Method, apparatus, platform and medium for identifying spoofing interference of GLS reference station

Abstract

The present invention discloses a spoofing interference recognition method, device, platform and medium for a GLS reference station. By utilizing the application feature that the position of the GLS reference station is precisely known, the present invention can identify spoofing interferences including retransmitted spoofing interference and generated spoofing interference, especially spoofing interference in a scenario without real signals, and can identify which specific signal is a spoofing interference without adding additional measurement equipment. The method is simple, does not require algorithms with high complexity such as least squares solution, and has a small computational amount. In addition, the present invention uses the geometric distance of mathematical calculation as the judgment criterion, with relatively small random errors, which is approximately 3 dB smaller than that of traditional spoofing interference recognition methods. In addition, both the miss alarm probability and the false alarm probability of spoofing interference recognition are significantly reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of visual satellite navigation, and specifically relates to GLS a spoofing interference recognition method, device, platform and medium for a reference station. Background Art

[0002] The global navigation visual satellite system ( Global Navigation Satellite System , GNSS ) has been widely applied in fields such as tourism exploration, urban traffic, aviation navigation, and precise guidance of weaponry. In particular, the approach landing system based on GNSS has received extensive attention in the aviation industry due to its characteristics such as small footprint, no need to be laid on the extended runway, simple calibration and commissioning, and support for curved approach. GNSS Landing System , GLS )

[0003] GLS It mainly consists of a reference station ( Base Station , BS ) deployed in an appropriate area of the airport, an airborne GLS receiver, and a differential and integrity data transmission radio link ( Data Link , DL ). Among them: BS mainly completes tasks such as differential data generation, integrity detection and warning, etc. The airborne GLS receiver outputs guidance information to guide the pilot or autopilot to approach and land according to the specified glide path; DL is a unidirectional data transmission radio device that sends the differential and integrity warning information generated by BS to the airborne device.

[0004] Since GNSS the landing power of the visual satellite navigation signal is weak, and the modulation coding system, ranging code structure, and air interface control protocol of the public signal are public, lawbreakers hiding near the airport can easily use illegal means such as storage and forwarding or reconstruction and regeneration to broadcast spoofing interference signals, seriously affecting the aircraft's use of GLS to operate for approach and landing, and even causing catastrophic safety accidents. Therefore, in GLS operation, it is crucial to timely and accurately identify and eliminate spoofing interference signals.

[0005] Traditional deception interference detection schemes mainly include the multi-peak detection method based on capture and the shortest signal propagation path method based on tracking. For the multi-peak detection method based on capture, its technical principle mainly relies on the autocorrelation characteristics of the signal. During the signal capture stage, a two-dimensional search method is adopted. When the time delay between the repeater deception interference and the real signal is large, multiple correlation peak values can be detected, and it is considered that there is a deception signal. However, when the time delay between the repeater deception interference and the real signal is small, or when there is only generative deception interference and no real signal, it is impossible to detect whether the current signal is a deception interference signal or a real signal. For the shortest signal propagation path method based on tracking, its technical principle mainly depends on the fact that the time for the repeater deception interference to reach the receiver is later than that of the real signal. During the tracking stage, by estimating the signal propagation time delay, that is, which signal arrives at the receiver first is considered the real signal. Similarly, this method is only applicable to identifying repeater deception interference. For generative deception interference, when there is no real signal in the scene, it is impossible to detect whether the current signal is a deception interference signal or a real signal. Existing methods all detect and identify deception interference by utilizing the differences between deception interference and real GNSS signals, and are only applicable to the scenario where deception interference signals and real signals are superimposed. When criminals use certain means (such as broadband suppression interference) to prevent all or part of the GNSS visible satellite signals around the station from being received normally, and there are only deception signals in the area, it is impossible to effectively detect deception interference signals, that is, the identification has limitations. SUMMARY OF THE INVENTION

[0006] In view of this, the purpose of the present invention is to overcome the limitations and deficiencies of traditional GNSS deception interference identification methods to solve the problems raised in the above background technology.

[0007] To achieve the above purpose, the present invention provides a GLS deception interference identification method for a reference station, including:

[0008] Step S100: Obtain the visible satellite observation information and navigation message provided by the baseband. The visible satellite observation information includes the carrier-to-noise ratio and pseudorange measurement information, and the navigation message includes satellite ephemeris and ionospheric parameters;

[0009] Step S200: Calculate the pseudorange residual value of each visible satellite through prior information. This step includes:

[0010] Step S210: Calculate the geometric distance from each visible satellite to the receiver according to the receiver position and the received satellite ephemeris. The geometric distance from the pseudorange of the m nth visible satellite to the receiver is calculated using the formula E. 1 for calculation.

[0011] (E.1)

[0012] Among them, the position of the receiver is , and the position of the m-th visible satellite is , , M is the total number of visible satellites, ;

[0013] Step S220, the step of calculating the pseudorange residual value of each visible satellite; the pseudorange residual value of the m-th visible satellite is calculated using formula E.2,

[0014] = (E.2)

[0015] Among them, represents the pseudorange measurement value of the m-th visible satellite, represents the geometric distance from the m-th visible satellite to the receiver, represents the visible satellite clock error of the m-th visible satellite, represents the ionospheric delay of the m-th visible satellite, represents the tropospheric delay of the m-th visible satellite;

[0016] According to the pseudorange residual values of all visible satellites, the pseudorange residual vector

[0017]

[0018] is obtained. The obtained pseudorange residual vector

[0019]

[0020]

[0021] (E.3)

[0022] Among them, is the error ratio of code and carrier phase, , , are constant coefficients, is the elevation angle of the m -th visible satellite, is the standard deviation of ephemeris and clock error, is the standard deviation of the ionosphere, is the standard deviation of the troposphere, is the standard deviation of the pseudocode bias, is the carrier-to-noise ratio threshold, is the m carrier-to-noise ratio of the th visible satellite,

[0023] Step S300: Use the pseudorange residual value obtained for each visible satellite for consistency verification to verify whether the visible satellite signal is a spoofing signal or a real signal, including the steps:

[0024] Step S310: Select a visible satellite as the reference satellite. Assume that the reference satellite signal is a real signal, and calculate the difference between the pseudorange residual values of the other visible satellites received by the receiver and the reference satellite, which is called the single difference. If the single difference is less than the threshold, the corresponding visible satellite signal is a real signal; otherwise, it is considered that the corresponding visible satellite signal is a spoofing signal. Obtain the signal confidence identification for each satellite according to the result of comparing the single difference with the threshold, that is, whether the visible satellite signal is a real signal or a spoofing signal; Determine whether the number of visible satellites with a signal confidence of real signal obtained is more than 4. If it is greater than or equal to 4, it is considered that the current reference satellite assumption holds, that is, the confidence levels of all signals have been correctly distinguished; If it is less than 4, it is determined that the signal of the current reference satellite is a spoofing signal, and enter step S220;

[0025] Step S320: Re-select another visible satellite as the reference satellite and repeat step S310. If after traversing all visible satellites, 4 or more visible satellites with a signal confidence of real signal are still not found, it is considered that the signals of all current visible satellites are spoofing signals.

[0026] Further, the position of the receiver is the position information in the CGCS3000 or WGS-84 coordinate system, and the acquisition means includes geodetic surveying, or 24-hour calibration, RTK calibration.

[0027] Further, the threshold value mentioned in step S310 is 60 meters.

[0028] Further, among them, the constant coefficient takes the value of 0.003, the constant coefficient takes the value of 0.003, the constant coefficient takes the value of 1.0, the standard deviation of the ephemeris and clock error takes the value of 0.5, the standard deviation of the ionosphere takes the value of 5, the standard deviation of the troposphere takes the value of 3, the standard deviation of the pseudocode offset takes the value of 0.3, the carrier-to-noise ratio threshold takes the value of 55.0.

[0029] The present invention also provides a method for differential correction and integrity detection and warning of a GLS reference station. By using the spoofing interference identification method of the GLS reference station, it further includes:

[0030] Step S400: When calculating the differential correction and integrity detection at the reference station, eliminate the spoofing signals identified in step S300, and send a spoofing signal warning to the aircraft operating takeoff and landing operations in the service area via the differential data link.

[0031] The present invention also provides a spoofing interference identification device for a GLS reference station, including a satellite information acquisition module, a pseudorange residual calculation module, and a spoofing interference identification module, where

[0032] The satellite information acquisition module is used to acquire the visible satellite observation information and navigation message provided by the baseband. The visible satellite observation information includes the carrier-to-noise ratio and pseudorange measurement information, and the navigation message includes satellite ephemeris and ionospheric parameters;

[0033] The pseudorange residual calculation module includes a distance calculation sub-module and a pseudorange residual calculation sub-module, where

[0034] The distance calculation sub-module is used to calculate the geometric distance from each visible satellite to the receiver according to the receiver position and the received satellite ephemeris information. The geometric distance from the pseudorange of the m-th visible satellite to the receiver is calculated using formula E.1,

[0035] (E.1)

[0036] where the position of the receiver is , the position of the m-th visible satellite is , , M is the total number of visible satellites, ;

[0037] The pseudorange residual calculation sub-module is used to calculate the pseudorange residual value of each visible satellite; the pseudorange residual value of the m-th visible satellite is calculated using formula E.2,

[0038] = (E.2)

[0039] where represents the pseudorange measurement value of the m -th visible satellite, represents the geometric distance from the m -th visible satellite to the receiver, represents the visible satellite clock offset of the m -th visible satellite, which is calculated from the satellite ephemeris, Indicates the ionospheric delay of the m th visible satellite, calculated based on ionospheric parameters, Indicates the tropospheric delay of the m th visible satellite;

[0040] Based on the pseudorange residuals of all visible satellites the pseudorange residual vector is obtained,

[0041]

[0042] The obtained pseudorange residual vector is weighted by formula E.3,

[0043]

[0044]

[0045] (E.3)

[0046] where is the error ratio of code and carrier phase, , , are constant coefficients, is the elevation angle of the m th visible satellite, is the standard deviation of ephemeris and clock error, is the standard deviation of the ionosphere, is the standard deviation of the troposphere, is the standard deviation of the pseudocode bias, is the carrier-to-noise ratio threshold, is the carrier-to-noise ratio of the current visible satellite, Indicates taking the maximum of both and 0;

[0047] The spoofing interference recognition module is used to perform consistency verification on the pseudorange residuals obtained for each visible satellite to verify whether the visible satellite signal is a spoofing signal or a real signal;

[0048] The consistency check is as follows: Select a visible satellite as the reference satellite. Assume that the signal of the reference satellite is a true signal. Calculate the difference between the pseudorange residuals of other visible satellites received by the receiver and the reference satellite, which is called the single difference. If the single difference is less than the threshold, the signal of the corresponding visible satellite is a true signal; otherwise, the signal of the corresponding visible satellite is considered a spoofing signal. Obtain the signal confidence identification of each satellite according to the comparison result of the single difference and the threshold, that is, whether the visible satellite signal is a true signal or a spoofing signal; Determine whether the number of visible satellites with a signal confidence of true signal obtained is more than 4. If it is greater than or equal to 4, it is considered that the current reference satellite assumption holds, that is, the confidence levels of all signals have been correctly distinguished; Select another visible satellite as the reference satellite and repeat the calculation of the single difference and comparison with the threshold. If more than 4 visible satellites with a signal confidence of true signal are not found after traversing all visible satellites, it is considered that the signals of all current visible satellites are spoofing signals.

[0049] Further, the threshold in the spoofing interference identification module is 60 meters.

[0050] The present invention also provides a GLS reference station, which adopts the spoofing interference identification device of the GLS reference station, and further includes a differential correction amount and an integrity detection and warning module.

[0051] The differential correction amount and integrity detection and warning module is used to calculate the differential correction amount and perform integrity detection and warning. When calculating the differential correction amount and integrity detection, the spoofing signals identified by the spoofing interference identification device are excluded, and a spoofing signal warning is sent to the aircraft operating takeoff and landing operations in the service area via the differential data link.

[0052] The present invention also provides a spoofing interference identification platform for a GLS reference station, including: at least one processor; and a memory communicatively connected to the at least one processor; wherein, the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the spoofing interference identification method of the GLS reference station.

[0053] The present invention also provides a computer-readable storage medium storing a computer program, and when the computer program is executed by a processor, the spoofing interference identification method of the GLS reference station is implemented.

[0054] Beneficial effects

[0055] The present invention utilizes GLSThe application features of the reference station with precisely known location. By performing consistency verification on the pseudorange residuals of each visible satellite, it can identify various types of spoofing jamming, including repeater spoofing jamming and generator spoofing jamming, especially spoofing jamming in scenarios without real signals. It can also identify which specific signal is spoofing jamming without adding additional measurement equipment. The method is simple, without the need for complex algorithms such as least squares solution, and has a small computational load. Additionally, the present invention uses the geometric distance obtained from mathematical calculations as the judgment criterion, with relatively small random errors, approximately 3 smaller than traditional spoofing jamming identification methods. dB In addition, both the miss alarm probability and false alarm probability of spoofing jamming identification are significantly reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 It is a flowchart of the spoofing jamming identification method for the GLS reference station of the present invention.

[0057] Figure 2 It is a schematic diagram of the geometric distance between the receiver and visible satellites.

[0058] Figure 3 It is a block diagram of the composition of the spoofing jamming identification device for the GLS reference station of the present invention.

[0059] Figure 4 It is a block diagram of the composition of the spoofing jamming identification platform for the GLS reference station of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0060] The following will describe in detail the specific embodiments of the present invention with reference to the accompanying drawings.

[0061] The present invention makes full use of GLS the application features of the reference station with precisely known location. Starting from the comparison of the estimated geometric distance and the measured pseudorange, it solves the problem that traditional spoofing jamming identification means cannot identify the situation where only spoofing signals exist in the environment. The present invention provides a novel GNSS spoofing jamming identification method to solve the limitations and deficiencies existing in traditional GNSS spoofing jamming identification methods.

[0062] According to the principle of visible satellite navigation and positioning, after the receiver receives all visible GNSS visible satellite signals through the antenna, by processing these signals, it can accurately measure the transmission time of each visible satellite signal. By multiplying the difference between the local time of the receiver and the measured signal transmission time by the speed of light, the distance between the receiver and the visible satellite is obtained. Since this distance includes the ionospheric delay and tropospheric delay caused by the signal passing through the atmosphere, as well as the earth rotation error, relativistic effect error, and the measurement error of the receiver itself, etc., the measured value at this time is called the pseudorange.

[0063] On the contrary, when the user's position is known, the visible satellite positions at the signal emission time can be easily obtained through the measurement information and satellite ephemeris, and then the geometric distances between each visible satellite and the receiver can be obtained (including the correction for the Earth's rotation and the relativistic effect). The ionospheric delay is calculated through the ionospheric parameters, and the tropospheric delay is calculated through the tropospheric model. After correcting the above errors, the pseudorange between each visible satellite and the receiver can be accurately estimated. By taking the difference between the estimated pseudorange and the measured pseudorange (referred to as the pseudorange residual), at this time, the error of the pseudorange residual only remains the error of the correction model itself and the error caused by the receiver noise.

[0064] To make the threshold unified, the pseudorange residuals of each visible satellite are weighted. After obtaining the weighted pseudorange residuals, one of the visible satellites is selected as the reference satellite, and the differences between the remaining visible satellites and the reference satellite are calculated, which are called single differences. At this time, the calculated single difference values of each visible satellite should be highly consistent. When the single difference value is greater than the threshold (for example, 60 meters), the corresponding visible satellite signal is a spoofing interference signal, and the signal less than the threshold is a real signal. When the current round of traversal is completed, if there are more than 4 real signals, it is considered that the traversal is completed; otherwise, the reference satellite is replaced and the traversal continues. When all visible satellite signals have been traversed and more than 4 real signals have not been found, it is considered that there are no real signals in the scenario.

[0065] Embodiment 1

[0066] This embodiment provides a GLS spoofing interference recognition method for a reference station. As Figure 1 shown, the detailed processing flow of the present invention is as follows:

[0067] Step S100: Obtain the visible satellite observation information and navigation message provided by the baseband. The visible satellite observation information includes the carrier-to-noise ratio and pseudorange measurement information, and the navigation message includes satellite ephemeris and ionospheric parameters;

[0068] Step S200: Calculate the pseudorange residual value of each visible satellite through prior information; this step includes:

[0069] Step S210: As Figure 2 shown, according to the receiver position (the receiver position, including but not limited to the position information in the 00 or RTK -84 coordinate system obtained by means such as geodetic surveying technology, 24-hour calibration, CGCS30 calibration technology, etc.) and the received satellite ephemeris, calculate the geometric distance from each visible satellite to the receiver. The geometric distance from the pseudorange of the WGS th visible satellite to the receiver is calculated using formula m 1, E. 1 is calculated,

[0070] ( E. 1)

[0071] Among them, the position of the receiver is , the m position of the visible satellite is , M , is the total number of visible satellites,

[0072] Step S220, the step of calculating the pseudorange residual value of each visible satellite; the m pseudorange residual value of the visible satellite is calculated using the formula E. 2,

[0073] = ( E. 2)

[0074] Among them, represents the m pseudorange measurement value of the visible satellite, which can be directly obtained from the visible satellite observation information provided by the baseband and the navigation message. The visible satellite measurement information specifically includes carrier-to-noise ratio, original pseudorange measurement information, carrier cycle count, etc. The navigation message includes satellite ephemeris, almanac, and ionospheric parameters; m represents the geometric distance from the visible satellite to the receiver, m represents the visible satellite clock error of the m visible satellite, and the visible satellite clock error is calculated from the satellite ephemeris; represents the m ionospheric delay of the visible satellite, and the ionospheric delay is calculated according to the ionospheric parameters,

[0075] visible satellite, and the tropospheric delay can be calculated by the Saastamoinen model; According to the pseudorange residual values

[0076]

[0077] of all visible satellites, the obtained pseudorange residual vector

[0078]

[0079]

[0080] (E.3)

[0081] Among them, is the error ratio of code and carrier phase, , , are constant coefficients, usually takes a value of 0.003, usually takes a value of 0.003, usually takes a value of 1.0, is the elevation angle of the m th visible satellite, calculated based on the receiver position and the received satellite ephemeris, is the standard deviation of ephemeris and clock error, usually taking a value of 0.5, is the standard deviation of the ionosphere, usually taking a value of 5, is the standard deviation of the troposphere, usually taking a value of 3, is the standard deviation of the pseudocode offset, usually taking a value of 0.3, is the carrier-to-noise ratio threshold, usually taking a value of 55, is the m th visible satellite's carrier-to-noise ratio, represents taking the and 0, the maximum of the two;

[0082] Step S300, using the pseudorange residual value obtained for each visible satellite for consistency verification to verify whether the visible satellite signal is a spoofing signal or a real signal, including the steps:

[0083] Step S210, select a visible satellite as the reference satellite, assume that the reference satellite signal is a real signal, calculate the difference between the pseudorange residual values of the other visible satellites received by the receiver and the reference satellite, which is called the single difference. If the single difference is less than the threshold, the corresponding visible satellite signal is a real signal, otherwise it is considered that the corresponding visible satellite signal is a spoofing signal. Obtain the signal confidence identification for each satellite according to the result of comparing the single difference with the threshold, that is, whether the visible satellite signal is a real signal or a spoofing signal; judge whether the number of visible satellites with a signal confidence of real signal obtained exceeds 4. If it is greater than or equal to 4, it is considered that the current reference satellite hypothesis holds, that is, the confidence levels of all signals have been correctly distinguished; if it is less than 4, it is determined that the signal of the current reference satellite is a spoofing signal, and enter Step S220;

[0084] Step S220, reselect another visible satellite as the reference satellite and repeat Step S310. If after traversing all visible satellites, 4 or more visible satellites with a signal confidence of real signal are not found, it is considered that the signals of all current visible satellites are spoofing signals.

[0085] The present invention is a variant based on the idea that spoofing signals will necessarily lead to position deviation. By using the method of a reference station, through geodetic surveying techniques in advance, or by using authorized signals, etc., for 24 hours or RTK After obtaining the true position of the reference station by calibration technology, when receiving spoofing signals, the idea that the information of the spoofing signals will necessarily lead to deviation in the positioning result is adopted. Moreover, the method adopted by the present invention does not use the pseudorange to calculate the current position by least squares for comparison, but indirectly obtains the authenticity of the signals through the corresponding relationship between the true position and the pseudorange, that is, if the pseudorange residual (the corresponding relationship between the true position and the pseudorange) is large, the positioning result must have a large deviation, thus reducing the calculation amount.

[0086] Embodiment 2

[0087] This embodiment provides a GLS Method for differential correction amount and integrity detection and warning of a reference station. After calculation by the method described in Embodiment 1, all spoofing signals in the GLS area can be identified. In Embodiment 2, when calculating the differential correction amount and integrity detection at the reference station, the identified spoofing signals are excluded, and a spoofing signal warning is sent to the aircraft operating takeoff and landing operations in the service area through the differential data link.

[0088] Embodiment 3

[0089] As Figure 3 shown, this embodiment provides a spoofing interference identification device for a GLS reference station, including a satellite information acquisition module, a pseudorange residual calculation module, and a spoofing interference identification module, wherein,

[0090] The satellite information acquisition module is used to acquire visible satellite observation information and navigation message provided by the baseband. The visible satellite observation information includes carrier-to-noise ratio and pseudorange measurement information, and the navigation message includes satellite ephemeris and ionospheric parameters;

[0091] The pseudorange residual calculation module includes a distance calculation sub-module and a pseudorange residual calculation sub-module, wherein,

[0092] The distance calculation sub-module is used to calculate the geometric distance from each visible satellite to the receiver according to the receiver position and the received satellite ephemeris information. The geometric distance from the pseudorange of the m th visible satellite to the receiver is calculated using the formula E. 1,

[0093] ( E. 1)

[0094] wherein, the position of the receiver is th,m The positions of the visible satellites are , , M where is the total number of visible satellites, and the positions of the visible satellites can be calculated from the satellite ephemeris;

[0095] A pseudorange residual calculation sub-module for calculating the pseudorange residuals of each visible satellite; the pseudorange residual of the m th visible satellite is calculated using the formula E. 2,

[0096] = ( E. 2)

[0097] where represents the pseudorange observation of the m th visible satellite, represents the geometric distance from the m th visible satellite to the receiver, represents the clock error of the m th visible satellite, represents the ionospheric delay of the m th visible satellite, represents the tropospheric delay of the m th visible satellite;

[0098] Based on the pseudorange residuals of all visible satellites the pseudorange residual vector is obtained,

[0099]

[0100] The obtained pseudorange residual vector is weighted using the formula E .3,

[0101]

[0102]

[0103] (E.3)

[0104] where is the error ratio of the code and carrier phase, , , are constant coefficients, usually takes the value of 0.003, usually takes the value of 0.003, Normally, the value is 1.0. is the elevation angle of the m th visible satellite, which is calculated based on the receiver position and the received satellite ephemeris. is the standard deviation of the ephemeris and clock error, and normally the value is 0.5. is the standard deviation of the ionosphere, and normally the value is 5. is the standard deviation of the troposphere, and normally the value is 3. is the standard deviation of the pseudocode bias, and normally the value is 0.3. is the carrier-to-noise ratio threshold, and normally the value is 55. is the m th visible satellite's carrier-to-noise ratio. represents taking the maximum value of both and 0.

[0105] The spoofing interference identification module is used to perform consistency verification on the pseudorange residual values obtained for each visible satellite, and verify whether the visible satellite signal is a spoofing signal or a real signal.

[0106] The consistency verification is as follows: Select a visible satellite as the reference satellite. Assume that the reference satellite signal is a real signal, and calculate the difference between the pseudorange residual values of the other visible satellites received by the receiver and the reference satellite, which is called the single difference. If the single difference is less than the threshold, the corresponding visible satellite signal is a real signal; otherwise, it is considered that the corresponding visible satellite signal is a spoofing signal. Obtain the signal confidence identification for each satellite based on the comparison result of the single difference and the threshold, that is, whether the visible satellite signal is a real signal or a spoofing signal; Determine whether the number of visible satellites with a signal confidence of real signal obtained exceeds 4. If it is greater than or equal to 4, it is considered that the current reference satellite hypothesis holds, that is, the confidence levels of all signals have been correctly distinguished; Select another visible satellite as the reference satellite and repeat the calculation of the single difference and comparison with the threshold. If more than 4 visible satellites with a signal confidence of real signal are not found after traversing all visible satellites, it is considered that all the current visible satellite signals are spoofing signals.

[0107] Preferably, the threshold in the spoofing interference identification module is 60 meters.

[0108] Furthermore, by using the GLS spoofing interference identification device of the reference station, the present invention can implement a GLS reference station. The GLS reference station further includes a differential correction amount and an integrity detection and warning module. The differential correction amount and integrity detection and warning module are used to calculate the differential correction amount and perform integrity detection and warning. When calculating the differential correction amount and integrity detection, the spoofing signals identified by the spoofing interference identification device are excluded, and a spoofing signal warning is sent to the aircraft operating takeoff and landing operations in the service area via the differential data link.

[0109] Example 4

[0110] As Figure 4 shown, this embodiment provides a GLS spoofing interference recognition platform for a reference station, including at least one processor and a memory communicatively connected to the at least one processor; wherein, the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the above-mentioned GLS spoofing interference recognition method for a reference station.

[0111] Among them, the memory and the processor are connected in a bus manner. The bus can include any number of interconnected buses and bridges, and the bus connects various circuits of one or more processors and the memory together. The bus can also connect various other circuits such as peripheral devices, voltage regulators, and power management circuits through an interface, which are well known in the art. The interface provides an interface between the bus and the transceiver, such as a communication interface and a user interface. The transceiver can be one component or multiple components, such as multiple receivers and transmitters, and provides a unit for communicating with various other devices on the transmission medium. The data processed by the processor is transmitted on the wireless medium through the antenna. Further, the antenna also receives data and transmits the data to the processor.

[0112] The processor is responsible for managing the bus and general processing, and can also provide various functions, including timing, peripheral interface, voltage regulation, power management, and other control functions. The memory can be used to store the data used by the processor when executing operations.

[0113] Example 5

[0114] This embodiment provides a computer-readable storage medium storing a computer program, and when the computer program is executed by a processor, it implements the above method embodiments.

[0115] Those skilled in the art can understand through the above description that all or part of the steps in implementing the methods of the above embodiments can be completed by instructing relevant hardware through a program. The program is stored in a storage medium, including several instructions for enabling a device (which can be a single-chip microcomputer, a chip, etc.) or a processor to execute all or part of the steps of the methods described in various embodiments of the present application. The foregoing storage medium includes, but is not limited to, various media that can store program codes such as USB flash drives, mobile hard disks, magnetic memories, and optical memories.

[0116] The above are only the preferred embodiments of the invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the ideological principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A GLS method for identifying spoofing interference of a reference station, characterized in that including Step S100: Obtain the visible satellite observation information and navigation message provided by the baseband. The visible satellite observation information includes the carrier-to-noise ratio and pseudorange measurement information, and the navigation message includes satellite ephemeris and ionospheric parameters; Step S200: Calculate the pseudorange residual value of each visible satellite through prior information; This step includes: Step S210, calculate the geometric distance from each visible satellite to the receiver according to the receiver position and the received satellite ephemeris. The geometric distance from the m th visible satellite to the receiver is calculated using the formula E.

1. ( E. 1) wherein, the position of the receiver is , the m th visible satellite's position is , , M , ; Step S220, the step of calculating the pseudorange residual value of each visible satellite; the m pseudorange residual value of the nth visible satellite is calculated using the formula E. 2 = ( E. 2) Among them, represents the pseudorange measurement value of the m th visible satellite, represents the geometric distance from the m th visible satellite to the receiver, represents the clock error of the m th visible satellite, which is calculated from the satellite ephemeris, represents the ionospheric delay of the m th visible satellite, which is calculated according to the ionospheric parameters, represents the tropospheric delay of the m th visible satellite; According to the pseudorange residual values of all visible satellites obtain the pseudorange residual vector , The obtained pseudorange residual vector is weighted by Equation E.3 (E.3) wherein, is the error ratio of code and carrier phase, , , are constant coefficients, is the elevation angle of the m th visible satellite, is the standard deviation of ephemeris and clock error, is the standard deviation of the ionosphere, is the standard deviation of the troposphere, is the standard deviation of the pseudocode offset, is the carrier-to-noise ratio threshold, is the carrier-to-noise ratio of the m th visible satellite, represents taking the and 0, whichever is the maximum; Step S300: Use the obtained pseudorange residual value of each visible satellite for consistency verification to verify whether the visible satellite signal is a spoofing signal or a real signal, including the steps of: Step S310: Select a visible satellite as the reference satellite. Assume that the signal of the reference satellite is a real signal, and calculate the difference between the pseudorange residual values of other visible satellites received by the receiver and the reference satellite, which is called the single difference. If the single difference is less than the threshold, the corresponding visible satellite signal is a real signal; otherwise, it is considered that the corresponding visible satellite signal is a spoofing signal. Obtain the signal confidence identification of each satellite according to the result of comparing the single difference with the threshold, that is, whether the visible satellite signal is a real signal or a spoofing signal; Judge whether the number of visible satellites with a signal confidence of real signal obtained is more than 4. If it is greater than or equal to 4, it is considered that the current reference satellite hypothesis holds, that is, the confidence of all signals has been correctly distinguished; If it is less than 4, it is determined that the signal of the current reference satellite is a spoofing signal, and enter Step S320; Step S320: Re-select another visible satellite as the reference satellite and repeat Step S310. If more than 4 visible satellites with a signal confidence of real signal are not found after traversing all visible satellites, it is considered that the signals of all current visible satellites are spoofing signals.

2. The GLS spoofing interference recognition method of the reference station according to claim 1, characterized in that The position of the receiver is CGCS30 00 or WGS position information in the -84 coordinate system, and the acquisition means include geodetic surveying, or 24-hour calibration, RTK calibration.

3. The GLS spoofing interference identification method for a reference station, characterized in that The threshold mentioned in Step S310 is 60 meters.

4. The GLS spoofing interference recognition method of the reference station according to claim 1, characterized in that wherein Constant coefficient The value is 0.003, the constant coefficient The value is 0.003, the constant coefficient The value is 1.0, the standard deviation of ephemeris and clock error The value is 0.5, the standard deviation of the ionosphere The value is 5, the standard deviation of the troposphere The value is 3, the standard deviation of the pseudocode offset The value is 0.3, the carrier-to-noise ratio threshold The value is 55.0 5. A GLS Differential correction amount, integrity detection and warning method for a reference station, characterized in that Using the one described in any one of claims 1-4 GLS The spoofing interference recognition method of the reference station further includes: Step S400: When calculating the differential correction amount and integrity detection at the reference station, eliminate the spoofing signals identified in Step S300, and send a spoofing signal warning to the aircraft operating takeoff and landing operations in the service area through the differential data link.

6. A GLS spoofing interference recognition device for a reference station, characterized in that including a satellite information acquisition module, a pseudorange residual calculation module, and a spoofing interference identification module, wherein The satellite information acquisition module is used to obtain the visible satellite observation information and navigation message provided by the baseband. The visible satellite observation information includes the carrier-to-noise ratio and pseudorange measurement information, and the navigation message includes satellite ephemeris and ionospheric parameters; The pseudorange residual calculation module includes a distance calculation sub-module and a pseudorange residual calculation sub-module, wherein The distance calculation sub-module is used to calculate the geometric distance from each visible satellite to the receiver according to the receiver position and the received satellite ephemeris information. The geometric distance from the pseudorange of the m th visible satellite to the receiver is calculated using the formula E.

1. ( E. 1) where the position of the receiver is , the m th visible satellite's position is , , M is the total number of visible satellites, ; The pseudorange residual calculation sub-module is used to calculate the pseudorange residuals of each visible satellite; the pseudorange residual of the m th visible satellite is calculated using the formula E. 2 = ( E. 2) Among them, represents the pseudorange measurement value of the m th visible satellite, represents the geometric distance from the m th visible satellite to the receiver, represents the clock bias of the m th visible satellite, which is calculated from the satellite ephemeris, represents the ionospheric delay of the m th visible satellite, which is calculated according to the ionospheric parameters, represents the tropospheric delay of the m th visible satellite; According to the pseudorange residual values of all visible satellites obtain the pseudorange residual vector , The obtained pseudorange residual vector is weighted by the formula E .3 (E.3) wherein, is the error ratio of code and carrier phase, , , are constant coefficients, is the elevation angle of the m th visible satellite, is the standard deviation of ephemeris and clock error, is the standard deviation of the ionosphere, is the standard deviation of the troposphere, is the standard deviation of the pseudocode offset, is the carrier-to-noise ratio threshold, is the carrier-to-noise ratio of the current visible satellite, means taking the and the maximum of both 0; The spoofing interference identification module is used to perform consistency verification on the obtained pseudorange residual value of each visible satellite to verify whether the visible satellite signal is a spoofing signal or a real signal; The consistency check is as follows: Select a visible satellite as the reference satellite. Assume that the signal of the reference satellite is a true signal. Calculate the difference between the pseudo-range residuals of other visible satellites received by the receiver and the reference satellite, which is called the single difference. If the single difference is less than the threshold, the signal of the corresponding visible satellite is a true signal; otherwise, the signal of the corresponding visible satellite is considered a spoofing signal. Obtain the signal confidence identification of each satellite according to the result of comparing the single difference with the threshold, that is, whether the visible satellite signal is a true signal or a spoofing signal; Determine whether the number of visible satellites with a signal confidence of true signal exceeds 4. If it is greater than or equal to 4, it is considered that the current reference satellite hypothesis holds, that is, the confidence of all signals has been correctly distinguished; Re-select another visible satellite as the reference satellite and repeat the calculation of the single difference and comparison with the threshold. If more than 4 visible satellites with a signal confidence of true signal are not found after traversing all visible satellites, it is considered that the signals of all current visible satellites are spoofing signals.

7. The GLS spoofing interference recognition device for a reference station, characterized in that The threshold mentioned in the spoofing interference recognition module is 60 meters.

8. A GLS reference station, characterized in that Adopt the spoofing interference recognition device of the reference station as described in claim 6 or 7, and further include a differential correction amount and an integrity detection and warning module, GLS ​ Differential correction amount and integrity detection and warning module, which is used to calculate the differential correction amount and integrity detection and warning. When calculating the differential correction amount and integrity detection, this module eliminates the spoofing signals identified by the spoofing interference recognition device and issues a spoofing signal warning to the aircraft operating takeoff and landing operations in the service area via the differential data link.

9. A GLS spoofing interference recognition platform for a reference station, characterized in that including: at least one processor; and, a memory communicatively connected to the at least one processor; wherein, The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the GLS spoofing interference identification method for a reference station as described in any one of claims 1 to 4.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the GLS spoofing interference recognition method of the reference station as described in any one of claims 1 to 4.

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