Navigation positioning system for plateau waters and base station distribution mode

Abstract

The invention discloses a navigation and positioning system for a plateau water area, which comprises a hardware layer for multi-source data acquisition, data perception and physical support and comprises base station equipment and a user terminal; the data layer is used for information transmission and intelligent processing and comprises a communication network and a data processing center; the service layer is used for scene application and decision support and comprises a positioning service mode and an abnormity monitoring mode; and the hardware layer, the data layer and the service layer realize cooperation through a multi-stage data flow and control mechanism. The invention also discloses a base station distribution mode of the Beidou positioning system in the plateau region, which comprises the following steps of: (1) arranging one base station along the main axis of a river at an interval of 50-80km, and laying a global reference network; and (2) respectively laying area reinforcing nets according to different area sections. The navigation positioning system provided by the invention provides high-reliability technical support for safety management of plateau waters.

Description

Technical Field

[0001] This invention relates to the field of satellite positioning technology, and more specifically, to a navigation and positioning system and base station distribution method for use in plateau waters. Background Technology

[0002] To facilitate satellite signal reception, conventional multi-mode, multi-satellite reference stations are typically built on the rooftops of high-rise buildings or in outdoor locations with minimal obstructions. The reference station positioning system generally consists of a power supply system, a terminal system, and a management system. The power supply system typically uses indoor wiring to provide power to the reference station. The terminal system comprises receivers, choke antennas, and other equipment. The management system is a visual interface. Conventional reference station systems require periodic manual checks to ensure stable operation and accurate reception of positioning data. However, in high-altitude, unattended areas such as the Lancang River basin, severe weather such as thunderstorms, blizzards, and hurricanes can occur. Traditional technologies rely on dense base stations, which are difficult to deploy in uninhabited areas. Furthermore, convergence times in ionospherically active regions exceed 15 minutes. Additionally, single-system BeiDou positioning often results in positioning errors exceeding 1 meter in canyon areas due to poor satellite visibility. In uninhabited areas, satellite communication data transmission is costly and bandwidth-limited, making it impossible to support the return of raw observation values. Therefore, problems such as low navigation and positioning accuracy, delayed geological disaster early warning, and unreliable communication in uninhabited areas exist. Summary of the Invention

[0003] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a navigation and positioning system and base station distribution method for plateau waters.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] A navigation and positioning system for high-altitude waters, comprising:

[0006] Hardware layer: multi-source data acquisition, data sensing and physical support, including base station equipment and user terminals;

[0007] Data layer: Information transmission and intelligent processing, including communication networks and data processing centers;

[0008] Service layer: Scenario-based applications and decision support, including location service mode and anomaly monitoring mode;

[0009] The hardware layer, the data layer, and the service layer collaborate through a multi-level data flow and control mechanism.

[0010] Furthermore, the base station equipment includes:

[0011] Time synchronization module: Built-in BeiDou / GPS dual-mode atomic clock, achieving network-wide time synchronization through BeiDou satellite signals;

[0012] Environmental monitoring unit: integrates soil moisture sensor and inclinometer to monitor the foundation stability of the base station equipment in real time;

[0013] Remote control interface: Supports RS485 / Modbus protocol with IP67 protection rating, used to adjust antenna elevation angle and transmit power.

[0014] Furthermore, the user terminal includes:

[0015] Multi-mode communication module: Supports 4G / BeiDou RDSS / LoRa three-mode switching, and automatically selects the optimal link based on signal strength;

[0016] Data fusion unit: Employs an extended Kalman filter (EKF) to fuse BeiDou RTK, barometric altimeter, and inertial navigation data.

[0017] Furthermore, the communication network includes:

[0018] Transmission protocols in uninhabited areas: BeiDou short messages use BDS-3RDSS enhanced messages and transmit raw observations through data fragmentation and compression technology; LoRa self-organizing networks use TDMA time division multiple access protocol, setting fixed time slots of 10 minutes / time to reduce the probability of collisions;

[0019] Manned area transmission protocol: based on the RTCM3.3 standard, the observation data is encapsulated and encrypted through NTRIP over HTTPS.

[0020] Furthermore, the data processing center includes:

[0021] Distributed computing cluster: Adopting a Hadoop+Spark architecture, the master node is responsible for PPP-RTK computation, and the slave nodes process ionospheric modeling in parallel.

[0022] Data storage solution: Cold and hot data are stored in a tiered manner, real-time data is stored in a Redis database, and historical data is archived to MinIO object storage.

[0023] Furthermore, the location service mode includes:

[0024] Hybrid positioning engine: Real-time differential positioning generates VRS virtual observations and reduces bandwidth usage through Extended Predicted Orbit (EPO) technology; Post-event precise positioning provides a RINEX 3.04 format download interface and supports an online solution platform, which includes at least one of CSRS-PPP and GAPS.

[0025] QoS Tiered Service: Resources are dynamically allocated based on user permissions, prioritizing the data throughput of geological disaster monitoring terminals.

[0026] Furthermore, the anomaly monitoring mode includes:

[0027] Baseline station health assessment: Design an SNR (signal-to-noise ratio) index model, the specific formula is as follows:

[0028]

[0029] Wherein, SNRscore represents the comprehensive score index of the base station's signal quality; the smaller the value, the worse the signal. An alarm is triggered when SNRscore < 2.5; i represents the i-th BeiDou satellite (calculated by traversing all currently visible satellites), i = 1, 2, ..., n; n represents the total number of BeiDou satellites currently received by the base station, where n is an integer; C / N0 (i) E represents the carrier-to-noise ratio of the i-th satellite, reflecting the ratio of signal strength to noise, measured in dB-Hz; l (i) The elevation angle of the i-th satellite is its angle of elevation relative to the horizontal plane of the reference station, ranging from 0° to 90° in radians; sin(E l (i) ) represents the sine weighting of the satellite elevation angle, used to suppress interference from low-elevation satellites (low-elevation satellites are susceptible to multipath effects), ranging from 0 to 1;

[0030] Deformation early warning pipeline:

[0031] Using GNSS observation data from multiple reference stations, differential positioning technology is used to calculate the relative position changes (baseline vectors) between stations, and initial data of millimeter-level deformation is obtained for baseline calculation.

[0032] A state-space model is established, and noise and real deformation signals are separated by a prediction-update cycle to achieve Kalman filtering for noise reduction.

[0033] The data is decomposed into different frequency bands using the Daubechies wavelet basis, retaining only the low-frequency components and eliminating non-geological disaster signals, thus completing the wavelet transform to extract the trend.

[0034] Thresholds are set: static thresholds are based on the historical maximum safe deformation, while dynamic thresholds are adjusted in conjunction with external factors; triggering mechanisms are set: Level 1 warning (yellow) is triggered when the deformation rate exceeds the threshold by 50%, and manual review is initiated; Level 2 warning (orange) is triggered when the deformation rate continues to exceed the threshold and the acceleration is >0.1mm / day2, and the data is automatically pushed to the monitoring platform; Level 3 warning (red) is triggered when the deformation reaches the critical value, and BeiDou RDSS broadcast and SMS multi-channel warnings are triggered.

[0035] Furthermore, the distribution of base stations for the BeiDou positioning system in this plateau region includes the following steps:

[0036] (1) Laying out a global reference network: One reference station is set up every 50-80km along the main axis of the river. Priority is given to areas with open terrain and stable geology. The station is built according to the Class B Beidou reference station standard, equipped with multi-frequency Beidou receivers (B1C / B2a / B3I), meteorological sensors and atomic clocks. It is connected with the Beidou ground-based augmentation system to achieve a unified coordinate framework. Data is transmitted back through satellite communication to ensure coverage of uninhabited areas. The national coordinate reference is introduced to constrain the overall adjustment and provide a basin-level location reference.

[0037] (2) Laying out regional enhancement networks: In manned sections, one base station is deployed every 5-20km. Around the engineering hub, a triangular or quadrilateral network is constructed with a single station coverage radius of ≤10km. Every 3 stations form a synchronous observation unit, and local accuracy is improved through short baseline joint calculation. In uninhabited sections, one base station is deployed every 10-25km along both banks of the river, with a horizontal interval of ≥3km between the left and right banks and a vertical height difference of ≤500m. Each base station forms cross coverage with two adjacent stations on the opposite bank to eliminate signal blind spots on one bank. In special terrain sections such as sharp bends and canyon entrances, the base station density is increased, the distance between base stations is shortened to 8-15km, and a terrain reflection signal compensation algorithm is added.

[0038] In summary, this application includes at least one of the following beneficial technical effects:

[0039] The system of this invention is divided into a hardware layer, a data layer, and a service layer. This layered structure facilitates modular design and improves the system's maintainability and scalability. The time synchronization module in the base station equipment uses a BeiDou / GPS dual-mode atomic clock to ensure high-precision time synchronization, which is crucial for navigation and positioning. The environmental monitoring unit monitors the stability of the foundation, preventing equipment failure due to geological changes and improving reliability. The remote control interface supports protocols with high protection levels, adapting to harsh high-altitude environments.

[0040] The user terminal's multi-mode communication module automatically selects the optimal link to ensure communication remains stable even in high-altitude areas with unstable signals. The data fusion unit employs an extended Kalman filter to fuse multiple positioning data sources, improving positioning accuracy and robustness.

[0041] The communication network employs different transmission protocols for different areas (uninhabited and inhabited areas), ensuring both data transmission reliability in uninhabited areas and data security in inhabited areas. The data processing center utilizes distributed computing and hierarchical storage, improving data processing efficiency and storage economy.

[0042] The location service mode combines a hybrid location engine and QoS tiered services to meet both real-time and post-event location needs, while prioritizing critical applications such as geological disaster monitoring. The anomaly monitoring mode utilizes health assessment and deformation early warning pipelines to achieve early warnings and reduce disaster risks.

[0043] Regarding base station distribution methods, the combination of a global reference network and regional enhancement networks ensures coverage and accuracy. Deploying base stations along the main river axis and intensifying deployment in challenging terrain addresses signal blind spots caused by complex topography. Alternating deployment and cross-coverage design further enhance signal reliability. Coordinate framework unification with national coordinate benchmarks ensures data consistency. This provides highly reliable technical support for the safety management of plateau waters. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of the three-layer collaborative relationship of a navigation and positioning system for plateau waters according to an embodiment of the present invention. Detailed Implementation

[0045] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0046] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0047] According to one embodiment of the present invention, such as Figure 1 As shown, a navigation and positioning system for plateau waters includes a hardware layer, a data layer, and a service layer. The hardware layer, data layer, and service layer coordinate with each other through a multi-level data flow and control mechanism.

[0048] Hardware layer: multi-source data acquisition, data sensing and physical support, including base station equipment and user terminals;

[0049] The base station equipment includes:

[0050] Time synchronization module: Built-in BeiDou / GPS dual-mode atomic clock, achieving network-wide time synchronization through BeiDou satellite signals;

[0051] Environmental monitoring unit: integrates soil moisture sensor and inclinometer to monitor the foundation stability of the base station equipment in real time;

[0052] Remote control interface: Supports RS485 / Modbus protocol with IP67 protection rating, used to adjust antenna elevation angle and transmit power;

[0053] User terminals include:

[0054] Multi-mode communication module: Supports 4G / BeiDou RDSS / LoRa three-mode switching, and automatically selects the optimal link based on signal strength;

[0055] Data fusion unit: Employs an extended Kalman filter (EKF) to fuse BeiDou RTK, barometric altimeter, and inertial navigation data.

[0056] The base station connects to the BeiDou receiver and weather instrument via an RS232 interface, and the data is uploaded to the data center via a 4G module or a BeiDou short message terminal. User terminals network with nearby base stations via LoRa modules to form a "star topology," with the central node responsible for data aggregation and relay.

[0057] Data layer: Information transmission and intelligent processing, including communication networks and data processing centers;

[0058] The communication network includes:

[0059] Transmission protocols in uninhabited areas: BeiDou short messages use BDS-3RDSS enhanced messages and transmit raw observations through data fragmentation and compression technology; LoRa self-organizing networks use TDMA time division multiple access protocol, setting fixed time slots of 10 minutes / time to reduce the probability of collisions;

[0060] Manned area transmission protocol: based on the RTCM3.3 standard, the observation data is encapsulated and encrypted through NTRIP over HTTPS.

[0061] The data processing center includes:

[0062] Distributed computing cluster: Adopting a Hadoop+Spark architecture, the master node is responsible for PPP-RTK computation, and the slave nodes process ionospheric modeling in parallel.

[0063] Data storage solution: Cold and hot data are stored in a tiered manner, real-time data is stored in a Redis database, and historical data is archived to MinIO object storage.

[0064] Base station data is transmitted directly to the data center via a dedicated fiber optic line or VPN tunnel, with a 4G link serving as a backup channel. LoRa self-organizing network data is converted to TCP / IP protocol via an edge gateway (built-in Rockchip RK3399) before being uploaded.

[0065] Service layer: Scenario-based applications and decision support, including location service mode and anomaly monitoring mode.

[0066] Location service models include:

[0067] Hybrid positioning engine: Real-time differential positioning generates VRS virtual observations and reduces bandwidth usage through Extended Predicted Orbit (EPO) technology; Post-event precise positioning provides a RINEX 3.04 format download interface and supports online solution platforms, including at least one of CSRS-PPP and GAPS.

[0068] Resources are dynamically allocated based on user permissions, prioritizing the data throughput of geological disaster monitoring terminals.

[0069] Regular monitoring modes include:

[0070] Baseline station health assessment: Design an SNR (signal-to-noise ratio) index model, the specific formula is as follows:

[0071]

[0072] Wherein, SNRscore represents the comprehensive score index of the base station's signal quality; the smaller the value, the worse the signal. An alarm is triggered when SNRscore < 2.5; i represents the i-th BeiDou satellite (calculated by traversing all currently visible satellites), i = 1, 2, ..., n; n represents the total number of BeiDou satellites currently received by the base station, where n is an integer; C / N0 (i) E represents the carrier-to-noise ratio of the i-th satellite, reflecting the ratio of signal strength to noise, measured in dB-Hz; l (i) The elevation angle of the i-th satellite is its angle of elevation relative to the horizontal plane of the reference station, ranging from 0° to 90° in radians; sin(E l (i) ) represents the sine weighting of the satellite elevation angle, used to suppress interference from low-elevation satellites (low-elevation satellites are susceptible to multipath effects), ranging from 0 to 1;

[0073] Deformation early warning pipeline:

[0074] Using GNSS observation data from multiple reference stations, differential positioning technology is used to calculate the relative position changes (baseline vectors) between stations, and initial data of millimeter-level deformation is obtained for baseline calculation.

[0075] A state-space model is established, and noise and real deformation signals are separated by a prediction-update cycle to achieve Kalman filtering for noise reduction.

[0076] The data is decomposed into different frequency bands using the Daubechies wavelet basis, retaining only the low-frequency components and eliminating non-geological disaster signals, thus completing the wavelet transform to extract the trend.

[0077] Thresholds are set: static thresholds are based on the historical maximum safe deformation, while dynamic thresholds are adjusted in conjunction with external factors; triggering mechanisms are set: Level 1 warning (yellow) is triggered when the deformation rate exceeds the threshold by 50%, and manual review is initiated; Level 2 warning (orange) is triggered when the deformation rate continues to exceed the threshold and the acceleration is >0.1mm / day2, and the data is automatically pushed to the monitoring platform; Level 3 warning (red) is triggered when the deformation reaches the critical value, and BeiDou RDSS broadcast and SMS multi-channel warnings are triggered.

[0078] User terminals subscribe to data center topics via the MQTT protocol to receive differential correction data and early warning information in real time. Geological disaster monitoring data is connected to the government's emergency management platform via an HTTP REST API.

[0079] This invention also discloses the base station distribution method of the BeiDou positioning system in the plateau region, including the following steps:

[0080] (1) Laying out a global reference network: One reference station is set up every 50-80km along the main axis of the river. Priority is given to areas with open terrain and stable geology. The station is built according to the Class B Beidou reference station standard, equipped with multi-frequency Beidou receivers (B1C / B2a / B3I), meteorological sensors and atomic clocks. It is connected with the Beidou ground-based augmentation system to achieve a unified coordinate framework. Data is transmitted back through satellite communication to ensure coverage of uninhabited areas. The national coordinate reference is introduced to constrain the overall adjustment and provide a basin-level location reference.

[0081] (2) Laying out regional enhancement networks: In manned sections, one base station is deployed every 5-20km, and a triangular or quadrilateral network is constructed around the engineering hub, with a single station coverage radius of ≤10km. Every 3 stations form a synchronous observation unit, and local accuracy is improved through short baseline joint calculation. In uninhabited sections, one base station is deployed every 10-25km, with alternating deployment along both banks of the river, with a horizontal interval of ≥3km between the left and right banks and a vertical height difference of ≤500m. Each base station forms cross coverage with two adjacent stations on the opposite bank to eliminate signal blind spots on one bank. In special terrain sections such as sharp bends and canyon entrances, the base station deployment is densified, the spacing between base stations is shortened to 8-15km, and a terrain reflection signal compensation algorithm is added.

[0082] This invention discloses a navigation and positioning system for high-altitude waters, divided into a hardware layer, a data layer, and a service layer. This layered structure facilitates modular design and improves system maintainability and scalability. The time synchronization module in the base station equipment uses a BeiDou / GPS dual-mode atomic clock, ensuring high-precision time synchronization, which is crucial for navigation and positioning. The environmental monitoring unit monitors ground stability, preventing equipment failure due to geological changes and improving reliability. The remote control interface supports protocols with high protection levels, adapting to the harsh environment of high-altitude areas.

[0083] The user terminal's multi-mode communication module automatically selects the optimal link to ensure communication remains stable even in high-altitude areas with unstable signals. The data fusion unit employs an extended Kalman filter to fuse multiple positioning data sources, improving positioning accuracy and robustness.

[0084] The communication network employs different transmission protocols for different areas (uninhabited and inhabited areas), ensuring both data transmission reliability in uninhabited areas and data security in inhabited areas. The data processing center utilizes distributed computing and hierarchical storage, improving data processing efficiency and storage economy.

[0085] The location service mode combines a hybrid location engine and QoS tiered services to meet both real-time and post-event location needs, while prioritizing critical applications such as geological disaster monitoring. The anomaly monitoring mode utilizes health assessment and deformation early warning pipelines to achieve early warnings and reduce disaster risks.

[0086] Regarding base station distribution methods, the combination of a global reference network and regional enhancement networks ensures coverage and accuracy. Deploying base stations along the main river axis and intensifying deployment in challenging terrain addresses signal blind spots caused by complex topography. Alternating deployment and cross-coverage design further enhance signal reliability. Coordinate framework unification with national coordinate benchmarks ensures data consistency. This provides highly reliable technical support for the safety management of plateau waters.

[0087] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A navigation and positioning system for high-altitude waters, characterized in that, include: Hardware layer: multi-source data acquisition, data sensing and physical support, including base station equipment and user terminals; Data layer: Information transmission and intelligent processing, including communication networks and data processing centers; Service layer: Scenario-based applications and decision support, including location service mode and anomaly monitoring mode; The hardware layer, the data layer, and the service layer collaborate through a multi-level data flow and control mechanism.

2. A navigation and positioning system for plateau waters according to claim 1, characterized in that, The base station equipment includes: Time synchronization module: Built-in BeiDou / GPS dual-mode atomic clock, achieving network-wide time synchronization through BeiDou satellite signals; Environmental monitoring unit: integrates soil moisture sensor and inclinometer to monitor the foundation stability of the base station equipment in real time; Remote control interface: Supports RS485 / Modbus protocol with IP67 protection rating, used to adjust antenna elevation angle and transmit power.

3. A navigation and positioning system for plateau waters according to claim 1, characterized in that, The user terminal includes: Multi-mode communication module: Supports 4G / BeiDou RDSS / LoRa three-mode switching, and automatically selects the optimal link based on signal strength; Data fusion unit: Employs an extended Kalman filter (EKF) to fuse BeiDou RTK, barometric altimeter, and inertial navigation data.

4. A navigation and positioning system for plateau waters according to claim 1, characterized in that, The communication network includes: Transmission protocols in uninhabited areas: BeiDou short messages use BDS-3RDSS enhanced messages, transmitting raw observations through data fragmentation and compression technology; LoRa self-organizing networks use TDMA time division multiple access protocol, setting fixed time slots of 10 minutes / time to reduce the probability of collisions; Manned area transmission protocol: based on the RTCM3.3 standard, the observation data is encapsulated and encrypted through NTRIP over HTTPS.

5. A navigation and positioning system for plateau waters according to claim 1, characterized in that, The data processing center includes: Distributed computing cluster: Adopting a Hadoop+Spark architecture, the master node is responsible for PPP-RTK computation, and the slave nodes process ionospheric modeling in parallel; Data storage solution: Cold and hot data are stored in a tiered manner, real-time data is stored in a Redis database, and historical data is archived to MinIO object storage.

6. A navigation and positioning system for plateau waters according to claim 3, characterized in that, The location service modes include: Hybrid positioning engine: Real-time differential positioning generates VRS virtual observations and reduces bandwidth usage through Extended Predicted Orbit (EPO) technology; Post-event precise positioning provides a RINEX 3.04 format download interface and supports an online solution platform, which includes at least one of CSRS-PPP and GAPS. QoS Tiered Service: Resources are dynamically allocated based on user permissions, prioritizing the data throughput of geological disaster monitoring terminals.

7. A navigation and positioning system for plateau waters according to claim 1, characterized in that, The anomaly monitoring modes include: Baseline station health assessment: Design an SNR (signal-to-noise ratio) index model, the specific formula is as follows: Wherein, SNRscore represents the comprehensive score index of the base station's signal quality; the smaller the value, the worse the signal. An alarm is triggered when SNRscore < 2.5; i represents the i-th BeiDou satellite (calculated by traversing all currently visible satellites), i = 1, 2, ..., n; n represents the total number of BeiDou satellites currently received by the base station, where n is an integer; C / N0 (i) E represents the carrier-to-noise ratio of the i-th satellite, reflecting the ratio of signal strength to noise, measured in dB-Hz; l (i) The elevation angle of the i-th satellite is its angle of elevation relative to the horizontal plane of the reference station, ranging from 0° to 90° in radians; sin(E l (i) ) represents the sine weighting of the satellite elevation angle, used to suppress interference from low-elevation satellites (low-elevation satellites are susceptible to multipath effects), ranging from 0 to 1; Deformation early warning pipeline: Using GNSS observation data from multiple reference stations, differential positioning technology is used to calculate the relative position changes (baseline vectors) between stations, and initial data of millimeter-level deformation is obtained for baseline calculation. A state-space model is established, and noise and real deformation signals are separated by a prediction-update cycle to achieve Kalman filtering for noise reduction. The data is decomposed into different frequency bands using the Daubechies wavelet basis, retaining only the low-frequency components and eliminating non-geological disaster signals, thus completing the wavelet transform to extract the trend. Thresholds are set: static thresholds are based on the historical maximum safe deformation, while dynamic thresholds are adjusted in conjunction with external factors; triggering mechanisms are set: Level 1 warning (yellow) is triggered when the deformation rate exceeds the threshold by 50%, and manual review is initiated; Level 2 warning (orange) is triggered when the deformation rate continues to exceed the threshold and the acceleration is >0.1mm / day2, and the data is automatically pushed to the monitoring platform; Level 3 warning (red) is triggered when the deformation reaches the critical value, and BeiDou RDSS broadcast and SMS multi-channel warnings are triggered.

8. A navigation and positioning system for plateau waters as described in any one of 1-7, providing a base station distribution method for the BeiDou positioning system in the plateau region, characterized in that, Includes the following steps: (1) Laying out a global reference network: One reference station is set up every 50-80km along the main axis of the river. Priority is given to areas with open terrain and stable geology. The station is built according to the Class B Beidou reference station standard, equipped with multi-frequency Beidou receivers (B1C / B2a / B3I), meteorological sensors and atomic clocks. It is connected with the Beidou ground-based augmentation system to achieve a unified coordinate framework. Data is transmitted back through satellite communication to ensure coverage of uninhabited areas. The national coordinate reference is introduced to constrain the overall adjustment and provide a basin-level location reference. (2) Laying out regional enhancement networks: In manned sections, one base station is deployed every 5-20km. Around the engineering hub, a triangular or quadrilateral network is constructed with a single station coverage radius of ≤10km. Every 3 stations form a synchronous observation unit, and local accuracy is improved through short baseline joint calculation. In uninhabited sections, one base station is deployed every 10-25km along both banks of the river, with a horizontal interval of ≥3km between the left and right banks and a vertical height difference of ≤500m. Each base station forms cross coverage with two adjacent stations on the opposite bank to eliminate signal blind spots on one bank. In special terrain sections such as sharp bends and canyon entrances, the base station density is increased, the distance between base stations is shortened to 8-15km, and a terrain reflection signal compensation algorithm is added.

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