Satellite navigation timing deception interference defense method, device, electronic equipment and medium

Abstract

The present application relates to a method, device, electronic device and medium for defending against deception interference in satellite navigation timing, including: obtaining multiple observation quantities of a satellite and the cumulative length of multiple observation quantities based on satellite signals; estimating new information based on the current satellite's on-orbit motion state, multiple propagation delay correction parameters, pseudorange observation quantities and pseudorange rate observation quantities, and calculating new information constraint parameters; performing deception detection when the cumulative length meets the preset deception detection conditions, and initiating a deception alert to users of GNSS devices using global navigation satellite systems when the result of the deception detection is that a deception attack exists. Thus, the problem that the GNSS deception detection technology in the related art needs to collect GNSS data for a long time to obtain a more reliable detection result is solved, resulting in the deviation of the timing result exceeding the user's acceptable range before the deception signal is detected, and the purpose of improving the security of GNSS timing is achieved.

Description

Technical Field

[0001] The present application relates to the field of satellite navigation and timing technology, and in particular to a method, device, electronic device and medium for preventing satellite navigation and timing deception and interference. Background Art

[0002] Global Navigation Satellite Systems (GNSS), represented by GPS, GLONASS, Galileo, and BeiDou, can provide users with all-weather, all-day positioning, navigation, and timing services. GNSS timing services, which receive and process GNSS signals to obtain high-precision time information, have been widely used in many fields, including electricity, communications, and finance. Currently, GNSS users can directly obtain high-precision time information by receiving and processing navigation satellite signals, or they can use GNSS time to discipline local clocks such as crystal oscillators and atomic clocks and then obtain time output based on these local clocks. These applications all fall within the scope of GNSS timing.

[0003] On the other hand, the security of GNSS timing services faces significant challenges due to GNSS spoofing attacks. If a spoofing attack occurs, the time calculation results of user terminals are likely to be tampered with, resulting in users receiving erroneous time information. This can have serious consequences. For example, power systems rely on GNSS timing services for network synchronization and grid dispatch and control. If a spoofing attack occurs, the time information output by the GNSS is incorrect. Misled by this erroneous time information, the power grid may perform irrational operations and controls, leading to dangerous events such as network failures and crashes. Therefore, effectively defending against spoofing attacks is extremely urgent and important.

[0004] To defend against spoofing, a large number of GNSS spoofing detection technologies have emerged in recent years. These include signal power detection, signal quality monitoring, Doppler positioning consistency detection, and extended receiver autonomous integrity monitoring. However, since GNSS timing devices are generally stationary, spoofing attacks can simulate real signals with high fidelity. Without changing the target's positioning information, these attacks can exploit the target device's internal signal tracking loop to achieve gradual time manipulation without causing a jump in the timing result, significantly increasing the attack's stealth. This type of attack is known as a gradual timing spoofing attack. Existing GNSS spoofing detection technologies require a long period of GNSS data collection to obtain reliable detection results. Consequently, by the time the spoofing detection module detects a spoofing attack, the timing result is often already significantly skewed. Users are already using severely erroneous timing results before the spoofing attack is discovered, posing a significant security risk. Summary of the Invention

[0005] The present application provides a method, device, electronic device and medium for defending against satellite navigation timing deception interference, so as to solve the problem that the GNSS deception detection technology in the related art needs to collect GNSS data for a long time to obtain more reliable detection results, resulting in the timing result deviation exceeding the user's acceptable range before the deception signal is detected.

[0006] The first aspect of the present application provides a method for defending against satellite navigation timing deception interference, comprising the following steps: receiving a satellite signal from at least one satellite, and obtaining multiple observation quantities of the at least one satellite and the cumulative length of the multiple observation quantities based on the satellite signal, wherein the multiple observation quantities include a pseudorange observation quantity, a pseudorange rate observation quantity, the satellite's on-orbit motion state at the current moment from the satellite ephemeris, and multiple propagation delay correction parameters at the current moment from the satellite ephemeris; performing new information estimation based on the satellite's on-orbit motion state at the current moment, the multiple propagation delay correction parameters at the current moment, the pseudorange observation quantity, and the pseudorange rate observation quantity, and calculating new information constraint parameters; judging whether the cumulative length meets a preset deception detection condition, and performing deception detection when the cumulative length meets the preset deception detection condition, and initiating a deception alert to a user using a global navigation satellite system (GNSS) device when the result of the deception detection is that a deception attack exists.

[0007] Optionally, after determining that the cumulative length does not meet a preset deception detection condition, updating the local clock state vector and various filter state parameters based on a preset first update strategy;

[0008] The preset first update strategy is:

[0009] b←b+αKγ

[0010] r←(I-KH)Ar+(1-α)Kγ

[0011]

[0012]

[0013]

[0014] n←n+1

[0015] Among them, ← is the assignment operator, b is the local clock state vector, K is the gain matrix, γ is the observation innovation, r is the cumulative amount of innovation constraint, I is the 2K-order unit matrix, Δt is the time interval between two observations, (1 and 0 are all-1 and all-0 column vectors of length K respectively), c is the speed of light, is the cumulative clock drift change, b ais the cumulative clock bias change, B is the maximum clock bias change, e1 = [1, 0], e2 = [0, 1], B0 is the timing safety margin, L is the measurement length, n is the iteration counter, and |·| is the absolute value of the calculated scalar.

[0016] Optionally, after determining that the cumulative length meets a preset spoofing detection condition and performing spoofing detection, the method further includes: if the spoofing result is that the spoofing attack does not exist, updating the local clock state vector based on a preset second update strategy, and then initializing the clock filter parameters according to a preset initialization strategy; wherein the preset second update strategy is:

[0017] b←b+Kγ+(I-KH)Ar;

[0018] The preset initialization strategy is:

[0019] r←0

[0020]

[0021] b a ←0.

[0022] B←B0 / (LΔt)

[0023] n←1

[0024] Optionally, the estimation and calculation strategy for performing innovation estimation and calculating innovation constraint parameters based on the satellite's on-orbit motion state at the current moment, the multiple propagation delay correction parameters at the current moment, the pseudorange observations, and the pseudorange rate observations is:

[0025]

[0026]

[0027]

[0028]

[0029] M′←AMA T +Q

[0030] K←M′H(C+HM′H T ) -1 ;

[0031] M←(I-KH)M′

[0032]

[0033]

[0034]

[0035] in, is the corrected pseudorange observation of the i-th signal, ρ i is the pseudorange observation, is the corrected pseudorange rate observation of the i-th signal, P u is the position vector, P i is the satellite position vector, c is the speed of light, I i is the total correction for tropospheric and ionospheric delay, b i is the satellite clock bias, is the pseudo-range rate observation, V u is the velocity vector, V i is the velocity vector, is the spatial distance correction observation vector, is the prior estimate of the observation vector at the current moment based on the local clock state at the previous moment, M′ is the prior estimate covariance matrix, M is the posterior estimate covariance matrix, Q is the covariance matrix, β is the intermediate term for calculating the innovation constraint coefficient, β is the intermediate term for calculating the innovation constraint coefficient, α is the innovation constraint parameter, ||·|| represents the modulus of the calculated vector, exp is the natural exponential function, min is the minimum function, and T is the vector or matrix transpose.

[0036] Optionally, the above-mentioned satellite navigation timing spoofing and interference defense method also includes: after updating the local clock state parameters, obtaining the user's timing usage mode of the GNSS; if the timing usage mode is to directly use the time provided by the GNSS, then calculating the current time based on the updated local clock state vector b and the updated clock filter parameters (including the accumulated clock drift change, the accumulated clock bias change, the maximum clock bias change and at least one of the accumulated new information constraints), and directly outputting the current time for the user to use; if the timing usage mode is the local clock taming mode, then calculating the local clock correction parameters based on the updated local clock state vector b and the updated clock filter parameters (including the accumulated clock drift change, the accumulated clock bias change, the maximum clock bias change and at least one of the accumulated new information constraints), taming the local clock based on the local clock correction parameters, and providing the time output by the tamed local clock for the user to use.

[0037] The second aspect of the present application provides a satellite navigation timing deception interference defense device, including: an acquisition module, used to receive satellite signals from at least one satellite, and obtain multiple observation quantities of the at least one satellite and the cumulative length of the multiple observation quantities based on the satellite signals, wherein the multiple observation quantities include pseudorange observation quantities, pseudorange rate observation quantities, the satellite's on-orbit motion state at the current moment from the satellite ephemeris, and multiple propagation delay correction parameters at the current moment from the satellite ephemeris; a calculation module, used to perform new information estimation based on the satellite's on-orbit motion state at the current moment, the multiple propagation delay correction parameters at the current moment, the pseudorange observation quantities and the pseudorange rate observation quantities, and calculate new information constraint parameters; a judgment module, used to judge whether the cumulative length meets a preset deception detection condition, and perform deception detection when the cumulative length meets the preset deception detection condition, and initiate a deception alarm to a user using a global navigation satellite system GNSS device when the result of the deception detection is that a deception attack exists.

[0038] Optionally, after determining that the cumulative length does not meet a preset deception detection condition, the judgment module is further configured to: update the local clock state vector and various filter state parameters based on a preset first update strategy;

[0039] The preset first update strategy is:

[0040] b←b+αKγ

[0041] r←(I-KH)Ar+(1-α)Kγ

[0042]

[0043]

[0044]

[0045] n←n+1

[0046] Among them, ← is the assignment operator, b is the local clock state vector, K is the gain matrix, γ is the observation innovation, r is the cumulative amount of innovation constraint, I is the 2K-order unit matrix, Δt is the time interval between two observations, (1 and 0 are all-1 and all-0 column vectors of length K respectively), c is the speed of light, is the cumulative clock drift change, b a is the cumulative clock bias change, B is the maximum clock bias change, e1 = [1, 0], e2 = [0, 1], B0 is the timing safety margin, L is the measurement length, n is the iteration counter, and |·| is the absolute value of the calculated scalar.

[0047] Optionally, after performing the deception detection, the judgment module is further configured to: if the deception result is that the deception attack does not exist, update the local clock state vector based on a preset second update strategy, and initialize the clock filter parameters according to a preset initialization strategy;

[0048] The preset second update strategy is:

[0049] b←b+Kγ+(I-KH)Ar;

[0050] The preset initialization strategy is:

[0051] r←0

[0052]

[0053] b a ←0.

[0054] B←B0 / (LΔt)

[0055] n←1

[0056] Optionally, the calculation module is further configured to: perform innovation estimation and calculate innovation constraint parameters based on the current satellite on-orbit motion state, the multiple propagation delay correction parameters at the current moment, the pseudorange observations, and the pseudorange rate observations. The estimation and calculation strategy is:

[0057]

[0058]

[0059]

[0060]

[0061] M′←AMA T +Q

[0062] K←M′H(C+HM′H T ) -1 ;

[0063] M←(I-KH)M′

[0064]

[0065]

[0066]

[0067] in, is the corrected pseudorange observation of the i-th signal, ρ i is the pseudorange observation, is the corrected pseudorange rate observation of the i-th signal, P u is the position vector, P i is the satellite position vector, c is the speed of light, I i is the total correction for tropospheric and ionospheric delay, b i is the satellite clock bias, is the pseudo-range rate observation, V u is the velocity vector, V i is the velocity vector, is the spatial distance correction observation vector, is the prior estimate of the observation vector at the current moment based on the local clock state at the previous moment, M′ is the prior estimate covariance matrix, M is the posterior estimate covariance matrix, Q is the covariance matrix, β is the intermediate term for calculating the innovation constraint coefficient, β is the intermediate term for calculating the innovation constraint coefficient, α is the innovation constraint parameter, ||·|| represents the modulus of the calculated vector, exp is the natural exponential function, min is the minimum function, and T is the vector or matrix transpose.

[0068] Optionally, the judgment module is also used to: after updating the local clock state parameters, obtain the user's timing usage mode of the GNSS; if the timing usage mode is to directly use the time provided by the GNSS, then calculate the current time according to the updated local clock state vector b and the updated clock filter parameters (including at least one of the accumulated clock drift change, the accumulated clock bias change, the maximum clock bias change and the accumulated new information constraints), and directly output the current time for the user to use; if the timing usage mode is the local clock taming mode, then calculate the local clock correction parameters according to the updated local clock state vector b and the updated clock filter parameters (including at least one of the accumulated clock drift change, the accumulated clock bias change, the maximum clock bias change and the accumulated new information constraints), tame the local clock based on the local clock correction parameters, and provide the time output by the tamed local clock for the user to use.

[0069] The third aspect of the present application provides an electronic device, including: a memory, a processor, and a computer program stored on the memory and runnable on the processor, wherein the processor executes the program to implement the satellite navigation timing deception interference defense method as described in the above embodiment.

[0070] The fourth aspect of the present application provides a computer-readable storage medium on which a computer program is stored. The program is executed by a processor to implement the satellite navigation timing deception and interference defense method as described in the above embodiment.

[0071] The present application obtains a satellite signal of at least one satellite based on a satellite signal, and obtains multiple observation quantities and a cumulative length of multiple observation quantities of the at least one satellite based on the satellite signal, performs innovation estimation based on the satellite's on-orbit motion state at a current moment, multiple propagation delay correction parameters at a current moment, pseudorange observation quantities, and pseudorange rate observation quantities, and calculates innovation constraint parameters; determines whether the cumulative length meets a preset deception detection condition, performs deception detection when the cumulative length meets the preset deception detection condition, and initiates a deception alert to a user of a global navigation satellite system (GNSS) device when the result of the deception detection is that a deception attack has occurred.

[0072] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0074] Figure 1 This is a flowchart of a method for defending against satellite navigation timing deception and interference according to an embodiment of the present application;

[0075] Figure 2 1. A flowchart of direct time output timing deception interference defense according to one embodiment of the present application;

[0076] Figure 3 A flowchart of local clock taming and timing deception interference defense according to one embodiment of the present application is shown;

[0077] Figure 4 This is a schematic diagram of a test scenario according to an embodiment of the present application;

[0078] Figure 5 Schematic diagram comparing the timing errors of the present application and conventional methods before spoofing is detected under a spoofing attack according to one embodiment of the present application;

[0079] Figure 6 2. A schematic diagram comparing the local clock bias solution results of the present application and the conventional method under normal conditions according to an embodiment of the present application;

[0080] Figure 7 2. A schematic diagram comparing the local clock drift solution results of the present application and the conventional method under normal conditions according to an embodiment of the present application;

[0081] Figure 8 This is an example diagram of a satellite navigation timing deception and interference prevention device according to an embodiment of the present application;

[0082] Figure 9Schematic diagram of a block diagram of an electronic device according to an embodiment of the present application. DETAILED DESCRIPTION

[0083] The following describes in detail embodiments of the present application, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0084] The following describes the satellite navigation timing deception interference defense method, device, electronic device and medium of the embodiment of the present application with reference to the accompanying drawings. In view of the problem that the GNSS deception detection technology in the related technology mentioned in the background technology center requires collecting GNSS data for a long time to obtain a more reliable detection result, resulting in the timing result deviation exceeding the user's acceptable range before the deception signal is detected, the present application provides a satellite navigation timing deception interference defense method, in which multiple observation quantities of the satellite and the cumulative length of the multiple observation quantities are obtained according to the satellite signal, and new information is estimated according to the current satellite on-orbit motion state, multiple propagation delay correction parameters, pseudorange observation quantities and pseudorange rate observation quantities, and the new information constraint parameters are calculated. When the cumulative length meets the preset deception detection condition, deception detection is performed, and when the result of the deception detection is that a deception attack exists, a deception warning is initiated to the user of the global navigation satellite system GNSS device. This solves the problem that the GNSS spoofing detection technology in the related art needs to collect GNSS data for a long time to obtain more reliable detection results, resulting in the timing result deviation exceeding the user's acceptable range before the spoofing signal is detected. It ensures the user's GNSS timing accuracy and helps to defend against various timing spoofing attacks, especially the gradual timing spoofing attacks that are highly concealed and harmful, so as to achieve the purpose of improving the security of GNSS timing.

[0085] Specifically, Figure 1 This is a flowchart of a method for defending against satellite navigation timing deception and interference provided in an embodiment of the present application.

[0086] like Figure 1 As shown, the satellite navigation timing deception interference defense method includes the following steps:

[0087] In step S101, a satellite signal from at least one satellite is received, and a plurality of observation quantities and cumulative lengths of the plurality of observation quantities of the at least one satellite are obtained based on the satellite signal, wherein the plurality of observation quantities include a pseudorange observation quantity, a pseudorange rate observation quantity, an on-orbit motion state of the satellite at a current moment from the satellite ephemeris, and a plurality of propagation delay correction parameters at a current moment from the satellite ephemeris.

[0088] Specifically, the embodiment of the present application obtains a priori rough estimates of the local clock state vector b and its covariance matrix Q according to conventional methods, sets the maximum allowable timing error, i.e., the timing safety margin B0, and sets various initial parameters of the local clock filter: the accumulated clock drift change b a = 0, cumulative clock deviation change b a = 0, the maximum clock bias change during each iterative calculation is B = B0 / L, the iteration counter n = 1, the covariance matrix M = Q, and the cumulative innovation constraint r = 0. The received K (if the user position is fixed and known, K ≥ 1 is required; otherwise, K ≥ 4 is required) satellite signals are subjected to conventional front-end filtering, down-conversion, sampling, quantization, and other processing to obtain a digital intermediate frequency signal. The obtained digital intermediate frequency signal is then subjected to conventional signal processing such as acquisition, tracking, and demodulation to obtain multiple observations of multiple satellites and the cumulative length of the multiple observations, and the pseudorange observation ρ is extracted. i (i=1,2,...,K), pseudo-range rate observation Satellite ephemeris and other information.

[0089] In step S102, innovation estimation is performed based on the current satellite on-orbit motion state, multiple propagation delay correction parameters, pseudorange observations, and pseudorange rate observations, and innovation constraint parameters are calculated.

[0090] Optionally, in some embodiments, the estimation and calculation strategy for performing innovation estimation and calculating innovation constraint parameters based on the current satellite on-orbit motion state, multiple propagation delay correction parameters, pseudorange observations, and pseudorange rate observations is as follows:

[0091]

[0092]

[0093]

[0094]

[0095] M′←AMA T +Q

[0096] K←M′H(C+HM′H T ) -1 ; (1)

[0097] M←(I-KH)M′

[0098]

[0099]

[0100]

[0101] in, is the corrected pseudorange observation of the i-th signal, ρ i is the pseudorange observation, is the corrected pseudorange rate observation of the i-th signal, P u is the position vector, P i is the satellite position vector, c is the speed of light, I i is the total correction for tropospheric and ionospheric delay, b i is the satellite clock bias, is the pseudo-range rate observation, V u is the velocity vector, V i is the velocity vector, is the spatial distance correction observation vector, is the prior estimate of the observation vector at the current moment based on the local clock state at the previous moment, M′ is the prior estimate covariance matrix, M is the posterior estimate covariance matrix, Q is the covariance matrix, β is the intermediate term for calculating the innovation constraint coefficient, β is the intermediate term for calculating the innovation constraint coefficient, α is the innovation constraint parameter, ||·|| represents the modulus of the calculated vector, exp is the natural exponential function, min is the minimum function, and T is the vector or matrix transpose.

[0102] It can be understood that the embodiment of the present application constructs a joint observation quantity vector and a covariance matrix based on the pseudorange observation quantity and the pseudorange rate observation quantity, and based on a preset correction strategy, corrects the joint observation quantity vector through multiple correction parameters to obtain a spatial distance corrected observation quantity vector, and updates the local clock state vector and clock filter parameters according to the spatial distance corrected observation quantity vector and the covariance matrix, and obtains the innovation constraint parameters based on the estimation and calculation strategy of the innovation constraint parameters.

[0103] In step S103, it is determined whether the cumulative length meets the preset deception detection condition, and a deception detection is performed when the cumulative length meets the preset deception detection condition. When the result of the deception detection is that a deception attack exists, a deception alarm is issued to the user of the global navigation satellite system GNSS device.

[0104] It is understood that if the accumulated observations reach the cumulative length L of observations required by the applied spoofing detection algorithm, spoofing detection is performed when it is determined that the accumulated observations meet the preset spoofing detection conditions. If the detection result indicates the presence of a spoofing attack, the user-preset spoofing attack processing function is activated. For example, the application of local clock devices such as GNSS time training crystal oscillators and atomic clocks can be stopped and put into self-timekeeping mode, spoofing warnings can be issued to users of GNSS devices, and spoofing interference sources can be identified and eliminated.

[0105] Optionally, in some embodiments, after determining whether the cumulative length satisfies a preset spoofing detection condition, the method further includes: if the cumulative length does not satisfy the preset spoofing detection condition, updating the local clock state vector and various filter state parameters based on a preset first update strategy; wherein the preset first update strategy is:

[0106] b←b+αKγ

[0107] r←(I-KH)Ar+(1-α)Kγ

[0108]

[0109]

[0110]

[0111] n←n+1; (2)

[0112] Among them, ← is the assignment operator, e1=[1,0], b is the local clock state vector, B0 is the timing safety margin, L is the measurement length, and n is the iteration counter.

[0113] It is understandable that when the accumulated observation length does not meet the accumulated length L required by the selected deception detection algorithm, the local clock state vector and clock filter parameters are updated according to the preset first update strategy, including the accumulated clock drift change. Cumulative clock deviation change b a , maximum clock bias change B and iteration counter n.

[0114] Optionally, in some embodiments, after determining that the cumulative length meets a preset spoofing detection condition and performing spoofing detection, the method further includes: if the spoofing result is that there is no spoofing attack, updating the local clock state vector based on a preset second update strategy, and initializing the clock filter parameters according to a preset initialization strategy; wherein the preset second update strategy is:

[0115] b←b+Kγ+(I-KH)Ar;(3)

[0116] The default initialization strategy is:

[0117] r←0

[0118]

[0119] b a ←0. (4)

[0120] B←B0 / (LΔt)

[0121] n←1

[0122] It should be understood that if the spoofing result shows that there is no spoofing attack, the local clock state vector and the clock filter parameters are updated based on the preset second update strategy.

[0123] Furthermore, in some embodiments, the above-mentioned satellite navigation timing spoofing and interference defense method also includes: after updating the local clock state parameters, obtaining the user's timing usage mode of GNSS; if the timing usage mode is to directly use the time provided by GNSS, then according to the updated local clock state vector b and the updated clock filter parameters (including at least one of the accumulated clock drift change, the accumulated clock bias change, the maximum clock bias change and the accumulated new information constraint), the current time is calculated, and the current time is directly output for the user to use; if the timing usage mode is the local clock taming mode, then according to the updated local clock state vector b and the updated clock filter parameters (including at least one of the accumulated clock drift change, the accumulated clock bias change, the maximum clock bias change and the accumulated new information constraint), the local clock correction parameters are calculated, and the local clock is tamed based on the local clock correction parameters, and the time output by the tamed local clock is provided for the user to use.

[0124] Specifically, the user's use of GNSS timing is obtained. For users who directly use the time provided by GNSS, such as Figure 2 As shown, based on the updated local clock state vector and the updated clock filter parameters, including at least one of the accumulated clock drift change, the accumulated clock bias change, the maximum clock bias change, and the accumulated innovation constraint, the current time is calculated according to the conventional method, and the time result is directly output for the user to use. If the timing usage mode is the local clock training mode, then for users who use the time information provided by GNSS to train self-timekeeping devices such as crystal oscillators and atomic clocks, as shown in the figure, Figure 3 As shown, the updated local clock state vector and the updated clock filter parameters are used to calculate the local clock correction parameters, the local clock correction parameters are calculated according to the conventional method, the local clock is tamed using the local clock correction parameters, and the tamed local clock is used to output the time result for the user.

[0125] Furthermore, the system returns to continue receiving and processing GNSS signals and executes subsequent steps to obtain the pseudorange, pseudorange rate, and observation quantities required for spoofing detection at the next moment, thereby iterating the next timing and anti-spoofing calculations.

[0126] To verify the validity of this application, the embodiment of this application carried out an experiment based on a commercial constant temperature crystal oscillator by receiving the Beidou civil B1I signal. The experimental scene is set as follows: Figure 4 shown.

[0127] The total recording time of the experimental data is 3600s, the update time interval of the pseudorange and pseudorange rate observations is 1s, and 6 Beidou satellite signals are used, that is, K = 6.

[0128] First, in order to intuitively demonstrate the application effect of the present invention in preventing the problem of fraudulent influence exceeding the security threshold compared with traditional methods, Figure 5 The comparison of the timing results of the method proposed in the present invention and the conventional method when different security thresholds are set under two different detection cycles is shown. The experiment sets the deception to start after the 150th second, and the deception is detected at the 165th second by applying the detection with a shorter period of 15 seconds (which requires a higher computing power of the device), and the deception is detected at the 200th second by applying the detection with a longer period of 50 seconds (which requires a lower computing power of the device). After the deception is detected, its impact can be suppressed in the first time. However, before the deception signal is detected, the conventional timing method, whether it is the timing result obtained by a single point or the timing result obtained based on the filtering method, is significantly tampered with. In comparison, the embodiment of the present application can constrain the impact of the deception attack on the timing result to below the set safety tolerance B0 before the deception is detected, thereby achieving the purpose of protecting the user's time security.

[0129] In addition, in order to verify that under normal conditions, that is, when there is no spoofing attack, the embodiment of the present application will not have a significant impact on the user's timing accuracy, and can meet the high-precision time requirements of various current GNSS timing users, Figure 6 and Figure 7 The figures show the local clock bias and drift calculated by the embodiments of the present application and conventional timing methods, when no spoofing attacks are present. The figures show that compared to conventional filtering timing methods, the method proposed in the present application has essentially the same timing accuracy and stability; compared to conventional single-point timing methods, the method proposed in the embodiments of the present application has higher timing accuracy and stability.

[0130] The above two sets of experimental results verify the effect of the embodiment of the present application: the embodiment of the present application can effectively suppress the maximum impact of the spoofing attack before it is detected while ensuring the user's GNSS timing accuracy, ensure that the timing deviation caused by the spoofing does not exceed the safety threshold set by the user, and significantly improve the GNSS user timing security.

[0131] In order to enable those skilled in the art to further understand the satellite navigation timing deception and interference defense method of the embodiment of the present application, it is described in detail below with reference to specific embodiments.

[0132] The present embodiment uses the BeiDou civilian B1I signal as an example to implement the steps. The implementation of the method is not limited to a specific navigation system, signal, or specific parameters and can be flexibly selected. The signal environment and parameters tested are as follows: The GNSS device simultaneously receives and processes six BeiDou satellite signals. The user's position is fixed and known. The device uses a direct time output timing mode, which directly outputs the time information obtained from the BeiDou signal for the user to use.

[0133] The specific steps for implementation are as follows:

[0134] In step 1, the safety margin of the timing error is set to 100 nanoseconds (ns), the cumulative length of the observation required for deception detection is set to 50 seconds (s), and the clock state parameters and filter parameters are initialized;

[0135] In step 2, the received 6 satellite signals are down-converted, sampled, quantized, and processed according to conventional methods to obtain digital intermediate frequency signals;

[0136] In step 3, the digital intermediate frequency signal obtained in step 1 is captured, tracked, and demodulated according to conventional methods to extract the Beidou system's ephemeris and calculate the real-time satellite position, velocity, and other corrections. At the same time, the pseudorange and pseudorange rate observations of the six satellite signals tracked by the receiver are extracted, and the correction observation vector is calculated according to the various information demodulated according to the preset correction strategy.

[0137] In step 4, we start based on the observation vector The preset third update strategy, the hard upper limit of the innovation constraint parameter, and the preset accumulation function are sequentially used to calculate the constraint parameters for the observation innovation and update some filter parameters. Signal power, Doppler shift, signal quality monitoring, and clock drift sequence observations are simultaneously accumulated as observations for spoofing detection. If the 50 seconds of observation accumulation required for spoofing detection have not been completed, proceed to step 5. When the 50 seconds of observation accumulation required for spoofing detection have been completed, spoofing detection is performed according to the requirements of the spoofing detection algorithm. If the detection result indicates the absence of a spoofing signal, proceed to step 6. If the detection result indicates the presence of a spoofing signal, proceed to step 7.

[0138] In step 5, the clock state parameters are updated using the constrained observation information using the preset second update strategy. Results show that the user's local clock drifts at a rate of 0.25017 to 1.7684 nanoseconds per second. The current time is calculated based on the clock state using the direct time output timing method and output for user use. The system then returns to step 2 to receive and process the next BeiDou signal.

[0139] In step 6, a spoofing check is performed every 50 seconds. No spoofing is detected at the 50th, 100th, and 150th seconds. Therefore, the clock state vector is updated according to the preset first update strategy at these moments. Then, some filter parameters are initialized according to the preset initialization strategy. After the calculation is completed, the process returns to step 2 to receive and process the next Beidou signal.

[0140] In step 7, a spoofing attack is detected at the 200th second. According to the user's preset spoofing attack processing procedure, a spoofing alert is issued to the user, the use of GNSS time information is stopped, and the source of spoofing interference is checked.

[0141] According to the satellite navigation timing deception interference defense method proposed in the embodiment of the present application, multiple observation quantities of the satellite and the cumulative length of multiple observation quantities are obtained based on the satellite signal, and new information is estimated based on the current satellite on-orbit motion state, multiple propagation delay correction parameters, pseudorange observation quantities and pseudorange rate observation quantities, and the new information constraint parameters are calculated. When the cumulative length meets the preset deception detection conditions, deception detection is performed, and when the result of the deception detection is that there is a deception attack, a deception alarm is initiated to the user of the global navigation satellite system GNSS device. In this way, the problem that the GNSS deception detection technology in the related art needs to collect GNSS data for a long time to obtain a more reliable detection result is solved, resulting in the deviation of the timing result exceeding the user's acceptable range before the deception signal is detected, and the user's GNSS timing accuracy is guaranteed, which helps to defend against various timing deception attacks, especially the gradual timing deception attacks that are highly concealed and harmful, and achieve the purpose of improving the security of GNSS timing.

[0142] Next, the satellite navigation timing deception and interference prevention device proposed in accordance with an embodiment of the present application will be described with reference to the accompanying drawings.

[0143] Figure 8 It is a block diagram of a satellite navigation timing deception and interference defense device according to an embodiment of the present application.

[0144] like Figure 8 As shown, the satellite navigation timing deception interference defense device 10 includes: an acquisition module 100, a calculation module 200 and a judgment module 300.

[0145] Among them, the acquisition module 100 is used to receive satellite signals from at least one satellite, and obtain multiple observation quantities and cumulative lengths of multiple observation quantities of at least one satellite based on the satellite signals, wherein the multiple observation quantities include pseudorange observation quantities, pseudorange rate observation quantities, the satellite's on-orbit motion state at the current moment from the satellite ephemeris, and multiple propagation delay correction parameters at the current moment from the satellite ephemeris; the calculation module 200 is used to estimate new information based on the satellite's on-orbit motion state at the current moment, multiple propagation delay correction parameters at the current moment, the pseudorange observation quantities and the pseudorange rate observation quantities, and calculate new information constraint parameters; the judgment module 300 is used to judge whether the cumulative length meets the preset deception detection conditions, and perform deception detection when the cumulative length meets the preset deception detection conditions, and initiate a deception alarm to the user of the global navigation satellite system GNSS device when the result of the deception detection is that a deception attack exists.

[0146] Optionally, in some embodiments, after determining that the cumulative length does not meet a preset fraud detection condition, the determination module 300 is further configured to: update the local clock state vector and various filter state parameters based on a preset first update strategy;

[0147] Among them, the preset first update strategy is:

[0148] b←b+αKγ

[0149] r←(I-KH)Ar+(1-α)Kγ

[0150]

[0151]

[0152]

[0153] n←n+1

[0154] Among them, ← is the assignment operator, b is the local clock state vector, K is the gain matrix, γ is the observation innovation, r is the cumulative amount of innovation constraint, I is the 2K-order unit matrix, Δt is the time interval between two observations, (1 and 0 are all-1 and all-0 column vectors of length K respectively), c is the speed of light, is the cumulative clock drift change, b a is the cumulative clock bias change, B is the maximum clock bias change, e1 = [1, 0], e2 = [0, 1], B0 is the timing safety margin, L is the measurement length, n is the iteration counter, and |·| is the absolute value of the calculated scalar.

[0155] Optionally, in some embodiments, after performing the spoofing detection, the judgment module 300 is further configured to: if the spoofing result is that there is no spoofing attack, update the local clock state vector based on a preset second update strategy, and initialize the clock filter parameters according to a preset initialization strategy;

[0156] Among them, the preset second update strategy is:

[0157] b←b+Kγ+(I-KH)Ar;

[0158] The default initialization strategy is:

[0159] r←0

[0160]

[0161] b a ←0.

[0162] B←B0 / (LΔt)

[0163] n←1

[0164] Optionally, in some embodiments, the calculation module 200 is further configured to: perform innovation estimation and calculate innovation constraint parameters based on the current satellite on-orbit motion state, multiple propagation delay correction parameters, pseudorange observations, and pseudorange rate observations. The estimation and calculation strategy is as follows:

[0165]

[0166]

[0167]

[0168]

[0169] M′←AMA T +Q

[0170] K←M′H(C+HM′H T ) -1 ;

[0171] M←(I-KH)M′

[0172]

[0173]

[0174]

[0175] in, is the corrected pseudorange observation of the i-th signal, ρ iis the pseudorange observation, is the corrected pseudorange rate observation of the i-th signal, P u is the position vector, P i is the satellite position vector, c is the speed of light, I i is the total correction for tropospheric and ionospheric delay, b i is the satellite clock bias, is the pseudo-range rate observation, V u is the velocity vector, V i is the velocity vector, is the spatial distance correction observation vector, is the prior estimate of the observation vector at the current moment based on the local clock state at the previous moment, M′ is the prior estimate covariance matrix, M is the posterior estimate covariance matrix, Q is the covariance matrix, β is the intermediate term for calculating the innovation constraint coefficient, β is the intermediate term for calculating the innovation constraint coefficient, α is the innovation constraint parameter, ||·|| represents the modulus of the calculated vector, exp is the natural exponential function, min is the minimum function, and T is the vector or matrix transpose.

[0176] Optionally, in some embodiments, the judgment module 300 is further used to: obtain the user's timing usage mode of GNSS after updating the local clock state parameters; if the timing usage mode is to directly use the time provided by GNSS, then calculate the current time according to the updated local clock state vector b and the updated clock filter parameters (including at least one of the accumulated clock drift change, the accumulated clock bias change, the maximum clock bias change and the accumulated new information constraint), and directly output the current time for the user to use; if the timing usage mode is the local clock taming mode, then calculate the local clock correction parameters according to the updated local clock state vector b and the updated clock filter parameters (including at least one of the accumulated clock drift change, the accumulated clock bias change, the maximum clock bias change and the accumulated new information constraint), tame the local clock based on the local clock correction parameters, and provide the time output by the tamed local clock for the user to use.

[0177] It should be noted that the above explanation of the embodiment of the satellite navigation timing deception and interference defense method is also applicable to the satellite navigation timing deception and interference defense device of this embodiment, and will not be repeated here.

[0178] According to the satellite navigation timing deception interference defense device proposed in the embodiment of the present application, multiple observation quantities of the satellite and the cumulative length of multiple observation quantities are obtained based on the satellite signal, and new information is estimated based on the current satellite on-orbit motion state, multiple propagation delay correction parameters, pseudorange observation quantities and pseudorange rate observation quantities, and the new information constraint parameters are calculated. When the cumulative length meets the preset deception detection conditions, deception detection is performed, and when the result of the deception detection is that there is a deception attack, a deception alarm is initiated to the user of the global navigation satellite system GNSS device. In this way, the problem that the GNSS deception detection technology in the related art needs to collect GNSS data for a long time to obtain a more reliable detection result is solved, resulting in the deviation of the timing result exceeding the user's acceptable range before the deception signal is detected, and the user's GNSS timing accuracy is guaranteed, which helps to defend against various timing deception attacks, especially the gradual timing deception attacks that are highly concealed and harmful, and achieve the purpose of improving the security of GNSS timing.

[0179] Figure 9 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. The electronic device may include:

[0180] A memory 901 , a processor 902 , and a computer program stored in the memory 901 and executable on the processor 902 .

[0181] When the processor 902 executes the program, the satellite navigation timing deception interference defense method provided in the above embodiment is implemented.

[0182] Furthermore, the electronic device further includes:

[0183] The communication interface 903 is used for communication between the memory 901 and the processor 902 .

[0184] The memory 901 is used to store computer programs that can be run on the processor 902 .

[0185] The memory 901 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0186] If the memory 901, processor 902, and communication interface 903 are implemented independently, the communication interface 903, memory 901, and processor 902 can be connected to each other via a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 9 Only one thick line is used in the diagram, but this does not mean that there is only one bus or one type of bus.

[0187] Optionally, in a specific implementation, if the memory 901, the processor 902 and the communication interface 903 are integrated on a chip, the memory 901, the processor 902 and the communication interface 903 can communicate with each other through an internal interface.

[0188] The processor 902 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0189] An embodiment of the present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-mentioned satellite navigation timing deception and interference defense method.

[0190] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0191] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Thus, a feature specified as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this application, "N" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0192] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may be performed out of the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present application belong.

[0193] The logic and / or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing the logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (e.g., a computer-based system, a system including a processor, or other system that can fetch and execute instructions from an instruction execution system, apparatus, or device). For purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include the following: an electrical connection with one or N wires (electronic devices), a portable computer disk cartridge (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and programmable read-only memory (EPROM or flash memory), fiber optic devices, and a portable compact disc read-only memory (CDROM). Furthermore, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing it in another suitable manner if necessary, and then storing it in a computer memory.

[0194] It should be understood that various parts of the present application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiment, the N steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof can be used to implement: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application-specific integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0195] Those skilled in the art will understand that all or part of the steps in the method of the above embodiment can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiment.

[0196] In addition, the functional units in the various embodiments of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into a module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0197] The storage medium mentioned above may be a read-only memory, a magnetic disk, or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present application. Persons skilled in the art may make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. A method for defending against satellite navigation timing deception and interference, characterized in that: The following steps are involved: receiving a satellite signal from at least one satellite, and obtaining a plurality of observation quantities of the at least one satellite and a cumulative length of the plurality of observation quantities based on the satellite signal, wherein the plurality of observation quantities include a pseudorange observation quantity, a pseudorange rate observation quantity, an on-orbit motion state of the satellite at a current moment from the satellite ephemeris, and a plurality of propagation delay correction parameters at a current moment from the satellite ephemeris; performing innovation estimation based on the satellite's on-orbit motion state at the current moment, the plurality of propagation delay correction parameters at the current moment, the pseudorange observations, and the pseudorange rate observations, and calculating innovation constraint parameters; determining whether the cumulative length satisfies a preset spoofing detection condition, performing spoofing detection when the cumulative length satisfies the preset spoofing detection condition, and initiating a spoofing alert to a user of a Global Navigation Satellite System (GNSS) device if a spoofing attack is detected; Innovation estimation is performed based on the satellite's on-orbit motion state at the current moment, the multiple propagation delay correction parameters at the current moment, the pseudorange observations, and the pseudorange rate observations. The calculation strategy for estimating innovation constraint parameters is: ； in, is the assignment operator, For the The corrected pseudo-range observation of the road signal, is the pseudorange observation, For the The corrected pseudo-range rate observation of the road signal, is the position vector, is the satellite position vector, is the speed of light, is the total correction for tropospheric and ionospheric delay, is the satellite clock bias, is the pseudorange rate observation, is the velocity vector, is the velocity vector, is the spatial distance correction observation vector, is the prior estimate of the observation vector at the current moment based on the local clock state at the previous moment, is the prior estimated covariance matrix, is the posterior estimated covariance matrix, is the covariance matrix, is the intermediate term for calculating the innovation constraint coefficient, is the innovation constraint parameter, Indicates the calculation of vector modulus, To calculate the absolute value of a scalar, is the natural exponential function, To obtain the minimum function, is the vector or matrix transpose, is the gain matrix, , ,in, and The lengths are A column vector of all 1s and all 0s, is the maximum clock deviation change, , is the observation quantity innovation, is the cumulative clock deviation change, is the cumulative clock drift change, is the local clock state vector, for The identity matrix of order.

2. The method according to claim 1, characterized in that After determining that the cumulative length does not meet the preset fraud detection condition, the method further includes: Update the local clock state vector and various filter state parameters based on a preset first update strategy; The preset first update strategy is: ； in, is the assignment operator, is the local clock state vector, is the gain matrix, is the observation quantity innovation, is the cumulative amount of innovation constraint, is the time interval between two observations, , is the speed of light, is the cumulative clock drift change, is the cumulative clock deviation change, is the maximum clock deviation change, , is the timing safety margin, To measure length, Iteration counter.

3. The method according to claim 2, characterized in that After determining that the cumulative length meets a preset fraud detection condition and performing fraud detection, the method further includes: If the spoofing result is that there is no spoofing attack, then updating the local clock state vector based on the preset second update strategy, and then initializing the clock filter parameters according to the preset initialization strategy; The preset second update strategy is: ； The preset initialization strategy is: 。 4. The method according to claim 2 or 3, characterized in that Also includes: After updating the local clock state parameters, obtaining the user's timing usage mode of the GNSS; If the timing mode is to directly use the time provided by the GNSS, then according to the updated local clock state vector calculating the current time using the updated clock filter parameters and directly outputting the current time for use by the user, wherein the clock filter parameters include at least one of a cumulative clock drift change, a cumulative clock bias change, a maximum clock bias change, and a cumulative innovation constraint; If the timing mode is the local clock training mode, then according to the updated local clock state vector The local clock correction parameters are calculated based on the updated clock filter parameters, the local clock is tamed based on the local clock correction parameters, and the time output by the tamed local clock is provided to the user.

5. A satellite navigation timing deception interference defense device, characterized in that: include: an acquisition module, configured to receive a satellite signal from at least one satellite, and obtain, based on the satellite signal, a plurality of observation quantities of the at least one satellite and a cumulative length of the plurality of observation quantities, wherein the plurality of observation quantities include a pseudorange observation quantity, a pseudorange rate observation quantity, an on-orbit motion state of the satellite at a current moment from the satellite ephemeris, and a plurality of propagation delay correction parameters at a current moment from the satellite ephemeris; a calculation module, configured to perform innovation estimation based on the satellite's on-orbit motion state at the current moment, the multiple propagation delay correction parameters at the current moment, the pseudorange observations, and the pseudorange rate observations, and calculate innovation constraint parameters; a determination module, configured to determine whether the cumulative length satisfies a preset spoofing detection condition, perform spoofing detection when the cumulative length satisfies the preset spoofing detection condition, and initiate a spoofing alert to a user of a Global Navigation Satellite System (GNSS) device if a spoofing attack is detected by the spoofing detection; In the calculation module, the innovation estimation is performed based on the current satellite on-orbit motion state, the multiple propagation delay correction parameters at the current moment, the pseudorange observations, and the pseudorange rate observations. The calculation strategy for estimating the innovation constraint parameters is: ； in, is the assignment operator, For the The corrected pseudo-range observation of the road signal, is the pseudorange observation, For the The corrected pseudo-range rate observation of the road signal, is the position vector, is the satellite position vector, is the speed of light, is the total correction for tropospheric and ionospheric delay, is the satellite clock bias, is the pseudorange rate observation, is the velocity vector, is the velocity vector, is the spatial distance correction observation vector, is the prior estimate of the observation vector at the current moment based on the local clock state at the previous moment, is the prior estimated covariance matrix, is the posterior estimated covariance matrix, is the covariance matrix, is the intermediate term for calculating the innovation constraint coefficient, is the innovation constraint parameter, Indicates the calculation of vector modulus, To calculate the absolute value of a scalar, is the natural exponential function, To obtain the minimum function, is the vector or matrix transpose, is the gain matrix, , ,in, and The lengths are A column vector of all 1s and all 0s, is the maximum clock deviation change, , is the observation quantity innovation, is the cumulative clock deviation change, is the cumulative clock drift change, is the local clock state vector, for The identity matrix of order.

6. The device according to claim 5, characterized in that After determining that the cumulative length does not meet the preset fraud detection condition, the judgment module is further configured to: Update the local clock state vector and various filter state parameters based on a preset first update strategy; The preset first update strategy is: ； in, is the assignment operator, is the local clock state vector, is the gain matrix, is the observation quantity innovation, is the cumulative amount of innovation constraint, is the time interval between two observations, , is the speed of light, is the cumulative clock drift change, is the cumulative clock deviation change, is the maximum clock deviation change, , is the timing safety margin, To measure length, Iteration counter.

7. The device according to claim 6, characterized in that After determining that the cumulative length meets a preset fraud detection condition and performing fraud detection, the judgment module is further configured to: If the spoofing result is that there is no spoofing attack, the local clock state vector is updated based on the preset second update strategy, and then the clock filter parameters are initialized according to the preset initialization strategy; The preset second update strategy is: ； The preset initialization strategy is: 。 8. The device according to claim 6 or 7, characterized in that Also used for: After updating the local clock state parameters, obtaining the user's timing usage mode of the GNSS; If the timing mode is to directly use the time provided by the GNSS, then according to the updated local clock state vector calculating the current time using the updated clock filter parameters and directly outputting the current time for use by the user, wherein the clock filter parameters include at least one of a cumulative clock drift change, a cumulative clock bias change, a maximum clock bias change, and a cumulative innovation constraint; If the timing mode is the local clock training mode, then according to the updated local clock state vector The local clock correction parameters are calculated based on the updated clock filter parameters, the local clock is tamed based on the local clock correction parameters, and the time output by the tamed local clock is provided to the user.

9. An electronic device, characterized in that: Including memory and processor; The processor runs a program corresponding to the executable program code by reading the executable program code stored in the memory, so as to implement the satellite navigation timing deception interference defense method as described in any one of claims 1-4.

10. A computer-readable storage medium storing a computer program, characterized in that: When the program is executed by a processor, the satellite navigation timing deception interference defense method as described in any one of claims 1 to 4 is implemented.

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