Low-altitude flight target alarm system and method based on Beidou satellite navigation system

Abstract

The embodiment of the invention provides a low-altitude flight target alarm system and method based on a Beidou satellite navigation system, and the method comprises the steps: obtaining a high-precision three-dimensional city map which comprises a preset no-fly zone, obstacle space information and meteorological information; determining a signal acquisition strategy in the preset no-fly zone according to the obstacle space information and the weather information, wherein the signal acquisition strategy comprises acquisition of a multi-band signal of a Beidou satellite and / or acquisition of a visual signal; determining position information of the low-altitude flight target according to a precision signal and / or a visual signal corresponding to the multi-band signal; and obtaining a layered alarm scheme corresponding to the preset no-fly zone, and executing alarm based on the position information of the low-altitude flight target and the layered alarm scheme. According to the invention, a low-altitude flying target can be detected and alarmed in a special extreme environment.

Description

Technical Field

[0001] The present invention relates to the technical field of low-altitude flight warning, and particularly to a low-altitude flight target warning system and method based on the Beidou satellite navigation system. Background Art

[0002] When low-altitude flight targets (such as unmanned aerial vehicles) move in the low-altitude airspace (usually referring to the height from the ground to 1000 meters), there are many blind spots in traditional monitoring means. When using radar detection, low-altitude targets are easily blocked by ground clutter (buildings, mountains, etc.), and there are blind spots in radar detection. Small unmanned aerial vehicles (RCS < 0.01m 2 ) have weak reflected signals, and it is difficult for traditional radars to stably track them. Visible light / infrared cameras for optical / infrared monitoring are greatly affected by weather (fog, rain, night darkness), and cannot provide accurate position information. When detecting based on ADS-B, most light unmanned aerial vehicles or illegal aircraft are not equipped with ADS-B transmitters and cannot be monitored by the air traffic control system. In addition, malicious targets may use GPS / Beidou signal interference or spoofing means, resulting in positioning failure. Low-altitude flight targets (such as unmanned aerial vehicles) are easily affected by signal occlusion, etc. in complex urban environments, resulting in a decrease in the positioning accuracy of the Beidou satellite navigation system and making it difficult to achieve real-time and reliable warning. Summary of the Invention

[0003] The purpose of the embodiments of the present invention is to provide a low-altitude flight target warning system and method based on the Beidou satellite navigation system, and the low-altitude flight target warning system and method based on the Beidou satellite navigation system can detect and warn low-altitude flight targets in special extreme environments.

[0004] To achieve the above purpose, the embodiments of the present invention provide a low-altitude flight target warning method based on the Beidou satellite navigation system, which is characterized in that the low-altitude flight target warning method based on the Beidou satellite navigation system includes: obtaining a high-precision three-dimensional city map, where the three-dimensional city map includes a preset no-fly zone, obstacle spatial information, and meteorological information; determining a signal acquisition strategy within the preset no-fly zone according to the obstacle spatial information and the meteorological information, where the signal acquisition strategy includes acquiring multi-band signals of Beidou satellites and / or acquiring visual signals; determining the position information of the low-altitude flight target according to the accuracy signals corresponding to the multi-band signals and / or the visual signals; and obtaining a hierarchical warning scheme corresponding to the preset no-fly zone, and performing a warning based on the position information of the low-altitude flight target and the hierarchical warning scheme.

[0005] Preferably, determining the signal acquisition strategy within the preset no-fly zone according to the obstacle spatial information and the meteorological information includes:

[0006] When the meteorological information indicates weather with visibility lower than a preset visibility threshold and there is no obstacle occlusion in the obstacle spatial information, the signal acquisition strategy includes acquiring multi-band signals of Beidou satellites and acquiring visual signals when the multi-band signals are interrupted;

[0007] When the meteorological information indicates weather with visibility higher than a preset visibility threshold and there is no obstacle occlusion in the obstacle spatial information, continuously acquire visual signals and continuously acquire multi-band signals of Beidou satellites; and

[0008] When there is obstacle occlusion in the obstacle spatial information, the signal acquisition strategy includes acquiring multi-band signals of Beidou satellites.

[0009] Preferably, determining the position information of the low-altitude flight target according to the accuracy signal corresponding to the multi-band signal and / or the visual signal includes:

[0010] Using integrated MEMS inertial navigation and visual SLAM technology to determine the first estimated position information corresponding to the visual signal; and / or

[0011] Based on differential enhancement technology, determine the accuracy signal corresponding to the multi-band signal, and based on the accuracy signal, determine the second estimated position information of the low-altitude flight target; and

[0012] Determine the position information of the low-altitude flight target according to a preset position definition relationship between the first estimated position information and the second estimated position information set in advance.

[0013] Preferably, acquiring a hierarchical warning scheme corresponding to a preset no-fly zone and executing a warning based on the position information of the low-altitude flight target and the hierarchical warning scheme includes:

[0014] The hierarchical warning scheme includes different warning level schemes corresponding to high-risk areas, low-risk areas, and temporary risk areas respectively; and

[0015] Execute a warning according to the warning level scheme.

[0016] In addition, the present invention also provides a low-altitude flight target warning system based on the Beidou satellite navigation system. The low-altitude flight target warning system based on the Beidou satellite navigation system includes:

[0017] A map acquisition unit for acquiring a high-precision three-dimensional urban map, where the three-dimensional urban map includes a preset no-fly zone, obstacle spatial information, and meteorological information;

[0018] A strategy acquisition unit, configured to determine a signal acquisition strategy within the preset no-fly zone according to the obstacle space information and meteorological information, where the signal acquisition strategy includes acquiring multi-band signals of Beidou satellites and / or acquiring visual signals;

[0019] An information determination unit, configured to determine the position information of a low-altitude flight target according to the accuracy signal corresponding to the multi-band signal and / or the visual signal; and

[0020] An alarm unit, configured to obtain a hierarchical alarm scheme corresponding to the preset no-fly zone and perform an alarm based on the position information of the low-altitude flight target and the hierarchical alarm scheme.

[0021] Preferably, the strategy acquisition unit is configured to:

[0022] When the meteorological information is weather with visibility lower than a preset visibility threshold and there is no obstacle occlusion in the obstacle space information, the signal acquisition strategy includes acquiring multi-band signals of Beidou satellites, and acquiring visual signals when the multi-band signals are interrupted;

[0023] When the meteorological information is weather with visibility higher than the preset visibility threshold and there is no obstacle occlusion in the obstacle space information, continuously acquire visual signals and continuously acquire multi-band signals of Beidou satellites; and

[0024] When there is obstacle occlusion in the obstacle space information, the signal acquisition strategy includes acquiring multi-band signals of Beidou satellites.

[0025] Preferably, the information determination unit is configured to:

[0026] Utilize integrated MEMS inertial navigation and visual SLAM technology to determine the first estimated position information corresponding to the visual signal; and / or

[0027] Determine the accuracy signal corresponding to the multi-band signal based on differential enhancement technology, and determine the second estimated position information of the low-altitude flight target based on the accuracy signal; and

[0028] Determine the position information of the low-altitude flight target according to a preset position definition relationship between the first estimated position information and the second estimated position information set in advance.

[0029] Preferably, the hierarchical alarm scheme includes different alarm level schemes corresponding to a high-risk area, a low-risk area, and a temporary risk area respectively; and

[0030] The alarm unit is configured to perform an alarm according to the alarm level scheme.

[0031] In addition, the present invention also provides a machine-readable storage medium, on which instructions are stored for causing a machine to execute the above-mentioned low-altitude flying target warning method based on the Beidou satellite navigation system.

[0032] In addition, the present invention also provides a processor for running a program, wherein when the program is run, it is used to execute: the above-mentioned low-altitude flying target warning method based on the Beidou satellite navigation system.

[0033] Through the above technical solution, the present invention combines the multi-frequency bands of Beidou-3 with visual sensing to solve the problem of continuous high-precision warning of low-altitude dynamic targets in complex environments in complex urban environments. The horizontal positioning error in urban environments is <0.5 meters (the traditional method > 5 meters), and the warning omission rate is reduced by 90%. It effectively ensures accurate positioning.

[0034] Other features and advantages of the embodiments of the present invention will be described in detail in the subsequent specific implementation part. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The drawings are used to provide a further understanding of the embodiments of the present invention, and constitute a part of the specification. Together with the following specific implementation manners, they are used to explain the embodiments of the present invention, but do not constitute a limitation to the embodiments of the present invention. In the drawings:

[0036] Figure 1 is a flowchart of a method for warning low-altitude flying targets based on the Beidou satellite navigation system according to the present invention; and

[0037] Figure 2 is a structural block diagram of a system for warning low-altitude flying targets based on the Beidou satellite navigation system according to the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0038] The following will detail the specific implementation manners of the embodiments of the present invention with reference to the drawings. It should be understood that the specific implementation manners described herein are only used to illustrate and explain the embodiments of the present invention, and are not used to limit the embodiments of the present invention.

[0039] The present invention provides a method for warning low-altitude flying targets based on the Beidou satellite navigation system.

[0040] S101, obtain a high-precision three-dimensional city map, wherein the three-dimensional city map includes a preset no-fly zone, obstacle spatial information, and meteorological information, whether it is rainy, snowy, and whether the visibility is greater than a preset threshold;

[0041] S102, determine a signal acquisition strategy within the preset no-fly zone according to the obstacle spatial information and meteorological information, wherein the signal acquisition strategy includes acquiring multi-frequency signals of Beidou satellites and / or acquiring visual signals.

[0042] The multi - band signals of the Beidou satellite of the present invention support the reception of multi - band signals such as B1C (1575.42 MHz), B2a (1176.45 MHz), and B3I (1268.52 MHz). Through multi - band joint solution (such as wide - lane combination), the ionospheric delay error (error compensation rate > 80%) and multipath effect interference are significantly reduced.

[0043] S103. Determine the position information of the low - altitude flight target according to the precision signal corresponding to the multi - band signal and / or the visual signal;

[0044] S104. Obtain the hierarchical warning scheme corresponding to the preset no - fly zone, and execute the warning based on the position information of the low - altitude flight target and the hierarchical warning scheme.

[0045] Preferably, determining the signal acquisition strategy in the preset no - fly zone according to the obstacle space information and meteorological information includes:

[0046] When the meteorological information is weather with visibility lower than the preset visibility threshold and the obstacle space information is that there is no obstacle occlusion, the signal acquisition strategy includes acquiring the multi - band signals of the Beidou satellite, and acquiring the visual signal when the multi - band signals are interrupted;

[0047] When the meteorological information is weather with visibility higher than the preset visibility threshold and the obstacle space information is that there is no obstacle occlusion, continuously acquire the visual signal and continuously acquire the multi - band signals of the Beidou satellite; and

[0048] When the obstacle space information is that there is obstacle occlusion, the signal acquisition strategy includes acquiring the multi - band signals of the Beidou satellite.

[0049] Preferably, the determining the position information of the low - altitude flight target according to the precision signal corresponding to the multi - band signal and / or the visual signal includes:

[0050] Using integrated MEMS inertial navigation and visual SLAM technologies, determine the first estimated position information corresponding to the visual signal; the visual signal is compensated by MEMS inertial navigation: a six-axis MEMS-IMU (gyro zero-bias stability < 10° / h, accelerometer noise density < 100 μg / √Hz) is used to calculate the pose of the aircraft in real time through pre-integration algorithms. Within 10 seconds of the interruption of the Beidou signal, the position drift error < 5 meters. Visual SLAM enhancement: Front-end feature matching: Based on the ORB-SLAM3 framework, use a binocular camera (global shutter, frame rate 30 Hz) to extract FAST corner features, and combine the optical flow method to achieve dynamic obstacle detection. Back-end optimization: Use factor graph optimization (Factor Graph) to fuse visual reprojection error, IMU pre-integration, and Beidou position constraints to construct a tightly coupled positioning model to ensure the robustness of SLAM in weak texture areas (such as glass curtain walls).

[0051] Based on differential enhancement technology, determine the accuracy signal corresponding to the multi-band signal, and based on the accuracy signal, determine the second estimated position information of the low-altitude flight target. Among them, differential enhancement technology, RTK (real-time kinematic): Broadcast differential correction information of Beidou observations through a ground reference station (spacing ≤ 20 km), and combine the carrier phase ambiguity fixing algorithm (LAMBDA) to achieve centimeter-level real-time positioning (horizontal accuracy 2 cm + 1 ppm). PPP (precise point positioning): Use the precise ephemeris and clock error correction parameters (such as SSR) globally broadcast by Beidou satellites, and through non-differential ambiguity resolution, achieve decimeter-level positioning in areas without base stations (update rate 1 Hz). In the present invention, anti-multipath optimization is also performed: Use an adaptive antenna array (4×4 MIMO) and signal polarization filtering technology to suppress the right-hand circular polarization (RHCP) interference signal reflected by urban buildings, and the multipath suppression ratio is increased to more than 15 dB.

[0052] Determine the position information of the low-altitude flight target according to the preset position definition relationship between the first estimated position information and the second estimated position information set in advance.

[0053] Among them, when there is only the first estimated position information or the second estimated position information, take the only information as the standard. When the first estimated position information and the second estimated position information exist at the same time and there are differences, analyze the authenticity of the corresponding position information of the two, such as comparing the gaps with the previous sampling position and the next sampling position, and obtain the position information closest to the estimated position.

[0054] Preferably, the obtaining of the hierarchical warning scheme corresponding to the preset no-fly zone and the execution of the warning based on the position information of the low-altitude flight target and the hierarchical warning scheme include:

[0055] The hierarchical warning scheme includes different warning level schemes corresponding to high-risk areas, low-risk areas, and temporary risk areas respectively; and

[0056] Execute warnings according to the warning level scheme.

[0057] In addition, Figure 2 A low-altitude flight target warning system based on the Beidou satellite navigation system provided by the present invention, the low-altitude flight target warning system based on the Beidou satellite navigation system includes:

[0058] A map acquisition unit for acquiring a high-precision three-dimensional urban map, where the three-dimensional urban map includes a preset no-fly zone, obstacle spatial information, and meteorological information;

[0059] A strategy acquisition unit for determining a signal acquisition strategy within the preset no-fly zone according to the obstacle spatial information and the meteorological information, where the signal acquisition strategy includes acquiring multi-band signals of Beidou satellites and / or acquiring visual signals;

[0060] An information determination unit for determining the position information of a low-altitude flight target according to the precision signal corresponding to the multi-band signal and / or the visual signal; and

[0061] A warning unit for acquiring a hierarchical warning scheme corresponding to the preset no-fly zone and executing warnings based on the position information of the low-altitude flight target and the hierarchical warning scheme.

[0062] Preferably, the strategy acquisition unit is used for:

[0063] When the meteorological information is weather with visibility lower than a preset visibility threshold and there is no obstacle occlusion in the obstacle spatial information, the signal acquisition strategy includes acquiring multi-band signals of Beidou satellites, and acquiring visual signals when the multi-band signals are interrupted;

[0064] When the meteorological information is weather with visibility higher than a preset visibility threshold and there is no obstacle occlusion in the obstacle spatial information, continuously acquire visual signals and continuously acquire multi-band signals of Beidou satellites; and

[0065] When there is obstacle occlusion in the obstacle spatial information, the signal acquisition strategy includes acquiring multi-band signals of Beidou satellites.

[0066] Preferably, the information determination unit is used for:

[0067] Using integrated MEMS inertial navigation and visual SLAM technology to determine the first estimated position information corresponding to the visual signal; and / or

[0068] Determine the accuracy signal corresponding to the multi-band signal based on the differential enhancement technology, and determine the second estimated position information of the low-altitude flying target based on the accuracy signal; and

[0069] Determine the position information of the low-altitude flying target according to the preset position definition relationship between the first estimated position information and the second estimated position information set in advance.

[0070] Preferably, the hierarchical warning scheme includes different warning level schemes corresponding to high-risk areas, low-risk areas, and temporary risk areas respectively; and

[0071] The warning unit is used to execute warnings according to the warning level scheme.

[0072] In addition, the present invention also provides a machine-readable storage medium, on which instructions are stored, and the instructions are used to cause a machine to execute the above-mentioned low-altitude flying target warning method based on the Beidou satellite navigation system.

[0073] In addition, the present invention also provides a processor for running a program, wherein when the program is run, it is used to execute: the above-mentioned low-altitude flying target warning method based on the Beidou satellite navigation system.

[0074] Those skilled in the art should understand that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memories, CD-ROMs, optical memories, etc.) containing computer-usable program codes.

[0075] The present application is described with reference to the flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each flow and / or block in the flowchart and / or block diagram can be implemented by computer program instructions, and the combination of the flows and / or blocks in the flowchart and / or block diagram can also be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate means for realizing the functions specified in one or more of the following processes Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks.

[0076] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a particular manner, such that the instructions stored in the computer-readable memory produce a manufacture including an instruction device that implements the functions specified in one process Figure 1 one process or multiple processes and / or blocks Figure 1 specified in one block or multiple blocks.

[0077] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operational steps are performed on the computer or other programmable device to generate a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one process Figure 1 one process or multiple processes and / or blocks Figure 1 specified in one block or multiple blocks.

[0078] In a typical configuration, a computing device includes one or more processors (CPUs), an input / output interface, a network interface, and memory.

[0079] The memory may include non-permanent memory in the form of computer-readable media, random access memory (RAM), and / or non-volatile memory such as read-only memory (ROM) or flash memory (flash RAM). The memory is an example of computer-readable media.

[0080] Computer-readable media includes both permanent and non-permanent, removable and non-removable media and can store information by any method or technology. The information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, compact disc read-only memory (CD-ROM), digital versatile discs (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory computer-readable media such as modulated data signals and carrier waves.

[0081] It should also be noted that the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, commodity or device comprising a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such process, method, commodity or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, commodity or device comprising the element.

[0082] Those skilled in the art should understand that the embodiments of the present application may be provided as a method, a system or a computer program product. Therefore, the present application may take the form of a complete hardware embodiment, a complete software embodiment or an embodiment combining software and hardware aspects. Moreover, the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0083] The above are only the embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the scope of the claims of the present application.

Claims

1. An alarm method for low-altitude flying targets based on the Beidou satellite navigation system, characterized in that, The low-altitude flight target warning method based on the Beidou satellite navigation system includes: Obtaining a high-precision three-dimensional urban map, where the three-dimensional urban map includes a preset no-fly zone, obstacle spatial information, and meteorological information; Determining a signal acquisition strategy within the preset no-fly zone according to the obstacle spatial information and the meteorological information, where the signal acquisition strategy includes acquiring multi-band signals of Beidou satellites and / or acquiring visual signals; Determining the position information of the low-altitude flight target according to the precision signal corresponding to the multi-band signal and / or the visual signal; and Obtaining a hierarchical warning scheme corresponding to the preset no-fly zone, and performing a warning based on the position information of the low-altitude flight target and the hierarchical warning scheme.

2. The low-altitude flight target warning method based on the Beidou satellite navigation system according to claim 1, wherein Determining the signal acquisition strategy within the preset no-fly zone according to the obstacle spatial information and the meteorological information includes: When the meteorological information is weather with visibility lower than a preset visibility threshold and there is no obstacle occlusion in the obstacle spatial information, the signal acquisition strategy includes acquiring multi-band signals of Beidou satellites, and acquiring visual signals when the multi-band signals are interrupted; When the meteorological information is weather with visibility higher than a preset visibility threshold and there is no obstacle occlusion in the obstacle spatial information, continuously acquire visual signals and continuously acquire multi-band signals of Beidou satellites; and When there is obstacle occlusion in the obstacle spatial information, the signal acquisition strategy includes acquiring multi-band signals of Beidou satellites.

3. The low-altitude flight target warning method based on the Beidou satellite navigation system according to claim 1, characterized in that Determining the position information of the low-altitude flight target according to the precision signal corresponding to the multi-band signal and / or the visual signal includes: Using the integrated MEMS inertial navigation and visual SLAM technology to determine the first estimated position information corresponding to the visual signal; and / or Determining the precision signal corresponding to the multi-band signal based on the differential enhancement technology, and determining the second estimated position information of the low-altitude flight target based on the precision signal; and Determining the position information of the low-altitude flight target according to a preset position definition relationship between the first estimated position information and the second estimated position information set in advance.

4. The low-altitude flight target warning method based on the Beidou satellite navigation system according to claim 1, wherein, Obtaining a hierarchical warning scheme corresponding to the preset no-fly zone, and performing a warning based on the position information of the low-altitude flight target and the hierarchical warning scheme includes: The hierarchical warning scheme includes different warning level schemes corresponding to a high-risk area, a low-risk area, and a temporary risk area respectively; and Performing a warning according to the warning level scheme.

5. An alarm system for low-altitude flying targets based on the Beidou satellite navigation system, characterized in that, The low-altitude flight target warning system based on the Beidou satellite navigation system includes: A map acquisition unit for obtaining a high-precision three-dimensional urban map, where the three-dimensional urban map includes a preset no-fly zone, obstacle spatial information, and meteorological information; A strategy acquisition unit for determining a signal acquisition strategy within the preset no-fly zone according to the obstacle spatial information and the meteorological information, where the signal acquisition strategy includes acquiring multi-band signals of Beidou satellites and / or acquiring visual signals; An information determination unit for determining the position information of the low-altitude flight target according to the precision signal corresponding to the multi-band signal and / or the visual signal; and An alarm unit, configured to obtain a hierarchical alarm scheme corresponding to a preset no-fly zone, and perform an alarm based on the position information of the low-altitude flying target and the hierarchical alarm scheme.

6. The low-altitude flight target warning system based on the Beidou satellite navigation system according to claim 5, characterized in that, The policy acquisition unit is configured to: When the meteorological information is weather with visibility lower than a preset visibility threshold and there is no obstacle occlusion in the obstacle spatial information, the signal acquisition policy includes acquiring multi-band signals of Beidou satellites, and acquiring visual signals when the multi-band signals are interrupted; When the meteorological information is weather with visibility higher than a preset visibility threshold and there is no obstacle occlusion in the obstacle spatial information, continuously acquire visual signals and continuously acquire multi-band signals of Beidou satellites; and When there is obstacle occlusion in the obstacle spatial information, the signal acquisition policy includes acquiring multi-band signals of Beidou satellites.

7. The low-altitude flight target warning system based on the Beidou satellite navigation system according to claim 5, characterized in that, The information determination unit is configured to: Utilize integrated MEMS inertial navigation and visual SLAM technology to determine the first estimated position information corresponding to the visual signal; and / or Determine the precision signal corresponding to the multi-band signal based on differential enhancement technology, and determine the second estimated position information of the low-altitude flying target based on the precision signal; And Determine the position information of the low-altitude flying target according to a preset position definition relationship between the first estimated position information and the second estimated position information set in advance.

8. The low-altitude flight target warning method based on the Beidou satellite navigation system according to claim 5, wherein The hierarchical alarm scheme includes different alarm level schemes corresponding to a high-risk area, a low-risk area, and a temporary risk area respectively; and The alarm unit is configured to perform an alarm according to the alarm level scheme.

9. A machine-readable storage medium, on which instructions are stored, and the instructions are used to cause a machine to execute the low-altitude flying target alarm method based on the Beidou satellite navigation system according to any one of claims 1-4 above.

10. A processor, characterized in that, For running a program, wherein when the program is run, it is used to execute: the low-altitude flying target alarm method based on the Beidou satellite navigation system according to any one of claims 1-4.

Images