BOTDR (Brillouin Optical Time Domain Reflectometer)-based aerial optical cable environment sensing and state monitoring system

Abstract

The invention discloses an aerial optical cable environment sensing and state monitoring system based on a BOTDR (Brillouin Optical Time Domain Reflectometer), and relates to the technical field of optical cable monitoring. The system comprises a BOTDR (Brillouin Optical Time Domain Reflectometer) detection module, a distributed sensing optical cable, an environment sensing module, a data processing module and an early warning and display module, the distributed sensing optical cable is closely attached to the aerial optical cable in parallel to sense strain and temperature information; the BOTDR detection module obtains original data through a Brillouin scattering effect; the environment sensing module collects environment parameters such as temperature, humidity and wind speed at key nodes; the data processing module carries out calibration and fusion analysis on the multi-source data, and outputs a state evaluation result by means of a random forest algorithm model; the early warning and display module is used for realizing graded early warning and data visualization; the system further comprises a data storage module combining cloud storage and local storage, the problems that in the prior art, the monitoring dimension is single, and the evaluation accuracy is insufficient are solved, fault reasons can be accurately distinguished, the system adapts to the outdoor complex environment, and it is guaranteed that a communication network is stable and reliable.

Description

Technical Field

[0001] This invention relates to the field of optical cable monitoring technology, specifically to an overhead optical cable environmental sensing and status monitoring system based on BOTDR. Background Technology

[0002] Aerial optical cables, as a crucial component of communication networks, are widely used in long-distance communications, metropolitan area networks, and access networks. Because aerial optical cables are exposed to the outdoor environment for extended periods, they are susceptible to factors such as temperature variations, wind, icing, lightning strikes, vibration, and human-caused damage. This can lead to excessive strain, increased losses, and even breakage, severely impacting the stability and reliability of communication networks. Therefore, achieving real-time, accurate status monitoring and environmental awareness of aerial optical cables, enabling timely detection and early warning of potential faults, is of paramount importance for ensuring the security of communication networks.

[0003] Currently, overhead optical cable monitoring technologies mainly include manual inspection, fiber optic time domain reflectometry (OTDR) technology, and fiber optic grating (FBG) sensing technology. Manual inspection is inefficient, costly, and difficult to achieve all-weather, full-coverage monitoring; OTDR technology is mainly used to detect optical cable breaks and cannot achieve distributed monitoring of optical cable condition parameters such as strain and temperature; although FBG sensing technology can achieve fixed-point monitoring, the number of monitoring points is limited and it is susceptible to external interference, making it difficult to meet the monitoring needs of long-distance, large-area overhead optical cables. Summary of the Invention

[0004] This invention aims to provide a BOTDR-based environmental perception and condition monitoring system for overhead optical cables. It primarily addresses the problems of limited monitoring dimensions and insufficient accuracy in condition assessment inherent in existing BOTDR-based optical cable monitoring systems. This invention improves the accuracy of condition assessment and the reliability of early warning by integrating the optical cable's own strain, temperature parameters, and environmental parameters for comprehensive analysis.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: An overhead optical cable environmental perception and status monitoring system based on BOTDR includes a Brillouin optical time domain reflectometer (BOTDR) detection module, a distributed sensing optical cable, an environmental perception module, a data processing module, and an early warning and display module.

[0006] Distributed sensing optical cables are laid in parallel and closely fitted with overhead optical cables. Their function is to sense the strain and temperature information of both themselves and the overhead optical cables. Because the distributed sensing optical cables and the overhead optical cables are closely fitted, they experience the same environmental changes and mechanical forces simultaneously. Therefore, the strain and temperature information sensed by the distributed sensing optical cables accurately reflects the strain and temperature status of the overhead optical cables. To improve the weather resistance and service life of the distributed sensing optical cables, they use armored single-mode optical fibers with an outer weather-resistant protective layer of polytetrafluoroethylene (PTFE), effectively resisting the corrosion of harsh outdoor environments.

[0007] The Brillouin Optical Time Domain Reflectometer (BOTDR) detection module connects to a distributed sensing optical cable. Its core function is to emit pulsed laser light into the cable and receive the Brillouin scattered light signal returned after scattering by the cable. This signal is then preliminarily processed to obtain raw strain and temperature data. The BOTDR module's pulsed laser repetition frequency is set to 1kHz-10kHz, with a Brillouin frequency shift measurement accuracy of at least ±1MHz and a spatial resolution of at least 1m, enabling high-precision, distributed monitoring of long-distance overhead optical cables. Specifically, the BOTDR module includes a pulsed laser generator, an optical coupler, a photodetector, and a signal preprocessing unit: the pulsed laser generator produces a narrow-pulse laser signal; the optical coupler couples the narrow-pulse laser signal to the distributed sensing optical cable and couples the returned Brillouin scattered light signal to the photodetector; the photodetector converts the optical signal into an electrical signal; and the signal preprocessing unit amplifies, filters, and performs analog-to-digital conversion on the electrical signal to obtain raw strain and temperature data suitable for further processing.

[0008] The environmental sensing module is installed at key nodes of the overhead optical cable, such as cable junction boxes, midpoints of the span, and areas susceptible to environmental influences, to collect environmental parameters of the environment in which the cable is located. The module includes temperature and humidity sensors, wind speed sensors, light intensity sensors, and vibration sensors, which collect data on ambient temperature and humidity, wind speed, light intensity, and cable vibration, respectively, enabling multi-dimensional sensing of the cable's environment. To adapt to outdoor scenarios without mains power, each sensor employs a low-power design, powered by a combination of solar panels and lithium batteries, and supports LoRa wireless communication for data transmission with the data processing module, combining the advantages of low power consumption and long-distance communication.

[0009] The data processing module is connected to the Brillouin optical time domain reflectometer (BOTDR) detection module and the environmental sensing module, respectively. It is the core processing unit of the system and is used to fuse and analyze the raw strain data, raw temperature data and environmental parameters to obtain the status assessment results of the overhead optical cable. The data processing module includes a data receiving unit, a data calibration unit, a fusion analysis unit, and a state assessment unit. The data receiving unit synchronously receives raw data transmitted from the BOTDR detection module and environmental parameters transmitted from the environmental sensing module. The data calibration unit performs temperature compensation calibration on the raw strain data based on temperature and humidity data from the environmental parameters, eliminating the interference of temperature changes on the optical cable strain measurement results and obtaining calibrated strain data. The fusion analysis unit performs feature fusion on the calibrated strain data, raw temperature data, and wind speed and vibration data from the environmental parameters, extracting an optical cable state feature vector that includes the optical cable's own state and environmental influences. The state assessment unit inputs the optical cable state feature vector into a preset state assessment model to obtain the state assessment results of the overhead optical cable. The state assessment results are divided into four levels: normal, slightly abnormal, moderately abnormal, and severely abnormal. The preset state assessment model is a model built based on the random forest algorithm, trained using a large amount of historical monitoring data and corresponding actual optical cable state labels, and has high assessment accuracy.

[0010] The early warning and display module is connected to the data processing module and is used to issue early warning prompts based on the status assessment results, and to intuitively display relevant monitoring data and assessment results. The early warning and display module includes an early warning unit and a display unit: the early warning unit triggers different levels of early warning based on the status assessment results, with a yellow warning for minor anomalies, an orange warning for moderate anomalies, and a red warning for severe anomalies. The early warning method combines audible and visual warnings with SMS push notifications to ensure that relevant personnel can obtain early warning information in a timely manner; the display unit uses a touch screen to display the spatial distribution of the distributed sensing optical cable, strain values, temperature values, environmental parameters, and status assessment results at each monitoring point in real time, allowing personnel to intuitively grasp the operating status of the optical cable.

[0011] In addition, the system also includes a data storage module, which is connected to the data processing module and is used to store raw monitoring data, calibrated data, status assessment results and historical early warning information. The data storage module adopts a combination of cloud storage and local storage, which not only ensures the safe backup of data, but also makes it easy for staff to retrieve historical data for analysis at any time.

[0012] Working principle and beneficial effects of the present invention: 1. Working Principle: Distributed sensing optical cables and overhead optical cables synchronously sense environmental changes and mechanical forces, generating strain and temperature responses. The BOTDR detection module uses the Brillouin scattering effect to convert the strain and temperature responses of the optical cable into raw data. The environmental sensing module collects surrounding environmental parameters at key nodes, supplementing environmental dimension data. The data processing module integrates the three types of raw data, eliminates interference, analyzes the true state, and outputs evaluation results. The early warning and display module triggers early warnings based on the evaluation results and visualizes the data to support operation and maintenance decisions. It should be further explained that by using distributed sensing optical cables to achieve long-distance, full-coverage monitoring of the optical cable's own status, supplementing the environmental dimension with an environmental perception module, and then using data processing module for fusion analysis, the problem of inaccurate assessment caused by existing technologies that "only monitor the optical cable's own parameters and ignore environmental influences" can be solved, ultimately achieving the core goal of "accurate monitoring and reliable early warning".

[0013] 2. Beneficial effects: (1) The present invention realizes distributed monitoring of strain and temperature of overhead optical cable through BOTDR detection module, and collects parameters such as temperature, humidity, wind speed and vibration of the environment where the optical cable is located through environmental sensing module. It integrates the optical cable's own state parameters and environmental parameters for comprehensive analysis, effectively solving the problem of single monitoring dimension of the existing system and improving the accuracy of state assessment. (2) The present invention sets up a data calibration unit to perform temperature compensation calibration on the original strain data, which eliminates the interference of temperature change on the strain measurement results. At the same time, it adopts a state assessment model based on random forest algorithm, and performs state assessment by fusing multi-dimensional data, which can effectively distinguish the causes of optical cable strain and improve the reliability of state assessment results.

[0014] (3) The present invention sets up a multi-level early warning mechanism based on the status assessment results, and adopts an early warning method that combines sound and light warning with SMS push to ensure that staff can obtain optical cable abnormal information in a timely manner. At the same time, the monitoring data and assessment results are displayed intuitively through the touch screen, which makes it easy for staff to quickly locate the abnormal location and take handling measures.

[0015] (4) The present invention adopts a weather-resistant protective layer design for distributed sensing optical cables and low power consumption, solar power supply and LoRa wireless communication for environmental sensing modules, so that the system can adapt to the complex power supply and communication environment outdoors, thereby improving the practicality and stability of the system.

[0016] Preferably, the BOTDR detection module includes a pulsed laser generator, an optical coupler, a photodetector, and a signal preprocessing unit; the pulsed laser generator is used to generate a narrow pulsed laser signal; the optical coupler is used to couple the narrow pulsed laser signal to a distributed sensing optical cable and to couple the Brillouin scattering light signal returned from the distributed sensing optical cable to the photodetector; the photodetector is used to convert the Brillouin scattering light signal into an electrical signal; the signal preprocessing unit is used to amplify, filter, and perform analog-to-digital conversion on the electrical signal to obtain raw strain data and raw temperature data.

[0017] Preferably, the environmental sensing module includes a temperature and humidity sensor, a wind speed sensor, a light sensor, and a vibration sensor; the temperature and humidity sensor is used to collect environmental temperature and humidity data; the wind speed sensor is used to collect environmental wind speed data; the light sensor is used to collect environmental light intensity data; and the vibration sensor is used to collect vibration data of the overhead optical cable.

[0018] Preferably, the data processing module includes a data receiving unit, a data calibration unit, a fusion analysis unit, and a state assessment unit; the data receiving unit is used to receive raw strain data, raw temperature data, and environmental parameters; the data calibration unit is used to perform temperature compensation calibration on the raw strain data based on the temperature and humidity data in the environmental parameters to obtain calibrated strain data; the fusion analysis unit is used to perform feature fusion on the calibrated strain data, raw temperature data, and wind speed and vibration data in the environmental parameters to extract the optical cable state feature vector; the state assessment unit is used to input the optical cable state feature vector into a preset state assessment model to obtain the state assessment result of the overhead optical cable, the state assessment result including normal, slightly abnormal, moderately abnormal, and severely abnormal.

[0019] Preferably, the preset state assessment model is a model built based on the random forest algorithm. The model is trained using historical monitoring data and corresponding optical cable actual state labels. The historical monitoring data includes historical strain data, historical temperature data, and historical environmental parameters.

[0020] Preferably, the early warning and display module includes an early warning unit and a display unit; the early warning unit triggers different levels of early warning based on the status assessment results, with a yellow warning for mild anomalies, an orange warning for moderate anomalies, and a red warning for severe anomalies, and the early warning methods include audible and visual warnings and SMS push notifications; the display unit uses a touch screen to display in real time the spatial distribution of the distributed sensing optical cable, the strain value, temperature value, environmental parameters, and status assessment results of each monitoring point.

[0021] Preferably, the distributed sensing optical cable uses armored single-mode optical fiber, and the outer layer of the armored single-mode optical fiber is provided with a weather-resistant protective layer, the material of which is polytetrafluoroethylene.

[0022] Preferably, the system also includes a data storage module, which is connected to the data processing module and is used to store raw monitoring data, calibrated data, status assessment results, and historical early warning information. The data storage module adopts a combination of cloud storage and local storage.

[0023] Preferably, the pulsed laser repetition frequency of the BOTDR detection module is 1kHz-10kHz, the Brillouin frequency shift measurement accuracy is not less than ±1MHz, and the spatial resolution is not less than 1m.

[0024] Preferably, each sensor in the environmental sensing module adopts a low-power design, is powered by a combination of solar panels and lithium batteries, and supports LoRa wireless communication for data transmission with the data processing module.

[0025] Attached image description: Figure 1 This is a structural block diagram of the BOTDR-based overhead optical cable environmental sensing and status monitoring system described in an embodiment of the present invention. Figure 2 This is a structural block diagram of the BOTDR detection module described in an embodiment of the present invention; Figure 3 This is a structural block diagram of the data processing module described in an embodiment of the present invention; Figure 4 This is a structural block diagram of the early warning and display module described in an embodiment of the present invention. Detailed Implementation

[0026] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0027] In this disclosure, unless otherwise stated, directional terms such as "upper," "lower," "front," "rear," "left," and "right" are used for ease of description based on the drawing orientations of the corresponding figures, while "inner" and "outer" are defined based on the contours of the corresponding components themselves. Terms such as "first" and "second" used in this disclosure are used to distinguish one element from another and do not have sequential or importance implications. Furthermore, when the following description refers to the figures, unless otherwise indicated, the same numbers in different figures represent the same or similar elements. Example

[0028] like Figure 1 As shown, this embodiment provides an overhead optical cable environmental perception and status monitoring system based on BOTDR, including a BOTDR detection module, a distributed sensing optical cable, an environmental perception module, a data processing module, an early warning and display module, and a data storage module.

[0029] The distributed sensing optical cable uses armored single-mode optical fiber, with an outer layer of weather-resistant polytetrafluoroethylene (PTFE). It is laid parallel to the overhead optical cable and tightly fitted with specialized clamps, ensuring that the distributed sensing optical cable and the overhead optical cable simultaneously withstand mechanical forces and environmental influences. This guarantees that the strain and temperature information sensed by the distributed sensing optical cable accurately reflects the actual condition of the overhead optical cable. The length of the distributed sensing optical cable is the same as the monitoring length of the overhead optical cable, achieving full-length coverage monitoring of the overhead optical cable.

[0030] like Figure 2 As shown, the BOTDR detection module includes a pulsed laser generator, an optical coupler, a photodetector, and a signal preprocessing unit. The pulsed laser generator uses a narrow-pulse laser diode, capable of generating a narrow-pulse laser signal with a repetition frequency of 5 kHz and a pulse width of 10 ns. The optical coupler uses a 1×2 single-mode fiber coupler to couple the laser signal output from the pulsed laser generator to the distributed sensing optical cable, and to couple the backscattered Brillouin light signal generated in the distributed sensing optical cable to the photodetector. The photodetector uses an avalanche photodiode (APD) to convert the Brillouin scattered light signal into a weak electrical signal. The signal preprocessing unit consists of a low-noise amplifier, a bandpass filter, and a high-speed analog-to-digital converter. It amplifies and filters the electrical signal to suppress noise interference and converts the analog electrical signal into a digital signal, ultimately obtaining the raw strain data and raw temperature data. The BOTDR detection module has a Brillouin frequency shift measurement accuracy of ±0.5 MHz and a spatial resolution of 1 m, meeting the requirements for long-distance, high-precision monitoring.

[0031] The environmental sensing module consists of temperature and humidity sensors, wind speed sensors, light sensors, and vibration sensors. It is fixedly installed at key nodes such as the junction boxes of overhead optical cables, midpoints of the span, and windy areas in mountainous regions, using brackets. One environmental sensing module is installed at each key node. The temperature and humidity sensors are SHT30 type sensors, with a measurement range of -40℃ to 125℃ and 0 to 100%RH, with accuracies of ±0.3℃ and ±2%RH, respectively. The wind speed sensors are three-cup type anemometers, with a measurement range of 0 to 60 m / s and an accuracy of ±0.1 m / s. The light sensor is a BH1750 type sensor, with a measurement range of 0 to 65535 lx and an accuracy of ±1 lx. The vibration sensor is an MMA7361 type triaxial accelerometer, with a measurement range of ±1.5g and a sensitivity of 800 mV / g. The environmental sensing module uses a low-power microcontroller as the control core. The data collected by each sensor is processed by the microcontroller and then transmitted to the data processing module through the LoRa wireless communication module. The power supply is a combination of a 5W solar panel and a 12V lithium battery to ensure stable operation in environments without mains power.

[0032] like Figure 3As shown, the data processing module uses an industrial-grade embedded computer, which integrates a data receiving unit, a data calibration unit, a fusion analysis unit, and a state assessment unit. The data receiving unit receives raw strain and temperature data transmitted from the BOTDR detection module via an RS232 interface, and receives environmental parameters transmitted from the environmental sensing module via a LoRa gateway, performing time synchronization processing on the received data. The data calibration unit, based on the temperature data in the environmental parameters and combined with the temperature strain coefficient of the distributed sensing optical cable (pre-calibrated experimentally to 0.0001 / ℃), performs temperature compensation calibration on the raw strain data. The calibration formula is: ε = ε - k × (TT), where ε is the calibrated strain data, ε is the raw strain data, k is the temperature strain coefficient, T is the measurement temperature, and T is the preset reference temperature (set to 2). (5℃); The fusion analysis unit adopts a feature-level fusion method to normalize the calibrated strain data, original temperature data, and wind speed and vibration data in the environmental parameters, and extracts feature parameters such as mean, variance, peak value, and rate of change to construct the optical cable status feature vector; The status assessment unit presets a status assessment model based on the random forest algorithm. This model is trained with 1000 sets of historical monitoring data (including monitoring data corresponding to four states: normal state, slight abnormality, moderate abnormality, and severe abnormality) and corresponding status labels. The model classification accuracy reaches more than 95%. After inputting the optical cable status feature vector into the model, the status assessment result of the overhead optical cable is output.

[0033] like Figure 4 As shown, the early warning and display module includes an early warning unit and a display unit. The early warning unit uses an audible and visual alarm and a GSM SMS module. When the status assessment result is a minor anomaly, a yellow audible and visual alarm is triggered, and an early warning SMS (containing the abnormal location and abnormal parameters) is sent to the mobile phones of maintenance personnel. When the assessment result is a moderate anomaly, an orange audible and visual alarm is triggered, an SMS is sent, and a phone call is made to the maintenance personnel. When the assessment result is a severe anomaly, a red audible and visual alarm is triggered, an SMS is sent, a phone call is made to the maintenance personnel, and an alarm signal is sent to the monitoring center. The display unit uses a 10-inch touch screen with built-in monitoring data visualization software, which can display the spatial distribution map of the distributed sensing optical cable, the strain value, temperature value, environmental parameters, and status assessment results of each monitoring point in real time. It supports data query, historical curve display, and abnormal data annotation functions.

[0034] The data storage module combines a local solid-state drive (SSD) with a cloud server. The local SSD has a capacity of 1TB and is used to store nearly three months of monitoring data for easy retrieval. The cloud server uses Alibaba Cloud and uploads the monitoring data to the cloud in real time via a 4G network, enabling long-term data storage and remote access. The data is encrypted using the AES encryption algorithm to ensure data security.

[0035] In this embodiment, the system's workflow is as follows: After system startup, the BOTDR detection module emits pulsed laser light into the distributed sensing optical cable, continuously receives Brillouin scattering light signals, and processes them to obtain raw strain data and raw temperature data; the environmental perception module's sensors synchronously collect environmental parameters and transmit them to the data processing module via LoRa wireless communication; the data processing module performs time synchronization, temperature compensation calibration, feature fusion, and status assessment on the received data to obtain the status assessment results of the overhead optical cable; the early warning and display module triggers corresponding level early warnings based on the status assessment results and displays relevant data on the display unit; the data storage module stores various monitoring data and assessment results in real time for subsequent querying and analysis.

[0036] Brillouin Optical Time Domain Reflectometry (BOTDR) technology, based on the Brillouin scattering effect in optical fibers, enables distributed, long-distance, and high-precision monitoring of fiber strain and temperature, providing a new technical approach for the condition monitoring of overhead optical cables. However, existing BOTDR-based optical cable monitoring systems mostly focus only on the cable's own strain and temperature parameters, failing to fully integrate environmental parameters for comprehensive analysis. This results in insufficient accuracy of condition assessment results, making it difficult to effectively distinguish whether cable strain is caused by environmental factors (such as temperature and wind) or by cable faults (such as aging and damage), thus affecting the reliability of early warning. Therefore, there is an urgent need for a BOTDR-based overhead optical cable environmental sensing and condition monitoring system that can integrate the cable's own condition parameters with environmental parameters.

[0037] This invention has been described through embodiments. Those skilled in the art will understand that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the invention. Furthermore, under the teachings of this invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the invention. Therefore, this invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of this invention.

Claims

1. A BOTDR-based environmental sensing and condition monitoring system for overhead optical cables, characterized in that, include: The Brillouin Optical Time Domain Reflectometer (BOTDR) detection module, distributed sensing optical cable, environmental perception module, data processing module, and early warning and display module are included. The distributed sensing optical cable is laid in parallel with the overhead optical cable and closely attached to it, and is used to sense the strain and temperature information of itself and the overhead optical cable. The BOTDR detection module of the Brillouin optical time domain reflectometer is connected to the distributed sensing optical cable. It is used to emit pulsed laser to the distributed sensing optical cable and receive the Brillouin scattered light signal returned after being scattered by the distributed sensing optical cable. The Brillouin scattered light signal is preliminarily processed to obtain the original strain data and the original temperature data. The environmental sensing module is set at key nodes of the overhead optical cable and is used to collect environmental parameters of the environment in which the overhead optical cable is located. The data processing module is connected to the Brillouin Optical Time Domain Reflectometer (BOTDR) detection module and the environmental sensing module, respectively, and is used to perform fusion analysis on the raw strain data, raw temperature data and environmental parameters to obtain the status assessment results of the overhead optical cable. The early warning and display module is connected to the data processing module and is used to issue early warning prompts based on the status assessment results, and to display relevant monitoring data and assessment results.

2. The overhead optical cable environmental sensing and status monitoring system based on BOTDR according to claim 1, characterized in that, The BOTDR (Optical Time Domain Reflectometer) detection module includes a pulsed laser generator, an optical coupler, a photodetector, and a signal preprocessing unit. The pulsed laser generator generates narrow-pulse laser signals. The optical coupler couples the narrow-pulse laser signals to a distributed sensing optical cable and couples the Brillouin scattered light signals returned from the distributed sensing optical cable to the photodetector. The photodetector converts the Brillouin scattered light signals into electrical signals. The signal preprocessing unit amplifies, filters, and performs analog-to-digital conversion on the electrical signals to obtain raw strain data and raw temperature data.

3. The overhead optical cable environmental sensing and status monitoring system based on BOTDR according to claim 1, characterized in that, The environmental sensing module includes a temperature and humidity sensor, a wind speed sensor, a light sensor, and a vibration sensor; the temperature and humidity sensor is used to collect environmental temperature and humidity data; the wind speed sensor is used to collect environmental wind speed data; the light sensor is used to collect environmental light intensity data; and the vibration sensor is used to collect vibration data of the overhead optical cable.

4. The overhead optical cable environmental sensing and status monitoring system based on BOTDR according to claim 1, characterized in that, The data processing module includes a data receiving unit, a data calibration unit, a fusion analysis unit, and a state assessment unit. The data receiving unit is used to receive raw strain data, raw temperature data, and environmental parameters. The data calibration unit is used to perform temperature compensation calibration on the raw strain data based on the temperature and humidity data in the environmental parameters to obtain calibrated strain data. The fusion analysis unit is used to fuse the calibrated strain data, the original temperature data, and the wind speed and vibration data in the environmental parameters to extract the optical cable state feature vector; the state assessment unit is used to input the optical cable state feature vector into a preset state assessment model to obtain the state assessment result of the overhead optical cable, which includes normal, slightly abnormal, moderately abnormal, and severely abnormal.

5. The overhead optical cable environmental sensing and status monitoring system based on BOTDR according to claim 4, characterized in that, The preset state assessment model is a model built based on the random forest algorithm. The model is trained using historical monitoring data and corresponding optical cable actual state labels. The historical monitoring data includes historical strain data, historical temperature data, and historical environmental parameters.

6. The overhead optical cable environmental sensing and status monitoring system based on BOTDR according to claim 1, characterized in that, The early warning and display module includes an early warning unit and a display unit. The early warning unit triggers different levels of early warning based on the status assessment results: a yellow warning for mild anomalies, an orange warning for moderate anomalies, and a red warning for severe anomalies. The early warning methods include audible and visual warnings and SMS push notifications. The display unit uses a touch screen to display in real time the spatial distribution of the distributed sensing optical cable, the strain value, temperature value, environmental parameters, and status assessment results of each monitoring point.

7. The BOTDR-based overhead optical cable environmental sensing and status monitoring system according to claim 1, characterized in that, The distributed sensing optical cable uses armored single-mode optical fiber, and the outer layer of the armored single-mode optical fiber is provided with a weather-resistant protective layer, which is made of polytetrafluoroethylene.

8. The overhead optical cable environmental sensing and status monitoring system based on BOTDR according to claim 1, characterized in that, It also includes a data storage module, which is connected to the data processing module and is used to store raw monitoring data, calibrated data, status assessment results and historical early warning information. The data storage module adopts a combination of cloud storage and local storage.

9. The overhead optical cable environmental sensing and status monitoring system based on BOTDR according to claim 1, characterized in that, The pulsed laser repetition frequency of the BOTDR detection module of the Brillouin optical time domain reflectometer is 1kHz-10kHz, the Brillouin frequency shift measurement accuracy is not less than ±1MHz, and the spatial resolution is not less than 1m.

10. The overhead optical cable environmental sensing and status monitoring system based on BOTDR according to claim 3, characterized in that, Each sensor in the environmental sensing module adopts a low-power design, is powered by a combination of solar panels and lithium batteries, and supports LoRa wireless communication for data transmission with the data processing module.

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