Miniature gateway station system of low-orbit satellite

Abstract

In the low-orbit satellite miniature gateway station system, an antenna servo subsystem captures and tracks specific target satellites in a whole airspace range and transmits and receives signals in an uplink mode and in a downlink mode; the radio frequency subsystem realizes up-conversion and power amplification of an uplink signal, amplification and down-conversion of a downlink signal and down-conversion of an uplink calibration signal; the baseband subsystem realizes synchronization, demodulation and decoding of downlink feed signals and coding and modulation of uplink feed signals; the time-frequency subsystem provides a 10MHz reference source and unified time reference information, and carries out distribution according to the requirements of all devices of a gateway station. The in-station network management subsystem is used for monitoring and controlling equipment of the gateway station; and the subsystem is ensured to provide safe and reliable environmental conditions, and is used for ensuring normal work and daily overhaul and maintenance of each device of the gateway station. The system is complete in function, high in integration level, convenient to transport, high in environmental adaptability and low in station building cost, and has measurement and control along with the road and self-tracking capability for specific target satellites passing at any angle.

Description

Technical Field

[0001] The present invention belongs to the field of satellite communication technology, and in particular relates to a low-orbit satellite micro-gateway system. Background Art

[0002] Low Earth Orbit (LEO) satellites are satellites operating at altitudes significantly lower than medium Earth orbit and geostationary orbit. These satellites typically hover approximately 500 to 2000 kilometers above the Earth's surface. They offer minimal space transmission losses, high bandwidth, and low latency. Their coverage area moves rapidly across the Earth's surface, and a constellation of multiple satellites can achieve global coverage.

[0003] A typical low-orbit satellite communication system mainly consists of three parts: space segment, ground segment and user segment.

[0004] Space segment: Low-orbit constellations comprise dozens, hundreds, or even more small satellites. These constellations often employ a multi-layered hybrid system of sub-constellations at varying orbital altitudes and inclinations. Low-orbit communication satellites serve as access nodes for the space network, functioning as space-based mobile base stations.

[0005] The ground segment includes a gateway, an integrated operations and control management system, and infrastructure connecting to the ground core network. This segment primarily manages and operates the satellite constellation. The gateway also serves as a gateway between the satellite and ground networks. Data is connected to the ground network through the gateway, converting between the satellite-to-ground air interface communication protocol and the network protocol, enabling access to ground network resources.

[0006] User segment: mainly includes vehicle-mounted stations, ship-mounted stations, airborne terminals, portable terminals, computers, and mobile terminals. User terminals can serve as access points to establish a local area network and connect user devices to the network.

[0007] Among them, the ground segment gateway station is crucial as a transit center for satellite-to-ground information transmission and data exchange. The payload of low-orbit communication satellites is divided into user beams and feed beams. User terminals need to operate within the coverage of the user beams, and the gateway stations need to operate under the coverage of the feed beams. For users to achieve end-to-end communication, data must be transferred through the affiliated gateway station. Among them, a gateway terminal can only point to and track one satellite at a time. However, due to the large number of satellites in the low-orbit constellation, there may be multiple satellites passing by at the same time. At this time, multiple gateway terminals are required to complete the transmission and reception of satellite signals, and finally a distributed gateway station deployment with multiple terminals is formed, which is uniformly managed by the network management software of the operation and control center. The low-orbit constellation satellite beams have global coverage, and gateway stations must also be built globally.

[0008] China's low-orbit satellite communication system is currently in the early stages of development and construction. Existing low-orbit satellite gateways are all traditional gateways, largely modeled after high-orbit satellite gateways. They haven't been specifically designed to take into account the construction characteristics and application requirements of low-orbit satellites. The main problems with existing traditional gateways are:

[0009] The gateway station has a large overall structure;

[0010] The Xinguan Station occupies a large area;

[0011] The entire gateway is heavy;

[0012] The integration of gateway stations is low;

[0013] The gateway antenna cannot track a specific target satellite in any direction;

[0014] It is inconvenient to transport the entire machine at the customs station.

[0015] In order to solve the above problems that currently occur in low-orbit satellite gateway stations, targeted system design of the gateway stations is required. Summary of the Invention

[0016] The purpose of the present invention is to provide a low-orbit satellite micro-gateway system. The micro-gateway of the present invention has complete functions, high integration, convenient transportation, strong environmental adaptability, low station construction cost, and has the ability to measure and control along the way and self-track specific target satellites passing at any angle.

[0017] The technical solution adopted by the present invention is a low-orbit satellite micro-gateway system, including a servo feed subsystem, a radio frequency subsystem, a baseband subsystem, a time and frequency subsystem, an in-station network management subsystem, and a security subsystem;

[0018] The servo-feedback system realizes the capture and tracking of specific target satellites in the entire airspace, as well as the uplink transmission and downlink reception of signals;

[0019] The radio frequency subsystem realizes up-conversion and power amplification of uplink signals, signal amplification and down-conversion of downlink signals, and down-conversion of uplink calibration signals;

[0020] The baseband subsystem realizes synchronization, demodulation, decoding of downlink feed signals and encoding and modulation of uplink feed signals;

[0021] The time-frequency subsystem provides a 10MHz reference source and unified time reference information, and distributes it according to the needs of each device in the gateway station;

[0022] The in-station network management subsystem monitors and controls all devices at the gateway station, connecting all monitored devices via Ethernet switches and terminal servers;

[0023] The security subsystem provides a safe and reliable environment to ensure the normal operation and routine inspection and maintenance of all equipment in the gateway station.

[0024] Furthermore, the antenna servo feed subsystem includes an antenna feed subsystem, a mechanical structure subsystem, a servo control subsystem and a tracking subsystem;

[0025] The antenna subsystem provides a radio frequency channel, generates the sum and difference signals required for self-tracking, and completes the reception and transmission of microwave signals;

[0026] The mechanical structure subsystem achieves miniaturization of the gateway antenna structure by adjusting the antenna focal diameter ratio, changing the antenna mount form, and rationally arranging the installation position of the gateway equipment;

[0027] The servo control subsystem completes the drive control and maintenance of the gateway antenna, and realizes the pointing and capture of the specific target satellite;

[0028] The tracking subsystem completes the amplification and down-conversion of the difference path signal, and provides the antenna azimuth, pitch error voltage, AGC value and lock indication to the regional control unit through the tracking receiver, thereby realizing the self-tracking of the gateway station antenna.

[0029] Furthermore, the radio frequency subsystem includes a BUC device, an LNB device and a calibration downconverter; the BUC device up-converts the intermediate frequency signal from the baseband and outputs it at high power; the LNB device amplifies and down-converts the radio frequency signal received by the gateway antenna and outputs it; and the calibration downconverter converts the uplink frequency to the downlink frequency.

[0030] Furthermore, the baseband subsystem includes a power feeding baseband device and a measurement and control baseband device; the power feeding baseband device completes the encoding / modulation and demodulation / decoding / synchronization of the power feeding data to realize high code rate signal processing; the measurement and control baseband device completes the encoding / modulation of the remote control data and the demodulation / decoding / synchronization of the telemetry signal, and has dual-channel single pulse tracking capability.

[0031] Furthermore, the time and frequency division system includes a GNSS satellite receiving antenna and a positioning and direction-direction timing device; the GNSS satellite receiving antenna accurately receives GNSS satellite signals and has good anti-interference performance; the positioning and direction-direction timing device locks and tames the high-stability crystal oscillator inside the machine to achieve complete synchronization of the local clock with the satellite clock received by the receiver.

[0032] Furthermore, the in-site network management subsystem includes application software and hardware equipment; the application software is deployed on the in-site server using a B / S architecture to realize site topology display, equipment status monitoring and equipment control instruction issuance; the hardware equipment provides an installation platform for the deployment of various system software and has computing and storage capabilities.

[0033] Furthermore, the security subsystem includes security control equipment, switching and transmission equipment, environmental control and protection equipment, and an inspection door; the security control equipment provides basic monitoring and safety protection capabilities; the switching and transmission equipment provides data exchange and data transmission capabilities; the environmental control and protection equipment provides protection conditions and temperature and humidity environment; the inspection door facilitates maintenance personnel to enter the antenna cover through the inspection door to perform daily maintenance and inspection of the gateway equipment.

[0034] The beneficial effects of the present invention are:

[0035] Systematization: Through the deployment of multiple antennas at the same site and the comprehensive software and hardware configuration of six subsystems, it is possible to simultaneously transmit and receive feed beams for multiple transiting satellites. By sharing antennas and RF channels and configuring a measurement and control baseband, the gateway station can have on-link measurement and control capabilities, ultimately making it a new type of full-function gateway station.

[0036] Integration: By scientifically arranging the equipment of each gateway station within a limited space, a high degree of integration of the entire gateway station can be achieved.

[0037] Small envelope: While ensuring that the antenna diameter of the gateway station remains unchanged, the overall envelope size of the gateway station can be reduced by changing the antenna mount structure, adjusting the antenna focal diameter ratio, and lowering the antenna height.

[0038] Strong adaptability: By configuring temperature and humidity sensors, heaters and coolers, etc., the entire gateway equipment can have good environmental adaptability.

[0039] High security: By configuring monitoring equipment, the operation status of each gateway device in the antenna cover can be observed, improving the security of the entire gateway.

[0040] Convenient transportation: The optimized design makes the size of the gateway station suitable for road and container transportation, and the entire station can be transported by sea, land and air. It also eliminates the need for disassembly, assembly and retesting of the gateway station equipment, reducing workload.

[0041] Reduce costs: Through the above design, the area occupied by the gateway station can be reduced, the staffing can be reduced, the number of transportation times can be reduced, and ultimately the cost of station construction can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is a schematic diagram of the layout of the gateway equipment of the present invention;

[0043] Among them: 1. Feed sleeve; 2. Observation and maintenance port; 3. Antenna mount; 4. Column; 5. Junction box; 6. Antenna chassis; 7. Aerial plug; 8. Radome; 9. Maintenance door; 10. Heater; 11. Lighting equipment; 12. Network camera; 13. Temperature and humidity sensor; 14. Air conditioning (refrigeration) outdoor unit; 15. Air conditioning (refrigeration) indoor unit. DETAILED DESCRIPTION

[0044] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the technical solutions of the present invention will be further described in detail below with reference to the accompanying drawings.

[0045] A low-orbit satellite micro-gateway system includes a servo feed subsystem, a radio frequency subsystem, a baseband subsystem, a time-frequency subsystem, an in-station network management subsystem, and a security subsystem.

[0046] 1. Antenna Feedback System

[0047] The servo-aerial feed system can capture and track specific target satellites (low-orbit satellites) in the entire airspace, as well as transmit and receive radio frequency signals uplink and downlink.

[0048] The antenna servo feed subsystem includes the antenna feed subsystem, mechanical structure subsystem, servo control subsystem and tracking subsystem.

[0049] 1. Antenna subsystem

[0050] The antenna subsystem provides the RF channel, generates the sum and difference signals required for self-tracking, and completes the reception and transmission of microwave signals.

[0051] The antenna subsystem primarily consists of a radiator, a TE21 mode coupler, a differential channel waveguide synthesis network, a baffle circular polarizer, a waveguide switch, and waveguide structural connectors. The radiator utilizes a corrugated horn, offering excellent amplitude and phase pattern equalization for both TE11 and TE21 modes, as well as low sidelobe levels and low cross-polarization performance.

[0052] 2. Mechanical structure subsystem

[0053] The mechanical structure subsystem achieves miniaturization of the gateway station antenna structure by adjusting the antenna focal diameter ratio, changing the antenna mount form, and rationally arranging the installation location of the gateway station equipment.

[0054] The mechanical structure subsystem mainly includes the antenna main / sub-reflector, feed tube and sub-surface support, antenna mount, column and limit protection device.

[0055] 3. Servo control subsystem

[0056] The servo control subsystem completes the drive control and maintenance of the gateway antenna, and realizes the pointing and capture of specific target satellites.

[0057] The servo control subsystem consists of a control circuit component, a motor drive component, an angle measurement component, and a power supply component. The control circuit component, as the core component of the entire servo control subsystem, is responsible for sensor acquisition, calculations, and motor control. The motor drive component, composed of a motor and driver, together forms the actuator for the gateway antenna's rotation. The angle measurement component consists of Hall effect switches and angle encoders, which work together to accurately output the angles of each axis of the gateway antenna.

[0058] 4. Tracking subsystem

[0059] The tracking subsystem completes the amplification and down-conversion of the difference path signal, and provides the antenna azimuth, pitch error voltage, AGC value and lock indication to the regional control unit.

[0060] The tracking subsystem consists of a differential path low noise down converter and a tracking receiver.

[0061] The difference path low noise down converter realizes the amplification and down conversion of the difference path signal.

[0062] The tracking receiver (measurement and control baseband equipment) provides the regional control unit with antenna azimuth, pitch error voltage, AGC (automatic gain control) value and lock indication, and together with the antenna control drive unit completes self-tracking of a specific target satellite.

[0063] By optimizing the antenna structure of the gateway station and the scientific layout of the gateway station equipment, the miniaturization of the gateway station can be achieved. Figure 1 The specific contents are as follows:

[0064] Adjust the antenna focal ratio, change the antenna axial size, and reduce the rotation envelope of the gateway antenna.

[0065] The feeder network, differential network and LNB equipment are installed in the feed sleeve 1 to improve the space utilization inside the sleeve. In order to facilitate the installation and maintenance of waveguides, the feed sleeve 1 has observation and maintenance ports 2 on both sides of the feed and LNB equipment installation positions.

[0066] Antenna mount 3 utilizes an AET triaxial mount, with the elevation axis E, azimuth axis A, and tilt axis T arranged from top to bottom. The elevation axis E utilizes a Y-shaped mount, which shifts the antenna mounting surface back, lowering the antenna installation height and minimizing the gateway antenna's motion envelope. This creates a bow-shaped antenna backrest. The antenna backrest is used to mount the power amplifier and calibration converter. The amplifier's RF output port is positioned close to the outlet of the feed sleeve 1, shortening the transmit waveguide and reducing link loss. The power amplifier and calibration converter also serve as counterweights for the antenna's elevation.

[0067] The interior of pitch axis E provides ample space for the pitch motor, driver, and encoder. The pitch motor is mounted on the upper left side of the Y-shaped mount. The left wall cavity provides routing and passage for the pitch motor's power and control cables. The right wall cavity provides routing and passage for the RF cables, power cables, and control cables for the LNB, power amplifier, and calibration converter. The pitch driver and encoder unit are mounted within the short crossbar of the Y-shaped mount.

[0068] In order to facilitate the smooth leading of the cables above the azimuth axis A to the antenna chassis 6, in the present invention, both the azimuth motor and the tilt motor are hollow motors, and all cables of the pitch motor and all cables of the radio frequency equipment can be smoothly led to the column 4 through the hole in the middle of the hollow motor.

[0069] The column 4 is connected to the antenna chassis 6. A junction box 5 is reserved at the bottom of the column 4. The supporting cables of all equipment on the gateway station antenna are gathered in the junction box 5. The external cables are connected to the aerial socket 7 reserved on the antenna chassis 6 through the junction box 5.

[0070] The antenna's primary reflector is made of carbon fiber, ensuring both precision and lightweight design. The primary reflector achieves an RMS accuracy of 0.2mm or less. The secondary reflector is cast from aluminum and precision-machined using a CNC lathe after heat treatment, achieving an RMS accuracy of 0.1mm or less.

[0071] The servo-satellite feed system of the present invention can achieve movement within the range of -355° to 355° in azimuth, 0° to 90° in pitch, and 0° to 360° in tilt, enabling pointing and tracking of specific target satellites (low-orbit constellations) in any direction. The system weighs ≤180kg and can be transported by road, air, or container.

[0072] 2. RF Subsystem

[0073] The RF subsystem realizes up-conversion and power amplification of uplink signals, signal amplification and down-conversion of downlink signals, and down-conversion of uplink calibration signals.

[0074] The RF subsystem includes BUC equipment, LNB equipment (sum path / difference path) and calibration downconverter.

[0075] 1. BUC equipment

[0076] The BUC device up-converts the intermediate frequency signal from the baseband and outputs it at high power.

[0077] 2. LNB equipment

[0078] The LNB device amplifies and down-converts the RF signal received by the gateway antenna.

[0079] 3. Calibrate the downconverter

[0080] The downconverter is calibrated to convert the upstream frequency to the downstream frequency.

[0081] 3. Baseband Subsystem

[0082] The baseband subsystem realizes the synchronization, demodulation, decoding of the downlink feed signal and the encoding and modulation of the uplink feed signal. It has the function of remotely controlling the small loop detection of the uplink signal and the ability to interact with the operation control center.

[0083] The baseband subsystem includes power supply baseband equipment and measurement and control baseband equipment.

[0084] 1. Feed baseband equipment

[0085] The feeding baseband equipment completes the encoding / modulation and demodulation / decoding / synchronization of the feeding data to achieve high code rate signal processing.

[0086] The feed baseband equipment primarily consists of a frequency conversion processing board, a baseband processing board, a power supply module, a frequency synthesizer module, and a switch board module. It utilizes a high-speed ADC (analog-to-digital converter), DAC (digital-to-analog converter), and FPGA (field-programmable gate array) as a real-time signal acquisition and processing platform, employing advanced modulation, demodulation, and encoding / decoding algorithms to achieve high-bitrate signal processing. It employs a modular design with independent internal transmit and receive channels. The system platform utilizes a highly optimized topology, providing users with interconnectivity across various high-speed serial buses. It utilizes horizontal plug-in cards, and all boards have heat sinks for heat dissipation.

[0087] 2. Measurement and control baseband equipment

[0088] The measurement and control baseband equipment completes the encoding / modulation of remote control data, the demodulation / decoding / synchronization of telemetry signals, and has dual-channel single pulse tracking capability.

[0089] The measurement and control baseband equipment primarily consists of a chassis, CPU board, digital baseband module, up / down converters (intermediate frequency band), tracking module, and supporting accessories. Its CPCI bus architecture supports the expansion of subsequent baseband modules, and it features universal chassis integrated control, power supply, fan, and data exchange functions, making it scalable.

[0090] 4. Time-Frequency Division System

[0091] The time-frequency subsystem provides a 10MHz reference source and unified time reference information, and distributes it according to the needs of various devices at the gateway station.

[0092] The time and frequency division system includes GNSS satellite receiving antennas and positioning, orientation and timing equipment.

[0093] 1. GNSS satellite receiving antenna

[0094] The GNSS satellite receiving antenna can accurately receive GNSS satellite signals and has good anti-interference performance.

[0095] 2. Positioning, orientation and timing equipment

[0096] The positioning, direction-setting and timing equipment locks and disciplines the high-stability crystal oscillator inside the machine to achieve complete synchronization between the local clock and the satellite clock received by the receiver.

[0097] The positioning, orientation, and timing equipment of the present invention is preferably a Beidou synchronized clock device. This device primarily consists of a receiver module, a base station differential information input module, a main control module, a key / display module, a phase lock module, a positioning and orientation data output module, a 10MHz frequency standard output module, a 1PPS output module, a B-code output module, an NTP / PTP monitoring output module, and a power supply module. It supports multiple differential modes and can meet various positioning accuracy requirements, ranging from meter-level, centimeter-level, to millimeter-level. It also supports heading information output and provides attitude information such as pitch and roll to assist in positioning and orientation reacquisition.

[0098] 5. In-site network management subsystem

[0099] The network management subsystem in the station monitors and controls all equipment in the gateway station, connecting all monitored equipment through Ethernet switches and terminal servers.

[0100] The in-site network management subsystem includes application software and hardware equipment.

[0101] 1. Application software

[0102] The application software, deployed on the site's servers using a B / S architecture, serves as the core system for terminals to display site topology, monitor device status, and issue device control commands. Site users can access the software directly through a browser on their LAN terminals. Remote users can also access the software directly through a browser after connecting to the site via VPN or other means. The overall software architecture consists of three layers: the foundational support layer, the service layer, and the presentation layer.

[0103] 2. Hardware

[0104] The hardware primarily consists of servers and displays. The server provides an installation platform for system software deployment and possesses significant computing and storage capabilities. The display provides the operator with a visual representation of the human-machine interface, along with device status data and alarm information.

[0105] VI. Security Subsystem

[0106] The security subsystem provides safe and reliable environmental conditions to ensure the normal operation and daily inspection and maintenance of various equipment in the gateway station.

[0107] The security subsystem includes security and control equipment, switching and transmission equipment, environmental control and protection equipment, and inspection doors.

[0108] 1. Security and control equipment

[0109] Security control equipment provides basic monitoring and security protection capabilities.

[0110] The security and control equipment mainly consists of network cameras, RF lightning arresters and signal lightning arresters.

[0111] like Figure 1 As shown, the network camera 12 is mounted on the antenna chassis 6, and the device can see a clearer picture through zoom. The camera has a built-in pan / tilt, which can be controlled by the background to achieve 360° rotation to observe the operating status of the antenna.

[0112] RF lightning arresters are installed on the RF transmission lines of wireless communication equipment. When the antenna feed network is subjected to lightning overvoltage and various electronic interferences, the lightning current and interference waves are discharged to the ground through the lightning arrester.

[0113] The signal lightning arrester is installed at the front end of the port of the protected signal equipment. When the transmission signal line is subjected to overvoltage or overcurrent caused by static electricity or lightning induction, the signal lightning arrester quickly discharges the lightning to the ground and limits the overvoltage and overcurrent to the range allowed by the equipment, ensuring the safe operation of the equipment.

[0114] 2. Switching and transmission equipment

[0115] Switching and transmission equipment provides data exchange and data transmission capabilities.

[0116] Switching and transmission equipment mainly consists of optical fibers and switches.

[0117] Optical fiber: Optical transmission technology offers advantages such as ease of use and immunity to electromagnetic interference and lightning. Its excellent shielding, tensile strength, and adaptability to temperatures as low as -40°C (-140°F) enable long-distance transmission of optical signals with low loss.

[0118] Switches: Forward data to their destinations through packet switching and support network connectivity among multiple devices. The control center can remotely access and control each device through switches.

[0119] 3. Environmental control and protection equipment

[0120] Environmental control and protection equipment provides good protection conditions and temperature and humidity environment.

[0121] Environmental control and protection equipment mainly consists of lighting equipment, temperature and humidity sensors, heaters, air conditioners (refrigeration) and antenna covers.

[0122] like Figure 1As shown, the lighting device 11 is installed on the antenna chassis 6. It consists of a lamp holder and a lamp, and an energy-saving lamp is selected for installation to provide lighting for the interior of the antenna cover 8.

[0123] The temperature and humidity sensor 13 is mounted on the antenna chassis 6. Using an integrated temperature and humidity probe as the temperature measuring element, it collects temperature and humidity signals. After processing through circuits such as voltage stabilization and filtering, operational amplification, nonlinear correction, V / I conversion, constant current, and direction protection, it is converted into a current or voltage signal that is linearly related to temperature and humidity. It can also be directly output through an RS485 or RS422 interface through the main control chip.

[0124] Heater 10 is mounted on antenna chassis 6. A target temperature can be set as desired. When the ambient temperature reaches the set value, the thermostat automatically shuts off the power supply and stops heating. Once the temperature drops, the thermostat reconnects to resume heating, maintaining a stable ambient temperature. Even when the ambient temperature is low, heater 10 ensures a suitable ambient temperature for the various devices within antenna cover 8.

[0125] The air conditioning (refrigeration) system consists of an indoor unit 15 and an outdoor unit 14. The indoor unit 15 is mounted above the antenna chassis 6, while the outdoor unit 14 is mounted below the antenna chassis 6. This system primarily reduces the temperature inside the antenna cover 8 in high-temperature environments, ensuring a favorable ambient temperature for the operation of various devices within the antenna cover 8.

[0126] The radome 8 is mounted on the antenna chassis 6. It utilizes an A-type modified foam / modified honeycomb sandwich structure, with the skin material being FEVE membrane. This membrane exhibits excellent electrical properties, high strength, and excellent hydrophobicity, preventing dust contamination. It is also highly resistant and durable to sunlight, chemical solvents, acid and alkali corrosion, moisture, and oxidation, and can withstand wind speeds of 67 m / s. This radome 8 encloses the antenna and other mounted equipment, ensuring that the antenna and other equipment on the chassis can operate around the clock in harsh environments such as wind, rain, ice, and snow. The radome 8 includes a single-person access door 9, allowing maintenance personnel to enter the radome 8 and perform routine maintenance and inspections.

[0127] 4. Inspection door

[0128] like Figure 1 As shown, it is convenient for maintenance personnel to enter the antenna cover 8 through the maintenance door 9 to perform daily maintenance and repair of the equipment.

[0129] The working process of the low-orbit satellite micro-gateway system of the present invention is as follows:

[0130] S1, site planning, investigation and construction.

[0131] S2, assign work tasks to the gateway system according to the instructions of superiors.

[0132] S3: The gateway station antenna is guided by a program to point to a specific target satellite (low-orbit satellite).

[0133] S4, the time and frequency terminal provides a 10MHz frequency source and a unified time reference for each gateway device, ensuring that each gateway device provides a safe and reliable working environment for the gateway system.

[0134] S5, low-orbit satellite passes by, and the payload feed beam covers the gateway area.

[0135] S6, the gateway antenna receives low-orbit satellite signals, amplifies and down-converts the signals, and outputs two signals, one to the feed baseband and the other to the measurement and control baseband.

[0136] S7: After baseband processing, the data enters the ground bearer network through optical fiber.

[0137] S8, after the measurement and control baseband processing, the telemetry data is output to complete the on-line measurement and control, and the tracking data is fed back to the regional control unit.

[0138] S9, the regional control unit realizes single-pulse self-tracking of a specific target satellite based on the antenna azimuth and pitch error angle information fed back by the measurement and control baseband.

[0139] S10, the uplink signal passes through the feeding / measurement and control baseband equipment → BUC equipment → gateway station antenna in sequence, realizing the transmission of uplink communication signals and remote control signals.

[0140] S11, repeat S3 to S10 until the gateway system sends a stop or standby command.

[0141] The contents not described in detail in the specification of the present invention belong to the existing public technologies in this technical field.

Claims

1. A low-orbit satellite micro-gateway system, characterized in that: It includes antenna servo feed subsystem, radio frequency subsystem, baseband subsystem, time and frequency subsystem, in-station network management subsystem and support subsystem; The servo-feedback system realizes the capture and tracking of specific target satellites in the entire airspace, as well as the uplink transmission and downlink reception of signals; The radio frequency subsystem realizes up-conversion and power amplification of uplink signals, signal amplification and down-conversion of downlink signals, and down-conversion of uplink calibration signals; The baseband subsystem realizes synchronization, demodulation, decoding of downlink feed signals and encoding and modulation of uplink feed signals; The time-frequency subsystem provides a 10MHz reference source and unified time reference information, and distributes it according to the needs of each device in the gateway station; The in-station network management subsystem monitors and controls all devices at the gateway station, connecting all monitored devices via Ethernet switches and terminal servers; The security subsystem provides a safe and reliable environment to ensure the normal operation and routine inspection and maintenance of all equipment in the gateway station.

2. The low-orbit satellite micro-gateway system according to claim 1, characterized in that: The antenna servo feed subsystem includes an antenna feed subsystem, a mechanical structure subsystem, a servo control subsystem and a tracking subsystem; The antenna subsystem provides a radio frequency channel, generates the sum and difference signals required for self-tracking, and completes the reception and transmission of microwave signals; The mechanical structure subsystem achieves miniaturization of the gateway antenna structure by adjusting the antenna focal diameter ratio, changing the antenna mount form, and rationally arranging the installation position of the gateway equipment; The servo control subsystem completes the drive control and maintenance of the gateway antenna, and realizes the pointing and capture of the specific target satellite; The tracking subsystem completes the amplification and down-conversion of the difference path signal, and provides the antenna azimuth, pitch error voltage, AGC value and lock indication to the regional control unit through the tracking receiver, thereby realizing the self-tracking of the gateway station antenna.

3. The low-orbit satellite micro-gateway system according to claim 1, characterized in that: The RF subsystem includes a BUC device, an LNB device and a calibration downconverter; the BUC device up-converts the intermediate frequency signal from the baseband and outputs it at high power; the LNB device amplifies and down-converts the RF signal received by the gateway antenna and outputs it; the calibration downconverter converts the uplink frequency to the downlink frequency.

4. The low-orbit satellite micro-gateway system according to claim 1, characterized in that: The baseband subsystem includes a feed baseband device and a measurement and control baseband device; the feed baseband device completes the encoding / modulation and demodulation / decoding / synchronization of the feed data to achieve high code rate signal processing; The measurement and control baseband equipment completes the encoding / modulation of remote control data, the demodulation / decoding / synchronization of telemetry signals, and has a dual-channel single pulse tracking capability.

5. The low-orbit satellite micro-gateway system according to claim 1, characterized in that: The time-frequency division system includes a GNSS satellite receiving antenna and a positioning, orientation and timing device; the GNSS satellite receiving antenna accurately receives GNSS satellite signals and has good anti-interference performance; The positioning, orientation and timing device locks and disciplines the high-stability crystal oscillator inside the device to achieve complete synchronization between the local clock and the satellite clock received by the receiver.

6. The low-orbit satellite micro-gateway system according to claim 1, characterized in that: The in-site network management subsystem includes application software and hardware equipment; the application software is deployed on the in-site server using a B / S architecture to realize site topology display, equipment status monitoring and equipment control instruction issuance; the hardware equipment provides an installation platform for the deployment of various system software and has computing and storage capabilities.

7. The low-orbit satellite micro-gateway system according to claim 1, characterized in that: The security subsystem includes security control equipment, switching and transmission equipment, environmental control and protection equipment and an inspection door; the security control equipment provides basic monitoring and safety protection capabilities; the switching and transmission equipment provides data exchange and data transmission capabilities; the environmental control and protection equipment provides protection conditions and temperature and humidity environment; the inspection door facilitates maintenance personnel to enter the antenna cover through the inspection door to perform daily maintenance and inspection of the gateway equipment.

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