Low-orbit satellite group inter-satellite laser communication networking test system and method

Abstract

The invention discloses a networking test system and method for laser communication between low-orbit star groups, and belongs to the technical field of satellite communication, the networking test system comprises a satellite attitude simulation device, a light beam far-field characteristic simulation device and a ground side simulation device, and the satellite attitude simulation device is used for simulating the orbit, attitude and vibration change of a satellite platform in a satellite laser link; the light beam far-field characteristic simulation equipment is used for simulating the distribution state and attenuation dynamic change of the laser beams in the inter-satellite laser link of the low-orbit satellite group after long-distance transmission according to the laser signal; and the ground side simulation equipment is used for receiving the orbit, attitude and vibration change data of the satellite platform and the distribution state and attenuation dynamic change data of the laser beams after long-distance transmission, and cooperates with the laser communication terminal to complete the performance test of the inter-satellite laser communication networking of the low-orbit satellite group. According to the invention, a one-to-many low-orbit satellite group inter-satellite laser communication link performance test and a low-orbit satellite group inter-satellite multi-node laser communication networking performance test can be supported.

Description

Technical Field

[0001] The present invention relates to the field of satellite communication technology, and in particular to a low-orbit satellite cluster inter-satellite laser communication networking test system and method. Background Art

[0002] Compared with microwave communication, laser communication has outstanding advantages such as large transmission capacity, good confidentiality and strong anti-interference ability. It is not only an important development trend of link data transmission technology between satellites and between satellites and ground stations, but also one of the best ways to solve high-speed space communication and precision ranging problems.

[0003] With the continuous development of aerospace technology, building a high-speed and stable intersatellite laser communication link information network is an inevitable trend for satellite systems to develop towards networking. The key characteristics of intersatellite laser communication links, such as frequency selection, signal system, link establishment method, communication capacity, capture time, and tracking accuracy, determine the comprehensive performance of the intersatellite information transmission network. Since low-orbit satellites are in a high-speed mobile state, higher requirements are placed on laser communication scanning alignment and stable link establishment. How to build a ground equivalent simulation test system for laser communication for low-orbit satellites is of great significance to supporting the on-orbit testing and application of intersatellite laser communication.

[0004] At present, laser communication terminals and corresponding ground test systems are mainly based on "one-to-one" communication, which is used to establish and test point-to-point high-speed communication links. However, this communication method requires a large number of laser communication terminals and poor compatibility of network nodes. With the development of laser communication networking and scale, "one-to-one" communication can no longer meet communication needs, and it is impossible to achieve multi-standard compatible laser communication from a single target to multiple targets and multi-node laser communication networking performance testing requirements between low-orbit satellite clusters. Summary of the invention

[0005] In order to solve some or all of the technical problems existing in the above-mentioned prior art, the present invention provides a low-orbit star cluster inter-satellite laser communication networking test system and method, which supports the detection of dynamic capture, tracking, communication and networking capabilities of satellite laser communication terminals under the interference of dynamic environment changes, and supports "one-to-many" low-orbit star cluster inter-satellite laser communication link performance test and low-orbit star cluster inter-satellite multi-node laser communication networking performance test.

[0006] The technical solution of the present invention is as follows: In a first aspect, the present invention provides a low-orbit satellite cluster inter-satellite laser communication networking test system, comprising: A satellite attitude simulation device, wherein the satellite attitude simulation device is used to simulate the orbit, attitude and vibration changes of the satellite platform in the satellite laser link; A light beam far-field characteristic simulation device, which is used to simulate the distribution state and attenuation dynamic changes of the laser beam in the inter-satellite laser link of the low-orbit star cluster after long-distance transmission according to the laser signal; The ground-side simulation device is used to receive the satellite platform orbit, attitude and vibration change data simulated by the satellite attitude simulation device and the distribution state and attenuation dynamic change data of the laser beam after long-distance transmission simulated by the beam far-field characteristic simulation device, and cooperate with the laser communication terminal to complete the low-orbit star cluster inter-satellite laser communication networking performance test.

[0007] Furthermore, in the above-mentioned low-orbit satellite cluster inter-satellite laser communication networking test system, the satellite attitude simulation device includes: A two-dimensional turntable, which is used to simulate the orbit and attitude changes of the satellite platform in the low-orbit constellation laser link; A oscillating platform is used to simulate the vibration changes of a satellite platform in a low-orbit constellation laser link.

[0008] Furthermore, in the above-mentioned low-orbit satellite cluster inter-satellite laser communication networking test system, the light beam far-field characteristic simulation device includes: A collimator, which is used to obtain a parallel light beam to simulate the long-distance transmission of a laser beam; An optical attenuator, the optical attenuator is used to simulate the energy loss of interstellar laser beams during long-distance transmission; An optical platform, wherein the optical platform is used to support the collimator, the optical attenuator and other equipment and components used to support the low-orbit star cluster inter-satellite laser communication networking test.

[0009] Furthermore, in the above-mentioned low-orbit satellite cluster inter-satellite laser communication networking test system, the ground-side simulation device includes: An optical antenna, wherein the optical antenna is used to receive a laser signal emitted by the laser communication terminal; An optical signal processing module, the optical signal processing module is used to convert the laser signal received by the optical antenna into an electrical signal, and to demodulate and decode the electrical signal; A beam quality analyzer, wherein the beam quality analyzer is used to detect the quality of the parallel light beam generated by the collimator; An optical power meter, the optical power meter is used to measure the laser power received by the optical antenna; A control module, wherein the control module is used to receive and process data from the satellite attitude simulation device, the light beam far-field characteristic simulation device and the ground-side simulation device. At the same time, the control module combines the orbit information, attitude information and vibration information of the satellite in the laser link simulated by the satellite attitude simulation device, the distribution state and attenuation dynamic changes of the laser beam in the low-orbit star cluster inter-satellite laser link simulated by the light beam far-field characteristic simulation device after long-distance transmission, and the information sent and received by the communication link to perform a performance test of the low-orbit star cluster inter-satellite laser communication network.

[0010] In a second aspect, the present invention further provides a method for testing a low-orbit satellite cluster inter-satellite laser communication network, comprising: Receive laser signals containing inter-satellite information of low-orbiting star clusters; Convert the received laser signal into an electrical signal to obtain the original information between the stars in the low-orbit star cluster; The performance of the low-orbit star cluster inter-satellite laser communication network is tested based on the original information obtained and the orbit information, attitude information, vibration information of the satellites in the simulated low-orbit star cluster laser link, as well as the distribution state and attenuation dynamic change information of the laser beam after long-distance transmission.

[0011] Furthermore, in the above-mentioned low-orbit star cluster inter-satellite laser communication networking test method, the performance of the low-orbit star cluster inter-satellite laser communication networking tested includes: capture performance, tracking performance, communication rate, packet loss rate and delay performance.

[0012] Further, in the above-mentioned low-orbit star cluster inter-satellite laser communication networking test method, testing the capture performance of the low-orbit star cluster inter-satellite laser communication networking includes: Initialize the laser communication terminal and the ground-side simulation equipment; When the ground-side simulation device receives the signal light emitted by the laser communication terminal, the ground-side simulation device is adjusted in a direction so that the signal light of the ground-side simulation device is aimed at the laser communication terminal; When the laser communication terminal receives the signal light of the analog device on the ground side, it adjusts its own direction so that the signal light of the laser communication terminal is aimed at the analog device on the ground side; When the laser communication terminal and the ground-side simulation equipment stably track the signal light of the other party within their own precision tracking field of view or the precision tracking detector continuously detects the optical signal, they switch to the precision tracking mode. At this time, the terminal is judged to have successfully captured, and the number of captures is increased by 1. At this time, the timing value T1 is read, and T1-T0 is used as the capture time, and T0 represents the start time of self-scanning; multiple captures are performed, and the number of captures and capture times are recorded at the same time. The number of captures is divided by the total number of tests as the corresponding capture success rate, and the average capture time is taken as the corresponding capture success time.

[0013] Further, in the above-mentioned low-orbit star cluster inter-satellite laser communication networking test method, testing the tracking performance of the low-orbit star cluster inter-satellite laser communication networking includes: Initialize the laser communication terminal and the ground-side simulation equipment; When the ground-side simulation device receives the signal light of the laser communication terminal, the ground-side simulation device adjusts its own direction so that the signal light of the ground-side simulation device is aimed at the laser communication terminal; When the laser communication terminal receives the signal light from the ground-side simulation device, the laser communication terminal stops scanning and automatically adjusts its own direction so that the signal light of the laser communication terminal is aimed at the ground-side simulation device; the laser communication terminal and the ground-side simulation device stably track the signal light of the other party within their own precision tracking field of view or the precision tracking detector continuously detects the optical signal, and switches to the precision tracking mode; The laser communication terminal and the ground-side simulation equipment maintain stable tracking for 60 seconds; The laser communication terminal is controlled to rotate at a preset speed, the tracking residual of the capture tracking camera is recorded, the recording is stopped after the preset movement time, the off-target amount data during the tracking process is recorded and the standard deviation is calculated as the corresponding tracking accuracy.

[0014] Further, in the above-mentioned low-orbit star cluster inter-satellite laser communication networking test method, testing the communication rate and packet loss rate of the low-orbit star cluster inter-satellite laser communication networking includes: Initialize the laser communication terminal and the ground-side simulation equipment; Keep the laser communication terminal and the ground-side simulation equipment stably tracked for 60 seconds; Set the signal light transmission power and link attenuation value of the laser communication terminal; The laser communication terminal is restored to a working state, the laser communication terminal sends an optical signal and sets the communication rate to a preset value; Adjust the optical attenuator to minimize the intensity of the optical signal received by the analog device on the ground side; The analog device on the ground side demodulates the received optical signal, compares it with the transmitted data, and counts the number of received error packets; Set different communication rates and calculate the packet loss rates corresponding to different communication rates.

[0015] Further, in the above-mentioned low-orbit star cluster inter-satellite laser communication networking test method, testing the delay performance of the low-orbit star cluster inter-satellite laser communication networking includes: Initialize the laser communication terminal and the ground-side simulation equipment; The laser communication terminal and the ground-side simulation equipment maintain stable tracking for 60 seconds; Use network cables to connect multiple ground-side simulation devices, use the laser communication terminal and the ground-side simulation devices as nodes, set one of the ground-side simulation devices as the master node, and set the IP addresses and initial states of multiple nodes; Set the node configuration table, planning routing table and routing management mode of the current network according to the networking strategy; The service data packets that need to be forwarded through the inter-satellite laser link are registered through the master node; Verify whether the destination node has correctly received the service data packet, record the time when the service data packet is sent and received, and obtain the service data packet forwarding delay performance.

[0016] The main advantages of the technical solution of the present invention are as follows: The low-orbit star cluster intersatellite laser communication networking test system and method of the present invention use the laser communication terminal as the sending part of the laser communication networking test system to perform multi-channel laser signal transmission in time sharing, use the ground-side simulation equipment as the receiving part of the laser communication networking test system to receive the multi-channel laser signals sent from the above laser communication terminal in time sharing, and convert the multi-channel laser signals into electrical signals for demodulation and decoding to obtain the original transmitted information, so as to test the performance of the low-orbit star cluster intersatellite laser communication networking. The low-orbit star cluster intersatellite laser communication networking test system of the present invention can send and receive laser signals from multiple low-orbit satellites, and realize the performance test of the intersatellite laser communication networking of multiple low-orbit satellites. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings described herein are used to provide a further understanding of the embodiments of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings: Figure 1 A schematic diagram of the structure of a low-orbit satellite cluster inter-satellite laser communication networking test system provided by an embodiment of the present invention; Figure 2 A schematic diagram of a flow chart of a method for testing a low-orbit satellite cluster inter-satellite laser communication network according to an embodiment of the present invention; Figure 3 A schematic diagram of a flow chart of testing capture performance in a method for testing a low-orbit satellite cluster inter-satellite laser communication network provided by an embodiment of the present invention; Figure 4 A schematic diagram of a flow chart of testing tracking performance in a method for testing a low-orbit satellite cluster inter-satellite laser communication network provided by an embodiment of the present invention; Figure 5 A schematic diagram of a flow chart of testing the communication rate and packet loss rate in a method for testing a low-orbit satellite cluster inter-satellite laser communication networking provided by an embodiment of the present invention; Figure 6A schematic diagram of a process for testing delay performance in a low-orbit satellite cluster inter-satellite laser communication networking test method provided by an embodiment of the present invention.

[0018] Description of reference numerals: 1. Satellite attitude simulation equipment; 2. Light beam far-field characteristics simulation equipment; 3. Ground-side simulation equipment; 11. Two-dimensional turntable; 12. Swinging platform; 21. Collimator; 22. Optical attenuator; 23. Optical platform; 31. Optical antenna; 32. Optical signal processing module; 33. Beam quality analyzer; 34. Optical power meter; 35. Control module. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0020] The technical solution provided by the embodiments of the present invention is described in detail below with reference to the accompanying drawings.

[0021] As attached Figure 1 As shown, an embodiment of the present invention provides a low-orbit satellite cluster inter-satellite laser communication networking test system, the test system comprising: a satellite attitude simulation device 1, a beam far-field characteristic simulation device 2 and a ground-side simulation device 3, wherein: The satellite attitude simulation device 1 is used to simulate the orbit, attitude and vibration changes of the satellite platform in the satellite laser link; the light beam far-field characteristic simulation device 2 is used to simulate the distribution state and attenuation dynamic changes of the laser beam in the low-orbit star cluster inter-satellite laser link after long-distance transmission according to the laser signal; the ground-side simulation device 3 is used to receive the satellite platform orbit, attitude and vibration change data simulated by the satellite attitude simulation device 1 and the distribution state and attenuation dynamic change data of the laser beam after long-distance transmission simulated by the light beam far-field characteristic simulation device 2, and cooperate with the laser communication terminal to complete the low-orbit star cluster inter-satellite laser communication networking performance test.

[0022] Specifically, a laser communication terminal can be mounted on the satellite attitude simulation device 1 so that the laser communication terminal can receive and store laser signals in real time. The satellite attitude simulation device 1 receives the original motion data between the low-orbit star cluster set by the ground-side simulation device 3 and simulates the orbit information, attitude information and vibration information of the satellite in the laser link. The light beam far-field characteristic simulation device 2 receives the device parameters set by the ground-side simulation device 3 to simulate the distribution state and attenuation dynamic changes of the laser beam in the low-orbit star cluster inter-satellite laser link after long-distance transmission. The ground-side simulation device 3 is connected to the satellite attitude simulation device 1 and the light beam far-field characteristic simulation device 2 through a cable or optical fiber. The ground-side simulation device 3 is used to convert the received laser signal into an electrical signal, and convert the information transmitted by the laser signal into the original information after amplification and demodulation, and combine the information sent by the above-mentioned laser communication terminal to perform performance testing of the low-orbit star cluster inter-satellite laser communication network.

[0023] Specifically, the principles of the low-orbit satellite cluster inter-satellite laser communication networking test system of the present invention include: By carrying a laser communication terminal on the satellite attitude simulation device 1, the laser communication terminal is used as the sending part of the laser communication networking test system to emit laser signals, and the satellite orbit information, attitude information and vibration information in the laser link are simulated according to the satellite motion data set by the received ground-side simulation device 3, and the deflection angle and other information are transmitted back to the ground-side simulation device 3 for data analysis; the ground-side simulation device 3 is used as the receiving part of the laser communication networking test system to receive the laser signal emitted by the laser communication terminal on the satellite attitude simulation device 1, and the received laser signal is subjected to photoelectric conversion, decoding, demodulation and other processing to obtain the original transmission information, and the distribution state and attenuation dynamic change of the far-field beam in the low-orbit star cluster inter-satellite laser link simulated by the beam far-field characteristic simulation device 2 after long-distance transmission are combined, so as to test the performance of the low-orbit star cluster inter-satellite laser communication networking. At the same time, in the low-orbit star cluster inter-satellite laser communication networking test system of the present invention, the laser communication terminal is used as the sending part of the laser communication networking test system, and multi-channel laser signal transmission is performed in time-sharing, and the ground-side simulation device 3 is used as the receiving part of the laser communication networking test system, and multi-channel laser signals emitted by the above-mentioned laser communication terminal are received in time-sharing. Therefore, the low-orbit star cluster inter-satellite laser communication networking test system of the present invention can send and receive laser signals from multiple low-orbit satellites, thereby realizing inter-satellite laser communication networking performance testing of multiple low-orbit satellites.

[0024] Specifically, the satellite attitude simulation device 1 comprises: a two-dimensional turntable 11 and a swing platform 12, wherein: The two-dimensional turntable 11 is used to simulate the orbit and attitude changes of the satellite platform in the low-orbit star cluster laser link; the swing platform 12 is used to simulate the vibration changes of the satellite platform in the low-orbit star cluster laser link.

[0025] In this way, by using the two-dimensional turntable 11 and the swing platform 12 to individually simulate the orbit, attitude and vibration of the satellite platform in the low-orbit constellation laser link, different vibration spectrum change parameters can be set to simulate the platform angular vibration, thereby completing the vibration compensation capability test of the laser communication terminal.

[0026] Specifically, the above-mentioned light beam far-field characteristic simulation device 2 includes: a collimator 21, an optical attenuator 22 and an optical platform 23, wherein: The collimator 21 is used to obtain a parallel light beam to simulate the long-distance transmission of a laser beam; the optical attenuator 22 is used to attenuate the laser signal sent by the laser communication terminal on the satellite attitude simulation device 1 to simulate the energy loss of the long-distance transmission of the intersatellite laser beam; the optical platform 23 is used to support the collimator 21, the optical attenuator 22 and other equipment and components used to support the intersatellite laser communication networking test of the low-orbit star cluster.

[0027] In the embodiment of the present invention, other equipment and components for the low-orbit star cluster inter-satellite laser communication networking test are set according to actual needs.

[0028] Specifically, the above-mentioned ground-side simulation device 3 includes: an optical antenna 31, an optical signal processing module 32, a beam quality analyzer 33, an optical power meter 34 and a control module 35, wherein: The optical antenna 31 is used to receive the laser signal emitted by the laser communication terminal; the optical signal processing module 32 is used to convert the laser signal received by the optical antenna 31 into an electrical signal, and demodulate and decode the electrical signal; the beam quality analyzer 33 is used to detect the quality of the parallel beam obtained by the parallel light tube 21; the optical power meter 34 is used to measure the size of the laser power received by the optical antenna 31; the control module 35 is used to receive and process the data of the satellite attitude simulation device 1, the beam far-field characteristic simulation device 2 and the ground-side simulation device 3. At the same time, the control module 35 can also combine the orbit information, attitude information and vibration information of the satellite in the laser link simulated by the satellite attitude simulation device 1, and the distribution state and attenuation dynamic changes of the laser beam in the low-orbit star cluster inter-satellite laser link simulated by the beam far-field characteristic simulation device 2 after long-distance transmission, to test the networking performance of the low-orbit star cluster inter-satellite laser communication.

[0029] In some optional implementations of this embodiment, the control module 35 is a host computer.

[0030] It should also be noted that in addition to using the optical antenna 31 to receive the laser signal emitted by the laser communication terminal, the ground-side simulation device 3 in the present invention can also receive the test data transmitted by the satellite attitude simulation device 1 and the light beam far-field characteristic simulation device 2 in real time through cables or optical fibers, which is used for real-time monitoring of indicators such as the working mode, aiming angle, capture status, coarse tracking accuracy, and fine tracking accuracy of the laser communication terminal.

[0031] In summary, the low-orbit star cluster inter-satellite laser communication networking test system of the present invention uses the laser communication terminal as the sending part of the laser communication networking test system, and uses the ground-side simulation device 3 as the receiving part of the laser communication networking test system. By setting multiple optical antennas 31 on a laser communication terminal, laser signals can be emitted by different optical antennas 31 at different times. At the same time, multiple ground-side simulation devices 3 process the laser signals after receiving them at different times, thereby achieving the effect of time-sharing communication. In addition, since the test data fed back by the satellite attitude simulation device 1 and the light beam far-field characteristic simulation device 2 can be received by the ground-side cable or optical fiber interface to the ground-side simulation device 3, the low-orbit star cluster inter-satellite laser communication networking test system of the present invention can support the dynamic capture, tracking, communication and networking capabilities of satellite laser communication terminals under the interference of dynamic environment changes, and can also support "one-to-many" low-orbit star cluster inter-satellite laser communication link performance test and low-orbit star cluster inter-satellite multi-node laser communication networking performance test.

[0032] In a second aspect, the present invention also provides a method for testing a low-orbit satellite cluster inter-satellite laser communication network. Figure 2 As shown, including: Receive laser signals containing inter-satellite information of the low-orbit star cluster; convert the received laser signals into electrical signals to obtain original inter-satellite information of the low-orbit star cluster; test the performance of the low-orbit star cluster inter-satellite laser communication network based on the obtained original information and the orbit information, attitude information, vibration information of the satellites in the simulated low-orbit star cluster laser link, and the distribution state and attenuation dynamic change information of the laser beam after long-distance transmission.

[0033] Therefore, a low-orbit star cluster inter-satellite laser communication networking test method of the present invention tests the performance of the low-orbit star cluster inter-satellite laser communication networking by using the orbit information, attitude information, vibration information of the satellites in the simulated low-orbit star cluster laser link and the distribution state and attenuation dynamic change information of the laser beam after long-distance transmission, and can realize the simultaneous measurement of the performance of multiple inter-satellite laser communication links with different orbits and channels.

[0034] Specifically, the performance of the above-mentioned low-orbit star cluster inter-satellite laser communication networking tested includes at least: capture performance, tracking performance, communication rate, packet loss rate and delay performance.

[0035] The following uses 4 lasers as an example to illustrate the performance test methods of the above-mentioned capture performance, tracking performance, communication rate, packet loss rate and delay performance.

[0036] Specifically, in combination with the above-mentioned low-orbit star cluster inter-satellite laser communication networking test system, the capture performance of the above-mentioned low-orbit star cluster inter-satellite laser communication networking is tested, such as Figure 3 As shown, including: S101: placing the laser communication terminal on the high-precision two-dimensional turntable 11, and adjusting the two-dimensional turntable 11 and the fast reflection mirror respectively so that the optical axes of the four-way laser communication terminal coincide with the optical axes of the corresponding test collimator 21; S102: Adjust the azimuth and elevation directions of the 4-way laser communication terminal, monitor the output of the tracking camera’s miss distance in real time, and make it stay within the capture field of view of the laser communication terminal; S103: The laser communication terminal is set to transmit 1540.56nm and receive 1563.05nm laser; the ground-side simulation device 3 is set to transmit 1563.05nm and receive 1540.56nm laser; S104: setting the initial bias values ​​of the laser communication terminal and the ground-side simulation device 3 to 1 mrad; S105: According to the scanning-gaze capture tracking process, the laser communication terminal starts scanning while the ground-side simulation device 3 gazes, and the test system monitoring camera monitors the scanning situation, and the time from the start of scanning is T0; S106: After the ground-side simulation device 3 receives the signal light from the laser communication terminal, it automatically adjusts its own direction according to the scanning-gaze capture tracking process so that its signal light is aimed at the laser communication terminal; S107: After the laser communication terminal receives the signal light from the ground-side simulation device 3, it stops scanning according to the scanning-staring capture tracking process, and automatically adjusts its own direction so that its signal light is aimed at the ground-side simulation device 3; the laser communication terminal and the ground-side simulation device stably track the signal light of the other party within their own precision tracking field of view, and the terminal is judged to have successfully captured, and the capture count is increased by 1. At this time, the timing value T1 is read, and T1-T0 is used as the capture time; if the terminal fails to complete the signal light capture within a certain time range T (T≥T1), it is judged that the terminal has failed to capture, and the capture count remains unchanged; S108: Repeat the above S101-S107 for at least 1000 times, record the number of captures and the capture time, divide the number of captures by the total number of tests as the corresponding capture success rate, and take the average value of the capture time as the corresponding capture success time.

[0037] Therefore, the performance of the capture times and the capture time can be tested by the above method.

[0038] It should be noted that the above four laser signals are used to calculate the capture success rate and capture success time respectively.

[0039] Specifically, in combination with the above-mentioned low-orbit star cluster inter-satellite laser communication networking test system, the tracking performance of the above-mentioned low-orbit star cluster inter-satellite laser communication networking is tested. Figure 4 As shown, including: S201: placing the laser communication terminal on the high-precision two-dimensional turntable 11, adjusting the two-dimensional turntable 11 and the fast reflection mirror respectively, so that the optical axes of the four laser communication terminals coincide with the optical axes of the corresponding test collimators 21, so that the laser communication beams completely enter the collimators 21; S202: Adjust the azimuth and elevation directions of the 4-way laser communication terminal, monitor the miss distance output of the tracking camera in real time, and make it stay within the capture field of view of the laser communication terminal; It should be noted that the above-mentioned fast-reflection mirror plays a role in controlling the direction of the light beam, and the tracking camera can calculate the centroid of the light spot in real time and output the miss distance, both of which are test auxiliary equipment; S203: The laser communication terminal is set to transmit 1540.56nm and receive 1563.05nm laser; the ground-side simulation device 3 is set to transmit 1563.05nm and receive 1540.56nm laser; S204: setting the initial bias values ​​of the laser communication terminal and the ground-side simulation device 3 to 1 mrad; S205: According to the scanning-gaze capture tracking process, the laser communication terminal starts scanning while the ground-side simulation device 3 gazes, and the test system monitoring camera monitors the scanning situation; S206: After the ground-side simulation device 3 receives the signal light from the laser communication terminal, it automatically adjusts its own direction according to the scanning-gaze capture tracking process so that its signal light is aimed at the laser communication terminal; S207: When the laser communication terminal receives the signal light from the ground-side simulation device 3, it stops scanning according to the scanning-gaze capture tracking process, and automatically adjusts its own direction so that its signal light is aimed at the ground-side simulation device 3; the laser communication terminal and the ground-side simulation device stably track the signal light of the other party within their own fine tracking field of view, or the fine tracking detector continuously detects the optical signal, and switches to the fine tracking mode; S208: The laser communication terminal and the ground-side simulation device 3 maintain stable tracking for 60 seconds; S209: Control the azimuth axis / pitch axis of the two-dimensional turntable 11 to move at a speed of 0.1° / s; S210: Record and capture the tracking camera tracking residual, stop recording after 5 minutes of movement, record the miss distance data during the tracking process and calculate the standard deviation as the corresponding tracking accuracy.

[0040] It should be noted that the above four laser signals are used to calculate tracking accuracy respectively.

[0041] Specifically, in combination with the above-mentioned low-orbit star cluster inter-satellite laser communication networking test system, the communication rate and packet loss rate of the above-mentioned low-orbit star cluster inter-satellite laser communication networking are tested, such as Figure 5 As shown, including: S301: placing the laser communication terminal on the high-precision two-dimensional turntable 11, and adjusting the two-dimensional turntable 11 and the fast reflection mirror respectively so that the optical axes of the four-way laser communication terminal coincide with the optical axes of the corresponding test collimator 21; S302: Adjust the azimuth and elevation directions of the 4-way laser communication terminal, monitor the miss distance output of the tracking camera in real time, and make it stay within the capture field of view of the laser communication terminal; S303: The laser communication terminal is set to transmit 1540.56nm and receive 1563.05nm laser; the ground-side simulation device 3 is set to transmit 1563.05nm and receive 1540.56nm laser; S304: setting the initial bias values ​​of the laser communication terminal and the ground-side simulation device 3 to 1 mrad; S305: According to the scanning-gaze capture tracking process shown in S205-S207, the laser communication terminal and the ground-side simulation device 3 maintain stable tracking for 60 seconds; S306: Setting the laser communication terminal signal light transmission power and link attenuation value; S307: restoring the laser communication terminal to a working state, wherein the laser communication terminal sends an optical signal and sets the communication rate to a preset value; S308: gradually adjusting the optical attenuator 22 so that the intensity of the optical signal received by the ground-side analog device 3 reaches a minimum value; S309: The ground-side simulation device 3 demodulates the received optical signal, continuously receives at least 100 million packets of data, and compares them with the transmitted data, counts the number of received error packets, and divides the number of received error packets by the number of transmitted packets as the corresponding packet loss rate; S310: Set different communication rates, repeat steps S307-S309, and record the corresponding packet loss rate and communication rate.

[0042] Therefore, the performance test of packet loss rate and communication rate can be completed through the above method.

[0043] It should be noted that the packet loss rates of the above four laser signals are calculated separately.

[0044] Specifically, in combination with the above-mentioned low-orbit star cluster inter-satellite laser communication networking test system, the delay performance of the above-mentioned low-orbit star cluster inter-satellite laser communication networking is tested. Figure 6As shown, including: S401: placing the laser communication terminal on the high-precision two-dimensional turntable 11, and adjusting the two-dimensional turntable 11 and the fast reflection mirror respectively so that the optical axes of the four-way laser communication terminal coincide with the optical axes of the corresponding test collimator 21; S402: Adjust the azimuth and elevation directions of the 4-way laser communication terminal, monitor the output of the tracking camera's miss distance in real time, and make it stay within the capture field of view of the laser communication terminal; S403: The laser communication terminal is set to transmit 1540.56nm and receive 1563.05nm laser; the ground-side simulation device 3 is set to transmit 1563.05nm and receive 1540.56nm laser; S404: setting the initial bias values ​​of the laser communication terminal and the ground-side simulation device 3 to 1 mrad; S405: According to the scanning-gaze capture tracking process, the laser communication terminal and the ground-side simulation device 3 are kept stably tracking for 60 seconds; S406: Connect four ground-side simulation devices 3 with a network cable, use the laser communication terminal and the ground-side simulation device 3 as nodes, set one of the ground-side simulation devices 3 as a master node, and set the IP addresses and initial states of the five nodes in the entire network; S407: Setting a node configuration table and a planned routing table of the current network according to the networking strategy; S408: Setting the routing management mode to ground centralized; S409: The service data packet to be forwarded through the inter-satellite laser link is notified through the master node, including unicast / multicast / broadcast mode, service priority, destination node information, etc.; S410: Verify whether the destination node has correctly received the service data packet, record the time when the service data packet is sent and received, and obtain the forwarding delay of the service data packet.

[0045] It should be noted that the above networking strategy includes how to transmit information between 5 nodes. The above destination node includes 5 nodes for networking communication, the master node plays a control role, and any two nodes among the 5 nodes can be sending or receiving nodes to transmit information.

[0046] In some optional implementations of this embodiment, the above networking strategies may include a centralized networking strategy and a distributed networking strategy, and the specific strategy selected is selected according to actual needs.

[0047] It should be noted that, in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In addition, "front", "back", "left", "right", "upper" and "lower" in this article are all referenced to the placement state shown in the accompanying drawings.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A low-orbit satellite cluster inter-satellite laser communication networking test system, characterized in that: include: A satellite attitude simulation device, wherein the satellite attitude simulation device is used to simulate the orbit, attitude and vibration changes of the satellite platform in the satellite laser link; A light beam far-field characteristic simulation device, which is used to simulate the distribution state and attenuation dynamic changes of the laser beam in the inter-satellite laser link of the low-orbit star cluster after long-distance transmission according to the laser signal; The ground-side simulation device is used to receive the satellite platform orbit, attitude and vibration change data simulated by the satellite attitude simulation device and the distribution state and attenuation dynamic change data of the laser beam after long-distance transmission simulated by the beam far-field characteristic simulation device, and cooperate with the laser communication terminal to complete the low-orbit star cluster inter-satellite laser communication networking performance test.

2. According to the low-orbit star cluster inter-satellite laser communication networking test system of claim 1, it is characterized in that: The satellite attitude simulation device comprises: A two-dimensional turntable, which is used to simulate the orbit and attitude changes of the satellite platform in the low-orbit constellation laser link; A oscillating platform is used to simulate the vibration changes of a satellite platform in a low-orbit constellation laser link.

3. According to claim 1, a low-orbit satellite cluster inter-satellite laser communication networking test system is characterized in that: The light beam far-field characteristic simulation device comprises: A collimator, which is used to obtain a parallel light beam to simulate the long-distance transmission of a laser beam; An optical attenuator, the optical attenuator is used to simulate the energy loss of interstellar laser beams during long-distance transmission; An optical platform, wherein the optical platform is used to support the collimator, the optical attenuator and other equipment and components used to support the low-orbit star cluster inter-satellite laser communication networking test.

4. According to claim 3, a low-orbit satellite cluster inter-satellite laser communication networking test system is characterized in that: The ground-side simulation equipment comprises: An optical antenna, wherein the optical antenna is used to receive a laser signal emitted by the laser communication terminal; An optical signal processing module, the optical signal processing module is used to convert the laser signal received by the optical antenna into an electrical signal, and to demodulate and decode the electrical signal; A beam quality analyzer, wherein the beam quality analyzer is used to detect the quality of the parallel light beam generated by the collimator; An optical power meter, the optical power meter is used to measure the laser power received by the optical antenna; A control module, wherein the control module is used to receive and process data from the satellite attitude simulation device, the light beam far-field characteristic simulation device and the ground-side simulation device. At the same time, the control module combines the orbit information, attitude information and vibration information of the satellite in the laser link simulated by the satellite attitude simulation device, the distribution state and attenuation dynamic changes of the laser beam in the low-orbit star cluster inter-satellite laser link simulated by the light beam far-field characteristic simulation device after long-distance transmission, and the information sent and received by the communication link to perform a performance test of the low-orbit star cluster inter-satellite laser communication network.

5. A method for testing the networking of low-orbit satellite cluster inter-satellite laser communication, characterized in that: include: Receive laser signals containing inter-satellite information of low-orbiting star clusters; Convert the received laser signal into an electrical signal to obtain the original information between the stars in the low-orbit star cluster; The performance of the low-orbit star cluster inter-satellite laser communication network is tested based on the original information obtained and the orbit information, attitude information, vibration information of the satellites in the simulated low-orbit star cluster laser link, as well as the distribution state and attenuation dynamic change information of the laser beam after long-distance transmission.

6. A method for testing low-orbit satellite cluster inter-satellite laser communication networking according to claim 5, characterized in that: The performance of the low-orbit constellation inter-satellite laser communication network tested includes: capture performance, tracking performance, communication rate, packet loss rate and delay performance.

7. A method for testing low-orbit satellite cluster inter-satellite laser communication networking according to claim 6, characterized in that: The test of the acquisition performance of the low-orbit constellation inter-satellite laser communication network includes: Initialize the laser communication terminal and the ground-side simulation equipment; When the ground-side simulation device receives the signal light emitted by the laser communication terminal, the ground-side simulation device is adjusted in a direction so that the signal light of the ground-side simulation device is aimed at the laser communication terminal; When the laser communication terminal receives the signal light of the analog device on the ground side, it adjusts its own direction so that the signal light of the laser communication terminal is aimed at the analog device on the ground side; When the laser communication terminal and the ground-side simulation equipment stably track the signal light of the other party within their own precision tracking field of view or the precision tracking detector continuously detects the optical signal, they switch to the precision tracking mode. At this time, the terminal is judged to have successfully captured, and the number of captures is increased by 1. At this time, the timing value T1 is read, and T1-T0 is used as the capture time, and T0 represents the start time of self-scanning; multiple captures are performed, and the number of captures and capture times are recorded at the same time. The number of captures is divided by the total number of tests as the corresponding capture success rate, and the average capture time is taken as the corresponding capture success time.

8. The method for testing the networking of low-orbit satellite cluster inter-satellite laser communication according to claim 6, characterized in that: Testing of tracking performance of intersatellite laser communication network of low-orbit constellation includes: Initialize the laser communication terminal and the ground-side simulation equipment; When the ground-side simulation device receives the signal light of the laser communication terminal, the ground-side simulation device adjusts its own direction so that the signal light of the ground-side simulation device is aimed at the laser communication terminal; When the laser communication terminal receives the signal light from the ground-side simulation device, the laser communication terminal stops scanning and automatically adjusts its own direction so that the signal light of the laser communication terminal is aimed at the ground-side simulation device; the laser communication terminal and the ground-side simulation device stably track the signal light of the other party within their own precision tracking field of view or the precision tracking detector continuously detects the optical signal, and switches to the precision tracking mode; The laser communication terminal and the ground-side simulation equipment maintain stable tracking for 60 seconds; The laser communication terminal is controlled to rotate at a preset speed, the tracking residual of the capture tracking camera is recorded, the recording is stopped after the preset movement time, the off-target amount data during the tracking process is recorded and the standard deviation is calculated as the corresponding tracking accuracy.

9. The method for testing the networking of low-orbit satellite cluster inter-satellite laser communication according to claim 6, characterized in that: The communication rate and packet loss rate of the low-orbit satellite inter-satellite laser communication network are tested including: Initialize the laser communication terminal and the ground-side simulation equipment; Keep the laser communication terminal and the ground-side simulation equipment stably tracked for 60 seconds; Set the signal light transmission power and link attenuation value of the laser communication terminal; The laser communication terminal is restored to a working state, the laser communication terminal sends an optical signal and sets the communication rate to a preset value; Adjust the optical attenuator to minimize the intensity of the optical signal received by the analog device on the ground side; The analog device on the ground side demodulates the received optical signal, compares it with the transmitted data, and counts the number of received error packets; Set different communication rates and calculate the packet loss rates corresponding to different communication rates.

10. The method for testing the networking of low-orbit satellite cluster inter-satellite laser communication according to claim 6, characterized in that: The delay performance test of the low-orbit constellation inter-satellite laser communication network includes: Initialize the laser communication terminal and the ground-side simulation equipment; The laser communication terminal and the ground-side simulation equipment maintain stable tracking for 60 seconds; Use network cables to connect multiple ground-side simulation devices, use the laser communication terminal and the ground-side simulation devices as nodes, set one of the ground-side simulation devices as the master node, and set the IP addresses and initial states of multiple nodes; Set the node configuration table, planning routing table and routing management mode of the current network according to the networking strategy; The service data packets that need to be forwarded through the inter-satellite laser link are registered through the master node; Verify whether the destination node has correctly received the service data packet, record the time when the service data packet is sent and received, and obtain the service data packet forwarding delay performance.

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