Method and device for testing air interface performance of ground terminal of low-orbit satellite

Abstract

The invention provides a low-orbit satellite ground terminal air interface performance test method and device, and the method comprises the steps: calculating satellite position data observed by a to-be-tested ground terminal at different moments according to a preset ground terminal position and low-orbit communication satellite ephemeris data, and generating a visible satellite motion track of the ground terminal position; selecting a preset number of track points on the visible satellite motion track as test points, and importing satellite position data of the test points into a test system; when the measurement antenna moves to the first test point, satellite position data corresponding to the first test point is transmitted back to the ground terminal to be tested; the to-be-tested ground terminal generates wave beams according to the received satellite position data, connection is established, and the test system completes air interface wireless performance measurement of the first test point; all the test points are traversed through the processing process, air interface wireless performance measurement of the ground terminal to be tested is completed, and air interface wireless performance measurement results corresponding to all the test points are obtained.

Description

Technical Field

[0001] The present invention relates to the field of communication testing technology, and in particular to a method and device for testing air interface performance of a low-orbit satellite ground terminal. Background Art

[0002] This section is intended to provide a background or context for embodiments of the present invention. No description herein is admitted to be prior art by virtue of its inclusion in this section.

[0003] In the development of wireless communication technology, satellite communication is considered a key future direction. Satellite communication refers to communications between ground-based wireless communication devices using satellites as relays. Satellite communication systems consist of satellites and ground components. Satellite communication features a wide communication range; communication is possible within the coverage area of the satellite beam; and it is not susceptible to terrestrial environmental influences or disasters. Satellite communication can effectively supplement existing terrestrial wireless cellular mobile communications.

[0004] Satellite communication systems are divided into high-orbit satellite communication systems and low-orbit satellite communication systems. For traditional high-orbit satellite communication systems (usually referring to geosynchronous orbit satellite communication systems), geosynchronous orbit satellites are usually used as relays. Three geosynchronous orbit satellites can achieve global coverage without the need for satellite switching. For low-orbit satellite communication systems, the surface of the earth is usually covered by thousands to tens of thousands of satellites deployed on several orbital planes, thus forming a cross-linked mesh network. Compared with high-orbit satellite communication systems, low-orbit satellite communication systems have the advantages of high network reliability and flexibility, low transmission delay, low path loss, large communication capacity, weak dependence on ground networks, more efficient frequency reuse and stronger global coverage capabilities. In low-orbit satellite communication systems, the high-speed movement characteristics of satellites cause the satellite-to-ground link topology to exhibit dynamic time-varying characteristics, and the effective communication window between ground terminals and single satellites is usually only a few minutes. In particular, mega-constellation systems employing low orbital altitudes (500-1200 km) and high-belief angles (25°-40°) can achieve sub-satellite trajectory speeds of up to 7.8 km / s, further reducing single-service durations to 2-3 minutes and significantly increasing the frequency of inter-satellite handoffs (approximately 10-20 times per hour). This high frequency of handoffs places a demand on ground terminals for real-time beam redirection. Traditional mechanical scanning antennas, constrained by physical moment of inertia (response time > 1 second), are unable to meet this requirement. Phased array systems must be employed, using electronic scanning to achieve nanosecond beam switching (typical value < 100μs) and dynamic beamforming (beam pointing accuracy < 0.1°). In this context, accurate measurement of the dynamic beam characteristics of phased array equipment is of critical significance: it is necessary to verify its core indicators such as beam pointing accuracy, sidelobe suppression ratio (>20dB), and gain fluctuation (<1dB) during dynamic scanning to ensure stable tracking when the satellite passes over the top quickly (angular velocity reaches 1-3° / s). At the same time, it is necessary to evaluate the multi-beam coordination (number of concurrent beams ≥4) and fast switching (switching time <10ms) capabilities, which play a decisive role in ensuring the availability of the communication link (target >99.9%) and reducing the switching packet loss rate (<0.1%).

[0005] In the over-the-air (OTA) performance testing of phased array equipment for low-orbit satellite ground terminals, the traditional method uses a spherical multi-probe test system to simulate satellite motion scenarios. This system constructs a spherically distributed multi-probe array in a microwave anechoic chamber (a typical configuration includes 64-256 dual-polarization probes, covering EIRP ≥ 50dBm and a frequency range of 0.4-40GHz), and combines it with a channel emulator to generate real-time dynamic spatial channel characteristics. During the test, the phase / amplitude weights of each probe's RF link are precisely controlled (phase resolution ≤ 0.1°, amplitude adjustment step ≤ 0.1dB) to reconstruct the spatial electromagnetic field distribution of the satellite during its on-orbit motion and simulate the following key scenarios:

[0006] High-speed angular motion: Calculate the satellite's apparent angular velocity (typically 1.2-2.8° / s) based on the target orbit altitude (e.g., 550km) and the terminal communication elevation angle (e.g., 25°-40°). Continuous beam pointing is achieved through real-time updates of the probe weight sequence.

[0007] Multi-satellite switching: Based on the constellation configuration (such as Walker Delta) and the terminal field of view (usually set to 120° azimuth × 90° pitch), dynamically activate probe subsets in different spatial orientations to simulate beam switching under multi-satellite visibility conditions (switching interval ≤ 10ms).

[0008] In this dynamic electromagnetic environment, the following core indicators can be verified: beam agility, tracking accuracy (beam pointing accuracy under dynamic scanning) and resistance to switching loss (bit error rate / throughput decrease during satellite switching).

[0009] In summary, this solution uses a spherical multi-probe system to dynamically simulate high-speed satellite motion, multi-satellite switching, and interference environments. Combined with high-precision beam parameter quantization and three-dimensional continuous scanning capabilities, it overcomes the physical limitations of traditional mechanical testing and can fully verify the real-time tracking and anti-switching performance of phased array terminals in complex low-orbit constellation scenarios. However, this solution relies on an extremely complex large-scale spherical multi-probe system and a high-specification microwave anechoic chamber (with a single construction cost exceeding tens of millions of US dollars). This, combined with the regular calibration and maintenance of precision probes (with an average annual cost of approximately one million US dollars) and the computing power required for dynamic channel simulation (requiring a GPU acceleration cluster), has led to an order of magnitude increase in overall testing costs, creating a key bottleneck restricting technology verification and industrialization.

[0010] Therefore, there is an urgent need for a technical solution that can overcome the above-mentioned defects, reduce testing costs and improve testing results. Summary of the Invention

[0011] To address the challenges of existing technologies, this paper proposes a method and apparatus for testing the air interface performance of low-orbit satellite ground terminals. This method enables dynamic multi-beam performance measurement of phased array equipment in a single-probe anechoic chamber, reducing test system construction, maintenance, and testing costs while improving test efficiency.

[0012] In a first aspect of an embodiment of the present invention, a method for testing air interface performance of a low-orbit satellite ground terminal is proposed, comprising:

[0013] Based on the preset ground terminal position and low-orbit communication satellite ephemeris data, the satellite position data observed by the ground terminal to be tested at different times are calculated, and the visible satellite motion trajectory of the ground terminal position is generated;

[0014] Selecting a preset number of trajectory points on the visible satellite motion trajectory as test points, and importing satellite position data of the test points into a test system;

[0015] When the measuring antenna moves to the first test point, the satellite position data corresponding to the first test point is transmitted back to the ground terminal to be tested;

[0016] The ground terminal to be tested generates a beam according to the received satellite position data and establishes a connection, and the test system completes the air interface wireless performance measurement of the first test point;

[0017] Through the above processing, all test points are traversed to complete the air interface wireless performance measurement of the ground terminal to be tested, and the air interface wireless performance measurement results corresponding to all test points are obtained.

[0018] In a second aspect of an embodiment of the present invention, a low-orbit satellite ground terminal air interface performance test device is proposed, comprising:

[0019] A calculation module is used to calculate the satellite position data observed by the ground terminal to be tested at different times based on the preset ground terminal position and low-orbit communication satellite ephemeris data, and generate the visible satellite motion trajectory of the ground terminal position;

[0020] An import module is used to select a preset number of trajectory points on the visible satellite motion trajectory as test points, and import the satellite position data of the test points into the test system;

[0021] A return module is used to return the satellite position data corresponding to the first test point to the ground terminal to be tested when the measurement antenna moves to the first test point;

[0022] The ground terminal to be tested generates a beam according to the received satellite position data and establishes a connection, and the test system completes the air interface wireless performance measurement of the first test point;

[0023] Through the above processing, all test points are traversed to complete the air interface wireless performance measurement of the ground terminal to be tested, and the air interface wireless performance measurement results corresponding to all test points are obtained.

[0024] In a third aspect of an embodiment of the present invention, a computer device is proposed, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements a method for testing the air interface performance of a low-orbit satellite ground terminal when executing the computer program.

[0025] In a fourth aspect of an embodiment of the present invention, a computer-readable storage medium is proposed, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, a method for testing the air interface performance of a low-orbit satellite ground terminal is implemented.

[0026] In a fifth aspect of an embodiment of the present invention, a computer program product is proposed. The computer program product includes a computer program. When the computer program is executed by a processor, a method for testing the air interface performance of a low-orbit satellite ground terminal is implemented.

[0027] The low-orbit satellite ground terminal air interface performance test method and device proposed in the present invention maps the actual motion trajectory of the target low-orbit communication satellite into a series of continuous / discrete measurement antenna positions, simulating satellite motion scenarios by measuring continuous / discrete changes in antenna positions. The test system then sends pre-set target satellite position data to the device under test in real time, replacing the traditional process in which the device under test calculates the relative position of the ground terminal under test and the target satellite in real time based on the received target satellite ephemeris and its own precise position. Compared to the actual operating process of ground satellite terminal phased array equipment in low-orbit satellite communication scenarios, and compared to traditional test solutions that use multi-probe spherical array test systems to simulate satellite motion scenarios, the present invention can complete dynamic multi-beam performance measurements of low-orbit satellite ground terminal phased array equipment in a single-probe darkroom, achieving test accuracy and principle equivalence essentially equivalent to traditional test solutions. This significantly reduces the complexity of the test system, as well as the construction, maintenance, and testing costs of the test system, providing strong technical support for air interface performance testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0029] Figure 1 The present invention is a flowchart of a method for testing the air interface performance of a low-orbit satellite ground terminal according to an embodiment of the present invention.

[0030] Figure 2 FIG. 4 is a schematic diagram of a processing flow for calculating satellite position data according to an embodiment of the present invention.

[0031] Figure 3 FIG. 4 is a schematic diagram of a set of satellite position data according to an embodiment of the present invention.

[0032] Figure 4 The figure is a schematic diagram of a processing flow of dynamic beam tracking of a target satellite according to an embodiment of the present invention.

[0033] Figure 5 The figure is a schematic diagram of the architecture of a low-orbit satellite ground terminal air interface performance test device according to an embodiment of the present invention.

[0034] Figure 6 It is a schematic diagram of the structure of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0035] The principles and spirit of the present invention will be described below with reference to several exemplary embodiments. It should be understood that these embodiments are provided solely to enable those skilled in the art to better understand and implement the present invention, and are not intended to limit the scope of the present invention in any way. Rather, these embodiments are provided to make this disclosure more thorough and complete, and to fully convey the scope of the present disclosure to those skilled in the art.

[0036] Those skilled in the art will appreciate that the embodiments of the present invention may be implemented as a system, apparatus, device, method, or computer program product. Therefore, the present disclosure may be implemented in the following forms: entirely in hardware, entirely in software (including firmware, resident software, microcode, etc.), or in a combination of hardware and software.

[0037] According to an embodiment of the present invention, a method and apparatus for testing the air interface performance of a low-orbit satellite ground terminal are proposed, relating to the field of communication testing technology.

[0038] The principles and spirit of the present invention are explained in detail below with reference to several representative embodiments of the present invention.

[0039] Figure 1 FIG. 1 is a flow chart of a method for testing the air interface performance of a low-orbit satellite ground terminal according to an embodiment of the present invention. Figure 1 As shown, the method includes:

[0040] S101, calculating satellite position data observed by the ground terminal to be measured at different times based on a preset ground terminal position and low-orbit communication satellite ephemeris data, and generating visible satellite motion trajectories at the ground terminal position;

[0041] S102, selecting a preset number of trajectory points on the visible satellite motion trajectory as test points, and importing satellite position data of the test points into a test system;

[0042] S103, when the measuring antenna moves to the first test point, the satellite position data corresponding to the first test point is transmitted back to the ground terminal to be measured;

[0043] S104: The ground terminal to be tested generates a beam according to the received satellite position data and establishes a connection, and the test system completes the air interface wireless performance measurement of the first test point;

[0044] Through the above processing, all test points are traversed to complete the air interface wireless performance measurement of the ground terminal to be tested, and the air interface wireless performance measurement results corresponding to all test points are obtained.

[0045] The low-orbit satellite ground terminal air interface performance test method and device proposed in the present invention maps the actual motion trajectory of the target low-orbit communication satellite into a series of continuous / discrete measurement antenna positions, simulating satellite motion scenarios by measuring continuous / discrete changes in antenna positions. The test system then sends pre-set target satellite position data to the device under test in real time, replacing the traditional process in which the device under test calculates the relative position of the ground terminal under test and the target satellite in real time based on the received target satellite ephemeris and its own precise position. Compared to the actual operating process of ground satellite terminal phased array equipment in low-orbit satellite communication scenarios, and compared to traditional test solutions that use multi-probe spherical array test systems to simulate satellite motion scenarios, the present invention can complete dynamic multi-beam performance measurements of low-orbit satellite ground terminal phased array equipment in a single-probe darkroom, achieving test accuracy and principle equivalence essentially equivalent to traditional test solutions. This significantly reduces the complexity of the test system, as well as the construction, maintenance, and testing costs of the test system, providing strong technical support for air interface performance testing.

[0046] In order to explain the above-mentioned low-orbit satellite ground terminal air interface performance test method more clearly, each step is described in detail below.

[0047] In one embodiment, for S101, based on the preset ground terminal position and low-orbit communication satellite ephemeris data, the satellite position data observed by the ground terminal at different times are calculated, and the visible satellite motion trajectory of the ground terminal position is generated. Figure 2 The specific process includes:

[0048] S201, calculating the visibility start time, end time, and duration of each visibility of the target satellite relative to a preset ground terminal to be measured within a preset simulation cycle according to a preset communication elevation angle range;

[0049] S202, calculating the pitch angle, azimuth angle and slant range of the target satellite relative to the ground terminal to be measured at different measurement times in each visibility time period according to the visibility start time, end time and duration of each visibility.

[0050] refer to Figure 3 , is a schematic diagram of a set of satellite position data according to an embodiment of the present invention. Figure 3 In the chart, the first column is time, the second column is azimuth, the third column is elevation, and the fourth column is slant range.

[0051] Further references Figure 2 , the method further comprises:

[0052] S203, determining a visible satellite motion trajectory based on the slant range, azimuth, and pitch angle of the target satellite relative to a preset ground terminal to be measured at different measurement times during the visible time period; the visible satellite motion trajectory reflects the change in the position of the target satellite over time during the visible time period;

[0053] Specifically, the curve corresponding to the visible satellite motion trajectory mainly reflects the changes in the slant range, azimuth, and pitch angle of the target satellite over time during the visible time period.

[0054] The slant range is the real-time distance between the target satellite and the ground terminal to be measured, which is obtained by normalizing the maximum value of the slant range on the visible target satellite motion trajectory.

[0055] In one embodiment, the satellite position data further includes a real-time gain correction factor for the target satellite antenna beam;

[0056] For different measurement moments within each visible time period, calculate the pitch angle and azimuth angle of the preset ground terminal to be measured relative to the target satellite, and calculate the corresponding real-time gain correction coefficient according to one of the following methods:

[0057] K(θ)=cos n (θ);

[0058] Where K(θ) represents the real-time gain correction coefficient; θ is the preset pitch angle of the ground terminal to be measured relative to the target satellite; n is the pattern factor, which depends on the shape of the antenna pattern. Among them, θ HPBW is the half-power beamwidth of the target satellite antenna in the elevation direction;

[0059] K(θ)=sinc n (θ);

[0060] Where K(θ) represents the real-time gain correction coefficient; θ is the preset pitch angle of the ground terminal to be measured relative to the target satellite; n is the pattern factor, which depends on the shape of the antenna pattern. Among them, θ HPBW is the half-power beamwidth of the target satellite antenna in the elevation direction;

[0061] K(θ, φ)=cos n1 (θ)·sin n2 (φ);

[0062] Wherein, K(θ, φ) represents the real-time gain correction coefficient; θ is the preset pitch angle of the ground terminal to be measured relative to the target satellite; φ is the preset azimuth angle of the ground terminal to be measured relative to the target satellite; θ HPBW ,φHPBW are the half-power beamwidths in the elevation and azimuth directions of the target satellite antenna, respectively.

[0063] In one embodiment, for S102 , a preset number of trajectory points are selected on the visible satellite motion trajectory as test points, and the satellite position data of the test points are imported into a test system.

[0064] Specifically, when selecting test points, the specific process is as follows:

[0065] A series of measurement positions are generated according to the imported satellite position data; during the test process, the test system controls the measurement antenna to move to each measurement position one by one, and completes the air interface wireless performance measurement of the ground terminal under test at the corresponding measurement position;

[0066] Among them, the test points are selected using one of the following methods:

[0067] The test points are a series of continuous track points on the visible satellite motion track, wherein the time interval between any two adjacent points is no more than 1 second, and the total duration is no less than 3 minutes;

[0068] The test points are a series of discrete trajectory points on the visible satellite motion trajectory, wherein the angular interval between any two adjacent points is not less than 5°, and the total number of test points is not less than 15;

[0069] The test point is a combination of a series of trajectory points at the zenith angle and the edge of the communication angle, and the test point repeatedly switches between the series of trajectory points at the zenith angle and the edge of the communication angle;

[0070] For example, the combination order is: (90, 0), (θ Lower ,φ1),(90,0),(θ Lower ,φ2),(90,0),(θ Lower ,φ3),...,(90,0),(θ Lower ,φ N ), where θ Lower is the lower limit of the common faith angle, φ1,…,φ N Indicates the azimuth.

[0071] In one embodiment, for S103 , when the measuring antenna moves to the first test point, the satellite position data corresponding to the first test point is transmitted back to the ground terminal to be measured.

[0072] Specifically, when the measuring antenna moves to the first test point, it sends an in-position handshake signal to the test system; after receiving the in-position handshake signal, the test system transmits the satellite position data corresponding to the first test point to the ground terminal to be tested.

[0073] In one embodiment, for S104, the ground terminal to be tested generates a beam according to the received satellite position data, establishes a connection, and the test system completes the air interface wireless performance measurement of the first test point. Figure 4 The specific process includes:

[0074] S401, sending pre-set target satellite position data to the device under test in real time through the test system;

[0075] S402: The ground terminal to be measured continuously updates the weighting coefficient in real time according to the received target satellite position data to achieve dynamic tracking of the target satellite.

[0076] Under normal circumstances, the phased array device of the ground terminal to be tested obtains its own geographic coordinates through the built-in GNSS / INS combined positioning module, and receives the real-time ephemeris data of the target satellite, and outputs the relative position of the ground terminal to be tested and the target satellite in real time through the spatial geometry solution engine; wherein, the real-time ephemeris data contains orbital parameters and timestamps. The relative position of the ground terminal to be tested and the target satellite is the pitch angle, azimuth angle, and slant range, that is, the satellite position data mentioned above. According to the relative position, the beam control unit dynamically calculates the phase / amplitude weighting coefficient of the antenna array, generates a directional beam pointing to the target satellite through array factor synthesis, and continuously updates the weighting coefficient according to the angular velocity of the target satellite to achieve dynamic beam tracking of the target satellite. Among them, the angular velocity of the target satellite corresponds to the satellite position data update rate.

[0077] In actual application scenarios, the present invention sends pre-set target satellite position data to the device under test in real time through the test system. The device under test continuously updates the weighting coefficient in real time according to the received target satellite position data to achieve dynamic tracking of the target satellite.

[0078] Through the above processing, all test points are traversed to complete the air interface wireless performance measurement of the ground terminal to be tested, and the air interface wireless performance measurement results corresponding to all test points are obtained.

[0079] The testing process of this invention is equivalent in principle to the actual operating process of ground-based satellite terminal phased array equipment, as well as to traditional testing schemes that use multi-probe spherical array test systems to simulate satellite motion scenarios. Furthermore, by eliminating the need for the test system to play the target satellite's real-time ephemeris data and the device under test to calculate the target satellite's position data based on the received real-time ephemeris data, the hardware requirements for the test system are greatly reduced, the testing process is simplified, and the test system's applicability is expanded.

[0080] The air interface wireless performance measurement includes at least: beam agility test, dynamic scanning beam pointing error test, beam pattern test, and dynamic scanning beam tracking test.

[0081] 1. For beam agility testing, the simulated position of the target satellite is switched to trigger the beam redirection of the terminal under test. The signal acquisition system is used to measure the time interval from the issuance of the control command to the new beam being stably pointed at the target.

[0082] 2. For the dynamic scanning beam pointing error test, in a scenario of continuously simulating the satellite motion trajectory, the actual beam pointing angle is inferred through spatial field intensity sampling and inverse beam reconstruction algorithm, and the pointing error is calculated by comparing it with the theoretical pointing angle.

[0083] 3. For dynamic scanning beam tracking tests, in a scenario where the satellite motion trajectory is continuously simulated, the test system continuously collects the transmit signal power and / or receive signal power data of the ground terminal under test to construct a test power data set.

[0084] The test power data set is fitted with the slant range data at the corresponding test points to generate a slant range-power characteristic curve.

[0085] The measured power data set is further subjected to point-by-point difference calculation with the theoretically predicted value at the corresponding slant range point on the characteristic curve (ie, the fitted power data set), and the absolute value is taken to form a difference power data set.

[0086] Finally, the data points exceeding a preset threshold (eg, 5 dB) in the difference power data set are counted, and the corresponding test point positions and the transmit / receive signal power parameters measured at the test point positions are recorded.

[0087] 4. For the beam pattern test, the simulated position of the target satellite is switched to trigger the beam redirection of the terminal under test. After the relevant beam redirection is completed, the test system issues a beam lock command. The ground terminal phased array device under test receives the beam lock command and stops updating the weighting coefficients. The measurement antenna is moved to perform three-dimensional spherical space sampling on the device under test to complete the 3D pattern characteristic measurement of the locked beam. After the measurement is completed, the test system issues a beam unlock command to release the beam lock on the device under test. The measurement antenna moves to the next test point and repeats the above test steps.

[0088] It should be noted that although the operations of the method of the present invention are described in a specific order in the above embodiments and drawings, this does not require or imply that these operations must be performed in this specific order, or that all illustrated operations must be performed to achieve the desired results. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one step, and / or one step may be broken down into multiple steps.

[0089] After introducing the method of the exemplary embodiment of the present invention, next, reference is made to Figure 5An air interface performance testing device for a low-orbit satellite ground terminal according to an exemplary embodiment of the present invention is introduced.

[0090] The implementation of the low-orbit satellite ground terminal air interface performance test device can refer to the implementation of the above method, and the repeated parts will not be repeated. The terms "module" or "unit" used below can be a combination of software and / or hardware that implements the predetermined function. Although the device described in the following embodiments is preferably implemented in software, implementation in hardware, or a combination of software and hardware, is also possible and conceivable.

[0091] Based on the same inventive concept, the present invention also proposes a low-orbit satellite ground terminal air interface performance test device, such as Figure 5 As shown, the device includes:

[0092] The calculation module 510 is used to calculate the satellite position data observed by the ground terminal to be measured at different times based on the preset ground terminal position and low-orbit communication satellite ephemeris data, and generate the visible satellite motion trajectory at the ground terminal position;

[0093] An import module 520 is configured to select a preset number of trajectory points on the visible satellite motion trajectory as test points, and import the satellite position data of the test points into a test system 540;

[0094] The feedback module 530 is configured to transmit the satellite position data corresponding to the first test point to the ground terminal 550 to be tested when the measurement antenna moves to the first test point;

[0095] The ground terminal to be tested 550 generates a beam according to the received satellite position data and establishes a connection, and the test system 540 completes the air interface wireless performance measurement of the first test point;

[0096] Through the above processing, all test points are traversed to complete the air interface wireless performance measurement of the ground terminal to be tested, and the air interface wireless performance measurement results corresponding to all test points are obtained.

[0097] In one embodiment, the calculation module 510 calculates satellite position data observed by the ground terminal at different times based on a preset ground terminal position and low-orbit communication satellite ephemeris data, and generates visible satellite motion trajectories at the ground terminal position, including:

[0098] During a preset simulation cycle, the target satellite is calculated to have a visible start time, an end time, and a duration of each visible period relative to a preset ground terminal to be measured according to a preset communication elevation angle range.

[0099] According to the visible start time, end time and duration of each visibility, the pitch angle, azimuth angle and slant range of the target satellite relative to the ground terminal to be measured at different measurement times in each visible time period are calculated.

[0100] In one embodiment, the calculation module 510 is further configured to:

[0101] The visible satellite motion trajectory is determined based on the slant range, azimuth, and pitch angle of the target satellite relative to a preset ground terminal to be measured at different measurement times within the visible time period. The visible satellite motion trajectory reflects the change in the target satellite position over time within the visible time period. The slant range is the real-time distance between the target satellite and the ground terminal to be measured, and is obtained by normalization based on the maximum value of the slant range on the visible target satellite motion trajectory.

[0102] In one embodiment, the satellite position data further includes a real-time gain correction factor for the target satellite antenna beam;

[0103] For different measurement moments within each visible time period, calculate the pitch angle and azimuth angle of the preset ground terminal to be measured relative to the target satellite, and calculate the corresponding real-time gain correction coefficient according to one of the following methods:

[0104] K(θ)=cos n (θ);

[0105] Where K(θ) represents the real-time gain correction coefficient; θ is the preset pitch angle of the ground terminal to be measured relative to the target satellite; n is the pattern factor, which depends on the shape of the antenna pattern. Among them, θ HPBW is the half-power beamwidth of the target satellite antenna in the elevation direction;

[0106] K(θ)=sinc n (θ);

[0107] Where K(θ) represents the real-time gain correction coefficient; θ is the preset pitch angle of the ground terminal to be measured relative to the target satellite; n is the pattern factor, which depends on the shape of the antenna pattern. Among them, θ HPBW is the half-power beamwidth of the target satellite antenna in the elevation direction;

[0108] K(θ, φ)=cos n1 (θ)·sin n2 (φ);

[0109] Wherein, K(θ, φ) represents the real-time gain correction coefficient; θ is the preset pitch angle of the ground terminal to be measured relative to the target satellite; φ is the preset azimuth angle of the ground terminal to be measured relative to the target satellite; θ HPBW ,φ HPBW are the half-power beamwidths in the elevation and azimuth directions of the target satellite antenna, respectively.

[0110] In one embodiment, the import module 520 selects a preset number of trajectory points on the visible satellite motion trajectory as test points and imports the satellite position data of the test points into the test system, including:

[0111] A series of measurement positions are generated according to the imported satellite position data; during the test process, the test system controls the measurement antenna to move to each measurement position one by one, and completes the air interface wireless performance measurement of the ground terminal under test at the corresponding measurement position;

[0112] Among them, the test points are selected using one of the following methods:

[0113] The test points are a series of continuous track points on the visible satellite motion track, wherein the time interval between any two adjacent points is no more than 1 second, and the total duration is no less than 3 minutes;

[0114] The test points are a series of discrete trajectory points on the visible satellite motion trajectory, wherein the angular interval between any two adjacent points is not less than 5°, and the total number of test points is not less than 15;

[0115] The test point is a combination of a series of trajectory points of the zenith angle and the edge of the communication angle, and the test point repeatedly switches between the zenith angle and the series of trajectory points of the edge of the communication angle.

[0116] In one embodiment, when the measuring antenna moves to the first test point, the feedback module 530 transmits the satellite position data corresponding to the first test point to the ground terminal to be tested, including:

[0117] When the measuring antenna moves to the first test point, it sends an in-position handshake signal to the test system 540; wherein, after receiving the in-position handshake signal, the test system 540 transmits the satellite position data corresponding to the first test point to the ground terminal to be tested.

[0118] In one embodiment, the ground terminal to be tested 550 generates a beam based on the received satellite position data and establishes a connection, and the test system 540 completes the air interface wireless performance measurement of the first test point, including:

[0119] Sending pre-set target satellite position data to the device under test in real time through the test system 540;

[0120] The ground terminal to be tested continuously updates the weighting coefficient in real time according to the received target satellite position data to achieve dynamic tracking of the target satellite.

[0121] In one embodiment, the air interface wireless performance measurement includes at least: beam agility test, dynamic scanning beam pointing error test, beam pattern test, and dynamic scanning beam tracking test.

[0122] In one embodiment, for beam agility testing, the simulated position of the target satellite is switched to trigger beam redirection of the terminal under test, and the time interval from the issuance of the control command to the new beam being stably pointed at the target is measured using a signal acquisition system;

[0123] For the dynamic scanning beam pointing error test, in a scenario of continuously simulating the satellite motion trajectory, the actual beam pointing angle is inferred through spatial field intensity sampling and inverse beam reconstruction algorithm, and the pointing error is calculated by comparing it with the theoretical pointing angle.

[0124] For dynamic scanning beam tracking testing, in a scenario of continuously simulating the satellite motion trajectory, the test system continuously collects the transmit signal power and / or receive signal power data of the ground terminal under test to construct a test power data set; a function is fitted between the test power data set and the slant range data at the corresponding test point to generate a slant range-power characteristic curve; the measured power data set is further differentially calculated point by point with the theoretical predicted value at the corresponding slant range point on the characteristic curve and the absolute value is taken to form a difference power data set; the data points in the difference power data set that exceed the preset threshold are counted, and the corresponding test point position and the transmit / receive signal power parameters measured at the test point position are recorded;

[0125] For beam pattern testing, the simulated position of the target satellite is switched to trigger beam redirection of the terminal under test. After completing the relevant beam redirection, the test system issues a beam lock command. The ground terminal phased array device under test receives the beam lock command and stops updating the weighting coefficients. The measurement antenna is moved to perform three-dimensional spherical spatial sampling on the device under test to complete the 3D pattern characteristic measurement of the locked beam. After the measurement is completed, the test system issues a beam unlock command to release the beam lock on the device under test. The measurement antenna moves to the next test point and repeats the above test steps.

[0126] It should be noted that although several modules of the low-orbit satellite ground terminal air interface performance test device are mentioned in the detailed description above, this division is merely exemplary and not mandatory. In fact, according to embodiments of the present invention, the features and functions of two or more modules described above can be embodied in a single module. Conversely, the features and functions of a single module described above can be further divided and embodied by multiple modules.

[0127] Based on the above invention concept, Figure 6As shown, the present invention also proposes a computer device 600, including a memory 610, a processor 620, and a computer program 630 stored in the memory 610 and executable on the processor 620. When the processor 620 executes the computer program 630, the aforementioned low-orbit satellite ground terminal air interface performance test method is implemented.

[0128] Based on the aforementioned inventive concept, the present invention proposes a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, it implements the aforementioned low-orbit satellite ground terminal air interface performance test method.

[0129] Based on the aforementioned inventive concept, the present invention proposes a computer program product, which includes a computer program. When the computer program is executed by a processor, it implements a method for testing the air interface performance of a low-orbit satellite ground terminal.

[0130] The low-orbit satellite ground terminal air interface performance test method and device proposed in the present invention maps the actual motion trajectory of the target low-orbit communication satellite into a series of continuous / discrete measurement antenna positions, simulating satellite motion scenarios by measuring continuous / discrete changes in antenna positions. The test system then sends pre-set target satellite position data to the device under test in real time, replacing the traditional process in which the device under test calculates the relative position of the ground terminal under test and the target satellite in real time based on the received target satellite ephemeris and its own precise position. Compared to the actual operating process of ground satellite terminal phased array equipment in low-orbit satellite communication scenarios, and compared to traditional test solutions that use multi-probe spherical array test systems to simulate satellite motion scenarios, the present invention can complete dynamic multi-beam performance measurements of low-orbit satellite ground terminal phased array equipment in a single-probe darkroom, achieving test accuracy and principle equivalence essentially equivalent to traditional test solutions. This significantly reduces the complexity of the test system, as well as the construction, maintenance, and testing costs of the test system, providing strong technical support for air interface performance testing.

[0131] The acquisition, storage, use, and processing of data in the technical solution of this application comply with relevant laws and regulations.

[0132] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, apparatus, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0133] The present invention is described with reference to flowcharts and / or block diagrams of methods and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0134] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0135] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0136] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present invention, which are used to illustrate the technical solutions of the present invention, rather than to limit them. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the above-described embodiments, those skilled in the art should understand that any person skilled in the art can modify or easily conceive of changes to the technical solutions described in the above-described embodiments within the technical scope disclosed by the present invention, or replace some of the technical features therein with equivalents. Such modifications, changes, or replacements do not deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. A method for testing the air interface performance of a low-orbit satellite ground terminal, characterized in that: include: Based on the preset ground terminal position and low-orbit communication satellite ephemeris data, the satellite position data observed by the ground terminal to be tested at different times are calculated, and the visible satellite motion trajectory of the ground terminal position is generated; Selecting a preset number of trajectory points on the visible satellite motion trajectory as test points, and importing satellite position data of the test points into a test system; When the measuring antenna moves to the first test point, the satellite position data corresponding to the first test point is transmitted back to the ground terminal to be tested; The ground terminal to be tested generates a beam according to the received satellite position data and establishes a connection, and the test system completes the air interface wireless performance measurement of the first test point; Through the above processing, all test points are traversed to complete the air interface wireless performance measurement of the ground terminal to be tested, and the air interface wireless performance measurement results corresponding to all test points are obtained.

2. The low-orbit satellite ground terminal air interface performance test method according to claim 1, characterized in that: Based on the preset ground terminal position and low-orbit communication satellite ephemeris data, the satellite position data observed by the ground terminal at different times is calculated, and the visible satellite motion trajectory of the ground terminal position is generated, including: During a preset simulation cycle, the target satellite is calculated to have a visible start time, an end time, and a duration of each visible period relative to a preset ground terminal to be measured according to a preset communication elevation angle range. According to the visible start time, end time and duration of each visibility, the pitch angle, azimuth angle and slant range of the target satellite relative to the ground terminal to be measured at different measurement times in each visible time period are calculated.

3. The low-orbit satellite ground terminal air interface performance test method according to claim 1, characterized in that: The method further includes: The visible satellite motion trajectory is determined based on the slant range, azimuth, and pitch angle of the target satellite relative to a preset ground terminal to be measured at different measurement times within the visible time period. The visible satellite motion trajectory reflects the change in the target satellite position over time within the visible time period. The slant range is the real-time distance between the target satellite and the ground terminal to be measured, and is obtained by normalization based on the maximum value of the slant range on the visible target satellite motion trajectory.

4. The low-orbit satellite ground terminal air interface performance testing method according to claim 1, characterized in that: The satellite position data also includes a real-time gain correction factor for the target satellite antenna beam; For different measurement moments within each visible time period, calculate the pitch angle and azimuth angle of the preset ground terminal to be measured relative to the target satellite, and calculate the corresponding real-time gain correction coefficient according to one of the following methods: K(θ)=cos n (i); Where K(θ) represents the real-time gain correction coefficient; θ is the preset pitch angle of the ground terminal to be measured relative to the target satellite; n is the pattern factor, which depends on the shape of the antenna pattern. Among them, θ HPBW is the half-power beamwidth of the target satellite antenna in the elevation direction; K(θ)=sinc n (θ); Where K(θ) represents the real-time gain correction coefficient; θ is the preset pitch angle of the ground terminal to be measured relative to the target satellite; n is the pattern factor, which depends on the shape of the antenna pattern. Among them, θ HPBW is the half-power beamwidth of the target satellite antenna in the elevation direction; K(θ,φ)=cos n1 (θ)·sin n2 (f); Wherein, K(θ, φ) represents the real-time gain correction coefficient; θ is the preset pitch angle of the ground terminal to be measured relative to the target satellite; φ is the preset azimuth angle of the ground terminal to be measured relative to the target satellite; θ HPBW ,φ HPBW are the half-power beamwidths in the elevation and azimuth directions of the target satellite antenna, respectively.

5. The low-orbit satellite ground terminal air interface performance test method according to claim 1, characterized in that: Selecting a preset number of trajectory points on the visible satellite motion trajectory as test points, and importing satellite position data of the test points into a test system, including: A series of measurement positions are generated according to the imported satellite position data; during the test process, the test system controls the measurement antenna to move to each measurement position one by one, and completes the air interface wireless performance measurement of the ground terminal under test at the corresponding measurement position; Among them, the test points are selected using one of the following methods: The test points are a series of continuous track points on the visible satellite motion track, wherein the time interval between any two adjacent points is no more than 1 second, and the total duration is no less than 3 minutes; The test points are a series of discrete trajectory points on the visible satellite motion trajectory, wherein the angular interval between any two adjacent points is not less than 5°, and the total number of test points is not less than 15; The test point is a combination of a series of trajectory points of the zenith angle and the edge of the communication angle, and the test point repeatedly switches between the zenith angle and the series of trajectory points of the edge of the communication angle.

6. The low-orbit satellite ground terminal air interface performance test method according to claim 1, characterized in that: When the measuring antenna moves to the first test point, the satellite position data corresponding to the first test point is transmitted back to the ground terminal to be tested, including: When the measuring antenna moves to the first test point, it sends an in-position handshake signal to the test system; wherein, after receiving the in-position handshake signal, the test system transmits the satellite position data corresponding to the first test point to the ground terminal to be tested.

7. The low-orbit satellite ground terminal air interface performance testing method according to claim 1, characterized in that: The ground terminal to be tested generates a beam according to the received satellite position data and establishes a connection, and the test system completes the air interface wireless performance measurement of the first test point, including: Send the preset target satellite position data to the device under test in real time through the test system; The ground terminal to be tested continuously updates the weighting coefficient in real time according to the received target satellite position data to achieve dynamic tracking of the target satellite.

8. The low-orbit satellite ground terminal air interface performance test method according to claim 1, characterized in that: The air interface wireless performance measurement includes at least: beam agility test, dynamic scanning beam pointing error test, beam pattern test, and dynamic scanning beam tracking test.

9. The low-orbit satellite ground terminal air interface performance test method according to claim 8, characterized in that: For beam agility testing, the simulated position of the target satellite is switched to trigger the beam redirection of the terminal under test. The signal acquisition system is used to measure the time interval from the issuance of the control command to the stable pointing of the new beam to the target. For the dynamic scanning beam pointing error test, in a scenario of continuously simulating the satellite motion trajectory, the actual beam pointing angle is inferred through spatial field intensity sampling and inverse beam reconstruction algorithm, and the pointing error is calculated by comparing it with the theoretical pointing angle. For dynamic scanning beam tracking testing, in a scenario of continuously simulating the satellite motion trajectory, the test system continuously collects the transmit signal power and / or receive signal power data of the ground terminal under test to construct a test power data set; a function is fitted between the test power data set and the slant range data at the corresponding test point to generate a slant range-power characteristic curve; the measured power data set is further differentially calculated point by point with the theoretical predicted value at the corresponding slant range point on the characteristic curve and the absolute value is taken to form a difference power data set; the data points in the difference power data set that exceed the preset threshold are counted, and the corresponding test point position and the transmit / receive signal power parameters measured at the test point position are recorded; For beam pattern testing, the simulated position of the target satellite is switched to trigger the beam redirection of the terminal under test; After completing the relevant beam redirection, the test system issues a beam lock command. The ground terminal phased array device under test receives the beam lock command and stops updating the weighting coefficients. The measurement antenna is moved to perform three-dimensional spherical space sampling on the device under test to complete the 3D radiation pattern characteristic measurement of the locked beam. After the measurement is completed, the test system issues a beam unlock command to release the beam lock on the device under test. The measurement antenna moves to the next test point and repeats the above test steps.

10. A low-orbit satellite ground terminal air interface performance test device, characterized in that: include: A calculation module is used to calculate the satellite position data observed by the ground terminal to be tested at different times based on the preset ground terminal position and low-orbit communication satellite ephemeris data, and generate the visible satellite motion trajectory of the ground terminal position; An import module is used to select a preset number of trajectory points on the visible satellite motion trajectory as test points, and import the satellite position data of the test points into the test system; A return module is used to return the satellite position data corresponding to the first test point to the ground terminal to be tested when the measurement antenna moves to the first test point; The ground terminal to be tested generates a beam according to the received satellite position data and establishes a connection, and the test system completes the air interface wireless performance measurement of the first test point; Through the above processing, all test points are traversed to complete the air interface wireless performance measurement of the ground terminal to be tested, and the air interface wireless performance measurement results corresponding to all test points are obtained.

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