit, a sampling processing unit, a second processing unit, a searching unit, a setting unit, a statistical unit and a comparing unit;

[0017] A first processing unit is used to determine the generated Doppler frequency according to the real speed of the real target;

[0018] The transmitting unit is used for the radar to transmit a set of broadband pulse signals;

[0019] A sampling processing unit, used for sampling each pulse signal and performing Fourier transform in the distance dimension;

[0020] A second processing unit is used for performing Fourier transform between pulses for each range unit to determine a Doppler spectrum of a single range unit as a velocity spectrum;

[0021] A search unit, used to search for the maximum peak point of the velocity spectrum of the current single distance unit;

[0022] A setting unit, used to set a reference value of a maximum peak point as a threshold;

[0023] A statistics unit, used to count the speed points above the threshold;

[0024] The comparison unit is used to compare the number of speed points above the threshold with the set threshold to determine the recognition result of the current detection target.

[0025] In a third aspect, the present invention provides an electronic device, comprising:

[0026] Processor and memory;

[0027] The memory is used to store computer operation instructions;

[0028] The processor is used to execute the deception interference identification method based on speed spectrum by calling the computer operation instruction.

[0029] Based on the above technical solution, the present invention can also be improved as follows.

[0030] Furthermore, when the radar signal received by the deception jammer is a linear frequency modulation signal, is the starting frequency of the linear frequency modulation signal, and the signal bandwidth is , the pulse width is , is the frequency modulation slope, , For time, is the imaginary number symbol, then:

[0031] .

[0032] Furthermore, for the deception jammer, let the speed to be simulated be , is the wavelength and the Doppler frequency is ,but:

[0033] ;

[0034] Assume the radar pulse repetition period is , in the radar pulse repetition period When the jammer has acquired the virtual phase between each pulse, the phase is expressed as an arithmetic sequence, the initial phase is 0, and the difference of the arithmetic sequence is expressed as ;

[0035] is the starting frequency of the linear frequency modulation signal, and the signal bandwidth is , the frequency range of the radar transmission signal is , the maximum frequency is expressed as , let the wavelength corresponding to the maximum frequency bandwidth signal be , the wavelength corresponding to the minimum frequency bandwidth signal is ,but:

[0036] ;

[0037] .

[0038] Furthermore, for a real target, let the real speed be , the Doppler frequency generated by the maximum frequency bandwidth signal is , the Doppler frequency generated by the minimum frequency bandwidth signal is ,but:

[0039] ;

[0040] ;

[0041] Assume that the phase of the superimposed maximum frequency bandwidth signal waveform is , the phase of the superposition of the minimum frequency bandwidth signal waveform is ,but:

[0042] ;

[0043] .

[0044] Furthermore, 1 / 2 of the maximum peak point is set as the threshold.

[0045] Furthermore, the number of speed points above the threshold is compared with the set threshold. If the number of speed points above the threshold is greater than the set threshold, the recognition result of the current detection target is a deceptive interference signal, otherwise the recognition result of the current detection target is a real target.

[0046] The beneficial effects of the present invention are as follows: the present invention adopts a broadband signal transmission method to identify speed deception interference, and the shape difference between the speed spectrum of the real target and the speed spectrum formed by the deception interference can effectively identify the real target and the speed deception interference. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 The deception interference identification method based on velocity spectrum provided in Embodiment 1 of the present invention;

[0048] Figure 2 is the relationship between instantaneous frequency and time;

[0049] Figure 3 It is the LFM signal frequency variation curve;

[0050] Figure 4 Doppler spectrum of deceptive jammers and real signals with a bandwidth of 2 GHz;

[0051] Figure 5 Doppler spectrum of deceptive jammers and real signals with a bandwidth of 100MHz;

[0052] Figure 6 A schematic diagram of a deception interference identification device based on velocity spectrum provided in Embodiment 1 of the present invention;

[0053] Figure 7 This is a schematic diagram of an electronic device provided in Example 3 of the present invention.

[0054] Icons: 30 - electronic device; 310 - processor; 320 - bus; 330 - memory; 340 - transceiver. DETAILED DESCRIPTION

[0055] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0056] Example 1

[0057] As an example, Figure 1 As shown, in order to solve the above technical problems, this embodiment provides a deception interference identification method based on velocity spectrum, including:

[0058] Determine the generated Doppler frequency based on the real speed of the real target;

[0059] Transmitting a set of broadband pulse signals;

[0060] Each pulse signal is sampled and Fourier transformed in the distance dimension;

[0061] For each range unit, Fourier transform is performed between pulses to determine the Doppler spectrum of a single range unit as the velocity spectrum;

[0062] Search for the maximum peak point of the velocity spectrum of the current single distance unit;

[0063] Set the reference value of the maximum peak point as the threshold;

[0064] Count the speed points above the threshold;

[0065] The number of speed points above the threshold is compared with the set threshold to determine the recognition result of the current detection target.

[0066] In practical applications, linear frequency modulation (LFM) signals are commonly used broadband signal sources for radar. Assume that for a single frequency signal , the angular frequency is , is a constant, and for an LMF signal, the angular frequency is , is the starting angular frequency, is the FM speed, is the bandwidth, is the pulse duration, is the starting frequency of the linear frequency modulation signal, then:

[0067] .

[0068] Instantaneous frequency With time The relationship is as follows Figure 2 As shown. The phase of ,but:

[0069] .

[0070] The linear frequency modulation signal is expressed as .

[0071] When the radar signal received by the deception jammer is a linear frequency modulation signal, is the starting frequency of the linear frequency modulation signal, and the signal bandwidth is , the pulse width is , is the frequency modulation slope, , For time, is the imaginary number symbol, then:

[0072] .

[0073] For the deception jammer, let the speed to be simulated be , is the wavelength and the Doppler frequency is ,but:

[0074] ;

[0075] Assume the radar pulse repetition period is , in the radar pulse repetition period When the jammer has acquired the virtual phase between each pulse, the phase is expressed as an arithmetic sequence, the initial phase is 0, and the difference of the arithmetic sequence is expressed as ; as attached Figure 3 The LFM signal frequency variation curve is shown in Figure 1, and pulse M1 is represented by , pulse M2 is expressed as , pulse M3 is expressed as .

[0076] is the starting frequency of the linear frequency modulation signal, and the signal bandwidth is , the frequency range of the radar transmission signal is , the maximum frequency is expressed as , let the wavelength corresponding to the maximum frequency bandwidth signal be , the wavelength corresponding to the minimum frequency bandwidth signal is ,but:

[0077] ;

[0078] .

[0079] For a real target, let the real speed be , the Doppler frequency generated by the maximum frequency bandwidth signal is , the Doppler frequency generated by the minimum frequency bandwidth signal is ,but:

[0080] ;

[0081] ;

[0082] Assume that the phase of the superimposed maximum frequency bandwidth signal waveform is , the phase of the superposition of the minimum frequency bandwidth signal waveform is ,but:

[0083] ;

[0084] .

[0085] Assuming the frequency range is 10-12 GHz, the target's real speed is 100 m / s, and the number of coherent pulses is 256, the simulation diagram of the deceptive interference and the real signal (wideband signal - bandwidth 2 GHz) is as shown in the attached figure. Figure 4 As shown in the figure, L41 is a real signal with a broadband signal bandwidth of 100MHz, and L42 is a deceptive interference signal. Figure 5 As shown, L51 is a real signal with a broadband signal bandwidth of 100 MHz, L52 is a deception interference signal, the horizontal axis is the Doppler number, and the vertical axis is the amplitude.

[0086] Optionally, set 1 / 2 of the maximum peak point as the threshold.

[0087] The present invention sets the threshold at 1 / 2 of the maximum value in the threshold setting. In practical applications, the threshold can be set as needed and is affected by the bandwidth of the transmitted signal. The threshold can be set according to the actual situation.

[0088] Optionally, the number of speed points above the threshold is compared with a set threshold. If the number of speed points above the threshold is greater than the set threshold, the recognition result of the current detection target is a deceptive interference signal, otherwise the recognition result of the current detection target is a real target.

[0089] The specific speed deception interference identification process is as follows:

[0090] Transmitting a set of broadband pulse signals;

[0091] Each pulse is sampled and Fourier transformed in the distance dimension, i.e., FFT processing;

[0092] Step 3: For each range unit, perform FFT processing between pulses to obtain the Doppler spectrum of a single range unit or velocity spectrum;

[0093] Search for the maximum peak point of the velocity spectrum of the current distance unit;

[0094] Set 1 / 2 of the maximum peak point as the threshold;

[0095] Count the speed points above the threshold;

[0096] If the number of speed points above the threshold is greater than 5, the current detection target is a deception interference; if it is less than 5, the detection target is a real target.

[0097] Since the wavelengths of different frequency signals are different, the Doppler frequencies and superimposed phases formed will be different, and the deception jammer only superimposes a phase on the received echo signal, which cannot meet the requirement of superimposing phases of different frequency signals separately. The present invention uses broadband signal transmission to identify speed deception jamming, based on the fact that the real target speed spectrum has a certain width, while the speed spectrum forged by the deception jamming is narrower, and the shape difference between the speed spectrum of the real target and the speed spectrum formed by the deception jamming can effectively identify the real target and the speed deception jamming.

[0098] The velocity spectrum of the real target or the phase value between pulses is related to the real speed of the target, and is also related to the carrier frequency or wavelength of the currently transmitted radar signal. When the signal emitted by the radar is a narrowband signal, the frequency range is very small, and the phase values ​​formed for different frequencies are extremely similar. When the deception interference forges a set of phase values, a velocity spectrum similar to that of the real target can be formed. When the signal emitted by the radar is a broadband signal, the frequency range is large, and the phase values ​​formed for different frequencies are extremely different. There will be a significant difference between the real target and the deception interference. The present invention uses this feature to identify speed deception interference. Traditional radars use broadband waveform transmission only to improve the range resolution of the radar. However, improving the range resolution of the radar cannot directly improve the radar's ability to identify speed deception interference.

[0099] Example 2

[0100] Based on the same principle as the method shown in Example 1 of the present invention, as shown in the attached Figure 6As shown, an embodiment of the present invention also provides a deception interference identification device based on a velocity spectrum, comprising a first processing unit, a transmitting unit, a sampling processing unit, a second processing unit, a searching unit, a setting unit, a statistical unit and a comparing unit;

[0101] A first processing unit is used to determine the generated Doppler frequency according to the real speed of the real target;

[0102] The transmitting unit is used for the radar to transmit a set of broadband pulse signals;

[0103] A sampling processing unit, used for sampling each pulse signal and performing Fourier transform in the distance dimension;

[0104] A second processing unit is used for performing Fourier transform between pulses for each range unit to determine a Doppler spectrum of a single range unit as a velocity spectrum;

[0105] A search unit, used to search for the maximum peak point of the velocity spectrum of the current single distance unit;

[0106] A setting unit, used to set a reference value of a maximum peak point as a threshold;

[0107] A statistics unit, used to count the speed points above the threshold;

[0108] The comparison unit is used to compare the number of speed points above the threshold with the set threshold to determine the recognition result of the current detection target.

[0109] Optionally, when the radar signal received by the deception jammer is a linear frequency modulation signal, set is the starting frequency of the linear frequency modulation signal, and the signal bandwidth is , the pulse width is , is the frequency modulation slope, , For time, is the imaginary number symbol, then:

[0110] .

[0111] Optionally, for a deception jammer, let the speed to be simulated be , is the wavelength and the Doppler frequency is ,but:

[0112] ;

[0113] Assume the radar pulse repetition period is , in the radar pulse repetition period When the jammer has acquired the virtual phase between each pulse, the phase is expressed as an arithmetic sequence, the initial phase is 0, and the difference of the arithmetic sequence is expressed as ;

[0114] is the starting frequency of the linear frequency modulation signal, and the signal bandwidth is , the frequency range of the radar transmission signal is , the maximum frequency is expressed as , let the wavelength corresponding to the maximum frequency bandwidth signal be , the wavelength corresponding to the minimum frequency bandwidth signal is ,but:

[0115] ;

[0116] .

[0117] Optionally, for a real target, let the real speed be , the Doppler frequency generated by the maximum frequency bandwidth signal is , the Doppler frequency generated by the minimum frequency bandwidth signal is ,but:

[0118] ;

[0119] ;

[0120] Assume that the phase of the superimposed maximum frequency bandwidth signal waveform is , the phase of the superposition of the minimum frequency bandwidth signal waveform is ,but:

[0121] ;

[0122] .

[0123] Optionally, set 1 / 2 of the maximum peak point as the threshold.

[0124] Optionally, the number of speed points above the threshold is compared with a set threshold. If the number of speed points above the threshold is greater than the set threshold, the recognition result of the current detection target is a deceptive interference signal, otherwise the recognition result of the current detection target is a real target.

[0125] Example 3

[0126] Based on the same principle as the method shown in the embodiment of the present invention, an electronic device is also provided in the embodiment of the present invention, as shown in the attached Figure 7As shown, the electronic device may include but is not limited to: a processor and a memory; the memory is used to store a computer program; the processor is used to execute the deception interference identification method based on speed spectrum shown in the embodiment of the present invention by calling the computer program.

[0127] In an optional embodiment, an electronic device is provided. Figure 7 The electronic device 30 shown includes: a processor 310 and a memory 330. The processor 310 and the memory 330 are connected, for example, via a bus 320.

[0128] Optionally, the electronic device 30 may further include a transceiver 340, which may be used for data interaction between the electronic device and other electronic devices, such as data transmission and / or data reception. It should be noted that in actual applications, the transceiver 340 is not limited to one, and the structure of the electronic device 30 does not constitute a limitation on the embodiments of the present invention.

[0129] The processor 310 may be a CPU (Central Processing Unit), a general-purpose processor, a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. It may implement or execute various exemplary logic blocks, modules and circuits described in conjunction with the disclosure of the present invention. The processor 310 may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, etc.

[0130] The bus 320 may include a path to transmit information between the above components. The bus 320 may be a PCI (Peripheral Component Interconnect) bus or an EISA (Extended Industry Standard Architecture) bus. The bus 320 may be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 7 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0131] The memory 330 can be a ROM (Read Only Memory) or other types of static storage devices that can store static information and instructions, a RAM (Random Access Memory) or other types of dynamic storage devices that can store information and instructions, or an EEPROM (Electrically Erasable Programmable Read Only Memory), a CD-ROM (Compact Disc Read Only Memory) or other optical disk storage, optical disk storage (including compressed optical disk, laser disk, optical disk, digital versatile disk, Blu-ray disk, etc.), a magnetic disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited to these.

[0132] The memory 330 is used to store application code (computer program) for executing the solution of the present invention, and is controlled to be executed by the processor 310. The processor 310 is used to execute the application code stored in the memory 330 to implement the contents shown in the above method embodiment.

[0133] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A deception jamming identification method based on velocity spectrum, characterized in that: include: Determine the generated Doppler frequency based on the real speed of the real target; Transmitting a set of broadband pulse signals; Each pulse signal is sampled and Fourier transformed in the distance dimension; For each range unit, Fourier transform is performed between pulses to determine the Doppler spectrum of a single range unit as the velocity spectrum; Search for the maximum peak point of the velocity spectrum of the current single distance unit; Set the reference value of the maximum peak point as the threshold; Count the speed points above the threshold; The number of speed points above the threshold is compared with the set threshold to determine the recognition result of the current detection target.

2. The deception jamming identification method based on velocity spectrum according to claim 1 is characterized in that: When the radar signal received by the deception jammer is a linear frequency modulation signal, is the starting frequency of the linear frequency modulation signal, and the signal bandwidth is , the pulse width is , is the frequency modulation slope, , For time, is the imaginary number symbol, then: 。 3. The deception interference identification method based on velocity spectrum according to claim 2 is characterized in that: For the deception jammer, let the speed to be simulated be , is the wavelength and the Doppler frequency is ,but: ； Assume the radar pulse repetition period is , in the radar pulse repetition period When the jammer has acquired the virtual phase between each pulse, the phase is expressed as an arithmetic sequence, the initial phase is 0, and the difference of the arithmetic sequence is expressed as ; is the starting frequency of the linear frequency modulation signal, and the signal bandwidth is , the frequency range of the radar transmission signal is , the maximum frequency is expressed as , let the wavelength corresponding to the maximum frequency bandwidth signal be , the wavelength corresponding to the minimum frequency bandwidth signal is ,but: ； 。 4. The deception jamming identification method based on velocity spectrum according to claim 3 is characterized in that: For a real target, let the real speed be , the Doppler frequency generated by the maximum frequency bandwidth signal is , the Doppler frequency generated by the minimum frequency bandwidth signal is ,but: ； ； Assume that the phase of the superimposed maximum frequency bandwidth signal waveform is , the phase of the superposition of the minimum frequency bandwidth signal waveform is ,but: ； 。 5. The deception jamming identification method based on velocity spectrum according to claim 1 is characterized in that: Set 1 / 2 of the maximum peak point as the threshold.

6. The deception jamming identification method based on velocity spectrum according to claim 1 is characterized in that: The number of speed points above the threshold is compared with the set threshold. If the number of speed points above the threshold is greater than the set threshold, the recognition result of the current detection target is a deceptive interference signal, otherwise the recognition result of the current detection target is a real target.

7. A deception jamming identification device based on velocity spectrum, characterized in that: It includes a first processing unit, a transmitting unit, a sampling processing unit, a second processing unit, a searching unit, a setting unit, a statistical unit and a comparing unit; A first processing unit is used to determine the generated Doppler frequency according to the real speed of the real target; The transmitting unit is used for the radar to transmit a set of broadband pulse signals; A sampling processing unit, used for sampling each pulse signal and performing Fourier transform in the distance dimension; A second processing unit is used for performing Fourier transform between pulses for each range unit to determine a Doppler spectrum of a single range unit as a velocity spectrum; A search unit, used to search for the maximum peak point of the velocity spectrum of the current single distance unit; A setting unit, used to set a reference value of a maximum peak point as a threshold; A statistics unit, used to count the speed points above the threshold; The comparison unit is used to compare the number of speed points above the threshold with the set threshold to determine the recognition result of the current detection target.

8. An electronic device, characterized in that: include: Processor and memory; The memory is used to store computer operation instructions; The processor is used to execute the deception interference identification method based on velocity spectrum according to any one of claims 1 to 6 by calling the computer operation instructions.

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