A Multi-Angle Track Spoofing and Interference FPGA Implementation Method Based on Pulse Group Measurement

Abstract

A multi-angle track deception jamming FPGA implementation method based on pulse group measurement includes the following steps: S1. Measuring the scanning period, main lobe width, and main lobe amplitude of the radar antenna; S2. Analyzing the yaw angle and track type according to the parameter configuration, releasing jamming at multiple angles to form multiple radial or oblique tracks; S3. Simulating the deception jamming motion characteristics. This invention can measure the radar main lobe position and scanning period in real time, and release jamming at the corresponding time based on the latest measured radar scanning period, thereby forming continuous tracks.

Description

Technical Field

[0001] This invention relates to the field of radar jamming technology, and more specifically, to an FPGA implementation method for multi-angle track deception jamming based on pulse group measurement. Background Technology

[0002] Track deception jamming typically employs sidelobe jamming. When the radar main lobe detects the jammer, the jammer remains silent and does not transmit jamming signals. When the radar sidelobe detects the jammer, it releases a decoy target, which modulates the received radar signal with time delay, Doppler, and amplitude modulation to simulate target motion characteristics. When the jamming power received by the radar sidelobe is greater than that received by the radar main lobe, the radar will interpret the current azimuth of its main lobe as the target's azimuth, thus achieving azimuth deception jamming.

[0003] Currently, many track jamming methods are based on the known radar rotation speed. After measuring the main lobe, jamming is released at the corresponding time according to the set track jamming azimuth, forming a continuous track. For variable-speed scanning radars, if jamming is released at the original time after the rotation speed is updated, it will result in discontinuous track azimuth. Summary of the Invention

[0004] To adapt to variable-speed antenna scanning, the present invention aims to provide an FPGA implementation method for multi-angle track deception jamming based on pulse group measurement. This method measures the radar main lobe position and scanning period in real time, and releases the jamming at the time corresponding to the latest measured radar scanning period, thereby forming a continuous track.

[0005] A method for implementing multi-angle track deception and interference using FPGA based on pulse group measurement includes the following steps:

[0006] S1. Measure the scanning period, main lobe width, and main lobe amplitude of the radar antenna;

[0007] S2. Based on the parameter configuration, analyze the yaw angle and track type, open windows at multiple angles to release interference, and form multiple radial or oblique tracks;

[0008] S3. Simulation of deceptive interference motion characteristics.

[0009] Further optimization, step S1 includes:

[0010] a) Initialize parameter configuration;

[0011] 1) Set a pulse measurement threshold, the value of which is between the main lobe and the side lobe;

[0012] 2) Set the maximum pulse interval time maxT. This maximum pulse interval time maxT is used to determine whether the pulse group has ended. The maximum pulse interval time maxT needs to be greater than the maximum pulse interval of the radar signal (pulse repetition period minus pulse width). If no pulse is detected after the maximum pulse interval time maxT is exceeded, the pulse group is considered to have ended.

[0013] 3) Set a pulse jitter threshold Ndither. The pulse jitter threshold Ndither is set to prevent individual points from exceeding or falling below the threshold due to noise, which could cause detection errors. In subsequent pulse detection, for rising edge detection, multiple consecutive points must be above the pulse jitter threshold Ndither for a pulse to be considered detected; for falling edge detection, multiple consecutive points must be below the pulse jitter threshold Ndither for a falling edge to be considered detected.

[0014] 4) Pulse detection flag Flag_Gpi: The pulse detection flag Flag_Gpi is used to mark whether the current pulse has exceeded the threshold. It is initially set to low (Flag_Gpi=0);

[0015] 5) Pulse group flag Flag_Pulse: The pulse group flag Flag_Pulse is used to mark whether the pulse group is currently active. It is initially set to low (Flag_Pulse=0);

[0016] 6) The number of pulses (Npulse) is used to count the number of pulses in a pulse group. It is initially set to 0.

[0017] b) GPI period, main lobe width, and amplitude detection;

[0018] 1) Perform envelope detection on the pulse amplitude to obtain the pulse envelope amplitude;

[0019] 2) Compare the pulse envelope amplitude with the threshold. If the pulse envelope amplitude is greater than the threshold, it is considered that a pulse has been detected, and the pulse flag is raised (Flag_Pulse=1). If the pulse envelope amplitude is less than the threshold, it is considered that the pulse has disappeared, and the pulse flag is lowered (Flag_Pulse=0).

[0020] 3) At the rising edge of the pulse marker, raise the pulse group flag (Flag_Gpi = 1);

[0021] 4) Starting from zero on the falling edge of the pulse marker, the counter counts in cycles. The counter increments by 1 for each cycle. When the pulse marker is detected to be high, the counter is reset to zero. If the counter duration is greater than the maximum pulse interval time maxT, the pulse group marker is pulled low (Flag_Gpi = 1), marking the end of pulse group width detection.

[0022] 5) When the pulse group is marked as high, count the number of pulses Npulse in the pulse group and the duration of the pulse group being marked as high gpi_temppw, then the pulse group width gpi_pw can be obtained (the duration of the pulse group being marked as high temppw minus the maximum pulse interval time maxT).

[0023] 6) When the pulse group is marked as high and the pulse mark is pulled high, count the pulse duration gpi_holdtime and accumulate the pulse amplitude to obtain the pulse energy and gpi_ampcsum; when the pulse group statistics are finished, the average amplitude of the pulse group is gpi_aveamp=gpi_ampcsum / gpi_holdtime;

[0024] 7) Repeat steps 1) to 6) to detect new pulse groups and count the rise times of the two pulse group flags Flag_Gpi to obtain the pulse group period gpi_pri;

[0025] c) Lock the test results;

[0026] 1) At the rising edge of the pulse group flag, assign the values ​​of the pulse count Npulse, pulse group width gpi_pw, pulse group average amplitude gpi_aveamp, and pulse group period gpi_pri of the previous pulse group to new variables.

[0027] 2) After initializing and configuring the number of pulses Npulse, pulse group width gpi_pw, gpi_aveamp, and pulse group period gpi_pri, perform the current pulse group detection;

[0028] 3) During a pulse group detection, the latching parameters remain unchanged until the next pulse group rising edge latches new data and then updates to the new parameters.

[0029] Further optimization, step S2 includes:

[0030] a) Analyze the yaw angle and track type configured by the user, and calculate the track occurrence time and track type;

[0031] 1) Based on the GPI measurement results, the pulse group measurement period gpi_pri corresponds to the radar antenna scanning time. The antenna rotates 360° in one scan. The time for the antenna to rotate 1° is calculated as gpi_pri / 360.

[0032] 2) Based on the configured yaw angle Ang (unit: °), with the radar main lobe ending time as t = 0, the track appearance start time is considered to be t = Ang * gpi_pri / 360; the track appearance time is set to the time corresponding to the main lobe width, i.e., gpi_pw;

[0033] 3) Analyze the track type. If it is a radial track, the track will not be deflected. The angle will appear at the same position each time, and the deflection time is dt = 0. If the track type is a slant track, the deflection angle corresponding to each scan of the antenna is calculated based on the angle slant speed PullAng (unit: ° / s): dAng = PullAng * gpi_pri. The corresponding deflection time is dt = dAng * gpi_pri / 360.

[0034] 4) If you want to form tracks at multiple angles, repeat steps 2) to 3) to calculate the starting times t1, t2, ..., tn corresponding to the tracks at multiple angles and the deflection times dt1, dt2, ..., dtn corresponding to the tracks;

[0035] b) Each time a new antenna scan cycle is detected, the time of occurrence of track interference is recalculated to adapt to the change in antenna rotation speed;

[0036] c) Based on the operating time, open windows at multiple angles to release interference, forming multiple radial or oblique tracks;

[0037] 1) The antenna scanning time is timed, with the end of the radar main lobe as t=0;

[0038] 2) If a radial track is formed, the simulated interference will be released when the time t is between [t1, t1+gpi_pw], [t2, t2+gpi_pw], ..., [tn, tn+gpi_pw]; (Note that t between [a, b] is equivalent to a≤t≤b);

[0039] 3) If a slanted track is formed, it is necessary to record which period of the scan has started since the track interference began, and record it as N. When the time t is in [t1+N*dt,t1+N*dt+gpi_pw], [t2+N*dt,t2+N*dt+gpi_pw], ..., [tn+N*dt,tn+N*dt+gpi_pw], the simulated interference will be released, thus forming a slanted track.

[0040] Further optimization, step S3 includes:

[0041] a) Analyze the trajectory deception interference configuration to simulate motion parameters, including the initial distance Rstart (m), the final distance Rstop (m), the initial velocity V0 (m / s, positive from far to near, negative from near to far), the acceleration a (m / s), and the cross-sectional area RCS (m²). 2 Once the parameters are resolved, the simulation is considered to have started, the target motion time is Tm = 0, and the interruption count is cnt = 0.

[0042] b) Simulate the motion characteristics of the target;

[0043] 1) The target motion is updated using an interrupt function with an interrupt period of Ts and a current interrupt count of cnt. Then the current simulation time is Tm = Ts * cnt.

[0044] 2) The current simulated distance is: Rt = Rstart - V0 * Tm - 0.5 * a * Tm * Tm;

[0045] 3) The current simulated velocity is: Vt = V0 + a * Tm;

[0046] 4) Calculate the current Doppler frequency fd = 2 * Vt / λ, where λ is the carrier wavelength, λ = c / fc, and c is the speed of light 3.0 × 10⁻⁶. 8 m / s, fc is the carrier frequency, in Hz;

[0047] 4) Determine whether the target motion has reached the endpoint. If it has reached the endpoint, the simulation ends. If Rstart ≥ Rstop, the target simulation ends when the current simulation distance Rt < Rstop. If Rstart < Rstop, the target simulation ends when the current simulation distance Rt > Rstop.

[0048] Compared with the prior art, the present invention has the following outstanding advantages:

[0049] This invention can measure the position and scanning period of the radar main lobe in real time, and release the interference at the time corresponding to the interference azimuth based on the latest measured radar scanning period, thereby forming a continuous flight track. Attached Figure Description

[0050] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention, but do not constitute a limitation thereof. In the drawings:

[0051] Figure 1 This is a schematic diagram of the radar scanning period (pulse group period) of the present invention;

[0052] Figure 2 This is a schematic diagram of the radar pulse reception method of the present invention;

[0053] Figure 3 This is a schematic diagram of pulse group measurement implemented by FPGA in this invention;

[0054] Figure 4 This is a schematic diagram of the trajectory deception windowing method of the present invention. Detailed Implementation

[0055] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0056] Example 1

[0057] This invention provides Embodiment 1, in combination with Figures 1-4 For example, for a mechanically scanned radar with a main lobe and sidelobe suppression ratio of 20dBc, the receiver channel is adjusted so that the amplitude of the radar main lobe illumination is 0dBm. A multi-angle track deception jamming FPGA implementation method based on pulse group measurement is provided for the radar of the above embodiment, including:

[0058] S1. Measure the radar antenna scanning period, main lobe width, and main lobe amplitude.

[0059] In step S1, the radar antenna scanning period, main lobe width, and amplitude are measured. The radar antenna scanning period, main lobe width, and amplitude are obtained by pulse group measurement of the input signal using an FPGA program.

[0060] according to Figure 1 It can be seen that gpi_pri (GPI detection pulse group repetition period) corresponds to the antenna scanning time period. gpi_pw (GPI detection pulse group width) corresponds to the radar main lobe duration. gpi_aveamp (GPI detection average power) corresponds to the radar main lobe average power.

[0061] Step S1 specifically includes:

[0062] a) Initialize parameter configuration;

[0063] 1) Set the pulse measurement threshold to -10dBm. The value of this pulse measurement threshold is between 0dBm in the main lobe and -20dBm in the side lobe.

[0064] 2) Set the maximum pulse interval time maxT. This maximum pulse interval time maxT is used to determine whether the pulse group has ended. maxT needs to be greater than the maximum pulse interval of the radar signal (pulse repetition period minus pulse width). If no pulse is detected after this interval, the pulse group is considered to have ended.

[0065] 3) Set the pulse jitter threshold Ndither = 10. This threshold is set to prevent individual points from exceeding or falling below the threshold due to noise, which could lead to detection errors. In subsequent pulse detection, for rising edge detection, 10 consecutive points above the threshold are required to indicate a pulse has been detected; for falling edge detection, 10 consecutive points below the threshold are required to indicate a falling edge has been detected.

[0066] 4) The pulse detection flag Flag_Gpi is used to mark whether the current pulse has exceeded the threshold. It is initially set to low (Flag_Gpi=0);

[0067] 5) The pulse group flag Flag_Pulse is used to mark whether the pulse group is currently active. It is initially set to low (Flag_Pulse=0);

[0068] 6) The number of pulses (Npulse) is used to count the number of pulses in a pulse group. It is initially set to 0.

[0069] b) See Figure 3 GPI period, main lobe width, and amplitude were detected.

[0070] 1) Perform envelope detection on the pulse amplitude to obtain the pulse envelope amplitude; envelope detection is an existing technology. In order to obtain the signal amplitude, since the signal is a complex signal, the real and imaginary parts are calculated to obtain the amplitude.

[0071] 2) Compare the pulse envelope amplitude with the threshold. If the pulse envelope amplitude is greater than the threshold, it is considered that a pulse has been detected, and the pulse flag is raised (Flag_Pulse=1). If the pulse envelope amplitude is less than the threshold, it is considered that the pulse has disappeared, and the pulse flag is lowered (Flag_Pulse=0).

[0072] 3) At the rising edge of the pulse marker, pull the pulse group flag high (Flag_Gpi=1).

[0073] 4) Starting from zero on the falling edge of the pulse marker, the counter increments by 1 for each beat. When the pulse marker goes high, the counter is reset to zero. If the counter duration is greater than maxT, the pulse group marker is pulled low (Flag_Gpi = 1), marking the end of a pulse group width detection.

[0074] 5) When the pulse group is marked as high, count the number of pulses Npulse in the pulse group and the duration of the pulse group being marked as high gpi_temppw, then the pulse group width gpi_pw (the duration of the pulse group being marked as high temppw minus maxT) can be obtained.

[0075] 6) When the pulse group is marked as high and the pulse mark is pulled high, count the pulse duration gpi_holdtime and accumulate the pulse amplitude to obtain the pulse energy and gpi_ampcsum. When the pulse group statistics are finished, the average amplitude of the pulse group is gpi_aveamp=gpi_ampcsum / gpi_holdtime.

[0076] 7) Repeat steps 1) to 6) to detect new pulse groups and count the rising edges of the two pulse group flags (Flag_Gpi) to obtain the pulse group period gpi_pri.

[0077] c) Lock the test results;

[0078] 1) At the rising edge of the pulse group flag, assign the pulse count Npulse, pulse width gpi_pw, pulse average amplitude gpi_aveamp, and pulse period gpi_pri of the previous pulse group to the new variables G_Npulse, G_gpi_pw, G_gpi_aveamp, and G_gpi_pri, respectively.

[0079] 2) After initializing and configuring the number of pulses Npulse, pulse group width gpi_pw, gpi_aveamp, and pulse group period gpi_pri, the current pulse group is detected.

[0080] 3) During a pulse group detection, the variables G_Npulse, G_gpi_pw, G_gpi_aveamp, and G_gpi_pri remain unchanged until the next pulse group rising edge latches new data and then updates the parameters.

[0081] S2. Based on the parameter configuration, analyze the yaw angle and track type, open windows at multiple angles to release interference, and form multiple radial or oblique tracks.

[0082] Step S2 includes:

[0083] a) Analyze the yaw angle and track type configured by the user, and calculate the track occurrence time and track type;

[0084] 1) Based on the GPI measurement results, the pulse group measurement period gpi_pri corresponds to the radar antenna scanning time. The antenna rotates 360° in one scan. The time for the antenna to rotate 1° is calculated as gpi_pri / 360.

[0085] 2) Based on the configured yaw angle Ang (unit: °), with the radar main lobe ending time as t = 0, the track appearance start time is considered to be t = Ang * gpi_pri / 360; the track appearance time is set to the time corresponding to the main lobe width, i.e., gpi_pw;

[0086] 3) Analyze the track type. If it is a radial track, no deflection processing is performed (track processing includes straight and diagonal tracks; for diagonal tracks, the signal window needs to move with each radar scan, and each movement angle is considered a deflection). Each time the angle appears at the same position, the deflection time is dt = 0. If the track type is a slanted track, the deflection angle corresponding to each antenna scan is calculated based on the slant speed PullAng (unit: ° / s): dAng = PullAng * gpi_pri, and the corresponding deflection time is...

[0087] dt = dAng * gpi_pri / 360;

[0088] 4) If multiple tracks are to be formed, repeat steps 2) to 3) to calculate the starting times t1, t2, ..., tn and the pull times dt1, dt2, ..., dtn corresponding to the multiple tracks;

[0089] b) Each time a new antenna scanning period is detected, the timing of track interference is recalculated according to step a) to adapt to the change in antenna rotation speed.

[0090] c) Based on the operational schedule, release interference by opening windows at multiple angles to create multiple radial or oblique tracks. (See also...) Figure 4 .

[0091] 1) The antenna scanning time is timed, with the end of the radar main lobe as t=0;

[0092] 2) If a radial track is formed, the simulated interference will be released when the time t is between [t1, t1+gpi_pw], [t2, t2+gpi_pw], ..., [tn, tn+gpi_pw]; (Note that t between [a, b] is equivalent to a≤t≤b);

[0093] 3) If a slanted track is formed, it is necessary to record which period of the scan has started since the track interference began, and record it as N. When the time t is in [t1+N*dt,t1+N*dt+gpi_pw], [t2+N*dt,t2+N*dt+gpi_pw], ..., [tn+N*dt,tn+N*dt+gpi_pw], the simulated interference will be released, thus forming a slanted track.

[0094] S3. Deceptive interference motion characteristic simulation;

[0095] Step S3 includes:

[0096] a) Analyze the trajectory deception interference configuration to simulate motion parameters, including the initial distance Rstart (m), the final distance Rstop (m), the initial velocity V0 (m / s, positive from far to near, negative from near to far), the acceleration a (m / s), and the cross-sectional area RCS (m²). 2 Once the parameters are resolved, the simulation is considered to have started, the target motion time is Tm = 0, and the interruption count is cnt = 0.

[0097] b) Simulate the motion characteristics of the target;

[0098] 1) The target motion is updated using an interrupt function with an interrupt period of Ts and a current interrupt count of cnt. Then the current simulation time is Tm = Ts * cnt.

[0099] 2) The current simulated distance is: Rt = Rstart - V0 * Tm - 0.5 * a * Tm * Tm;

[0100] 3) The current simulated velocity is: Vt = V0 + a * Tm;

[0101] 4) Calculate the current Doppler frequency fd = 2 * Vt / λ, where λ is the carrier wavelength, λ = c / fc, and c is the speed of light (3.0 × 10⁻⁶). 8 (m / s), where fc is the carrier frequency in Hz;

[0102] 4) Determine if the target has reached its endpoint. If it has, the simulation ends. If Rstart ≥ Rstop, the simulation ends when the current simulation distance Rt < Rstop. If Rstart < Rstop, the simulation ends when the current simulation distance Rt > Rstop.

[0103] Example 2

[0104] Since the average power of the radar main lobe is calculated during GPI detection, this power can be used as a reference for the system's adaptive detection threshold, avoiding poor performance caused by unreasonable manual threshold settings by the user. For example, using this threshold as a reference, reducing it by X1dB (determined based on the radiation pattern characteristics of the adapted system) serves as the sidelobe concealment threshold; using this threshold as a reference, reducing it by X2dB (determined based on the radiation pattern characteristics of the adapted system) serves as the signal reconnaissance envelope detection threshold.

[0105] Based on Embodiments 1 and 2, the present invention can measure the position and scanning period of the radar main lobe in real time, and release the interference at the time corresponding to the interference azimuth based on the latest measured radar scanning period, thereby forming a continuous flight track.

Claims

1. A method for implementing multi-angle track deception and interference using FPGA based on pulse group measurement, characterized in that, Includes the following steps: S1. Measure the scanning period, main lobe width, and main lobe amplitude of the radar antenna; Step S1 includes: a) Initialize parameter configuration; 1) Set a pulse measurement threshold, the value of which is between the main lobe and the side lobe; 2) Set the maximum pulse interval time maxT. This maximum pulse interval time maxT is used to determine whether the pulse group has ended. The maximum pulse interval time maxT needs to be greater than the maximum pulse interval of the radar signal. If no pulse is detected after the maximum pulse interval time maxT is exceeded, the pulse group is considered to have ended. 3) Set a pulse jitter threshold Ndither. The pulse jitter threshold Ndither is set to prevent individual points from exceeding or falling below the threshold due to noise, which could cause detection errors. In subsequent pulse detection, for rising edge detection, multiple consecutive points must be above the pulse jitter threshold Ndither for a pulse to be considered detected; for falling edge detection, multiple consecutive points must be below the pulse jitter threshold Ndither for a falling edge to be considered detected. 4) Pulse detection flag Flag_Gpi: The pulse detection flag Flag_Gpi is used to mark whether the current pulse has exceeded the threshold. It is initially set to low. 5) Pulse group flag_Pulse: The pulse group flag_Pulse is used to mark whether the pulse group is currently active. It is initially set to low. 6) The number of pulses (Npulse) is used to count the number of pulses in a pulse group. It is initially set to 0. b) GPI period, main lobe width, and amplitude detection; 1) Perform envelope detection on the pulse amplitude to obtain the pulse envelope amplitude; 2) Compare the pulse envelope amplitude with the threshold. If the pulse envelope amplitude is greater than the threshold, it is considered that a pulse has been detected and the pulse marker is raised. If the pulse envelope amplitude is less than the threshold, it is considered that the pulse has disappeared and the pulse marker is lowered. 3) At the rising edge of the pulse marker, raise the pulse group marker; 4) Starting from zero at the falling edge of the pulse marker, the counter counts in cycles. The counter increments by 1 for each cycle. When the pulse marker is detected to be high, the counter is reset to zero. If the counter duration is greater than the maximum pulse interval time maxT, the pulse group marker is pulled low, marking the end of pulse group width detection. 5) When the pulse group is marked as high, count the number of pulses Npulse in the pulse group and the duration of the pulse group being marked as high gpi_temppw, then the pulse group width gpi_pw can be obtained; 6) When the pulse group is marked as high and the pulse mark is pulled high, count the pulse duration gpi_holdtime and accumulate the pulse amplitude to obtain the pulse energy and gpi_ampcsum; when the pulse group statistics are finished, the average amplitude of the pulse group is gpi_aveamp=gpi_ampcsum / gpi_holdtime. 7) Repeat steps 1) to 6), detect new pulse groups, and count the rise times of the two pulse group flags Flag_Gpi to obtain the pulse group period gpi_pri; c) Lock the test results; 1) At the rising edge of the pulse group flag, assign the values ​​of the pulse count Npulse, pulse group width gpi_pw, pulse group average amplitude gpi_aveamp, and pulse group period gpi_pri of the previous pulse group to new variables. 2) After initializing and configuring the number of pulses Npulse, pulse group width gpi_pw, gpi_aveamp, and pulse group period gpi_pri, perform the current pulse group detection; 3) During the detection of a pulse group, the latching parameters remain unchanged until the rising edge of the next pulse group latches new data and then updates to the new parameters; S2. Based on the parameter configuration, analyze the yaw angle and track type, open windows at multiple angles to release interference, and form multiple radial or oblique tracks; Step S2 includes: a) Analyze the yaw angle and track type configured by the user, and calculate the track occurrence time and track type; 1) Based on the GPI measurement results, the pulse group measurement period gpi_pri corresponds to the radar antenna scanning time. The antenna rotates 360° in one scan. The time for the antenna to rotate 1° is calculated as gpi_pri / 360. 2) Based on the configured yaw angle Ang, with the radar main lobe ending time as t=0, the track appearance start time t=Ang*gpi_pri / 360 is considered; the track appearance time is set to the time corresponding to the main lobe width, i.e. gpi_pw; 3) Analyze the track type. If it is a radial track, the track will not be deflected. The angle will appear at the same position each time, and the deflection time is dt=0. If the track type is a slant track, the deflection angle corresponding to each scan of the antenna is calculated according to the angle slant speed PullAng: dAng=PullAng*gpi_pri. The corresponding deflection time is dt=dAng*gpi_pri / 360. 4) If you want to form tracks at multiple angles, repeat steps 2) to 3) to calculate the starting times t1, t2, ..., tn corresponding to the tracks at multiple angles and the deflection times dt1, dt2, ..., dtn corresponding to the tracks; b) Each time a new antenna scan cycle is detected, the time of occurrence of track interference is recalculated to adapt to the change in antenna rotation speed; c) Based on the operational schedule, open windows at multiple angles to release interference, forming multiple radial or oblique tracks; 1) The antenna scanning time is timed, with the end of the radar main lobe as t=0; 2) If a radial track is formed, the simulated interference will be released when the waiting time t is in [t1, t1+gpi_pw], [t2, t2+gpi_pw], ..., [tn, tn+gpi_pw]. 3) If a slanted track is formed, it is necessary to record which period of the scan has started since the track interference began, and record it as N. When the time t is in [t1+N*dt, t1+N*dt+gpi_pw], [t2+N*dt, t2+N*dt+gpi_pw], ..., [tn+N*dt, tn+N*dt+gpi_pw], the simulated interference will be released, thus forming a slanted track. S3. Simulation of deceptive interference motion characteristics.

2. The FPGA implementation method for multi-angle track spoofing interference based on pulse group measurement according to claim 1, characterized in that, Step S3 includes: a) Analyze the trajectory deception and interference configuration to simulate motion parameters, including the starting distance Rstart, the ending distance Rstop, the initial velocity V0, the acceleration a, and the cross-sectional area RCS; once the parameters are analyzed, the simulation is considered to have started, the target motion time is Tm=0, and the interruption count cnt=0. b) Simulate the motion characteristics of the target; 1) The target motion is updated using an interrupt function with an interrupt period of Ts and a current interrupt count of cnt. Then the current simulation time is Tm = Ts * cnt. 2) The current simulated distance is: Rt = Rstart - V0 * Tm - 0.5 * a * Tm * Tm; 3) The current simulated velocity is: Vt = V0 + a * Tm; 4) Calculate the current Doppler frequency fd = 2 * Vt / λ, where λ is the carrier wavelength, λ = c / fc, and c is the speed of light 3.0 × 10⁻⁶. 8 m / s, fc is the carrier frequency, in Hz; 4) Determine whether the target motion has reached the endpoint. If it has reached the endpoint, the simulation ends. If Rstart ≥ Rstop, the target simulation ends when the current simulation distance Rt < Rstop. If Rstart < Rstop, the target simulation ends when the current simulation distance Rt > Rstop.

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