A method for directing an unmanned aerial vehicle to a path based on location deception

Abstract

The application discloses a kind of based on position deception UAV directional induction path planning method, obtain the real position of unmanned aerial vehicle using radar, comprehensively consider unmanned aerial vehicle preset trajectory, real position and target area center point position, to reach the center point of target area as the purpose of fastest construction reasonable deception point position, finally according to the position of deception point obtains forwarding delay scheme, and makes forwarding delay and minimum, while the application gives the quantitative determination method of reasonable deception point position, and when the position of deception point is unreasonable, back adjustment scheme, when forwarding deception is carried out to unmanned aerial vehicle, there is clear index, avoid unnecessary redundant consideration, as far as possible fast deception unmanned aerial vehicle to target area.

Description

Technical Field

[0001] This invention belongs to the field of drone guidance technology, specifically a drone guidance path planning method based on location deception. Background Technology

[0002] With the rapid development of drone technology, its application in the military field is becoming increasingly widespread, making the issue of how to counter the threat of enemy drones a pressing research topic. Limited by the pre-positioned locations of weapons and equipment, the enemy can use intelligence information to plan the attack paths of drones, thereby reducing the probability of drones being shot down and significantly increasing the cost of physical downing for our side. Using electromagnetic interference to cut off the enemy's control over drones can cause them to fail in their missions and return to base or engage in unpredictable behavior, making it impossible to effectively strike the enemy and posing unpredictable dangers to our own positions. Therefore, whether from the perspective of improving strike efficiency, protecting our own positions, or eliminating the enemy, luring enemy drones to a designated area undetected and then capturing or striking them is a superior solution.

[0003] Chinese patent application CN111624627A discloses a method and system for drone guidance based on position deception. The system describes the functional modules for implementing position deception, mainly including an array antenna unit, a signal receiving unit, a target tracking unit, a strategy generation unit, and a guidance signal generation unit. The system describes the steps of drone guidance based on position deception, but it only provides a method for generating pseudorange delay based on the ephemeris information of all visible satellites, the current position of the target drone, and the expected position of the target drone at the next moment; it does not provide a method for determining the expected position of the drone at the next moment. Chinese patent application CN118050751B discloses a method and system for drone guidance based on position deception. This method provides a method for determining the expected position of the drone at the next moment and proposes a flight fluctuation coefficient index to avoid unreasonable position deception causing the drone to detect the deception. However, this method aims to enable the drone to reach its preset true destination normally and is not suitable for military applications.

[0004] A Chinese patent application with publication number CN111650620B discloses a method for determining the flight speed and direction of a drone using the parallelogram law. This only qualitatively reduces the likelihood of detection of deception. While it lowers the probability of detection, it significantly increases the time required to fly towards the target area. The patent employs various methods to reduce the deviation between the deception trajectory and the preset trajectory, but this method is based on qualitative analysis and lacks reasonable indicators for quantitative analysis to determine the validity of the deception point's location at a given moment. This patent attempts to meet the requirements of deception stealth by using significant redundancy, greatly sacrificing deception efficiency.

[0005] Therefore, for a designated area, how to plan the expected position of the drone at each moment, so as to ensure that the deception behavior is not detected by the drone, and to lure the drone to the designated area in a short time, is an important problem that needs to be solved urgently when applying the location deception drone inducement method to military scenarios. Summary of the Invention

[0006] Based on the above analysis, the present invention aims to provide a UAV orientation guidance path planning method based on location deception, in order to solve the problem that existing methods cannot achieve fast, efficient and covert target UAV navigation deception.

[0007] To achieve the above-mentioned objectives, the present invention includes the following steps:

[0008] Step (1): After our radar can stably track the enemy drone, we decide to start the deception at T0. At this time, the drone's planned position is PL(0) and its real position is RL(0). Therefore, RL(0) = PL(0).

[0009] Step (2), Preliminary determination of flight direction: For any T k At time k = 0, 1, 2, ..., the line connecting the actual location of the UAV and the center point of the target area is taken as the expected flight direction of the UAV, and its direction vector is expressed as: Where D represents the expected final target location for the drone;

[0010] Step (3): Determine the deception displacement based on the drone's speed: Assume the drone's speed is T. k To T k+1 The displacement vector is: Where V max This is the maximum flight speed of the drone;

[0011] Step (4): Based on the displacement vector Given the position PL(k+1) at time k+1 on the drone's preset path, the position ML(k) of the deception point is obtained:

[0012]

[0013] That is, T k At that moment, the drone believed it was at ML(k), and the drone followed the displacement vector determined in step (3). Advance, to achieve the purpose of deception;

[0014] Step (5): Determine whether the location of the deception point obtained in step (4) is reasonable. If the location of the deception point is considered reasonable, and the delay information is obtained, jump to (7). If the location of the deception point is considered unreasonable, then execute step (6) to replan.

[0015] Step (6): When the location of the deception point is determined to be unreasonable, a rollback is performed. After the rollback is completed, the process jumps to step (5).

[0016] Step (7): Generate a deception signal based on the time delay information obtained in step (5) and send it to the UAV;

[0017] Step (8): Determine whether the real position RL(k+1) is within the target area. If it is within the target area, issue a signal to shoot down or capture the drone. If it is not within the target area, jump to step (2) until the preset trajectory processing is completed.

[0018] Furthermore, step (5) involves determining whether the location of the deception point is reasonable, specifically including:

[0019] Construct the following linear programming problem: Based on the pseudo-range equations of the true location and the pseudo-range equations of the deception point, obtain the time delay equations. Combine the clock error constraint to construct the constraint equations. Under the constraints of the constraint equations, solve for the minimum value of the time delay sum of the time delay equations. If a solution exists, the location of the deception point is considered reasonable; if no solution exists, the location of the deception point is considered unreasonable.

[0020] Furthermore, the rollback process in step (6) specifically includes:

[0021] The location of the deception point at time k is obtained:

[0022] ML(k) = RL(k-1)

[0023] Correct the drone's flight direction and velocity, where the drone's flight direction vector at time k is:

[0024]

[0025] Drone flight speed:

[0026]

[0027] Where V min The true displacement vector of the UAV at its minimum flight speed Update the real position in the next moment.

[0028] Furthermore, V max The value is taken as 0.15 km / s; V min The value is 0.1 km / s.

[0029] This invention is based on a position deception method. Based on the UAV's current true position and a preset trajectory, it calculates the ideal deception point from the angle of fastest arrival at the target position. According to clock difference constraints, time delay, and the minimum target, it judges whether the ideal deception point's position is reasonable. If the ideal deception is unreasonable, it means the UAV's true position deviates too far from the preset trajectory and needs adjustment. In this case, the UAV's deception point position is reverted, causing the UAV's next movement direction to align with the preset trajectory, thus making the true trajectory more reasonable. In this way, the reasonableness of the UAV's deception point position is judged quantitatively, rather than qualitatively, ultimately enabling the UAV to deviate from the preset trajectory to the maximum extent while meeting the deception stealth requirements. Attached Figure Description

[0030] Figure 1 It is a planar diagram of the unmanned preset trajectory and the actual trajectory;

[0031] Figure 2 This is a detailed image of the actual trajectory of the drone. Detailed Implementation

[0032] The specific embodiments of the present invention will now be described with reference to the accompanying drawings to enable those skilled in the art to better understand the invention. It should be particularly noted that in the following description, detailed descriptions of known functions and designs that might obscure the main content of the invention will be omitted here.

[0033] 1. The principle of location spoofing interference in forwarding spoofing

[0034] In military scenarios, signal decryption is difficult, so repeater-based deception jamming methods are often used. After receiving the satellite signal, the jammer adds time delay information, amplifies the power, and retransmits it, overwriting the original satellite signal to achieve deception and jamming of the target.

[0035] Assume that the UAV, during flight, constructs a pseudorange equation system by receiving signals from four satellites to achieve three-dimensional coordinate positioning. Assume the coordinates of the four navigation satellites are S1, S2, S3, and S4, and the UAV's true coordinates are P.

[0036] For the true position P, its pseudorange equations can be expressed as:

[0037]

[0038] in, These are the pseudorange measurement of the actual position of the UAV from the i-th satellite and the distance between the satellite and the actual position of the UAV, respectively, where c is the speed of light and Δt is the distance between the satellite and the UAV. P This refers to the clock difference between the user's clock and the satellite clock.

[0039] Assuming the deception coordinates of the drone are M, the pseudorange equations for the location M of the deception point can be expressed as:

[0040]

[0041] in, Let Δt be the pseudorange measurement of the position of the i-th satellite relative to the deception point, and Δt be the actual distance between the satellite and the deception point of the UAV. M The clock difference between the user clock and the satellite clock includes a fixed delay caused by the jammer's position relative to the deception point.

[0042] Assume the forwarding delays are τ. i (i = 1, 2, 3, 4), according to equations (1) and (2):

[0043]

[0044] Where, Δt=Δt P -Δt M This is a clock bias jump.

[0045] According to the given conditions, the following constraints apply:

[0046]

[0047] To minimize the total forwarding latency, it can be expressed as:

[0048] Under the constraints of equations (3) and (4), find τ i (i = 1, 2, 3, 4) such that Minimum.

[0049] This is a typical linear programming problem; the solution is τ. i Then, the jammer can be controlled according to the delay scheme to generate the desired deception signal and deceive the drone.

[0050] Under normal circumstances, once our position is set up, the location of the jammer will not change, and the jamming range of the jammer is limited. If the enemy drone wants to attack our position, it will inevitably fall into the working range of our jammer. There is no need to consider the situation where our jammer cannot jam the enemy drone. If the enemy drone is outside the working range of our jammer, it can be considered as not threatening our position and can be left unattended.

[0051] The calculated clock difference between the drone's true location and the location of the deception point is affected by the distance from the jammer to the drone's deception point. This is a crucial indicator for detecting whether the drone has been deceived, and an alarm will be triggered when it exceeds a preset threshold. We don't need to be overly concerned with the distance between the deception point and the jammer; we only need to ensure that the calculated clock difference satisfies the constraints after the location of the deception point is determined. Furthermore, if the forwarding delay is minimized, the probability of detecting the deception is minimized.

[0052] 2. Trajectory deception interference principle in forwarding deception

[0053] Considering that the UAV performs automatic navigation after entering the interference airspace, it completes its flight mission by flying along a preset trajectory using its own proportional-differential controller. When the waypoints on each predetermined trajectory are infinitely close, it can be assumed that the UAV is moving at a constant speed in a straight line between adjacent waypoints, and the speed is the quotient of the distance between the two waypoints and the time difference between them. At each waypoint, by default, the UAV will have already deflected its flight direction based on its current calculated position and the preset trajectory waypoints.

[0054] Knowing the drone's trajectory, the drone's flight direction and speed can be controlled by adjusting the relative positions of the deception point and the preset waypoint. By controlling the position of the drone's deception point point by point, the drone's real flight trajectory can be controlled relatively accurately, thereby luring it to a safe area.

[0055] Considering the UAV's flight speed range is [0.1, 0.15], and the trajectory sampling interval is 1 second.

[0056] To lure the drone to the target area as quickly as possible, after each deception signal is sent, the expectation is that the drone will move towards the target point at top speed. Therefore, the direction of movement should be... The speed should be consistent with that of the UAV at time k, where RL(k) is the actual position of the UAV at time k, and D is the expected target position that the UAV will eventually reach.

[0057] Assume the drone always flies at a speed of 0.15 km / s, and adjusts its flight direction promptly each time it receives location information. Ignore the influence of the external environment on the drone, and assume it moves at a constant velocity in a straight line along its initial direction.

[0058] This invention provides a method for unmanned aerial vehicle (UAV) orientation guidance path planning based on location spoofing, comprising the following steps:

[0059] (1) After our radar can stably track the enemy drone (hereinafter referred to as drone), the moment to start the deception is T0. Since no deception has been carried out before, the drone is still on the planned flight path. At this time, the planned position of the drone is PL(0), the actual position is RL(0), and RL(0) = PL(0).

[0060] (2) Preliminary determination of flight direction. For any T k Time, k = 0, 1, 2, ..., where k represents time, k = 0 indicates the start of the deception, and subsequent integers represent the times when the deception device sends the deception signal. The line connecting the actual location of the drone and the center point of the target area is taken as the expected flight direction of the drone, and its direction vector can be expressed as... D represents the target location that the drone is expected to eventually reach.

[0061] (3) Determine the deception displacement based on the drone's speed. Assume the drone's speed is T. k To T k+1 The displacement vector is: 0.15 represents the maximum flight speed of the drone, measured in km / s.

[0062] (4) Based on the displacement vector and the position of the UAV at time k+1 on the preset path, the position ML(k) of the deception point can be obtained:

[0063]

[0064] That is, T k At any given moment, the drone, believing it is in ML(k), will displace according to (3). Advance, to achieve the goal of deception.

[0065] (5) Determine whether the location of the deception point is reasonable.

[0066] It is generally believed that a small clock bias jump is within the tolerance range of a drone, making deception difficult to detect. Therefore, constraining the clock bias jump amplitude can effectively prevent deception from being detected. At the same time, if the total delay is the shortest under this constraint, it is the least likely to be detected.

[0067] Construct the following linear programming problem: Based on the pseudo-range equations of the true location and the pseudo-range equations of the deception point, obtain the time delay equations. Combine the clock error constraint to construct the constraint equations, and solve for the minimum value of the time delay sum under these constraints.

[0068] If a solution exists, the location of the deception point is considered reasonable, and the time delay information is obtained and the jump is to (7);

[0069] If no solution exists, the location of the deception point is considered unreasonable and needs to be replanned (6).

[0070] (6) The location of the deception point is unreasonable. A rollback is performed, and after the rollback is completed, the user is redirected to (5). The rollback process is as follows:

[0071] Since the drone's true position at time k-1 can be mapped to the position of the deception point, it indicates that the drone's true position is within a reasonable range. Therefore, the position of the deception point at time k can be directly obtained:

[0072] ML(k) = RL(k-1).

[0073] Correcting the drone's flight direction and speed,

[0074] At time k, the UAV's flight direction vector is:

[0075]

[0076] Drone flight speed:

[0077]

[0078] True displacement vector Update the actual location in the next moment:

[0079] (7) Generate a deception signal based on the time delay information obtained in (5) and send it to the UAV.

[0080] (8) Determine whether RL(k+1) is within the target area. If it is, send a signal. If it is not, jump to (2) until the preset trajectory processing is completed. Even if the UAV is already within the safe area, it is still necessary to continue sending deception signals according to the above algorithm to prevent the UAV from escaping after obtaining the real position.

[0081] 3. Simulation Results

[0082] To facilitate explanation, understanding, and simplify computation, the simulation background is primarily a two-dimensional plane. Three-dimensional simulation can be extended and expanded according to the algorithm's logic; however, it will not be demonstrated here. In the simulation, the jammer's coordinates are (0, 0, 0.3) km and remain fixed; the UAV's initial position is (30, 1.302, 0.3) km. The visible satellite coordinates of the enemy UAV and the jammer are: S1(-1863, 19278, -5944) km, S2(-1915, 18807, 7284) km, S3(-2075, 19597, 4743) km, and S4(-1927, 18959, 6876) km, respectively.

[0083] In the simulation example, the enemy drone's speed varies within the range of [0.1, 0.15] km / s. Because the time interval between adjacent deception moments is short, it can be assumed that the drone moves at a constant speed in a straight line during this period, and that the drone's speed change can be completed instantaneously. The drone's preset trajectory is known, and the target area is:

[0084]

[0085] Each satellite signal delay and clock jump should satisfy the constraint of equation (4).

[0086] The deception begins at time 0, and three segments of the drone's preset and actual trajectories at different times are captured, as shown in Tables 1, 2, and 3:

[0087] Table 1. Preset trajectory coordinates, actual trajectory coordinates, and delay scheme at times 0-8

[0088] time 0 1 2 3 4 5 6 7 8 PL-X 30 29.9 29.8 29.7 29.6 29.5 29.4 29.3 29.2 PL-Y 1.302 1.302 1.302 1.302 1.302 1.302 1.302 1.302 1.302 PL-Z 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 RL-X 30 29.86056 29.72113 29.58169 29.44225 29.30281 29.16338 29.02394 28.8845 RL-Y 1.302 1.357293 1.412585 1.467878 1.523171 1.578464 1.633756 1.689049 1.744342 RL-Z 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 <![CDATA[τ1]]> 3.95E-09 7.89E-09 1.18E-08 1.58E-08 1.97E-08 2.37E-08 2.76E-08 3.16E-08 3.55E-08 <![CDATA[τ2]]> 2.56E-12 8.64E-13 6.37E-14 3.11E-17 7.7E-15 3.51E-16 3.19E-11 3.21E-11 3.24E-11 <![CDATA[τ3]]> 8.13E-09 1.63E-08 2.44E-08 3.25E-08 4.06E-08 4.88E-08 5.69E-08 6.5E-08 7.32E-08 <![CDATA[τ4]]> 1.47E-09 2.92E-09 4.39E-09 5.85E-09 7.31E-09 8.77E-09 1.03E-08 1.17E-08 1.32E-08

[0089] Table 2. Preset trajectory coordinates, actual trajectory coordinates, and delay scheme for times 115-123.

[0090] time 115 116 117 118 119 120 121 122 123 PL-X 17.16092 17.02794 16.89496 16.76198 16.62901 16.49603 16.36305 16.23008 16.0971 PL-Y 1.302 1.302 1.302 1.302 1.302 1.302 1.302 1.302 1.302 PL-Z 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 RL-X 13.96473 13.82529 13.68586 13.54642 13.40698 13.26754 13.12811 12.98867 12.84923 RL-Y 7.660664 7.715957 7.77125 7.826542 7.881835 7.937128 7.99242 8.047713 8.103006 RL-Z 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 <![CDATA[τ1]]> 4.69E-07 4.74E-07 4.78E-07 4.82E-07 4.86E-07 4.9E-07 4.95E-07 4.99E-07 5.03E-07 <![CDATA[τ2]]> 2.31E-13 2E-13 1.71E-13 1.46E-13 1.23E-13 1.02E-13 8.38E-14 6.79E-14 5.62E-14 <![CDATA[τ3]]> 9.07E-07 9.14E-07 9.22E-07 9.29E-07 9.36E-07 9.43E-07 9.51E-07 9.58E-07 9.65E-07 <![CDATA[τ4]]> 1.67E-07 1.68E-07 1.7E-07 1.71E-07 1.72E-07 1.74E-07 1.75E-07 1.77E-07 1.78E-07

[0091] Table 3. Preset trajectory coordinates, actual trajectory coordinates, and delay scheme at times 237-245.

[0092] time 237 238 239 240 241 242 243 244 245 PL-X 1.095576 0.971195 0.847119 0.723276 0.599555 0.475809 0.351862 0.227522 0.102606 PL-Y 1.306907 1.309493 1.312698 1.31661 1.321302 1.326817 1.333152 1.340247 1.347976 PL-Z 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 RL-X 0.547138 0.528299 0.532274 0.51936 0.506446 0.505875 0.501953 0.498302 0.499436 RL-Y 12.62766 12.77647 12.62652 12.77597 12.92541 12.77541 12.92536 12.7754 12.9254 RL-Z 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 <![CDATA[τ1]]> 8.85E-07 1.14E-08 8.86E-07 8.98E-07 1.15E-08 8.99E-07 1.16E-08 9E-07 9.13E-07 <![CDATA[τ2]]> 2.88E-16 3.02E-13 2.51E-16 4.3E-15 2.99E-13 2.91E-16 2.98E-13 2.47E-16 4.07E-15 <![CDATA[τ3]]> 1.48E-06 1.96E-08 1.48E-06 1.49E-06 1.95E-08 1.48E-06 1.94E-08 1.48E-06 1.49E-06 <![CDATA[τ4]]> 2.88E-07 3.77E-09 2.87E-07 2.91E-07 3.77E-09 2.9E-07 3.76E-09 2.89E-07 2.92E-07

[0093] Wherein, PL-X, PL-Y, and PL-Z represent the X, Y, and Z coordinates of the preset trajectory, respectively; similarly, RL-X, RL-Y, and RL-Z represent the X, Y, and Z coordinates of the actual trajectory, respectively; and τ1, τ2, τ3, and τ4 represent the forwarding delays of the signals corresponding to satellites S1, S2, S3, and S4, respectively.

[0094] At time 237, the drone approached the target area very closely, and at time 238, it officially entered the target area. Within the target area, the same interference strategy continued, causing the drone to move as close as possible to the center of the target area, buying time to capture or shoot it down. As long as the preset trajectory information is available, this plan can continue indefinitely, preventing the drone from escaping.

[0095] More intuitively, Figure 1The drone's trajectory is described. The red and yellow solid lines represent the drone's true trajectory and preset trajectory, respectively; the blue dashed line connects the deception points at different times; and the area formed by the orange dashed line is the safe zone. Starting at time 0, the drone moves in the direction that fastest reaches the center of the target area. Initially, the difference between the true trajectory and the preset trajectory is small, making the deception difficult to detect. At this point, the drone can proceed towards the target area at top speed until time 196. Because the difference between the true trajectory and the preset trajectory becomes too large, there is no reasonable delay scheme to prevent the deception from being detected. Therefore, a backtracking process is adopted, and the deception point is selected as the position at time 195 of the true trajectory. The drone moves towards the position at time 197 of the preset trajectory to reduce the difference between the true and preset trajectories. It can be seen that the drone's true trajectory can no longer maintain a straight line but deviates towards the preset trajectory. At time 197, after the trajectory adjustment at time 196, the drone finds a reasonable delay scheme and continues to move towards the target area in the fastest direction. Afterward, the position of the drone's deception point begins to jump back and forth between the true trajectory and the preset trajectory to continuously adjust the drone's position to maintain the stealth of the deception. This process repeats itself, and the final trajectory is a curve.

[0096] Although the deception trajectory fluctuates significantly as the drone approaches the target area due to the large distance between its actual and preset positions, it is certain that despite these fluctuations, the location of the deception point remains within a reasonable range based on the delay calculation results, and therefore will not be detected by the drone. This process ensures the drone flies under extreme conditions, minimizing the time required to reach the target area. After approaching the center point of the target area, the drone repeatedly wobbles around it, unable to shake off the deception.

[0097] Further from Figure 2 It can be seen that, under normal circumstances, the drone can correct its deviation from the preset trajectory with just one adjustment, indicating that the backtracking correction method is quite effective. However, when the drone deviates significantly from the preset trajectory, frequent corrections are necessary to ensure that the deceptive behavior is not detected by the drone.

[0098] Although the illustrative specific embodiments of the present invention have been described above to enable those skilled in the art to understand the invention, it should be understood that the invention is not limited to the scope of the specific embodiments. For those skilled in the art, various changes are obvious as long as they are within the spirit and scope of the invention as defined and determined by the appended claims, and all inventions utilizing the concept of the present invention are protected.

Claims

1.A method for drone directed induction path planning based on location spoofing, the method comprising: Comprising the following steps: Step (1), after our radar can stable track enemy UAV, with the time of deciding to start deception as , at this time the UAV plan position is , the real position , has ; Step (2), preliminary determination of the flight direction: for any moment, the line connecting the real position of the UAV and the center point position of the target region is taken as the flight direction of the UAV, and the direction vector is represented as wherein is the target position where the UAV is expected to finally arrive. Step (3), determine the deceptive displacement according to the speed of the UAV: assuming the displacement vector of the UAV to is: wherein is the maximum flight speed of the UAV; Step (4), obtaining the position of the spoofing point according to the displacement vector and the preset path of the UAV time position , obtaining the position of the spoofing point : ； That is At the moment, the UAV thinks it is The UAV advances according to the displacement vector determined in step (3) forward, achieving the purpose of deception; Step (5), judging whether the position of the spoofing point obtained in step (4) is reasonable, if considering that the position of the spoofing point is reasonable, and the time delay information is obtained, jumping to step (7), if considering that the position of the spoofing point is unreasonable, executing step (6) to re-plan; Step (6), when judging that the position of the spoofing point is unreasonable, performing back-off processing, and jumping to step (5) after the processing is completed; Step (7), generating a spoofing signal according to the time delay information solved in step (5) and sending the spoofing signal to the unmanned aerial vehicle; Step (8), judging the real position whether in the target area, if in the target area, the signal of shooting down or capturing the unmanned aerial vehicle is sent, if not, jump to step (2) until the preset track processing is completed; In step (5), whether the position of the spoofing point is reasonable is judged, specifically comprising: Constructing the following linear programming problem: obtaining a time delay equation group according to a real position pseudo-range equation group and a spoofing point position pseudo-range equation group, constructing a constraint equation group combining with a clock difference constraint condition, and solving a minimum value of a time delay sum of the time delay equation group under the constraint of the constraint equation group; if there is a solution, it is considered that the position of the spoofing point is reasonable; if there is no solution, it is considered that the position of the spoofing point is unreasonable. 2.The method of claim 1, wherein, In step (6), the back-off processing specifically comprises: Obtaining the position of the spoofing point at k moment: ； correcting the drone flight direction and speed, wherein the drone flight direction vector at the time instant is ； Unmanned aerial vehicle flight speed: ； wherein real displacement vector , updating the real position at the next time , k = k + 1. 3.The method of claim 1, wherein, a value of 0.15 km / s; a value of 0.1 km / s.

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