Satellite data transmission system and method

Abstract

The application relates to a satellite data transmission system and method, and relates to the technical field of satellite communication.The system comprises integrated terminal one, integrated terminal two, a switch matrix, phased array antenna one and phased array antenna two.The switch matrix receives two-way radio frequency signals of the integrated terminal one and the integrated terminal two, carries out filtering treatment respectively, and is switched through a coaxial switch to be transmitted to the phased array antenna one or the phased array antenna two.The phased array antenna one receives the radio frequency signals sent by the switch matrix, carries out amplification, and radiates the signals in a dual polarization mode.The phased array antenna one and the phased array antenna two are installed on the two sides of the satellite to the ground in an axial symmetry mode with the satellite flight direction as the axis, so that the problem of lens barrel shielding is solved.The system realizes cross backup of two sets of integrated terminals and two sets of phased array antennas, and improves the reliability and availability.The system adopts a dual-frequency dual-polarization mode, realizes double-channel data transmission, and effectively avoids the signal transmission problem caused by poor polarization isolation of the phased array.

Description

Technical Field

[0001] This invention relates to the field of satellite communication technology, and in particular to a satellite data transmission system and method. Background Technology

[0002] The camera system of an optical satellite has a huge telescope tube, which severely obstructs the field of view of the data transmission antenna. Typically, data transmission systems use a mechanically rotating parabolic antenna, which is installed at the farthest end away from the telescope tube. When the antenna is working, the mechanical rotating mechanism further extends the parabolic antenna away from the telescope tube to solve the problem of telescope tube obstruction. However, the mechanical rotating structure is heavy and bulky, which puts strict requirements on the weight, size and installation layout of small satellites. Summary of the Invention

[0003] To address the technical problems existing in the prior art, the present invention aims to provide a satellite data transmission system and method that enables dual-channel data transmission, reduces product weight and volume, lowers requirements for overall satellite installation layout, improves system reliability and availability, solves the problem of mirror tube obstruction, and effectively avoids signal transmission problems caused by poor phased array polarization isolation.

[0004] To achieve the above-mentioned objectives, the present invention provides a satellite data transmission system and method, comprising:

[0005] Integrated terminal 1, integrated terminal 2, switch matrix, phased array antenna 1 and phased array antenna 2;

[0006] The integrated terminal one and integrated terminal two are in the same state and serve as cold backups for each other;

[0007] The phased array antenna one and phased array antenna two are in the same state and serve as hot backups for each other;

[0008] The phased array antenna one and phased array antenna two are installed on both sides of the satellite relative to the ground with the satellite's flight direction as the axis.

[0009] The integrated terminal receives, processes, compresses, and stores raw image data from multiple satellite payloads, and performs signal conditioning and modulation on the stored data to generate radio frequency signals that are sent to the switching matrix.

[0010] The integrated terminal receives satellite remote control commands via a data bus to parse and execute the remote control commands, and the integrated terminal also collects telemetry data from the data acquisition device and sends it to the satellite service subsystem via the data bus.

[0011] The satellite service subsystem is the satellite center computer responsible for the management and control of the satellite;

[0012] The switch matrix receives two radio frequency signals from integrated terminal one and integrated terminal two and performs filtering processing on them respectively. The switch matrix is ​​switched by a coaxial switch to transmit to phased array antenna one or phased array antenna two.

[0013] The switch matrix receives satellite remote control commands to achieve coaxial switch switching;

[0014] The phased array antenna receives and amplifies the radio frequency signal transmitted by the switching matrix, and radiates the signal in a dual-polarized manner.

[0015] The phased array antenna 1 communicates with the satellite service subsystem via a data bus and receives remote control commands sent by the satellite service subsystem. The phased array antenna 1 also receives satellite broadcast data required for calculating beam pointing and collects its own telemetry data to send to the satellite service subsystem.

[0016] Furthermore, based on the satellite data broadcast by the satellite service subsystem and combined with the data from the data transmission receiving station, the two-dimensional pointing angles of phased array antenna one and phased array antenna two are calculated to control the beam pointing of phased array antenna one and phased array antenna two and realize the pointing tracking and communication of the antenna beam to the ground receiving station.

[0017] The data bus receives and stores longitude, latitude, and altitude data from ground-based data transmission receiving stations to calculate antenna beam pointing.

[0018] Furthermore, the phased array antenna one and phased array antenna two have a frequency point difference of N Hz, where N = 150 MHz.

[0019] Furthermore, the angles between the phased array antenna one, the phased array antenna two, and the direction of the nadir point are...

[0020] Furthermore, the data storage capacity of both the integrated terminal one and the integrated terminal two is greater than 4Tbits.

[0021] Furthermore, the interfaces between the integrated terminal 1, integrated terminal 2 and the load subsystem both adopt CXP interface and LVDS interface.

[0022] A transmission method based on a satellite data transmission system includes the following steps:

[0023] Step 1: Integrated Terminal 1 and Integrated Terminal 2 receive payload data, buffer it, and complete the addition of synchronization words, CRC check, LDPC encoding, and scrambling of the payload data. After modulation, the data is transmitted to the ground equipment via the space-ground channel.

[0024] Step 2: After demodulation, the ground equipment performs demodulation, frame synchronization, descrambling, and decoding, and then transmits the data frame by frame to the backend equipment.

[0025] Step 3: Integrated Terminal 1 and Integrated Terminal 2 complete the modulation of the baseband signal;

[0026] Step 4: Phased array antenna 1 and phased array antenna 2 are injected with the data transmission receiving station site through ground injection.

[0027] Step 5: Phased array antenna one and phased array antenna two achieve radio frequency signal input of integrated terminal one or integrated terminal two by switching the switch matrix;

[0028] Step Six: Phased array antenna one and phased array antenna two are powered on simultaneously to receive satellite time and position information broadcast by the entire satellite bus. Combined with the preset data transmission ground receiving station address information, the antenna pointing of phased array antenna one and phased array antenna two is calculated in real time to complete beam control and meet the real-time data transmission requirements during the attitude maneuver of the entire satellite.

[0029] Furthermore, the switching matrix is ​​switched by the satellite control command so that only one of the phased array antennas, or phased array antenna two, has radio frequency signal input, and that antenna is visible to the ground data receiving station.

[0030] Furthermore, the modulation scheme used by the integrated terminal one and the integrated terminal two is QPSK, and the transmission rate is 2×450Mbps, 2×300Mbps, or 2×150Mbps.

[0031] Furthermore, the phased array antenna one and the phased array antenna two support multiple sets of data transmission ground station sites, with the number of data transmission ground station sites being no more than 30.

[0032] Compared with the prior art, the present invention has the following advantages:

[0033] 1. This invention uses a switching matrix to switch between two phased array antennas, realizing cross-backup of two integrated terminals and two phased array antennas, thereby improving system reliability and availability;

[0034] 2. This invention uses two phased array antennas installed at an angle, that is, they are installed on both sides of the satellite relative to the ground with the direction of satellite flight as the axis, thus solving the problem of obstruction by the telescope tube;

[0035] 3. This invention adopts a dual-frequency dual-polarization method to realize dual-channel data transmission, which can effectively avoid signal transmission problems caused by poor polarization isolation of the phased array. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without creative effort.

[0037] Figure 1 This invention provides a block diagram of a satellite data transmission system. Detailed Implementation

[0038] To address the technical problems existing in the prior art, the present invention provides a satellite data transmission system that enables dual-channel data transmission, reduces product weight and volume, lowers requirements for overall satellite installation layout, improves system reliability and availability, solves the problem of obstruction by the telescope tube, and can effectively avoid signal transmission problems caused by poor phased array polarization isolation.

[0039] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0040] See Figure 1 :

[0041] A satellite data transmission system includes an integrated terminal 1, an integrated terminal 2, a switch matrix, a phased array antenna 1, and a phased array antenna 2.

[0042] Integrated Terminal 1 and Integrated Terminal 2 are in the same state and serve as cold backups for each other;

[0043] Phased array antenna one and phased array antenna two are in the same state and serve as hot backups for each other;

[0044] Phased array antenna one and phased array antenna two are installed on both sides of the satellite relative to the ground with the satellite's flight direction as the axis.

[0045] The integrated terminal receives, processes, compresses, and stores raw image data from multiple satellite payloads, and performs signal conditioning and modulation on the stored data to generate radio frequency signals that are sent to the switching matrix.

[0046] The integrated terminal receives satellite remote control commands via a data bus to parse and execute the remote control commands, and the integrated terminal also collects telemetry data from the equipment and sends it to the satellite service subsystem via the data bus.

[0047] The satellite operations subsystem is the central computer for satellite management and control.

[0048] The switch matrix receives two radio frequency signals from integrated terminal one and integrated terminal two and performs filtering processing on them respectively. The switch matrix is ​​switched by a coaxial switch to transmit the signals to phased array antenna one or phased array antenna two.

[0049] The switch matrix receives satellite remote control commands to achieve coaxial switch switching;

[0050] A phased array antenna receives and amplifies radio frequency signals transmitted by a switching matrix, and radiates the signals in a dual-polarized manner.

[0051] Phased array antenna 1 communicates with the satellite service subsystem via a data bus and receives remote control commands sent by the satellite service subsystem. It also receives satellite broadcast data required for beam pointing calculation and collects its own telemetry data to send to the satellite service subsystem.

[0052] Based on the satellite data broadcast by the Star Service Subsystem and combined with the data from the data transmission receiving station, the two-dimensional pointing angles of phased array antenna one and phased array antenna two are calculated to control the beam pointing of phased array antenna one and phased array antenna two and realize the pointing tracking and communication of the antenna beam to the ground receiving station.

[0053] The system receives and stores longitude, latitude, and altitude data from ground-based data transmission stations via a data bus for use in calculating antenna beam pointing.

[0054] The two frequency points of phased array antenna one and phased array antenna two are separated by N Hertz, where N = 150 MHz.

[0055] The angles between phased array antenna 1, phased array antenna 2, and the direction of the nadir point are:

[0056] Both integrated terminal one and integrated terminal two have a data storage capacity of more than 4Tbits.

[0057] Both the integrated terminal 1 and integrated terminal 2 use CXP and LVDS interfaces with the load subsystem.

[0058] The data flow operation process of integrated terminal 1 and integrated terminal 2 is as follows: receiving payload data, buffering it, and completing the addition of synchronization words, CRC check, LDPC encoding, and scrambling of the payload data. After modulation, it is transmitted to the ground equipment through the space-ground channel. After demodulation, the ground equipment performs demodulation, frame synchronization, descrambling, and decoding, and transmits the data to the back-end equipment frame by frame. Integrated terminal 1 and integrated terminal 2 complete the modulation of the baseband signal. The modulation mode is QPSK, and the transmission rate supports three levels: 2×450Mbps, 2×300Mbps, and 2×150Mbps.

[0059] Phased array antenna one and phased array antenna two can inject data transmission receiving station sites through ground injection, and can support up to 30 data transmission ground station sites.

[0060] Phased array antenna one and phased array antenna two achieve RF signal input to integrated terminal one or integrated terminal two through switching of the switching matrix. In order to meet the real-time data transmission during satellite attitude maneuvering, phased array antenna two and phased array antenna one can be powered on simultaneously to receive satellite time and position information broadcast by the satellite bus. Combined with the preset data transmission ground receiving station address information, the antenna pointing of phased array antenna one and phased array antenna two is calculated in real time to complete beam control. However, only one antenna of phased array antenna one and phased array antenna two can receive RF signals. Specifically, the switching matrix is ​​switched through satellite commands to ensure that only one antenna of phased array antenna one or phased array antenna two has RF signal input. At the same time, it can be ensured that the secondary antenna is visible to the ground data transmission receiving station.

[0061] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Unless otherwise specified, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0062] Finally, it should be noted that the above description represents a preferred embodiment of the present invention. It should be pointed out that although preferred embodiments have been described, those skilled in the art, once they understand the basic inventive concept of the present invention, can make various improvements and modifications without departing from the principles described herein. These improvements and modifications should also be considered within the scope of protection of the present invention. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the embodiments of the present invention.

Claims

1. A satellite data transmission system, characterized in that, include: Integrated terminal 1, integrated terminal 2, switch matrix, phased array antenna 1 and phased array antenna 2; The integrated terminal one and integrated terminal two are in the same device state and serve as cold backups for each other; The phased array antenna one and phased array antenna two are in the same state and serve as hot backups for each other; The phased array antenna one and phased array antenna two are installed on both sides of the satellite relative to the ground with the satellite's flight direction as the axis. The integrated terminal receives, processes, compresses, and stores raw image data from multiple satellite payloads, and performs signal conditioning and modulation on the stored data to generate radio frequency signals that are sent to the switching matrix. The integrated terminal receives satellite remote control commands via a data bus to parse and execute the remote control commands, and the integrated terminal also collects telemetry data from the data acquisition device and sends it to the satellite service subsystem via the data bus. The satellite service subsystem is the satellite center computer responsible for the management and control of the satellite; The switch matrix receives two radio frequency signals from integrated terminal one and integrated terminal two and performs filtering processing on them respectively. The switch matrix is ​​switched by a coaxial switch to transmit to phased array antenna one or phased array antenna two. The switch matrix receives satellite remote control commands to achieve coaxial switch switching; The phased array antenna receives and amplifies the radio frequency signal transmitted by the switching matrix, and radiates the signal in a dual-polarized manner. The phased array antenna 1 communicates with the satellite service subsystem via a data bus and receives remote control commands sent by the satellite service subsystem. The phased array antenna 1 also receives satellite broadcast data required for calculating beam pointing and collects its own telemetry data to send to the satellite service subsystem. Based on the satellite data broadcast by the Star Service Subsystem and combined with the data from the data transmission receiving station, the two-dimensional pointing angles of phased array antenna one and phased array antenna two are calculated to control the beam pointing of phased array antenna one and phased array antenna two and realize the pointing tracking and communication of the antenna beam to the ground receiving station. The data bus receives and stores longitude, latitude, and altitude data from ground-based data transmission receiving stations to calculate antenna beam pointing.

2. The satellite data transmission system according to claim 1, characterized in that: The phased array antenna one and phased array antenna two have a frequency point difference of N Hertz, where N = 150 MHz.

3. A satellite data transmission system according to claim 1, characterized in that: The angle between phased array antenna one, phased array antenna two, and the direction of the nadir point is... , =40°.

4. A satellite data transmission system according to claim 1, characterized in that: The data storage capacity of both integrated terminal one and integrated terminal two is greater than 4Tbits.

5. A satellite data transmission system according to claim 1, characterized in that: The interfaces between the integrated terminal 1, integrated terminal 2 and the load subsystem both adopt CXP interface and LVDS interface.

6. A satellite data transmission method, implemented based on the satellite data transmission system according to any one of claims 1-5, characterized in that, Includes the following steps: Step 1: Integrated Terminal 1 and Integrated Terminal 2 receive payload data, buffer it, and complete the addition of synchronization words, CRC check, LDPC encoding, and scrambling of the payload data. After modulation, the data is transmitted to the ground equipment via the space-ground channel. Step 2: After demodulation, the ground equipment performs demodulation, frame synchronization, descrambling, and decoding, and then transmits the data frame by frame to the backend equipment. Step 3: Integrated Terminal 1 and Integrated Terminal 2 complete the modulation of the baseband signal; Step 4: Phased array antenna 1 and phased array antenna 2 are injected with the data transmission receiving station site through ground injection. Step 5: Phased array antenna one and phased array antenna two achieve radio frequency signal input of integrated terminal one or integrated terminal two by switching the switch matrix; Step Six: Phased array antenna one and phased array antenna two are powered on simultaneously to receive satellite time and position information broadcast by the entire satellite bus. Combined with the preset data transmission ground receiving station address information, the antenna pointing of phased array antenna one and phased array antenna two is calculated in real time to complete beam control and meet the real-time data transmission requirements during the attitude maneuver of the entire satellite.

7. A satellite data transmission method according to claim 6, characterized in that: The switching matrix is ​​switched by the whole satellite command so that only one of the phased array antennas, or phased array antenna one or phased array antenna two, has radio frequency signal input, and that antenna is visible to the ground data receiving station.

8. A satellite data transmission method according to claim 6, characterized in that: The modulation scheme used by the integrated terminal one and integrated terminal two is QPSK, and the transmission rate is 2×450Mbps, 2×300Mbps, or 2×150Mbps.

9. A satellite data transmission method according to claim 6, characterized in that: The phased array antenna one and phased array antenna two support multiple sets of data transmission ground station sites, with the number of data transmission ground station sites not exceeding 30.

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