A method for simulating high-speed mobile platform guided flight using a SAR radar mounted on a track system

Abstract

The present invention relates to a method for simulating guided flight of a high-speed mobile platform by mounting a SAR radar on a track system. The method comprises the following steps: S0 constructing a scene model sand table and a guided flight simulation system, wherein the guided flight simulation system comprises a track system, a servo turntable system, and a radar system for simulating the guided flight process of the high-speed mobile platform; S1 controlling the servo turntable system to move the radar system along the track system according to a set moving distance and moving speed, while simultaneously collecting range-azimuth two-dimensional echo data of scattering point targets on the scene model sand table; S2 performing imaging processing on the range-azimuth two-dimensional echo data to obtain an echo imaging map; and S3 performing image matching and distance registration on the echo imaging map with a preset prior optical map. The present invention can achieve a highly realistic simulation of a high-speed mobile platform using synthetic aperture radar for guided flight.

Description

Technical Field

[0001] The present invention relates to the technical field of high-speed mobile platform guidance simulation, in particular to a method for simulating high-speed mobile platform guided flight by mounting a SAR radar on a track system. Background Art

[0002] When verifying the guidance performance of a newly developed high-speed maneuvering platform mounted with a synthetic aperture radar (SAR), or verifying the SAR's operating modes under different guidance modes, it is necessary to theoretically verify the feasibility of the equipment before conducting a live-fire guided strike against a set target. Currently, helicopters are often used to perform level and dive maneuvers while carrying a SAR to simulate the SAR guidance workflow of a high-speed maneuvering platform in different flight phases. This means that the helicopter's flight trajectory is used to simulate the high-speed maneuvering platform's flight trajectory and verify the SAR's guidance performance under different operating modes. However, using a helicopter instead of a high-speed maneuvering platform to simulate its flight trajectory presents some unavoidable problems. First, due to the difference in flight speed between the high-speed maneuvering platform and the helicopter, the helicopter's flight speed ranges from 240 to 310 kilometers per hour, while the missile's flight speed is generally around Mach 4 to 5 (Mach 1 is equivalent to 1225 kilometers per hour). Therefore, the difference in the payload platform's movement speed will cause distortion in the azimuth sampling of the synthetic aperture radar during echo data processing, which poses problems for verifying the feasibility of the high-speed maneuvering platform. Second, due to the difference in the helicopter's aerodynamic shape and the high-speed maneuvering platform's movement posture, the helicopter may not be as flexible in changing the roll angle and pitch angle as the high-speed maneuvering platform, which will also affect the radar fitting accuracy of the synthetic aperture radar during live-fire guidance. Finally, due to the difference in flight altitude between the high-speed maneuvering platform and the helicopter, the radar imaging process will suffer from geometric proportional distortion in the simulation of the working modes such as the straight side view and oblique forward view, which will affect the subsequent echo data imaging processing algorithm. In addition, since the synthetic aperture radar hardware mounted on the helicopter is in the test and verification stage, the robustness of its radar performance is relatively low, and it is necessary to use the helicopter to repeatedly conduct leveling and dive maneuver tests, which still results in certain consumption in the verification cost, such as the consumption of helicopter flight resources, the coordination of debugging personnel and the occupation of airspace. In addition, the test of synthetic aperture radar hardware equipment mounted on the helicopter is not conducive to scientific researchers to adjust and modify the synthetic aperture radar hardware parameters in real time. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a method for simulating the guided flight of a high-speed mobile platform by mounting a SAR radar on a track system. The method can eliminate the problems of geometric configuration distortion, azimuth echo data processing and scanning beam flexibility existing in the traditional application of a helicopter-mounted synthetic aperture radar to simulate and verify the synthetic aperture radar mounted on a high-speed mobile platform, avoid the negative impact when verifying the guidance performance of a newly developed synthetic aperture radar mounted on a high-speed mobile platform or when verifying the working mode of the synthetic aperture radar under different guidance modes, and realize a high-fidelity simulation of the synthetic aperture radar-guided flight of a high-speed mobile platform.

[0004] The technical solution adopted by the present invention to solve the technical problem is to provide a method for simulating high-speed mobile platform guided flight by mounting SAR radar on a track system, comprising:

[0005] S0 builds a scene model sandbox and a guided flight simulation system, wherein the guided flight simulation system includes a track system, a servo turntable system, and a radar system, and is used to simulate the guided flight process of a high-speed mobile platform;

[0006] S1 controls the servo turntable system to move the radar system along the track system according to the set moving distance and moving speed, while collecting the range-azimuth two-dimensional echo data of the scattering point targets on the scene model sand table;

[0007] S2 performs imaging processing on the range-azimuth two-dimensional echo data to obtain an echo imaging image;

[0008] S3 performs image matching and distance registration on the echo imaging image and the preset prior optical image.

[0009] Furthermore, the collecting of range-azimuth two-dimensional echo data of scattering point targets on the scene model sandbox includes:

[0010] Calculate the azimuth dimension time quantity according to the moving distance and moving speed of the radar system and the radar pulse repetition interval of the radar system;

[0011] Calculate the slant range from the scattering point target on the scene model sandbox to the radar system based on the operating altitude and moving speed of the radar system at the current azimuth moment;

[0012] Traversing the azimuth dimension time, calculating the slant range history of all the scattering point targets to the radar system as phase history two-dimensional data;

[0013] After performing pulse compression processing on the phase history two-dimensional data in the range dimension and data accumulation processing on the azimuth dimension, the range-azimuth two-dimensional echo data of the scattering point target are extracted from the obtained two-dimensional impulse function matrix.

[0014] Furthermore, the pulse compression processing of the two-dimensional phase history data in the distance dimension is achieved by de-linear frequency modulation.

[0015] Furthermore, the track system includes a first track and a second track for simulating the horizontal autonomous cruise maneuvering segment and the downward dive flight maneuvering segment in the missile flight trajectory respectively.

[0016] Furthermore, before step S1, the method further includes the step of setting parameters of the servo turntable system, specifically including:

[0017] Set whether to perform scanning action;

[0018] Set the scanning angle of the radar system when operating in the first and second orbits respectively.

[0019] Furthermore, before step S1, the method further includes the step of setting parameters of the radar system, including setting the pulse width and signal bandwidth of the radar signal.

[0020] Furthermore, before step S1, the method further includes a step of aligning the timestamp of the radar transmission signal with the time when the radar system starts to move.

[0021] Furthermore, before step S2, the method further includes the steps of sequentially performing high-pass filtering on the range-azimuth two-dimensional echo data and recovering target characteristic phase information.

[0022] Furthermore, the scene model sandbox is within the beam range of the first radar system.

[0023] Furthermore, the guided flight simulation system is constructed by the following method:

[0024] Obtaining the flight trajectory of the high-speed mobile platform to be simulated during the guided flight process;

[0025] A track system is constructed to simulate the flight trajectory, and a radar system and a servo turntable system are mounted on the track system to respectively simulate the radar system and antenna servo mechanical system mounted on the high-speed mobile platform.

[0026] Beneficial effects

[0027] Due to the adoption of the above-mentioned technical solution, the present invention has the following advantages and positive effects compared with the prior art: the present invention simplifies the actual field verification test into actual echo signal data processing and guidance theory verification through the principle of geometric scaling, and solves the problem of limited simulation fitting when a helicopter-mounted synthetic aperture radar simulates the guided flight of an actual high-speed mobile platform in principle, reduces the need for the helicopter to perform repeated leveling and dive maneuvers, reduces the consumption of flight resources, and reduces the experimental verification costs of debugging personnel and airspace occupation. The simulation of the guided flight process of the high-speed mobile platform is clear and concise, which effectively enhances the learning efficiency of beginners. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 Schematic diagram of an experimental scenario of an embodiment of the present invention;

[0029] Figure 2 is a schematic diagram of a mobile platform according to an embodiment of the present invention;

[0030] Figure 3 is a schematic diagram of a mounting servo turntable system according to an embodiment of the present invention;

[0031] Figure 4 1 is a schematic diagram of the operation of a positive side-looking imaging radar according to an embodiment of the present invention;

[0032] Figure 5 It is a schematic diagram of the experimental process of an embodiment of the present invention. DETAILED DESCRIPTION

[0033] Below in conjunction with specific embodiment, further set forth the present invention.Should be understood that these embodiments are only used to illustrate the present invention and are not used in limiting the scope of the present invention.In addition, should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall equally within the scope limited by the appended claims of the application.

[0034] The present invention relates to a method for simulating guided flight using a high-speed mobile platform mounted with a synthetic aperture radar using a scaled indoor trajectory model. This method can achieve a highly realistic simulation of a high-speed mobile platform using synthetic aperture radar guidance. Specifically, under scaled indoor environmental conditions, the method simulates a high-speed mobile platform mounted with a synthetic aperture radar guiding flight against a target in an actual interactive battlefield with high fidelity and high fit from the perspectives of theoretical verification of geometric configuration, actual echo generation, and imaging through processing of measured data. The specific technical solution is as follows:

[0035] Determine the approximate route planning during the high-speed mobile platform guided flight that needs to be simulated, including the launch climb phase, the horizontal autonomous cruise maneuver phase, and the downward dive flight maneuver phase.

[0036] Components are replaced according to the relevant modules required for verification of high-speed mobile platform guided flight, the missile flight trajectory is simulated using an indoor fixed track system, the antenna servo mechanical system of the mounted synthetic aperture radar is simulated using a three-axis servo turntable, and the mounted synthetic aperture radar is replaced with a miniSAR radar with lower radiation power.

[0037] Design the indoor fixed track system's height and distance for the level flight phase, the height and distance for the descent phase, the servo turntable's downward viewing angle range for the front and side views (scanning), the forward oblique viewing angle range, and the descent scanning servo turntable's rotation range and speed;

[0038] The track system, servo turntable system and synthetic aperture radar system were built indoors. In order to achieve a high-fidelity simulation effect, a sand table simulating mountain, city and desert scene models was built indoors. At the same time, it was calculated whether the designed geometric configuration was proportionally consistent with the geometric configuration of the high-speed mobile platform mounted with synthetic aperture radar for open-mechanism guided flight in actual combat.

[0039] Plan the horizontal flight path (horizontal segment) of the simulated high-speed mobile platform, and set its length as L hor , calculate the moving distance r of the simulated high-speed mobile platform on the track system at each moment hor , moving speed v hor , operating height h hor :

[0040] Plan the downward flight path (downward flight path) of the simulated high-speed mobile platform, and set its length as L dec Calculate the moving distance r of the simulated high-speed mobile platform on the track system at each moment dec , moving speed v dec , operating height h dec :

[0041] Plan the parameters of the synthetic aperture radar mounted on a simulated high-speed mobile platform, including signal bandwidth B r , pulse width T p , signal modulation frequency γ, signal carrier frequency f c , pulse repetition frequency PRF, distance dimension sampling frequency f r and radar antenna azimuth θ azi / pitch angle θ ran The signal waveform of the radar is a linear frequency modulation signal, and the carrier frequency of the signal is e j2πfct , t is the full time including the slow time t a (azimuth time) and fast time t r (distance to time) two categories, t = t a +t r ;

[0042] Plan the parameters of the servo turntable mounted on the simulated high-speed mobile platform, including the lower viewing angle θ in the front and side view (scanning) mode down 、The lower viewing angle θ in the front strabismus mode down and the oblique angle θ slant Angle size, angular velocity ω in scanning mode r and the rotation angle range θ cir Waiting for parameter information to be issued:

[0043] After setting the parameters of the track system, servo system and synthetic aperture radar system, the simulated high-speed mobile platform mounted synthetic aperture radar at a certain azimuth time t can be obtained. azi (i) The obtained two-dimensional original echo data matrix M of the measured range-azimuth dimension r×a ,At the same time, a three-dimensional space coordinate axis O-XYZ is established based on the middle position of the horizontal section of the indoor track system;

[0044] Taking the level flight segment as an example, for any azimuth slowing time t azi (i) According to the height H of the synthetic aperture radar mounted on the simulated high-speed mobile platform radar (t azi ) (ignore the mounting distance between the synthetic aperture radar and the payload platform at this time) and a certain scattering point target P(x tar ,y tar ,z tar ), the 3D distance method is used to solve the slant range history R of the synthetic aperture radar from the scattering point target P i , its formula is:

[0045]

[0046] From the moment when the synthetic aperture radar starts working to the moment when the synthetic aperture radar ends collecting data, the azimuth dimension accumulation time t azi (i) By calculating the slant range history R from the ground scattering point to the synthetic aperture radar i It can be obtained that the slope distance history R i The phase history φ required for imaging processing i There is a relationship. By performing pulse compression processing on the two-dimensional phase history data in the distance dimension and data accumulation processing in the azimuth dimension, a two-dimensional impact function matrix containing the set scattering points can be obtained.

[0047] In order to better fit the actual working mode of synthetic aperture radar, it is necessary to analyze the working mode of the mounted synthetic aperture radar. Here we use strip type positive side imaging for analysis. Since the orbit height of the indoor orbit model system determines h hor And combined with the viewing angle θdown and the pitch angle θ ran , therefore, the projection area R of its radar beam on the ground zoom It is determined, and its formula can be expressed as:

[0048] R zoom =h hor tan(θ down +θ ran / 2)-h hor tan(θ down -θ ran / 2);

[0049] To process the recorded radar echoes and perform imaging on them, the sand table model needs to be placed within the radar beam range. In order to improve the simulation fit, a corner reflector model can be appropriately placed within the beam range.

[0050] When synthetic aperture radar transmits a signal, it first generates a baseband signal And perform digital up-conversion on the baseband signal, that is, add the carrier frequency f c The main purpose is to reduce the size of the transmitting antenna to facilitate lightweight integration of the device. After the LFM signal is formed, it is transmitted by the antenna. The mathematical expression of the transmitted signal can be written as:

[0051]

[0052] A r (t a ) is a commonly used rectangular gate distance dimension window function representation, which can be expressed as:

[0053]

[0054] Then, after the receiving antenna receives the echo signal, it performs down-conversion processing on the echo signal (also often called carrier removal). The expression of the echo signal can be written as:

[0055]

[0056] Same formula A r (t a ), A a (t a ) is the azimuth window function, and δ i The scattering coefficient of a scattering point in the scene is related to the antenna pattern of the receiving antenna.

[0057] In the above formula, 2R(t a ; R Di ) / c represents the time delay τ from the time the transmitted signal is transmitted to the time it is reflected by the target and then received by the receiving antenna;

[0058] and They represent the baseband signal phase delay and the azimuth phase after carrier frequency removal reception respectively.

[0059] Ideally, the attenuation of the echo signal due to the multipath effect in the spatial transmission process is ignored, and the azimuth window function is set to a rectangular window, just like the range-dimension rectangular window function.

[0060] By calculation, the echo time domain signal model expression of the LFM signal in the range-azimuth two-dimensional section can be obtained as follows:

[0061]

[0062] In the above expression Expressed as the phase envelope of the scattering point signal;

[0063] After obtaining the above echo signals, we can obtain the original two-dimensional echo data containing the simulated sandbox scene. Then, we need to perform imaging processing on the echo signals: range-dimensional pulse compression. There are two practical forms of pulse compression: matched filtering and dechirping. To better match the pulse compression method used by synthetic aperture radar in actual engineering, we use dechirp, which is more widely used in engineering.

[0064] De-modulation is a pulse compression method suitable for small scenarios. Its main advantage is that when processing large-bandwidth signals, the calculation processing is relatively simple, which can simplify the calculation operation and reduce the hardware cost of the equipment.

[0065] The linear frequency modulation method is the same as the matched filtering method. Both methods require the selection of a suitable reference signal, but the form of the reference signal is different. The linear frequency modulation method requires the selection of a reference slant distance R ref To construct the signal, the signal can be expressed as:

[0066]

[0067] The above formula is the reference signal composition in the constructed Dechirp operation. In fact, it is essentially similar to the matched filter operation. The main difference is the setting of the reference slant range. By combining the linear frequency modulation echo signal with the reference slant range signal s ref (t,f n ) after Dechirp processing to obtain the difference frequency echo signal s if (t,f n ) can be expressed as:

[0068]

[0069] The echo signal after range-dimension difference frequency reception can be obtained as:

[0070]

[0071] γ=Δf / t0 is the frequency modulation rate contained in the linear frequency modulation signal, which represents the speed of the frequency step change of the linear frequency modulation signal. if By performing an inverse Fourier transform at time t (t), we can obtain the one-dimensional range image of the focused scattering point:

[0072]

[0073] At this point, a one-dimensional impact signal in the distance dimension has been formed, and the azimuth dimension echo data will be subsequently accumulated and processed. The different processing of the azimuth dimension echo data can divide the imaging algorithm into two types: time domain and frequency domain, such as: back-projection imaging algorithm, frequency scaling imaging algorithm, range Doppler imaging algorithm, range migration imaging algorithm, etc. However, this patent mainly emphasizes a method of using proportional scaling to verify the indoor track model to simulate the actual battlefield high-speed mobile platform mounted with synthetic aperture radar to achieve guided flight. Therefore, its time / frequency domain imaging processing algorithm will not be described in detail.

[0074] Finally, the parameters for the simulated high-speed mobile platform required for the planning of the servo turntable system, synthetic aperture radar, and track system to complete an imaging guidance are issued, and the synthetic aperture radar transmits the recorded simulated sand table model echo data file to the internal processing unit, that is, the feasibility of the synthetic aperture radar mounted on the high-speed mobile platform can be verified through indoor simulation.

[0075] The following is further explained with reference to the accompanying drawings and experimental applications.

[0076] like Figure 1 As shown in the figure, the simulated high-speed mobile platform is mounted with a synthetic aperture radar and fixed at a certain position of the indoor track system. The mobile platform is as shown in the figure. Figure 2 As shown, the servo turntable system is mounted as Figure 3 As shown in the figure, a display and control interface is designed based on the designed indoor track system control module, servo turntable system control module, and synthetic aperture radar control module. This display and control interface is also used to plan the moving speed, moving distance, scanning mode, and related parameters required by the synthetic aperture radar in the horizontal / descent section of the simulated high-speed mobile platform.

[0077] Example 1

[0078] Example 1: The schematic diagram of the method of the present invention is used to simulate the horizontal segment guided flight of a high-speed mobile platform. Figure 4 shown.

[0079] To better illustrate Figure 4The synthetic aperture radar's location was set to 0m in range, 0m in azimuth, and 3.2m in altitude. A high-speed mobile platform's horizontal maneuvering flight trajectory was simulated, starting at 0m in azimuth and ending at 2.2m in azimuth. The synthetic aperture radar was mounted on the simulated high-speed mobile platform, which moved on the indoor track system according to the parameters issued by the indoor track system's display and control module.

[0080] Figure 5 The figure shows the application of the method of the present invention to the experimental process (horizontal section) of simulating the high-speed mobile platform radar start-up guidance flight, which includes the following steps:

[0081] A1) The simulated high-speed mobile platform is reset to zero. The simulated high-speed mobile platform is reset to the starting point of the indoor track system and waits for the platform movement and echo data collection instructions to be issued.

[0082] A2) Set the parameters of the simulated high-speed mobile platform on the indoor track system display and control interface, specifically: set the running distance of the simulated high-speed mobile platform for the first scanning segment, set the running distance of the simulated high-speed mobile platform for the second scanning segment, set the running speed of the simulated high-speed mobile platform for the first scanning segment, and set the running speed of the simulated high-speed mobile platform for the second scanning segment.

[0083] A3) Set the parameters of the servo turntable mounted on the simulated high-speed mobile platform on the servo turntable system display and control interface, specifically: set whether to perform a scanning action, set the scanning angle of the first scanning segment of the simulated high-speed mobile platform, and set the scanning angle of the second scanning segment of the simulated high-speed mobile platform.

[0084] A4) Set the parameters of the radar radio frequency of the servo turntable on the radar radio frequency system display and control interface, specifically: set the pulse width of the transmitted radar signal and set the signal bandwidth of the transmitted radar signal.

[0085] A5) After setting the parameters for the servo turntable system display and control interface, the radar RF system display and control interface, and the indoor track system display and control interface, align the timestamps of the simulated high-speed mobile platform and the radar RF module to zero. Specifically, set the time of the transmitted radar signal to zero and the time when the simulated high-speed mobile platform starts moving to zero.

[0086] A6) Simulate the high-speed mobile platform's movement and the radar RF module's data collection. Specifically, the high-speed mobile platform begins moving according to the parameters (distance and speed) issued by the display and control system, and the radar RF module samples the range dimension at each azimuth moment, mapped onto the sand table model on the slant range plane.

[0087] A61) The number of azimuth sampling points is calculated by dividing the movement distance issued by the indoor track system by the movement speed issued, to obtain the time consumed by the experiment. The time consumed by the experiment is then divided by the radar pulse repetition interval (pulse repetition interval = unit time / pulse repetition frequency) to obtain the number of azimuth sampling points.

[0088] A62) The radar radio frequency acquires range-azimuth two-dimensional echo data in real time. The data volume increases with the motion of the simulated high-speed mobile platform, and the final echo data volume is the number of azimuth sampling points multiplied by the number of range sampling points (number of range sampling points = unit time / range sampling frequency).

[0089] A7) Simulate the high-speed mobile platform stopping movement and the radar RF module stopping data collection. Specifically, simulate the high-speed mobile platform stopping movement (movement distance) according to the parameters issued by the display and control system, and the radar RF module stopping range sampling on the slant range plane mapped to the sand table model at the last azimuth moment.

[0090] A71) At this time, in order to facilitate the Fourier transform of the distance-azimuth two-dimensional echo data in the subsequent imaging processing process, by coinciding the position where the azimuth dimension is zero with the moment when the distance dimension data is collected is zero, and delaying the time at the end position, the data termination point can be located more conveniently during the echo data imaging processing, thereby simplifying the amount of data that needs to be calculated.

[0091] A8) After configuring the parameters for the servo turntable system display and control interface, the radar RF system display and control interface, and the indoor track system display and control interface, reset and align the timestamps of the simulated high-speed mobile platform and the radar RF module. Specifically, set the time reset for the transmitted radar signal and set the simulated high-speed mobile platform to be ready to receive the next stage of instructions from the indoor track system display and control unit.

[0092] A9) The radar beam illuminates the sand table scene and stores the diffusely reflected echoes. The data is sorted and distributed according to the azimuth and time dimensions. The data is converted into discrete echo data through A / D sampling within the radar RF system. At the same time, because the radar RF transmits a signal carried by the carrier frequency, digital down-conversion (de-carriering) is required at the hardware terminal to convert it to a baseband signal before echo imaging processing is performed.

[0093] A91) The original range-azimuth two-dimensional echo data contains the characteristic phase information of the target and scene clutter and noise. Generally, during the hardware processing process, it needs to be filtered through a high-pass filter and then the target characteristic phase information is recovered. In addition, the subsequent operation of echo signal processing, range-dimensional pulse compression, needs to be selected based on the characteristics of the signal itself.

[0094] A10) The range-azimuth two-dimensional echo data matrix imaging processing ultimately requires the formation of two impulse functions in both the range dimension and the azimuth dimension. A two-dimensional impulse sinc function can be obtained by orthogonally superimposing the two impulse functions.

[0095] A101) Before forming the two-dimensional impulsive sinc function, the range-dimensional pulse compression methods described above: the time-frequency domain matched filtering algorithm and the frequency-domain dechirp algorithm, can both convert the range-azimuth two-dimensional time-domain echo signal to time-domain focusing or frequency-domain focusing in the range dimension. However, due to the motion characteristics of the synthetic aperture radar, the distance variation between the radar and the target is subject to the Doppler effect. Therefore, after range compression, the image of the point target forms a curved curve in the image domain (azimuth dimension). This curve is actually an inverse curve function of the slant range history, and its variation prototype is shown in the following expression:

[0096]

[0097] A102) This curvature phenomenon is called range migration. Range migration is formed by the linear range movement and the quadratic range curvature in the phase history data, as shown in the following expression:

[0098]

[0099] A103) Different imaging algorithms use different correction methods, but the ultimate goal of the correction processing algorithm is to correct a curved straight line into a straight line and then perform azimuth compression. This patent of the present invention briefly describes the basic operations of the range Doppler algorithm in azimuth dimension processing. That is, the range Doppler algorithm deduces an azimuth frequency modulation function related to the radar speed based on the change relationship between the slant range history between the target and the radar. This function is the range migration correction function. Since the range Doppler algorithm is a frequency domain algorithm, it only needs to perform azimuth compression (azimuth dimension Fourier transform) after completing the range migration correction. If there is a large squint angle, there will be a secondary range migration correction. In this embodiment, the simulation is that the squint angle of the positive side view imaging is zero, so there is no large squint angle.

[0100] A11) Matching the echo imaging image with the prior optical image primarily simulates a high-speed mobile platform recording echo data and performing imaging processing in a horizontal section. Following the platform's actual operating mode, image matching and distance registration are performed with pre-stored internal optical prior information. By matching the imaging information image with the prior optical information image, the correctness of the guided flight path is confirmed and the need for guidance adjustment maneuvers is determined. This patent primarily emphasizes the use of an indoor track system to simulate the process and method of guided flight using a high-speed mobile platform equipped with a synthetic aperture radar. Therefore, image matching and distance registration will not be discussed in detail.

[0101] A12) Since this patented invention utilizes proportional scaling to simplify the process principle of radar-guided flight of a high-speed mobile platform in actual combat into a simulation method that uses an indoor track system to simulate a high-speed mobile platform, it also requires imaging processing of the data captured by the radar radio frequency and feeding it back to the display and control platform for related operations such as imaging result observation, imaging quality analysis, and image matching result display.

Claims

1. A method for simulating high-speed mobile platform guided flight by mounting a SAR radar on a track system, characterized in that: include: S0 builds a scene model sandbox and a guided flight simulation system, wherein the guided flight simulation system includes a track system, a servo turntable system, and a radar system, and is used to simulate the guided flight process of a high-speed mobile platform; S1 controls the servo turntable system to move the radar system along the track system according to the set moving distance and moving speed, while collecting the range-azimuth two-dimensional echo data of the scattering point targets on the scene model sand table; S2 performs imaging processing on the range-azimuth two-dimensional echo data to obtain an echo imaging image; S3 performs image matching and distance registration on the echo imaging image and the preset prior optical image.

2. The method according to claim 1, characterized in that The collecting of the range-azimuth two-dimensional echo data of the scattering point targets on the scene model sandbox includes: Calculate the azimuth dimension time quantity according to the moving distance and moving speed of the radar system and the radar pulse repetition interval of the radar system; Calculate the slant range from the scattering point target on the scene model sandbox to the radar system based on the operating altitude and moving speed of the radar system at the current azimuth moment; Traversing the azimuth dimension time, calculating the slant range history of all the scattering point targets to the radar system as phase history two-dimensional data; After performing pulse compression processing on the phase history two-dimensional data in the range dimension and data accumulation processing on the azimuth dimension, the range-azimuth two-dimensional echo data of the scattering point target are extracted from the obtained two-dimensional impulse function matrix.

3. The method according to claim 2, characterized in that The pulse compression processing of the two-dimensional phase history data in the distance dimension is achieved by de-linear frequency modulation.

4. The method according to claim 1, wherein The track system comprises a first track and a second track which are used to simulate the horizontal autonomous cruise maneuvering section and the downward dive flight maneuvering section in the missile flight trajectory respectively.

5. The method according to claim 4, characterized in that Before step S1, the method further includes the step of setting parameters of the servo turntable system, specifically including: Set whether to perform scanning action; Set the scanning angle of the radar system when operating in the first and second orbits respectively.

6. The method according to claim 1, characterized in that Before step S1, the method further includes setting parameters of the radar system, including setting the pulse width and signal bandwidth of the radar signal.

7. The method according to claim 1, characterized in that Before step S1 , the method further includes a step of aligning the time stamp of the radar transmission signal with the time when the radar system starts to move.

8. The method according to claim 1, characterized in that Before step S2, the method further includes the steps of sequentially performing high-pass filtering on the range-azimuth two-dimensional echo data and recovering target characteristic phase information.

9. The method according to claim 1, characterized in that The scene model sandbox is within the radar system beam range.

10. The method according to claim 1, characterized in that The guided flight simulation system is constructed by the following method: Obtaining the flight trajectory of the high-speed mobile platform to be simulated during the guided flight process; A track system is constructed to simulate the flight trajectory, and a radar system and a servo turntable system are mounted on the track system to respectively simulate the radar system and antenna servo mechanical system mounted on the high-speed mobile platform.

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