Frequency stepping short-range radar high-speed target echo signal equivalent simulation device and method

Abstract

The invention discloses a frequency stepping short-range radar high-speed target echo signal equivalent simulation device and method. The device comprises a data receiving module, a digital intermediate frequency preprocessing module, a speed increasing processing module and a digital-to-analog conversion module. The data receiving module is used for receiving and storing echo signal data of an external field low-speed slide rail test target; the digital intermediate frequency preprocessing module is used for extracting a synchronous detection signal of a short-range radar transmitting signal; an acceleration processing module performs extrapolation and interpolation filtering processing on the external field test low-speed target echo signal according to the simulated high-speed target speed to obtain an accelerated high-speed target echo signal; and the digital-to-analog conversion module realizes the output of a high-speed target echo signal after extrapolation acceleration. According to the invention, high-speed target echoes under the same track are generated through external field low-speed target echo data, corresponding echo signals can be simulated through any high-speed target speed value, and the problem that the high-speed target echoes are difficult to test is solved.

Description

Technical Field

[0001] The invention belongs to the field of radio short-range radar systems, and in particular relates to a device and method for simulating an equivalent simulation of a high-speed target echo signal of a frequency-stepped short-range radar. Background Art

[0002] With the rapid development of electronic technology, modern warfare not only requires radar to complete basic target detection, but also urgently hopes to obtain more target feature information. When missiles detect aerial targets, the means of obtaining refined target feature information is usually a one-dimensional range image. When the radar illuminates the target, when the radar's range resolution unit is much smaller than the radial size of the target, the target occupies multiple range units continuously, which can form a target amplitude image with high and low fluctuations projected on the radar line of sight. The target one-dimensional range image reveals the scattering intensity distribution of the target along the line of sight, reflecting the target scattering feature information. Because the frequency stepped radar has the advantages of high range resolution, good adaptability to high-speed targets, and low signal processing complexity, it has a good application prospect in missile target detection.

[0003] In order to verify the detection performance of frequency-stepped short-range radar for aerial targets, the slide rail test method is currently commonly used. It takes full-scale equipment as the object, uses a carrier to carry the test equipment, and slides along the slide rail at a predetermined speed and acceleration under the action of the power propulsion system to simulate the rendezvous between the missile and the target in the air. Since the slide rail test uses a real target model, the rendezvous posture can also simulate the real rendezvous posture, and the test data has a high reference significance. However, due to the limitation of the running speed of the pulley, the slide rail test cannot realize the rendezvous simulation of high-speed targets. Therefore, how to realize the echo simulation of high-speed targets based on the existing low-speed slide rail real test data needs to be further solved. Summary of the invention

[0004] In order to solve the above problems existing in the prior art, the present invention proposes a device and method for equivalent simulation of high-speed target echo signals of frequency-stepped short-range radar.

[0005] The technical solution to achieve the purpose of the present invention is as follows: In the first aspect, the present invention provides a frequency-stepped short-range radar high-speed target echo signal equivalent simulation device, comprising:

[0006] A data receiving module, used for receiving and storing target echo signal data of an outdoor low-speed slide rail test;

[0007] Digital intermediate frequency preprocessing module, used to extract the synchronous detection signal of the short-range radar transmission signal;

[0008] The speed-increasing processing module is used to perform extrapolation and interpolation filtering on the low-speed target echo signal of the field test according to the simulated high-speed target speed to obtain the high-speed target echo signal after speed increase;

[0009] The digital-to-analog conversion module is used to output high-speed target echo signals after extrapolation and acceleration.

[0010] In a second aspect, the present invention provides a method for equivalent simulation of high-speed target echo signals of a frequency-stepped short-range radar, comprising:

[0011] Receive and store target echo signal data from field low-speed slide rail tests;

[0012] Extract the synchronous detection signal of the short-range radar transmission signal;

[0013] The low-speed target echo signal of the field test is extrapolated and interpolated according to the simulated high-speed target speed to obtain the high-speed target echo signal after speed increase;

[0014] Output the high-speed target echo signal after extrapolation and acceleration.

[0015] In a third aspect, the present invention provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above method when executing the program.

[0016] In a fourth aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, which implements the steps of the above method when executed by a processor.

[0017] Compared with the prior art, the significant advantages of the present invention are as follows: (1) The radar echo simulation device provided by the present invention adopts near-field low-speed motion to simulate high-speed motion, uses the field test data of the low-speed target to obtain the echo signal related to the target azimuth position and performs phase compensation, and uses the speed value of the high-speed motion target to be simulated under the same track condition of the low-speed target, and uses it to perform phase correction on the low-speed echo signal to obtain the high-speed target echo signal; the present invention generates the high-speed target echo under the same track by using the field low-speed target echo data, and can simulate the corresponding echo signal by any high-speed target speed value, thus solving the problem that the high-speed target echo is difficult to test. (2) The current radar echo simulation technology is mainly aimed at the high-speed target echo obtained by modulating the radar transmission signal, while the present invention realizes the simulation of the high-speed target echo signal from the near-field low-speed target echo, retains the information in the actual measurement environment in the data processing, and makes the simulated high-speed target echo closer to the actual measurement data.

[0018] The present invention will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The present invention is an overall system block diagram of a frequency-stepped short-range radar high-speed target echo signal equivalent simulation device.

[0020] Figure 2 The present invention is a block diagram of a data receiving module of a frequency-stepped short-range radar high-speed target echo signal equivalent simulation device.

[0021] Figure 3 The present invention provides a block diagram of a digital intermediate frequency preprocessing module of a frequency-stepped short-range radar high-speed target echo signal equivalent simulation device.

[0022] Figure 4 The present invention is a block diagram of a speed-increasing processing module of a frequency-stepped short-range radar high-speed target echo signal equivalent simulation device. DETAILED DESCRIPTION

[0023] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the present invention.

[0024] like Figure 1 As shown, the present invention proposes a frequency-stepped short-range radar high-speed target echo signal equivalent simulation device, including a data receiving module, a digital intermediate frequency preprocessing module, a speed-increasing processing module and a digital-to-analog conversion module. The data receiving module is used to store the received low-speed data of the external field, and the digital intermediate frequency preprocessing module is used to extract the speed calculation of the echo signal and obtain the synchronous detection signal of the short-range radar transmission signal. The speed-increasing processing module performs extrapolation processing on the low-speed echo signal according to the simulated high-speed target speed, and then performs interpolation filtering processing to finally obtain the echo signal after speed-increasing. The digital-to-analog conversion module is used to play and output the echo signal after speed-increasing.

[0025] Combination Figure 2 The data receiving module includes a network port, a main control module and a storage module. The network port is used to receive the short-range low-speed data of the frequency-stepping radar. The main control module is responsible for controlling the data reception, processing and storage of the equivalent analog device. The memory is used to complete the data storage function.

[0026] Combination Figure 3 The digital intermediate frequency preprocessing module is used to realize the extraction of synchronous detection signal.

[0027] Combination Figure 4 The speed increase processing module is used to implement the phase correction of the starting distance, the calculation of the target modulation information after the speed increase, the phase correction of the first-order speed term, the phase correction of the second-order speed term and the interpolation filtering.

[0028] Preferably, the digital-to-analog conversion module is connected to the speed-up processing module, and is used to output the generated high-speed echo intermediate frequency signal.

[0029] The speed increase processing module of the present invention is described in further detail below.

[0030] The frequency-stepped short-range radar transmit signal and its low-speed echo signal are a group of N related pulses, and the frequency of these pulses increases according to Δf between adjacent pulses.

[0031] The short-range radar transmission signal can be expressed as:

[0032]

[0033] Where f0 is the carrier frequency of the transmitted signal, Δf is the frequency step, n is the current step frequency number, τ is the pulse width, and T is the pulse repetition period;

[0034] Then the target echo signal can be expressed as:

[0035]

[0036] Where c is the speed of light and R is the distance of the target being measured.

[0037] For moving point targets:

[0038] The phase of its echo signal is:

[0039]

[0040] Where R0 is the distance of the target relative to the short-range radar at the beginning of each frame, and v is the radial velocity of the measured target relative to the radar;

[0041] From the perspective of echo simulation, the information required for short-range frequency-stepped radar echo simulation includes: frame synchronization signal and Δf.

[0042] The first term in the phase of the moving point target echo signal is the fixed phase term caused by the initial distance, which can be ignored in the echo simulation; the second term is the phase change caused by the distance and the step frequency, which is temporarily called the distance phase term; the third term is the phase change caused by the target speed, that is, the usual Doppler, which is temporarily called the velocity first-order phase term; the fourth term is the phase change caused by the target speed and the frequency step, which is temporarily called the velocity second-order phase term.

[0043] Assuming that the single target distance of the scattering point is extended to ΔR, the phase difference between the scattering points is 2πΔf2ΔRn / c. This modulation can be multiplied with the scattering point amplitude information and stored in the memory as a target modulation information template.

[0044] For a stationary target, the echo signal phase can be expressed as:

[0045]

[0046] The first term is a fixed phase shift, and the second term is the product of the frequency change rate and the echo delay. In this way, the distance or echo delay is converted into a frequency shift. Therefore, the target distance can be determined by measuring the frequency.

[0047] The frequency measurement can be done by taking the DFT of the received N pulse echoes.

[0048] Compared with directly generating large-bandwidth target echoes, the stepped-frequency high-resolution target echo simulation has a smaller instantaneous bandwidth. However, the processing of the stepped-frequency echo speed increase will make the calculation of the echo phase information more complicated. The calculation of the stepped-frequency echo phase factor requires consideration of the influence of factors such as the initial distance, frequency step amount, target movement speed, and stepped-frequency time.

[0049] The realization of stepped frequency target echo speed increase is to store the low-speed data of the outdoor field first. When the speed is increased, the short-range radar transmits the signal through the receiving link and digital intermediate frequency preprocessing to obtain its synchronous detection signal, which can be used together with the frame synchronization signal to read the search short-range radar number of the stepped frequency specified pulse from the outdoor recorded data.

[0050] The target modulation parameters are calculated based on the target distance, speed and power parameters at different times after the speed increase, and multiplied together with the starting distance phase correction parameters of each frame with the read external low-speed echo pulse signal, and then interpolated and filtered after the speed first phase correction and second phase correction. Finally, the intermediate frequency output of the echo signal after the speed increase is obtained.

[0051] The phase correction of the distance term is implemented by a lookup table, whose input items are

[0052] Among them, Δf is the frequency step; R0 is the distance of the target relative to the short-range radar at the beginning of each frame; n is the current step frequency sequence number; R0 is calculated according to the speed and frame synchronization signal at the beginning of each frame and updated according to the frame period.

[0053] When multi-scattering point information modulation is performed, assuming that the initial distance of the first scattering point is R0, the scattering point spacing is ΔR, and m is the number of scattering points, then the modulation data between the nth PRF scattering points are:

[0054]

[0055] It is calculated by the main control module and multiplied with the scattering point amplitude data.

[0056] The realization of the first-order phase correction of velocity, the modulation is Doppler modulation, The target speed here is the target speed after the increase in speed.

[0057] Where f0 is the carrier frequency of the transmitted signal, v is the radial motion speed of the acceleration target relative to the short-range radar, and c is the speed of light.

[0058] The realization of the speed quadratic phase correction, the search input item of the speed quadratic phase correction is It can be understood as the Doppler frequency deviation caused by frequency stepping, which is Where Δf is the frequency step, v is the radial motion speed of the acceleration target relative to the fuze, and n is the current step frequency sequence number.

[0059] Finally, the echo data processed by speed increase is connected to the digital-to-analog conversion module and output to the measured signal processing system.

[0060] Based on the same inventive concept, the present invention also provides a method for equivalent simulation of high-speed target echo signals of a frequency-stepped short-range radar, which is implemented based on the above-mentioned equivalent simulation device and includes:

[0061] Receive and store target echo signal data from field low-speed slide rail tests;

[0062] Extract the synchronous detection signal of the short-range radar transmission signal;

[0063] The low-speed target echo signal of the field test is extrapolated and interpolated according to the simulated high-speed target speed to obtain the high-speed target echo signal after speed increase;

[0064] Output the high-speed target echo signal after extrapolation and acceleration.

[0065] The specific implementation process of the above method is the same as that of the aforementioned equivalent simulation device, and will not be repeated here.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, rather than to limit it, and the parts not described in detail are common knowledge of ordinary technicians in the field. The protection scope of the present invention shall be based on the content of the claims, and any equivalent changes based on the technical enlightenment of the present invention are also within the protection scope of the present invention.

Claims

1. A frequency-stepped short-range radar high-speed target echo signal equivalent simulation device, characterized in that: include: A data receiving module, used for receiving and storing target echo signal data of an outdoor low-speed slide rail test; Digital intermediate frequency preprocessing module, used to extract the synchronous detection signal of the short-range radar transmission signal; The speed-increasing processing module is used to perform extrapolation and interpolation filtering on the low-speed target echo signal of the field test according to the simulated high-speed target speed to obtain the high-speed target echo signal after speed increase; The digital-to-analog conversion module is used to output high-speed target echo signals after extrapolation and acceleration.

2. The frequency-stepped short-range radar high-speed target echo signal equivalent simulation device according to claim 1 is characterized in that: The data receiving module includes a network port, a main control module and a memory. The network port is used to receive the short-range low-speed data of the frequency-stepping radar. The main control module is responsible for controlling the data reception, processing and storage of the equivalent analog device. The memory is used to complete the data storage function.

3. The frequency-stepped short-range radar high-speed target echo signal equivalent simulation device according to claim 1, characterized in that: The speed increase processing module realizes the phase correction of the starting distance, the calculation of the modulation information of the target after speed increase, the phase correction of the first-order term of speed, the phase correction of the second-order term of speed and the interpolation filtering.

4. The frequency-stepped short-range radar high-speed target echo signal equivalent simulation device according to claim 3 is characterized in that: The frequency-stepped short-range radar transmit signal and its low-speed echo signal are a group of N related pulses, and the frequency of these pulses increases according to Δf between adjacent pulses; The short-range radar transmit signal is expressed as: Where f0 is the carrier frequency of the transmitted signal, Δf is the frequency step, n is the current step frequency number, τ is the pulse width, and T is the pulse repetition period; Then the target echo signal is expressed as: Where c is the speed of light, and R is the distance of the target being measured; For a moving point target, the phase of its echo signal is: Where R0 is the distance of the target relative to the short-range radar at the beginning of each frame, and v is the radial velocity of the measured target relative to the radar; From the perspective of echo simulation, the information required for short-range frequency-stepped radar echo simulation includes: frame synchronization signal, frequency step amount Δf; The first term in the phase of the moving point target echo signal is the fixed phase term caused by the initial distance, which is not considered in the echo simulation; the second term is the phase change caused by the distance and the step frequency, which is called the distance phase term; the third term is the phase change caused by the target speed, which is called the speed first phase term; the fourth term is the phase change caused by the target speed and the frequency step, which is called the speed second phase term; Assuming that the single target distance of the scattering point is extended to ΔR, the phase difference between the scattering points is 2πΔf2ΔRn / c. This modulation is multiplied by the scattering point amplitude information and stored in the memory as the target modulation information template; For a stationary target, the phase of its echo signal is expressed as: The first term is a fixed phase shift, and the second term is the product of the frequency change rate and the echo delay. The distance or echo delay is converted into a frequency shift, and the target distance is determined by measuring the frequency. The frequency measurement is done by taking the DFT of the received N pulse echoes; The realization of step-frequency target echo speed increase is to first store the low-speed data of the field. When speeding up, the short-range radar transmits the signal through the receiving link and digital intermediate frequency preprocessing to obtain its synchronous detection signal, which can be used together with the frame synchronization signal to read the short-range radar number of the step-frequency specified pulse from the field recorded data; The target modulation parameters are calculated based on the target distance, speed and power parameters at different times after the speed increase, and multiplied together with the starting distance phase correction parameters of each frame with the read external low-speed echo pulse signal. After the speed is corrected once and twice, interpolation filtering is performed. Finally, the intermediate frequency output of the echo signal after the speed increase is obtained. The phase correction of the distance term is implemented by a lookup table, whose input items are Wherein, Δf is the frequency step; R0 is the distance of the target relative to the short-range radar at the beginning of each frame; n is the current step frequency sequence number; R0 is calculated according to the speed and frame synchronization signal at the beginning of each frame and updated according to the frame period; When multi-scattering point information modulation is performed, assuming that the initial distance of the first scattering point is R0, the scattering point spacing is ΔR, and m is the number of scattering points, then the modulation data between the nth PRF scattering points are: The main control module calculates and multiplies the data of the scattering point amplitude; The realization of the first-order phase correction of velocity, the modulation is Doppler modulation, The target speed here is the target speed after acceleration; where f0 is the carrier frequency of the transmitted signal, v is the radial motion speed of the accelerated target relative to the short-range radar, and c is the speed of light; The realization of the speed quadratic phase correction, the search input item of the speed quadratic phase correction is Where Δf is the frequency step, v is the radial motion speed of the acceleration target relative to the fuze, and n is the current step frequency sequence number.

5. A method for equivalent simulation of high-speed target echo signals of frequency-stepped short-range radar, characterized in that: include: Receive and store target echo signal data from field low-speed slide rail tests; Extract the synchronous detection signal of the short-range radar transmission signal; The low-speed target echo signal of the field test is extrapolated and interpolated according to the simulated high-speed target speed to obtain the high-speed target echo signal after speed increase; Output the high-speed target echo signal after extrapolation and acceleration.

6. The method according to claim 5, characterized in that The target echo signal data of the outdoor low-speed slide rail test is received and stored through the data receiving module. The data receiving module includes a network port, a main control module and a memory. The network port is used to receive the short-range low-speed data of the frequency-stepping radar, the main control module is responsible for controlling data reception, processing and storage, and the memory is used to complete the data storage function.

7. The method according to claim 5, characterized in that The low-speed target echo signal of the field test is extrapolated and interpolated and filtered according to the simulated high-speed target speed to obtain the high-speed target echo signal after speed increase. Specifically, the speed increase processing module is used to realize the starting distance phase correction, the calculation of the target modulation information after speed increase, the speed first-order phase correction, the speed second-order phase correction and interpolation filtering.

8. The method according to claim 7, characterized in that The frequency-stepped short-range radar transmit signal and its low-speed echo signal are a group of N related pulses, and the frequency of these pulses increases according to Δf between adjacent pulses; The short-range radar transmit signal is expressed as: Where f0 is the carrier frequency of the transmitted signal, Δf is the frequency step, n is the current step frequency number, τ is the pulse width, and T is the pulse repetition period; Then the target echo signal is expressed as: Where c is the speed of light, and R is the distance of the target being measured; For a moving point target, the phase of its echo signal is: Where R0 is the distance of the target relative to the short-range radar at the beginning of each frame, and v is the radial velocity of the measured target relative to the radar; From the perspective of echo simulation, the information required for short-range frequency-stepped radar echo simulation includes: frame synchronization signal, Δf; The first term in the phase of the moving point target echo signal is the fixed phase term caused by the initial distance, which is not considered in the echo simulation; the second term is the phase change caused by the distance and the step frequency, which is called the distance phase term; the third term is the phase change caused by the target speed, which is called the speed first phase term; the fourth term is the phase change caused by the target speed and the frequency step, which is called the speed second phase term; Assuming that the single target distance of the scattering point is extended to ΔR, the phase difference between the scattering points is 2πΔf2ΔRn / c. This modulation is multiplied by the scattering point amplitude information and stored in the memory as the target modulation information template; For a stationary target, the phase of its echo signal is expressed as: The first term is a fixed phase shift, and the second term is the product of the frequency change rate and the echo delay. The distance or echo delay is converted into a frequency shift, and the target distance is determined by measuring the frequency. The frequency measurement is done by taking the DFT of the received N pulse echoes; The realization of step-frequency target echo speed increase is to first store the low-speed data of the field. When speeding up, the short-range radar transmits the signal through the receiving link and digital intermediate frequency preprocessing to obtain its synchronous detection signal, which can be used together with the frame synchronization signal to read the short-range radar number of the step-frequency specified pulse from the field recorded data; The target modulation parameters are calculated based on the target distance, speed and power parameters at different times after the speed increase, and multiplied together with the starting distance phase correction parameters of each frame with the read external low-speed echo pulse signal. After the speed is corrected once and twice, interpolation filtering is performed. Finally, the intermediate frequency output of the echo signal after the speed increase is obtained. The phase correction of the distance term is implemented by a lookup table, whose input items are Wherein, Δf is the frequency step; R0 is the distance of the target relative to the short-range radar at the beginning of each frame; n is the current step frequency sequence number; R0 is calculated according to the speed and frame synchronization signal at the beginning of each frame and updated according to the frame period; When multi-scattering point information modulation is performed, assuming that the initial distance of the first scattering point is R0, the scattering point spacing is ΔR, and m is the number of scattering points, then the modulation data between the nth PRF scattering points are: The main control module calculates and multiplies the data of the scattering point amplitude; The realization of the first-order phase correction of velocity, the modulation is Doppler modulation, The target speed here is the target speed after acceleration; where f0 is the carrier frequency of the transmitted signal, v is the radial motion speed of the accelerated target relative to the short-range radar, and c is the speed of light; The realization of the speed quadratic phase correction, the search input item of the speed quadratic phase correction is Where Δf is the frequency step, v is the radial motion speed of the acceleration target relative to the fuze, and n is the current step frequency sequence number.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the steps of the method according to any one of claims 5 to 8 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the method according to any one of claims 5 to 8 are implemented.

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