Navigation deception jamming time delay design method for illegal unmanned aerial vehicle trapping

Abstract

The invention discloses a navigation deception jamming time delay design method for illegal unmanned aerial vehicle trapping. The navigation deception jamming time delay design method comprises the following steps: S1, acquiring position coordinates required for time delay calculation; s2, calculating a theoretical position calculated by an illegal unmanned aerial vehicle after the time delay of each satellite through a Newton iteration method, and calculating a three-dimensional coordinate after the time delay; s3, subtracting the current actual coordinate from the calculated theoretical coordinate, and then dividing by the time delay to obtain a unit time delay coordinate change vector of each satellite; s4, establishing an equation set about a time delay vector, and solving the time delay vector by using a least square method; and S5, subtracting the minimum value in the time delay vector from the time delay vector to obtain a time delay value required to be configured for each satellite. According to the method, the time delay value of each satellite is calculated, and then corresponding time delay is carried out, so that the target is deceived to the set position.

Description

Technical Field

[0001] The present invention relates to the field of navigation jamming, and in particular to a navigation deception jamming delay design method for trapping illegal unmanned aerial vehicles. Background Art

[0002] In recent years, drones have been widely used in communication, monitoring, photography and other fields due to their small size and low cost. However, drones can directly attack people and public facilities, and can also spy on private information by taking pictures or videos. Therefore, illegal drones pose a great security threat, and it is very important to study how to capture illegal drones. One of the capture methods is to guide the target illegal drone to the desired location by forwarding navigation deception interference signals. However, if the combined signals of all satellites are directly forwarded with a unified delay, the target positioning cannot be changed, and the target cannot be deceived to the desired location. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a navigation deception interference delay design method for illegal drone trapping. By calculating the delay value for each satellite and then performing the corresponding delay, the target can be deceived to a set position.

[0004] The object of the present invention is to achieve the following technical solution: a navigation deception jamming delay design method for illegal drone trapping, comprising the following steps:

[0005] S1. Obtain the location coordinates required for delay calculation;

[0006] S2. Calculate the time delay of each satellite through Newton iteration method, calculate the theoretical position of the illegal drone, and calculate the three-dimensional coordinates after the time delay;

[0007] S3. Subtract the current actual coordinates from the calculated theoretical coordinates, and then divide by the delay to obtain the unit delay coordinate change vector of each star;

[0008] S4. Establish a system of equations about the delay vector and solve the delay vector using the least squares method;

[0009] S5. Subtract the minimum value in the delay vector from the delay vector to obtain the delay value required to be configured for each satellite.

[0010] The beneficial effect of the present invention is that the present invention calculates the time delay value for each satellite and then performs a corresponding time delay to deceive the target to a set position. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 Flowchart of the time-delay design method. DETAILED DESCRIPTION

[0012] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings, but the protection scope of the present invention is not limited to the following.

[0013] like Figure 1 As shown, a navigation deception jamming delay design method for illegal drone trapping includes the following steps:

[0014] S1. Obtain the location coordinates required for delay calculation;

[0015] Get the position coordinates needed for delay calculation, including the three-dimensional coordinates of all navigation satellites in the sky at the current moment. Assuming there are N satellites, the coordinates are The actual 3D coordinates of the illegal drone are deceptively w r =[x r ,y r ,z r ] T The three-dimensional coordinates of the spoof signal forwarding platform are w a =[x a ,y a ,z a ] T The three-dimensional coordinates of the intended deceptive position are w q =[x q ,y q ,z q ] T .

[0016] S2. Calculate the time delay of each satellite through Newton iteration method, calculate the theoretical position of the illegal drone, and calculate the three-dimensional coordinates after the time delay;

[0017] Each satellite signal is delayed by a certain amount τ0. The value of τ0 should not be too large or too small. It is usually better to be in the range of 0.01-0.5ms. After calculating the delay of each satellite signal by Newton iteration method, the theoretical three-dimensional coordinates of the illegal drone are calculated as follows:

[0018] For each satellite signal delay, the specific steps of calculating the coordinates using the Newton iteration method are as follows:

[0019] (1) First, the pseudo-range positioning equation without satellite signal delay is given as:

[0020]

[0021] If the nth satellite is delayed, the nth equation in the above equation group becomes:

[0022]

[0023] Before starting the Newton iteration calculation, it is also necessary to give an initial estimate of the current position coordinates of the illegal drone. and an initial estimate of the clock error The initial values ​​are all set to zero;

[0024] (2) For the mth equation in the system of equations, for the function r (m) Find the partial derivative, m = 1, 2, ..., N, and we get

[0025]

[0026] where r (m) for

[0027]

[0028] The left side of each equation in the system of equations is a u It is a linear function of , so its partial derivative is 1.

[0029] k represents the number of iterations currently in progress, k-1 represents the number of iterations that have been completed, k=1 represents the first iteration, and in the kth Newton iteration, each nonlinear equation in the system of equations is Linearization, the matrix equation after linearization is:

[0030]

[0031] in,

[0032]

[0033] For vector b, since the nth satellite signal is delayed, the nth row in b becomes

[0034] (3) Solve the linear equation using the least squares method and obtain the solution:

[0035]

[0036] (4) Update the roots of the nonlinear equations. The updated illegal drone position coordinates and clock error values ​​are:

[0037]

[0038] (5) Determine whether the Newton iteration has converged to the required accuracy; if it has converged to the required accuracy, exit the iteration loop and output the positioning result; otherwise, add 1 to the k value and return to step (2) to perform Newton iteration calculation again; for whether it has converged, the ||Δw|| or ||Δw|| obtained by this iteration calculation is used. Is the value less than the preset threshold?

[0039] S3. Subtract the current actual coordinates from the calculated theoretical coordinates, and then divide by the delay τ0 to obtain the unit delay coordinate change vector of each star. The unit delay coordinate change vector of the nth star is

[0040]

[0041] Then the unit delay variation matrix is

[0042]

[0043] S4. Establish a system of equations about the delay vector and solve the delay vector using the least squares method;

[0044] The target coordinate change vector is obtained by subtracting the current actual coordinate from the proposed deception position coordinate:

[0045]

[0046] Let the unit delay change matrix A multiplied by the delay vector T equal the target coordinate change vector Δ0, AT = Δ0, that is

[0047]

[0048] Using the least squares algorithm to solve the above equations, we can get the delay vector T as

[0049] T=(A T A) -1 A T Δ0

[0050] S5. Subtract the minimum value in the delay vector from the delay vector to obtain the delay value required to be configured for each satellite.

[0051] In order to reduce the change of clock error after deception and avoid negative delay, the minimum element value in the delay vector T is recorded as t min , let T'=Tt min , if t min ≥0, reduce the clock difference jump; if t min <0, making it feasible in engineering; T'=[τ1',τ'2,…,τ' N ] T This is the delay value that we finally calculated that needs to be configured for each satellite.

[0052] In the embodiments of the present application, simulation analysis and evaluation are performed on the proposed delay design method.

[0053] Table 1 Simulated satellite coordinates

[0054]

[0055] Table 2 Simulation coordinates of each point

[0056]

[0057] Table 3 Delay algorithm simulation results

[0058]

[0059] Table 3 shows the delay values ​​of each navigation signal calculated according to the delay design method, as well as the final positioning result value of the illegal drone after receiving the delay spoofing signal. It can be seen that the error distance between the spoofed positioning result and the set intended spoofed position is only 0.4330m, and the relative error is only 0.0379%. The delay design method proposed in this patent is feasible in engineering, and the spoofing error is small.

[0060] The above is a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in other combinations, modifications and environments, and can be modified within the scope of the concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not depart from the spirit and scope of the present invention, and should be within the scope of protection of the claims attached to the present invention.

Claims

1. A navigation deception jamming delay design method for illegal drone trapping, characterized by: The following steps are involved: S1. Obtain the location coordinates required for delay calculation; S2. Calculate the time delay of each satellite through Newton iteration method, calculate the theoretical position of the illegal drone, and calculate the three-dimensional coordinates after the time delay; S3. Subtract the current actual coordinates from the calculated theoretical coordinates, and then divide by the delay to obtain the unit delay coordinate change vector of each star; S4. Establish a system of equations about the delay vector and solve the delay vector using the least squares method; S5. Subtract the minimum value in the delay vector from the delay vector to obtain the delay value required to be configured for each satellite.

2. According to claim 1, a navigation deception jamming delay design method for trapping illegal drones is characterized by: The position coordinates required for delay calculation in step S1 include: The three-dimensional coordinates of all navigation satellites in the sky at the current moment, assuming there are N satellites, are: The actual 3D coordinates of the illegal drone are deceptively w r =[x r ,y r ,z r ] T ; The three-dimensional coordinates of the spoof signal forwarding platform are w a =[x a ,y a ,z a ] T ; The three-dimensional coordinates of the intended deceptive position are w q =[x q ,y q ,z q ] T .

3. According to claim 1, a navigation deception jamming delay design method for trapping illegal drones is characterized by: The step S2 comprises: Each satellite signal is delayed by a certain time τ0. After calculating the delay of each satellite signal by Newton iteration method, the theoretical three-dimensional coordinates of the illegal drone are calculated as follows: For each satellite signal delay, the specific steps of calculating the coordinates using the Newton iteration method are as follows: (1) First, the pseudo-range positioning equation without satellite signal delay is given as: If the nth satellite is delayed, the nth equation in the above equation group becomes: Before starting the Newton iteration calculation, it is also necessary to give an initial estimate of the current position coordinates of the illegal drone. and an initial estimate of the clock error The initial values ​​are all set to zero; (2) For the mth equation in the system of equations, for the function r (m) Find the partial derivative, m = 1, 2, ..., N, and we get where r (m) for The left side of each equation in the system of equations is a u It is a linear function of , so its partial derivative is 1. k represents the number of iterations currently in progress, k-1 represents the number of iterations that have been completed, k=1 represents the first iteration, and in the kth Newton iteration, each nonlinear equation in the system of equations is Linearization, the matrix equation after linearization is: in, For vector b, since the nth satellite signal is delayed, the nth row in b becomes (3) Solve the linear equation using the least squares method and obtain the solution: (4) Update the roots of the nonlinear equations. The updated illegal drone position coordinates and clock error values ​​are: (5) Determine whether the Newton iteration has converged to the required accuracy; if it has converged to the required accuracy, exit the iteration loop and output the positioning result; otherwise, add 1 to the k value and return to step (2) to perform Newton iteration calculation again; for whether it has converged, the ||Δw|| or ||Δw|| obtained by this iteration calculation is used. Is the value less than the preset threshold? 4. According to claim 1, a navigation deception jamming delay design method for trapping illegal drones is characterized by: The step S3 comprises: Subtract the current actual coordinates from the calculated theoretical coordinates, and then divide by the delay τ0 to get the unit delay coordinate change vector of each star. The unit delay coordinate change vector of the nth star is Then the unit delay variation matrix is 5. According to claim 1, a navigation deception jamming delay design method for trapping illegal drones is characterized by: The step S4 comprises: The target coordinate change vector is obtained by subtracting the current actual coordinate from the proposed deception position coordinate: Let the unit delay change matrix A multiplied by the delay vector T equal the target coordinate change vector Δ0, AT = Δ0, that is Using the least squares algorithm to solve the above equations, we get the delay vector T as T=(A T A) -1 A T Δ0。 6. The navigation deception jamming delay design method for illegal drone trapping according to claim 1 is characterized by: The step S5 comprises: The smallest element value in the delay vector T is recorded as t min , let T'=Tt min , T'=[τ1',τ'2,…,τ' N ] T That is, the final calculated delay value required to be configured for each satellite.

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