A non-enclosed area intrusion alerting and data analysis method

Abstract

A method for intrusion alarm and data analysis in non-enclosed areas, belonging to the field of non-enclosed area intrusion monitoring, includes the following steps: Step 1: Real-time acquisition of the movement trajectory of aircraft in the outer airspace of the non-enclosed area and real-time transmission to the processing terminal; Step 2: The processing terminal uses the line segment intersection method to determine whether an aircraft entering the monitoring range has intruded; Step 3: If the processing terminal determines that the aircraft is intruding, it immediately issues an intrusion warning; Step 4: If the processing terminal determines that the aircraft is not intruding, it calculates the distance between the aircraft and the boundary using point distance and line distance. This invention constructs a complete aircraft boundary monitoring mechanism and a closed-loop airspace monitoring system covering the entire chain of "pre-event warning - in-event alarm - post-event review," which can issue warnings when aircraft approach the boundary, issue alarms when intrusion is confirmed, and record relevant trajectories and judgment information throughout the process to support complete post-event review and analysis of intrusion events and accountability.

Description

Technical Field

[0001] This invention belongs to the field of intrusion monitoring in non-enclosed areas, specifically a method for intrusion alarm and data analysis in non-enclosed areas. Background Technology

[0002] With the gradual opening of low-altitude airspace and the widespread application of new types of aircraft such as drones, eVTOL (electric vertical takeoff and landing) aircraft, and general aviation aircraft, the need for airspace security, especially boundary monitoring of sensitive or restricted areas, is becoming increasingly urgent. Traditional airspace management largely relies on closed geofencing, which uses pre-defined closed polygonal areas (such as no-fly zones or restricted flight zones) to control aircraft access. When an aircraft approaches or crosses this closed boundary, ground systems or airborne equipment will trigger warnings or force it to return to its origin.

[0003] However, in real-world applications, many critical areas (such as power corridors, border lines, temporary construction airspace, airway edges, and river / railway lines) exhibit non-closed, linear, or open boundary characteristics, making them unsuitable for effective modeling using traditional closed fences. While these areas lack a complete "inside / outside" semantic, real-time monitoring of nearby flight activities is still necessary to prevent potential interference, intrusion, or security incidents.

[0004] Existing technologies face the following challenges when dealing with such non-closed boundaries: (1) The location determination method is not applicable: the traditional ray casting method or even-odd rule relies on closed polygons and cannot be directly used to determine whether the aircraft "intrudes" at the opening boundary; (2) Insufficient distance calculation accuracy: Most systems only calculate the minimum distance from the aircraft to the boundary vertex, ignoring the geometric continuity of the boundary line segment itself, resulting in a large deviation in distance estimation, which can easily cause false alarms or missed alarms; (3) Lack of graded response mechanism: Existing alarm systems usually only trigger actions after crossing the boundary, and lack graded warnings based on "proximity" (such as yellow warnings and red alarms). (4) Weak post-event analysis capability: Most systems focus on real-time interception but do not systematically record trajectories, judgment logic and timestamps, making it difficult to support accident review or responsibility determination.

[0005] Existing technical solutions are mainly reflected in the following two types of systems: (1) Unmanned aerial vehicle (UAV) control systems based on closed geofences, such as DJI’s Geo Zone system and NASA’s UTM (Unmanned Aircraft System Traffic Management) platform, all use closed polygons to define no-fly zones. Their core technologies include: constructing closed areas using the WGS-84 coordinate system; determining the aircraft status through Point-in-Polygon (PIP) algorithms (such as ray casting); and triggering onboard restrictions or ground alarms when the aircraft enters or approaches the fence.

[0006] Limitations: This type of solution cannot handle non-closed boundaries. For an open boundary line (such as a national border or a high-voltage power line corridor), the system cannot define "inside," and therefore cannot determine "intrusion" behavior or calculate a reasonable approach distance.

[0007] (2) Proximity detection methods based on line segment distance: Some studies (such as the IEEE paper "Real-time Proximity Monitoring for UAVs near Linear Infrastructure") propose modeling linear facilities such as power lines and pipelines as polylines, and realizing proximity alarms by calculating the vertical distance from the aircraft to the nearest line segment. The typical process is as follows: discretize the boundary into a sequence of points; traverse all line segments and calculate the shortest distance from the point to the line segment; if the minimum distance is lower than the threshold, an alarm is triggered.

[0008] Shortcomings: It only focuses on the distance dimension and lacks topological relationship determination of "whether it crosses the boundary", and cannot distinguish between "approaching from one side" and "having crossed to the other side"; it does not introduce a fast pruning mechanism, and the computational cost is large when there are many boundary points, making it difficult to meet the needs of high-frequency real-time monitoring; it does not have a complete early warning-alarm-review closed loop system and has limited functionality.

[0009] Existing technologies for monitoring aircraft in non-closed boundary areas generally suffer from problems such as missing positional semantics, coarse distance estimation, simplistic response mechanisms, and lack of behavior tracing capabilities. Therefore, there is an urgent need for a comprehensive technical solution that can accurately determine the relative positional relationship between the aircraft and the non-closed boundary, efficiently calculate the true shortest distance, and support tiered early warning and post-event review. Summary of the Invention

[0010] This invention provides a method for intrusion alarm and data analysis in non-enclosed areas to address the deficiencies in existing technologies.

[0011] This invention is achieved through the following technical solution: A method for intrusion alarm and data analysis in non-enclosed areas includes the following steps: Step 1: Acquire the motion trajectory of aircraft in the airspace surrounding the non-closed area in real time and transmit it to the processing terminal in real time; Step 2: The processing terminal uses the line segment intersection method to determine whether an aircraft entering the monitoring range has intruded. Step 3: If the processing terminal determines that the aircraft is in an intrusion state, it will immediately issue an intrusion warning; Step 4: If the processing terminal determines that the aircraft is in an unintrusive state, it calculates the distance between the aircraft and the boundary using point distance and line distance. Step 5: The processing terminal compares the distance between the aircraft and the boundary obtained in Step 3 with the warning distance. If the distance between the aircraft and the boundary is less than the warning distance, an intrusion warning is issued immediately. Step Six: Real-time monitoring and analysis of the aircraft's trajectory after the terminal aircraft enters the monitoring range, obtaining the aircraft's activity status, and using it for subsequent review and analysis.

[0012] As described above, the method for intrusion alarm and data analysis in a non-enclosed area involves the following steps in step one: real-time acquisition of the motion trajectory of aircraft in the outer airspace of the non-enclosed area using multi-source detection equipment deployed around the non-enclosed area (including but not limited to primary / secondary surveillance radars, ADS-B (Automatic Dependent Surveillance-Broadcast) ground stations, passive detection systems, and electro-optical camera groups). The system performs spatiotemporal alignment and fusion processing on the multi-source data to remove clutter and false targets, generating a standard trajectory message containing the aircraft number, longitude, latitude, altitude, speed, heading, and timestamp. This message is then transmitted reliably and in real-time to the processing terminal via wired or wireless communication links.

[0013] The non-enclosed area intrusion alarm and data analysis method described above includes a rapid rejection test and a cross-sectional test in step two.

[0014] The non-closed area intrusion alarm and data analysis method described above uses a rapid rejection experiment to determine whether the rectangle formed by the aircraft position and the monitoring point inside the boundary as diagonal lines intersects with the rectangle formed by two adjacent points on the boundary as diagonal lines. This determines whether the necessary conditions for line segment intersection are met. If they are met, it is initially determined to be an intrusion state; if not, it is determined to be a non-intrusion state.

[0015] The non-closed area intrusion alarm and data analysis method described above uses the cross-sectional experiment to determine whether the aircraft, whose position and the monitoring point inside the boundary are diagonally intersecting with two adjacent points on the boundary, meet the necessary and sufficient condition that the diagonal line intersects with the diagonal line. If the condition is met, the aircraft is determined to be in an intrusion state; otherwise, it is determined to be in a non-intrusion state.

[0016] In the above-described method for intrusion alarm and data analysis in a non-enclosed area, after calculating the point distance and line distance in step two, the processing terminal also needs to form a line segment by the aircraft position and the monitoring point position inside the boundary, and record the intersection count of the line segment with the boundary line. If the intersection count is even, the aircraft is determined to be inside the boundary; if the intersection count is odd, the aircraft is determined to be outside the boundary.

[0017] As described above, in the non-enclosed area intrusion alarm and data analysis method, the intrusion warning operation in step three is as follows: after the processing terminal determines that the aircraft has intruded, it immediately displays the aircraft icon on the electronic map interface and triggers the audible and visual alarm to emit a rapid alarm sound and a red flash; at the same time, the system automatically pops up an alarm window to display the number, location, speed, and intrusion time information of the intruding aircraft, and pushes the alarm information to the handheld terminal of the relevant management personnel in real time via SMS or dedicated communication link.

[0018] In the non-enclosed area intrusion alarm and data analysis method described above, step four involves calculating the point distance by finding the nearest point on the boundary between the aircraft's position and the boundary, traversing all points on the boundary, calculating the point distance, and obtaining the minimum value. The line distance calculation, based on the point distance, selects the points on both sides of the nearest point on the boundary, and then calculates the distance between the two line segments formed by the aircraft's position and the nearest point on the boundary, and takes the minimum of the two, which is the closest distance between the aircraft and the boundary line.

[0019] In the above-described method for intrusion alarm and data analysis in a non-enclosed area, the warning distance in step five is 1.5km.

[0020] As described above, in the non-enclosed area intrusion alarm and data analysis method, the intrusion warning operation in step five is as follows: After the processing terminal determines that the distance between the aircraft and the boundary is less than the warning distance, the aircraft icon on the electronic map interface is switched from its normal color to a bright yellow flashing icon, while an intermittent warning sound is emitted; the system automatically generates a semi-transparent warning light band at the edge of the interface to mark the boundary section that is about to be approached, and displays the real-time distance data of the aircraft and the estimated remaining time of intrusion; if the aircraft continues to approach the boundary, the system will broadcast voice prompts at a preset frequency.

[0021] The advantages of this invention are: This invention constructs a complete aircraft boundary monitoring mechanism and a closed-loop airspace monitoring system covering the entire chain of "pre-event warning - in-event alarm - post-event review". It can issue warnings when an aircraft approaches the boundary, issue alarms when an intrusion is confirmed, and record relevant trajectories and judgment information throughout the process to support a complete review and analysis of the intrusion event and to trace responsibility, thus meeting the full life cycle requirements of airspace safety management. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram illustrating the principle of the rapid rejection experiment of the present invention; Figure 2 This is a schematic diagram illustrating the principle of the straddle experiment of the present invention; Figure 3 This is a schematic diagram illustrating the principle of recording the intersection points of the aircraft position and the monitoring point position inside the boundary line, which form a line segment. Figure 4 This is a schematic diagram illustrating the principle of calculating the distance between the aircraft and the boundary according to the present invention. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] A method for intrusion alarm and data analysis in non-enclosed areas includes the following steps: Step 1: Acquire the motion trajectory of aircraft in the airspace surrounding the non-closed area in real time and transmit it to the processing terminal in real time; Step 2: The processing terminal uses the line segment intersection method to determine whether an aircraft entering the monitoring range has intruded. Step 3: If the processing terminal determines that the aircraft is in an intrusion state, it will immediately issue an intrusion warning; Step 4: If the processing terminal determines that the aircraft is in an unintrusive state, it calculates the distance between the aircraft and the boundary using point distance and line distance. Step 5: The processing terminal compares the distance between the aircraft and the boundary obtained in Step 3 with the warning distance. If the distance between the aircraft and the boundary is less than the warning distance, an intrusion warning is issued immediately. Step Six: Real-time monitoring and analysis of the aircraft's trajectory after the terminal aircraft enters the monitoring range, obtaining the aircraft's activity status, and using it for subsequent review and analysis.

[0026] Specifically, the operation method of the intrusion warning in step three of this embodiment is as follows: after the processing terminal determines that the aircraft has intruded, it immediately displays the aircraft icon on the electronic map interface and triggers the audible and visual alarm to emit a rapid alarm sound and a red flash; at the same time, the system automatically pops up an alarm window to display the number, location, speed and intrusion time information of the intruding aircraft, and pushes the alarm information to the handheld terminal of the relevant management personnel in real time via SMS or dedicated communication link.

[0027] Specifically, the line segment intersection method operation in step two of this embodiment includes a rapid repulsion experiment and a straddle experiment.

[0028] like Figure 1 As shown, more specifically, the rapid repulsion experiment described in this embodiment is used to determine whether the rectangle formed by the aircraft position and the monitoring point inside the boundary as a diagonal line (called line segment AB) intersects with the rectangle formed by two adjacent points on the boundary as a diagonal line (called line segment CD). This determines whether the necessary condition for line segment intersection is met. If it is met, it is initially determined to be an intrusion state; if it is not met, it is determined to be a non-intrusion state.

[0029] like Figure 2 As shown, more specifically, the straddling experiment described in this embodiment determines whether the necessary and sufficient condition for the aircraft's position and the monitoring point inside the boundary (referred to as line segment AB) to intersect with two adjacent points on the boundary (referred to as line segment CD) is met by using the vector product method. If the condition is met, the aircraft is determined to be in an intrusion state; otherwise, it is determined to be in a non-intrusion state.

[0030] like Figure 3 As shown, more specifically, in step two of this embodiment, after calculating the point distance and line distance, the processing terminal also needs to calculate the line segment formed by the aircraft position and the monitoring point position inside the boundary ( Figure 3 The system records the number of intersections between line segments RE1 and RE2 and the boundary line. If the number of intersections is even, the aircraft is determined to be inside the boundary; if the number of intersections is odd, the aircraft is determined to be outside the boundary.

[0031] Furthermore, the operation method of the intrusion warning in step three of this embodiment is as follows: after the processing terminal determines that the aircraft has intruded, it immediately displays the aircraft icon on the electronic map interface and triggers the audible and visual alarm to emit a rapid alarm sound and a red flash; at the same time, the system automatically pops up an alarm window to display the number, location, speed, and intrusion time information of the intruding aircraft, and pushes the alarm information to the handheld terminal of the relevant management personnel in real time via SMS or dedicated communication link.

[0032] like Figure 4As shown, further, in step four of this embodiment, the point distance calculation is used to find the aircraft's position ( Figure 4 The closest point on the boundary is (midpoint E). Figure 4 For the midpoint O), traverse all points on the boundary to calculate the point distance and obtain the minimum value; for the line distance calculation, based on the point distance, select the points on both sides of the nearest point on the boundary (referred to as points M and N respectively), and then calculate the distance between the two line segments (denoted as line segment OM and line segment ON) formed by the nearest point on the boundary and the points on both sides of the nearest point on the boundary. Take the minimum value of the two, which is the closest distance between the aircraft and the boundary line.

[0033] Furthermore, in step five of this embodiment, the warning distance is 1.5km.

[0034] Furthermore, the intrusion warning operation method in step five of this embodiment is as follows: after the processing terminal determines that the distance between the aircraft and the boundary is less than the warning distance, the aircraft icon on the electronic map interface is switched from the normal color to a bright yellow flashing, while an intermittent warning sound is emitted; the system automatically generates a semi-transparent warning light band at the edge of the interface to mark the boundary section that is about to be approached, and displays the real-time distance data of the aircraft and the estimated remaining time of intrusion; if the aircraft continues to approach the boundary, the system will broadcast voice prompt information in a loop at a preset frequency.

[0035] Example: Taking the intrusion alarm of a non-closed area in the airspace protection zone around an airport as an example, the present invention will be further described in detail.

[0036] A certain airport is surrounded by a large open area. The boundary of its airspace protection zone is not enclosed by a physical wall or fence, but rather by a virtual boundary defined by an electronic map. To prevent drones, birds, or low-altitude, slow-moving small aircraft from accidentally entering and affecting flight safety, the alarm and analysis system of this invention is deployed.

[0037] Step 1: Real-time Data Acquisition ADS-B ground receiving stations, low-altitude surveillance radar, and electro-optical camera arrays were deployed at control towers and high-altitude locations around the airport. The system captures real-time data on aircraft (including UAVs and general aviation aircraft) within a 15-kilometer radius of the outer airspace. When a UAV takes off from approximately 8 kilometers from the airport and flies towards it, the radar and ADS-B fused data generate the UAV's real-time trajectory, including its position (118.XX°E, 31.XX°N), altitude (120 meters), speed (15 meters per second), and heading (270°), which is then transmitted back to the processing terminal at the monitoring center in real time via a fiber optic network.

[0038] Step 2: Intrusion Detection The built-in line segment intersection algorithm in the processing terminal begins operation. The system calculates the intersection of the UAV's current motion vector (position and velocity direction) with the predefined airspace protection zone boundary (a non-closed polygon composed of multiple line segments) on the electronic map. The calculation shows that the UAV's current extended heading will intersect with the boundary line segment in approximately 40 seconds, and since the UAV has not yet entered the boundary, the system initially determines the current state to be "non-intrusive."

[0039] Step 3: Intrusion warning triggered Monitoring personnel continued to observe. After approximately 35 seconds, the drone did not change its course, and its calculated position coordinates showed it had crossed the virtual boundary line. The processing terminal immediately identified it as an "intrusion." On the monitoring room's large screen, the drone's icon instantly turned red and flashed rapidly, while a high-frequency "beep beep beep" audible and visual alarm sounded. The system automatically popped up a detailed information window, displaying "Drone XXX, altitude 120 meters, speed 15 meters / second, illegally crossed the boundary at 09:47:33, boundary crossing coordinates (longitude 92.XX° East, latitude 27.XX° North)." This alarm information was simultaneously sent to the handheld terminals of the field management personnel.

[0040] Step 4: Distance Calculation in Unintruded State Assuming another helicopter is cruising outside the boundary, not intersecting the boundary line segment, and is in a "non-intrusion" state, the system immediately activates the point distance and line distance calculation module. By calculating the vertical distance from the helicopter's current position (point) to the nearest boundary line segment (line), it is determined that the current distance to the boundary is approximately 350 meters.

[0041] Step 5: Intrusion warning triggered The system compares the calculated distance of 350 meters with the preset warning distance (e.g., 500 meters). Since 350 meters is less than 500 meters, the system determines that "a warning is needed." At this time, the helicopter icon on the monitoring screen changes from its normal color to yellow and flashes slowly, while emitting intermittent "beep-beep-beep" warning sounds. A yellow arc-shaped light band appears at the edge of the screen near the helicopter, and a floating window displays the boundary warning information.

[0042] Step Six: Track Monitoring and Analysis From the moment the helicopter first entered the 15-kilometer monitoring range, the system recorded its flight trajectory, speed changes, and heading data throughout the entire process. Afterwards, if an investigation and analysis of this boundary crossing incident is required, management personnel can access historical data to fully reconstruct the helicopter's trajectory from its appearance, approach to the boundary, boundary crossing, and subsequent flight, analyzing its possible takeoff location, flight intentions, and control patterns, providing crucial support for subsequent alert deployments and countermeasures.

[0043] As can be seen from the above embodiments, the present invention realizes closed-loop management of non-enclosed areas from remote early warning, critical alarm, intrusion alarm to review analysis, effectively improving the low-altitude safety protection capability of the area.

[0044] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for intrusion alarm and data analysis in non-enclosed areas, characterized in that: Includes the following steps: Step 1: Acquire the motion trajectory of aircraft in the airspace surrounding the non-closed area in real time and transmit it to the processing terminal in real time; Step 2: The processing terminal uses the line segment intersection method to determine whether an aircraft entering the monitoring range has intruded. Step 3: If the processing terminal determines that the aircraft is in an intrusion state, it will immediately issue an intrusion warning; Step 4: If the processing terminal determines that the aircraft is in an unintrusive state, it calculates the distance between the aircraft and the boundary using point distance and line distance. Step 5: The processing terminal compares the distance between the aircraft and the boundary obtained in Step 3 with the warning distance. If the distance between the aircraft and the boundary is less than the warning distance, an intrusion warning is issued immediately. Step Six: Real-time monitoring and analysis of the aircraft's trajectory after the terminal aircraft enters the monitoring range, obtaining the aircraft's activity status, and using it for subsequent review and analysis.

2. The method for intrusion alarm and data analysis in a non-enclosed area according to claim 1, characterized in that: The operation of acquiring the motion trajectory of the aircraft in the outer airspace of the non-closed area in step one is as follows: the aircraft target in the outer airspace is captured in real time by multi-source detection equipment deployed around the non-closed area; the multi-source data is spatiotemporally aligned and fused to remove clutter and false targets, and a standard trajectory message containing the aircraft number, longitude, latitude, altitude, speed, heading and timestamp is generated and transmitted to the processing terminal in real time and reliably through wired or wireless communication links.

3. The method for intrusion alarm and data analysis in a non-enclosed area according to claim 1, characterized in that: The line segment intersection method operation in step two includes a rapid repulsion experiment and a straddle experiment.

4. The method for intrusion alarm and data analysis in a non-enclosed area according to claim 3, characterized in that: The rapid repulsion test is used to determine whether the rectangle formed by the aircraft position and the monitoring point inside the boundary as diagonal lines intersects with the rectangle formed by two adjacent points on the boundary as diagonal lines. This determines whether the necessary conditions for line segment intersection are met. If they are met, it is initially determined to be an intrusion state; if not, it is determined to be a non-intrusion state.

5. The method for intrusion alarm and data analysis in a non-enclosed area according to claim 3, characterized in that: The aforementioned straddle experiment, for aircraft initially determined to be in an intrusion state by the rapid repulsion experiment, uses the vector product method to determine whether the necessary and sufficient condition is met for the aircraft's position and the monitoring point inside the boundary to form a diagonal line intersecting with two adjacent points on the boundary. If the condition is met, it is determined to be in an intrusion state; otherwise, it is determined to be in a non-intrusion state.

6. The method for intrusion alarm and data analysis in a non-enclosed area according to claim 1, characterized in that: In step two, after calculating the point distance and line distance, the processing terminal also needs to form a line segment by the aircraft position and the monitoring point position inside the boundary, and record the intersection count of the line segment with the boundary line. If the intersection count is even, the aircraft is determined to be inside the boundary; if the intersection count is odd, the aircraft is determined to be outside the boundary.

7. The method for intrusion alarm and data analysis in a non-enclosed area according to claim 1, characterized in that: The operation method of the intrusion warning in step three is as follows: after the processing terminal determines that the aircraft has intruded, it immediately displays the aircraft icon on the electronic map interface and triggers the audible and visual alarm to emit a rapid alarm sound and a red flash; at the same time, the system automatically pops up an alarm window to display the number, location, speed and intrusion time information of the intruding aircraft, and pushes the alarm information to the handheld terminal of the relevant management personnel in real time via SMS or dedicated communication link.

8. The method for intrusion alarm and data analysis in a non-enclosed area according to claim 1, characterized in that: In step four, the point distance calculation involves finding the nearest point on the boundary where the aircraft's position is located, traversing all points on the boundary, calculating the point distance, and obtaining the minimum value. The line distance calculation, based on the point distance, involves selecting the points on both sides of the nearest point on the boundary, and then calculating the distance between the two line segments formed by the aircraft's position and the nearest point on the boundary and the points on both sides of the selected nearest point on the boundary. The minimum value of these two values ​​is the closest distance between the aircraft and the boundary line.

9. The method for intrusion alarm and data analysis in a non-enclosed area according to claim 1, characterized in that: The warning distance in step five is 1.5km.

10. The method for intrusion alarm and data analysis in a non-enclosed area according to claim 1, characterized in that: The intrusion warning operation in step five is as follows: after the processing terminal determines that the distance between the aircraft and the boundary is less than the warning distance, the aircraft icon on the electronic map interface is switched from the normal color to a bright yellow flashing, and an intermittent warning sound is emitted at the same time; a semi-transparent warning light band is automatically generated at the edge of the interface to mark the boundary section that is about to be approached, and the real-time distance data of the aircraft and the estimated remaining time of intrusion are displayed; if the aircraft continues to approach the boundary, the system will broadcast voice prompts in a loop at a preset frequency.

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