GPS interference warning and positioning method and system based on operator base station

Abstract

The present invention provides a GPS interference early warning and positioning method and system based on an operator base station, which relates to the field of wireless communication technology. The method obtains the ADS-B data, QAR data and flight trajectory data of the aircraft during the interference period, identifies the time point of GPS signal loss and recovery, determines the aircraft interference area, and judges the time characteristics of the interference signal; according to the time characteristics of the interference signal, the signal receiving power and gain difference of the interference signal data received by the base station during the interference period are analyzed to determine the vector direction of the interference source signal; through the interference signal vector directions of multiple base stations and the signal strength of the interference source, the precise position of the interference source in three-dimensional space is calculated, and by constructing a three-dimensional space model of the area where the interference source is located, the influence area of ​​the interference source is simulated. Real-time monitoring, early warning and positioning of GPS interference sources are achieved.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication technology, and in particular to a GPS interference early warning and positioning method and system based on an operator base station. Background Art

[0002] As the global positioning system (GPS) is widely used in aviation, navigation, logistics and other fields, the security and reliability of GPS have become key factors in ensuring flight safety. In recent years, GPS interference incidents have occurred frequently, especially during aircraft flight. Loss or interference of GPS signals may cause deviation from the flight trajectory and even cause flight accidents. Therefore, how to accurately warn and effectively locate the source of GPS interference has become a difficult problem that needs to be solved in the field of aviation safety.

[0003] Traditional GPS interference source location methods usually rely on single signal data from aircraft's own equipment or ground stations for interference monitoring. This method has certain limitations, such as the inability to accurately identify the direction of the signal source, low accuracy in calculating the location of the interference source, and long response time for interference events. In addition, a single interference signal analysis method is easily affected by environmental and weather factors, resulting in inaccurate interference source identification or a high risk of missed reports or false alarms.

[0004] With the widespread application of operator base stations in the field of wireless communications, base station data has been gradually introduced into GPS interference monitoring. Operator base stations can provide multi-point signal data for the location of interference sources, and effectively help locate the location of interference sources by analyzing the signal strength differences between base stations. Compared with traditional methods, interference source positioning based on operator base stations can make full use of the synergy between base stations and combine with aircraft flight data to provide more accurate and real-time interference source positioning and warning information.

[0005] However, the existing technology lacks a GPS interference warning and positioning system that can accurately combine base station signals, aircraft flight trajectory data, and multi-dimensional analysis. The existing technology usually only relies on the data of the aircraft's GPS receiver or a single ground station, and it is difficult to fully cover the precise positioning and warning of interference sources. Therefore, how to design a system based on operator base station data fusion, interference signal detection, precise positioning and warning has become a core technical challenge in solving the GPS interference problem. Summary of the invention

[0006] In view of this, the purpose of the present invention is to propose a GPS interference warning and positioning method and system based on an operator base station, which aims to effectively identify, warn and prevent GPS interference through precise interference source positioning, real-time data collection and multi-source information fusion, ensure the safety of aircraft during flight, and utilize the existing communication infrastructure combined with real-time monitoring to achieve real-time monitoring, warning and positioning of GPS interference sources. It has the advantages of low cost, high coverage, strong real-time performance and high positioning accuracy, and can be widely used in various fields requiring high-precision navigation and positioning, and is particularly important for ensuring the security of GPS signals in public safety, traffic management, military defense and other fields.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] Based on the above purpose, in a first aspect, the present invention provides a GPS interference warning and positioning method based on an operator base station, comprising the following steps:

[0009] Obtain the aircraft's ADS-B data, QAR data and flight trajectory data during the interference period;

[0010] Based on the aircraft's flight trajectory and ADS-B data, determine the points where the aircraft's GPS position was lost and regained during the interference period, and combine it with QAR data to identify the time points when the GPS signal was lost and restored;

[0011] Determine the interference area of ​​the aircraft based on the flight trajectory data of the aircraft and the position loss points and position recovery points during the interference period;

[0012] Based on the distribution topology information of base stations and the determined interference area, collect the interference signal data received by the operator base stations in the area, and match the interference signal data, ADS-B data, QAR data and flight trajectory data in the time dimension to determine the time characteristics of the interference signal;

[0013] Analyze the signal receiving power and gain difference of the interference signal data received by the base station during the interference period according to the time characteristics of the interference signal, and determine the vector direction of the interference source signal;

[0014] By measuring the signal strength of the interference signal in different antenna sectors of each base station during the interference period, the signal strength of the interference source is calculated, and the precise position of the interference source in three-dimensional space is calculated through the interference signal vector direction of multiple base stations and the signal strength of the interference source;

[0015] Based on the precise location of the interference source, combined with the spatial information of the GPS position loss points and position recovery points during the aircraft flight, as well as the signal data of multiple base stations, a three-dimensional spatial model of the area where the interference source is located is constructed, the impact area of ​​the interference source is simulated, and interference source warning information is generated.

[0016] As a further solution of the present invention, according to the flight trajectory of the aircraft and the ADS-B data, determining the GPS position loss point and position recovery point of the aircraft during the interference period includes the following steps:

[0017] The acquired aircraft ADS-B data, QAR data and flight trajectory data are synchronized in time and mapped into a unified time sequence through timestamp alignment;

[0018] By comparing the GPS coordinates in the ADS-B data with the heading and speed information in the QAR data, it is determined whether the GPS signal is lost;

[0019] If the jump amplitude between multiple consecutive position points in the ADS-B data exceeds the preset jump threshold, the position jumps and GPS signal loss occurs;

[0020] If the speed change recorded in the QAR data differs from the speed reported by the ADS-B by more than the preset speed difference threshold, the speed is abnormal and GPS signal loss has occurred;

[0021] In ADS-B data, when the GPS signal is lost for a period of time and then restored, and the restored trajectory is consistent with the route, and the speed in the QAR data matches the restored GPS data, the GPS position is considered to be restored, and the position loss point and position recovery point are identified and recorded to form the boundary of the interference period.

[0022] As a further solution of the present invention, when determining whether the GPS signal is lost, if the displacement between two consecutive ADS-B records is , and the time interval between two consecutive ADS-B records is ,when Greater than the preset threshold When , it means that the GPS signal is lost. The lost point means that the plane distance formula under the geodetic coordinate system is used to calculate the straight-line distance between the two points. The calculation formula is:

[0023]

[0024] In the formula, It is the position difference between two consecutive ADS-B records, indicating the distance between the two points; and Represent the longitude coordinates in the first ADS-B record and the longitude coordinates in the second ADS-B record respectively; and Represents the latitude coordinate in the first ADS-B record and the latitude coordinate in the second ADS-B record, respectively.

[0025] As a further solution of the present invention, in combination with QAR data, identifying the time points of GPS signal loss and recovery includes the following steps:

[0026] Get the speed, altitude and attitude information of QAR data;

[0027] Based on the QAR data, if the parameters of speed, altitude and attitude information change abnormally, the GPS signal is lost, and the position loss point is marked and recorded; when the flight parameters in the QAR data return to normal, combined with the smooth trajectory changes in the ADS-B data, the time point of GPS signal recovery is confirmed, and the position recovery point is marked and recorded;

[0028] By comparing and analyzing the ADS-B data, the exact time points of GPS signal loss and recovery are calibrated. The timestamps in the QAR data are aligned with the start and end times of the interference period to accurately calibrate the time points of loss and recovery.

[0029] As a further solution of the present invention, determining the aircraft interference area includes the following steps:

[0030] Determine the latitude and longitude, timestamp, altitude, speed and heading information of the aircraft during the interference period based on the acquired flight trajectory data;

[0031] After the aircraft data is synchronized, the time point and position loss point (GPS failure point) of the aircraft GPS signal loss during the interference period are determined by comparing the ADS-B and QAR data, and the time point and position recovery point (GPS recovery point) of the GPS signal recovery are determined;

[0032] The flight segment of the aircraft is determined based on the geometry of the route and the position loss and position recovery points during the interference period. The starting and ending points of the interference area are determined on the route based on the route and the start and end positions of the interference period. The boundary of the interference area is formed by the position loss point (track point at the time of GPS loss) and the position recovery point (track point at the time of GPS recovery).

[0033] The interference area of ​​the aircraft is determined by judging the spatial overlap between the interference area and the actual flight trajectory, and an interference area report is generated, where the interference area report includes:

[0034] The start and end points of the interference area: including the GPS signal loss point and recovery point during the interference period;

[0035] Overlapping part of the route and the interference area: Indicates the specific location where the route and the interference area overlap;

[0036] The geometry and extent of the interference area: It is marked by polygonal or rectangular areas to give the spatial distribution of the interference area.

[0037] As a further solution of the present invention, the aircraft route is composed of multiple track segments, including a track segment from the starting point of the segment to the lost point, a track segment from the lost point to the re-picking point, and a track segment from the re-picking point to the end point of the segment. Each track segment is fitted with a spline curve through the track points of the aircraft to obtain the accurate boundary of the interference area, and the longitude and latitude of the lost point and the re-picking point during the interference period, as well as the result of the route fitting, are used to calculate the spatial range of the interfered area; wherein the boundary of the interfered area of ​​the straight segment is calculated by the longitude and latitude of the starting and ending points of the segment; the boundary of the interfered area of ​​the curved path is judged based on the route equation of the spline curve fitting and the boundary points within a set distance on both sides of the spline curve.

[0038] As a further solution of the present invention, the distribution topology information of the base station includes the latitude and longitude coordinates of the base station location and the signal coverage range, and the interference area is predicted and drawn through the signal coverage range of the base station, and the interference area is the overlapping part of the area covered by multiple base stations; when the interference area is predicted through the signal coverage range of the base station, the following steps are included:

[0039] According to the latitude and longitude coordinates of the base station location and the signal attenuation model, the boundary of the base station interference area is obtained;

[0040] Collect interference signal data through the base station within the determined interference area of ​​the aircraft and the boundary of the interference area of ​​the base station, including the strength, frequency and time stamp of the interference signal;

[0041] Align the interference signal data collected by the base station, the ADS-B data of the aircraft, the QAR data and the flight trajectory data in the time dimension;

[0042] Once the data is aligned in the time dimension, the time characteristics of the interference signal are analyzed according to the flight trajectory and the interference signal received by the base station, and the duration of the interference signal, the rate of change of the interference signal strength and the fluctuation characteristics of the interference signal are picked up;

[0043] Combine the flight trajectory data with the time characteristics of the interference signal data to find the overlap between the flight and the interference area, and analyze whether the flight path crosses the interference area;

[0044] By statistically analyzing the temporal characteristics of multiple interference events, the patterns of interference signals are extracted, and the occurrence frequency, duration distribution and intensity variation trend of interference signals are determined.

[0045] As a further solution of the present invention, when the boundary of the base station interference area is obtained according to the latitude and longitude coordinates of the base station location and the signal attenuation model, the calculation of the base station interference area is based on the signal attenuation model of the base station, and the attenuation of the signal strength at a set distance is calculated through the transmission power and signal attenuation factor of the interference source, and the range of the interference area is estimated, wherein the distance when the signal strength attenuates to the threshold is the radius of the base station interference area, and the calculation formula is:

[0046]

[0047] In the formula, is the distance when the signal strength decays to the threshold, i.e., the radius of the base station interference area; is the transmission power of the interference source; is the path loss factor, which indicates the degree of loss during signal propagation.

[0048] As a further solution of the present invention, determining the vector direction of the interference source signal includes the following steps:

[0049] Collect the interference signal power received by the base station during the flight of the aircraft, including timestamp, received signal strength and gain data, and filter out the time period when the interference signal strength exceeds the preset threshold;

[0050] According to the received interference signal strength data, the change rate of the interference signal is calculated to identify the sudden interference of the signal;

[0051] Based on the known receiving antenna gain of the base station, the direction of the interference source is calculated through the gain difference, and the distance of the interference source relative to the base station is obtained based on the signal strength and gain difference, and the direction of the interference source is further estimated;

[0052] When multiple base stations receive the same interference signal, triangulation is used to measure the difference in the strength of the interference signals received by different base stations. Based on the signal strength received by each base station, the distance from the interference source to each base station is estimated, and the least squares method is used to obtain the position of the interference source, the direction of the interference source is estimated, and the vector direction of the interference source signal is obtained in combination with the estimated direction of the interference source.

[0053] As a further solution of the present invention, when estimating the direction of the interference source, the distance between the interference source and the base station is calculated by the signal strength, wherein the received signal strength The calculation formula is:

[0054]

[0055] In the formula, is the received signal strength, unit: dBm; The transmission power of the interference source, in dBm, is the power of the signal transmitting end when the interference source transmits the signal; is the path loss index, the product of the path loss index Controls the rate of signal attenuation, that is, the amplitude of signal strength attenuation per unit distance increase. In a free space environment, , which indicates the degree of signal attenuation as the distance increases; It is a constant of the product of the path loss exponent, which indicates the attenuation of the signal strength when the signal propagates in space for each additional unit distance (such as each additional meter or kilometer), that is, the relationship between the amplitude of the path loss and the logarithmic change of the propagation distance. The path loss exponent The rate at which the signal is attenuated is affected. The more complex the environment is and the more obstacles there are, The larger the value of ; is the distance from the interference source to the receiving base station, in meters; It is the distance The logarithm of reflects the characteristic that the signal strength decreases with the increase of distance, and the signal attenuation follows the logarithmic law;

[0056] When the transmission power is known , path loss index and the distance from the interference source to the receiving base station When the received signal strength can be calculated Similarly, if the received signal strength is known , Transmit power and path loss exponent , the distance from the interference source to the receiving base station can also be calculated , the calculation formula is:

[0057]

[0058] The above formula can be used to infer the location of the interference source based on the signal strength, or to estimate the characteristics of signal propagation.

[0059] As a further solution of the present invention, when constructing a three-dimensional spatial model of an interference source, the spatial position of the interference source is calculated by combining the signal strength data and the aircraft position data received by the base station, and the positioning accuracy of the interference source is corrected based on the calculated interference source coordinates and the propagation model of the interference signal, and a three-dimensional model of the area where the interference source is located is constructed according to the spatial coordinates, indicating the position of the interference source in the three-dimensional space and the influence range;

[0060] When the back propagation model is used to infer the spatial position of the interference source, the geometric relationship between the interference source and the base station and the aircraft is calculated in the spatial coordinate system, where the calculation formula for the distance from the base station to the interference source is:

[0061]

[0062] In the formula, For base station Distance to the interference source; ( , , ) is the base station The spatial coordinates of , , ) is the spatial coordinate of the interference source;

[0063] When constructing a three-dimensional model of the area where the interference source is located, a three-dimensional spherical model of the area is constructed by defining the radius of the area affected by the interference source. The radius calculation formula of the area affected by the interference source is:

[0064]

[0065] In the formula, is the radius of the interference source impact area, that is, the radius of the base station interference area; is the transmission power of the interference source; is the path loss factor, which indicates the degree of loss during signal propagation.

[0066] In a second aspect, the present invention provides a GPS interference warning and positioning system based on an operator base station, comprising the following components:

[0067] Data acquisition module, used to obtain ADS-B data, QAR data and flight trajectory data of aircraft during interference periods;

[0068] The interference signal detection module is used to determine the GPS position loss and position recovery points of the aircraft during the interference period based on the aircraft's flight trajectory and ADS-B data, and identify the time points of GPS signal loss and recovery in combination with QAR data;

[0069] The regional positioning module is used to determine the interference area of ​​the aircraft based on the flight trajectory data of the aircraft and the position loss points and position recovery points during the interference period;

[0070] The time feature matching module is used to collect interference signal data received by the operator base stations in the area based on the distribution topology information of the base stations and the determined interference area, and match the interference signal data, ADS-B data, QAR data and flight trajectory data in the time dimension to determine the time characteristics of the interference signal;

[0071] The interference source positioning module is used to calculate the signal strength of the interference source by measuring the signal strength of the interference signal in different antenna sectors of each base station during the interference period, and calculate the precise position of the interference source in three-dimensional space through the interference signal vector direction of multiple base stations and the signal strength of the interference source;

[0072] The three-dimensional spatial modeling module is used to construct a three-dimensional spatial model of the area where the interference source is located based on the precise location of the interference source, combined with the spatial information of the GPS position loss point and position recovery point during the aircraft flight, and the signal data of multiple base stations, simulate the impact area of ​​the interference source, and generate interference source warning information.

[0073] Compared with the prior art, the GPS interference warning and positioning method and system based on the operator base station proposed in the present invention has the following beneficial effects:

[0074] 1. The present invention can accurately locate the interference source and combine the real-time flight data of the aircraft to give early warning before the interference source has an impact, effectively reducing the flight safety risks caused by the loss of GPS signals. Through the real-time data collection of base station signals, the position change of the interference source can be dynamically monitored, and the position of the interference source in three-dimensional space can be accurately calculated by analyzing the interference signals of multiple base stations. This real-time monitoring and dynamic tracking capability makes the positioning of the interference source no longer static, but dynamically adjusted as the interference source moves, ensuring the high accuracy of the interference source positioning.

[0075] 2. The present invention can calculate the precise location of the interference source through the analysis of the interference signal data received by the base station, the flight trajectory of the aircraft, and the position loss point and the re-gain point, and further construct a three-dimensional space model, and use the signal strength difference between multiple base stations to perform accurate calculations through a three-dimensional positioning algorithm, which significantly improves the accuracy of interference source positioning compared to the traditional single base station positioning method. By performing multi-dimensional fusion analysis of ADS-B data, QAR data, flight trajectory data and interference signal data received by the base station, the fault tolerance of the system under various complex interference conditions is improved. When the signal quality of a certain base station is poor, the system can still locate and track the interference source through other base station data, ensuring the stability and robustness of the system under different conditions.

[0076] 3. The present invention can generate detailed interference source warning information based on the positioning results of the interference source, and send alarms to aviation management departments, aircraft and other relevant parties in a timely manner. By obtaining information such as the location of the interference source, signal strength and impact range in advance, aviation management personnel can formulate countermeasures to reduce the impact of interference on navigation. The early warning mechanism can be deployed in advance before the interference source causes interference, thereby providing aircraft with sufficient emergency response time. By constructing a three-dimensional spatial model of the area where the interference source is located, the propagation law of the interference signal in different environments can be accurately simulated, and its impact range can be predicted. This is of great significance for aircraft route planning, further control of interference sources, and aviation safety management.

[0077] In summary, the GPS interference warning and positioning method and system based on the operator base station of the present invention not only effectively improves the accuracy of interference source positioning, but also provides a strong guarantee for the safe flight of aircraft. Through the comprehensive application of high-precision positioning, multi-source data fusion, three-dimensional space modeling and interference source warning technologies, it can significantly reduce aviation safety accidents caused by GPS interference and improve the accuracy and response speed of aviation management.

[0078] These and other aspects of the present application will be more concise and understandable in the following description of the embodiments. It should be understood that the above general description and the following detailed description are only exemplary and explanatory and cannot limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0079] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the following briefly introduces the drawings required for use in the exemplary embodiments or related technical descriptions. The drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation to the present invention. In the drawings:

[0080] Figure 1 The present invention is a flowchart of a method for GPS interference warning and positioning based on an operator base station according to an embodiment of the present invention.

[0081] Figure 2 The present invention is a flowchart of determining a position loss point and a position recovery point in a GPS interference warning and positioning method based on an operator base station in an embodiment of the present invention.

[0082] Figure 3 The present invention is a flowchart of determining an aircraft interference area in a GPS interference warning and positioning method based on an operator base station in an embodiment of the present invention.

[0083] Figure 4The present invention is a flowchart of predicting interference areas through signal coverage of base stations in a GPS interference warning and positioning method based on operator base stations in an embodiment of the present invention.

[0084] Figure 5 The present invention is a flowchart of determining the vector direction of an interference source signal in a GPS interference warning and positioning method based on an operator base station in an embodiment of the present invention. DETAILED DESCRIPTION

[0085] Below, the present application is further described in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form a new embodiment.

[0086] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the embodiments of the present invention are further described in detail below in combination with specific embodiments and with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0087] It should be noted that all expressions using "first" and "second" in the embodiments of the present invention are intended to distinguish two non-identical entities or non-identical parameters with the same name. It can be seen that "first" and "second" are only for the convenience of expression and should not be understood as limitations on the embodiments of the present invention. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, other steps or units inherent to a process, method, system, product or device that includes a series of steps or units.

[0088] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0089] The flowcharts shown in the accompanying drawings are only examples and do not necessarily include all the contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps may also be decomposed, combined or partially merged, so the actual execution order may change according to actual conditions.

[0090] In conjunction with the accompanying drawings, some embodiments of the present application are described in detail below. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0091] In view of the problem that the existing technology only relies on the data of the aircraft's GPS receiver or a single ground station, it is difficult to fully cover the precise positioning and early warning of interference sources. The present invention proposes a GPS interference early warning and positioning method and system based on an operator base station, which aims to effectively identify, warn and prevent GPS interference through accurate interference source positioning, real-time data collection and multi-source information fusion, ensure the safety of aircraft during flight, and use the existing communication infrastructure combined with real-time monitoring to achieve real-time monitoring, early warning and positioning of GPS interference sources. It has the advantages of low cost, high coverage, strong real-time performance and high positioning accuracy, and can be widely used in various fields requiring high-precision navigation and positioning, especially to ensure the security of GPS signals in public safety, traffic management, military defense and other fields.

[0092] See also Figure 1 As shown, an embodiment of the present invention provides a GPS interference warning and positioning method based on an operator base station, the method comprising the following steps:

[0093] Step S10: Acquire the ADS-B data, QAR data and flight trajectory data of the aircraft during the interference period.

[0094] In this step, the multi-dimensional data of the aircraft at different time periods during the flight are obtained, including ADS-B data, QAR data and flight trajectory data as follows:

[0095] ADS-B data: includes the aircraft's GPS coordinates, speed, heading and timestamp information.

[0096] QAR data: flight parameters including speed, altitude and attitude.

[0097] Flight trajectory data: records the flight path of an aircraft, provided by the airline or air traffic control department.

[0098] The above data can be obtained based on the flight monitoring platform provided by the air traffic control system or the airline, or directly collected through sensors on the aircraft.

[0099] Step S20: Determine the GPS position loss point and position recovery point of the aircraft during the interference period based on the flight trajectory and ADS-B data of the aircraft, and identify the time points of GPS signal loss and recovery in combination with QAR data.

[0100] In this step, see Figure 2 As shown, according to the flight trajectory of the aircraft and ADS-B data, the GPS position loss point and position recovery point of the aircraft during the interference period are determined: including the following steps:

[0101] Step S201: synchronize the acquired aircraft's ADS-B data, QAR data, and flight trajectory data in time, and map them into a unified time sequence through timestamp alignment;

[0102] Step S202: Determine whether the GPS signal is lost by comparing the GPS coordinates in the ADS-B data with the heading and speed information in the QAR data;

[0103] By analyzing the GPS coordinates in the ADS-B data and the heading and speed information in the QAR data, it is determined whether the GPS signal is lost. Specifically:

[0104] If the jump amplitude between multiple consecutive position points in the ADS-B data exceeds the preset jump threshold (for example, greater than 200 meters), the position jumps and GPS signal loss occurs;

[0105] If the speed change recorded in the QAR data differs from the speed reported by the ADS-B by more than a preset speed difference threshold (e.g., greater than 20 knots), the speed is abnormal and GPS signal loss has occurred;

[0106] Step S203: In the ADS-B data, when the GPS signal is lost for a period of time and then restored, and the restored trajectory is consistent with the route, and the speed in the QAR data matches the restored GPS data, it is considered that the GPS position is restored, and the position loss point and the position recovery point are identified and recorded to form the boundary of the interference period.

[0107] According to the GPS signal loss and recovery time points determined in step S202 and step S205, the start and end time of the interference period, i.e., the boundary of the interference period, is defined. The exact time point of the interference period is precisely calibrated by comparing and analyzing the ADS-B data and QAR data and combining the timestamp alignment.

[0108] Among them, when judging whether the GPS signal is lost, if the displacement between two consecutive ADS-B records is , and the time interval between two consecutive ADS-B records is ,when Greater than the preset threshold When , it means that the GPS signal is lost. The lost point means that the plane distance formula under the geodetic coordinate system is used to calculate the straight-line distance between the two points. The calculation formula is:

[0109]

[0110] In the formula, It is the position difference between two consecutive ADS-B records, indicating the distance between the two points; and Represent the longitude coordinates in the first ADS-B record and the longitude coordinates in the second ADS-B record respectively; and Represents the latitude coordinate in the first ADS-B record and the latitude coordinate in the second ADS-B record, respectively.

[0111] In this embodiment, the time points of GPS signal loss and recovery are identified in combination with QAR data, including the following steps:

[0112] Get the speed, altitude and attitude information of QAR data;

[0113] Based on the QAR data, if the parameters of speed, altitude and attitude information change abnormally, the GPS signal is lost, and the position loss point is marked and recorded; when the flight parameters in the QAR data return to normal, combined with the smooth trajectory changes in the ADS-B data, the time point of GPS signal recovery is confirmed, and the position recovery point is marked and recorded;

[0114] By comparing and analyzing the ADS-B data, the exact time points of GPS signal loss and recovery are calibrated. The timestamps in the QAR data are aligned with the start and end times of the interference period to accurately calibrate the time points of loss and recovery.

[0115] For example, suppose that a flight A is interfered with on route B. When performing GPS interference detection, data is first acquired. The airline provides the ADS-B data, QAR data and flight trajectory data of flight A and route B. These data can monitor the GPS status during the flight in real time; then time synchronization is performed and GPS signal loss judgment is performed. The ADS-B data, QAR data and flight trajectory data are aligned through timestamps. When judging the loss of GPS signal, if it is found that the displacement in the ADS-B data exceeds the preset threshold (for example, 200 meters) within a certain period of time, and there is a large difference between the speed in the QAR data and the speed in the ADS-B data (greater than 10 knots), it is judged that the GPS signal is lost based on these characteristics; then GPS recovery judgment is performed. If the trajectory in the ADS-B data gradually returns to normal, and the flight parameters in the QAR data (such as speed and altitude) also return to stability. The system finally confirms that the GPS signal has been restored and marks the recovery point. Through the above analysis, the system determines the GPS interference period of flight A on route B, and records the start and end time of the interference, forming the boundary of the interference period.

[0116] This embodiment accurately determines the time points of loss and recovery of aircraft GPS signals based on ADS-B data, QAR data, and flight trajectory data, and combines the data of the operator's base station to provide an important basis for locating the interference source. Through the precise identification of the interference period boundary and the GPS signal loss and recovery points, it can provide real-time interference warnings to aviation management departments to ensure the flight safety of aircraft.

[0117] Step S30: Determine the aircraft interference area based on the aircraft's flight trajectory data and the position loss points and position recovery points during the interference period.

[0118] In this step, see Figure 3 As shown in the figure, determining the area where the aircraft is interfered with includes the following steps:

[0119] Step S301: Determine the latitude and longitude, timestamp, altitude, speed and heading information of the aircraft during the interference period based on the acquired flight trajectory data.

[0120] By determining the latitude and longitude, timestamp, altitude, speed and heading information of the aircraft during the interference period, the flight status of the aircraft during the interference period can be analyzed, and the specific location of the interference period and its corresponding time can be determined.

[0121] For example, the flight trajectory data of aircraft A on route B includes:

[0122] Longitude: 120.1234°, Latitude: 30.5678°;

[0123] Timestamp: 2025-01-01 10:00:00;

[0124] Altitude: 10,000 feet

[0125] Speed: 450 knots

[0126] Heading: 270° (flying west).

[0127] The above data can be used to determine the flight characteristics of the aircraft during the interference period.

[0128] Step S302: After the aircraft data is synchronized, the time point and position loss point (GPS failure point) of the aircraft GPS signal loss during the interference period are determined by comparing the ADS-B and QAR data, and the time point and position recovery point (GPS recovery point) of the GPS signal recovery are determined.

[0129] Among them, by comparing and analyzing ADS-B data and QAR data, it is possible to identify the time point and position loss point of GPS signal loss (i.e. GPS failure point), as well as the time point and position recovery point of GPS signal recovery (i.e. GPS recovery point). The above information is determined by the following steps:

[0130] (1) GPS signal loss point: If there is a sudden jump in position or a large position change (for example, greater than 500 meters) in the ADS-B data, or an abnormal change in speed recorded in the QAR data (for example, a speed difference greater than 20 knots), GPS signal loss occurs.

[0131] (2) GPS signal recovery point: After a certain period of time, the trajectory in the ADS-B data becomes smooth again and the flight parameters (such as speed and altitude) in the QAR data return to normal, which is the moment when the GPS signal is restored.

[0132] For example: Through analysis, the GPS signal of aircraft A was lost at 2025-01-01 10:05:00, and the coordinates of the lost point are (120.1300°, 30.5800°). At 2025-01-01 10:20:00, the GPS signal was restored, and the coordinates of the restored point are (120.1400°, 30.5900°)

[0133] Step S303, determine the flight segment of the aircraft based on the geometry of the route and the position loss points and position recovery points during the interference period, determine the starting point and end point of the interference area on the route based on the route and the start and end positions of the interference period, and the boundary of the interference area is formed by the position loss point (track point at the time of GPS loss) and the position recovery point (track point at the time of GPS recovery).

[0134] Among them, when determining the boundary of the interference area based on the geometry of the route and the information of the GPS loss point and recovery point, the specific steps are as follows:

[0135] (1) Based on the shape of route B, the starting point (GPS signal loss point) and the ending point (GPS signal recovery point) of the interference period are determined as the boundaries of the interference area.

[0136] (2) The boundary of the route segment is calculated through spline curve fitting to ensure that the overlapping part of the route and the interference area can be accurately reflected.

[0137] For example, the starting point of the interference area is the lost point (120.1300°, 30.5800°), and the ending point is the recovery point (120.1400°, 30.5900°). According to the geometry of route B, the spline curve is used to fit the specific path of the flight segment, and the overlap between the path and the interference area is calculated.

[0138] Step S304: determine the interfered area of ​​the aircraft by determining the spatial overlap between the interfered area and the actual flight trajectory, and generate an interfered area report, wherein the interfered area report includes:

[0139] The start and end points of the interference area: including the GPS signal loss point and recovery point during the interference period;

[0140] Overlapping part of the route and the interference area: Indicates the specific location where the route and the interference area overlap;

[0141] The geometry and extent of the interference area: It is marked by polygonal or rectangular areas to give the spatial distribution of the interference area.

[0142] For example: Based on the fitting results of the flight segment and the start and end points of the interference area, a rectangular area is generated to mark the interference area, the overlap between the interference area and the aircraft route is calculated, and an interference area report is output, which includes:

[0143] (1) The starting and ending points of the interference area: GPS loss point (120.1300°, 30.5800°) and GPS recovery point (120.1400°, 30.5900°).

[0144] (2) Overlapping portion of the route and the interference area: Indicate the specific location where the route and the interference area overlap.

[0145] (3) Geometry and extent of the interference area: rectangular area (e.g., 500 m in length and 200 m in width).

[0146] Among them, the aircraft route is composed of multiple track segments, including the track segment from the starting point of the segment to the lost point, the track segment from the lost point to the re-gained point, and the track segment from the re-gained point to the end point of the segment. Each track segment is fitted with a spline curve through the track points of the aircraft to obtain the accurate boundary of the interference area, and the longitude and latitude of the lost point and the re-gained point during the interference period, as well as the result of route fitting, are used to calculate the spatial range of the interfered area; among them, the boundary of the interfered area of ​​the straight segment is calculated by the longitude and latitude of the starting and ending points of the segment; the boundary of the interfered area of ​​the curved path is judged according to the route equation of the spline curve fitting and the boundary points within a set distance on both sides of the spline curve.

[0147] Step S40: Based on the distribution topology information of the base station and the determined interfered area, collect the interference signal data received by the operator base station in the area, and match the interference signal data, ADS-B data, QAR data and flight trajectory data in the time dimension to determine the time characteristics of the interference signal.

[0148] In this step, the distribution topology information of the base station includes the latitude and longitude coordinates of the base station location and the signal coverage range. The interference area is predicted and drawn based on the signal coverage range of the base station. The interference area is the overlapping part of the areas covered by multiple base stations; see Figure 4 As shown, when predicting the interference area through the signal coverage of the base station, the following steps are included:

[0149] Step S401: Obtain the boundary of the base station interference area according to the latitude and longitude coordinates of the base station location and the signal attenuation model.

[0150] Among them, when the boundary of the base station interference area is obtained according to the latitude and longitude coordinates of the base station location and the signal attenuation model, the calculation of the base station interference area is based on the signal attenuation model of the base station. The attenuation of the signal strength at a set distance is calculated through the transmission power and signal attenuation factor of the interference source, and the range of the interference area is estimated. Among them, the distance when the signal strength attenuates to the threshold is the radius of the base station interference area, and the calculation formula is:

[0151]

[0152] In the formula, is the distance when the signal strength decays to the threshold, i.e., the radius of the base station interference area; is the transmission power of the interference source; is the path loss factor, which indicates the degree of loss during signal propagation.

[0153] Step S402: within the determined interference area of ​​the aircraft and the boundary of the interference area of ​​the base station, collect interference signal data through the base station, including the strength, frequency and time stamp of the interference signal;

[0154] Step S403: aligning the interference signal data collected by the base station, the ADS-B data, the QAR data and the flight trajectory data of the aircraft in the time dimension;

[0155] Step S404: Once the data is aligned in the time dimension, the time characteristics of the interference signal are analyzed according to the flight trajectory and the interference signal received by the base station, and the duration of the interference signal, the rate of change of the interference signal strength and the fluctuation characteristics of the interference signal are picked up;

[0156] Step S405: combining the flight trajectory data with the time characteristics of the interference signal data, finding the overlap between the flight and the interference area, and analyzing whether the flight path crosses the interference area;

[0157] Step S406: By statistically analyzing the time characteristics of multiple interference events, extracting the pattern of the interference signal, and determining the occurrence frequency, duration distribution and intensity change trend of the interference signal.

[0158] For example, base station A is located at (120.1350°, 30.5850°), and according to the transmission power and signal attenuation factor, the interference area radius of base station A is calculated to be 1 km. The collected interference signal data shows that the interference signal has a strong fluctuation from 2025-01-01 10:05:00 to 2025-01-01 10:20:00, and the intensity of the interference signal continues to change during this time period.

[0159] Assume that GPS interference occurs between 10:05:00 and 10:20:00 on 2025-01-01 when flight A is flying on route B, and the flight path of flight A crosses the interference area of ​​the base station. After the interference signal data of the base station is aligned with the flight trajectory data of the flight, the start and end points of the interference period can be accurately identified, and the interference area can be mapped. By analyzing multiple interference events and extracting the characteristics of the interference signal, airlines and air traffic control departments can be helped to timely predict and locate GPS interference sources, thereby improving flight safety.

[0160] Step S50: Analyze the signal receiving power and gain difference of the interference signal data received by the base station during the interference period according to the time characteristics of the interference signal, and determine the vector direction of the interference source signal.

[0161] In this step, see Figure 5 As shown, determining the vector direction of the interference source signal includes the following steps:

[0162] Step S501: collect the interference signal power received by the base station during the flight of the aircraft, including timestamp, received signal strength and gain data, and filter out the time period when the interference signal strength exceeds a preset threshold.

[0163] Among them, during the flight of the route, the power information of the interference signal received by the base station includes timestamp, signal strength and gain data. Each base station is equipped with multiple receiving antennas, each with different antenna gains. By monitoring the interference signal received by the base station, the following data is recorded:

[0164] Timestamp: The exact time the signal was received.

[0165] Signal strength: In dBm, it indicates the received signal power.

[0166] Gain: The gain of the base station receiving antenna, which indicates the antenna's ability to enhance signals.

[0167] Exemplarily, the data of the interference signal received by the base station B1 is:

[0168] Timestamp: 2025-01-01 10:10:00;

[0169] Signal strength: -90 dBm;

[0170] Gain: 12 dB;

[0171] The data of the interference signal received by base station B2 is:

[0172] Timestamp: 2025-01-01 10:10:00;

[0173] Signal strength: -85 dBm;

[0174] Gain: 10 dB.

[0175] Among them, according to the preset interference signal strength threshold, the time period when the interference signal strength exceeds the threshold is screened out. During these time periods, the signal strength received by the base station is significantly higher than the background noise, so it can be determined as an interference signal. For example, assuming that the set threshold is -100 dBm, the signal strengths received by base stations B1 and B2 (-90 dBm and -85 dBm) both exceed the threshold, so the signals of these two base stations are considered interference signals.

[0176] Step S502: Calculate the change rate of the interference signal according to the received interference signal strength data, and identify the sudden interference of the signal.

[0177] The signal change rate is calculated by analyzing the change of interference signal strength over time. Sudden interference usually manifests itself as a sharp change in signal strength in a short period of time. The change rate of signal strength can be calculated by the following formula:

[0178]

[0179] In the formula, is the change in signal strength, is the time interval between signal strength changes.

[0180] For example, at 2025-01-01 10:10:00, the signal strength of base station B1 is -90 dBm; at 10:11:00, the signal strength of base station B1 is -70 dBm. The signal strength change rate is:

[0181]

[0182] This rate of change indicates a rapid increase in signal strength, which is a sudden interference.

[0183] Step S503: According to the known receiving antenna gain of the base station, the direction of the interference source is calculated by the gain difference, and according to the signal strength and the gain difference, the distance of the interference source relative to the base station is obtained, and the direction of the interference source is further estimated;

[0184] When multiple base stations receive the same interference signal, triangulation is used to measure the difference in the strength of the interference signals received by different base stations. Based on the signal strength received by each base station, the distance from the interference source to each base station is estimated, and the least squares method is used to obtain the position of the interference source, the direction of the interference source is estimated, and the vector direction of the interference source signal is obtained in combination with the estimated direction of the interference source.

[0185] When estimating the direction of the interference source, the distance between the interference source and the base station is calculated by the signal strength, where the received signal strength The calculation formula is:

[0186]

[0187] In the formula, is the received signal strength, unit: dBm; The transmission power of the interference source, in dBm, is the power of the signal transmitting end when the interference source transmits the signal; is the path loss index, the product of the path loss index Controls the rate of signal attenuation, that is, the amplitude of signal strength attenuation per unit distance increase. In a free space environment, , which indicates the degree of signal attenuation as the distance increases; It is a constant of the product of the path loss exponent, which indicates the attenuation of the signal strength for each unit distance increase when the signal propagates in space, that is, the relationship between the amplitude of the path loss and the logarithmic change of the propagation distance. The path loss exponent The rate at which the signal is attenuated is affected. The more complex the environment is and the more obstacles there are, The larger the value of ; is the distance from the interference source to the receiving base station, in meters; It is the distance The logarithm of reflects the characteristic that the signal strength decreases with the increase of distance, and the signal attenuation follows the logarithmic law;

[0188] When the transmission power is known , path loss index and the distance from the interference source to the receiving base station When the received signal strength can be calculated Similarly, if the received signal strength is known , Transmit power and path loss exponent , the distance from the interference source to the receiving base station can also be calculated , the calculation formula is:

[0189]

[0190] The above formula can be used to infer the location of the interference source based on the signal strength, or to estimate the characteristics of signal propagation.

[0191] Step S60: Calculate the signal strength of the interference source by measuring the signal strength of the interference signal in different antenna sectors of each base station during the interference period, and calculate the precise position of the interference source in three-dimensional space through the interference signal vector directions of multiple base stations and the signal strength of the interference source.

[0192] In this step, when the back propagation model is used to infer the spatial position of the interference source, the geometric relationship between the interference source and the base station and the aircraft is calculated in the spatial coordinate system, wherein the calculation formula for the distance from the base station to the interference source is:

[0193]

[0194] In the formula, For base station Distance to the interference source; ( , , ) is the base station The spatial coordinates of , , ) is the spatial coordinate of the interference source.

[0195] When constructing a three-dimensional model of the area where the interference source is located, a three-dimensional spherical model of the area is constructed by defining the radius of the area affected by the interference source. The radius calculation formula of the area affected by the interference source is:

[0196]

[0197] In the formula, is the radius of the interference source impact area, that is, the radius of the base station interference area; is the transmission power of the interference source; is the path loss factor, which indicates the degree of loss during signal propagation.

[0198] The present invention can accurately locate the interference source and combine the real-time flight data of the aircraft to give early warning before the interference source has an impact, effectively reducing the flight safety risks caused by the loss of GPS signals. Through the real-time data collection of base station signals, the position change of the interference source can be dynamically monitored, and the position of the interference source in three-dimensional space can be accurately calculated by analyzing the interference signals of multiple base stations. This real-time monitoring and dynamic tracking capability makes the positioning of the interference source no longer static, but dynamically adjusted as the interference source moves, ensuring the high accuracy of the interference source positioning.

[0199] Step S70: Based on the precise location of the interference source, combined with the spatial information of the GPS position loss point and the position recovery point during the flight of the aircraft, and the signal data of multiple base stations, a three-dimensional spatial model of the area where the interference source is located is constructed to simulate the impact area of ​​the interference source and generate interference source warning information.

[0200] In this step, when constructing the three-dimensional spatial model of the interference source, the spatial position of the interference source is calculated by combining the signal strength data and aircraft position data received by the base station. Based on the calculated interference source coordinates and combined with the propagation model of the interference signal, the positioning accuracy of the interference source is corrected. According to the spatial coordinates, a three-dimensional model of the area where the interference source is located is constructed, which indicates the position of the interference source in three-dimensional space and the scope of influence.

[0201] For example, assume that aircraft A is flying on route B and loses GPS signal between 10:00 and 10:30 on January 1, 2025. Base stations B1 and B2 both receive strong interference signals, and the signal strength changes dramatically in a short period of time. By analyzing the signal data received by the base stations, the present invention calculates the direction of the interference source and uses triangulation to locate the position of the interference source.

[0202] Furthermore, based on the location information of the interference source, the present invention combines the flight trajectory data of the aircraft to generate a three-dimensional spatial model of the interference source, simulates the influence range of the interference source, and adds the influence radius of the interference source to the model. Finally, by integrating various information, early warning information of the interference source is generated to help airlines and air traffic control departments to warn and respond to GPS interference in real time to ensure flight safety.

[0203] The present invention can calculate the precise location of the interference source through the analysis of the interference signal data received by the base station, the flight trajectory of the aircraft, and the position loss point and the re-gain point, and further construct a three-dimensional space model, and use the signal strength difference between multiple base stations to perform accurate calculations through a three-dimensional positioning algorithm, which significantly improves the accuracy of interference source positioning compared to the traditional single base station positioning method. By performing multi-dimensional fusion analysis of ADS-B data, QAR data, flight trajectory data and interference signal data received by the base station, the fault tolerance of the system under various complex interference conditions is improved. When the signal quality of a certain base station is poor, the system can still locate and track the interference source through other base station data, ensuring the stability and robustness of the system under different conditions.

[0204] The present invention can generate detailed interference source warning information based on the positioning results of the interference source, and send alarms to aviation management departments, aircraft and other relevant parties in a timely manner. By obtaining information such as the location of the interference source, signal strength and impact range in advance, aviation management personnel can formulate countermeasures to reduce the impact of interference on navigation. The early warning mechanism can be deployed in advance before the interference source causes interference, thereby providing aircraft with sufficient emergency response time. By constructing a three-dimensional spatial model of the area where the interference source is located, it is possible to accurately simulate the propagation law of the interference signal in different environments and predict its impact range. This is of great significance for aircraft route planning, further control of interference sources, and aviation safety management.

[0205] It should be noted that the above figures are only schematic illustrations of the processes included in the method according to an exemplary embodiment of the present invention, and are not intended to be limiting. It is easy to understand that the processes shown in the above figures do not indicate or limit the time sequence of these processes. In addition, it is also easy to understand that these processes can be performed synchronously or asynchronously, for example, in multiple modules.

[0206] It should be understood that, although described in a certain order, these steps are not necessarily performed in sequence in the above order. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be performed in other orders. Moreover, a part of the steps of the present embodiment may include a plurality of steps or a plurality of stages, and these steps or stages are not necessarily performed at the same time, but can be performed at different times, and the execution order of these steps or stages is not necessarily performed in sequence, but can be performed in turn or alternately with at least a part of the steps or stages in other steps or other steps.

[0207] In a second aspect of the embodiments of the present invention, the present invention further provides a GPS interference warning and positioning system based on an operator base station, comprising:

[0208] Data acquisition module, used to obtain ADS-B data, QAR data and flight trajectory data of aircraft during interference periods;

[0209] The interference signal detection module is used to determine the GPS position loss and position recovery points of the aircraft during the interference period based on the aircraft's flight trajectory and ADS-B data, and identify the time points of GPS signal loss and recovery in combination with QAR data;

[0210] The regional positioning module is used to determine the interference area of ​​the aircraft based on the flight trajectory data of the aircraft and the position loss points and position recovery points during the interference period;

[0211] The time feature matching module is used to collect interference signal data received by the operator base stations in the area based on the distribution topology information of the base stations and the determined interference area, and match the interference signal data, ADS-B data, QAR data and flight trajectory data in the time dimension to determine the time characteristics of the interference signal;

[0212] The interference source positioning module is used to calculate the signal strength of the interference source by measuring the signal strength of the interference signal in different antenna sectors of each base station during the interference period, and calculate the precise position of the interference source in three-dimensional space through the interference signal vector direction of multiple base stations and the signal strength of the interference source;

[0213] The three-dimensional spatial modeling module is used to construct a three-dimensional spatial model of the area where the interference source is located based on the precise location of the interference source, combined with the spatial information of the GPS position loss point and position recovery point during the aircraft flight, and the signal data of multiple base stations, simulate the impact area of ​​the interference source, and generate interference source warning information.

[0214] Through the above detailed steps, the GPS interference warning and positioning system based on the operator base station of the present invention is used to execute the steps of the GPS interference warning and positioning method based on the operator base station in the above embodiment, which will not be repeated here.

[0215] In summary, the GPS interference warning and positioning method and system based on the operator base station of the present invention not only effectively improves the accuracy of interference source positioning, but also provides a strong guarantee for the safe flight of aircraft. Through the comprehensive application of high-precision positioning, multi-source data fusion, three-dimensional space modeling and interference source warning technologies, it can significantly reduce aviation safety accidents caused by GPS interference and improve the accuracy and response speed of aviation management.

[0216] The above are exemplary embodiments disclosed in the present invention, but it should be noted that various changes and modifications may be made without departing from the scope disclosed in the embodiments of the present invention as defined in the claims. The functions, steps and / or actions of the method claims according to the disclosed embodiments described herein do not need to be performed in any particular order. In addition, although the elements disclosed in the embodiments of the present invention may be described or required in individual form, they may also be understood as multiple unless explicitly limited to the singular.

[0217] It should be understood that, as used herein, the singular form "a" or "an" is intended to include the plural form as well, unless the context clearly supports an exception. It should also be understood that, as used herein, "and / or" refers to any and all possible combinations of one or more of the items listed in association. The serial numbers of the embodiments disclosed in the above embodiments of the present invention are for description only and do not represent the advantages and disadvantages of the embodiments.

[0218] A person skilled in the art should understand that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of the disclosure of the embodiments of the present invention (including the claims) is limited to these examples; under the concept of the embodiments of the present invention, the technical features in the above embodiments or different embodiments can also be combined, and there are many other changes in different aspects of the above embodiments of the present invention, which are not provided in detail for the sake of simplicity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present invention should be included in the protection scope of the embodiments of the present invention.

Claims

1. A GPS interference early warning and positioning method based on an operator base station, characterized in that: The method comprises the following steps: Obtain the aircraft's ADS-B data, QAR data and flight trajectory data during the interference period; Based on the aircraft's flight trajectory and ADS-B data, determine the points where the aircraft's GPS position was lost and regained during the interference period, and combine it with QAR data to identify the time points when the GPS signal was lost and restored; Determine the interference area of ​​the aircraft based on the flight trajectory data of the aircraft and the position loss points and position recovery points during the interference period; Based on the distribution topology information of base stations and the determined interference area, collect the interference signal data received by the operator base stations in the area, and match the interference signal data, ADS-B data, QAR data and flight trajectory data in the time dimension to determine the time characteristics of the interference signal; Analyze the signal receiving power and gain difference of the interference signal data received by the base station during the interference period according to the time characteristics of the interference signal, and determine the vector direction of the interference source signal; By measuring the signal strength of the interference signal in different antenna sectors of each base station during the interference period, the signal strength of the interference source is calculated, and the precise position of the interference source in three-dimensional space is calculated through the interference signal vector direction of multiple base stations and the signal strength of the interference source; Based on the precise location of the interference source, combined with the spatial information of the GPS position loss points and position recovery points during the aircraft flight, as well as the signal data of multiple base stations, a three-dimensional spatial model of the area where the interference source is located is constructed, the impact area of ​​the interference source is simulated, and interference source warning information is generated.

2. The GPS interference early warning and positioning method based on the operator base station according to claim 1, characterized in that: Based on the aircraft's flight trajectory and ADS-B data, determine the aircraft's GPS position loss point and position recovery point during the interference period, including the following steps: The acquired aircraft ADS-B data, QAR data and flight trajectory data are synchronized in time and mapped into a unified time sequence through timestamp alignment; By comparing the GPS coordinates in the ADS-B data with the heading and speed information in the QAR data, it is determined whether the GPS signal is lost; If the jump amplitude between multiple consecutive position points in the ADS-B data exceeds the preset jump threshold, the position jumps and GPS signal loss occurs; If the speed change recorded in the QAR data differs from the speed reported by the ADS-B by more than the preset speed difference threshold, the speed is abnormal and GPS signal loss has occurred; In ADS-B data, when the GPS signal is lost for a period of time and then restored, and the restored trajectory is consistent with the route, and the speed in the QAR data matches the restored GPS data, the GPS position is considered to be restored, and the position loss point and position recovery point are identified and recorded to form the boundary of the interference period.

3. The GPS interference early warning and positioning method based on the operator base station as claimed in claim 2, characterized in that: When judging whether the GPS signal is lost, if the displacement between two consecutive ADS-B records is , and the time interval between two consecutive ADS-B records is ,when Greater than the preset threshold When the GPS signal is lost, the lost point is identified by using the plane distance formula in the geodetic coordinate system to calculate the straight-line distance between the two points. The calculation formula is: In the formula, It is the position difference between two consecutive ADS-B records, indicating the distance between the two points; and Represent the longitude coordinates in the first ADS-B record and the longitude coordinates in the second ADS-B record respectively; and Represents the latitude coordinate in the first ADS-B record and the latitude coordinate in the second ADS-B record, respectively.

4. The GPS interference early warning and positioning method based on the operator base station as claimed in claim 3 is characterized in that: Combined with QAR data, identifying the time points when the GPS signal was lost and restored includes the following steps: Get the speed, altitude and attitude information of QAR data; Based on the QAR data, if the parameters of speed, altitude and attitude information change abnormally, the GPS signal is lost, and the position loss point is marked and recorded; when the flight parameters in the QAR data return to normal, combined with the smooth trajectory changes in the ADS-B data, the time point of GPS signal recovery is confirmed, and the position recovery point is marked and recorded; By comparing and analyzing the ADS-B data, the exact time points of GPS signal loss and recovery are calibrated. The timestamps in the QAR data are aligned with the start and end times of the interference period to accurately calibrate the time points of loss and recovery.

5. The GPS interference early warning and positioning method based on the operator base station as claimed in claim 4, characterized in that: Determine the area where the aircraft is disturbed, including the following steps: Determine the latitude and longitude, timestamp, altitude, speed and heading information of the aircraft during the interference period based on the acquired flight trajectory data; After the aircraft data is synchronized, the time point and position loss point of the aircraft GPS signal during the interference period are determined by comparing the ADS-B and QAR data, and the time point and position recovery point of the GPS signal are determined; Determine the flight segment of the aircraft based on the geometry of the route and the position loss points and position recovery points during the interference period, determine the starting and ending points of the interference area on the route based on the route and the start and end positions of the interference period, and the position loss points and position recovery points constitute the boundaries of the interference area; The interference area of ​​the aircraft is determined by judging the spatial overlap between the interference area and the actual flight trajectory, and an interference area report is generated, where the interference area report includes: The start and end points of the interference area: including the GPS signal loss point and recovery point during the interference period; Overlapping part of the route and the interference area: Indicates the specific location where the route and the interference area overlap; The geometry and extent of the interference area: It is marked by polygonal or rectangular areas to give the spatial distribution of the interference area.

6. The GPS interference early warning and positioning method based on the operator base station as claimed in claim 5, characterized in that: The aircraft route consists of multiple track segments, including the track segment from the starting point of the segment to the lost point, the track segment from the lost point to the re-gained point, and the track segment from the re-gained point to the end point of the segment. Each track segment is fitted with a spline curve through the track points of the aircraft to obtain the accurate boundary of the interference area, and the longitude and latitude of the lost point and the re-gained point during the interference period, as well as the result of route fitting, are used to calculate the spatial range of the interfered area; among them, the boundary of the interfered area of ​​the straight segment is calculated by the longitude and latitude of the starting and ending points of the segment; the boundary of the interfered area of ​​the curved path is determined based on the route equation of the spline curve fitting and the boundary points within a set distance on both sides of the spline curve.

7. The GPS interference early warning and positioning method based on the operator base station according to claim 6, characterized in that: The distribution topology information of the base station includes the latitude and longitude coordinates of the base station location and the signal coverage range. The interference area is predicted and drawn through the signal coverage range of the base station. The interference area is the overlapping part of the areas covered by multiple base stations. When the interference area is predicted through the signal coverage range of the base station, the following steps are included: According to the latitude and longitude coordinates of the base station location and the signal attenuation model, the boundary of the base station interference area is obtained; Collect interference signal data through the base station within the determined interference area of ​​the aircraft and the boundary of the interference area of ​​the base station, including the strength, frequency and time stamp of the interference signal; Align the interference signal data collected by the base station, the ADS-B data of the aircraft, the QAR data and the flight trajectory data in the time dimension; Once the data is aligned in the time dimension, the time characteristics of the interference signal are analyzed according to the flight trajectory and the interference signal received by the base station, picking up the duration of the interference signal, the rate of change of the interference signal strength and the fluctuation characteristics of the interference signal; Combine the flight trajectory data with the time characteristics of the interference signal data to find the overlap between the flight and the interference area, and analyze whether the flight path crosses the interference area; By statistically analyzing the temporal characteristics of multiple interference events, the patterns of interference signals are extracted, and the occurrence frequency, duration distribution and intensity variation trend of interference signals are determined.

8. The GPS interference early warning and positioning method based on the operator base station as claimed in claim 7, characterized in that: When the boundary of the base station interference area is obtained according to the latitude and longitude coordinates of the base station location and the signal attenuation model, the calculation of the base station interference area is based on the signal attenuation model of the base station. The attenuation of the signal strength at the set distance is calculated through the transmission power and signal attenuation factor of the interference source, and the range of the interference area is estimated. Among them, the distance when the signal strength attenuates to the threshold is the radius of the base station interference area. The calculation formula is: In the formula, is the distance when the signal strength decays to the threshold, i.e., the radius of the base station interference area; is the transmission power of the interference source; is the path loss factor, which indicates the degree of loss during signal propagation.

9. The GPS interference early warning and positioning method based on the operator base station according to claim 1, characterized in that: Determining the vector direction of the interference source signal includes the following steps: Collect the interference signal power received by the base station during the flight of the aircraft, including timestamp, received signal strength and gain data, and filter out the time period when the interference signal strength exceeds the preset threshold; According to the received interference signal strength data, the change rate of the interference signal is calculated to identify the sudden interference of the signal; Based on the known receiving antenna gain of the base station, the direction of the interference source is calculated through the gain difference, and the distance of the interference source relative to the base station is obtained based on the signal strength and gain difference, and the direction of the interference source is further estimated; When multiple base stations receive the same interference signal, triangulation is used to measure the difference in the strength of the interference signals received by different base stations. Based on the signal strength received by each base station, the distance from the interference source to each base station is estimated, the position of the interference source is obtained by the least square method, the direction of the interference source is estimated, and the vector direction of the interference source signal is obtained in combination with the estimated direction of the interference source; When estimating the direction of the interference source, the distance between the interference source and the base station is calculated by the signal strength, where the received signal strength The calculation formula is: In the formula, is the received signal strength, unit: dBm; The transmission power of the interference source, in dBm, is the power of the signal transmitting end when the interference source transmits the signal; is the path loss index, the product of the path loss index Controls the rate of signal attenuation, that is, the magnitude of signal strength attenuation per unit distance increase; It is the distance The logarithm of reflects the characteristic that the signal strength decreases with the increase of distance, and the signal attenuation follows the logarithmic law; Calculate the distance from the interference source to the receiving base station , the calculation formula is: The above formula can be used to infer the location of the interference source based on the signal strength, or to estimate the characteristics of signal propagation.

10. A GPS interference warning and positioning system based on an operator base station, characterized in that: The system is used to execute the GPS interference early warning and positioning method based on the operator base station according to any one of claims 1 to 9, comprising: Data acquisition module, used to obtain ADS-B data, QAR data and flight trajectory data of aircraft during interference periods; The interference signal detection module is used to determine the GPS position loss and position recovery points of the aircraft during the interference period based on the aircraft's flight trajectory and ADS-B data, and identify the time points of GPS signal loss and recovery in combination with QAR data; The regional positioning module is used to determine the interference area of ​​the aircraft based on the flight trajectory data of the aircraft and the position loss points and position recovery points during the interference period; The time feature matching module is used to collect interference signal data received by the operator base stations in the area based on the distribution topology information of the base stations and the determined interference area, and match the interference signal data, ADS-B data, QAR data and flight trajectory data in the time dimension to determine the time characteristics of the interference signal; The interference source positioning module is used to calculate the signal strength of the interference source by measuring the signal strength of the interference signal in different antenna sectors of each base station during the interference period, and calculate the precise position of the interference source in three-dimensional space through the interference signal vector direction of multiple base stations and the signal strength of the interference source; The three-dimensional spatial modeling module is used to construct a three-dimensional spatial model of the area where the interference source is located based on the precise location of the interference source, combined with the spatial information of the GPS position loss point and position recovery point during the aircraft flight, and the signal data of multiple base stations, simulate the impact area of ​​the interference source, and generate interference source warning information.

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