OTA performance test method and system of unmanned aerial vehicle antenna

Abstract

The invention discloses an OTA performance test method and system for an antenna of an unmanned aerial vehicle, relates to the technical field of unmanned aerial vehicle testing, and solves the technical problem that the OTA performance of the antenna of the unmanned aerial vehicle is difficult to accurately test. The method comprises the steps that a simulation base station is placed above a tested unmanned aerial vehicle, and the tested unmanned aerial vehicle is in a ground take-off state; rotating the controllable rotating table for multiple times at a first pitch angle and / or a preset azimuth angle to obtain multiple groups of equivalent omnidirectional radiation power values EIRP, and calculating a circumferential total radiation power value CTRP and a power coverage rate in a ground takeoff state; the simulation base station is placed below the tested unmanned aerial vehicle, and the tested unmanned aerial vehicle is in an air flight state; and rotating the controllable rotating table for multiple times at a second pitch angle and / or a preset azimuth angle to obtain a plurality of groups of equivalent omnidirectional radiation power values EIRP, and calculating a circumferential total radiation power value CTRP and a power coverage rate in an air flight state. The antenna OTA performance of the unmanned aerial vehicle in the ground take-off state and the high-altitude flight state is tested, and the antenna OTA performance can be obtained more accurately.

Description

Technical Field

[0001] The present invention relates to the technical field of unmanned aerial vehicle testing, and in particular to an OTA performance testing method and system for an unmanned aerial vehicle antenna. Background Art

[0002] With the development of low-altitude economy, the drone market is getting bigger and bigger. The communication performance of drones is an important performance indicator of drones, which directly determines the connection stability of drones during flight. Therefore, it is necessary to test the OTA (Total Radiated Power) performance of drone antennas to obtain the communication performance of drone antennas.

[0003] The existing UAV antenna OTA performance test usually does not explain the state of the UAV power system during the test, and mainly tests the passive performance of the antenna such as gain, radiation pattern, isolation, etc., without distinguishing the antenna performance of the UAV in different states. In fact, the evaluation method of the UAV antenna performance when taking off from the ground and flying in the sky is obviously different. Due to the different locations of the base stations, the evaluation method of the UAV antenna performance is also different, so it is difficult to obtain accurate UAV communication performance parameters with existing testing methods.

[0004] In the process of implementing the present invention, the inventors found that there are at least the following problems in the prior art: The OTA performance test method of drone antennas is difficult to accurately test the communication performance of drones and is difficult to meet actual usage needs. Summary of the invention

[0005] The purpose of the present invention is to provide an OTA performance test method and system for a drone antenna, so as to solve the technical problem that the existing drone antenna OTA performance test method is difficult to accurately test the communication performance of the drone and is difficult to meet the actual use needs. The preferred technical solutions among the many technical solutions provided by the present invention can produce many technical effects as described below.

[0006] To achieve the above object, the present invention provides the following technical solutions: The present invention provides an OTA performance test method for a drone antenna, comprising the following steps: S100: Place the UAV under test on a controllable rotating table, and make the UAV under test within the quiet area of ​​the darkroom, and use the control host to set the connection parameters of the simulated base station and the comprehensive tester; S200: Place the simulated base station above the horizontal plane of the UAV under test, and communicate with the UAV under test through the OTA coupling of the detection antenna, so that the radiation mode of the UAV under test is in a ground take-off state; S300: Rotate the controllable rotating table multiple times at a first pitch angle and / or a preset azimuth angle, test and obtain the equivalent isotropic radiated power value EIRP of the UAV under multiple groups of pitch angles or azimuth angles, and calculate the circumferential total radiation power value CTRP based on the equivalent isotropic radiated power value EIRP; S400: Based on the power coverage threshold P0, all the equivalent isotropic radiated power values ​​EIRP greater than the power coverage threshold P0 are calculated. Add up the areas and divide by the total area to obtain the power coverage of the UAV under test in the ground take-off state; S500: place the simulated base station below the horizontal plane of the UAV under test, and communicate with the UAV under test through the OTA coupling of the detection antenna, and the radiation mode of the UAV under test is in the air flight state; S600: rotate the controllable rotating table multiple times at a second pitch angle and / or a preset azimuth angle, test and obtain the equivalent isotropic radiated power value EIRP of the UAV under test at multiple groups of pitch angles or azimuth angles, and calculate the circumferential total radiated power value CTRP according to the equivalent isotropic radiated power value EIRP; S700: based on the power coverage rate threshold value P0, add up the areas where all equivalent isotropic radiated power values ​​EIRP are greater than the power coverage rate threshold value P0, and divide by the total area to obtain the power coverage of the UAV under test in the air flight state.

[0007] Preferably, the first pitch angle is 90 degrees to 135 degrees, the second pitch angle is 0 degrees to 90 degrees, and the preset azimuth angle is 360 degrees.

[0008] Preferably, in the steps S300 and S600, the calculation formula of the circumferential total radiation power value CTRP is: in, express The angle of the i-th sampling point on the axis, express The angle of the first sampling point on the axis, express The angle of the Nth sampling point on the axis is the pitch angle; express The angle of the jth sampling point on the axis is the azimuth; M represents The number of sampling points on the axis, N represents The number of sampling points on the axis; Indicates angle hour, The measurement result of the equivalent isotropic radiated power (EIRP) in the axial polarization direction, in dBm. Indicates angle hour, The measurement result of the equivalent isotropic radiated power (EIRP) in the axial polarization direction, in dBm. Indicates angle hour, The measurement result of the equivalent isotropic radiated power (EIRP) in the axial polarization direction, in dBm. Indicates angle hour, The measurement result of the equivalent isotropic radiated power (EIRP) in the axial polarization direction, in dBm. Indicates angle hour, The measurement result of the equivalent isotropic radiated power (EIRP) in the axial polarization direction, in dBm. Indicates angle hour, The measurement result of the equivalent isotropic radiated power (EIRP) in the axial polarization direction, in dBm.

[0009] Preferably, in the steps S400 and S700, the calculation formula of the power coverage ratio R is: in, express The angle of the first sampling point on the axis, express The angle of the Nth sampling point on the axis is the pitch angle; M represents The number of sampling points on the axis, N represents The number of sampling points on the axis; Indicates the value of the equivalent isotropic radiated power (EIRP) when it is greater than the power coverage threshold P0.

[0010] Preferably, in the steps S300 and S600, the controllable rotating table is rotated multiple times in steps of 15 degrees.

[0011] Preferably, when the radiation mode of the UAV under test is in an airborne state, the UAV under test is flexibly fixed on the controllable rotating table.

[0012] An OTA performance test system for an unmanned aerial vehicle antenna is used to run an OTA performance test method for an unmanned aerial vehicle antenna as described in any of the above items, comprising: a darkroom, a control host, a comprehensive tester, a simulated base station, a probe antenna, a controllable rotating table, and a shielding box; the probe antenna, the controllable rotating table, and the shielding box are all located in the darkroom; the controllable rotating table is used to fix the unmanned aerial vehicle under test, and can rotate the unmanned aerial vehicle under test in pitch or azimuth; the comprehensive tester and the simulated base station are both located in the shielding box; the comprehensive tester is used to perform communication tests on the unmanned aerial vehicle under test in all directions, and the simulated base station is used to perform base station simulation and communicate with the unmanned aerial vehicle under test; the control host is communicatively connected to the comprehensive tester and the simulated base station, and is used to set the connection parameters of the comprehensive tester and the simulated base station.

[0013] Preferably, the test system further comprises a power divider or a switching switch, and the comprehensive tester and the analog base station are both connected to the probe antenna via the power divider or the switching switch.

[0014] Preferably, if the number of the probe antenna is one, the controllable rotating table is a 3D rotating table; if the number of the probe antenna is multiple or the probe antenna is a ring antenna, the controllable rotating table is a 2D rotating table or a 3D rotating table.

[0015] Preferably, the walls of the darkroom in all directions are paved with absorbing materials, and the quiet zone is greater than 10 cm.

[0016] Implementing one of the above technical solutions of the present invention has the following advantages or beneficial effects: The test method of the present invention tests the OTA performance of the antenna of the drone in both the ground takeoff state and the high-altitude flight state. It can more accurately obtain the OTA performance of the drone antenna than the existing test method, which is convenient for meeting the actual use needs. At the same time, the controllable rotating table of the power system state of the drone in the antenna performance test experiment is described, and the active performance test method of the drone by detecting the antenna OTA coupling mode is described, which makes the test operation simpler and convenient for testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. It is obvious that the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work. In the drawings: Figure 1 This is a flow chart of an OTA performance test method for a drone antenna according to Embodiment 1 of the present invention; Figure 2is a schematic diagram of an OTA performance test system for a drone antenna according to a second embodiment of the present invention; Figure 3 It is a schematic diagram of the rotation of a controllable rotating table of an OTA performance test system for an unmanned aerial vehicle antenna according to a second embodiment of the present invention. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the present invention clearer, the various exemplary embodiments to be described below will refer to the corresponding drawings, which constitute a part of the exemplary embodiments, wherein various exemplary embodiments that may be used to implement the present invention are described. Unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementation methods described in the following exemplary embodiments do not represent all implementation methods consistent with the present disclosure. It should be understood that they are only examples of processes, methods, devices, etc. that are consistent with some aspects of the present disclosure as detailed in the attached claims, and other embodiments may also be used, or the embodiments listed herein may be modified in structure and function without departing from the scope and essence of the present invention.

[0019] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", etc. indicate the orientation or positional relationship based on the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the elements referred to must have a specific orientation, be constructed and operated in a specific orientation. The terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. The term "multiple" means two or more. The terms "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, an integral connection, a mechanical connection, an electrical connection, a communication connection, a direct connection, an indirect connection through an intermediate medium, and can be the internal connection of two elements or the interaction relationship between two elements. The term "and / or" includes any and all combinations of one or more related listed items. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0020] In order to illustrate the technical solution of the present invention, a specific embodiment is used below for description, and only the parts related to the embodiment of the present invention are shown.

[0021] Embodiment 1: like Figure 1As shown, the present invention provides an OTA (Over The Air) Air, a test for evaluating the performance of a device in a wireless transmission environment) performance test method, comprising the following steps: S100: placing a UAV under test on a controllable rotating table, and making the UAV under test within the quiet area of ​​a darkroom, and using a control host to set the connection parameters of a simulated base station and a comprehensive tester; S200: placing a simulated base station above the horizontal plane of the UAV under test, and communicating with the UAV under test through OTA coupling of a detection antenna, so that the radiation mode of the UAV under test is in a ground take-off state; S300: rotating the controllable rotating table multiple times at a first pitch angle (the pitch angle is the angle between a 5G terminal and the positive semi-axis of the Z axis in a spherical coordinate system) and / or a preset azimuth angle (the azimuth angle is the angle between the projection line of the 5G terminal on the XoY plane in the spherical coordinate system and the positive semi-axis of the X axis in the spherical coordinate system, and the 5G terminal moves left and right in the horizontal plane when the azimuth angle is adjusted), and testing to obtain the equivalent isotropic radiated power values ​​EIRP (Equivalent Isotropic Radiated Power) of the UAV under multiple sets of pitch angles or azimuth angles Power, and calculate the circular total radiated power value CTRP (Circular Total Radiated Power) based on the equivalent isotropic radiated power value EIRP Power); S400: based on the power coverage rate threshold value P0, add up the areas where all equivalent isotropic radiated power values ​​EIRP are greater than the power coverage rate threshold value P0, and divide by the total area to obtain the power coverage rate of the UAV under test in the ground take-off state; S500: place the simulated base station below the horizontal plane of the UAV under test, and communicate with the UAV under test through the OTA coupling of the detection antenna, and the radiation mode of the UAV under test is in the air flight state; S600: rotate the controllable rotating table multiple times at a second pitch angle and / or a preset azimuth angle, test and obtain the equivalent isotropic radiated power values ​​EIRP of the UAV under test at multiple groups of pitch angles or azimuth angles, and calculate the circumferential total radiated power value CTRP according to the equivalent isotropic radiated power value EIRP; S700: based on the power coverage rate threshold value P0, add up the areas where all equivalent isotropic radiated power values ​​EIRP are greater than the power coverage rate threshold value P0, and divide by the total area to obtain the power coverage rate of the UAV under test in the air flight state. This method tests the OTA performance of the drone's antenna in both the ground takeoff state and the high-altitude flight state. It can more accurately obtain the OTA performance of the drone antenna than the existing test method, which is convenient for meeting the actual use needs. At the same time, the controllable rotating table of the power system state of the drone in the antenna performance test experiment is described, and the active performance test method of the drone by detecting the antenna OTA coupling mode is described, making the test operation relatively simple and convenient for testing.

[0022] As an optional implementation, the first pitch angle is 90 to 135 degrees, and this pitch angle range corresponds to the spatial range from horizontal to obliquely upward, thereby realizing the simulation of the ground take-off state; the second pitch angle is 0 to 90 degrees, and this pitch angle range corresponds to the spatial range from directly below to horizontal, thereby realizing the simulation of the UAV's air flight state; the preset azimuth angle is 360 degrees, which is convenient for 360-degree full-directional rotation in the horizontal plane, so as to obtain more comprehensive test results.

[0023] As an optional implementation, in step S300 and step S600, the calculation formula of the circumferential total radiation power value CTRP is: in, express The angle of the i-th sampling point on the axis, express The angle of the first sampling point on the axis, express The angle of the Nth sampling point on the axis is the pitch angle, and the range of the pitch angle is [0, π]; express The angle of the jth sampling point on the axis is the azimuth, and the range of the azimuth is [0, 2π]; M represents The number of sampling points on the axis. It is preferred that the sampling points are evenly arranged, that is, the azimuth angle 2π is divided into M equal parts; N represents The number of sampling points on the axis, preferably the sampling points are evenly distributed, that is, the pitch angle π is divided into N parts; Indicates angle hour, The measurement result of the equivalent isotropic radiated power (EIRP) in the axial polarization direction, in dBm. Indicates angle hour, The measurement result of the equivalent isotropic radiated power (EIRP) in the axial polarization direction, in dBm. Indicates angle hour, The measurement result of the equivalent isotropic radiated power (EIRP) in the axial polarization direction, in dBm. Indicates angle hour, The measurement result of the equivalent isotropic radiated power (EIRP) in the axial polarization direction, in dBm. Indicates angle hour, The measurement result of the equivalent isotropic radiated power (EIRP) in the axial polarization direction, in dBm. Indicates angle hour, The measurement result of the equivalent isotropic radiated power (EIRP) in the axial polarization direction, in dBm.

[0024] As an optional implementation, in step S400 and step S700, the calculation formula of the power coverage ratio R is: in, express The angle of the first sampling point on the axis, express The angle of the Nth sampling point on the axis is the pitch angle; M represents The number of sampling points on the axis, N represents The number of sampling points on the axis; Indicates the value of the equivalent isotropic radiated power (EIRP) when it is greater than the power coverage threshold P0.

[0025] As an optional implementation, in step S300 and step S600, the controllable rotating table is rotated multiple times in 15-degree increments, that is, the first pitch angle, the second pitch angle, and the preset azimuth angle are rotated 15 degrees each time, thereby obtaining a variety of angle combinations for easy testing. Of course, other angles can also be selected to rotate the controllable rotating table in steps according to test needs, such as 10 degrees, 20 degrees, 30 degrees, etc.

[0026] As an optional implementation, when the radiation mode of the UAV under test is in an airborne state, the UAV under test is flexibly fixed on a controllable rotating table, such as being tied to the controllable rotating table by a rope, so that the UAV under test is in a relatively static state in a darkroom when in an airborne state, which is convenient for testing.

[0027] The embodiment is only a specific example and does not represent only one implementation mode of the present invention.

[0028] Embodiment 2: An OTA performance test system for a drone antenna is tested by an OTA performance test method for a drone antenna in Embodiment 1, such as Figure 3As shown, it includes: a darkroom, a control host, a comprehensive tester, a simulated base station, a probe antenna, a controllable rotating table, and a shielding box. The probe antenna, the controllable rotating table, and the shielding box are all located in the darkroom. Compared with the coupling box, the darkroom can make the test environment more closed and clean, thereby avoiding external interference in the test and affecting the accuracy of the test results of the UAV under test. The controllable rotating table is used to fix the UAV under test, and can rotate the pitch angle and / or azimuth angle of the UAV under test (the specific structure and control can be realized by the existing technology), so that the UAV under test can be tested in all directions. The comprehensive tester and the simulated base station are both located in the shielding box, so as to avoid signal interference to the UAV under test. The comprehensive tester is used to perform communication tests on the UAV under test in all directions. It can be used to test various communication indicators in the UAV under test as needed, such as transmission power, receiving sensitivity and other radio frequency indicators. The simulated base station is used to simulate the base station and communicate with the UAV under test to establish a communication scenario for the UAV under test. The control host is connected to the comprehensive tester and the simulated base station in communication, and is used to set the connection parameters of the comprehensive tester and the simulated base station to adapt to the test needs of the UAV under test.

[0029] As an optional implementation, the test system also includes a power divider or a switching switch. The comprehensive tester and the analog base station are connected to the probe antenna through the power divider or the switching switch. The power distribution of the power divider is preferably 1:1. The power divider or the switching switch is also located in a shielding box to avoid interference.

[0030] As an optional implementation, if the number of probe antennas is one, the controllable rotating table is a 3D rotating table, so that the pitch angle or azimuth angle can be changed through the controllable rotating table, and the relative position relationship between the UAV under test and the probe antenna can be adjusted to achieve different directions or angles of different UAVs under test. If the number of probe antennas is multiple or the probe antenna is a ring antenna, the controllable rotating table is a 2D rotating table (in this case, the probe antenna indirectly realizes different azimuths of the UAV under test, and the 2D rotating table can realize the pitch angle to achieve different directions or angles of the UAV under test) or a 3D rotating table.

[0031] As an optional implementation, the walls of the darkroom in all directions are paved with absorbing materials, and the quiet zone is greater than 10 cm, thereby better ensuring that the electromagnetic environment of the darkroom is not disturbed.

[0032] The above description is only the preferred embodiment of the present invention. It is known to those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application belong to the protection scope of the present invention.

Claims

1. A method for OTA performance testing of drone antennas, characterized in that: The following steps are involved: S100: placing the drone under test on a controllable rotating table, and making the drone under test located within the quiet area of ​​the darkroom, and using the control host to set the connection parameters of the simulated base station and the comprehensive tester; S200: placing a simulated base station above the horizontal plane of the drone under test, and communicating with the drone under test by means of OTA coupling of a detection antenna, so that the radiation mode of the drone under test is in a ground take-off state; S300: rotating the controllable rotating platform multiple times at a first pitch angle and / or a preset azimuth angle, testing and obtaining equivalent isotropic radiated power values ​​EIRP of the tested drone at multiple sets of pitch angles or azimuth angles, and calculating a circumferential total radiated power value CTRP according to the equivalent isotropic radiated power value EIRP; S400: Based on the power coverage rate threshold value P0, add up the areas where all equivalent isotropically radiated power values ​​EIRP are greater than the power coverage rate threshold value P0, and divide the sum by the total area to obtain the power coverage rate of the tested UAV in the ground takeoff state; S500: placing a simulated base station below the horizontal plane of the drone under test, and communicating with the drone under test by means of OTA coupling of a detection antenna, wherein the radiation mode of the drone under test is in an airborne flight state; S600: rotating the controllable rotating platform multiple times at a second pitch angle and / or a preset azimuth angle, testing and obtaining equivalent isotropic radiated power values ​​EIRP of the tested drone at multiple sets of pitch angles or azimuth angles, and calculating a circumferential total radiated power value CTRP according to the equivalent isotropic radiated power value EIRP; S700: Based on the power coverage rate threshold value P0, add up the areas where all equivalent isotropically radiated power values ​​EIRP are greater than the power coverage rate threshold value P0, and divide the sum by the total area to obtain the power coverage rate of the tested UAV in the air flight state.

2. The OTA performance test method of a drone antenna according to claim 1, characterized in that: The first pitch angle is 90 degrees to 135 degrees, the second pitch angle is 0 degrees to 90 degrees, and the preset azimuth angle is 360 degrees.

3. The OTA performance test method of a drone antenna according to claim 1, characterized in that: In the steps S300 and S600, the calculation formula of the circumferential total radiation power value CTRP is: in, express The angle of the i-th sampling point on the axis, express The angle of the first sampling point on the axis, express The angle of the Nth sampling point on the axis is the pitch angle; express The angle of the jth sampling point on the axis is the azimuth; M represents The number of sampling points on the axis, N represents The number of sampling points on the axis; Indicates angle hour, The measurement result of the equivalent isotropic radiated power (EIRP) in the axial polarization direction, in dBm. Indicates angle hour, The measurement result of the equivalent isotropic radiated power (EIRP) in the axial polarization direction, in dBm. Indicates angle hour, The measurement result of the equivalent isotropic radiated power (EIRP) in the axial polarization direction, in dBm. Indicates angle hour, The measurement result of the equivalent isotropic radiated power (EIRP) in the axial polarization direction, in dBm. Indicates angle hour, The measurement result of the equivalent isotropic radiated power (EIRP) in the axial polarization direction, in dBm. Indicates angle hour, The measurement result of the equivalent isotropic radiated power (EIRP) in the axial polarization direction, in dBm.

4. The OTA performance test method of a drone antenna according to claim 1, characterized in that: In the steps S400 and S700, the calculation formula of the power coverage ratio R is: in, express The angle of the first sampling point on the axis, express The angle of the Nth sampling point on the axis is the pitch angle; M represents The number of sampling points on the axis, N represents The number of sampling points on the axis; Indicates the value of the equivalent isotropic radiated power (EIRP) when it is greater than the power coverage threshold P0.

5. The OTA performance test method of a drone antenna according to claim 1, characterized in that: In the steps S300 and S600, the controllable rotating table is rotated multiple times in steps of 15 degrees.

6. The OTA performance test method of a drone antenna according to claim 1, characterized in that: When the radiation mode of the tested UAV is in an air-flying state, the tested UAV is flexibly fixed on the controllable rotating platform.

7. An OTA performance test system for drone antennas, characterized in that: An OTA performance test method for an unmanned aerial vehicle antenna used to run any one of claims 1-6, comprising: a darkroom, a control host, a comprehensive tester, a simulated base station, a probe antenna, a controllable rotating table, and a shielding box; the probe antenna, the controllable rotating table, and the shielding box are all located in the darkroom; the controllable rotating table is used to fix the unmanned aerial vehicle under test, and can rotate the unmanned aerial vehicle under test in pitch or azimuth; the comprehensive tester and the simulated base station are both located in the shielding box; the comprehensive tester is used to perform communication tests on the unmanned aerial vehicle under test in all directions, and the simulated base station is used to perform base station simulation and communicate with the unmanned aerial vehicle under test; the control host is communicatively connected to the comprehensive tester and the simulated base station, and is used to set the connection parameters of the comprehensive tester and the simulated base station.

8. The OTA performance test system for a drone antenna according to claim 7, characterized in that: The test system further comprises a power divider or a switching switch, and the comprehensive tester and the analog base station are both connected to the probe antenna via the power divider or the switching switch.

9. The OTA performance test system for a drone antenna according to claim 7, characterized in that: If the number of the probe antenna is one, the controllable rotating table is a 3D rotating table; if the number of the probe antenna is multiple or the probe antenna is a ring antenna, the controllable rotating table is a 2D rotating table or a 3D rotating table.

10. The OTA performance test system for drone antenna according to claim 7, characterized in that: The walls of the darkroom in all directions are paved with wave-absorbing materials, and the quiet zone is greater than 10 cm.

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