Satellite signal deception jamming method and device for satellite navigation system and satellite navigation system

Abstract

The invention discloses a satellite signal deception jamming method and device for a satellite navigation system and the satellite navigation system, and belongs to the technical field of satellite navigation application. The satellite signal deception jamming method comprises the steps that a first precision geometric factor corresponding to a first visual satellite set is obtained, the first visual satellite set is a set of a plurality of visual satellites, and the visual satellites are obtained through screening from a plurality of satellites; determining visual satellites influencing the first precision geometric factor in the first visual satellite set to obtain a target visual satellite in the first visual satellite set; acquiring a real satellite signal of the target visual satellite; generating a target deception satellite signal corresponding to the real satellite signal according to the real satellite signal and the first precision geometric factor; and sending the target deception satellite signal to a receiver. According to the invention, consumption of computing resources can be reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of satellite navigation application, in particular to a satellite signal spoofing interference method and device for a satellite navigation system and the satellite navigation system. BACKGROUND

[0002] In a satellite navigation system, a time spoofing attack is an attack mode for making a target receiver generate false time information by interfering with the time synchronization function of the target receiver. The prior art usually adopts a full-channel time spoofing attack to generate and transmit spoofing satellite signals corresponding to all real satellite signals to cover all receiving channels of the target receiver to implement the time spoofing attack. However, the prior art needs to synchronously adjust the signal parameters (such as code phase, carrier frequency and Doppler shift) of the real satellite signals corresponding to all satellites, and the above synchronous adjustment process needs to consume a large amount of computing resources. Therefore, the prior art has the problem of large consumption of computing resources. SUMMARY

[0003] The purpose of the embodiments of the present application is to provide a satellite signal spoofing interference method and device for a satellite navigation system and the satellite navigation system to solve the problem of large consumption of computing resources in the prior art.

[0004] To achieve the above purpose, the first aspect of the present application provides a satellite signal spoofing interference method for a satellite navigation system, the satellite navigation system comprising a plurality of satellites, a receiver and a spoofing device, the satellite signal spoofing interference method being executed in the spoofing device, and the satellite signal spoofing interference method comprising: obtaining a first geometric dilution of precision corresponding to a first set of visible satellites, wherein the first set of visible satellites is a set of visible satellites selected from the plurality of satellites, and the visible satellite is selected from the plurality of satellites; determining a visible satellite in the first set of visible satellites that has an influence on the first geometric dilution of precision to obtain a target visible satellite in the first set of visible satellites; obtaining a real satellite signal of the target visible satellite; generating a target spoofing satellite signal corresponding to the real satellite signal according to the real satellite signal and the first geometric dilution of precision; sending the target spoofing satellite signal to the receiver.

[0005] In the embodiments of the present application, the determination of the first visible satellite set comprises: obtaining historical satellite signal receiving data of the receiver and real-time elevation angle values of the satellites relative to the receiver; determining a preferred satellite type of the receiver according to the historical satellite signal receiving data; determining a plurality of visible satellites in the plurality of satellites according to the real-time elevation angle values, so as to obtain the first visible satellite set according to the plurality of visible satellites, wherein the visible satellite is a satellite whose real-time elevation angle value is greater than an elevation angle threshold value corresponding to a satellite of the preferred satellite type.

[0006] In the embodiments of the present application, the determination of the target visible satellite in the first visible satellite set comprises: determining a plurality of second visible satellite sets according to the first visible satellite set, wherein the second visible satellite set is a set of visible satellites remaining after a candidate visible satellite in the first visible satellite set is removed, and the candidate visible satellite is each visible satellite in the first visible satellite set; determining a second geometric dilution of precision corresponding to each second visible satellite set; determining an influence score corresponding to each candidate visible satellite according to the first geometric dilution of precision and the second geometric dilution of precision, wherein the influence score is an absolute value of a difference between the first geometric dilution of precision and the second geometric dilution of precision; and determining the target visible satellite in the plurality of candidate visible satellites according to the influence score.

[0007] In the embodiments of the present application, the determination of the target visible satellite in the plurality of candidate visible satellites according to the influence score comprises: determining a candidate visible satellite whose influence score is greater than a preset influence score in the plurality of candidate visible satellites, so as to obtain the target visible satellite.

[0008] In the embodiment of the present application, the target spoofing satellite signal corresponding to the real satellite signal is generated according to the real satellite signal and the first precision geometry factor, including: performing a first adjustment on a preset time-related parameter in the real satellite signal to obtain an initial spoofing satellite signal; obtaining a first current time offset between a current clock time of the spoofing device and a current clock time of the receiver, a current relative state parameter of the target visible satellite relative to the receiver, and a current elevation angle of the target visible satellite, wherein the current relative state parameter includes a current pseudo-range between the target visible satellite and the receiver, a current elevation angle of the target visible satellite relative to the receiver, and a second current time offset between a current clock time of the target visible satellite and a current clock time of the receiver; determining a return value corresponding to the initial spoofing satellite signal according to the first current time offset, the first precision geometry factor, and the second current time offset; determining a sum value of a product of the first current time offset, the second current time offset, the first precision geometry factor, the current relative state parameter, and the current elevation angle and a corresponding preset scoring weight coefficient to obtain an effectiveness score value corresponding to the initial spoofing satellite signal; in the case that the effectiveness score value is less than a preset effectiveness score threshold or the return value is less than a preset return value threshold, performing a second adjustment on the preset parameter in the real satellite signal until the return value corresponding to the adjusted spoofing satellite signal is greater than or equal to the preset return value threshold and the effectiveness score value corresponding to the adjusted spoofing satellite signal is greater than or equal to the preset effectiveness score threshold, to obtain the target spoofing satellite signal.

[0009] In the embodiment of the present application, the return value corresponding to the initial spoofing satellite signal is determined according to the first current time offset, the first precision geometry factor, and the second current time offset, including: obtaining a last precision geometry factor corresponding to a historical visible satellite set at a last time, a last time offset between a last clock time of the target visible satellite and a last clock time of the receiver, and a last receiver operating state parameter of the receiver at the last time; determining a deviation between the second current time offset and the last time offset to obtain a clock difference jump value; determining a precision geometry factor change rate according to the last precision geometry factor and the first precision geometry factor; and determining the return value according to the first current time offset, the clock difference jump value, the precision geometry factor change rate, and the last receiver operating state parameter.

[0010] In the embodiment of the present application, the reward value is determined according to the first current time deviation, the clock deviation jump value, the precision geometry factor change rate and the last receiver operating state parameter, including: determining a first reward value according to the first current time deviation and a preset current time deviation, wherein, in the case that the first current time deviation is greater than or equal to the preset current time deviation, the first reward value is determined as a first preset reward value, and in the case that the first current time deviation is less than the preset current time deviation, the first reward value is determined as zero; determining a second reward value according to the clock deviation jump value and a preset clock deviation jump threshold, wherein, in the case that the clock deviation jump value is less than the preset clock deviation jump threshold, the second reward value is determined as a second preset reward value, and in the case that the clock deviation jump value is greater than or equal to the preset clock deviation jump threshold, the second reward value is determined as zero; determining a third reward value according to the precision geometry factor change rate and a preset precision geometry factor change rate, wherein, in the case that the precision geometry factor change rate is less than the preset precision geometry factor change rate, the third reward value is determined as a third preset reward value, and in the case that the precision geometry factor change rate is greater than or equal to the preset precision geometry factor change rate, the third reward value is determined as zero; determining a fourth reward value according to the last receiver operating state parameter and a preset operating state parameter, wherein, in the case that the last receiver operating state parameter is equal to the preset operating state parameter, the fourth reward value is determined as zero, and in the case that the last receiver operating state parameter is not equal to the preset operating state parameter, the fourth reward value is determined as a fourth preset reward value; and determining the sum of the first reward value, the second reward value, the third reward value and the fourth reward value to obtain the reward value.

[0011] The second aspect of the present application provides a spoofing device, comprising: a memory configured to store instructions; and a processor configured to call the instructions from the memory and capable of implementing the satellite signal spoofing interference method for a satellite navigation system according to the above description when executing the instructions.

[0012] The third aspect of the present application provides a satellite navigation system, comprising: a plurality of satellites; a receiver; and a spoofing device according to the above description.

[0013] The fourth aspect of the present application provides a machine readable storage medium, which has instructions stored thereon for causing a machine to execute the satellite signal spoofing interference method for a satellite navigation system according to the above description.

[0014] The above technical solution filters the visible satellites in the first visible satellite set to obtain the target visible satellite, compared with the prior art, without adjusting the real satellite signals of all satellites, only generates the spoofing satellite signal according to the real satellite signal of the target visible satellite and the first precision geometry factor corresponding to the first visible satellite set, and sends the spoofing satellite signal to the receiver, thereby achieving time spoofing while greatly reducing the consumption of computing resources.

[0015] Other features and advantages of the embodiments of the present application will be described in the following detailed description. BRIEF DESCRIPTION OF DRAWINGS

[0016] The accompanying drawings are included to provide a further understanding of the embodiments of the present application, and constitute a part of the specification, and are used to explain the embodiments of the present application together with the following detailed description, but are not used to limit the embodiments of the present application. In the drawings: Figure 1 A flowchart schematically showing a satellite signal spoofing interference method for a satellite navigation system according to an embodiment of the present application is shown; Figure 2 A structural schematic diagram of a satellite navigation system according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0017] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. It should be understood that the specific embodiments described herein are merely used to explain and illustrate the embodiments of the present application, and are not used to limit the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of the present application.

[0018] It should be noted that the acquisition, transmission, storage, use, processing and the like of data in the technical solutions of the present application comply with relevant provisions of laws and regulations. In the embodiments of the present application, some industry existing solutions, components, models and the like may be mentioned, which should be considered as exemplary, and the purpose is only to illustrate the feasibility of the implementation of the technical solutions of the present application, but does not mean that the applicant has or will necessarily use the solutions.

[0019] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement condition and the like between components in a certain specific posture (as shown in the drawings), and if the specific posture changes, the directional indications also change accordingly.

[0020] In addition, if the description of "first", "second", etc. is involved in the embodiments of the present application, the description of "first", "second", etc. is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can be explicitly or implicitly included at least one of the features. In addition, the technical solutions of various embodiments can be combined with each other, but it must be based on the realization of ordinary skilled in the art, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor in the protection scope required by the present application.

[0021] Figure 1 The flowchart of the satellite signal spoofing interference method for the satellite navigation system according to the embodiments of the present application is schematically shown. As shown in Figure 1 The embodiments of the present application provide a satellite signal spoofing interference method for a satellite navigation system, the satellite navigation system includes a plurality of satellites, a receiver and a spoofing device, the satellite signal spoofing interference method is executed in the spoofing device, and the satellite signal spoofing interference method can include the following steps: Step S101, obtaining a first geometric dilution of precision corresponding to a first visible satellite set, wherein the first visible satellite set is a set of a plurality of visible satellites, and the visible satellite is selected from the plurality of satellites.

[0022] Step S102, determining the visible satellite in the first visible satellite set which has an influence on the first geometric dilution of precision, to obtain the target visible satellite in the first visible satellite set.

[0023] Step S103, obtaining the real satellite signal of the target visible satellite.

[0024] Step S104, generating the target spoofing satellite signal corresponding to the real satellite signal according to the real satellite signal and the first geometric dilution of precision.

[0025] Step S105, sending the target spoofing satellite signal to the receiver.

[0026] It can be understood that the first visible satellite set is a set of multiple visible satellites, and the visible satellites are selected from multiple satellites. A geometric dilution of precision (GDOP) is used to represent a parameter of a degree of influence of a geometric position relationship between the satellite set and the receiver on positioning accuracy. The first geometric dilution of precision is used to represent a degree of influence of a geometric position relationship between the first visible satellite set and the receiver on positioning accuracy. The target visible satellite is a visible satellite in the first visible satellite set that has an influence on the first geometric dilution of precision. The real satellite signal is a satellite signal sent by the target visible satellite without human modification. The target spoofing satellite signal is a false satellite signal similar to the real satellite signal, and is used to induce the receiver to calculate incorrect positioning, navigation or timing information. The spoofing device is a device for generating a spoofing satellite signal based on a real satellite signal. The spoofing device can receive real satellite signals of multiple satellites and generate target spoofing satellite signals corresponding to the real satellite signals. In the case that the receiver receives real satellite signals of multiple satellites, the spoofing device can send the spoofing satellite signals to the receiver to interfere with the receiver's accurate acquisition of the time of the satellite signals, so that there is a certain time deviation between the clock time of the receiver and the standard clock time, thereby achieving time spoofing.

[0027] Specifically, the first geometric dilution of precision corresponding to the first visible satellite set is obtained, wherein the determination method of the first geometric dilution of precision is that the spoofing device can pre-acquire the three-dimensional position relationship between each visible satellite in the first visible satellite set and the receiver, thereby constructing an observation matrix according to the three-dimensional position relationship corresponding to each visible satellite, determining the cofactor matrix corresponding to the observation matrix, and then determining the trace of the inverse matrix corresponding to the cofactor matrix, and taking the trace as the first geometric dilution of precision corresponding to the first visible satellite set. Then, the visible satellites in the first visible satellite set that have an influence on the first geometric dilution of precision are determined, and the target visible satellite in the first visible satellite set can be obtained. Further, the real satellite signal of the target visible satellite is obtained, and the spoofing device can generate the target spoofing satellite signal corresponding to the real satellite signal based on the pre-set reinforcement learning algorithm according to the real satellite signal and the first geometric dilution of precision, and send the target spoofing satellite signal to the receiver to achieve time spoofing.

[0028] Through the above technical solution, the visible satellites in the first visible satellite set are selected to obtain the target visible satellite. Compared with the prior art, it is not necessary to adjust the real satellite signals of all satellites, but only the target spoofing satellite signal is generated according to the real satellite signal of the target visible satellite and the first geometric dilution of precision corresponding to the first visible satellite set, and the target spoofing satellite signal is sent to the receiver, thereby achieving time spoofing while greatly reducing the consumption of computing resources.

[0029] In the embodiments of the present application, the determination of the first visible satellite set can comprise: obtaining historical satellite signal receiving data of the receiver, and real-time elevation angle values of the satellites relative to the receiver; determining a preferred satellite type of the receiver according to the historical satellite signal receiving data; and determining a plurality of visible satellites in the plurality of satellites according to the real-time elevation angle values, so as to obtain the first visible satellite set according to the plurality of visible satellites, wherein the visible satellite is a satellite whose real-time elevation angle value is greater than an elevation angle threshold value corresponding to the preferred satellite type.

[0030] It can be understood that the historical satellite signal receiving data is satellite signal receiving data received by the receiver for a long time, for example, NMEA-0183 protocol data, which can include but is not limited to satellite identification information, positioning results, and clock difference. The real-time elevation angle value is an elevation angle value of the satellite relative to the receiver at the current time. The preferred satellite type is a satellite type preferred by the receiver, for example, a low-elevation satellite type or a high-elevation satellite type. The visible satellite is a satellite that can be observed by the receiver and receive effective signals.

[0031] Specifically, the spoofing device obtains the historical satellite signal receiving data of the receiver, the real-time elevation angle values of the satellites relative to the receiver, and determines the preferred satellite type of the receiver according to the historical satellite signal receiving data based on a clustering algorithm or other classification analysis method. The processor can also construct the association between the receiver and the historical satellite signal receiving data, and determine the preferred satellite type of the receiver according to the association. Further, the elevation angle threshold value corresponding to the satellite of the preferred satellite type is determined, and the plurality of satellites are screened according to the elevation angle threshold value. The satellite whose real-time elevation angle value is greater than the elevation angle threshold value corresponding to the satellite of the preferred satellite type is taken as a visible satellite, so as to obtain the first visible satellite set based on the plurality of visible satellites.

[0032] After screening the plurality of satellites, the visible satellites are obtained, and the invisible satellites whose signals cannot directly reach the receiver are screened out, and at the same time, the real satellite signals of all satellites are avoided to be adjusted, so that excessive unnecessary computing resources are not consumed.

[0033] In the embodiments of the present application, the visible satellites in the first visible satellite set that have an influence on the first geometric dilution of precision can be determined to obtain target visible satellites in the first visible satellite set, which can include: determining a plurality of second visible satellite sets according to the first visible satellite set, wherein the second visible satellite set is a set of visible satellites remaining after removing a candidate visible satellite in the first visible satellite set, and the candidate visible satellite is each visible satellite in the first visible satellite set; determining a second geometric dilution of precision corresponding to each second visible satellite set; determining an influence score corresponding to each candidate visible satellite according to the first geometric dilution of precision and the second geometric dilution of precision, wherein the influence score is an absolute value of a difference between the first geometric dilution of precision and the second geometric dilution of precision; and determining target visible satellites in the plurality of candidate visible satellites according to the influence score.

[0034] It can be understood that the second visible satellite set is a set of visible satellites remaining after removing a candidate visible satellite in the first visible satellite set. The candidate visible satellite is each visible satellite in the first visible satellite set. The second geometric dilution of precision is used to represent the influence degree of the geometric position relationship between the second visible satellite set and the receiver on the positioning accuracy. The influence score is used to represent the influence degree of the candidate visible satellite on the precision combination factor of the first visible satellite set, and the influence score is an absolute value of a difference between the first geometric dilution of precision and the second geometric dilution of precision.

[0035] Specifically, the spoofing device determines a plurality of second visible satellite sets according to the first visible satellite set, the second visible satellite set is a set of visible satellites remaining after removing a candidate visible satellite from the first visible satellite set, and a second geometric dilution of precision of the second visible satellite set is determined, so as to determine an absolute value of a difference between the first geometric dilution of precision and the second geometric dilution of precision to obtain an influence score of each candidate visible satellite. Then, the target visible satellite in the candidate visible satellite is determined according to the influence score.

[0036] By calculating the first geometric dilution of precision and the second geometric dilution of precision, the influence score of each candidate visible satellite is determined, the influence degree of each candidate visible satellite on the first geometric dilution of precision corresponding to the first visible satellite set is determined, and the target visible satellite is screened to lay a physical foundation for subsequent implementation of high-precision time spoofing.

[0037] In the embodiments of the present application, the target visible satellite in the plurality of candidate visible satellites can be determined according to the influence score, which can include: determining a candidate visible satellite in the plurality of candidate visible satellites whose influence score is greater than a preset influence score to obtain the target visible satellite.

[0038] It can be understood that the preset influence score is a preset influence score.

[0039] Specifically, the deception device can take the candidate visible satellites with the influence score greater than the preset influence score as the target visible satellites. The deception device can also determine the target visible satellites from the candidate visible satellites according to the influence score in combination with the real-time elevation angle value, which is not limited here. That is, the deception device screens out the visible satellites (visible satellites with low timing accuracy) that have an impact on the first precision geometry factor, and adjusts the real satellite signal of the visible satellites, so as to obtain the deception signal corresponding to the real satellite signal, reduces the loss of computing resources, and achieves the effect of time deception.

[0040] In the embodiment of the present application, the target deception satellite signal corresponding to the real satellite signal is generated according to the real satellite signal and the first precision geometry factor, which can include: performing a preliminary adjustment on the preset time-related parameters in the real satellite signal to obtain an initial deception satellite signal; obtaining a first current time deviation between the current clock time of the deception device and the current clock time of the receiver, a current relative state parameter of the target visible satellite relative to the receiver, and a current elevation angle of the target visible satellite, wherein the current relative state parameter includes a current pseudo-range between the target visible satellite and the receiver, a current elevation angle of the target visible satellite relative to the receiver, and a second current time deviation between the current clock time of the target visible satellite and the current clock time of the receiver; determining a return value corresponding to the initial deception satellite signal according to the first current time deviation, the first precision geometry factor, and the second current time deviation; determining a sum value of the product of the first current time deviation, the second current time deviation, the first precision geometry factor, the current relative state parameter, and the current elevation angle with the corresponding preset scoring weight coefficient, to obtain an effectiveness score value corresponding to the initial deception satellite signal; in the case that the effectiveness score value is less than a preset effectiveness score threshold or the return value is less than a preset return value threshold, adjusting the preset parameters in the real satellite signal again until the return value corresponding to the adjusted deception satellite signal is greater than or equal to the preset return value threshold and the effectiveness score value corresponding to the adjusted deception satellite signal is greater than or equal to the preset effectiveness score threshold, to obtain the target deception satellite signal.

[0041] It can be understood that the preset time-related parameter is a signal parameter related to time in the real satellite signal, for example, code phase, carrier frequency, etc. The initial spoofing satellite signal is a false satellite signal artificially initially generated and highly similar to the real satellite signal, and is used to interfere with the normal acquisition of time by the receiver. The first current time offset is a time offset between the current clock time of the spoofing device and the current clock time of the receiver. The current relative state parameter is a state parameter between the target visible satellite and the receiver at the current time, and the current relative state parameter includes the current pseudorange between the target visible satellite and the receiver, the current elevation angle of the target visible satellite relative to the receiver, and the second current time offset (clock difference) between the current clock time of the target visible satellite and the current clock time of the receiver. The return value is a parameter value for evaluating the effect feedback of the preset parameter adjustment of the real satellite signal. The initial spoofing satellite signal obtained after the real satellite signal is adjusted is able to achieve the effect of time spoofing, at which time the return value is a positive value, and if the initial spoofing satellite signal is unable to achieve the effect of time spoofing or triggers the alarm of the receiver, the return value is a negative value. The preset score weight coefficient is a preset score weight coefficient. The effectiveness score value is used to evaluate the score value of each parameter for the effectiveness of achieving time spoofing at the current time. The preset effectiveness score threshold is a preset effectiveness score threshold.

[0042] Specifically, the spoofing device first sets the preset parameters, the preset effectiveness score threshold, and the preset score weight coefficient, facilitating subsequent parameter calculation. The spoofing device initially adjusts the preset parameters in the real satellite signal of the target visible satellite to obtain the initial spoofing satellite signal, and obtains the first current time offset between the current clock time of the spoofing device and the current clock time of the receiver, the current relative state parameter of the target visible satellite relative to the receiver, and the current elevation angle of the target visible satellite. According to the first current time offset, the first geometric dilution of precision, and the second current time offset, the return value corresponding to the initial spoofing satellite signal is determined. The spoofing device can determine the sum of the product values of the first current time offset, the second current time offset, the first geometric dilution of precision, the current relative state parameter, and the current elevation angle and the corresponding preset score weight coefficient, to obtain the effectiveness score value corresponding to the initial spoofing satellite signal; the spoofing device can also construct a matrix of the first current time offset, the second current time offset, the first geometric dilution of precision, the current relative state parameter, and the current elevation angle, determine the matrix value corresponding to the matrix, and determine the matrix value as the effectiveness score value. In the case that the effectiveness score value is less than the preset effectiveness score threshold or the return value is less than the preset return value threshold, the preset parameters in the real satellite signal are adjusted again until the return value corresponding to the adjusted spoofing satellite signal is greater than or equal to the preset return value threshold and the effectiveness score value corresponding to the adjusted spoofing satellite signal is greater than or equal to the preset effectiveness score threshold, to obtain the target spoofing satellite signal.

[0043] Through continuous adjustment of preset parameters of the real satellite signal, the target spoofing satellite signal corresponding to the real satellite signal is generated, which can interfere with the receiver and achieve the effect of time spoofing.

[0044] In the embodiment of the present application, the return value corresponding to the initial spoofing satellite signal is determined according to the first current time deviation, the first geometric dilution of precision factor and the second current time deviation, comprising: obtaining the last geometric dilution of precision factor corresponding to the historical visible satellite set, the last time deviation between the last clock time of the target visible satellite and the last clock time of the receiver, and the last receiver operating state parameter of the receiver at the last moment; determining the deviation between the second current time deviation and the last time deviation to obtain the clock difference jump value; determining the geometric dilution of precision factor change rate according to the last geometric dilution of precision factor and the first geometric dilution of precision factor; determining the return value according to the first current time deviation, the clock difference jump value, the geometric dilution of precision factor change rate and the last receiver operating state parameter.

[0045] It can be understood that the historical visible satellite set is the set of visible satellites received by the receiver at the last moment. The last geometric dilution of precision factor, the last time deviation and the last receiver operating state parameter are the geometric dilution of precision factor corresponding to the historical visible satellite set, the last time deviation between the last clock time of the target visible satellite and the last clock time of the receiver, and the last receiver operating state parameter of the receiver obtained at the last moment, respectively. The clock difference jump value is the change amount of the clock difference at the current moment (the second current time deviation) and the clock difference at the last moment (the last time deviation). The geometric dilution of precision factor change rate is the change rate of the first geometric dilution of precision factor and the last geometric dilution of precision factor. The last receiver operating state parameter is the operating state parameter of the receiver at the last moment, the normal operating state parameter is 0, and the abnormal operating state parameter is 1, wherein the abnormal operating state includes receiver alarm (for example, Receiver Autonomous Integrity Monitoring (RAIM) failure).

[0046] Specifically, the deception device obtains the last accuracy geometry factor corresponding to the historical visible satellite set at the last time, the last time deviation of the last clock time of the target visible satellite and the last clock time of the receiver, and the last receiver operating state parameter of the receiver, and respectively determines the clock deviation jump value and the accuracy geometry factor change rate, so as to determine the return value according to the first current time deviation, the clock deviation jump value, the accuracy geometry factor change rate and the last receiver operating state parameter. The above technical scheme can effectively determine the effect of the preset parameter adjustment of the real satellite signal at the last time according to the first current time deviation, the clock deviation jump value, the accuracy geometry factor change rate and the last receiver operating state parameter, so as to optimize the adjustment strategy of the preset parameter of the real satellite signal at the current time, and improve the effectiveness and concealment of time deception.

[0047] In the embodiment of the present application, the return value is determined according to the first current time deviation, the clock deviation jump value, the accuracy geometry factor change rate and the last receiver operating state parameter, including: determining a first return value according to the first current time deviation and a preset current time deviation, wherein in the case that the first current time deviation is greater than or equal to the preset current time deviation, the first return value is determined as a first preset return value, and in the case that the first current time deviation is less than the preset current time deviation, the first return value is determined as zero; determining a second return value according to the clock deviation jump value and a preset clock deviation jump threshold, wherein in the case that the clock deviation jump value is less than the preset clock deviation jump threshold, the second return value is determined as a second preset return value, and in the case that the clock deviation jump value is greater than or equal to the preset clock deviation jump threshold, the second return value is determined as zero; determining a third return value according to the accuracy geometry factor change rate and a preset accuracy geometry factor change rate, wherein in the case that the accuracy geometry factor change rate is less than the preset accuracy geometry factor change rate, the third return value is determined as a third preset return value, and in the case that the accuracy geometry factor change rate is greater than or equal to the preset accuracy geometry factor change rate, the third return value is determined as zero; determining a fourth return value according to the last receiver operating state parameter and a preset operating state parameter, wherein in the case that the last receiver operating state parameter is equal to the preset operating state parameter, the fourth return value is determined as zero, and in the case that the last receiver operating state parameter is not equal to the preset operating state parameter, the fourth return value is determined as a fourth preset return value; and determining the sum of the first return value, the second return value, the third return value and the fourth return value to obtain the return value.

[0048] It can be understood that the first preset return value is a preset first return value, for example, +100, the second preset return value is a preset second return value, for example, +5, the third preset return value is a preset third return value, for example, +10, and the fourth preset return value is a preset fourth return value, for example, -50. The preset current time deviation is a preset current time deviation. The preset clock jump threshold is a preset clock jump threshold, for example, 0.3 The preset precision geometry factor change rate is a preset precision geometry factor change rate, for example, 10%.

[0049] Specifically, the spoofing device can compare the size of the first current time deviation and the preset current time deviation, and determine that the first return value is the first preset return value (for example, +100) in the case that the first current time deviation is greater than or equal to the preset current time deviation, indicating that the purpose of time spoofing can be achieved, and determine that the first return value is zero in the case that the first current time deviation is less than the preset current time deviation, indicating that the purpose of time spoofing cannot be achieved. The spoofing device can also compare the size of the clock jump value and the preset clock jump threshold, and determine that the second return value is the second preset return value in the case that the clock jump value is less than the preset clock jump threshold, the clock jump value is low, and the receiver can be avoided to trigger the detection of time anomaly, and determine that the second return value is zero in the case that the clock jump value is greater than or equal to the preset clock jump threshold, the clock jump value is high, and the receiver is easy to trigger the detection of time anomaly. The spoofing device can also compare the size of the precision geometry factor change rate and the preset precision geometry factor change rate, and determine that the third return value is the third preset return value in the case that the precision geometry factor change rate is less than the preset precision geometry factor change rate, indicating that the precision geometry factor change rate is small, which is consistent with the normal expectation of the receiver for the precision geometry factor change rate, and will not trigger the alarm of the receiver, thereby ensuring the concealment of time spoofing; and determine that the third return value is zero in the case that the precision geometry factor change rate is greater than or equal to the preset precision geometry factor change rate, indicating that the precision geometry factor change rate is large, which is easy to trigger the alarm of the receiver. The spoofing device can also compare whether the last receiver operating state parameter is consistent with the preset operating state parameter, and determine that the fourth return value is zero in the case that the last receiver operating state parameter is equal to the preset operating state parameter, and determine that the fourth return value is the fourth preset return value in the case that the last receiver operating state parameter is not equal to the preset operating state parameter. Further, the sum of the first return value, the second return value, the third return value and the fourth return value is determined to obtain the return value.

[0050] By comparing the first current time deviation, the clock jump value, the precision geometry factor change rate and the last receiver operating state parameter with the corresponding preset threshold, the corresponding return value is determined, which is convenient for subsequent optimization of the adjustment of the preset parameters of the real satellite signal.

[0051] In one specific embodiment, as shown in Figure 2 The satellite navigation system 200 includes a plurality of satellites 201, a receiver 202, and a spoofing device 203, the receiver 202 can receive the real satellite signals of the plurality of satellites 201 through the receiving antenna 204, the spoofing device 203 can receive the real satellite signals of the plurality of satellites 201 through the receiving antenna 204, generate spoofing satellite signals corresponding to the real satellite signals, and send them to the receiver 202 through the transmitting antenna 205. The receiver can receive the spoofing satellite signals sent by the spoofing device 203 through the transmitting antenna 205 while receiving the real satellite signals of the plurality of satellites 201 through the receiving antenna 204. Based on this, the spoofing satellite signals can interfere with the receiver 202 to obtain accurate time, so that the clock time of the receiver and the standard clock time have a certain deviation, achieving the effect of time spoofing.

[0052] The technical solution of the present application is that the spoofing device 203 can pre-acquire a first precision geometric factor corresponding to a first visible satellite set, and determine a target visible satellite in the first visible satellite set. According to the real satellite signal and the first precision geometric factor, the target spoofing satellite signal corresponding to the real satellite signal is continuously generated, so as to send the target spoofing satellite signal to the receiver 202 through the transmitting antenna 205, interfere with the receiver 202, gradually change the time deviation between the clock time of the receiver and the standard clock time, and thus realize time spoofing.

[0053] The determination process of the first visible satellite set is as follows: acquiring the historical satellite signal receiving data (historical satellite selection data) of the receiver, the real elevation angle values of each satellite relative to the receiver, and based on the clustering algorithm, clustering and analyzing the historical satellite signal receiving data to determine the preferred satellite type of the receiver. The spoofing device can also mine the preferred satellite type of the receiver by drawing a scatter plot of the GDOP value and the average satellite elevation angle. In this way, a plurality of visible satellites in the plurality of satellites can be determined according to the real elevation angle value, so as to obtain the first visible satellite set according to the plurality of visible satellites, wherein the visible satellite is a satellite whose real elevation angle value is greater than the elevation angle threshold value corresponding to the satellite of the preferred satellite type.

[0054] The method for determining the target visible satellite is: assuming that the first visible satellite set includes A, B, C, D and E five visible satellites, then five second visible satellite sets (ABCD, ABCE, ABDE, ACDE and BCDE) can be obtained, and the second precision geometric factors corresponding to the five second visible satellite sets are calculated (2.1, 2.5, 2.6, 2.7 and 2.0 respectively); according to the first precision geometric factor (for example, 2.4) and each second precision geometric factor, the influence score corresponding to each candidate visible satellite is determined, wherein the influence score is the absolute value of the difference between the first precision geometric factor and the second precision geometric factor; the candidate visible satellites whose influence scores (0.3, 0.1, 0.2, 0.3, 0.4) are greater than the preset influence score (for example, 0.2) in the plurality of candidate visible satellites are determined, to obtain the target visible satellite (E, B and A).

[0055] The attack sequence is optimized based on the reinforcement learning algorithm (Q-Learning) to avoid triggering the abnormal detection of the receiver, such as the GDOP mutation alarm. The deception device selects a target visible satellite as the attacked object, and obtains the first current time deviation between the current clock time of the deception device and the current clock time of the receiver, the current relative state parameter of the target visible satellite relative to the receiver and the current elevation angle of the target visible satellite in real time, wherein the current relative state parameter includes the current pseudo-range between the target visible satellite and the receiver, the current elevation angle of the target visible satellite relative to the receiver, the second current time deviation between the current clock time of the target visible satellite and the current clock time of the receiver, and the above-mentioned first current time deviation, current elevation angle, current pseudo-range, current elevation angle and second current time deviation are taken as the current state. The deception device can pre-set the expected state, i.e. the preset parameters corresponding to the first current time deviation, current elevation angle, current pseudo-range, current elevation angle and second current time deviation, and can also pre-set the preset score weight coefficients corresponding to the first current time deviation, second current time deviation, first precision geometric factor, current relative state parameter and current elevation angle, determine the effectiveness score value corresponding to the current state, and determine the preset effectiveness score threshold value corresponding to the expected state.

[0056] Based on - Greedy policy selects action: with probability Explore random action, otherwise select the maximum Q value action, dynamically adjust : initial = 0.7 (high exploration), decaying to 0.1 (high exploitation) over training epochs, and the initial adjustment of the preset parameters (e.g., clock bias, replacement PRN08 satellite signal, or software radio transmission modification code phase / carrier frequency) in the real satellite signal to obtain the initial spoofing satellite signal is performed in the case that the validity score value is less than a preset validity score threshold or the return value is less than a preset return value threshold, in order to evaluate the concealment, effect of the parameter adjustment, and whether an alarm is triggered, the return value (reward value) corresponding to the initial spoofing satellite signal is determined according to the first current time deviation, the first precision geometry factor, and the second current time deviation, and further adjustment of the preset parameters in the real satellite signal is continued according to the return value until the return value corresponding to the adjusted spoofing satellite signal is greater than or equal to the preset return value threshold and the validity score value corresponding to the adjusted spoofing satellite signal is greater than or equal to the preset validity score threshold, so as to obtain the target spoofing satellite signal.

[0057] The specific manner of determining the return value corresponding to the initial spoofing satellite signal according to the first current time deviation, the first precision geometry factor, and the second current time deviation includes: obtaining the last precision geometry factor corresponding to the historical visible satellite set, the last time deviation between the last clock time of the target visible satellite and the last clock time of the receiver, and the last receiver operating state parameter of the receiver at the last moment, determining the deviation between the second current time deviation and the last time deviation to obtain a clock bias jump value, determining a precision geometry factor change rate according to the last precision geometry factor and the first precision geometry factor, and determining the return value according to the first current time deviation, the clock bias jump value, the precision geometry factor change rate, and the last receiver operating state parameter. In the case that the first current time deviation is greater than or equal to a preset current time deviation (1 second), the first return value is determined to be a first preset return value (+100), otherwise, the first return value is 0. In the case that the clock bias jump value is less than a preset clock bias jump threshold (0.3 ), the second return value is determined to be a second preset return value (+5), otherwise, the second return value is 0. In the case that the precision geometry factor change rate is less than a preset precision geometry factor change rate (10%), the third return value is a third preset return value (+10), otherwise, the third return value is 0. In the case that the last receiver operating state parameter is not equal to a preset operating state parameter (receiver alarm, such as RAIM failure), the fourth return value is determined to be a fourth preset return value (-50), otherwise, the fourth return value is 0. The sum of the first return value, the second return value, the third return value, and the fourth return value is determined to obtain the return value.

[0058] The deception device is combined with the synchronous compensation unit, adopts a phase-locked loop (PLL) and a delay-locked loop (DLL) technology, tracks real signal parameters in real time, adjusts a target deception satellite signal phase and a power gradient, and transmits the signal to a receiver.

[0059] The technical effects achieved by the technical scheme include: first, by gradually replacing key satellite signals, an optimal GDOP false appearance is artificially constructed, a receiver actively selects an attacked satellite (a target visible satellite), and traditional multi-system cross verification can be avoided. Second, only a specific frequency band (such as GPS L1) or a small number of target visible satellites are attacked, other channel signals are normal, power abnormalities and signal conflicts of full-channel attacks are avoided. Third, target deception satellite signals and real satellite signals are strictly synchronized in code phase and carrier frequency, and can bypass signal quality monitoring (SQM) and time difference of arrival (TDOA) detection. Fourth, in combination with a satellite selection strategy, a key satellite (a target visible satellite) is determined, and a high-precision synchronous deception signal (including a fake navigation message, a code phase, and a Doppler frequency shift) is generated for the key satellite, partial-channel deception signals are broadcast, hardware costs are reduced, and computing resources are greatly reduced.

[0060] The embodiments of the present application further provide a deception device, comprising: a memory configured to store instructions; and a processor configured to call the instructions from the memory and capable of implementing the satellite signal deception interference method for a satellite navigation system according to the above when executing the instructions.

[0061] The embodiments of the present application further provide a satellite navigation system, comprising: a plurality of satellites; a receiver; and a deception device according to the above.

[0062] The embodiments of the present application further provide a machine readable storage medium, which stores instructions for causing a machine to execute the satellite signal deception interference method for a satellite navigation system according to the above.

[0063] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system or a computer program product. Therefore, the present application can adopt a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can adopt a computer program product in the form of one or more computer usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer usable program code.

[0064] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks. Figure 1 one or more flow or blocks Figure 1 means for functionally implementing the steps in the flowchart block or blocks

[0065] These computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture including instructions which implement the function specified in the flowchart block or blocks. Figure 1 one or more flow or blocks Figure 1 means for functionally implementing the steps in the flowchart block or blocks

[0066] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks. Figure 1 one or more flow or blocks Figure 1 means for functionally implementing the steps in the flowchart block or blocks

[0067] In one typical configuration, the computing device includes one or more processors (CPUs), input / output interfaces, network interfaces, and memory.

[0068] The memory can include non-persistent memory and / or volatile memory, such as random access memory (RAM) and / or cache memory, for storing instructions and data used and / or generated by the computing device. The memory can also include non-volatile memory, such as read-only memory (ROM), electrically programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory, or nonvolatile random access memory (RAM) (e.g., fault tolerant RAM), for storing instructions and data used and / or generated by the computing device. The memory is an example of computer readable media.

[0069] Computer-readable media includes permanent and non-permanent, movable and non-movable media that can implement information storage by any method or technology. The information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassette, disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information accessible to a computing device. According to the definition herein, computer-readable media does not include transitory media such as modulated data signals and carriers.

[0070] It should also be noted that the terms "comprising", "containing", or any other variant thereof are intended to cover non-exclusive inclusions, so that a process, method, article or apparatus that includes a list of elements does not only include those elements, but also includes other elements not explicitly listed, or further includes elements inherent in such a process, method, article or apparatus. Without more limitations, the element defined by the statement "comprising a" does not exclude the presence of additional identical elements in the process, method, article or apparatus that includes the element.

[0071] The above only is an embodiment of the present application, and is not used to limit the present application. For those skilled in the art, the present application can have various changes and variations. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application shall be included in the scope of claims of the present application.

Claims

1. A method for spoofing and jamming satellite signals in a satellite navigation system, characterized in that, The satellite navigation system includes multiple satellites, a receiver, and a deception device. The satellite signal deception jamming method is executed on the deception device, and the satellite signal deception jamming method includes: Obtain the first precision geometric factor corresponding to the first set of visible satellites, wherein the first set of visible satellites is a set of multiple visible satellites, and the visible satellites are selected from the multiple satellites; Identify the visible satellites in the first set of visible satellites that affect the first precision geometric factor, so as to obtain the target visible satellites in the first set of visible satellites; Obtain the actual satellite signals of the target's visible satellites; Based on the real satellite signal and the first precision geometric factor, a target deception satellite signal corresponding to the real satellite signal is generated; The target sends the deception satellite signal to the receiver.

2. The method according to claim 1, characterized in that, The determination of the first visible satellite set includes: The receiver acquires historical satellite signal reception data and the real-time elevation angle of each satellite relative to the receiver. Based on the historical satellite signal reception data, the preferred satellite type of the receiver is determined; Based on the real-time elevation angle value, multiple visible satellites are determined from among the multiple satellites to obtain a first set of visible satellites, wherein the visible satellites are satellites whose real-time elevation angle value is greater than the elevation angle threshold value corresponding to the preferred satellite type.

3. The method according to claim 1, characterized in that, The step of determining the visible satellites in the first set of visible satellites that affect the first precision geometric factor, in order to obtain the target visible satellites in the first set of visible satellites, includes: Multiple second visible satellite sets are determined based on the first visible satellite set, wherein the second visible satellite set is a set of visible satellites remaining after removing candidate visible satellites from the first visible satellite set, and the candidate visible satellites are each visible satellite in the first visible satellite set; Determine the second precision geometric factor corresponding to each of the second visible satellite sets; Based on the first precision geometric factor and each of the second precision geometric factors, the influence score corresponding to each of the candidate visible satellites is determined, wherein the influence score is the absolute value of the difference between the first precision geometric factor and the second precision geometric factor; Based on the influence score, the target visible satellite is determined from among the multiple candidate visible satellites.

4. The method according to claim 3, characterized in that, The step of determining the target visible satellite among the multiple candidate visible satellites based on the influence score includes: The target visible satellite is obtained by identifying candidate visible satellites whose influence scores are greater than a preset influence score among a plurality of candidate visible satellites.

5. The method according to claim 1, characterized in that, The step of generating the target deception satellite signal corresponding to the real satellite signal based on the real satellite signal and the first precision geometric factor includes: The preset time-related parameters in the real satellite signal are initially adjusted to obtain an initial deception satellite signal; The system acquires a first current time deviation between the current clock time of the deception device and the current clock time of the receiver, the current relative state parameters of the target visible satellite relative to the receiver, and the current elevation angle of the target visible satellite. The current relative state parameters include the current pseudorange between the target visible satellite and the receiver, the current elevation angle of the target visible satellite relative to the receiver, and a second current time deviation between the current clock time of the target visible satellite and the current clock time of the receiver. The reward value corresponding to the initial spoofing satellite signal is determined based on the first current time deviation, the first precision geometric factor, and the second current time deviation; The sum of the products of the first current time deviation, the second current time deviation, the first precision geometric factor, the current relative state parameter, and the current elevation angle with their respective preset scoring weight coefficients is determined to obtain the effectiveness score value corresponding to the initial deceiving satellite signal. If the validity score is less than a preset validity score threshold or the reward value is less than a preset reward value threshold, the preset parameters in the real satellite signal are readjusted until the reward value corresponding to the adjusted deceitful satellite signal is greater than or equal to the preset reward value threshold and the validity score value corresponding to the adjusted deceitful satellite signal is greater than or equal to the preset validity score threshold, so as to obtain the target deceitful satellite signal.

6. The method according to claim 5, characterized in that, The step of determining the reward value corresponding to the initial spoofing satellite signal based on the first current time deviation, the first precision geometric factor, and the second current time deviation includes: The previous precision geometric factor corresponding to the historical visible satellite set at the previous moment, the previous time deviation between the previous clock time of the target visible satellite and the previous clock time of the receiver, and the previous receiver operating status parameters of the receiver are obtained. Determine the deviation between the second current time deviation and the previous time deviation to obtain the clock error jump value; The rate of change of the precision geometric factor is determined based on the previous precision geometric factor and the first precision geometric factor; The report value is determined based on the first current time deviation, the clock error jump value, the rate of change of the precision geometric factor, and the operating status parameters of the previous receiver.

7. The method according to claim 6, characterized in that, The step of determining the report value based on the first current time deviation, the clock error jump value, the rate of change of the precision geometric factor, and the operating status parameters of the previous receiver includes: A first reward value is determined based on the first current time deviation and the preset current time deviation, wherein if the first current time deviation is greater than or equal to the preset current time deviation, the first reward value is determined to be a first preset reward value, and if the first current time deviation is less than the preset current time deviation, the first reward value is determined to be zero. A second reward value is determined based on the clock difference jump value and a preset clock difference jump threshold. If the clock difference jump value is less than the preset clock difference jump threshold, the second reward value is determined to be a second preset reward value. If the clock difference jump value is greater than or equal to the preset clock difference jump threshold, the second reward value is determined to be zero. A third reward value is determined based on the rate of change of the precision geometric factor and the preset rate of change of the precision geometric factor. Wherein, if the rate of change of the precision geometric factor is less than the preset rate of change of the precision geometric factor, the third reward value is determined to be a third preset reward value. If the rate of change of the precision geometric factor is greater than or equal to the preset rate of change of the precision geometric factor, the third reward value is determined to be zero. Based on the previous receiver operating status parameters and the preset operating status parameters, a fourth report value is determined. Wherein, if the previous receiver operating status parameters are equal to the preset operating status parameters, the fourth report value is determined to be zero. If the previous receiver operating status parameters are not equal to the preset operating status parameters, the fourth report value is determined to be a fourth preset report value. The sum of the first return value, the second return value, the third return value, and the fourth return value is determined to obtain the return value.

8. A deception device, characterized in that, include: The memory is configured to store instructions; as well as The processor is configured to retrieve the instructions from the memory and, when executing the instructions, to implement the satellite signal deception and jamming method for a satellite navigation system according to any one of claims 1 to 7.

9. A satellite navigation system, characterized in that, include: Multiple satellites; Receiver; The deception device according to claim 8.

10. A machine-readable storage medium, characterized in that, The machine-readable storage medium stores instructions for causing the machine to perform a satellite signal deception and jamming method for a satellite navigation system according to any one of claims 1 to 7.

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