Optical fiber coding and positioning integrated sensing device based on frequency division multiplexing and application method

Abstract

The invention relates to the technical field of optical fiber communication and sensing, and discloses an optical fiber coding and positioning integrated sensing device based on frequency division multiplexing and an application method, and the optical fiber coding and positioning integrated sensing device comprises a light source module, a coupler module, a frequency division multiplexing module, a sensing optical fiber network, a signal demodulation module, a positioning sensing module and a main control unit. According to the optical fiber coding and positioning integrated sensing device based on frequency division multiplexing and the application method thereof, a light source module generates broadband continuous optical signals, a coupler module realizes optical signal coupling and separation, a frequency division multiplexing module integrates sub optical signals, and an optical fiber sensing unit of a sensing optical fiber network senses and encodes external physical quantities. The positioning sensing module realizes accurate positioning, the signal demodulation module separates sub optical signals and extracts information, the main control unit operates in a coordinated manner, processes and analyzes data and outputs a result, all the modules cooperate to form an efficient and stable monitoring system, the requirements for multi-physical-quantity synchronous monitoring and accurate position positioning in a large-scale and long-distance scene are met, and the system performance is improved.

Description

Technical Field

[0001] The present invention relates to the field of optical fiber communication and sensing technology, and in particular to an optical fiber coding positioning integrated sensing device based on frequency division multiplexing and an application method thereof. Background Art

[0002] Fiber-optic communication uses light as an information carrier and optical fiber as a transmission medium to achieve efficient and long-distance transmission of information. Fiber-optic sensing technology uses the characteristics of parameters such as the amplitude, phase, polarization state and wavelength of light waves in optical fibers that change with external physical quantities such as temperature, pressure, and displacement to achieve the perception and measurement of external physical quantities.

[0003] Traditional fiber-optic sensing and monitoring systems often suffer from low signal transmission efficiency, difficulty in achieving simultaneous monitoring of multiple physical quantities, and difficulties in accurate positioning. The lack of efficient coordination between multiple modules results in insufficient stability and accuracy in complex monitoring environments, making it difficult to meet the requirements of large-scale, long-distance monitoring scenarios. Therefore, a fiber-optic coded positioning integrated sensing device and application method based on frequency division multiplexing is proposed to address these issues. Summary of the Invention

[0004] The purpose of the present invention is to provide an integrated optical fiber coding positioning sensing device based on frequency division multiplexing and an application method thereof, so as to solve the problems raised in the above background technology.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: an integrated optical fiber coding positioning sensing device based on frequency division multiplexing, comprising a light source module, a coupler module, a frequency division multiplexing module, a sensing optical fiber network, a signal demodulation module, a positioning sensing module and a main control unit; The light source module is used to generate a broadband continuous optical signal, providing a basic light source for frequency division multiplexing and sensing; The coupler module is connected to the light source module to achieve coupling and separation; The frequency division multiplexing module is connected to the coupler module and can multiplex optical sub-signals of different frequencies onto one optical carrier; The sensing optical fiber network is connected to the frequency division multiplexing module and includes at least one communication optical fiber and a plurality of optical fiber sensing units. The communication optical fiber transmits optical signals, and the optical fiber sensing units sense and encode changes in external physical quantities. The signal demodulation module is connected to the sensing fiber network, receives the return optical signal, separates the sub-optical signals through frequency division multiplexing demodulation technology, and extracts sensing and positioning information; The positioning sensor module is integrated into the sensing fiber network and is composed of multiple fiber optic sensing units with unique coding characteristics. It can sense and encode the physical quantity of a specific position to achieve precise positioning; The main control unit is electrically connected to the signal demodulation module and the positioning sensor module respectively, controls the workflow, coordinates the operation of the modules, processes and analyzes the demodulated sensor data and positioning information, and outputs the results.

[0006] Preferably, the optical fiber sensing unit includes an optical fiber Bragg grating (FBG), which is arranged at the core position of the optical fiber sensing unit and modulates the optical signal by periodic changes in the refractive index; a sensitive element, which is connected to the optical fiber Bragg grating (FBG), senses the change in physical quantity and converts it into a modulated signal; and a signal processing circuit, which is connected to the sensitive element and amplifies, filters and performs analog-to-digital conversion on the signal.

[0007] Preferably, the frequency division multiplexing module includes a frequency generator for generating local oscillation signals of different frequencies to provide the required subcarriers for frequency division multiplexing; a modulator connected to the frequency generator and the coupler module to modulate the subcarrier generated by the frequency generator with the optical signal input from the coupler module to multiplex the sub-optical signals of different frequencies onto one optical carrier; and a multiplexer connected to the modulator to perform further multiplexing processing on the modulated optical signal.

[0008] Preferably, the signal demodulation module includes a photodetector connected to the sensing optical fiber network to convert the optical signal into an electrical signal; a filter connected to the photodetector to filter out noise; and a demodulator connected to the filter to separate the sub-optical signals and extract information.

[0009] Preferably, the optical fiber sensing units in the positioning sensing module are arranged and combined according to certain coding rules, and the coding information of each optical fiber sensing unit contains its position information in the sensing optical fiber network. The main control unit decodes the demodulated coding information and can accurately determine the location where the physical quantity change occurs.

[0010] Preferably, the communication optical fiber adopts single-mode optical fiber, which has the characteristics of low loss and high bandwidth, can realize long-distance, high-speed optical signal transmission, and ensure the stability and reliability of the device in long-distance monitoring scenarios.

[0011] Preferably, the main control unit includes a data processing chip, a memory and a communication interface; the data processing chip performs filtering, noise reduction, feature extraction and other operations on the sensor data and positioning information output by the signal demodulation module; the memory is connected to the data processing chip to store processed data, configuration parameters and historical data, etc.; the communication interface is connected to the data processing chip to communicate with external devices such as computers and servers to realize data transmission and sharing, so as to facilitate users to remotely monitor and manage monitoring results.

[0012] On the other hand, the present application also provides an application method of an integrated fiber optic coding positioning sensing device based on frequency division multiplexing, comprising the following steps: S1 device deployment: laying a sensing fiber optic network in a predetermined layout in the monitoring area, installing the fiber optic sensing unit at a designated position according to the coding rules, and connecting the communication fiber optic cable; S2 light source emission and frequency division multiplexing: The light source module inputs preset parameters to generate a broadband continuous optical signal, which is coupled by the coupler module and then enters the frequency division multiplexing module. The optical sub-signals of different frequencies are multiplexed into the same optical carrier and transmitted to the sensor optical fiber network through the communication optical fiber. S3 Sensing and Encoding: External physical quantities such as strain and temperature act on the optical fiber sensing units in the sensing fiber network. The sensitive elements sense the changes and modulate the signals into the fiber Bragg grating (FBG). The multiplexed optical signal is then re-encoded and the sensing information is written into the optical signal. S4 signal transmission and reception: The encoded optical signal is returned to the signal demodulation module through the sensor fiber network, and the photoelectric detector converts it into an electrical signal. After filtering, the demodulator extracts the sensing and positioning information; S5 Data Processing and Positioning: The main control unit decodes sensor information, analyzes the type and value of physical quantity changes, parses positioning information, calculates position coordinates, stores them in memory, and outputs them to external devices through the communication interface to generate monitoring reports or trigger early warnings.

[0013] Compared with the prior art, the present invention has the following beneficial effects: First, the present invention generates a wide-band continuous optical signal through the light source module, providing a basic light source for subsequent frequency division multiplexing and sensing. The coupler module realizes the coupling and separation of the optical signal. The frequency division multiplexing module multiplexes the sub-optical signals of different frequencies onto an optical carrier. The optical fiber sensing unit in the sensing optical fiber network can sense the changes in external physical quantities and encode them. The positioning sensing module realizes precise positioning. The signal demodulation module receives the returned optical signal, separates the sub-optical signal through frequency division multiplexing demodulation technology, and extracts sensing and positioning information. The main control unit coordinates the operation of each module, processes and analyzes the demodulated sensing data and positioning information, and outputs the results. The modules work together to form a set of efficient, stable and accurate optical fiber sensing monitoring system, which can meet the needs of synchronous monitoring of multiple physical quantities and precise positioning in large-scale and long-distance monitoring scenarios, and effectively improve the overall performance of the monitoring system.

[0014] Second, in the signal demodulation module of the present invention, the photodetector converts the optical signal into an electrical signal, the filter filters out noise, and the demodulator separates the sub-optical signal and extracts information, providing high-quality signals for subsequent data processing. The main control unit includes a data processing chip, a memory and a communication interface. The data processing chip performs filtering, noise reduction, feature extraction and other operations on the sensor data and positioning information output by the signal demodulation module, thereby improving the accuracy and availability of the data. The memory stores processed data, configuration parameters and historical data, etc., which facilitates data management and query. The communication interface communicates with external devices such as computers and servers to realize data transmission and sharing, which facilitates users to remotely monitor and manage monitoring results. In the entire workflow, from signal generation, transmission, demodulation to data processing and output, each link works closely together, so that users can obtain accurate and comprehensive monitoring information in a timely manner, thereby improving the practicality and convenience of the monitoring system. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a flowchart of the overall process of the present invention; Figure 2 This is the overall connection diagram of the present invention.

[0016] Among them: 1. Light source module; 2. Coupler module; 3. Frequency division multiplexing module; 4. Sensing optical fiber network; 5. Signal demodulation module; 6. Positioning sensor module; 7. Main control unit. DETAILED DESCRIPTION

[0017] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0018] The present invention provides the following technical solutions: Example See also Figure 2 , an integrated optical fiber coding positioning sensing device based on frequency division multiplexing, comprising a light source module 1, a coupler module 2, a frequency division multiplexing module 3, a sensing optical fiber network 4, a signal demodulation module 5, a positioning sensing module 6 and a main control unit 7; The light source module 1 is used to generate a broadband continuous optical signal, providing a basic light source for frequency division multiplexing and sensing; The coupler module 2 is connected to the light source module 1 to achieve coupling and separation; The frequency division multiplexing module 3 is connected to the coupler module 2 and can multiplex optical sub-signals of different frequencies onto one optical carrier; The sensing optical fiber network 4 is connected to the frequency division multiplexing module 3 and includes at least one communication optical fiber and several optical fiber sensing units. The communication optical fiber transmits optical signals, and the optical fiber sensing units sense and encode changes in external physical quantities. The signal demodulation module 5 is connected to the sensing optical fiber network 4, receives the return optical signal, separates the sub-optical signals through frequency division multiplexing demodulation technology, and extracts the sensing and positioning information; The positioning sensor module 6 is integrated into the sensing optical fiber network 4 and is composed of multiple optical fiber sensing units with unique coding characteristics. It can sense and encode the physical quantity of a specific position to achieve accurate position positioning; The main control unit 7 is electrically connected to the signal demodulation module 5 and the positioning sensor module 6 respectively, controls the workflow, coordinates module operations, processes and analyzes the demodulated sensor data and positioning information, and outputs the results.

[0019] The fiber optic sensing unit includes a fiber Bragg grating (FBG), which is located at the core of the unit and modulates the optical signal through periodic changes in the refractive index; a sensitive element, which is connected to the fiber Bragg grating, senses changes in physical quantities and converts them into modulated signals; and a signal processing circuit, which is connected to the sensitive element and amplifies, filters, and performs analog-to-digital conversion on the signal.

[0020] A fiber Bragg grating (FBG) is set as the core modulation element in the fiber optic sensing unit, and its periodic refractive index variation characteristics are used to modulate the optical signal, which can accurately respond to the influence of changes in external physical quantities on the optical signal and achieve high-sensitivity optical signal modulation. The sensitive element is connected to the fiber Bragg grating, which can directly sense subtle changes in external physical quantities and convert them into modulated signals, enhancing the sensing unit's ability to perceive changes in physical quantities. The signal processing circuit amplifies, filters and performs analog-to-digital conversion on the signal output by the sensitive element, effectively improving the quality and stability of the signal, facilitating the accurate transmission and demodulation analysis of subsequent signals, and ensuring the accuracy and reliability of the sensing data.

[0021] The frequency division multiplexing module 3 includes a frequency generator for generating local oscillator signals of different frequencies to provide the subcarriers required for frequency division multiplexing; a modulator, connected to the frequency generator and coupler module 2, modulates the subcarriers generated by the frequency generator with the optical signal input from the coupler module 2, and multiplexes the sub-optical signals of different frequencies onto one optical carrier; and a multiplexer, connected to the modulator, further multiplexes the modulated optical signals.

[0022] The frequency generator in the frequency division multiplexing module 3 can generate local oscillation signals of different frequencies, providing stable and diverse subcarriers for frequency division multiplexing, so that sub-optical signals of different frequencies can be effectively distinguished in subsequent processes; the modulator modulates the subcarrier generated by the frequency generator with the optical signal input from the coupler module 2, and multiplexes the sub-optical signals of different frequencies onto one optical carrier, making full use of the bandwidth resources of the optical carrier, greatly improving the transmission efficiency of the optical signal, and reducing the number and cost of required optical fibers; the multiplexer further multiplexes the modulated optical signal, optimizing the multiplexing structure of the optical signal, making the multiplexed optical signal more stable and efficient to transmit, and ensuring the performance and stability of the entire sensing device in multi-channel, multi-physical quantity monitoring scenarios.

[0023] The signal demodulation module 5 includes a photodetector connected to the sensing optical fiber network 4 to convert the optical signal into an electrical signal; a filter connected to the photodetector to filter out noise; and a demodulator connected to the filter to separate the sub-optical signals and extract information.

[0024] The photoelectric detector in the signal demodulation module 5 is connected to the sensing optical fiber network 4, and can quickly and accurately convert the weak optical signal returned by the sensing optical fiber network 4 into an electrical signal, providing a basis for subsequent signal processing; the filter is connected to the photoelectric detector, which can effectively filter out noise interference in the electrical signal, improve the signal-to-noise ratio of the signal, and make the signal clearer and more accurate; the demodulator is connected to the filter, which can accurately separate the sub-optical signals and extract the sensing and positioning information therein, realizing efficient demodulation of complex optical signals, ensuring the accuracy and completeness of the sensing data and positioning information obtained from the optical signal, and providing a reliable basis for subsequent data processing and analysis.

[0025] The optical fiber sensing units in the positioning sensing module 6 are arranged and combined according to certain coding rules. The coding information of each optical fiber sensing unit contains its position information in the sensing optical fiber network. The main control unit 7 decodes the demodulated coding information and can accurately determine the location where the physical quantity change occurs.

[0026] The optical fiber sensing units in the positioning sensing module 6 are arranged and combined according to certain coding rules, so that the coding information of each optical fiber sensing unit contains its position information in the sensing optical fiber network 4. This unique coding method provides a basis for subsequent positioning; the main control unit 7 decodes the demodulated coding information and can accurately parse out the position information corresponding to each optical fiber sensing unit. Combined with the sensing information, it can accurately determine the position where the physical quantity changes, realizing a high-precision positioning function, meeting the demand for accurate monitoring of physical quantity changes at specific positions in complex monitoring environments, and improving the positioning accuracy and practicality of the entire sensing device.

[0027] The communication optical fiber adopts single-mode optical fiber, which has the characteristics of low loss and high bandwidth. It can realize long-distance and high-speed optical signal transmission, ensuring the stability and reliability of the device in long-distance monitoring scenarios.

[0028] The communication optical fiber 4 adopts single-mode optical fiber. Single-mode optical fiber has low loss characteristics and can reduce the energy loss of optical signals during transmission, so that the optical signal can maintain a higher intensity over a longer distance, thereby realizing long-distance optical signal transmission; at the same time, the high bandwidth characteristics of single-mode optical fiber allow it to transmit high-speed optical signals, which can meet the monitoring needs of large-scale and high data volume; in long-distance monitoring scenarios, the low loss and high bandwidth characteristics of single-mode optical fiber ensure the stability and reliability of optical signal transmission, reduce signal attenuation and distortion, ensure that the sensing device can accurately acquire and transmit sensing data over a long distance, and improve the applicability and monitoring effect of the sensing device.

[0029] The main control unit 7 includes a data processing chip, a memory and a communication interface; the data processing chip performs operations such as filtering, noise reduction, and feature extraction on the sensor data and positioning information output by the signal demodulation module 5; the memory is connected to the data processing chip to store processed data, configuration parameters, and historical data; the communication interface is connected to the data processing chip to communicate with external devices such as computers and servers to realize data transmission and sharing, making it convenient for users to remotely monitor and manage monitoring results.

[0030] The data processing chip in the main control unit 7 performs filtering, noise reduction, feature extraction and other operations on the sensor data and positioning information output by the signal demodulation module 5, which can effectively remove noise and interference in the data, extract key feature information, improve the quality and availability of the data, and provide an accurate data basis for subsequent data analysis and decision-making; the memory is connected to the data processing chip, and can store processed data, configuration parameters and historical data, etc., which is convenient for long-term storage and management of data, and facilitates subsequent data query, analysis and comparison, and provides data support for the optimization and improvement of the monitoring system; the communication interface is connected to the data processing chip, and realizes communication with external devices such as computers and servers. It can transmit and share processed data in real time, which is convenient for users to remotely monitor and manage monitoring results. Users can obtain monitoring data anytime and anywhere, and timely understand the situation in the monitoring area, which improves the convenience and practicality of the monitoring system, and also facilitates further analysis and processing of monitoring data to provide support for decision-making.

[0031] On the other hand, see Figure 1 , the present application also provides an application method of an integrated optical fiber coding positioning sensing device based on frequency division multiplexing, comprising the following steps: S1 device deployment: laying a sensing optical fiber network 4 in a monitoring area according to a predetermined layout, installing the optical fiber sensing unit at a designated position according to the coding rule, and connecting the communication optical fiber; S2 Light Source Emission and Frequency Division Multiplexing: Light source module 1 inputs preset parameters to generate a broadband continuous optical signal, which is coupled by coupler module 2 and then enters frequency division multiplexing module 3, multiplexing sub-optical signals of different frequencies into the same optical carrier and transmitted to sensor optical fiber network 4 through communication optical fiber; S3 Sensing and Encoding: External physical quantities such as strain and temperature act on the optical fiber sensing units in the sensing optical fiber network 4. The sensitive elements sense the changes and modulate the signals into the fiber Bragg grating, which performs secondary encoding on the multiplexed optical signal and writes the sensing information into the optical signal. S4 signal transmission and reception: The encoded optical signal is returned to the signal demodulation module 5 via the sensor optical fiber network 4, where it is converted into an electrical signal by the photodetector. After filtering, the demodulator extracts the sensing and positioning information. S5 Data processing and positioning: The main control unit 7 decodes the sensor information, analyzes the type and value of the physical quantity change, parses the positioning information, calculates the position coordinates, stores them in the memory, and outputs them to the external device through the communication interface to generate a monitoring report or trigger an early warning.

[0032] During use, a sensing fiber optic network 4 is laid in the monitoring area according to a predetermined layout, the fiber optic sensing unit is installed at the designated position according to the coding rules and connected to the communication fiber to complete the device deployment, then the light source module 1 inputs the preset parameters to generate a wide-band continuous optical signal, which enters the frequency division multiplexing module 3 after coupling through the coupler module 2. The module multiplexes the sub-optical signals of different frequencies into the same optical carrier and transmits them to the sensing fiber optic network 4 through the communication fiber optic. External physical quantities act on the fiber optic sensing units in the sensing fiber optic network 4, and the sensitive elements sense the changes and modulate the signals to the fiber optic Bragg grating for secondary encoding. The encoded optical signal returns to the signal demodulation module 5, is converted into an electrical signal by the photoelectric detector, and then filtered by the filter and processed by the demodulator to extract the sensing and positioning information. Finally, the main control unit 7 decodes the sensing information, analyzes the changes in physical quantities and parses the positioning information, calculates the position coordinates, associates and stores the data and outputs it to the external device through the communication interface to generate a monitoring report or trigger an early warning.

[0033] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and alterations may be made to the embodiments without departing from the principles and spirit thereof, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. An integrated optical fiber coding positioning sensing device based on frequency division multiplexing, characterized by: It includes a light source module (1), a coupler module (2), a frequency division multiplexing module (3), a sensing optical fiber network (4), a signal demodulation module (5), a positioning sensor module (6) and a main control unit (7); The light source module (1) is used to generate a broadband continuous optical signal, providing a basic light source for frequency division multiplexing and sensing; The coupler module (2) is connected to the light source module (1) to achieve coupling and separation; The frequency division multiplexing module (3) is connected to the coupler module (2) and can multiplex sub-optical signals of different frequencies onto one optical carrier; The sensing optical fiber network (4) is connected to the frequency division multiplexing module (3), and comprises at least one communication optical fiber and a plurality of optical fiber sensing units, wherein the communication optical fiber transmits optical signals, and the optical fiber sensing units sense and encode changes in external physical quantities; The signal demodulation module (5) is connected to the sensing optical fiber network (4), receives the return optical signal, separates the sub-optical signals through frequency division multiplexing demodulation technology, and extracts sensing and positioning information; The positioning sensing module (6) is integrated in the sensing optical fiber network (4), and is composed of a plurality of optical fiber sensing units with unique coding characteristics, which can sense and encode physical quantities at specific locations to achieve accurate position positioning; The main control unit (7) is electrically connected to the signal demodulation module (5) and the positioning sensor module (6), controls the workflow, coordinates module operations, processes and analyzes demodulated sensor data and positioning information, and outputs the results.

2. The integrated optical fiber coding positioning sensing device based on frequency division multiplexing according to claim 1, characterized in that: The optical fiber sensing unit includes an optical fiber Bragg grating (FBG), which is arranged at the core position of the optical fiber sensing unit and modulates the optical signal through periodic changes in the refractive index; a sensitive element, which is connected to the optical fiber Bragg grating, senses the changes in physical quantities and converts them into modulated signals; and a signal processing circuit, which is connected to the sensitive element and amplifies, filters and performs analog-to-digital conversion on the signal.

3. The integrated optical fiber coding positioning sensing device based on frequency division multiplexing according to claim 1, characterized in that: The frequency division multiplexing module (3) includes a frequency generator for generating local oscillation signals of different frequencies to provide the required subcarriers for frequency division multiplexing; The modulator is connected to the frequency generator and the coupler module (2), modulating the subcarrier generated by the frequency generator with the optical signal input from the coupler module (2), and multiplexing the sub-optical signals of different frequencies onto one optical carrier; the multiplexer is connected to the modulator, and further multiplexing the modulated optical signal.

4. The integrated optical fiber coding positioning sensing device based on frequency division multiplexing according to claim 1, characterized in that: The signal demodulation module (5) includes a photodetector connected to the sensing optical fiber network (4) for converting optical signals into electrical signals; a filter connected to the photodetector for filtering out noise; and a demodulator connected to the filter for separating sub-optical signals and extracting information.

5. The integrated optical fiber coding positioning sensing device based on frequency division multiplexing according to claim 1, characterized in that: The optical fiber sensing units in the positioning sensing module (6) are arranged and combined according to certain coding rules. The coding information of each optical fiber sensing unit contains its position information in the sensing optical fiber network. The main control unit (7) decodes the demodulated coding information to accurately determine the location where the physical quantity change occurs.

6. The integrated optical fiber coding positioning sensing device based on frequency division multiplexing according to claim 1, characterized in that: The communication optical fiber adopts single-mode optical fiber, which has the characteristics of low loss and high bandwidth, and can realize long-distance, high-speed optical signal transmission, ensuring the stability and reliability of the device in long-distance monitoring scenarios.

7. The integrated optical fiber coding positioning sensing device based on frequency division multiplexing according to claim 1, characterized in that: The main control unit (7) includes a data processing chip, a memory and a communication interface; the data processing chip performs operations such as filtering, noise reduction and feature extraction on the sensor data and positioning information output by the signal demodulation module (5); the memory is connected to the data processing chip and stores processed data, configuration parameters and historical data; the communication interface is connected to the data processing chip and communicates with external devices such as computers and servers to realize data transmission and sharing, so as to facilitate users to remotely monitor and manage monitoring results.

8. An application method of a fiber optic coding positioning integrated sensing device based on frequency division multiplexing, applied to the fiber optic coding positioning integrated sensing device based on frequency division multiplexing according to claims 1-7, characterized in that: The following steps are involved: S1 Device deployment: Lay the sensor fiber network (4) in the monitoring area according to the predetermined layout, install the fiber optic sensor units at the designated positions according to the coding rules, and connect the communication fiber optic cables; S2 light source emission and frequency division multiplexing: The light source module (1) inputs preset parameters to generate a broadband continuous optical signal, which is coupled by the coupler module (2) and then enters the frequency division multiplexing module (3), multiplexing the sub-light signals of different frequencies into the same optical carrier and transmitting them to the sensor optical fiber network (4) through the communication optical fiber; S3 Sensing and Encoding: External physical quantities such as strain and temperature act on the optical fiber sensing unit in the sensing optical fiber network (4). The sensitive element senses the change and modulates the signal to the fiber Bragg grating, performs secondary encoding on the multiplexed optical signal, and writes the sensing information into the optical signal; S4 signal transmission and reception: The encoded optical signal is returned to the signal demodulation module (5) via the sensor optical fiber network (4), and the photoelectric detector converts it into an electrical signal. After filtering, the demodulator extracts the sensing and positioning information; S5 Data processing and positioning: The main control unit (7) decodes the sensor information, analyzes the type and value of the physical quantity change, parses the positioning information, calculates the position coordinates, stores them in the memory, and outputs them to the external device through the communication interface to generate a monitoring report or trigger an early warning.

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