I. Requirements Analysis

Geological hazards such as landslides and subsidence caused by underground mining activities lead to surface deformation. These surface deformations directly impact the foundations, towers, and spans of high-voltage transmission line towers, further inducing deformation in other components of the transmission lines. Collapses and failures occur frequently, posing severe threats to grid safety. Therefore, it is necessary to establish an online monitoring system for Beidou tower settlement along transmission lines. This system enables real-time tracking of inclination and settlement at each tower, comprehensively enhancing the management level of transmission line towers.

II. Working Principle

The online settlement monitoring device for Beidou transmission tower poles employs millimeter-level or centimeter-level Beidou high-precision relative positioning technology. Relative positioning involves placing two (or more) receivers at opposite ends of one (or multiple) baselines to simultaneously observe the same Beidou satellites, thereby determining the relative positions of baseline endpoints or baseline vectors. During relative positioning, differential calculations eliminate satellite clock errors, receiver clock errors, and mitigate the effects of ionospheric and tropospheric refraction while resolving integer ambiguity parameters. This enhances baseline accuracy. By deploying BeiDou monitoring antennas on towers requiring positioning and integrating data from national BeiDou ground-based augmentation stations, the system transmits carrier phase data, ephemeris, and other required parameters to the data center via an encrypted communication network. ephemeris data to the data center via encrypted communication networks. The data center receives raw real-time data streams from each monitoring point and base station. Utilizing the BeiDou data processing engine, it performs baseline calculations between base stations and positioning points to obtain high-precision real-time 3D coordinates of the tower, thereby monitoring its settlement.

III. Features and Functions

1. Basic Configuration for BeiDou Tower Settlement Monitoring: Master Control Unit, BeiDou Settlement Monitoring Unit, Communication Unit, Power Supply Unit, BeiDou Communication Module, Mounting Bracket, and Auxiliary Materials;

2. Collect high-precision real-time 3D coordinates, base station observation data, monitoring point observation data, as well as ephemeris and precise ephemeris data. Transmit encrypted data via 4G/5G signals to the service platform for processing, then analyze the data using BeiDou ground-based augmentation network resources.

3. BeiDou Receiver Functionality: Includes all equipment encompassing data acquisition, centralized transmission, processing and calculation, display and recording, as well as safety protection facilities such as lightning protection and anti-theft measures. This enables the transmission of monitoring data to the monitoring center for display.

4. Unattended Monitoring System: Annual operational reliability exceeds 99%, ensuring 24/7 continuous reliable operation with over 100,000 hours of uninterrupted fault-free runtime.

5. Real-time display and analysis of deformation data, enabling intermittent health status assessments;

6. Central software automatic calculation: The shortest response time ranges from minutes to hours, with real-time network adjustment and automatic evaluation of monitoring results. All parameters are fully configurable by users according to specific monitoring requirements.

7. Diverse daily channel alerts: Alerts are delivered via web, app notifications, and SMS messages, ensuring you stay informed about power tower deformation status anytime, anywhere.

8. Continuously monitor the spatial displacement of deformation points on power transmission towers to determine the deformation status and geometric alignment of the affected zones.

9. Provides high-quality dual-frequency BeiDou measurement data, delivering real-time millimeter-level positioning accuracy. Static accuracy specifications: Horizontal: <±2mm +0.5ppm; Vertical: <±4mm +0.5ppm. Real-time monitoring accuracy during wind-induced vibration of power transmission towers: Horizontal: <±10mm; Vertical: <±20mm.

10. Automatically generate reports with customizable reporting cycles (e.g., weekly, daily). Users can freely add or remove essential output information. Additionally, weekly or monthly trend curves for specific data points can be automatically generated as needed.

11. The system employs a modular design with standardized, integrated components to facilitate on-site installation and maintenance.

IV. Product Specifications

Serial Number	Category	Project Name	Technical Specifications
1	Overall Performance	Complete System Configuration	Master Control Unit, Beidou Settlement Monitoring Unit, Communication Unit, Power Supply Unit, Mounting Bracket, and Auxiliary Materials
		Overall quality	Less than 40 kg (including solar panels and mounting brackets)
		Material	Stainless steel body + hot-dip galvanized bracket
2	Beidou Settlement Monitoring Unit	Observation frequency	Receives signals from multiple navigation satellite systems: BDS (B1/B2), GPS (L1/L2)
		Measurement Accuracy	Horizontal accuracy: ±2.5 mm + 0.5 ppm; Vertical accuracy: ±5 mm + 0.5 ppm
		Signal Reception Sensitivity	Less than or equal to -133 dBm
		Power Supply	Power Input Port
		Antenna	1 GNSS antenna interface, socket type TNC
		Remote Control	Supports remote upgrades, remote reset, and remote parameter configuration.
		Number of BeiDou modules	Supports up to 4
3	Beidou Antenna Unit	Signal Tracking	Capable of receiving GPS satellite signals L1, L2, L5; GLONASS satellite signals L1, L2; BeiDou satellite signals B1, B2, B3; and Galileo satellite signals.
		Phase Center Indicator	A set of communication interface outputs, available in RS232 (default) or TTL level configurations.
		Antenna Beam	Azimuth: 0° to 360°, Elevation: 5° to 90°
		Axle ratio	2 dB (elevation angle 90°) ≤ 4 dB (elevation angle 20°–90°)
		Voltage Standing Wave Ratio	≤1.5 (50Ω)
4	Communication Unit	Communication method	All-network 4G/5G/WiFi/Beidou communication module/wireless transmission
		Data Security	Communication with the main site can utilize a dedicated VPN channel, with optional encrypted transmission.
		Access Protocol	Compatible with monitoring platforms of provincial power companies such as China Southern Power Grid and State Grid
5	Power Supply Unit	Battery capacity	100Ah/12V, Lithium Iron Phosphate Battery High Reliability Battery
		Solar Panel Power Rating	180W/18V, Monocrystalline Silicon High-Efficiency Solar Panel
		Power supply duration	The device can maintain normal operation for 15 days without external power supply.
6	Other parameters	Overall service life	Over 8 years
		Protection Rating	IP66