Low-altitude continuous coverage performance test method and system based on communication base station
By using drones to collect and reconstruct low-altitude coverage maps and 3D radiation maps of base stations through location correction, the problem of insufficient signal coverage in low-altitude areas in traditional methods has been solved, achieving efficient assessment and improved accuracy of low-altitude areas for base stations.
Patent Information
- Application Number
- CN202512025869.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-30
- Publication Date
- 2026-02-17
AI Technical Summary
Traditional communication base stations suffer from insufficient signal coverage and unstable access in low-altitude areas. They also lack systematic and effective testing and evaluation methods, making it difficult to fully grasp the communication performance of base stations for low-altitude mobile terminals.
UAVs were used to collect radiation characteristic data. The low-altitude coverage map of the communication base station was reconstructed by combining UAV position correction and covariance matrix. The three-dimensional radiation map was reconstructed by spherical coordinate system to evaluate the low-altitude continuous coverage capability of the base station.
It improves the accuracy and repeatability of low-altitude continuous coverage performance, reduces the impact of measurement noise and location errors, and enhances the efficiency and accuracy of radiation coverage assessment in low-altitude areas.
Smart Images
Figure CN121547802A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of wireless communication transmission technology, specifically, it relates to a method and system for testing the low-altitude continuous coverage performance based on a communication base station. Background Technology
[0002] With the rapid development of low-altitude mobile devices such as drones and low-altitude manned aircraft, the demand for wireless access and communication in low-altitude areas has increased dramatically. Traditional communication base stations are mainly designed for ground-based mobile terminal access. When applied to low-altitude mobile terminal communication, they face problems such as insufficient signal coverage, unstable access, and severe signal fading. To solve this problem, existing base stations can be upgraded to improve their signal coverage in low-altitude areas. However, there is a lack of systematic and effective testing and evaluation methods, making it difficult to fully understand the communication performance of base stations for low-altitude mobile terminals. Therefore, there is an urgent need for a testing system and corresponding methods that can accurately evaluate the continuous low-altitude coverage performance of communication base stations, providing support for the planning, deployment, and optimization of low-altitude communication networks.
[0003] Three-dimensional low-altitude coverage maps visually reflect the continuous coverage capability of base stations in low-altitude areas and are an important means of evaluating the low-altitude coverage performance of base stations. Mapping base station signal coverage maps in low-altitude areas often faces a series of complex challenges. For example, the limited number of data collection points and time constraints make accurate mapping of three-dimensional low-altitude coverage maps very difficult; the propagation path between base stations and mobile terminals in low-altitude areas is greatly affected by terrain, and using ground measurement points for testing cannot effectively evaluate the vertical coverage performance of base station signals, making it difficult to accurately quantify signal blind spots in low-altitude areas.
[0004] Three-dimensional radiation maps reflect the radiation characteristics of a base station in different directions and are an important indicator for evaluating its low-altitude coverage capability. Traditional methods for testing base station radiation characteristics typically involve measurements in an indoor microwave anechoic chamber, which requires close measurement distances and minimal external electromagnetic interference. However, in real-world outdoor applications, the complex and variable environment makes traditional testing methods unsuitable.
[0005] In recent years, thanks to their advantages such as flexible deployment and efficient data acquisition, UAV platforms have been widely used in testing tasks for 3D low-altitude coverage maps and 3D radiation maps, providing an effective means to evaluate the continuous coverage capability of base stations in low-altitude areas. However, such UAV-based testing methods still face problems in actual deployment, such as limited measurement accuracy, sensitivity to environmental interference, and poor adaptability to different types of antennas, which restricts their reliable application in complex low-altitude scenarios. Summary of the Invention
[0006] To address the problems existing in the prior art, this invention provides a method and system for testing the low-altitude continuous coverage performance of communication base stations. It comprehensively considers the influence of spatial location and environmental factors on the radiation characteristics of communication base stations, and realizes the accurate reconstruction of the low-altitude coverage map and the three-dimensional radiation map of communication base stations, greatly improving the accuracy of the low-altitude continuous coverage performance of communication base stations.
[0007] To achieve the above technical objectives, the present invention adopts the following technical solution: A method for testing the low-altitude continuous coverage performance based on a communication base station includes the following steps: Step S1: Fly the UAV around the communication base station along a preset trajectory, collect radiation characteristic data, and record the UAV's position and pose when collecting radiation characteristic data; Step S2: Correct the drone's position information based on the drone's pose, GPS antenna installation position, and airborne antenna installation position to obtain the corrected drone position; Step S3: Construct a noisy covariance matrix based on the corrected UAV location, and reconstruct the low-altitude coverage map of the communication base station by combining it with the collected radiation characteristic data; Step S4: Determine the continuous low-altitude coverage area based on the low-altitude coverage map of the communication base station, and evaluate the low-altitude airspace radiation coverage capability of the communication base station. Step S5: Calculate the relative transmitting antenna gain of the UAV based on the corrected UAV position, the position of the communication base station, and the receiving antenna gain of the UAV; Step S6: Map the corrected UAV position to a spherical coordinate system centered on the communication base station, and map the UAV's relative transmit antenna gain to the corresponding position in the spherical coordinate system; Step S7: Reconstruct the three-dimensional radiation map of the communication base station based on the relative transmit antenna gain of the UAV in the spherical coordinate system; Step S8: Determine the continuous coverage area in the low-altitude direction based on the reconstructed three-dimensional radiation map of the communication base station, and evaluate the low-altitude radiation coverage capability of the communication base station.
[0008] Furthermore, based on the communication frequency of the communication base station Antenna aperture of communication base stations Determine the minimum radius of the preset trajectory :
[0009] in, It represents the speed of light.
[0010] Further, step S2 includes the following sub-steps: Step S2.1: Transfer the UAV's position information to the geodetic coordinate system. Convert the UAV position to a geocentric coordinate system :
[0011] in, Indicates that the drone is in The longitude, latitude, and altitude of each collection point Indicates that the drone is in The radius of curvature of the circle at each sampling point. , Represents the semi-major axis of the Earth's ellipsoid. This represents the first eccentricity of the Earth's ellipsoid. , Represents the minor semi-axis of the Earth's ellipsoid; Step S2.2: Position the UAV in the geocentric coordinate system Based on the relative positions of the drone's GPS antenna installation location and the airborne antenna installation location Calculate the position of the UAV after translation transformation : ; Step S2.3: Based on the UAV pose Calculate the rotation matrix :
[0012] in, These represent the drones in the [number]th [month]. Roll angle, pitch angle, and yaw angle at each data collection point Indicates that the drone is in About the collection points The rotation matrix of the axis of rotation. ; Indicates that the drone is in About the collection points The rotation matrix of the axis of rotation. ; Indicates that the drone is in About the collection points The rotation matrix of the axis of rotation. ; Step S2.4: Transform the UAV position using the rotation matrix. Make corrections to obtain the corrected drone position. : .
[0013] Furthermore, step S3 includes the following sub-steps: Step S3.1: Assemble all corrected UAV positions into a known position matrix. All collected radiation characteristic data are combined to form a known radiation matrix. ,in, Indicates the number of collection points. Indicates no first The drone's position was corrected based on the data collection points. , Drones in Radiation characteristic data collected from each sampling point; Step S3.2: Calculate the covariance matrix between the acquisition points based on the known location matrix. And add noise to construct a noisy covariance matrix. :
[0014] in, The covariance matrix representing the noise; Step S3.3: Assemble the uncollected drone locations into an uncollected location matrix. Calculate the covariance matrix between the uncollected location matrix and the known location matrix. By combining the noisy covariance matrix and the known radiation matrix, the uncollected radiation matrix is calculated:
[0015] Step S3.4: Combine the known radiation matrix and the uncollected radiation matrix to form a low-altitude coverage map of the communication base station.
[0016] Furthermore, step S4 includes the following sub-steps: Step S4.1: Set the spatial coverage threshold. Set the area with radiation characteristic data below the spatial coverage threshold in the low-altitude coverage map of the communication base station to 0, and set the other area to 1. Step S4.2: Perform three-dimensional connected component analysis on all regions set to 1 to obtain the maximum connected radiation coverage area, and calculate the low-altitude airspace radiation coverage capability of the communication base station. :
[0017] in, This represents the area of the maximum connected radiation coverage region. This indicates the area of the assessment region for the low-altitude coverage map of the communication base station.
[0018] Furthermore, step S5 includes the following sub-steps: Step S5.1: Locate the communication base station in the geodetic coordinate system. Transformation of communication base station location into geocentric coordinate system The drone position was corrected by combining the data collection points. Find the position of the reflection point corresponding to each acquisition point. :
[0019] in, This indicates the longitude, latitude, and altitude of the communication base station. Represents the semi-major axis of the Earth's ellipsoid. Represents the minor semi-axis of the Earth's ellipsoid; Step S5.2: Correcting the UAV position using the data collection points The corresponding reflection point position and the location of communication base stations in the geocentric spatial coordinate system Calculate the distance between the data collection point and the communication base station respectively. Distance between the sampling point and the reflection point and the distance between the reflection point and the communication base station Determine the distance difference Phase difference and the angle formed by the collection point, the reflection point and the communication base station. :
[0020]
[0021]
[0022] in, Indicates the communication frequency of the communication base station. Represents the speed of light; Step S5.3: Determine the relative dielectric constant based on the ground environment where the communication base station is located. The angle formed by the collection point, the reflection point, and the communication base station Calculate polarization coefficient With reflection coefficient :
[0023]
[0024] in, Represents the vertical polarization coefficient. , Represents the horizontal polarization coefficient. ; Step S5.4: Increase the gain of the UAV's receiving antenna. Combined with reflection coefficient and phase difference Calculate the transmit antenna gain of the UAV. :
[0025] in, Indicates the drone's transmission power. This indicates the receiving power of the drone; Step S5.5: Based on the UAV's transmit antenna gain Calculate the relative transmit antenna gain of the UAV with the maximum transmit antenna gain. : .
[0026] Furthermore, the process of mapping the corrected UAV position to a spherical coordinate system centered on the communication base station in step S6 is as follows:
[0027]
[0028] in, This indicates the location of the communication base station in the geocentric spatial coordinate system. Indicates the corrected drone position. This indicates the distance between the data collection point and the communication base station. Indicates that the drone is in The polar angle corresponding to each collection point Indicates that the drone is in The azimuth angle corresponding to each collection point.
[0029] Furthermore, step S7 includes the following sub-steps: Step S7.1: Calculate the distance between the collected points and the uncollected points based on the locations of the UAV's data collection points in the spherical coordinate system. :
[0030] in, Indicates that the drone is in Polar angle and azimuth angle of each sampling point Indicates points not collected by drone The polar angle and azimuth angle at the location, Indicates the arc length of a sphere; Step S7.2: According to Communication frequency of communication base station The altitude of the drone's onboard antenna for data acquisition. Calculate path loss :
[0031] in, and Correction parameters related to the propagation environment, The shadow fading factor; Step S7.3: Based on path loss Calculate weights ,in, Indicates the number of data collection points; Step S7.4: Adjust the weights The relative transmit antenna gain of the unsampled points is calculated by combining the relative transmit antenna gain of the UAV sampling points in the spherical coordinate system. :
[0032] in, This represents the relative transmit antenna gain of the UAV sampling point in the spherical coordinate system. Step S7.5: Repeat steps S7.1-S7.4 until the relative transmit antenna gain of all unsampled points is obtained. The relative transmit antenna gain of the UAV in the spherical coordinate system and the relative transmit antenna gain of all unsampled points are used to form a three-dimensional radiation map of the communication base station.
[0033] Further, step S8 includes the following sub-steps: Step S8.1: Set the directional coverage threshold, set the area in the three-dimensional radiation map of the communication base station with a gain lower than the directional coverage threshold to 0, and set the remaining area to 1; Step S8.2: Perform three-dimensional connected component analysis on all regions set to 1 to obtain the maximum connected radiation coverage area, and calculate the low-altitude radiation coverage capability of the communication base station. :
[0034] in, This represents the area of the maximum connected radiation coverage region. This represents the area of the evaluation region in the three-dimensional radiation map of the communication base station.
[0035] Furthermore, the present invention also provides a low-altitude continuous coverage performance testing system based on a communication base station, comprising: a data acquisition module, a spatial position correction module, a low-altitude coverage map reconstruction module, a transmission gain calculation module, a three-dimensional radiation map reconstruction module, and a low-altitude continuous coverage evaluation module; The data acquisition module is used to collect radiation characteristic data through the UAV, and to collect the position information and pose of the UAV during the radiation characteristic data acquisition. The spatial position correction module is used to correct the drone's position information based on the drone's pose, GPS antenna installation position, and airborne antenna installation position to obtain the corrected drone position. The low-altitude coverage map reconstruction module is used to construct a noisy covariance matrix based on the corrected UAV position, and reconstruct the low-altitude coverage map of the communication base station by combining the collected radiation characteristic data. The transmit gain calculation module is used to calculate the relative transmit antenna gain of the UAV based on the corrected UAV position, the position of the communication base station, and the receive antenna gain of the UAV. The three-dimensional radiation map reconstruction module is used to map the corrected UAV position to a spherical coordinate system centered on the communication base station, and reconstruct the three-dimensional radiation map of the communication base station based on the relative transmit antenna gain of the UAV in the spherical coordinate system. The low-altitude continuous coverage assessment module is used to assess the low-altitude airspace radiation coverage capability of the communication base station based on the low-altitude coverage map of the communication base station, and to assess the low-altitude directional radiation coverage capability of the communication base station based on the reconstructed three-dimensional radiation map of the communication base station.
[0036] Compared with the prior art, the present invention has the following beneficial effects: (1) The method and system for testing the low-altitude continuous coverage performance of communication base stations in this invention compensates for the position deviation of the collection points, constructs a noisy covariance matrix by correcting the position of the UAV, and reconstructs the low-altitude coverage map of the communication base station by combining the collected radiation characteristic data. By compensating for the position deviation of the UAV collection points, the spatial uncertainty introduced by positioning and attitude is explicitly modeled in statistical form. On this basis, radiation characteristic data is fused to interpolate and reconstruct the unsampled area, thereby effectively reducing the coverage misjudgment caused by sparse sampling, measurement noise and position error, and ensuring the accuracy and repeatability of low-altitude continuous coverage area extraction and low-altitude airspace radiation coverage capability assessment. (2) The method and system for testing the low-altitude continuous coverage performance of communication base stations in this invention compensates for the error of the test results by the position deviation of the sampling points and the channel propagation characteristics. It reconstructs the three-dimensional radiation map of the communication base station by the relative transmitting antenna gain of the UAV in the spherical coordinate system. Taking into account the environmental influences such as propagation path loss and ground reflection, it obtains the relative transmitting antenna gain of the UAV by inverting the receiving power and receiving antenna gain, and maps the sampling points to the spherical coordinate system centered on the base station. This can effectively suppress the errors introduced by multipath and measurement noise, and improve the integrity and direction consistency of the radiation pattern.
[0037] In summary, this invention utilizes drones to collect radiation data in the vertical airspace of communication base stations, enabling rapid assessment of low-altitude signal coverage capabilities. The testing is flexible, has a wide coverage area, and can more efficiently evaluate the radiation coverage performance of low-altitude areas. Attached Figure Description
[0038] Figure 1 This is a flowchart of the low-altitude continuous coverage performance testing method based on a communication base station according to the present invention; Figure 2This is a low-altitude coverage map of a communication base station under an example. Figure 3 This is a radiation diagram of the communication base station E-plane under the embodiment; Figure 4 This is a radiation diagram of the H-plane of the communication base station in the embodiment. Figure 5 This is a three-dimensional radiation diagram of a communication base station in an example embodiment. Detailed Implementation
[0039] The technical solution of the present invention will be further explained and described below with reference to the accompanying drawings.
[0040] like Figure 1 This is a flowchart of the low-altitude continuous coverage performance testing method based on a communication base station according to the present invention. The low-altitude continuous coverage performance testing method includes the following steps: Step S1: Fly the drone around the communication base station along a preset trajectory to collect radiation characteristic data. And record the location information of the UAV when collecting radiation characteristic data. and position ,in, Indicates that the drone is in The longitude, latitude, and altitude of each collection point These represent the drones in the [number]th [month]. The roll angle, pitch angle, and yaw angle of each data point.
[0041] When a drone flies around a communication base station along a preset trajectory, it needs to adjust the communication frequency of the base station accordingly. Antenna aperture of communication base stations Determine the minimum radius of the preset trajectory :
[0042] in, It represents the speed of light.
[0043] Step S2: Since there is a deviation between the location collected by the UAV and the actual location of the airborne receiving antenna, and attitude changes amplify this installation deviation, the UAV's position information is corrected based on the UAV's pose, GPS antenna installation location, and airborne antenna installation location to obtain the corrected UAV position. Correcting the position using the UAV's attitude and antenna installation relationship aligns the sampling points with the actual sampling location, reducing systematic errors and thus improving the accuracy and stability of subsequent coverage / radiation map reconstruction and low-altitude coverage capability assessment. This includes the following sub-steps: Step S2.1: Transfer the UAV's position information to the geodetic coordinate system. Convert the UAV position to a geocentric coordinate system :
[0044] in, Indicates that the drone is in The radius of curvature of the circle at each sampling point. , Represents the semi-major axis of the Earth's ellipsoid. This represents the first eccentricity of the Earth's ellipsoid. , Represents the minor semi-axis of the Earth's ellipsoid; Step S2.2: Position the UAV in the geocentric coordinate system Based on the relative positions of the drone's GPS antenna installation location and the airborne antenna installation location Calculate the position of the UAV after translation transformation : ; Step S2.3: Based on the UAV pose Calculate the rotation matrix :
[0045] in, Indicates that the drone is in About the collection points The rotation matrix of the axis of rotation. ; Indicates that the drone is in About the collection points The rotation matrix of the axis of rotation. ; Indicates that the drone is in About the collection points The rotation matrix of the axis of rotation. ; Step S2.4: Transform the UAV position using the rotation matrix. Make corrections to obtain the corrected drone position. : .
[0046] Step S3: To address the issue of limited and noisy UAV sampling points leading to discontinuous coverage maps, a noisy covariance matrix is constructed based on the corrected UAV locations. This matrix is then combined with the collected radiation characteristic data to reconstruct the low-altitude coverage map of the communication base station. Statistical reconstruction of unsampled areas improves the continuity and noise resistance of the coverage map, stabilizes coverage boundaries, and thus enhances the accuracy of low-altitude airspace radiation coverage capability assessment. This includes the following sub-steps: Step S3.1: Assemble all corrected UAV positions into a known position matrix. All collected radiation characteristic data are combined to form a known radiation matrix. ,in, Indicates the number of collection points. Indicates no first The drone's position was corrected based on the data collection points. , Drones in Radiation characteristic data collected from each sampling point; Step S3.2: Calculate the covariance matrix between the acquisition points based on the known location matrix. And add noise to construct a noisy covariance matrix. :
[0047] in, , and Let represent any collection point in the known position matrix, , Represents Euclidean distance. Indicates the width parameter. The covariance matrix representing the noise; Step S3.3: Assemble the uncollected drone locations into an uncollected location matrix. Calculate the covariance matrix between the uncollected location matrix and the known location matrix. By combining the noisy covariance matrix and the known radiation matrix, the uncollected radiation matrix is calculated:
[0048] Step S3.4: Combine the known radiation matrix and the uncollected radiation matrix to form a low-altitude coverage map of the communication base station.
[0049] Step S4: Determine the continuous low-altitude coverage area based on the low-altitude coverage map of the communication base station, and evaluate the low-altitude airspace radiation coverage capability of the communication base station; including the following sub-steps: Step S4.1: Set the spatial coverage threshold. Set the area with radiation characteristic data below the spatial coverage threshold in the low-altitude coverage map of the communication base station to 0, and set the other area to 1. Step S4.2: Perform three-dimensional connected component analysis on all regions set to 1 to obtain the maximum connected radiation coverage area, and calculate the low-altitude airspace radiation coverage capability of the communication base station. It can simultaneously reflect the radiation coverage range and coverage penetration. The larger the CCVR, the more continuous and penetrable the effective coverage area formed in the low-altitude airspace, and the stronger the low-altitude airspace coverage capability of the base station.
[0050] in, This represents the area of the maximum connected radiation coverage region. This indicates the area of the assessment region for the low-altitude coverage map of the communication base station.
[0051] Step S5: To address the issue of received power being affected by both distance attenuation and multipath reflection, which would lead to distortion when directly used for radiation pattern reconstruction, the relative transmit antenna gain of the UAV is calculated based on the corrected UAV position, the communication base station position, and the UAV's receive antenna gain. This reduces interference from channel and environmental factors, making the 3D radiation pattern closer to the true directional radiation characteristics of the base station, thereby improving the accuracy of low-altitude directional coverage assessment. This includes the following sub-steps: Step S5.1: Locate the communication base station in the geodetic coordinate system. Transformation of communication base station location into geocentric coordinate system The drone position was corrected by combining the data collection points. Find the position of the reflection point corresponding to each acquisition point. :
[0052] in, This indicates the longitude, latitude, and altitude of the communication base station. Represents the semi-major axis of the Earth's ellipsoid. Represents the minor semi-axis of the Earth's ellipsoid; Step S5.2: Correcting the UAV position using the data collection points The corresponding reflection point position and the location of communication base stations in the geocentric spatial coordinate system Calculate the distance between the data collection point and the communication base station respectively. Distance between the sampling point and the reflection point and the distance between the reflection point and the communication base station Determine the distance difference Phase difference and the angle formed by the collection point, the reflection point and the communication base station. :
[0053]
[0054]
[0055] in, Indicates the communication frequency of the communication base station. Represents the speed of light; Step S5.3: Determine the relative dielectric constant based on the ground environment where the communication base station is located. The angle formed by the collection point, the reflection point, and the communication base station Calculate polarization coefficient With reflection coefficient :
[0056]
[0057] in, Represents the vertical polarization coefficient. , Represents the horizontal polarization coefficient. ; Step S5.4: Increase the gain of the UAV's receiving antenna. Combined with reflection coefficient and phase difference Calculate the transmit antenna gain of the UAV. :
[0058] in, Indicates the drone's transmission power. This indicates the receiving power of the drone; Step S5.5: Based on the UAV's transmit antenna gain Calculate the relative transmit antenna gain of the UAV with the maximum transmit antenna gain. : .
[0059] Step S6: Map the corrected UAV position to a spherical coordinate system centered on the communication base station, and map the UAV's relative transmit antenna gain to the corresponding position in the spherical coordinate system. This unifies the spatial sampling into angle domain data, reduces computational complexity, and facilitates subsequent radiation pattern reconstruction.
[0060] The process of mapping the corrected UAV position to a spherical coordinate system centered on the communication base station in this invention is as follows:
[0061]
[0062] in, This indicates the location of the communication base station in the geocentric spatial coordinate system. Indicates the corrected drone position. This indicates the distance between the data collection point and the communication base station. Indicates that the drone is in The polar angle corresponding to each collection point Indicates that the drone is in The azimuth angle corresponding to each collection point.
[0063] Step S7: To address the issue of incomplete 3D radiation maps caused by sparse and uneven sampling in the spherical angle domain, the 3D radiation map of the communication base station is reconstructed based on the relative transmit antenna gain of the UAV in the spherical coordinate system. By weighting the relative transmit gain of unsampled directions in the angle domain using arc length distance and path loss weights, the integrity and continuity of the radiation map can be improved, thereby enhancing the accuracy of low-altitude radiation coverage capability assessment. This includes the following sub-steps: Step S7.1: Calculate the distance between the collected points and the uncollected points based on the locations of the UAV's data collection points in the spherical coordinate system. :
[0064] in, Indicates that the drone is in Polar angle and azimuth angle of each sampling point Indicates points not collected by drone The polar angle and azimuth angle at the location, Indicates the arc length of a sphere; Step S7.2: According to Communication frequency of communication base station The altitude of the drone's onboard antenna for data acquisition. Calculate path loss :
[0065] in, and Correction parameters related to the propagation environment, The shadow fading factor; Step S7.3: Based on path loss Calculate weights ,in, Indicates the number of data collection points; Step S7.4: Adjust the weights The relative transmit antenna gain of the unsampled points is calculated by combining the relative transmit antenna gain of the UAV sampling points in the spherical coordinate system. :
[0066] in, This represents the relative transmit antenna gain of the UAV sampling point in the spherical coordinate system. Step S7.5: Repeat steps S7.1-S7.4 until the relative transmit antenna gain of all unsampled points is obtained. The relative transmit antenna gain of the UAV in the spherical coordinate system and the relative transmit antenna gain of all unsampled points are used to form a three-dimensional radiation map of the communication base station.
[0067] Step S8: Determine the continuous coverage area in the low-altitude direction based on the reconstructed three-dimensional radiation map of the communication base station, and evaluate the low-altitude radiation coverage capability of the communication base station; including the following sub-steps: Step S8.1: Set the directional coverage threshold, set the area in the three-dimensional radiation map of the communication base station with a gain lower than the directional coverage threshold to 0, and set the remaining area to 1; Step S8.2: Perform three-dimensional connected component analysis on all regions set to 1 to obtain the maximum connected radiation coverage area, and calculate the low-altitude radiation coverage capability of the communication base station. It also characterizes the effective radiation range and penetration in the low-altitude direction. The larger the CAVR, the wider and more continuous the available radiation coverage formed by the communication base station in the relevant low-altitude direction, and the stronger the radiation coverage capability in the low-altitude direction.
[0068] in, This represents the area of the maximum connected radiation coverage region. This represents the area of the evaluation region in the three-dimensional radiation map of the communication base station.
[0069] In one technical solution of the present invention, a low-altitude continuous coverage performance testing system based on a communication base station is also provided, including: a data acquisition module, a spatial position correction module, a low-altitude coverage map reconstruction module, a transmission gain calculation module, a three-dimensional radiation map reconstruction module, and a low-altitude continuous coverage evaluation module. The data acquisition module is used to collect radiation characteristic data from the UAV and to collect the UAV's position and pose information during the data acquisition process. The spatial position correction module is used to correct the drone's position information based on the drone's pose, GPS antenna installation position, and airborne antenna installation position, thereby obtaining the corrected drone position. The low-altitude coverage map reconstruction module is used to construct a noisy covariance matrix based on the corrected UAV position, and reconstruct the low-altitude coverage map of the communication base station by combining the collected radiation characteristic data. The transmit gain calculation module is used to calculate the relative transmit antenna gain of the UAV based on the corrected UAV position, the position of the communication base station, and the receive antenna gain of the UAV. The 3D radiation map reconstruction module is used to map the corrected UAV position to a spherical coordinate system centered on the communication base station, and reconstruct the 3D radiation map of the communication base station based on the UAV's relative transmit antenna gain in the spherical coordinate system. The low-altitude continuous coverage assessment module is used to assess the low-altitude airspace radiation coverage capability of a communication base station based on its low-altitude coverage map, and to assess its low-altitude directional radiation coverage capability based on its reconstructed three-dimensional radiation map.
[0070] Example In this embodiment, the test scenario is an open space, the communication base station uses a horn antenna, and the communication frequency is... The signal is 2.4 GHz, the coordinates of the communication base station are (118.725°, 31.756°, 7.9m), the antenna aperture of the communication base station is 0.5m, the gain of the UAV's onboard antenna is 0dB, the UAV's onboard antenna is located 0.5m directly below the GPS antenna, and the ground environment type is concrete.
[0071] The UAV collected radiation characteristic data along a uniform circular trajectory around the communication base station with an actual flight radius of 15m, and recorded the corresponding UAV position information and pose. Some of the collected data are shown in Table 1.
[0072] Table 1: Data collected by UAV
[0073] The drone's position information is corrected based on its pose, GPS antenna installation location, and airborne antenna installation location to obtain the corrected drone position. Some of the corrected drone positions are shown in Table 2.
[0074] Table 2: Corrected UAV Locations
[0075] A noisy covariance matrix is constructed based on the corrected UAV location, and a low-altitude coverage map of the communication base station is reconstructed by combining it with the collected radiation characteristic data, such as... Figure 2 As shown, five altitude slices are used for illustration: 5m, 10m, 15m, 20m, and 25m. The horizontal axis represents longitude and latitude, and the color bars represent received power intensity in dBm, ranging from approximately -110dBm to -50dBm. Lighter colors indicate stronger signals and better coverage, while darker colors indicate weaker signals and potential blind spots. It can be seen that the closer to the central base station, the stronger the signal and the better the coverage. The coverage distribution at different altitudes maintains a certain spatial consistency overall, while there are regional differences in local enhancement or attenuation with altitude, reflecting the continuity and high correlation of base station coverage in low-altitude airspace.
[0076] The relative transmit antenna gain of the UAV is calculated based on the corrected UAV location, the location of the communication base station, and the receive antenna gain of the UAV. The relative transmit antenna gains corresponding to some of the corrected acquisition locations are shown in Table 3.
[0077] Table 3: Relative Transmitting Antenna Gain of UAVs
[0078] The corrected UAV position was mapped to a spherical coordinate system centered on the communication base station, and the UAV's relative transmit antenna gain was mapped to the corresponding position in the spherical coordinate system. The mapping results are shown in Table 4.
[0079] Table 4: Relative transmit antenna gain of UAV mapped to corresponding positions in spherical coordinate system
[0080] The three-dimensional radiation map of the communication base station is reconstructed based on the relative transmit antenna gain of the UAV in the spherical coordinate system, such as... Figure 3-4 Finally, the E-plane and H-plane radiation maps of the communication base station, as well as the complete three-dimensional radiation map, were obtained. Figure 5 As shown in the diagram, the E-plane radiation pattern reveals a distinct main lobe structure in the horizontal plane. The main radiated energy is concentrated within a specific azimuth range, and the radiation intensity rapidly decreases as the angle deviates from the main lobe direction. The sidelobe amplitudes are generally low, indicating good directivity in the vertical direction, which is beneficial for effective low-altitude airspace coverage. The H-plane radiation pattern reflects the antenna's radiation distribution characteristics in the vertical direction, exhibiting relatively continuous angular coverage while showing some gain fluctuations. The three-dimensional radiation pattern comprehensively displays the antenna's radiation distribution across the entire angular domain, allowing for a direct observation of the positional relationships between the main radiation direction, energy concentration areas, and weak radiation areas in three-dimensional space.
[0081] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of the present invention should be considered within the scope of protection of the present invention.
Claims
1. A method for testing the performance of low-altitude continuous coverage based on a communication base station, characterized in that, Comprising the following steps: Step S1: the unmanned aerial vehicle flies around the communication base station according to the preset trajectory, collects the radiation characteristic data, and records the position information and pose of the unmanned aerial vehicle during the collection of the radiation characteristic data; Step S2: correcting the position information of the unmanned aerial vehicle according to the pose of the unmanned aerial vehicle, the installation position of the GPS antenna and the installation position of the airborne antenna, to obtain the corrected position of the unmanned aerial vehicle; Step S3: constructing a noise covariance matrix according to the corrected position of the unmanned aerial vehicle, and reconstructing a low-altitude coverage map of the communication base station in combination with the collected radiation characteristic data; Step S4: determining a low-altitude continuous coverage area according to the low-altitude coverage map of the communication base station, and evaluating the low-altitude airspace radiation coverage capability of the communication base station; Step S5: calculating the relative transmitting antenna gain of the unmanned aerial vehicle according to the corrected position of the unmanned aerial vehicle, the position of the communication base station and the receiving antenna gain of the unmanned aerial vehicle; Step S6: mapping the corrected position of the unmanned aerial vehicle to a spherical coordinate system with the communication base station as the center, and mapping the relative transmitting antenna gain of the unmanned aerial vehicle to the corresponding position of the spherical coordinate system; Step S7: reconstructing a three-dimensional radiation map of the communication base station according to the relative transmitting antenna gain of the unmanned aerial vehicle in the spherical coordinate system; Step S8: determining a continuous coverage area in the low-altitude direction according to the reconstructed three-dimensional radiation map of the communication base station, and evaluating the low-altitude direction radiation coverage capability of the communication base station. 2.The method of claim 1, wherein, According to the communication frequency of the communication base station and the antenna aperture of the communication base station Determining a minimum radius of a preset trajectory : wherein denotes the speed of light. 3.The method of claim 1, wherein, Step S2 comprises the following sub-steps: Step S2.1: converting the position information of the UAV in the terrestrial coordinate system into the position of the UAV in the geocentric spatial coordinate system Step S2.1: converting the position information of the UAV in the terrestrial coordinate system into the position of the UAV in the geocentric spatial coordinate system : wherein, denotes the longitude, the latitude and the altitude of the UAV at the first collection point, denotes the meridian curvature radius of the UAV at the second collection point, , denotes the major semi-axis of the Earth ellipsoid, denotes the first eccentricity of the Earth ellipsoid, , denotes the minor semi-axis of the Earth ellipsoid; Step S2.2: Calculate the position of the UAV in the geocentric spatial coordinate system According to the relative position of the GPS antenna installation position and the on-board antenna installation position of the UAV Calculate the position of the UAV after the translation transformation : ； Step S2.3: calculating a rotation matrix based on the pose of the drone computing a rotation matrix : wherein, respectively represent the roll angle, the pitch angle and the yaw angle of the UAV at the i-th collection point, respectively represent the roll angle, the pitch angle and the yaw angle of the UAV at the i-th collection point, respectively represent the rotation matrix of the UAV at the i-th collection point about the x-axis, respectively represent the rotation matrix of the UAV at the i-th collection point about the x-axis, respectively represent the rotation matrix of the UAV at the i-th collection point about the x-axis, respectively represent the rotation matrix of the UAV at the i-th collection point about the x-axis, respectively represent the rotation matrix of the UAV at the i-th collection point about the x-axis, ; Step S2.4: Translating the transformed UAV position with a rotation matrix The correction is made to obtain a corrected UAV position : 。 4. The method of claim 1, wherein the method further comprises: Step S3 comprises the following sub-steps: Step S3.1: composing a known position matrix from all corrected drone positions composing a known radiation matrix from all collected radiation characteristic data wherein denotes the number of collection points, denotes the drone position corrected for the collection point, , the radiation characteristic data collected by the drone at the collection point; Step S3.2: Compute the covariance matrix between the acquisition points from the known position matrix and add noise, construct the noisy covariance matrix : wherein denotes the covariance matrix of the noise; Step S3.3: Grouping the non-collected drone positions into a non-collected position matrix calculating a covariance matrix of the non-collected position matrix and the known position matrix calculating a non-collected radiation matrix in combination with the covariance matrix with noise and the known radiation matrix: Step S3.4: the known radiation matrix and the uncollected radiation matrix are jointly composed into a low-altitude coverage map of the communication base station.
5. The method for testing the low-altitude continuous coverage performance of a communication base station according to claim 1, wherein, Step S4 comprises the following sub-steps: Step S4.1: setting a spatial coverage threshold, setting the area with radiation characteristic data lower than the spatial coverage threshold in the low-altitude coverage map of the communication base station to 0, and setting the remaining area to 1; Step S4.2: Perform three-dimensional connected domain analysis on all regions with value 1 to obtain the maximum connected radiation coverage region, and calculate the low-altitude airspace radiation coverage capability of the communication base station : wherein, represents the area of the maximum connected radiation footprint, represents the area of the evaluation region of the low-altitude coverage map of the communication base station.
6. The method for testing the low-altitude continuous coverage performance of a communication base station according to claim 1, wherein, Step S5 comprises the following sub-steps: Step S5.1: converting the position of the communication base station in the terrestrial coordinate system into a position of the communication base station in the geocentric space coordinate system Step S5.2: converting the position of the communication base station in the geocentric space coordinate system into a position of the communication base station in the geodetic coordinate system Step S5.3: correcting the position of the unmanned aerial vehicle in the geodetic coordinate system in combination with the acquisition point Step S5.4: determining the position of the reflection point corresponding to each acquisition point Step S5.5: determining the position of the reflection point corresponding to each acquisition point wherein, denotes the longitude, latitude and altitude of a communication base station, denotes the length semi-axis of the Earth ellipsoid, denotes the short semi-axis of the Earth ellipsoid; Step S5.2: drone position corrected with acquisition point , corresponding reflection point position and communication base station position in geocentric space coordinate system , respectively calculate the distance between acquisition point and communication base station , the distance between acquisition point and reflection point and the distance between reflection point and communication base station , determine the distance difference , phase difference and the included angle formed by acquisition point, reflection point and communication base station : wherein denotes a communication frequency of a communication base station, denotes the speed of light; Step S5.3: determining the relative permittivity according to the terrestrial environment of the communication base station , in combination with the angle formed by the collection point, the reflection point and the communication base station calculating the polarization coefficient and the reflection coefficient : wherein represents a vertical polarization coefficient, , represents a horizontal polarization coefficient, ; Step S5.4: Calculate the transmitting antenna gain of the drone based on the receiving antenna gain of the drone in combination with the reflection coefficient and the phase difference : wherein, denotes the transmit power of the drone, denotes the receive power of the drone; Step S5.5: calculating the relative transmission antenna gain of the drone as a function of the transmission antenna gain of the drone and the maximum transmission antenna gain : 。 7. The method of claim 1, wherein the low-altitude continuous coverage performance test method based on a communication base station is characterized by, The process of mapping the corrected position of the unmanned aerial vehicle to the spherical coordinate system with the communication base station as the center in step S6 is: wherein, represents a position of a communication base station in a geocentric spatial coordinate system, represents a corrected position of the unmanned aerial vehicle, represents a distance between a collection point and the communication base station, represents a polar angle corresponding to the unmanned aerial vehicle at the th collection point, represents an azimuth angle corresponding to the unmanned aerial vehicle at the th collection point. 8.The method of claim 1, wherein, Step S7 comprises the following sub-steps: Step S7.1: According to the position of the collection point of the unmanned aerial vehicle in the spherical coordinate system, the distance between the collection point and the non-collection point is calculated : wherein, denotes the polar and azimuthal angles of the unmanned aerial vehicle at the first collection point, denotes the polar and azimuthal angles of the unmanned aerial vehicle at the second collection point, denotes the spherical arc length; Step S7.2: According to , the communication frequency of the communication base station , the position height of the aerial antenna of the UAV calculating the path loss : wherein and is a propagation environment dependent correction parameter, is a shadow fading factor; Step S7.3: According to path loss Computing weights wherein, denotes the number of collection points; Step S7.4: calculating the weight The relative transmitting antenna gain of the uncollected point is calculated in combination with the relative transmitting antenna gain of the UAV sampling point in the spherical coordinate system : wherein, represents the relative gain of the UAV sampling point to the transmitting antenna in the spherical coordinate system; Step S7.5: repeating steps S7.1-S7.4 until the relative transmitting antenna gain of all uncollected points is obtained, and the relative transmitting antenna gain of the unmanned aerial vehicle in the spherical coordinate system and the relative transmitting antenna gain of all uncollected points are jointly composed into a three-dimensional radiation map of the communication base station.
9. The method of claim 1, wherein the low-altitude continuous coverage performance test method based on a communication base station is characterized by, Step S8 comprises the following sub-steps: Step S8.1: setting a direction coverage threshold, setting the area with relative transmitting antenna gain lower than the direction coverage threshold in the three-dimensional radiation map of the communication base station to 0, and setting the remaining area to 1; Step S8.2: Perform three-dimensional connected component analysis on all regions with value 1 to obtain the largest connected radiation coverage region, and calculate the low-altitude direction radiation coverage capability of the communication base station : wherein, represents the area of the maximum connected radiation coverage, represents the area of the evaluation region of the three-dimensional radiation pattern of the communication base station.
10. A low-altitude continuous coverage performance test system based on a communication base station, characterized in that, Comprising: a data collection module, a spatial position correction module, a low-altitude coverage map reconstruction module, a transmitting gain calculation module, a three-dimensional radiation map reconstruction module and a low-altitude continuous coverage evaluation module; The data collection module is used to collect radiation characteristic data by the unmanned aerial vehicle, and collect the position information and pose of the unmanned aerial vehicle during the collection of the radiation characteristic data; The spatial position correction module is used to correct the position information of the unmanned aerial vehicle according to the pose of the unmanned aerial vehicle, the installation position of the GPS antenna and the installation position of the airborne antenna, to obtain the corrected position of the unmanned aerial vehicle; The low-altitude coverage map reconstruction module is used to construct a noise covariance matrix according to the corrected position of the unmanned aerial vehicle, and reconstruct a low-altitude coverage map of the communication base station in combination with the collected radiation characteristic data; The transmit gain calculation module is used to calculate the relative transmit antenna gain of the UAV based on the corrected UAV position, the position of the communication base station, and the receive antenna gain of the UAV. The three-dimensional radiation map reconstruction module is used to map the corrected UAV position to a spherical coordinate system centered on the communication base station, and reconstruct the three-dimensional radiation map of the communication base station based on the relative transmit antenna gain of the UAV in the spherical coordinate system. The low-altitude continuous coverage assessment module is used to assess the low-altitude airspace radiation coverage capability of the communication base station based on the low-altitude coverage map of the communication base station, and to assess the low-altitude directional radiation coverage capability of the communication base station based on the reconstructed three-dimensional radiation map of the communication base station.