An X-band portable integrated satellite ground station

Abstract

The present invention provides an X-band portable integrated satellite ground station, which relates to the field of satellite measurement, control, and communication technology, and includes an antenna feed device, an X-band BUC device, a downlink receiving channel device, a portable baseband, and a station monitoring device. The parabolic antenna in the antenna feed device uses eight assembled carbon fiber panels, and the central column is equipped with a power supply, a timing and positioning module, a servo control device, and other equipment. The tripod is retractable and detachable. The X-band BUC device and the downlink receiving channel device both adopt an integrated design. The portable baseband has measurement and control and low-speed data transmission functions, and the entire device is designed as an outdoor model, making it more portable and lightweight. The station monitoring device has strong automated operation capabilities and can execute tasks with one click. Therefore, the X-band portable integrated satellite ground station has the characteristics of low cost, multi-functional integrated design, small size, light weight, and simplicity and ease of use. It is suitable for a variety of application scenarios such as emergency measurement and control, low-speed remote sensing reception, and high-speed satellite injection.

Description

Technical Field

[0001] The present invention relates to the technical field of satellite measurement, control and communication, and in particular to an X-band portable integrated satellite ground station. Background Art

[0002] With the rapid development of remote sensing technology, it has been widely used in a variety of fields, including environmental monitoring, agriculture, urban planning and management, natural resource management, meteorological observation, and disaster prevention and mitigation. The development of domestic commercial remote sensing satellites has entered a new stage, with a user base shifting from primarily government to a balanced mix of government, businesses, and the general public. The scale of these satellites continues to expand, with numerous state-owned and private enterprises launching plans for commercial remote sensing satellite constellations. Satellite ground stations are an integral part of remote sensing satellite communication systems, responsible for two-way communication with satellites and ensuring their normal operation, information reception, and processing.

[0003] Satellite ground stations are an integral part of low- and medium-orbit satellite communication systems. They are responsible for two-way communication with satellites, ensuring their proper operation, and for receiving and processing information. Satellite ground stations not only play a vital role in communications but also have extensive applications in remote sensing, meteorological observation, ocean monitoring, and other fields. For example, satellite remote sensing technology enables land resource monitoring, meteorological disaster warnings, and marine environmental monitoring, providing crucial data support for scientific research, resource management, environmental protection, and disaster prevention.

[0004] Existing fixed satellite ground stations can only carry out measurement, control and communication tasks for transit satellites in designated areas. They cannot be moved and have no mobility. At the same time, the fixed stations have a large amount of equipment. For example, frequency converters are divided into telemetry downconverters, data transmission downconverters, and remote control upconverters according to their functions. Portable basebands are divided into measurement and control portable basebands and data transmission portable basebands according to their functions. In addition, there are many link backups and the operation is relatively complicated. Traditional portable satellite ground stations (referred to as portable stations) adopt a decentralized design for various functional equipment and lack a system integration design. Each device is connected by cables to realize the system function of the portable station. The installation and disassembly of the equipment takes a lot of time. At the same time, the portable station is large in size and heavy in overall weight. Therefore, there is an urgent need to develop a set of low-cost, multi-functional integrated integrated design, small and light, and highly maneuverable and flexible integrated satellite ground stations. Summary of the Invention

[0005] The purpose of the present invention is to provide an X-band portable integrated satellite ground station, which has the characteristics of low cost, multi-functional integrated design, small size, light weight and ease of use. It can be applied to various application scenarios such as emergency measurement and control, low-speed remote sensing reception, and high-speed satellite injection.

[0006] The embodiments of the present invention are achieved through the following technical solutions:

[0007] An X-band portable integrated satellite ground station, comprising antenna feed equipment, X-band BUC equipment, downlink receiving channel equipment, portable baseband and station monitoring equipment;

[0008] The uplink RF input terminal of the antenna feed device is connected to the output terminal of the X-band BUC device, and the downlink RF output terminal of the antenna feed device is connected to the RF input terminal of the downlink receiving channel device;

[0009] The intermediate frequency input terminal of the X-band BUC device is connected to the intermediate frequency output terminal of the portable baseband, and the power amplifier coupling output terminal of the X-band BUC device is connected to the test input terminal of the downlink receiving channel;

[0010] The intermediate frequency output terminal of the downlink receiving channel device is connected to the portable baseband input terminal, and the downlink receiving channel device converts the power amplifier coupling signal sent by the X-band BUC device into a downlink radio frequency test signal and amplifies it.

[0011] Furthermore, the antenna servo feed device includes an antenna feed component, a servo control component, an antenna bracket, a positioning and timing module, and a power supply module. The antenna feed component includes a parabolic antenna and an X-band feed source. The X-band feed source is used to receive signals from medium and low-orbit remote sensing satellites and transmit the satellite signals to the downlink receiving channel device, as well as transmit the remote control commands sent by the X-band BUC device to the satellite through the parabolic antenna.

[0012] The servo control component is used to monitor and control the attitude of the parabolic antenna;

[0013] The top of the column of the antenna bracket is used to install the parabolic antenna, the inside of the column of the antenna bracket is used to install the power module, the timing and positioning module and the servo control board, and the bottom of the column is used to install the support legs;

[0014] The positioning and timing module can provide positioning, orientation and timing signals for station monitoring equipment.

[0015] Furthermore, the reflecting surface of the parabolic antenna adopts an 8-petal assembly structure, and each reflecting surface is connected by a positioning pin and a locking mechanism.

[0016] Furthermore, the parabolic antenna mount adopts an XY type.

[0017] Furthermore, the reflective surface is made of a carbon fiber panel.

[0018] Furthermore, the antenna bracket is a tripod.

[0019] Furthermore, the X-band BUC device includes a DC power supply unit, an up-conversion module, a power amplifier module, and a monitoring unit, wherein the DC power supply unit is used to supply power to the up-conversion module, the power amplifier module, and the monitoring unit;

[0020] The up-conversion module is used to up-convert the uplink intermediate frequency signal transmitted by the portable baseband;

[0021] The power amplifier module is used to amplify the power of the uplink radio frequency after up-conversion and send the amplified radio frequency signal to the antenna feed device;

[0022] The monitoring unit is used to monitor and control the DC power supply unit, the up-conversion module and the power amplifier module.

[0023] Furthermore, the up-conversion module adopts a secondary frequency conversion method.

[0024] Furthermore, the downlink receiving channel device includes an X-band LNA1, an X-band LNA2, and an X-band high-frequency box, wherein the signal input ends of the X-band LNA1 and the X-band LNA2 are both communicatively connected to the antenna feed device, and the signal output ends of the X-band LNA1 and the X-band LNA2 are both communicatively connected to the X-band high-frequency box;

[0025] The X-band high frequency box is used to select and frequency convert the radio frequency signals output by the X-band LNA1 and the X-band LNA2, and frequency convert the power amplifier coupled signal output by the X-band BUC device, and send it to the downlink channel for self-test.

[0026] Furthermore, the X-band high frequency box includes a monitoring module, a calibration and self-test module, a radio frequency switch, an X-band telemetry down-conversion module, an X-band data transmission down-conversion module, a frequency synthesis module and a DC-DC power supply.

[0027] The monitoring module is used to monitor and control the working status of the radio frequency switch, the X-band telemetry down-conversion module, the X-band data transmission down-conversion module and the calibration and self-test module according to the parameters output by the station monitoring equipment;

[0028] The frequency synthesis module is used to send corresponding local oscillator signals to the X-band telemetry down-conversion module, the X-band data transmission down-conversion module and the calibration and self-test module according to the operating frequency sent by the monitoring module;

[0029] The calibration and self-test module is used to down-convert the power amplifier coupling signal output by the X-band BUC device according to the control instructions sent by the monitoring module and the corresponding local oscillator signal, and output the converted test signal to the X-band LNA1 and X-band LNA2 respectively;

[0030] The RF switch is used to select and output the input RF signal to the X-band telemetry down-conversion module and the X-band data transmission down-conversion module according to the control instruction sent by the monitoring module;

[0031] The X-band telemetry down-conversion module and the X-band data transmission down-conversion module are used to perform frequency conversion and amplification processing on the local oscillator signal according to the working parameters sent by the monitoring module, generate corresponding measurement and control and data transmission signals and output them to the portable baseband;

[0032] The DC-DC power supply is used to power the frequency synthesis module, the radio frequency switch, the X-band telemetry down-conversion module, the X-band data transmission down-conversion module, the calibration and self-test module, and the monitoring module.

[0033] The technical solutions of the embodiments of the present invention have at least the following advantages and beneficial effects:

[0034] The present invention discloses an X-band portable integrated satellite ground station. By adopting an integrated design, the volume of each device can be effectively reduced, thereby making the local ground station portable and enabling more flexible measurement, control and communication with transiting satellites. In addition, the portability of the local ground station is greatly improved by adopting an 8-petal parabolic antenna structure and a foldable tripod antenna bracket.

[0035] The downlink receiving channel adopts an integrated design, integrating the calibration and self-test module, X-band telemetry down-conversion module, X-band data transmission down-conversion module, and RF switch into a single box. The size of the entire high-frequency box is 190mm×160mm×58.2mm (including the height of the heat dissipation teeth). The high-frequency box is installed between the antenna feed and the antenna Y-axis turntable. It adopts an outdoor design. Compared with traditional fixed station channel equipment, it has the characteristics of small integration, rainproof and low power consumption, making the entire portable station more concise while meeting performance requirements, thereby improving the portability of the system.

[0036] The portable baseband adopts software radio technology and realizes simultaneous or time-sharing non-coherent spread spectrum telemetry and remote control functions and data transmission portable baseband functions through dynamic loading. The portable baseband adopts an outdoor design, and the size of the portable baseband is 24mm×229mm×87mm (including the height of the heat dissipation teeth). The existing measurement and control station portable basebands are divided into measurement and control portable basebands and data transmission portable basebands according to their functions. At the same time, most of them are designed as indoor types, with a size of 2U or 4U height 19-inch plug-in box. This portable baseband adopts an integrated design of measurement and control and data transmission. The whole structure has the characteristics of windproof, rainproof and high temperature resistance. The whole machine is powerful and integrates measurement and control and data transmission functions, but the price is much lower than that of traditional portable basebands.

[0037] In addition, the software in the station monitoring device 5 automatically generates a task flow according to the equipment work plan sent by the center, and organizes all the equipment in the station to sequentially execute the various processes in the task flow, without the need to set the parameters of each device separately, and automatically completes the specified tasks; at the same time, the station monitoring software dynamically displays the satellite flight orbit plan, transit time, mission forecast and received signal spectrum diagram in real time, etc. Compared with traditional ground measurement and control station monitoring software, it is more intelligent and easier to operate. At the same time, it uses a three-dimensional graphic form to more intuitively display the satellite status and the quality of the received signal, realizing automatic operation.

[0038] In addition, the antenna feed device 1 adopts a program to track the target satellite. In order to ensure the pointing accuracy requirements, angle calibration is required before the satellite tracking mission begins. Traditional angle calibration methods include the calibration tower method (which requires an optical telescope and geodetic measurement) and the radio star method (using a radio star with a known precise position as a reference source). Considering the actual use scenarios of the portable ground station, such as working in Gobi, uninhabited areas and coastal areas, or in emergency rescue, temporary tasks and other use scenarios, and considering the construction cost, the above angle calibration method cannot meet the use requirements of the portable station. Therefore, the present invention also relates to a fast and automatic angle calibration method;

[0039] The workflow for rapid automatic angle calibration is as follows: First, the positioning and timing module provides an initial angle reference, controlling the antenna angle error to within 0.1°. Then, under program-guided operation, the antenna performs a secondary correction to the real-time antenna angle by superimposing azimuth / elevation offsets and comparing the AGC voltage (this process runs automatically in the background), controlling the pointing accuracy error to within 0.05°. Finally, based on the fine orbit data sent by the central station control and the antenna's own error voltage, the local measurement system angle data is automatically and accurately corrected in real time (this process can be performed remotely and calibrated afterwards), controlling the pointing accuracy error to an accuracy equivalent to the provided orbit data. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0041] Figure 1 A schematic diagram of the structure provided in Example 1 of the present invention;

[0042] Figure 2 This is a schematic structural diagram of an X-band high-frequency box provided in Example 4 of the present invention.

[0043] Icons: 1. Antenna feed equipment; 2. X-band BUC equipment; 211. Monitoring module; 212. Calibration and self-test module; 213. RF switch; 214. X-band telemetry down-conversion module; 215. X-band data transmission down-conversion module; 216. Frequency synthesizer module; 217. DC-DC power supply; 3. Downlink receiving channel equipment; 4. Portable baseband; 5. Station monitoring equipment. DETAILED DESCRIPTION

[0044] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0045] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort shall fall within the scope of protection of the present invention.

[0046] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0047] In the description of the present invention, it should be noted that if the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the accompanying drawings, or is the orientation or position relationship in which the product of the application is usually placed when in use. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0048] It should also be noted that, in the description of the present invention, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention in specific contexts.

[0049] Example 1

[0050] As attached Figure 1 The illustrated embodiment shows an X-band portable integrated satellite ground station, comprising an antenna feed device 1, an X-band BUC device 2, a downlink receiving channel device 3, a portable baseband 4, and a station monitoring device 5;

[0051] The signal receiving end of the antenna feed device 1 is communicatively connected to the X-band BUC device 2, and the signal transmitting end of the antenna feed device 1 is communicatively connected to the downlink receiving channel device 3;

[0052] The main function of the antenna feed device 1 is to complete the reception of signals from medium and low orbit remote sensing satellites and send uplink remote control commands;

[0053] The signal receiving end of the X-band BUC device 2 is communicatively connected to the portable baseband 4, and the signal transmitting end of the X-band BUC device 2 is communicatively connected to the downlink receiving channel device 3;

[0054] The X-band BUC device 2 mainly up-converts the intermediate frequency signal output by the portable baseband 4 and performs power amplification;

[0055] The intermediate frequency output terminal of the downlink receiving channel device 3 is connected to the input terminal of the portable baseband 4, and the downlink receiving channel device 3 converts the power amplifier coupling signal sent by the X-band BUC device 2 into a downlink RF test signal, and then sends it to the X-band LNA for amplification;

[0056] The station monitoring device 5 exchanges information with the antenna feed device 1, the X-band BUC device 2, the downlink receiving channel device 3 and the portable baseband 4 respectively;

[0057] It should be noted that the portable baseband 4 adopts software radio technology, and realizes simultaneous or time-sharing non-coherent spread spectrum telemetry and remote control functions and data transmission portable baseband 4 functions through dynamic loading. The portable baseband 4 adopts an outdoor design, and the size of the portable baseband 4 is 24mm×29mm×87mm (including the height of the heat dissipation teeth). The existing measurement and control station portable baseband 4 is divided into measurement and control portable baseband 4 and data transmission portable baseband 4 according to function. At the same time, most of them are designed as indoor types, with a size of 2U or 4U height 19-inch plug-in box. This portable baseband 4 adopts an integrated design of measurement and control and data transmission. The structure of the whole machine has the characteristics of windproof, rainproof and high temperature resistance. The whole machine is powerful and integrates measurement and control and data transmission functions, but the price is much lower than the traditional portable baseband 4.

[0058] The workflow of this integrated ground station is as follows:

[0059] 1) The station monitoring device 5 resolves conflicts and forms a station work plan based on the mission plan or satellite ephemeris data of the operation control center;

[0060] 2) Before the satellite passes, the station monitoring device 5 sends antenna guidance data to the antenna feed device 1. The antenna feed device 1 controls the antenna to the designated position and waits. The station monitoring device 5 sends operating parameter control instructions to the X-band BUC device 2, the downlink receiving channel device 3, and the portable baseband 4.

[0061] 3) When the satellite passes by, the antenna feed device 1 uses a program tracking method to point to the target and receive the downlink telemetry or data transmission signal; the downlink receiving channel 3 receives the downlink RF signal received by the antenna feed device 1, selects the left and right rotation signals according to the frequency information and rotation information sent by the station monitoring device 5, and sends them to the X-band telemetry down-conversion module 214 or the X-band data transmission down-conversion module 215, which frequency-converts the RF signal to an intermediate frequency 70MHz telemetry signal or a 1200MHz data transmission signal, and sends the output intermediate frequency signal to the portable baseband 4; the portable baseband 4 selects the left and right rotation signals according to the frequency information and rotation information sent by the station monitoring device 5, and sends them to the X-band telemetry down-conversion module 214 or the X-band data transmission down-conversion module 215, which converts the RF signal to an intermediate frequency 70MHz telemetry signal or a 1200MHz data transmission signal, and sends the output intermediate frequency signal to the portable baseband 4; the portable baseband 4 selects the left and right rotation signals according to the frequency information and rotation information sent by the station monitoring device 5, and sends the selected left and right rotation signals to the X-band telemetry down-conversion module 214 or the X-band data transmission down-conversion module 215. The control device 5 issues telemetry tasks or data transmission tasks, dynamically loads the measurement and control mode or data transmission mode program, performs signal demodulation, decoding, bit synchronization, frame synchronization, descrambling, and other processing, and stores the telemetry data or data transmission data locally or forwards it to the operation and control center. For example, if the station monitoring device 5 issues a remote control command to the portable baseband 4, the portable baseband 4 must complete channel coding as required and send the debugged intermediate frequency signal to the X-band BUC device 2. The X-band BUC device 2 converts the intermediate frequency signal to the X-band, then amplifies the signal and sends it to the antenna feed device 1 for transmission to the satellite.

[0062] 4) The station monitoring equipment 5 monitors the parameters and status of each device in real time, generates a work report after the task is completed and reports it to the operation control center.

[0063] Example 2

[0064] Furthermore, the antenna feed device 1 includes an antenna feed component, a servo control component, an antenna bracket, a positioning and timing module, and a power supply module.

[0065] The antenna and feed assembly includes a 1.2-meter parabolic antenna and an X-band feed source. The 1.2-meter parabolic antenna adopts a ring-focus antenna. In order to improve the antenna efficiency and reduce the antenna sidelobes, the main and sub-reflectors of the antenna are shaped and optimized. The main geometric parameters of the antenna after shaping optimization are selected as follows: main reflector diameter: 1200mm, sub-reflector diameter: 150mm; main surface accuracy: better than 0.5mm (RMS); sub-surface accuracy: better than 0.10mm (RMS). The X-band feed source adopts a card feed form, which consists of an X-band horn, a corrugated polarizer, an orthogonalizer, and a transceiver duplexer. It is mainly used to receive signals from medium and low-orbit satellites and transmit remote control commands to satellites.

[0066] The parabolic antenna adopts a ring-focus antenna. In order to improve the antenna efficiency and reduce the antenna sidelobes, the main and sub-reflecting surfaces of the antenna are shaped and optimized. Specifically, the reflecting surface of the parabolic antenna adopts an 8-petal assembly structure, and each reflecting surface is connected by a positioning pin and a locking mechanism. At the same time, in order to reduce weight, the reflecting surface adopts a carbon fiber panel. The weight of each petal reflecting surface is ≤1.25kg, and the total weight of the reflecting surface is ≤10.0kg. Compared with the traditional parabolic antenna reflecting surface, it is lighter and the reflecting surface can be disassembled and carried for easy carrying. The main geometric parameters of the antenna after shaping optimization are selected as follows: main reflector diameter: 1200mm, sub-reflector diameter: 150mm; main surface accuracy: better than 0.5mm (RMS); sub-surface accuracy: better than 0.10mm (RMS);

[0067] In addition, the parabolic antenna mount adopts an XY type, which has significant advantages over traditional AE or AET antenna mounts in terms of antenna weight, volume, servo system complexity, power consumption, transportation and installation difficulty, site layout flexibility, and cost. To reduce the space occupied by system equipment, the antenna servo control ACU and antenna drive ADU are integrated into the mount, and the overall weight of the antenna mount is ≤21kg.

[0068] The X-band feed adopts a card feed form, consisting of an X-band horn, a corrugated polarizer, an orthogonalizer, and a transceiver duplexer. It is mainly used to receive signals from medium and low-orbit satellites and transmit remote control commands to satellites. In addition, the antenna feed meets the following indicators: operating frequency: X-band reception: 7.7GHz~9.0GHz; X-band transmission: 7.145GHz~7.25GHz; antenna gain: ≥38.2+20×log(f / 8350MHz)dBi; ≥36.3+20×log(f / 7200MHz)dBi; planning mode: transmission: left-hand circular polarization and right-hand circular polarization time-sharing; reception: left-hand circular polarization and right-hand circular polarization simultaneously; antenna noise temperature: X-band: ≤90K; first sidelobe: ≤-12dB; transmit and receive isolation: 85dB;

[0069] The servo control unit is mainly used to monitor and control the 1.2-meter antenna equipment. In the program tracking mode, the servo control unit drives the antenna's X-axis and Y-axis rotation to control the antenna's posture, thereby achieving precise pointing and tracking of the antenna's electrical axis;

[0070] In addition, the indicators achieved by the servo unit include: tracking accuracy: better than 1 / 7 half-power beam width; pointing accuracy: better than 1 / 5 half-power beam width; program tracking capability: capture at elevation angles greater than 3°, stable tracking at elevation angles greater than 5°, and no loss of target when the program passes over the top

[0071] The top of the column of the antenna bracket is used to install the parabolic antenna, the inside of the column of the antenna bracket is used to install the power module, the timing and positioning module and the servo control board, and the bottom of the column is used to install the support legs;

[0072] In addition, the antenna bracket adopts a tripod, and the bracket has the function of being foldable and easy to carry. The power module, timing and positioning module and servo control board are placed in the antenna pillar, and the pillar and the tripod legs are connected by positioning pins and screws. The tripod legs are all retractable structures, which is conducive to reducing the size of the transportation unit. The overall weight is ≤13kg; the X-band BUC equipment 2 and the X-band high-frequency box are installed between the antenna feed and the antenna Y-axis turntable, and do not need to be disassembled and assembled separately. They are integrated above the antenna mount, and the channel weight is ≤6kg. Compared with traditional ground station channel equipment, it has the advantages of high integration, light weight and low power consumption; the portable baseband 4 of this integrated ground station weighs ≤5kg, and the weight of the entire system is ≤55kg. Compared with traditional ground stations, this portable station is not restricted by the site, and two people can quickly install and remove the equipment. It has strong mobility, is easy to carry, and has low cost.

[0073] The power module mainly converts the external AC 20V into a 24V DC power supply to provide power for all devices in the portable station, including the antenna feed device 1, the X-band BUC device 2, the downlink receiving channel device 3, the portable baseband 4 and the station monitoring device 5.

[0074] The positioning and timing module is capable of providing positioning, orientation and timing signals to the station monitoring device 5;

[0075] The technical indicators achieved by the positioning and timing module include: automatic north-seeking accuracy: better than 0.2° (1-meter baseline); automatic positioning accuracy: better than 10m; timing accuracy: ≤20ns; output 10MHz frequency indicators: accuracy:, stability:; number of output channels: 3; output B code type: I RI GB (DC) code; time code demodulation synchronization error: ≤400ns; number of B code output channels: 2.

[0076] Example 3

[0077] Furthermore, the X-band BUC device 2 includes a DC power supply unit, an up-conversion module, a power amplifier module, and a monitoring unit, wherein the DC power supply unit is used to supply power to the up-conversion module, the power amplifier module, and the monitoring unit;

[0078] The up-conversion module is used to up-convert the uplink intermediate frequency signal transmitted by the portable baseband 4;

[0079] The power amplifier module is used to amplify the power of the uplink radio frequency after up-conversion and send the amplified radio frequency signal to the antenna feed device 1;

[0080] The monitoring unit is used to monitor and control the DC power supply unit, the up-conversion module and the power amplifier module;

[0081] The X-band upconversion module uses secondary frequency conversion. The 70MHz signal is mixed up to 650MHz through a 580MHz local oscillator, and then mixed with the second local oscillator of 6495MHz to 6600MHz generated by the frequency synthesizer to produce the uplink RF signal. Its frequency range is 7145MHz to 7250MHz, and the signal frequency step is 1kHz. The technical indicators achieved by X-band BUC device 2 include: input intermediate frequency: 70MHz±10MHz, in 1kHz steps; input signal level adaptable range: -10dBm±5dB; input reference signal: 10MHz; output operating frequency: 7145MHz~7250MHz; output power: P-1≥50W, adjustable by 20dB in 1dB steps; power stability: ±0.5dB / 24h (constant excitation); clutter suppression: ≥60dB; second harmonic: ≤-50dBc; group delay: in-band group delay variation ≤10ns, 24h absolute delay variation ≤10ns.

[0082] Example 4

[0083] Furthermore, the downlink receiving channel device 3 includes an X-band LNA1, an X-band LNA2, and an X-band high-frequency box, wherein the signal input ends of the X-band LNA1 and the X-band LNA2 are both communicatively connected to the antenna feed device 1, and the signal output ends of the X-band LNA1 and the X-band LNA2 are both communicatively connected to the X-band high-frequency box;

[0084] X-band LNA1 and X-band LNA2 filter and amplify the downlink RF signal received by antenna feed device 1 before sending it to the X-band high-frequency box for down-conversion. Technical specifications achieved by the X-band LNA include: operating frequency: 7.7 GHz to 9.0 GHz; noise temperature: ≤60K; gain: ≥50 dB; output 1 dB compression point: ≥+10 dBm; in-band ripple: ≤±0.6 dB.

[0085] The X-band high frequency box is used to select and frequency-convert the RF signals output by the X-band LNA1 and X-band LNA2. It also has the function of frequency-converting the power amplifier coupled signal output by the X-band BUC device 2 and sending it to the downlink channel for self-testing.

[0086] The X-band high-frequency box meets the following technical specifications: Input operating frequency: 2 channels from 7.7GHz to 9.0GHz, 1 channel from 7.145GHz to 7.25GHz; Input reference signal: 10MHz; Output frequency: 1 channel from 70MHz, 1 channel from 1200MHz, 2 channels from 7.7GHz to 9.0GHz; 1dB output compression point: ≥+10dBm; In-band flatness: ±0.4dB (within ±10MHz), ≤±1dB (within ±200MHz); Out-of-band suppression: ≥50dB; Spurious: ≤-50dBc; Local oscillator phase noise: ≤-60dBc / Hz at 10Hz, ≤-75dBc / Hz at 100Hz, ≤-85dBc / Hz at 1kHz, ≤-95dBc / Hz at 10kHz, ≤-105dBc / Hz at 100kHz.

[0087] It should be noted that the X-band high-frequency box adopts an integrated design, integrating the calibration and self-test module 212, the X-band telemetry down-conversion module 214, the X-band data transmission down-conversion module 215, and the RF switch 213 into one box. The size of the entire high-frequency box is 190mm×160mm×58.2mm (including the height of the heat dissipation teeth). The high-frequency box is installed between the antenna feed and the antenna Y-axis turntable. It adopts an outdoor design. Compared with traditional fixed station channel equipment, it has the characteristics of small integration, rainproof and low power consumption, making the entire portable station more concise while meeting performance requirements, thereby improving the portability of the system.

[0088] In addition, combined with the Figure 2 The X-band high frequency box includes a DC-DC power supply 217, a frequency synthesis module 216, a radio frequency switch 213, an X-band telemetry down-conversion module 214, an X-band data transmission down-conversion module 215, a calibration and self-test module 212, and a monitoring module 211.

[0089] The DC-DC power supply 217 is used to supply power to the frequency synthesis module 216, the RF switch 213, the X-band telemetry down-conversion module 214, the X-band data transmission down-conversion module 215, the calibration and self-test module 212, and the monitoring module 211;

[0090] The monitoring module 211 is used to monitor and control the working status of the RF switch 213, the X-band telemetry down-conversion module 214, the X-band data transmission down-conversion module 215 and the calibration self-test module 212 according to the parameters output by the station monitoring device 5;

[0091] Among them: the monitoring module 211 monitors the working status of each module according to the parameters issued by the station monitoring station, including input and output operating frequency, switch position, whether the calibration module is output, calibration input and output frequency, etc., and reports any abnormal working of the module to the station control device in the form of an alarm;

[0092] The frequency synthesis module 216 is used to send corresponding local oscillator signals to the X-band telemetry down-conversion module 214, the X-band data transmission down-conversion module 215 and the calibration and self-test module 212 respectively according to the working frequency sent by the monitoring module 211, wherein the local oscillator signals include the local oscillator L01 required by the X-band data transmission down-conversion module 215 or the local oscillators L02 and L03 required by the X-band telemetry down-conversion module 214. If a calibration and self-test signal is required, local oscillators L04 and L05 need to be generated and sent to the calibration and self-test module 212;

[0093] The calibration and self-test module 212 is used to down-convert the power amplifier coupled signal output by the X-band BUC device 2 according to the control instructions sent by the monitoring module 211 and the corresponding local oscillator signal, and output the converted test signal to the X-band LNA1 and the X-band LNA2 respectively;

[0094] The RF switch 213 is used to select the number of RF signals output to the X-band telemetry down-conversion module 214 and the X-band data transmission down-conversion module 215 according to the control instruction sent by the monitoring module 211; one of the RF signals can be sent to the X-band telemetry down-conversion module 214 and the X-band data transmission down-conversion module 215 at the same time, or two RF signals can be sent to the X-band telemetry down-conversion module 214 and the X-band data transmission down-conversion module 215 respectively.

[0095] The X-band telemetry down-conversion module 214 and the X-band data transmission down-conversion module 215 are used to perform frequency conversion processing on the radio frequency signal and the corresponding local oscillator signal respectively according to the working parameters sent by the monitoring module, and output them to the portable baseband 4;

[0096] Specifically, the X-band data transmission down-conversion module 215 mixes and filters the local oscillator L01 output by the frequency synthesizer module 216 according to the operating frequency, signal bandwidth and other parameters issued by the monitoring module 211, and converts any downlink RF signal from 7.7GHz to 9.0GHz into a 1.2GHz intermediate frequency.

[0097] Similarly, the X-band telemetry down-conversion module 214 and the calibration and self-test module 212 perform frequency conversion output according to the parameter instructions issued by the monitoring module 211 .

[0098] In addition, based on the above embodiments, the main technical indicators of this portable integrated satellite ground station are as follows: antenna type: positive-fed ring-focus parabolic antenna; antenna aperture: 1.2 meters; antenna base type: XY type; antenna pointing accuracy: better than 1 / 5 half-power beamwidth; antenna tracking capability: capture at an elevation angle greater than 3°, stable tracking at an elevation angle greater than 5°, and the target will not be lost when the program passes over the top; operating frequency range: downlink frequency: 7.7GHz~9.0GHz, step 100kHz; uplink frequency: 7.145GHz~7.25GHz, step 1KHz; system G / T value: ≥14.5+20l g(f / f0)dB / K (f0=8.2GHz, clear sky, pointing to the top); antenna EI RP value: ≥51.5+20l g(f / f0)dBW (f0=7.2GHz, 50W power amplifier); Polarization: simultaneous left-hand and right-hand circular polarization (receive), time-sharing left-hand and right-hand circular polarization (transmit); Modulation: X-band data transmission: BPSK, QPSK; X-band telemetry: non-coherent spread spectrum; X-band remote control: non-coherent spread spectrum; Modulation / demodulation code rate: X-band data transmission: 1Mbps~150Mbps; X-band telemetry: 1kbps~32kbps; X-band remote control: 1kbps~32kbps; Automatic north-seeking and positioning: Automatic north-seeking accuracy: better than 0.2°; Positioning accuracy: better than 5m; System weight: less than 60kg (excluding field batteries); The total time required for two adults to deploy the entire system, complete self-test, and reach a mission-capable state is less than 25 minutes, and the time required for two adults to withdraw the system is less than 20 minutes.

[0099] When implementing the X-band portable integrated satellite ground station described in the present invention, combined with hardware implementation and without loss of generality, taking a commercial aerospace company's X-band low-orbit remote sensing satellite as an example, the satellite orbit altitude is 500 km. The working steps of the portable integrated measurement, control, and data transmission ground station are given as follows:

[0100] The portable measurement, control and data transmission integrated ground station equipment is deployed, and the antenna is quickly assembled; the system is connected to the mains or UPS, and the entire system is powered on for self-test; the station monitoring device 5 resolves conflicts based on the mission plan (data transmission mission) and satellite ephemeris data of the operation control center to form an in-station work plan. Before the satellite passes, the station monitoring device 5 issues a mission macro command, and the antenna servo feed device 1 controls the antenna to the designated position and waits according to the antenna guidance data; when the satellite passes, the antenna servo feed device 1 uses a program tracking method to point to the target and receive the downlink data transmission signal; the antenna sends the received X-frequency left and right rotation signals to the low-noise The amplifier performs filtering and amplification, and then sends the signal to the X-band high-frequency box to select the left and right rotation signals. The selected RF signal is sent to the X-band digital transmission down-conversion module 215 for down-conversion, and the intermediate frequency 1200MHz is output and sent to the portable measurement and control portable baseband 4. The portable baseband 4 dynamically loads the digital transmission mode program according to the digital transmission task issued by the station monitoring equipment 5, and performs demodulation, decoding, bit synchronization, frame synchronization, descrambling and other processing on the signal, completes the reception and processing of the digital transmission data and stores the digital transmission data locally; when the task is completed, the antenna completes the collection of the antenna according to the program file, and the entire system is on standby;

[0101] If no other tasks are required, the system withdrawal process is executed. For example, when executing the measurement and control task, the station monitoring device 5 issues the measurement and control task macro command. Before the satellite passes, the servo feed device 1 controls the antenna to the specified position and waits according to the antenna guidance data. The portable baseband 4 loads the measurement and control mode. When the satellite passes, the antenna servo feed device 1 uses the program tracking method to point to the target and receive the downlink telemetry signal; the antenna sends the received X-frequency left and right rotation signals to the low noise amplifier for filtering and amplification, and then sends them to the X-band high frequency box for selection of the left and right rotation signals. The selected RF signal is sent to the X-band telemetry down conversion module 214 for down conversion, and the output intermediate frequency is 70MHz. The portable baseband 4 is then sent to the baseband. The portable baseband 4 is loaded with the measurement and control mode, and performs demodulation, decoding, bit synchronization, frame synchronization, and descrambling on the signal, completing the reception and processing of the telemetry signal and storing the data locally. At the same time, the portable baseband 4 completes channel coding according to the remote control command issued by the station control device 5, and outputs a modulated 70MHz intermediate frequency signal after modulation. The X-band BUC device 2 changes the frequency of the uplink 70MHz and amplifies the uplink RF signal by 50W, and injects it into the satellite through the antenna. When the task is completed, the station control device 5 generates a work report and reports it to the operation control center. If no other tasks are required, the system withdrawal process is executed.

[0102] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. An X-band portable integrated satellite ground station, characterized by: It includes antenna feed equipment (1), X-band BUC equipment (2), downlink receiving channel equipment (3), portable baseband (4) and station monitoring equipment (5); The uplink radio frequency input end of the antenna feed device (1) is connected to the output end of the X-band BUC device (2), and the downlink radio frequency output end of the antenna feed device (1) is connected to the radio frequency input end of the downlink receiving channel device (3); The antenna feed device (1) includes an antenna feed component, a servo control component, an antenna bracket, a positioning and timing module, and a power supply module, wherein the antenna feed component includes a parabolic antenna and an X-band feed source, and the X-band feed source is used to receive signals from medium and low orbit remote sensing satellites and transmit the satellite signals to a downlink receiving channel device (3), and transmit the remote control instructions sent by the X-band BUC device (2) to the satellite via the parabolic antenna; The servo control component is used to monitor and control the attitude of the parabolic antenna; The top of the column of the antenna bracket is used to install the parabolic antenna, the inside of the column of the antenna bracket is used to install the power module, the timing and positioning module and the servo control board, and the bottom of the column is used to install the support legs; The positioning and timing module is capable of providing positioning, orientation and timing signals for the station monitoring device (5); The antenna feed device (1) adopts a program tracking target satellite method, including a fast automatic angle calibration method, firstly, the positioning and timing module provides an initial angle reference; Then, in the program-guided working mode, the antenna real-time angle is corrected twice by superimposing the azimuth or elevation offset and comparing the AGC voltage; Finally, the local measurement system angle data is automatically and accurately corrected in real time based on the precise orbit data sent by the central station control and the antenna's own error voltage; The intermediate frequency input terminal of the X-band BUC device (2) is connected to the intermediate frequency output terminal of the portable baseband (4), and the power amplifier coupling output terminal of the X-band BUC device (2) is connected to the test input terminal of the downlink receiving channel; The intermediate frequency output end of the downlink receiving channel device (3) is connected to the input end of the portable baseband (4), and the downlink receiving channel device (3) converts the power amplifier coupling signal sent by the X-band BUC device (2) into a downlink radio frequency test signal and amplifies it; The downlink receiving channel device (3) includes an X-band LNA1, an X-band LNA2 and an X-band high-frequency box, wherein the signal input ends of the X-band LNA1 and the X-band LNA2 are both communicatively connected to the antenna feed device (1), and the signal output ends of the X-band LNA1 and the X-band LNA2 are both communicatively connected to the X-band high-frequency box; The X-band high frequency box is used to select and frequency-convert the radio frequency signals output by the X-band LNA1 and the X-band LNA2, and frequency-convert the power amplifier coupling signal output by the X-band BUC device (2), and send it to the downlink channel for self-test; The X-band high frequency box includes a monitoring module (211), a calibration and self-test module (212), a radio frequency switch (213), an X-band telemetry down-conversion module (214), an X-band data transmission down-conversion module (215), a frequency synthesis module (216) and a DC-DC power supply (217). The monitoring module (211) is used to monitor and control the working states of the radio frequency switch (213), the X-band telemetry down-conversion module (214), the X-band data transmission down-conversion module (215) and the calibration self-test module (212) according to the parameters output by the station monitoring device (5); The frequency synthesis module (216) is used to send corresponding local oscillator signals to the X-band telemetry down-conversion module (214), the X-band data transmission down-conversion module (215) and the calibration self-test module (212) respectively according to the operating frequency sent by the monitoring module (211); The calibration and self-test module (212) is used to down-convert the power amplifier coupling signal output by the X-band BUC device (2) according to the control instruction sent by the monitoring module (211) and the corresponding local oscillator signal, and output the converted test signal to the X-band LNA1 and the X-band LNA2 respectively; The radio frequency switch (213) is used to selectively output the input radio frequency signal to the X-band telemetry down-conversion module (214) and the X-band data transmission down-conversion module (215) according to the control instruction sent by the monitoring module (211); The X-band telemetry down-conversion module (214) and the X-band data transmission down-conversion module (215) are used to perform frequency conversion and amplification processing on the local oscillator signal according to the working parameters sent by the monitoring module (211), generate corresponding measurement and control and data transmission signals, and output them to the portable baseband (4); The DC-DC power supply (217) is used to supply power to the frequency synthesis module (216), the radio frequency switch (213), the X-band telemetry down-conversion module (214), the X-band data transmission down-conversion module (215), the calibration and self-test module (212), and the monitoring module (211); The station monitoring device (5) respectively exchanges information with the antenna feed device (1), the X-band BUC device (2), the downlink receiving channel device (3) and the portable baseband (4).

2. The X-band portable integrated satellite ground station according to claim 1, wherein: The reflecting surface of the parabolic antenna adopts an 8-petal assembly structure, and each reflecting surface is connected by a positioning pin and a locking mechanism.

3. The X-band portable integrated satellite ground station according to claim 2, characterized in that: The reflecting surface is made of a carbon fiber panel.

4. The X-band portable integrated satellite ground station according to claim 1, wherein: The parabolic antenna mount adopts an XY type.

5. The X-band portable integrated satellite ground station according to claim 1, wherein: The antenna bracket adopts a tripod.

6. The X-band portable integrated satellite ground station according to claim 1, characterized in that: The X-band BUC device (2) comprises a DC power supply unit, an up-conversion module, a power amplifier module and a monitoring unit, wherein the DC power supply unit is used to supply power to the up-conversion module, the power amplifier module and the monitoring unit; The up-conversion module is used to up-convert the uplink intermediate frequency signal transmitted by the portable baseband (4); The power amplifier module is used to amplify the power of the uplink radio frequency after up-conversion, and send the amplified radio frequency signal to the antenna feed device (1); The monitoring unit is used to monitor and control the DC power supply unit, the up-conversion module and the power amplifier module.

7. The X-band portable integrated satellite ground station according to claim 6, characterized in that: The up-conversion module adopts a secondary frequency conversion method.

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