Construction method of Beidou ground-based augmentation base station network compatible with multi-satellite system

Abstract

The invention relates to the technical field of ground-based augmentation base station layout, in particular to a Beidou ground-based augmentation base station network construction method compatible with a multi-satellite system, which comprises the following steps: carrying out site distribution setting of base stations according to the actual condition along a railway; based on the maximum convex polyhedron criterion, newly building foundation enhancement base stations according to the average spacing of 10-20 km, transforming the built base stations, and constructing a Beidou foundation enhancement base station network with the newly built foundation enhancement base stations; a data communication subsystem, a control center subsystem and a user service subsystem are constructed for a Beidou ground-based augmentation base station network. The Beidou ground-based augmentation base station network compatible with the multiple satellite systems can support multiple satellite systems at the same time, the problem that the compatibility of multiple systems is insufficient in an existing scheme is effectively solved, the positioning precision is improved, and the service range is widened.

Description

Technical Field

[0001] The present invention relates to the technical field of ground-based augmented reference station deployment, and in particular to a Beidou ground-based augmented reference station network construction method compatible with a multi-satellite system. Background Art

[0002] With the widespread adoption of the Beidou satellite navigation system, the ground-based augmentation system (GABS) is gradually evolving towards compatibility with multiple satellite systems. For example, the Beidou GABS supports not only Beidou satellite signals, but also GPS, GLONASS, Galileo, and other satellite systems. The GABS provides high-precision positioning services through a network of ground-based reference stations. Using network technology, it enables real-time data transmission between the stations and control centers, supporting automated operation and remote monitoring. It is widely used in railways, ports, agriculture, surveying, and other fields.

[0003] However, due to technical differences between existing ground-based augmentation systems, there is insufficient compatibility between systems, making it difficult to achieve seamless docking. In addition, some systems did not fully consider future expansion needs during design, resulting in technical bottlenecks when adding new base stations or users. At the same time, the amount of data generated by the base station network is huge and involves a large amount of sensitive data, which places high demands on data storage, data processing capabilities, data security and confidentiality. In addition, the service quality of base stations in different regions and application scenarios varies, making it difficult to meet the needs of high-precision positioning. Summary of the Invention

[0004] In view of this, the present invention proposes a Beidou ground-based augmentation reference station network construction method compatible with multiple satellite systems to solve the problems existing in the above-mentioned prior art.

[0005] To achieve the above objectives, the present invention proposes a method for constructing a BeiDou ground-based augmentation reference station network compatible with a multi-satellite system, which is characterized by comprising:

[0006] The base station site distribution is set up according to the actual situation along the railway;

[0007] Based on the maximum convex polyhedron criterion, new ground-based enhanced reference stations are built with an average spacing of 10-20 km;

[0008] Renovate the completed base stations and build a BeiDou ground-based augmentation base station network together with the newly built ground-based augmentation stations;

[0009] A data communication subsystem, a control center subsystem, and a user service subsystem are constructed for the Beidou ground-based augmented reference station network.

[0010] Furthermore, the antenna layout of the GNSS receiver of the base station has a satellite visibility condition of an altitude angle of more than 10° above the horizon. Under difficult and complex mountainous environmental conditions, the altitude angle is limited to more than 25°; the ground-based augmented base station is designed to be unmanned and automatically run continuously.

[0011] Furthermore, the construction process of the data communication subsystem includes:

[0012] Build a distributed gigabit network in the data center, a dedicated fiber optic transmission network from the base station to the data center, and a communication network from the data center to the rover users;

[0013] The data center distributed network supports gigabit data transmission of central computers and network equipment, and provides a connection interface for downloading reference station data;

[0014] Sending a processing request to the data center in real time based on the optical fiber transmission network, and the data center promptly broadcasting the differential correction data to the reference station;

[0015] Based on the communication network, the real-time differential correction data is broadcast to the mobile station users in GPRS mode, and the interface service for downloading the base station data is provided in the form of HTTP service through the Internet network.

[0016] Furthermore, the control center subsystem functions include:

[0017] The C / S mode is used to receive data from each base station in real time, and after synchronous processing, real-time baseline solution is performed to calculate the real-time delay and baseline residual; a distributed processing framework and load balancing technology are used to optimize the data processing process; the real-time delay is modeled and a regional ionosphere and troposphere model is established; the base station receiver clock error parameters are estimated based on the base station data and precise satellite clock error; a model is established based on the user's approximate position, and correction data is calculated using residual interpolation and other methods, which are then encoded and broadcast to users in RTCM and other ways; the base station's precise coordinates are calculated in real time using base station data, precise orbits, clock errors and other parameters, and the base station coordinates are monitored.

[0018] Furthermore, based on the control center subsystem, all reference station data are connected to the control center core router through a dedicated line, and divided into two paths through the firewall. One path is imported into the confidential environment for storage, and the other path enters the reference station software through the decryption device for real-time data solution and service.

[0019] Furthermore, based on the control center subsystem, the GNSS receivers of each local augmentation reference station are controlled and the equipment integrity is monitored; the control center server and UPS and other equipment are controlled and the equipment integrity is monitored; the access of real-time users and post-users is monitored to prevent unauthorized access or malicious attacks; the regional ionospheric changes and the coordinate positions of the reference stations are monitored and evaluated in the medium and short term, and when abnormal ionospheric activity or large changes in the reference station coordinates occur, the operator and user are prompted; the real-time and post-user usage is monitored, and the data traffic or usage time of each user is recorded.

[0020] Furthermore, based on the control center subsystem, real-time positioning and navigation services are provided to users through 4G / 5G transmission, and the number of users served simultaneously is not limited within the scope permitted by the basic resource capabilities; the base station raw data download service is provided on the intranet through FTP; the base station raw data is provided to management users, and the data file format is RINEX; and post-processing services such as control network solution, coordinate conversion, and normal height conversion are provided to management users.

[0021] Furthermore, the construction process of the user service subsystem includes:

[0022] Build service distribution, user terminals, and user service functions; the service distribution includes broadcasting real-time positioning services to users in Ntrip, TCP / IP, and one-way broadcast mode; the user terminals include RTK receivers, RTD portable terminals, vehicle-mounted terminals, airborne terminals, wearable portable terminals, and terminal software; the user services include user authority management at all levels, dynamic adjustment of system operating parameters, and provision of real-time or quasi-real-time positioning services and post-event high-precision positioning services to users.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] The Beidou ground-based augmented reference station network compatible with multiple satellite systems proposed in the present invention can simultaneously support satellite systems such as BDS, GPS, GLONASS, and Galileo, effectively solving the problem of insufficient multi-system compatibility in existing solutions and improving positioning accuracy and service range. The present invention rationally plans the site spacing by optimizing the layout and rapid deployment of reference stations. In addition, the maximum convex polyhedron criterion can shorten the layout time and meet the needs of emergency scenarios. The present invention proposes to improve data processing efficiency through a distributed processing framework and load balancing technology, and introduces a data decryption subsystem to solve data security and confidentiality issues. The present invention supports multi-user real-time positioning services and high-precision post-processing by designing a user service subsystem, and realizes functions such as user authority management and fee management, which significantly improves the quality of user services. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Various other advantages and benefits will become apparent to those skilled in the art by reading the detailed description of the preferred embodiment below. The accompanying drawings are only for the purpose of illustrating the preferred embodiment and are not to be considered as limiting the present invention. In the accompanying drawings:

[0026] Figure 1 Schematic diagram of the process of establishing a BeiDou ground-based augmented reference station network in an embodiment of the present invention;

[0027] Figure 2 A diagram showing a connection structure of site equipment in an embodiment of the present invention;

[0028] Figure 3 This is a network structure diagram of the control center in an embodiment of the present invention. DETAILED DESCRIPTION

[0029] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that, unless there is a conflict, the embodiments of the present disclosure and the features described in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0030] This embodiment proposes a BeiDou ground-based augmented reference station network construction method compatible with multiple satellite systems, such as Figure 1 As shown, including:

[0031] The base station site distribution is set up according to the actual situation along the railway;

[0032] Based on the maximum convex polyhedron criterion, new ground-based enhanced reference stations are built with an average spacing of 10-20 km;

[0033] Renovate the completed base stations and build a BeiDou ground-based augmentation base station network together with the newly built ground-based augmentation stations;

[0034] The data communication subsystem, control center subsystem and user service subsystem are constructed for the Beidou ground-based augmentation base station network respectively.

[0035] The construction of the BeiDou Ground-Based Augmentation System reference station network described in this embodiment mainly includes reference station site selection, equipment installation and debugging, data communication link construction between the control center and the reference stations and user terminals, and the construction of the control center and service center.

[0036] Solution Design

[0037] The system primarily includes the Reference Station Sub-System (RSS), the Data Communication Sub-System (DCS), the System Monitoring and Analysis Center (SMAC), the User Application Sub-System (UAS), and the Data Decryption Sub-System (DDS). The definitions and functions of each subsystem are shown in Table 1.

[0038] Table 1

[0039]

[0040] Base station subsystem

[0041] Station distribution is carried out based on the actual conditions along the railway. Based on the idea of ​​"Beidou compatibility, optimized layout, and improved services", and in accordance with relevant station construction specifications, 45 new ground-based augmentation stations are built. At the same time, the 6 completed base stations are renovated and incorporated into the Beidou base station network for unified management. The maximum convex polyhedron criterion is adopted to ensure that the station distribution can maximize the coverage and improve the positioning accuracy. Integrity monitoring equipment is deployed at each station with an average spacing of about 10-20km, so as to achieve a uniform and reasonable strip structure of the station network and effectively improve the overall service quality of the system.

[0042] like Figure 2 As shown in Figure 1, a base station generally consists of outdoor observation equipment and indoor instruments and equipment. Outdoor equipment includes lightning protection equipment, observation piers, and choke antennas. Indoor equipment primarily consists of a cabinet and battery pack, including the base station GNSS receiver, network equipment, surge protection equipment, and UPS equipment, all installed within the cabinet. Indoor and outdoor equipment are independent of each other and require connection via data feeders. All stations utilize domestically produced core technology equipment and GNSS equipment compatible with multiple satellite systems, including BDS, GPS, GLONASS, and Galileo. These equipment form the railway Beidou satellite navigation and positioning base station network subsystem, providing differential positioning services for multiple systems, including BDS, GPS, GLONASS, and Galileo. Specific equipment and functional specifications are shown in Table 2.

[0043] Table 2

[0044]

[0045] The base station receiver antenna should be positioned to provide satellite visibility at an elevation angle of at least 10°. In challenging mountainous environments, the elevation angle can be relaxed by 25°. The base station is designed for unattended, automatic, and continuous operation, with an annual reliability rate exceeding 95%.

[0046] Data communication subsystem

[0047] The data communication subsystem consists of three parts: the first is the distributed gigabit network of the data center, the second is the base station optical fiber transmission network established from the base station to the data center, and the third is the communication network broadcast from the data center to the mobile station users.

[0048] (1) Functional implementation and design

[0049] 1) The data center distributed network supports gigabit data transmission of central computers and network equipment, and provides a connection interface for external users to download base station data.

[0050] 2) Each base station and data center uses network resources to build a dedicated fiber optic transmission network and 3G / 4G / 5G wireless network for base station data transmission.

[0051] 3) Mobile station users can send processing requests to the data center in real time, and the data center will broadcast the differential correction data to users in a timely manner.

[0052] 4) The network system adopts an open and standardized structure and has good functional expansion and upgrade capabilities.

[0053] 5) Have certain network security mechanisms.

[0054] (2) Base station wired private network transmission

[0055] In this embodiment, the Beidou reference station network uses a dedicated network along the railway for data transmission to achieve communication between the reference station and the data center.

[0056] (3) User service data broadcasting network

[0057] This embodiment broadcasts data to external users in two ways: broadcasting real-time differential correction data to mobile station users via GPRS, and providing users with an interface service for downloading base station data later via the Internet in the form of HTTP service.

[0058] Control center subsystem

[0059] like Figure 3 As shown, the control center is the core unit of the railway Beidou ground-based augmentation system, which consists of computers and network systems, software systems and power systems, and is connected to each base station through a dedicated network.

[0060] As the core, the control center is responsible for the access and processing of base station data streams, the management and maintenance of the entire system, the generation of system application services and information services, etc.

[0061] (1) Data processing

[0062] 1) Receive data from each reference station in real time in C / S mode, perform real-time baseline solution after synchronous processing, and calculate parameters such as real-time delay of regional ionosphere, troposphere, and baseline residual;

[0063] 2) Model the real-time delays in the ionosphere and troposphere and establish regional ionosphere and troposphere models; estimate the base station receiver clock error parameters based on base station data and precise satellite clock errors;

[0064] 3) Build a model based on the user's approximate position, calculate correction data using methods such as residual interpolation, and broadcast it to the user through RTCM or other means after encoding;

[0065] 4) Use the reference station data, precise orbit, clock error and other parameters to calculate the precise coordinates of the reference station in real time and monitor the coordinates of the reference station.

[0066] (2) Operation management

[0067] 1) Control and monitor the integrity of the GNSS receivers at each base station;

[0068] 2) Control and monitor the integrity of control center servers, UPS and other equipment;

[0069] 3) Monitor the access of real-time and post-user users to prevent unauthorized access or malicious attacks;

[0070] 4) Conduct short- to medium-term monitoring and assessment of regional ionospheric changes and reference station coordinate positions, and alert operators and users when abnormal ionospheric activity or significant changes in reference station coordinates occur;

[0071] 5) Monitor real-time and post-event user usage, record each user's data traffic or usage time, and establish an operating mechanism based on this and in accordance with policies and regulations;

[0072] 6) It can adapt to the increase in the number of base stations and users to a certain extent.

[0073] (3) Information Services

[0074] 1) Provide users with different types of real-time positioning and navigation services through 4G and other means, without limiting the number of users served simultaneously within the scope of basic resource capabilities;

[0075] 2) Provide base station raw data download service on the intranet through FTP or other methods;

[0076] 3) Provide the original data of the base station to the authorized users, and the data file format is RINEX;

[0077] 4) Provide post-processing services such as control network solution, coordinate conversion, and normal height conversion to authorized users.

[0078] (4) Network management

[0079] All base station data is connected to the core router of the control center through a dedicated line, and is divided into two paths through the firewall. One path is imported into a confidential environment for storage, and the other path enters the base station software through a decryption device for real-time data solution and service.

[0080] (5) Software and hardware configuration

[0081] Typically, a base station device processes 12 GB of data per month, so the server side should be equipped with a disk array cabinet as needed. The storage space required by 51 base stations per month is approximately 650 GB.

[0082] The software and hardware mainly include operating systems, databases, disaster recovery systems, virtualization systems, base station management and service software, servers, disk arrays, networks and security software and hardware equipment, etc.

[0083] User service subsystem

[0084] The user subsystem mainly includes functional modules such as service distribution, user terminal, and user service.

[0085] (1) Service distribution

[0086] Broadcast real-time positioning services to users in various ways such as Ntrip, TCP / IP, and one-way broadcast.

[0087] (2) User Terminal

[0088] It consists of an RTK receiver, an RTD portable terminal, a vehicle-mounted terminal, an airborne terminal, a wearable portable terminal and terminal software.

[0089] (3) User Services

[0090] It is mainly composed of a user service management system and should implement the following functions:

[0091] 1) Implement authority management for users at all levels, including senior administrators, unit administrators, and measurement users, and generate user information query reports as needed; implement real-time monitoring of user locations, trajectories, and operating areas based on maps; and effectively manage user fees.

[0092] 2) Implement dynamic adjustment of system operating parameters, including user group level, system IP, and database.

[0093] 3) Provide users with real-time or quasi-real-time positioning services and post-event high-precision positioning services to meet users' needs for high-precision location information, such as benchmark services.

[0094] Beidou Ground-Based Augmentation System Platform Functions

[0095] The BeiDou Ground-Based Augmentation System platform should be based on independently developed core technologies and be able to meet the system's solution and service requirements. By incorporating multiple technologies such as load balancing and DC active-active, the system considers a distributed processing framework for each core business layer under the access load of a large-scale base station network. By adjusting and optimizing the logical processing flow of GNSS data, computer computing efficiency is improved under high-load conditions, enabling large-scale system applications. At the same time, the software's distributed architecture can meet customers' needs for expanding large-scale applications and meet customized service requirements in related industries and fields.

[0096] (1) System interface design

[0097] Base station network data is divided into two categories (relative to system users): internal and external data. Internal data refers to traffic data exchanged within the system and is not publicly available; external data refers to traffic data exchanged between the system and users. Both types of data are processed and transformed by various subsystems. The flow and control of all types of data in the system are completely automatic, requiring no human intervention. If data flow is blocked, the system will issue an alarm after failed attempts, prompting the operator to troubleshoot the problem. Once the problem is resolved, the system will resume normal operation.

[0098] 1) Internal data interface

[0099] Internal data between the various subsystems of the base station network includes data exchanged between the base station network and the data center, and within the data center. The data interfaces between the two are shown in Tables 3 and 4.

[0100] Table 3

[0101]

[0102] Table 4

[0103]

[0104] 2) External data interface

[0105] External data is generated by the base station network system data center to broadcast real-time data to users, that is, the service results of the system. The specific interface is shown in Table 5.

[0106] Table 5

[0107]

[0108]

[0109] (2) System software design

[0110] Based on the data interface designed above, the software of the entire system includes base station management software, operating system software, database software, precision post-processing software, etc. The explanation and configuration of each software component are shown in Table 6.

[0111] Table 6

[0112] category Function Remark Base station management software Base station data reception, solution and external services Joint Development operating system software System environment construction Business Software Database management software Database Platform Business Software Precision post-processing software Precisely solve the system frame coordinates Business Software

[0113] Implementation Process

[0114] (1) Data collection, design writing and demonstration

[0115] Based on a thorough study and reference to the preliminary research content, practical experience and data of the railway system satellite positioning continuous operation integrated application service system, combined with the construction of the railway Beidou satellite navigation and positioning base station network and the actual infrastructure of various industry systems, the technical design book was completed in accordance with national standards and passed the review.

[0116] (2) Software and hardware equipment procurement

[0117] System equipment includes specialized equipment, general equipment, and other supporting equipment. Through testing and comparison, equipment with performance and functionality that meets the requirements is selected and purchased and tendered in a unified manner.

[0118] (3) Software and hardware installation and system debugging

[0119] Install and debug software and hardware at the control center and sites. Transmit data between the base station and the data service system via the data transmission link.

[0120] (4) Coordinate calculation and assignment

[0121] Calculate the coordinates of the base station and assign the initial values ​​to the system.

[0122] (5) System integration testing

[0123] Conduct system testing according to system testing requirements and test the system's performance on-site and through simulated users.

[0124] Subsystem implementation

[0125] System construction requires ensuring system scalability and compatibility. Standardized base station hardware and software, auxiliary facilities, and various information platforms must be used, taking into account requirements such as expanded coverage, expanded service areas and users, the addition of new satellite navigation systems, and the expansion of GNSS positioning technology.

[0126] (1) Reference station subsystem

[0127] All base stations will be replaced with GNSS receivers compatible with navigation and positioning systems such as BDS, GPS, GLONASS, and Galileo. This work will primarily include equipment installation and commissioning, communication network equipment commissioning, line commissioning, and installation of corner reflectors and image markers. Specific installation and commissioning requirements must be met:

[0128] 1) Install the GNSS receiver. Connect the original receiver and Beidou receiver in parallel to the antenna feed line lightning arrester through a power splitter. Then connect the antenna feed line. Configure the GNSS receiver's parameters or functions, such as satellite tracking, IP address, real-time data streaming, raw observation data storage, and data FTP push. Connect the GNSS receiver to the switch through the network lightning arrester.

[0129] 2) Check the satellite tracking status of the GNSS receiver, the ephemeris update time of each satellite system, the number of satellites tracked by each satellite system, the signal-to-noise ratio, and the single-point positioning coordinates.

[0130] 3) Check the data flow sending status, original data saving status, and test the FTP push function.

[0131] 4) All equipment of the base station is placed in the cabinet of the computer room, and the cables are connected to the cabinet from the bottom of the computer room.

[0132] 5) Signal lines and power lines should be laid separately, and try not to cross or overlap to reduce the impact on each other.

[0133] 6) The connection between the signal line and the equipment must be fixed to ensure the reliability of the connection.

[0134] 7) The power line socket must have good contact and should comply with the testing standards of the relevant departments.

[0135] 8) Cables should be fixed with wiring racks or plastic wire clamps, and protective measures should be taken at bends to avoid potential faults caused by scratches on the cable sheath.

[0136] 9) Photos of the equipment installation process must be taken on-site as required.

[0137] (2) Communication subsystem

[0138] This embodiment fully utilizes existing data transmission dedicated lines, which adopt SDH technology.

[0139] (3) Control center system

[0140] The control center system primarily involves upgrading, updating, and maintaining the center's data security and management applications, computer room servers, firewalls, routers, switches, and data storage arrays. It also deploys base station management software, base station data flow decryption software, and data distribution service software. This ensures secure data access and external services, enabling diversified output of popular data.

[0141] (4) User service subsystem

[0142] The user service subsystem includes the construction of system functional modules such as service distribution, data storage, and user services. In accordance with the relevant requirements of railway applications, research and establish a popular and socialized service model and mechanism for base station network data to promote the popularization and universal application of the Beidou system.

[0143] Based on the system's existing hardware and network architecture, the user service management subsystem will be optimized by fully utilizing existing dedicated network transmission links. Relying on the existing data communication network architecture between the data processing control center, base stations, and mobile stations, while ensuring information security, new service models will be explored between the control center and other location application platforms, expanding service offerings and improving service quality. This will include user service management, service product management, and system status publishing and management.

[0144] The above embodiments are only used to build the user service subsystem, including system functional modules such as service distribution, data storage, and user services. In accordance with the relevant requirements of railway applications, research and establish a popularization and socialization service model and mechanism for base station network data to promote the popularization and universal application of the Beidou system.

[0145] Unless otherwise indicated, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein may also be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of any conflict with any incorporated document, the contents of this specification shall prevail.

[0146] Finally, it should be noted that the above-described embodiments are only specific implementations of the present invention, which are used to illustrate the technical solutions of the present invention, rather than to limit them. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the above-described embodiments, those skilled in the art should understand that any person skilled in the art can modify or easily conceive of changes to the technical solutions described in the above-described embodiments within the technical scope disclosed by the present invention, or replace some of the technical features therein with equivalents. Such modifications, changes, or replacements do not deviate from the spirit and scope of the technical solutions of the embodiments of the present invention. They should all be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. A method for constructing a BeiDou ground-based augmentation reference station network compatible with multiple satellite systems, characterized in that: include: The base station site distribution is set up according to the actual situation along the railway; Based on the maximum convex polyhedron criterion, new ground-based enhanced reference stations are built with an average spacing of 10-20 km; Renovate the completed base stations and build a BeiDou ground-based augmentation base station network together with the newly built ground-based augmentation stations; A data communication subsystem, a control center subsystem, and a user service subsystem are constructed for the Beidou ground-based augmented reference station network.

2. The method for constructing a BeiDou ground-based augmented reference station network compatible with a multi-satellite system according to claim 1, characterized in that: The ground-based enhanced reference station includes outdoor observation equipment and indoor instruments and equipment; the outdoor observation equipment includes lightning protection equipment, observation piers, and choke antennas; the indoor instruments and equipment include reference station GNSS receivers, network equipment, surge protection equipment, and UPS equipment.

3. The method for constructing a BeiDou ground-based augmented reference station network compatible with a multi-satellite system according to claim 2, characterized in that: The antenna layout of the GNSS receiver of the base station has a satellite visibility condition of an altitude angle of more than 10° above the horizon. Under difficult and complex mountainous environment conditions, the altitude angle is limited to more than 25°; the ground-based augmented base station is designed to be unmanned and automatically run continuously.

4. The method for constructing a BeiDou ground-based augmented reference station network compatible with a multi-satellite system according to claim 1, wherein: The construction process of the data communication subsystem includes: Build a distributed gigabit network in the data center, a dedicated fiber optic transmission network from the base station to the data center, and a communication network from the data center to the rover users; The data center distributed network supports gigabit data transmission of central computers and network equipment, and provides a connection interface for downloading reference station data; Sending a processing request to the data center in real time based on the optical fiber transmission network, and the data center promptly broadcasting the differential correction data to the reference station; Based on the communication network, the real-time differential correction data is broadcast to the mobile station users in GPRS mode, and the interface service for downloading the base station data is provided in the form of HTTP service through the Internet network.

5. The method for constructing a BeiDou ground-based augmented reference station network compatible with a multi-satellite system according to claim 1, characterized in that: The control center subsystem functions include: The C / S mode is used to receive data from each base station in real time, and after synchronous processing, real-time baseline solution is performed to calculate the real-time delay and baseline residual; a distributed processing framework and load balancing technology are used to optimize the data processing process; the real-time delay is modeled and a regional ionosphere and troposphere model is established; the base station receiver clock error parameters are estimated based on the base station data and precise satellite clock error; a model is established based on the user's approximate position, and correction data is calculated using residual interpolation and other methods, which are then encoded and broadcast to users in RTCM and other ways; the base station's precise coordinates are calculated in real time using base station data, precise orbits, clock errors and other parameters, and the base station coordinates are monitored.

6. The method for constructing a BeiDou ground-based augmented reference station network compatible with a multi-satellite system according to claim 1, characterized in that: Based on the control center subsystem, all base station data are connected to the control center core router through a dedicated line, and are divided into two paths through the firewall. One path is imported into a confidential environment for storage, and the other path enters the base station software through a decryption device for real-time data solution and service.

7. The method for constructing a BeiDou ground-based augmented reference station network compatible with a multi-satellite system according to claim 1, characterized in that: Based on the control center subsystem, the GNSS receivers of each local augmentation base station are controlled and the equipment integrity is monitored; the control center server and UPS and other equipment are controlled and the equipment integrity is monitored; the access of real-time users and post-users is monitored to prevent unauthorized access or malicious attacks; the regional ionospheric changes and the coordinate positions of the base stations are monitored and evaluated in the medium and short term, and when abnormal ionospheric activity or large changes in the base station coordinates occur, the operator and user are prompted; the real-time and post-user usage is monitored, and the data flow or usage time of each user is recorded.

8. The method for constructing a BeiDou ground-based augmented reference station network compatible with a multi-satellite system according to claim 1, characterized in that: Based on the control center subsystem, real-time positioning and navigation services are provided to users through 4G / 5G transmission, and the number of users served simultaneously is not limited within the scope permitted by basic resource capabilities; base station raw data download services are provided on the intranet through FTP; base station raw data are provided to management users, and the data file format is RINEX; and post-processing services such as control network solution, coordinate conversion, and normal height conversion are provided to management users.

9. The method for constructing a BeiDou ground-based augmented reference station network compatible with a multi-satellite system according to claim 1, characterized in that: The construction process of the user service subsystem includes: Build service distribution, user terminals, and user service functions; the service distribution includes broadcasting real-time positioning services to users in Ntrip, TCP / IP, and one-way broadcast mode; the user terminals include RTK receivers, RTD portable terminals, vehicle-mounted terminals, airborne terminals, wearable portable terminals, and terminal software; the user services include user authority management at all levels, dynamic adjustment of system operating parameters, and provision of real-time or quasi-real-time positioning services and post-event high-precision positioning services to users.

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