Deception signal detection method, device, electronic device and storage medium

Abstract

The present invention relates to a spoofing signal detection method, device, electronic device and storage medium, and belongs to the technical field of satellite navigation systems. The present invention detects spoofing signals based on correlation peaks according to the characteristic that when a spoofing signal exists, the ratio value difference between the first peak and the second peak of a GNSS signal is small, and can quickly and timely detect whether there is a spoofing signal in the GNSS signal. The implementation is simple and convenient for real-time processing by a GNSS chip.

Description

Background Art

[0002] For the Global Navigation Satellite System (GNSS), there may be spoofing signals in the signals received by its receiver. The spoofing signals can be divided into forwarding spoofing signals and generating spoofing signals. They are intended to forward or forge erroneous navigation information to mislead the receiver, thereby destroying or even controlling the receiver's positioning results.

[0003] Existing spoofing signal detection technologies, such as the spoofing signal detection method based on channel difference, need to statistically analyze channel characteristics and establish a forwarding spoofing interference channel model to distinguish it from the interference-free real signal model. The implementation is relatively complex and the model is difficult to accurately distinguish. The spoofing signal detection method based on capture and search needs to re-divide the sampling data through the preliminary capture results, repeat the capture search multiple times, and transfer the capture results of multiple satellites to tracking. Finally, the real signal is judged according to the calculated signal transmission time. This method can only detect forwarding spoofing interference and is ineffective for generating spoofing interference. The implementation is relatively complex and requires repeated division and capture of a section of stored intermediate frequency sampling data, and multiple tracking channels are required for simultaneous tracking. A large amount of hardware resources are consumed for capture and tracking, which is not conducive to the real-time processing of GNSS chips.

[0004] Based on the above analysis, the existing spoofing signal detection technology has the disadvantages of being complex to implement and not conducive to the real-time processing of GNSS chips. Summary of the invention

[0005] In order to solve the defects of the existing spoofing signal detection technology, which is complex to implement and not conducive to the real-time processing of GNSS chips, the present invention provides a spoofing signal detection method, device, electronic device and storage medium.

[0006] In a first aspect, in order to solve the above technical problem, the present invention provides a spoof signal detection method, comprising:

[0007] Acquire GNSS signals;

[0008] Perform frequency conversion on the GNSS signal to obtain intermediate frequency sampling data;

[0009] Capture and process the intermediate frequency sampling data to obtain multiple correlation peaks;

[0010] Based on the peak value of the first peak, the peak value of the second peak, and the average value of the peak values ​​of the multiple correlation peaks, a ratio value corresponding to the first peak and a ratio value corresponding to the second peak are calculated, wherein the first peak is a correlation peak with the largest peak value among the multiple correlation peaks, and the second peak is a correlation peak with the largest peak value among the multiple correlation peaks except the first peak;

[0011] If the difference between the ratio value corresponding to the first peak and the ratio value corresponding to the second peak is smaller than the first ratio value threshold, it is determined that there is a spoofing signal in the GNSS signal.

[0012] The beneficial effects of the present invention are as follows: according to the characteristic that when a spoofing signal exists, the ratio difference between the first peak and the second peak of the GNSS signal is small, spoofing signal detection is performed based on correlation peaks, so that whether there is a spoofing signal in the GNSS signal can be quickly and timely detected. The implementation is simple and convenient for real-time processing by a GNSS chip.

[0013] Furthermore, the intermediate frequency sampling data is captured and processed to obtain multiple correlation peaks, including:

[0014] Based on the set multiple Doppler frequencies and the set multiple code phases, a plurality of local carriers are generated, wherein different local carriers have different Doppler frequencies or different code phases;

[0015] For each local carrier, correlation processing is performed on the local carrier and the intermediate frequency sampling data to obtain a correlation peak corresponding to the local carrier.

[0016] The beneficial effect of adopting the above-mentioned improved solution is that the correlation peak is obtained based on the two-dimensional search of the code frequency, and the implementation is simple.

[0017] Further, the spoofing signal includes at least one of a forwarding spoofing signal and a generated spoofing signal, and if the difference between the ratio value corresponding to the first peak and the ratio value corresponding to the second peak is less than a first ratio value threshold, determining that there is a spoofing signal in the GNSS signal includes:

[0018] If the difference between the ratio value corresponding to the first peak and the ratio value corresponding to the second peak is less than the first ratio value threshold, the first peak is compared with the second peak to obtain a first comparison result;

[0019] If the first comparison result meets the first set condition, it is determined that there is a forwarding spoofing signal in the GNSS signal; if the first comparison result meets the second set condition, it is determined that there is a generated spoofing signal in the GNSS signal;

[0020] The first setting condition is that the Doppler frequency corresponding to the first peak is equal to the Doppler frequency corresponding to the second peak, and the difference between the code phase corresponding to the first peak and the code phase corresponding to the second peak is less than the first code phase threshold;

[0021] The second setting condition is that the difference between the Doppler frequency corresponding to the first peak and the Doppler frequency corresponding to the second peak is greater than the first Doppler frequency threshold, and the difference between the code phase corresponding to the first peak and the code phase corresponding to the second peak is greater than the second code phase threshold.

[0022] The beneficial effect of adopting the above-mentioned improvement scheme is: according to the difference in the ratio value of the first peak and the second peak, the difference in Doppler frequency and the difference in code phase, fast and effective detection of forwarding spoofing signals and generated spoofing signals can be achieved.

[0023] Furthermore, if the difference between the ratio value corresponding to the first peak and the ratio value corresponding to the second peak is less than the first ratio value threshold, before determining that there is a spoofing signal in the GNSS signal, the method further includes:

[0024] Determine a correlation peak with the largest peak value among the correlation peaks that meet a third setting condition among the multiple correlation peaks as a third peak value, wherein the third setting condition is that the peak value of the correlation peak is smaller than the peak value of the second peak value;

[0025] Based on the peak value average of the multiple correlation peaks and the peak value of the third peak, a proportion value corresponding to the third peak is calculated;

[0026] Compare the first peak and the third peak to obtain a second comparison result;

[0027] If the second comparison result does not meet the fourth setting condition, reacquiring the GNSS signal;

[0028] Among them, the fourth setting condition is that the difference between the Doppler frequency corresponding to the first peak and the Doppler frequency corresponding to the third peak is less than the second Doppler frequency threshold, the difference between the code phase corresponding to the first peak and the code phase corresponding to the third peak is less than the third code phase threshold, the difference between the proportion value corresponding to the first peak and the proportion value corresponding to the third peak is greater than the second proportion value threshold, and the proportion value corresponding to the first peak is greater than the third proportion value threshold.

[0029] The beneficial effect of adopting the above-mentioned improvement scheme is: based on the first peak and the third peak, the validity of the intermediate frequency sampling data used for spoofing signal detection is judged, thereby avoiding erroneous detection caused by invalid intermediate frequency sampling data.

[0030] Further, if the difference between the ratio value corresponding to the first peak and the ratio value corresponding to the second peak is less than the first ratio value threshold, it is determined that there is a spoofing signal in the GNSS signal, including:

[0031] If the difference between the ratio value corresponding to the first peak and the ratio value corresponding to the second peak is less than the first ratio value threshold, it is determined that there is a spoofing signal in the GNSS signal;

[0032] Count the number of historical determinations within a preset time period before the current moment, add one to the number of historical determinations, and obtain the current number of determinations, wherein the number of historical determinations is the number of determinations that there are spoofing signals in the historical GNSS signals;

[0033] If the current number of determinations is greater than the determination number threshold, it is determined that there is a spoofing signal in the GNSS signal.

[0034] The beneficial effects of adopting the above-mentioned improvement scheme are: achieving continuous deceptive signal detection and improving the accuracy of detection.

[0035] Furthermore, the determination times threshold is half of the value of the preset duration.

[0036] The beneficial effects of adopting the above-mentioned improvement scheme are: being able to improve the reliability of detection and ensure the efficiency of detection.

[0037] Further, the first ratio value threshold is determined by:

[0038] Performing frequency conversion based on the acquired real signal, calculating peak values ​​of multiple correlation peaks corresponding to the real signal, and obtaining a peak set, wherein the real signal is a GNSS signal without a spoofing signal;

[0039] Based on the first peak value, the second peak value and the peak value average of the peak set, a ratio value corresponding to the first peak value and a ratio value corresponding to the second peak value are calculated, wherein the first peak value is the largest peak value in the peak set, and the second peak value is the largest peak value in the peak set except the first peak value;

[0040] A first ratio value threshold is determined according to the ratio value corresponding to the first peak value and the ratio value corresponding to the second peak value.

[0041] The beneficial effect of adopting the above-mentioned improvement scheme is: based on the correlation peak characteristics of the real signal, the first ratio value threshold is reasonably set to further improve the accuracy of detection.

[0042] In a second aspect, the present invention provides a spoof signal detection device, comprising:

[0043] An acquisition module, used to acquire GNSS signals;

[0044] The first processing module is used to perform frequency conversion on the GNSS signal to obtain intermediate frequency sampling data;

[0045] The second processing module is used to capture and process the intermediate frequency sampling data to obtain multiple correlation peaks;

[0046] A calculation module, configured to calculate a ratio value corresponding to the first peak and a ratio value corresponding to the second peak based on a peak value of the first peak, a peak value of the second peak, and an average value of peak values ​​of multiple correlation peaks, wherein the first peak is a correlation peak with a maximum peak value among the multiple correlation peaks, and the second peak is a correlation peak with a maximum peak value among the multiple correlation peaks except the first peak;

[0047] The detection module is used to determine that there is a spoofing signal in the GNSS signal if the difference between the ratio value corresponding to the first peak and the ratio value corresponding to the second peak is less than a first ratio value threshold.

[0048] In a third aspect, the present invention provides a computer-readable storage medium storing instructions, which, when executed on a terminal device, causes the terminal device to execute all or part of the steps of the spoofing signal detection method as described in the first aspect.

[0049] In a fourth aspect, the present invention provides an electronic device, comprising a memory, a processor, and a program stored in the memory and running on the processor, wherein when the processor executes the program, all or part of the steps of the spoofing signal detection method described in the first aspect are implemented. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 A schematic diagram of a flow chart of a fraud signal detection method provided by an embodiment of the present invention;

[0051] Figure 2 A schematic diagram of the structure of a spoofing signal detection device provided by an embodiment of the present invention;

[0052] Figure 3 A schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0053] The following examples are provided to further explain and supplement the present invention and do not constitute any limitation to the present invention.

[0054] A spoofing signal detection method according to an embodiment of the present invention is described below with reference to the accompanying drawings.

[0055] Reference Figure 1 As shown, the present invention provides a fraud signal detection method, comprising the following steps S1 to S5.

[0056] In step S1, a GNSS signal is acquired.

[0057] The GNSS signal is a satellite signal received by a GNSS chip in a receiver during the satellite signal capture phase.

[0058] In step S2, the GNSS signal is frequency converted to obtain intermediate frequency sampling data.

[0059] It can be understood that the intermediate frequency sampling data is the sampling data after the GNSS signal is initially stripped of the carrier.

[0060] For example, when the GNSS signal is a GPSL1 C / A signal, its carrier frequency is 1574.42MHz. After the RF chip performs preliminary carrier stripping on the GNSS signal, the frequency of the GPSL1 C / A signal will drop to about 10MHz, thereby obtaining an intermediate frequency signal; the intermediate frequency signal is sampled to obtain a digital signal of a set time length, namely, intermediate frequency sampling data.

[0061] In step S3, the intermediate frequency sampling data is captured and processed to obtain a plurality of correlation peaks.

[0062] In this embodiment, the GNSS chip performs a two-dimensional search (i.e., a code frequency two-dimensional search) on the intermediate frequency sampling data according to the set Doppler frequency and code phase to obtain the correlation results corresponding to each set Doppler frequency and code phase, and the correlation results appear as multiple correlation peaks in the three-dimensional image.

[0063] Optionally, in one embodiment, the process of capturing and processing the intermediate frequency sampling data to obtain multiple correlation peaks includes:

[0064] Based on the set multiple Doppler frequencies and the set multiple code phases, a plurality of local carriers are generated, wherein different local carriers have different Doppler frequencies or different code phases;

[0065] For each local carrier, correlation processing is performed on the local carrier and the intermediate frequency sampling data to obtain a correlation peak corresponding to the local carrier.

[0066] In this embodiment, a local numerically controlled oscillator (NCO) in the receiver generates a carrier corresponding to each Doppler frequency according to a plurality of set Doppler frequencies, wherein the plurality of Doppler frequencies can be calculated based on a preset single Doppler frequency and a preset Doppler frequency step; each carrier is modulated onto a periodic pseudo code of a plurality of set code phases to obtain a plurality of local carriers, wherein the plurality of code phases can be calculated based on a preset single code phase and a preset code phase step; all Doppler frequencies and all code phases are traversed based on the Doppler frequency step and the code phase step, that is, the local carrier is traversed according to the Doppler frequency step and the code phase step, and correlation processing is performed with the intermediate frequency signal in sequence, thereby completing a two-dimensional code frequency search and obtaining a correlation peak corresponding to the local carrier.

[0067] In step S4, based on the peak value of the first peak, the peak value of the second peak, and the average value of the peak values ​​of multiple correlation peaks, the ratio value corresponding to the first peak and the ratio value corresponding to the second peak are calculated, wherein the first peak is the correlation peak with the largest peak value among the multiple correlation peaks, and the second peak is the correlation peak with the largest peak value among the multiple correlation peaks except the first peak.

[0068] Exemplarily, there are multiple correlation peaks composed of X1, X2 and X3, and the peak values ​​of X1, X2 and X3 are 3, 2 and 1 respectively. Then, among the multiple correlation peaks, the first peak is X1 and the second peak is X2; the peak value of the multiple correlation peaks is (3+2+1) / 3, that is, 2; the corresponding ratio value of X1 is 3 / 2, that is, 1.5; the corresponding ratio value of X2 is 2 / 2, that is, 1; the corresponding ratio value of X3 is 1 / 2, that is, 0.5.

[0069] In step S5, if the difference between the ratio value corresponding to the first peak and the ratio value corresponding to the second peak is smaller than a first ratio value threshold, it is determined that there is a spoofing signal in the GNSS signal.

[0070] It is to be understood that a spoofed signal refers to a deliberately created false signal, which is usually received by a receiver together with a real signal, in order to induce the receiver to misunderstand or use the obtained signal.

[0071] In this embodiment, by continuously performing spoofing signal detection on the GNSS signal received by the GNSS chip, the appearance and disappearance of the spoofing signal can be detected in real time, which facilitates the real-time processing of the GNSS chip.

[0072] It should be noted that when there is no deception interference and only real signals (i.e., there is no deception signal in the GNSS signal), the satellite signal quality obtained by the receiver is good, that is, the correlation peak corresponding to the GNSS signal received by the receiver should satisfy the following two regular distributions:

[0073] 1. The ratio value of the first peak captured by the GNSS signal is higher, and the ratio values ​​of the second and third peaks are similar, which is significantly different from the first peak;

[0074] 2. The code phases of the first, second and third peaks are consistent, the Doppler frequencies are close, and the Doppler frequencies of the second and third peaks are symmetrical about the first peak, and the difference between them and the first peak corresponds to the Doppler frequency step.

[0075] That is to say, if there is no spoofing signal in the GNSS signal, the Doppler frequency, code phase and ratio values ​​of the first, second and third peaks obtained by the capture process satisfy the above two-point regular distribution; if there is a spoofing signal in the GNSS signal, the first, second and third peaks obtained by the capture process consist of the first peak A1 and the third peak A2 belonging to the signal with greater intensity, and the second peak B1 belonging to the signal with less intensity. The raito values ​​of the three satisfy the inequality: A1>B1>A2, and the Doppler frequency, code phase and ratio values ​​of A1 and A2 still satisfy the above two-point regular distribution.

[0076] It is understandable that if the difference in strength between the real signal and the spoofed signal is within a certain range, such as -15dB to +15dB, the strong signal does not completely suppress the weak signal, and the correlation result of the combined signal of the two still satisfies the above inequality, but the signals corresponding to A1, A2 and A3 cannot be distinguished.

[0077] In actual interference signal scenarios, the strength of deceptive signals is generally much stronger than that of real signals. In this case, A1 and A2 correspond to deceptive signals, and B1 corresponds to real signals. This enables a preliminary distinction of the signals corresponding to the three peaks in scenarios where real signals and deceptive signals coexist, so as to facilitate subsequent comparative analysis of the first peak and the third peak.

[0078] Based on the above analysis, by calculating and comparing the ratio value corresponding to the first peak with the ratio value corresponding to the second peak, it is possible to quickly distinguish whether the acquired GNSS signal is a real signal or a mixed signal (i.e., a signal containing a real signal and a spoofing signal), thereby realizing spoofing signal detection for the GNSS signal.

[0079] Optionally, in one embodiment, the spoofing signal includes at least one of a forwarding spoofing signal and a generated spoofing signal, and if the difference between the ratio value corresponding to the first peak and the ratio value corresponding to the second peak is less than a first ratio value threshold, then the implementation process of determining that the spoofing signal exists in the GNSS signal includes:

[0080] If the difference between the ratio value corresponding to the first peak and the ratio value corresponding to the second peak is less than the first ratio value threshold, the first peak is compared with the second peak to obtain a first comparison result;

[0081] If the first comparison result meets the first set condition, it is determined that there is a forwarding spoofing signal in the GNSS signal; if the first comparison result meets the second set condition, it is determined that there is a generated spoofing signal in the GNSS signal;

[0082] The first setting condition is that the Doppler frequency corresponding to the first peak is equal to the Doppler frequency corresponding to the second peak, and the difference between the code phase corresponding to the first peak and the code phase corresponding to the second peak is less than the first code phase threshold;

[0083] The second setting condition is that the difference between the Doppler frequency corresponding to the first peak and the Doppler frequency corresponding to the second peak is greater than the first Doppler frequency threshold, and the difference between the code phase corresponding to the first peak and the code phase corresponding to the second peak is greater than the second code phase threshold.

[0084] The first code phase threshold may be set to any one of 1.5 to 20 chips, such as 1.5 chips, the first Doppler frequency threshold may be set to 8 times the Doppler frequency step, and the second code phase threshold may be set to 30 chips.

[0085] It should be noted that the signal structure of the forwarding spoofing signal is completely the same as that of the real signal. The difference between the two is mainly reflected in the signal strength and signal delay. The signal delay is reflected in the correlation results as a fixed code phase lag. The signal structure of the generated spoofing signal is quite different from that of the real signal, which is reflected in the obvious differences in Doppler frequency and code phase in the correlation results. Therefore, by comparing the Doppler frequency and code phase, the forwarding spoofing signal and the generated spoofing signal can be detected respectively.

[0086] Optionally, in one embodiment, if the difference between the ratio value corresponding to the first peak and the ratio value corresponding to the second peak is less than a first ratio value threshold, before determining that there is a spoofing signal in the GNSS signal, the method further includes:

[0087] Determine a correlation peak with the largest peak value among the correlation peaks that meet a third setting condition among the multiple correlation peaks as a third peak value, wherein the third setting condition is that the peak value of the correlation peak is smaller than the peak value of the second peak value;

[0088] Based on the peak value average of the multiple correlation peaks and the peak value of the third peak, a proportion value corresponding to the third peak is calculated;

[0089] Compare the first peak and the third peak to obtain a second comparison result;

[0090] If the second comparison result does not meet the fourth setting condition, reacquiring the GNSS signal;

[0091] Among them, the fourth setting condition is that the difference between the Doppler frequency corresponding to the first peak and the Doppler frequency corresponding to the third peak is less than the second Doppler frequency threshold, the difference between the code phase corresponding to the first peak and the code phase corresponding to the third peak is less than the third code phase threshold, the difference between the proportion value corresponding to the first peak and the proportion value corresponding to the third peak is greater than the second proportion value threshold, and the proportion value corresponding to the first peak is greater than the third proportion value threshold.

[0092] In this embodiment, the fourth setting condition can be used to measure the validity of the GNSS signal, thereby improving the reliability of the detection. When the GNSS signal does not meet the fourth setting condition, such as when the signal strength of the GNSS signal is weak, the distribution of the correlation peaks obtained by the capture process will be relatively random. At this time, if the spoof signal detection is continued, it is easy to obtain an erroneous detection result.

[0093] Among them, the second Doppler frequency threshold can be set to 4 times the Doppler frequency step, the third code phase threshold can be set to 1 code chip, the second proportional value threshold can be set to 10, and the third proportional value threshold can be set to any one of 35 to 65, and is actually selected as 50. The stronger the actual signal strength, the higher the third proportional value threshold needs to be adjusted accordingly.

[0094] Optionally, in one embodiment, if the difference between the ratio value corresponding to the first peak and the ratio value corresponding to the second peak is less than a first ratio value threshold, determining that there is a spoofing signal in the GNSS signal includes:

[0095] If the difference between the ratio value corresponding to the first peak and the ratio value corresponding to the second peak is less than the first ratio value threshold, it is determined that there is a spoofing signal in the GNSS signal;

[0096] Count the number of historical determinations within a preset time period before the current moment, add one to the number of historical determinations, and obtain the current number of determinations, wherein the number of historical determinations is the number of determinations that there are spoofing signals in the historical GNSS signals;

[0097] If the current number of determinations is greater than the determination number threshold, it is determined that there is a spoofing signal in the GNSS signal.

[0098] Exemplarily, the preset duration is set to the duration used by the receiver to complete a round of satellite acquisition. Before the receiver completes this round of acquisition, it will determine in real time whether there is a spoofing signal on the GNSS signal acquired by the GNSS chip, and record the number of determinations of the presence of spoofing signals in the GNSS signal. When the receiver completes this round of acquisition, the statistical number of determinations is compared with the determination number threshold, thereby outputting the final detection result.

[0099] Optionally, the determination times threshold is half of a preset duration.

[0100] Optionally, in one embodiment, the first ratio value threshold is determined by:

[0101] Performing frequency conversion based on the acquired real signal, calculating peak values ​​of multiple correlation peaks corresponding to the real signal, and obtaining a peak set, wherein the real signal is a GNSS signal without a spoofing signal;

[0102] Based on the first peak value, the second peak value and the peak value average of the peak set, a ratio value corresponding to the first peak value and a ratio value corresponding to the second peak value are calculated, wherein the first peak value is the largest peak value in the peak set, and the second peak value is the largest peak value in the peak set except the first peak value;

[0103] A first ratio value threshold is determined according to the ratio value corresponding to the first peak value and the ratio value corresponding to the second peak value.

[0104] As a possible implementation, the first ratio value threshold=(ratio value corresponding to the first peak value−ratio value corresponding to the second peak value) / 3.

[0105] For example, in a scenario without a spoofing signal, for the GNSS signal (i.e., the real signal) received by the receiver from the same satellite, the ratio value corresponding to the first peak is 55, and the ratio value corresponding to the second peak is 22, then the first ratio value threshold = (55-22) / 3 = 11.

[0106] In the above embodiment, according to the characteristic that when a spoofing signal exists, the ratio difference between the first peak and the second peak of the GNSS signal is small, spoofing signal detection is performed based on the correlation peak, so that whether there is a spoofing signal in the GNSS signal can be detected quickly and timely. The implementation is simple and convenient for real-time processing by the GNSS chip.

[0107] In the above embodiments, although the steps are numbered, such as S1, S2, etc., these are only specific embodiments given in the present application. Those skilled in the art may adjust the execution order of S1, S2, etc. according to actual conditions, which is also within the scope of protection of the present invention. It can be understood that in some embodiments, some or all of the above embodiments may be included.

[0108] like Figure 2 As shown, a spoofing signal detection device 10 provided in an embodiment of the present invention includes:

[0109] An acquisition module 20, used for acquiring GNSS signals;

[0110] The first processing module 30 is used to perform frequency conversion on the GNSS signal to obtain intermediate frequency sampling data;

[0111] The second processing module 40 is used to capture and process the intermediate frequency sampling data to obtain multiple correlation peaks;

[0112] A calculation module 50, configured to calculate a ratio value corresponding to the first peak and a ratio value corresponding to the second peak based on a peak value of the first peak, a peak value of the second peak, and an average value of peak values ​​of multiple correlation peaks, wherein the first peak is a correlation peak with a maximum peak value among the multiple correlation peaks, and the second peak is a correlation peak with a maximum peak value among the multiple correlation peaks except the first peak;

[0113] The detection module 60 is configured to determine that a spoofing signal exists in the GNSS signal if the difference between the ratio value corresponding to the first peak and the ratio value corresponding to the second peak is less than a first ratio value threshold.

[0114] Optionally, the second processing module 40 is specifically used to generate multiple local carriers based on the set multiple Doppler frequencies and the set multiple code phases, wherein different local carriers have different Doppler frequencies or different code phases; for each local carrier, the local carrier is correlated with the intermediate frequency sampling data to obtain a correlation peak corresponding to the local carrier.

[0115] Optionally, the spoofing signal includes at least one of a forwarding spoofing signal and a generated spoofing signal. The detection module 60 is specifically used to compare the first peak with the second peak to obtain a first comparison result if the difference between the ratio value corresponding to the first peak and the ratio value corresponding to the second peak is less than a first ratio value threshold; if the first comparison result meets the first set condition, it is determined that there is a forwarding spoofing signal in the GNSS signal; if the first comparison result meets the second set condition, it is determined that there is a generated spoofing signal in the GNSS signal; the first set condition is that the Doppler frequency corresponding to the first peak is equal to the Doppler frequency corresponding to the second peak, and the difference between the code phase corresponding to the first peak and the code phase corresponding to the second peak is less than a first code phase threshold; the second set condition is that the difference between the Doppler frequency corresponding to the first peak and the Doppler frequency corresponding to the second peak is greater than the first Doppler frequency threshold, and the difference between the code phase corresponding to the first peak and the code phase corresponding to the second peak is greater than the second code phase threshold.

[0116] Optionally, the detection module 60 is also used to determine the correlation peak with the largest peak value among the correlation peaks that meet the third setting condition among the multiple correlation peaks as the third peak, wherein the third setting condition is that the peak value of the correlation peak is smaller than the peak value of the second peak; based on the peak average value of the multiple correlation peaks and the peak value of the third peak, calculate the proportion value corresponding to the third peak; compare the first peak with the third peak to obtain a second comparison result; if the second comparison result does not meet the fourth setting condition, reacquire the GNSS signal; wherein the fourth setting condition is that the difference between the Doppler frequency corresponding to the first peak and the Doppler frequency corresponding to the third peak is smaller than the second Doppler frequency threshold, the difference between the code phase corresponding to the first peak and the code phase corresponding to the third peak is smaller than the third code phase threshold, the difference between the proportion value corresponding to the first peak and the proportion value corresponding to the third peak is greater than the second proportion value threshold, and the proportion value corresponding to the first peak is greater than the third proportion value threshold.

[0117] Optionally, the detection module 60 is further used to determine that there is a spoofing signal in the GNSS signal if the difference between the proportion value corresponding to the first peak and the proportion value corresponding to the second peak is less than a first proportion value threshold; count the number of historical determinations within a preset time period before the current moment, add one to the number of historical determinations to obtain the current number of determinations, wherein the number of historical determinations is the number of determinations that there is a spoofing signal in the historical GNSS signal; if the current number of determinations is greater than the determination number threshold, it is determined that there is a spoofing signal in the GNSS signal.

[0118] Optionally, the determination times threshold is half of a preset duration.

[0119] Optionally, the detection module 60 is also used to perform frequency conversion based on the acquired real signal, calculate the peak values ​​of multiple correlation peaks corresponding to the real signal, and obtain a peak set, wherein the real signal is a GNSS signal without any spoofing signal; based on the first peak, the second peak and the peak average of the peak set, calculate the ratio value corresponding to the first peak and the ratio value corresponding to the second peak, wherein the first peak is the largest peak in the peak set, and the second peak is the largest peak in the peak set except the first peak; determine the first ratio value threshold according to the ratio value corresponding to the first peak and the ratio value corresponding to the second peak.

[0120] An embodiment of the present invention provides a computer-readable storage medium, in which instructions are stored. When the instructions are executed on a terminal device, the terminal device executes the steps of the spoofing signal detection method in any of the above embodiments.

[0121] like Figure 3 As shown, an electronic device 500 provided by an embodiment of the present invention includes a memory 510, a processor 520, and a program 530 stored in the memory 510 and running on the processor 520. When the processor 520 executes the program 530, the steps of the spoofing signal detection method of any of the above embodiments are implemented.

[0122] Among them, the electronic device 500 can be a computer, a mobile phone, etc. Correspondingly, its program 530 is a computer software or a mobile phone App, etc., and the above-mentioned parameters and steps in an electronic device 500 of the present invention can refer to the parameters and steps in the embodiment of the deception signal detection method above, and will not be repeated here.

[0123] Those skilled in the art know that the present invention can be implemented as a system, method or computer program product. Therefore, the present disclosure can be specifically implemented in the following forms, namely: it can be complete hardware, it can be complete software (including firmware, resident software, microcode, etc.), and it can also be a combination of hardware and software, which is generally referred to as "circuit", "module" or "system" herein. In addition, in some embodiments, the present invention can also be implemented in the form of a computer program product in one or more computer-readable media, and the computer-readable medium contains computer-readable program code.

[0124] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. 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 invention. 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 may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0125] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A method for detecting a spoofing signal, characterized in that: include: Acquire GNSS signals; Performing frequency conversion on the GNSS signal to obtain intermediate frequency sampling data; Capturing and processing the intermediate frequency sampling data to obtain multiple correlation peaks; Based on the peak value of the first peak, the peak value of the second peak, and the average value of the peak values ​​of the plurality of correlation peaks, a ratio value corresponding to the first peak and a ratio value corresponding to the second peak are calculated, wherein the first peak is a correlation peak with the largest peak value among the plurality of correlation peaks, and the second peak is a correlation peak with the largest peak value among the plurality of correlation peaks except the first peak; If the difference between the ratio value corresponding to the first peak and the ratio value corresponding to the second peak is less than a first ratio value threshold, it is determined that there is a spoofing signal in the GNSS signal; The first ratio value threshold is determined by: Performing frequency conversion based on the acquired real signal, calculating peak values ​​of multiple correlation peaks corresponding to the real signal, and obtaining a peak set, wherein the real signal is a GNSS signal without a spoofing signal; Based on the first peak value, the second peak value and the peak value average of the peak set, a ratio value corresponding to the first peak value and a ratio value corresponding to the second peak value are calculated, wherein the first peak value is the largest peak value in the peak set, and the second peak value is the largest peak value in the peak set except the first peak value; The first ratio value threshold is determined according to the ratio value corresponding to the first peak value and the ratio value corresponding to the second peak value.

2. The method according to claim 1, characterized in that The capturing and processing of the intermediate frequency sampling data to obtain multiple correlation peaks includes: Based on the set multiple Doppler frequencies and the set multiple code phases, generating multiple local carriers, wherein different local carriers have different Doppler frequencies or different code phases; For each of the local carriers, correlation processing is performed on the local carrier and the intermediate frequency sampling data to obtain a correlation peak corresponding to the local carrier.

3. The method according to claim 2, characterized in that The spoofing signal includes at least one of a forwarding spoofing signal and a generated spoofing signal, and if the difference between the ratio value corresponding to the first peak and the ratio value corresponding to the second peak is less than a first ratio value threshold, determining that there is a spoofing signal in the GNSS signal includes: If the difference between the ratio value corresponding to the first peak and the ratio value corresponding to the second peak is less than a first ratio value threshold, the first peak is compared with the second peak to obtain a first comparison result; If the first comparison result meets the first set condition, it is determined that there is a forwarding spoofing signal in the GNSS signal; if the first comparison result meets the second set condition, it is determined that there is a generated spoofing signal in the GNSS signal; The first setting condition is that the Doppler frequency corresponding to the first peak is equal to the Doppler frequency corresponding to the second peak, and the difference between the code phase corresponding to the first peak and the code phase corresponding to the second peak is less than a first code phase threshold; The second setting condition is that the difference between the Doppler frequency corresponding to the first peak and the Doppler frequency corresponding to the second peak is greater than a first Doppler frequency threshold, and the difference between the code phase corresponding to the first peak and the code phase corresponding to the second peak is greater than a second code phase threshold.

4. The method according to claim 2, characterized in that If the difference between the ratio value corresponding to the first peak and the ratio value corresponding to the second peak is less than a first ratio value threshold, before determining that there is a spoofing signal in the GNSS signal, the method further includes: Determine the correlation peak with the largest peak value among the correlation peaks that meet the third setting condition among the multiple correlation peaks as the third peak value, wherein the third setting condition is that the peak value of the correlation peak is smaller than the peak value of the second peak value; Based on the peak value average of the plurality of correlation peaks and the peak value of the third peak, a proportion value corresponding to the third peak is calculated; comparing the first peak and the third peak to obtain a second comparison result; If the second comparison result does not meet the fourth setting condition, reacquiring the GNSS signal; Among them, the fourth setting condition is that the difference between the Doppler frequency corresponding to the first peak and the Doppler frequency corresponding to the third peak is less than the second Doppler frequency threshold, the difference between the code phase corresponding to the first peak and the code phase corresponding to the third peak is less than the third code phase threshold, the difference between the proportion value corresponding to the first peak and the proportion value corresponding to the third peak is greater than the second proportion value threshold, and the proportion value corresponding to the first peak is greater than the third proportion value threshold.

5. The method according to claim 1, characterized in that: If the difference between the ratio value corresponding to the first peak and the ratio value corresponding to the second peak is less than a first ratio value threshold, determining that there is a spoofing signal in the GNSS signal includes: If the difference between the ratio value corresponding to the first peak and the ratio value corresponding to the second peak is less than a first ratio value threshold, it is determined that there is a spoofing signal in the GNSS signal; Counting the number of historical determinations within a preset time period before the current moment, adding one to the number of historical determinations to obtain the current number of determinations, wherein the number of historical determinations is the number of determinations that there are spoofing signals in the historical GNSS signals; If the current number of determinations is greater than the determination number threshold, it is determined that there is a spoofing signal in the GNSS signal.

6. The method according to claim 5, characterized in that The determination times threshold is half of the value of the preset time length.

7. A fraudulent signal detection device, characterized in that: include: An acquisition module, used to acquire GNSS signals; A first processing module, configured to perform frequency conversion on the GNSS signal to obtain intermediate frequency sampling data; A second processing module is used to capture and process the intermediate frequency sampling data to obtain multiple correlation peaks; a calculation module, configured to calculate a ratio value corresponding to the first peak and a ratio value corresponding to the second peak based on a peak value of the first peak, a peak value of the second peak, and an average value of peak values ​​of the plurality of correlation peaks, wherein the first peak is a correlation peak with a maximum peak value among the plurality of correlation peaks, and the second peak is a correlation peak with a maximum peak value among the plurality of correlation peaks except the first peak; a detection module, configured to determine that a spoofing signal exists in the GNSS signal if a difference between a ratio value corresponding to the first peak and a ratio value corresponding to the second peak is less than a first ratio value threshold; The invention also includes: a determination module, wherein the determination module is specifically used for: Performing frequency conversion based on the acquired real signal, calculating peak values ​​of multiple correlation peaks corresponding to the real signal, and obtaining a peak set, wherein the real signal is a GNSS signal without a spoofing signal; Based on the first peak value, the second peak value and the peak value average of the peak set, a ratio value corresponding to the first peak value and a ratio value corresponding to the second peak value are calculated, wherein the first peak value is the largest peak value in the peak set, and the second peak value is the largest peak value in the peak set except the first peak value; The first ratio value threshold is determined according to the ratio value corresponding to the first peak value and the ratio value corresponding to the second peak value.

8. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores instructions, and when the instructions are executed on a terminal device, the terminal device executes the steps of the spoofing signal detection method according to any one of claims 1 to 6.

9. An electronic device comprising a memory, a processor, and a program stored in the memory and running on the processor, characterized in that: When the processor executes the program, the steps of the spoof signal detection method according to any one of claims 1 to 6 are implemented.

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