A covert deception method for integrated navigation system

Abstract

The application relates to a concealed deception method for a tightly-coupled navigation system. The method comprises the following steps: constructing a concealed step-type deception signal model after deducing an innovation error model and a state estimation error model by using an INS / GNSS tightly-coupled navigation system model, a Kalman filter model and a step-type deception signal model; optimizing the concealed step-type deception signal model; obtaining the maximum position deception amount that can be exerted by single deception under the condition of satisfying a concealed constraint by using the optimal concealed step-type deception signal model; generating a deception strategy of concealed deception by the maximum position deception amount and a total position deception amount obtained in advance; and generating a step-type deception signal according to the deception strategy to perform concealed deception on a target to be deceived. The method can improve the deception success rate of the tightly-coupled navigation system of an unmanned platform.

Description

Technical Field

[0001] This application relates to the fields of anti-unmanned platform technology and navigation technology, and in particular to a covert deception method for tightly integrated navigation systems. Background Technology

[0002] In recent years, with the rapid development of unmanned technology and the reduction in the cost of unmanned platforms, these platforms have gradually become part of people's daily lives. While bringing convenience, they have also brought new risks and hidden dangers, such as criminals using unmanned platforms to engage in illegal activities or unmanned platforms entering no-fly zones. In such cases, GNSS deception technology is needed to effectively counter illegal unmanned platforms. However, due to the development of GNSS anti-deception technology, most unmanned platforms utilize their own inertial systems to achieve GNSS deception detection and countermeasures. Therefore, conventional GNSS deception techniques are difficult to achieve the desired deception effect, resulting in a low success rate. Summary of the Invention

[0003] Therefore, it is necessary to provide a covert deception method for compactly integrated navigation systems that can improve the success rate of deceiving unmanned platform compactly integrated navigation systems, addressing the aforementioned technical problems.

[0004] A covert deception method for tightly integrated navigation systems, the method comprising:

[0005] Construct a compact INS / GNSS navigation system model for the target to be deceived;

[0006] Using the INS / GNSS tightly integrated navigation system model, Kalman filter model, and step-type deception signal model, the innovation error model and state estimation error model after the target to be deceived are derived; both the innovation error model and the state estimation error model include the step-type deception signal model.

[0007] A concealed step-type deception signal model is constructed using the innovation error model and the state estimation error model. The concealed step-type deception signal model is then optimized using an ergonomic algorithm to obtain the optimal concealed step-type deception signal model.

[0008] The maximum position deception amount that can be applied in a single deception under the condition of satisfying the concealment constraint is obtained by using the optimal concealment step deception signal model.

[0009] A covert deception strategy is generated based on the maximum amount of location deception that can be applied in a single deception and the total amount of location deception that needs to be deceived in advance.

[0010] Based on the deception strategy, a step-type deception signal is generated to covertly deceive the target.

[0011] In one embodiment, the innovation error model and state estimation error model of the target after being deceived are derived using an INS / GNSS tightly integrated navigation system model, a Kalman filter model, and a step-type deception signal model, including:

[0012] Using the INS / GNSS tightly integrated navigation system model, Kalman filter model, and step-type deception signal model, the innovation error model after the target is deceived is derived as follows:

[0013]

[0014] in, H represents the information error caused by deception at time k+n. k+n Let I represent the observation matrix of the Kalman filter at time k+n, where I is the identity matrix and Φ is the distance from the Kalman filter to the Kalman filter. k+n-1 Let K represent the state transition matrix of the Kalman filter at time k+n-1. k+n-1 Let Δz represent the gain matrix of the Kalman filter at time k+n-1. k+n Let be the deception amount of the step-type deception signal in the observation vector at time k+n, where n represents the total number of deception times, k represents any time between the initial and final deception times, k+n represents the final deception time, and i is the number of visible satellites.

[0015] Using the INS / GNSS tightly integrated navigation system model, Kalman filter model, and step-type deception signal model, the state estimation error model of the target after being deceived is derived as follows:

[0016]

[0017] in, Let α and β represent the state estimation error caused by deception at time k+n. l The constant coefficient is l, which represents a counter variable. The offset caused by the deception interference of the GNSS signal at time k.

[0018] In one embodiment, a covert step-type deception signal model is constructed using an innovation error model and a state estimation error model, including:

[0019] A concealed step-type deception signal model is constructed using the innovation error model and the state estimation error model.

[0020]

[0021] Where T0, T are the set deception detection thresholds, and T = [T1…T] 17 ], q k+nFor the normalized sum of squares of the innovation error, Indicates the amount of pseudo-distance deception. This represents the pseudorange rate deception quantity. This represents the maximum pseudorange deception that satisfies the constraints. This represents the maximum pseudorange rate deception that satisfies the constraints.

[0022] In one embodiment, the maximum position deception amount that can be applied in a single deception under the condition of satisfying the concealment constraint is obtained by using the optimal concealment step deception signal model, including:

[0023] Using the optimal concealment step-type deception signal model, the maximum position deception amount that can be applied in a single deception under the condition of concealment constraint is calculated as follows:

[0024]

[0025] Where Δx, Δy, and Δz are the position deception amounts applied along the X, Y, and Z axes, respectively, and R... E Let λ represent the radius of curvature of the circumpolar region, h represent altitude, L represent latitude, and λ represent longitude. This represents the amount of deception applied in the X-axis direction, obtained in the ECEF coordinate system. This represents the amount of deception applied in the Y-axis direction, obtained in the ECEF coordinate system. This represents the amount of deception applied in the Z-axis direction in the ECEF coordinate system, and e represents the ellipsoidal eccentricity.

[0026] In one embodiment, a covert deception strategy is generated based on the maximum amount of location deception that can be applied in a single deception and the pre-acquired total amount of location deception required, including:

[0027] Using the total position deception amount ΔP that needs to be deceived e =(Δx) e ,Δy e ,Δz e The maximum positional deception amount that can be applied in a single deception is ΔP = (Δx, Δy, Δz). The deception control strategy is (N, M) = divmod(ΔP). e ,ΔP); where N represents the number of times deception is required, M represents the amount of deception applied in the last deception, and divmod() represents the deception strategy function;

[0028] Taking the X-axis as an example, when N=0 and M=0, there is no deception; when N=0 and M≠0, one deception of amount M is performed; when N≠0 and M=0, N deceptions of amount Δx are performed; when N≠0 and M≠0, N deceptions of amount Δx are performed, followed by one deception of amount M.

[0029] In one embodiment, generating a step-type deception signal according to a deception strategy to covertly deceive the target includes:

[0030] Based on the deception strategy, a step deception signal is generated to deceive the integrated navigation system. The deception results in the amount of pseudorange deception that needs to be applied to the pseudorange measurement of the original GNSS deception signal and the amount of pseudorange rate deception that needs to be applied to the pseudorange rate measurement of the original GNSS deception signal.

[0031] The GNSS deception signal, with added pseudorange deception amount and pseudorange rate deception amount, is used to deceive the target to be deceived.

[0032] In one embodiment, the pseudorange deception amount to be applied to the original GNSS deception signal measurement pseudorange is:

[0033]

[0034] in, The time when the satellite signal was transmitted. The moment when the satellite signal is captured by the receiver. Let be the position of the i-th satellite in the ECEF coordinate system at the time the satellite signal is transmitted. Let be the position of the i-th satellite in the ECEF coordinate system at the moment the satellite signal is acquired by the receiver. Let be the position deception amount applied by the i-th satellite in the ECEF coordinate system at the moment when the satellite signal is captured by the receiver.

[0035] In one embodiment, the pseudorange rate deception amount to be applied to the original GNSS deception signal measurement pseudorange rate is:

[0036]

[0037] in, Let be the velocity of the i-th satellite in the ECEF coordinate system at the moment the satellite signal is transmitted. Let be the velocity of the i-th satellite in the ECEF coordinate system at the moment the satellite signal is acquired by the receiver. This represents the line-of-sight vector after the deception.

[0038] The aforementioned method for covert deception in tightly integrated navigation systems involves constructing an INS / GNSS tightly integrated navigation system model of the target to be deceived. Then, using this model, along with a Kalman filter model and a step-type deception signal model, the invention derives the innovation error model and state estimation error model resulting from the deception. Next, a covert step-type deception signal model is constructed using these models. An optimal covert step-type deception signal model is obtained by optimizing this model using an ergonomic algorithm. Finally, the maximum position deception amount that can be applied in a single deception while satisfying the covertness constraints is calculated using this optimal model. The maximum position deception amount that can be applied in a single deception and the pre-obtained position deception signal model are then used to determine the optimal model. The system generates a covert deception strategy based on the total position deception amount required for deception. Finally, a step-type deception signal is generated based on the deception strategy to covertly deceive the target. The deception signal and deception control strategy are adjusted in real time according to the deception effect until the target is deceived to the desired deception coordinate point. By designing the deception signal, the impact of the deception signal on the information and state estimation error output is reduced, thereby rendering the deception detector of the target ineffective, thus achieving the purpose of covert deception. It can effectively reduce the deception detection and anti-deception performance of the unmanned platform integrated navigation system, improve the success rate of deception against the unmanned platform integrated navigation system, and improve the effect of anti-unmanned platform. It has a wide range of applications and can be used in drug enforcement and counter-terrorism, protection of key facilities, police security, key area security defense, anti-unmanned combat, and other scenarios with anti-unmanned needs. Attached Figure Description

[0039] Figure 1 This is a schematic diagram illustrating an application scenario of a covert deception method for a tightly integrated navigation system in one embodiment.

[0040] Figure 2 This is a flowchart illustrating a covert deception method for a tightly integrated navigation system in one embodiment. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0042] This application provides a covert deception method for tightly integrated navigation systems, which can be applied to, for example... Figure 1 The application environment shown.

[0043] In one embodiment, such as Figure 2As shown, a covert deception method for tightly integrated navigation systems is provided, comprising the following steps:

[0044] Step 202: Construct an INS / GNSS tightly integrated navigation system model of the target to be deceived.

[0045] A 15-dimensional state vector is constructed by selecting the velocity error, attitude error, and position error of the inertial navigation system, as well as the zero bias of the gyroscope and accelerometer. A 2-dimensional state vector is constructed by selecting the clock error and clock drift of the satellite navigation system receiver. Based on the 15-dimensional state vector, the 2-dimensional state vector, the measurement noise corresponding to the inertial navigation system, and the measurement noise corresponding to the satellite navigation system receiver, a compactly integrated navigation state equation is constructed. The difference between the pseudorange and pseudorange rate measured by the inertial navigation system and the satellite navigation system is selected as the observation quantity to construct the compactly integrated navigation observation equation. The INS / GNSS compactly integrated navigation system model for the target to be deceived is an existing model and will not be elaborated upon in this patent.

[0046] Step 204: Using the INS / GNSS tightly integrated navigation system model, Kalman filter model, and step-type deception signal model, the innovation error model and state estimation error model of the target to be deceived are derived; the innovation error model and state estimation error model include the step-type deception signal model.

[0047] Both the Kalman filter model and the step-type spoofing signal model are existing technologies, and their construction process will not be described in detail in this application.

[0048] Step 206: Construct a concealed step deception signal model using the innovation error model and the state estimation error model. Optimize the concealed step deception signal model using an ergonomic algorithm to obtain the optimal concealed step deception signal model.

[0049] Step 208: Calculate the maximum position deception amount that can be applied in a single deception under the condition of satisfying the concealment constraint using the optimal concealment step deception signal model. Generate a concealment deception strategy based on the maximum position deception amount that can be applied in a single deception and the total position deception amount that needs to be deceived in advance.

[0050] Step 210: Generate a step-type deception signal according to the deception strategy to covertly deceive the target to be deceived.

[0051] This application generates a step deception signal based on a deception strategy to deceive the integrated navigation system. The deception strategy involves determining the pseudorange deception amount to be applied to the original GNSS deception signal's pseudorange measurement and the pseudorange rate deception amount to be applied to the original GNSS deception signal's pseudorange rate measurement. The target is then deceived using the GNSS deception signal with the added pseudorange and pseudorange rate deception amounts. The deception signal and deception control strategy are adjusted in real time based on the deception effect until the target is deceived to the desired deception coordinates. This application designs the deception signal to reduce its impact on innovation and state estimation errors, thereby disabling the target's deception detector and achieving covert deception.

[0052] In the aforementioned method for covert deception of tightly integrated navigation systems, this invention constructs an INS / GNSS tightly integrated navigation system model of the target to be deceived. Then, using the constructed INS / GNSS tightly integrated navigation system model, Kalman filter model, and step-type deception signal model, it derives the innovation error model and state estimation error model caused by the deception after the target is deceived. Next, it constructs a covert step-type deception signal model using the innovation error model and state estimation error model. An ergodic algorithm is used to optimize the covert step-type deception signal model to obtain the optimal covert step-type deception signal model. Using the optimal covert step-type deception signal model, it calculates the maximum position deception amount that can be applied in a single deception while satisfying the covertness constraints. The maximum position deception amount that can be applied in a single deception and the pre-obtained... The system generates a covert deception strategy based on the total position deception amount required for deception. Finally, a step-type deception signal is generated based on the deception strategy to covertly deceive the target. The deception signal and deception control strategy are adjusted in real time according to the deception effect until the target is deceived to the desired deception coordinate point. By designing the deception signal, the impact of the deception signal on information and state estimation errors is reduced, thereby rendering the deception detector of the target ineffective, thus achieving the purpose of covert deception. It can effectively reduce the deception detection and anti-deception performance of the unmanned platform integrated navigation system, improve the success rate of deception against the unmanned platform integrated navigation system, and improve the effectiveness of anti-unmanned platform operations. It has a wide range of applications and can be used in drug enforcement and counter-terrorism, protection of key facilities, police security, key area security defense, anti-unmanned combat, and other scenarios with anti-unmanned needs.

[0053] In one embodiment, constructing an INS / GNSS tightly integrated navigation system model of the target to be deceived includes:

[0054] A 15-dimensional state vector is constructed by selecting the velocity error, attitude error, position error of the inertial navigation system, and the zero bias of the gyroscope and accelerometer. A 2-dimensional state vector is constructed by selecting the clock error and clock drift of the satellite navigation system receiver. A compact combination navigation state equation is constructed based on the 15-dimensional state vector, the 2-dimensional state vector, the measurement noise corresponding to the inertial navigation system, and the measurement noise corresponding to the satellite navigation system receiver.

[0055] The difference between the pseudorange and pseudorange rate measured by the inertial navigation system and the satellite navigation system is selected as the observation to construct the compact combination navigation observation equation.

[0056] In a specific embodiment, the velocity error, attitude error, and position error of the inertial navigation system, as well as the zero bias of the gyroscope and accelerometer, are selected to construct a 15-dimensional state vector X. INS The measurement noise corresponding to the inertial navigation system is W. INS A 2D state vector X is constructed by selecting the clock bias and clock drift of the satellite navigation system receiver. GNSS The measurement noise corresponding to the satellite navigation system receiver is W. GNSS Then we have:

[0057]

[0058] The state equation of the INS / GNSS tightly integrated navigation system is:

[0059]

[0060] The difference between the pseudorange and pseudorange rate measured by the inertial navigation system and the satellite navigation system is taken as the observation quantity Z, and the corresponding observation noise is V; if there are i visible satellites, then:

[0061]

[0062]

[0063] The observation equations for the tightly integrated INS / GNSS navigation system are as follows:

[0064] Z = HX + V

[0065] In one embodiment, the innovation error model and state estimation error model of the target after being deceived are derived using an INS / GNSS tightly integrated navigation system model, a Kalman filter model, and a step-type deception signal model, including:

[0066] Using the INS / GNSS tightly integrated navigation system model, Kalman filter model, and step-type deception signal model, the innovation error model after the target is deceived is derived as follows:

[0067]

[0068] in, H represents the information error caused by deception at time k+n. k+n Let I represent the observation matrix of the Kalman filter at time k+n, where I is the identity matrix and Φ is the distance from the Kalman filter to the Kalman filter. k+n-1 Let K represent the state transition matrix of the Kalman filter at time k+n-1. k+n-1 Let Δz represent the gain matrix of the Kalman filter at time k+n-1. k+n Let be the deception amount of the step-type deception signal in the observation vector at time k+n, where n represents the total number of deception times, k represents any time between the initial and final deception times, k+n represents the final deception time, and i is the number of visible satellites.

[0069] Using the INS / GNSS tightly integrated navigation system model, Kalman filter model, and step-type deception signal model, the state estimation error model of the target after being deceived is derived as follows:

[0070]

[0071] in, Let α and β represent the state estimation error caused by deception at time k+n. l The constant coefficient is l, which represents a counter variable. Let r be the offset caused by the deception interference of the GNSS signal at time k, and r and the corresponding state variables take values ​​from 1 to 17.

[0072] In a specific embodiment, assuming that the GNSS signal is deceived at any initial deception moment by adding a deception amount to the pseudorange and pseudorange rate of the GNSS signal, and that at time k0 the GNSS deception signal locks the tracking loop of the deceiving target receiver, then:

[0073]

[0074] in and The pseudorange and pseudorange rate received by the satellite receiver after the GNSS signal has been spoofed. and The pseudorange and pseudorange rate received by the satellite receiver when the GNSS signal is not spoofed. and The pseudorange and pseudorange rate spoofing offset applied to the GNSS spoofing signal.

[0075] This application uses a step-spoofing signal offset model as...

[0076]

[0077] in Apply a deception offset to GNSS deception.

[0078] The offset caused by deception interference of the GNSS signal at time k. for:

[0079]

[0080] In one embodiment, a covert step-type deception signal model is constructed based on the innovation error model and the state estimation error model, including:

[0081] The constructed covert step-type deception signal model is as follows:

[0082]

[0083] Where T0, T are the set deception detection thresholds, and T = [T1…T] 17 ], q k+n For the normalized sum of squares of the innovation error, Indicates the amount of pseudo-distance deception. This represents the pseudorange rate deception quantity. This represents the maximum pseudorange deception that satisfies the constraints. This represents the maximum pseudorange rate deception that satisfies the constraints.

[0084] In one embodiment, the maximum position deception amount that can be applied in a single deception under the condition of satisfying the concealment constraint is obtained by using the optimal concealment step deception signal model, including:

[0085] Using the optimal concealment step-type deception signal model, the maximum position deception amount that can be applied in a single deception under the condition of concealment constraint is calculated as follows:

[0086]

[0087] Where Δx, Δy, and Δz are the position deception amounts applied along the X, Y, and Z axes, respectively, and R... E Let λ represent the radius of curvature of the circumpolar region, h represent altitude, L represent latitude, and λ represent longitude. This represents the position deception amount applied in the X-axis direction, obtained in the ECEF coordinate system. This represents the amount of position deception applied in the Y-axis direction, obtained in the ECEF coordinate system. This represents the position deception applied in the Z-axis direction in the ECEF coordinate system, and e represents the ellipsoidal eccentricity.

[0088] In a specific embodiment, the velocity deception offset that satisfies the concealment constraint is:

[0089]

[0090] in, These are the velocity deception amounts applied along the X, Y, and Z axes, respectively. This represents the velocity deception applied along the X-axis in the ECEF coordinate system. This represents the velocity deception applied along the Y-axis in the ECEF coordinate system. This represents the velocity deception applied in the Z-axis direction as obtained in the ECEF coordinate system.

[0091] In one embodiment, a covert deception strategy is generated based on the maximum amount of location deception that can be applied in a single deception and the pre-acquired total amount of location deception required, including:

[0092] Using the total position deception amount ΔP that needs to be deceived e =(Δx) e ,Δy e ,Δz e The maximum positional deception amount that can be applied in a single deception is ΔP = (Δx, Δy, Δz). The deception control strategy is (N, M) = divmod(ΔP). e ,ΔP); where N represents the number of times deception is required, M represents the amount of deception applied in the last deception, and divmod() represents the deception strategy function;

[0093] Taking the X-axis as an example, when N=0 and M=0, there is no deception; when N=0 and M≠0, one deception of amount M is performed; when N≠0 and M=0, N deceptions of amount Δx are performed; when N≠0 and M≠0, N deceptions of amount Δx are performed, followed by one deception of amount M.

[0094] In one embodiment, generating a step-type deception signal according to a deception strategy to covertly deceive the target includes:

[0095] Based on the deception strategy, a step deception signal is generated to deceive the integrated navigation system. The deception results in the amount of pseudorange deception that needs to be applied to the pseudorange measurement of the original GNSS deception signal and the amount of pseudorange rate deception that needs to be applied to the pseudorange rate measurement of the original GNSS deception signal.

[0096] The GNSS deception signal, with added pseudorange deception amount and pseudorange rate deception amount, is used to deceive the target to be deceived.

[0097] In one embodiment, the pseudorange deception amount to be applied to the original GNSS deception signal measurement pseudorange is:

[0098]

[0099] in, The time when the satellite signal was transmitted. The moment when the satellite signal is captured by the receiver. Let be the position of the i-th satellite in the ECEF coordinate system at the time the satellite signal is transmitted. Let be the position of the i-th satellite in the ECEF coordinate system at the moment the satellite signal is acquired by the receiver. Let be the position deception amount applied by the i-th satellite in the ECEF coordinate system at the moment when the satellite signal is captured by the receiver.

[0100] In one embodiment, the pseudorange rate deception amount to be applied to the original GNSS deception signal measurement pseudorange rate is:

[0101]

[0102] in, Let be the velocity of the i-th satellite in the ECEF coordinate system at the moment the satellite signal is transmitted. Let be the velocity of the i-th satellite in the ECEF coordinate system at the moment the satellite signal is acquired by the receiver. This represents the line-of-sight vector after the deception.

[0103] It should be understood that, although Figure 1 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 1 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0104] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0105] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A stealthy deception method for a tightly coupled navigation system, characterized in that, The method comprises: constructing an INS / GNSS tightly coupled navigation system model of a target to be spoofed; deriving, by using the INS / GNSS tightly coupled navigation system model, a Kalman filter model and a step-type spoofing signal model, an innovation error model and a state estimation error model of the target to be spoofed after being spoofed; the innovation error model and the state estimation error model both comprise the step-type spoofing signal model; constructing a stealthy step-type spoofing signal model by using the innovation error model and the state estimation error model, and optimizing the stealthy step-type spoofing signal model by using an exhaustive algorithm to obtain an optimal stealthy step-type spoofing signal model; obtaining a maximum position spoofing amount that can be applied by single spoofing under a stealthy constraint condition by using the optimal stealthy step-type spoofing signal model; generating a spoofing strategy of stealthy spoofing according to the maximum position spoofing amount that can be applied by single spoofing and a total position spoofing amount to be spoofed obtained in advance; spoofing the target to be spoofed by generating a step-type spoofing signal according to the spoofing strategy.

2. The method of claim 1, wherein, The method for deriving, by using the INS / GNSS tightly coupled navigation system model, the Kalman filter model and the step-type spoofing signal model, the innovation error model and the state estimation error model of the target to be spoofed after being spoofed comprises: The method for deriving, by using the INS / GNSS tightly coupled navigation system model, the Kalman filter model and the step-type spoofing signal model, the innovation error model of the target to be spoofed after being spoofed comprises: ； in, express Information errors caused by deception at all times. Indicates that the Kalman filter is in The observation matrix at time, It is the identity matrix. Indicates that the Kalman filter is in The state transition matrix at time t, Indicates that the Kalman filter is in Gain matrix at time step for The amount of deception in the step-type deception signal in the time-observation vector. n This represents the total number of moments of deception. k This represents any point in time between the initial and final moments of the deception. This signifies the final moment of deception. i It is the number of visible satellites; The method for deriving, by using the INS / GNSS tightly coupled navigation system model, the Kalman filter model and the step-type spoofing signal model, the state estimation error model of the target to be spoofed after being spoofed comprises: ； wherein, denotes the state estimation error due to spoofing at time k, and is a constant coefficient, l denotes a score variable, is an offset caused by spoofing interference of GNSS signals at time k, r corresponding to the state variable, respectively, take 1~17.

3. The method of claim 2, wherein, The method for constructing the stealthy step-type spoofing signal model by using the innovation error model and the state estimation error model comprises: The method for constructing the stealthy step-type spoofing signal model by using the innovation error model and the state estimation error model is: ； wherein is a set spoofing detection threshold, , is a normalized sum of innovation errors, denotes a pseudorange spoofing amount, denotes a pseudorange rate spoofing amount, denotes a maximum pseudorange spoofing amount satisfying a constraint condition, denotes a maximum pseudorange rate spoofing amount satisfying a constraint condition.

4. The method of claim 3, wherein, The method for obtaining the maximum position spoofing amount that can be applied by single spoofing under the stealthy constraint condition by using the optimal stealthy step-type spoofing signal model comprises: The method for obtaining the maximum position spoofing amount that can be applied by single spoofing under the stealthy constraint condition by using the optimal stealthy step-type spoofing signal model is: ； wherein, respectively the position spoofing amount applied in X, Y, Z axis, denotes the radius of curvature of the prime vertical, denotes the altitude, denotes the latitude, denotes the longitude, denotes the spoofing amount applied in X axis direction derived in ECEF coordinate system, denotes the spoofing amount applied in Y axis direction derived in ECEF coordinate system, denotes the spoofing amount applied in Z axis direction derived in ECEF coordinate system, denotes the ellipsoid eccentricity.

5. The method of claim 4, wherein, The method for generating the spoofing strategy of stealthy spoofing according to the maximum position spoofing amount that can be applied by single spoofing and the total position spoofing amount to be spoofed obtained in advance comprises: total amount of position spoofing required maximum amount of position spoofing that can be applied by a single spoof generating a spoof control strategy for where N represents the number of times spoofing is required, M represents the amount of spoofing applied by the last spoof, represents a spoof strategy function.

6. The method of claim 5, wherein, The method for spoofing the target to be spoofed by generating the step-type spoofing signal according to the spoofing strategy comprises: According to the spoofing strategy, a step-type spoofing signal is generated to spoof the target to be spoofed. According to the spoofing strategy, a step-type spoofing signal is generated to spoof the target to be spoofed.

7. The method of claim 6, wherein, According to the spoofing strategy, a step-type spoofing signal is generated to spoof the target to be spoofed. The pseudo-range spoofing amount to be applied on the original GNSS spoofing signal measurement pseudo-range is: The pseudo-range spoofing amount to be applied on the original GNSS spoofing signal measurement pseudo-range is: ； in, The time when the satellite signal was transmitted. The moment when the satellite signal is captured by the receiver. For the first i The position of each satellite in the ECEF coordinate system at the time the satellite signal was transmitted. For the first i The position of each satellite in the ECEF coordinate system at the moment its signal is acquired by the receiver. For the first i The position deception amount applied by a satellite in the ECEF coordinate system at the moment the satellite signal is captured by the receiver.

8. The method of claim 7, wherein, The pseudo-range rate spoofing quantity required to be imposed on the original GNSS spoofing signal measurement pseudo-range rate is: ； wherein, is the first i the velocity of the i-th satellite in the ECEF coordinate system at the time of transmission of the satellite signal, is the first i the velocity of the i-th satellite in the ECEF coordinate system at the time of reception of the satellite signal by the receiver, denotes the spoofed line-of-sight vector.

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