Long-distance infrastructure multi-parameter monitoring optical fiber composite sensing array and edge demodulation device

Abstract

The application belongs to the technical field of optical fiber sensing, and particularly relates to a long-distance infrastructure multi-parameter monitoring optical fiber composite sensing array and edge demodulation device. The optical fiber composite sensing array comprises a distributed temperature sensing channel, a distributed vibration sensing channel, an optical fiber grating sensing channel, a main sensing optical fiber, a wavelength division multiplexing assembly, a wavelength separation device and a digitization system. The edge demodulation device comprises a time synchronization mechanism, a data processing flow and a multi-parameter fusion model. The application integrates the distributed temperature sensing channel, the distributed vibration sensing channel and the optical fiber grating sensing channel by using a single main sensing optical fiber, and is equipped with the edge demodulation device. A multi-source data fusion model is constructed, full-field synchronous reconstruction of a temperature field, a vibration event and a strain distribution is realized, and high-precision synchronous monitoring and real-time decision of multiple physical quantities are realized.

Description

Technical Field

[0001] This invention belongs to the field of fiber optic sensing technology, specifically relating to a fiber optic composite sensing array and edge demodulation device for multi-parameter monitoring of long-distance infrastructure. Background Technology

[0002] Distributed fiber optic sensing (DOFS) technology, with its unique large-scale continuous spatial sensing capability, fully integrates the light transmission and sensing characteristics of optical fibers. It can simultaneously acquire the distribution information of the measured field in both time and space, demonstrating irreplaceable application potential in fields such as infrastructure health monitoring. Distributed fiber optic sensing technologies based on different physical mechanisms have been extensively studied, mainly including Rayleigh scattering, Raman scattering, Brillouin scattering, fiber interferometers, and fiber Bragg gratings (FBGs). Although research on single-mechanism sensing technologies is relatively in-depth, their application in complex engineering scenarios still faces significant limitations.

[0003] Current research on distributed fiber optic sensors based on single mechanisms is relatively in-depth. For example, patent application CN101324424A discloses a novel fiber optic Brillouin optical time-domain analyzer, which utilizes the broadband nonlinear optical amplification effect of fiber and related methods to analyze the strain and temperature effects of Brillouin scattered light in an optical time-domain manner. It includes a narrowband single-frequency fiber laser, fiber splitter, pulse modulator, two fiber circulators, a heterodyne receiver, digital signal processor, fiber grating filter, single-mode fiber, and a continuously operating fiber Raman pump laser. Strain / temperature measurement is mainly achieved through fiber Brillouin optical time-domain analysis (BOTDA), utilizing the nonlinear amplification effect of fiber to improve the signal-to-noise ratio. However, this technology is only suitable for static or quasi-static parametric monitoring and cannot capture high-frequency vibration events such as mechanical shocks or pipe leaks. Furthermore, the system is highly complex, requiring multiple stages of pump lasers and circulators.

[0004] Chinese patent CN1232846C discloses a Mach-Zehnder interferometric sensing device based on a micro-bent transmission waveguide. One end of the input waveguide is connected to a laser source, and the other end is connected to one end of a first coupler, which in turn connects to one end of a bent sensing waveguide arm and one end of a bent reference waveguide arm. These are then connected to the output waveguide via a second coupler. A sensing sample cell is mounted on the outer side of the sensing waveguide arm, and a standard sample cell is mounted on the outer side of the reference waveguide arm. This patent proposes an interferometric sensing device based on a micro-bent waveguide, detecting external disturbances through the phase difference between the reference arm and the sensing arm. However, this type of solution has limited spatial resolution, typically >10m, and struggles to distinguish between temperature and strain coupling effects, making it susceptible to environmental noise interference.

[0005] Patent application CN102818657 A discloses a remote distributed Raman temperature sensor based on EDFA amplification technology. Its key feature is the use of at least two sensing fibers, with two circulators and an amplifier positioned between adjacent fibers. The signal from the preceding sensing fiber sequentially passes through a first circulator, an EDFA amplifier, and a second circulator before entering the following sensing fiber. The back-reflected signal from the following sensing fiber sequentially passes through a second circulator and a first circulator before returning to the preceding sensing fiber and being sent to a data acquisition unit via a wavelength division multiplexer. This patent uses EDFA amplification technology to extend the Raman temperature measurement distance, achieving a multi-stage fiber optic link through cascaded circulators and amplifiers. However, this technology cannot simultaneously sense vibration or strain, and the additional noise introduced by the amplifier leads to a decrease in temperature measurement accuracy.

[0006] The existing technologies mentioned above are limited by their respective technical characteristics, making it difficult to simultaneously perform high-precision collaborative monitoring of static parameters such as temperature and long-term strain, and dynamic parameters such as vibration and transient stress in some complex engineering scenarios such as oil pipelines, high-voltage cables, and bridges. Summary of the Invention

[0007] To facilitate research on multi-parameter distributed optical fiber sensors, this invention provides an optical fiber composite sensor array and edge demodulation device for multi-parameter monitoring of long-distance infrastructure.

[0008] The specific technical solution of this invention is as follows:

[0009] A fiber optic composite sensor array and edge demodulation device for multi-parameter monitoring of long-distance infrastructure, wherein the fiber optic composite sensor array includes:

[0010] A distributed temperature sensing channel is provided with a laser, an acousto-optic modulator and a detection module. The acousto-optic modulator generates controllable light pulses, and the detection module monitors and adjusts the pulse power.

[0011] A distributed vibration sensing channel is provided with a laser, a phase modulator, and a detection module. The phase modulator is loaded with a highly complex coded sequence, and the detection module verifies the integrity of the modulated signal.

[0012] The fiber optic grating sensing channel is equipped with a laser, a tunable filter, and a circulator. The tunable filter generates a wavelength scanning beam, and the circulator enables directional transmission of optical signals.

[0013] The main sensing fiber has an internal FBG array that enables selective reflection of specific wavelengths and maintains transmission of the transmission wavelength.

[0014] The wavelength division multiplexing component includes three independent wavelength division multiplexers. The WDM1 port, WDM2 port and WDM3 port respectively receive three channels of optical signals and are fed into a single main sensing fiber through an optical fiber coupler.

[0015] A wavelength separation device demultiplexes the backscattered Rayleigh light and directs signals of different wavelengths to the DTS detector and the DVS detector, respectively.

[0016] The digital system collects and processes all signals after photoelectric conversion;

[0017] The edge demodulation device includes:

[0018] The time synchronization mechanism includes a GPS receiver unit, a PTP precision clock protocol unit, and an FPGA timestamp alignment circuit.

[0019] The data processing stream is equipped with a signal acquisition unit and a feature extraction unit that work in parallel. The feature extraction unit executes the temperature analysis module, vibration analysis module and strain analysis module in parallel.

[0020] The multi-parameter fusion model integrates multi-dimensional information such as temperature, vibration, and strain for joint processing and analysis, and outputs decision instructions.

[0021] Furthermore, the multi-parameter fusion model also includes an anomaly decision engine and a multi-mode alarm output module. The anomaly decision engine implements a hierarchical judgment strategy, combined with dynamic threshold adjustment and spatiotemporal correlation analysis. The multi-mode alarm output module drives the on-site audible and visual alarm device through relay control, uploads equipment status data through the industrial communication interface, and transmits location information to the central monitoring platform in real time through a high-speed network channel.

[0022] Furthermore, the FBG array inside the main sensing fiber is arranged in a regular pattern, and a set of grating units with characteristic reflection spectra is set at certain intervals. The grating reflection signal returns to the circulator along the original transmission path, is input to the circulator port two and output to the circulator port three, and is guided to the FBG detector.

[0023] Furthermore, the time synchronization mechanism adopts a dual-redundant design architecture.

[0024] Furthermore, the GPS receiving unit is used to obtain the absolute time reference provided by satellite positioning, the PTP precision clock protocol unit is used to achieve high-precision time synchronization in a network environment, and the FPGA timestamp alignment circuit performs intelligent calibration and compensation on the two input time signals.

[0025] Furthermore, the temperature analysis module is used to identify spatial temperature anomalies, the vibration analysis module calculates energy distribution through frequency domain transformation, and the strain analysis module implements window detection for dynamic baseline calibration.

[0026] Furthermore, the first laser is a distributed feedback laser with a wavelength of 1550nm, and the first laser is connected to an acousto-optic modulator via a polarization-maintaining fiber.

[0027] Furthermore, the second laser provides a 1650nm light source, which enters the phase modulator after polarization optimization.

[0028] Furthermore, the entire optical transmission line employs a multi-stabilization design, ensuring wavelength characteristics stability through thermal management and mechanical protection.

[0029] In summary, compared with the prior art, the above-described technical solutions conceived by this invention can achieve the following beneficial effects:

[0030] This invention employs wavelength multiplexing technology to achieve synchronous sensing of multiple parameters through single-fiber transmission. By using a specific wavelength allocation scheme, it enables physical isolation of three functions—distributed temperature sensing, vibration detection, and fiber optic strain measurement—at the optical layer, thus completely solving the crosstalk problem of traditional multi-system parallel connection.

[0031] The edge demodulation device has a built-in dual-redundant time synchronization mechanism, combined with the parallel acquisition architecture of the original signal, to ensure that the time alignment accuracy of multi-source heterogeneous data meets industrial application standards.

[0032] The innovative multi-level data processing stream eliminates data transmission bandwidth limitations through localized feature extraction. The temperature analysis module can identify abnormal temperature characteristics, the vibration analysis module establishes a frequency domain energy distribution model, and the strain analysis module implements dynamic baseline calibration. The outputs of the three modules generate joint decision commands through a multi-parameter fusion model, triggering multi-mode alarm outputs, which significantly improves the accuracy and timeliness of anomaly identification.

[0033] In addition, the system adopts a modular optoelectronic design to achieve hardware layer decoupling, and supports wavelength configuration reconfiguration through pluggable wavelength division multiplexing components, giving the system the ability to adapt to multiple scenarios;

[0034] The multi-protection design enables the device to maintain measurement stability in harsh environments. Compared with traditional solutions, this invention has made substantial progress in terms of expanding monitoring dimensions, improving real-time response, environmental anti-interference capability and system reliability, providing a new generation of technology paradigm for the field of fiber optic sensing. Attached Figure Description

[0035] Figure 1 This is a structural block diagram of the three-wavelength composite transmission architecture of the fiber optic composite sensing array of the present invention;

[0036] Figure 2 This is a structural block diagram of the edge demodulation device of the present invention;

[0037] Figure 3This is a schematic diagram of the principle structure of the present invention.

[0038] The attached figures are labeled as follows:

[0039] 1-Laser 1; 2-Acousto-optic modulator; 3-Detection module 1; 4-WDM1 port; 5-Laser 2; 6-Phase modulator; 7-Detection module 2; 8-WDM2 port; 9-Laser 3; 10-Tunable filter; 11-Fiber optic coupler; 12-WDM3 port; 13-Main sensing fiber; 14-FBG array; 15-FBG detector; 16-Wavelength separation device; 17-DTS detector; 18-DVS detector; 19-Edge demodulation device; 20- - Time synchronization mechanism; 21- Data processing stream; 22- Multi-parameter fusion model; 23- GPS receiving unit; 24- PTP precision clock protocol unit; 25- FPGA timestamp alignment circuit; 26- Signal acquisition unit; 27- Feature extraction unit; 28- Temperature analysis module; 29- Vibration analysis module; 30- Strain analysis module; 31- Anomaly decision engine; 32- Multi-mode alarm output module; 33- Relay control; 34- Industrial communication interface; 35- High-speed network channel. Detailed Implementation

[0040] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this invention.

[0041] Combined with appendix Figure 1-3 As shown, a fiber optic composite sensor array and edge demodulation device for multi-parameter monitoring of long-distance infrastructure are disclosed. The fiber optic composite sensor array includes:

[0042] The distributed temperature sensing channel is equipped with a laser 1, an acousto-optic modulator 2, and a detection module 3. The acousto-optic modulator 2 generates controllable light pulses, and the detection module 3 implements pulse power monitoring and feedback adjustment. That is, the detection module 3 realizes real-time monitoring and calibration of pulse energy, and after ensuring that the pulse quality is stable, it is connected to the port 4 of the high isolation wavelength division multiplexer WDM1.

[0043] The distributed vibration sensing channel is equipped with a laser 5, a phase modulator 6, and a detection module 7. The phase modulator 6 is loaded with a highly complex coding sequence. The detection module 7 verifies the integrity of the modulation signal. That is, the detection module 7 verifies the integrity of the modulation signal to ensure that the signal quality meets the standard before connecting it to the WDM2 port 8 of the wavelength division multiplexer.

[0044] The fiber optic grating sensing channel is equipped with a laser 39, a tunable filter 10, and a circulator. The laser 39 mainly provides a 1545nm light source. After being precisely filtered by the tunable filter 10, a narrow linewidth scanning beam is formed. After the optical signal is directionally transmitted through the circulator, that is, the input is at port 1 of the circulator and the output is at port 2 of the circulator, which is connected to port 12 of the wavelength division multiplexer WDM3.

[0045] The main sensing fiber 13 has an internal FBG array 14 that enables selective reflection of specific wavelengths and maintains transmission of transmission wavelengths.

[0046] The wavelength division multiplexing component includes three independent wavelength division multiplexers. WDM1 port 4, WDM2 port 8 and WDM3 port 12 respectively receive three channel optical signals and are connected to a single main sensing fiber 13 through fiber coupler 11.

[0047] The wavelength separation device 16 demultiplexes the backscattered Rayleigh light and directs the different wavelength signals to the DTS detector 17 and the DVS detector 18 respectively. That is, the 1550nm band signal is received by the temperature-controlled optimized DTS detector 17, while the 1650nm band signal is input to the ultra-low noise DVS detector 18. The unique wavelength allocation scheme realizes the high isolation parallel transmission of the three sensing channels, laying the physical foundation for multi-parameter synchronous monitoring.

[0048] The digital system collects and processes all signals after photoelectric conversion;

[0049] The edge demodulation device 19 is the intelligent processing hub of the entire fiber optic sensing system, and it includes:

[0050] The time synchronization mechanism 20 includes a GPS receiver unit 23, a PTP precision clock protocol unit 24, and an FPGA timestamp alignment circuit 25.

[0051] The data processing stream 21 is equipped with a signal acquisition unit 26 and a feature extraction unit 27 that work in parallel. The signal acquisition unit 26 acquires signals from the FBG, DTS and DVS detectors synchronously received by the digitization system.

[0052] The feature extraction unit 27 executes the temperature analysis module 28, the vibration analysis module 29, and the strain analysis module 30 in parallel.

[0053] The multi-parameter fusion model 22 integrates multi-dimensional information such as temperature, vibration, and strain for joint processing and analysis, and outputs decision instructions. That is, the multi-parameter fusion model 22 makes joint decisions on the three-channel characteristic parameters in order to build a comprehensive understanding of the working conditions.

[0054] Specifically, the multi-parameter fusion model 22 also includes an anomaly decision engine 31 and a multi-mode alarm output module 32. The anomaly decision engine 31 implements a hierarchical judgment strategy, combines dynamic threshold adjustment and spatiotemporal correlation analysis, and then triggers the multi-mode alarm output module 32 based on the fusion result. The multi-mode alarm output module 32 includes a relay control 33, an industrial communication interface 34, and a high-speed network channel 35. The relay control 33 drives the on-site audible and visual alarm device, the industrial communication interface 34 uploads equipment status data, and the high-speed network channel 35 transmits location information to the central monitoring platform in real time.

[0055] Specifically, the FBG array 14 inside the main sensing fiber 13 is arranged in a regular pattern, and a group of grating units with characteristic reflection spectra is set at certain intervals. Each group of grating units contains multiple characteristic reflection wavelengths, and the total reflectivity is lower than a set threshold. The grating reflection signal returns to the circulator along the original transmission path, and after port switching (i.e., input at circulator port two and output at circulator port three), it is guided to the FBG detector 15, which is a high-sensitivity FBG photodetector.

[0056] Specifically, the time synchronization mechanism 20 adopts a dual-path redundancy design architecture.

[0057] Specifically, the GPS receiving unit 23 is used to obtain the absolute time reference provided by satellite positioning, the PTP precision clock protocol unit 24 is used to achieve high-precision time synchronization in a network environment, and the FPGA timestamp alignment circuit 25 performs intelligent calibration and compensation on the two input time signals to ensure that the time alignment accuracy of each detection module in the whole system reaches the industrial-grade standard.

[0058] Specifically, the temperature analysis module 28, i.e. temperature gradient analysis, is used to identify spatial temperature anomalies, focusing on identifying temperature anomalies such as pipeline leaks; the vibration analysis module 29, i.e. vibration energy spectrum analysis, calculates energy distribution through frequency domain transformation, which can accurately capture intrusion events and mechanical fault characteristics; and the strain analysis module 30, i.e. strain extreme value tracking, implements window detection for dynamic baseline calibration, which can continuously monitor the deformation state of structures such as bridges.

[0059] Specifically, the laser 1 is a distributed feedback laser with a wavelength of 1550nm, and the laser 1 is connected to the acousto-optic modulator 2 through a polarization-maintaining fiber. The acousto-optic modulator 2 generates a precise and controllable optical pulse signal under the drive of the digital control system.

[0060] Specifically, the second laser 5 provides a 1650nm light source, which enters the phase modulator 6 after polarization optimization.

[0061] Specifically, the entire optical transmission line adopts a multi-stabilization design, ensuring wavelength characteristics stability through thermal management and mechanical protection, so as to maintain stable operation in harsh environments and provide reliable decision support for infrastructure safety monitoring.

[0062] To ensure optical stability, corresponding laser temperature control modules can be installed at each laser to maintain the stability of the laser source wavelength; fiber stress relief structures can be installed on the entire system's transmission optical path to suppress transmission loss; and optical isolation components can be installed to block reverse interference signals.

[0063] The three-channel optical signals are physically isolated and transmitted within a single fiber by wavelength allocation; the wavelength selective separation of reflected signals and transmitted scattered light is achieved using the FBG array 14; the time-domain alignment of multi-channel signals is established based on the dual-redundant time synchronization mechanism 20, i.e., receiving satellite timing signals and network synchronization signals, and timestamp alignment is achieved through logic device interpolation compensation; temperature scattering features, vibration phase features, and strain wavelength features are extracted in parallel by the feature extraction unit 27; a joint decision command is generated by the multi-parameter fusion model 22 with an adaptive fusion algorithm; and a multi-mode alarm output module 32 is triggered; the adaptive fusion algorithm adopts a machine learning model, and the input parameters include temperature gradient value, vibration energy value, and strain offset.

[0064] The specific implementation path of this invention is as follows:

[0065] In the optical signal generation stage, the distributed temperature sensing channel uses a 1550nm laser source to generate adjustable pulse width optical pulses via an acousto-optic modulator 2, and maintains pulse energy stability through a feedback power monitoring detection module 3. The distributed vibration sensing channel uses a 1650nm light source with phase encoding, and ensures the integrity of the modulated signal through coherent detection by a phase modulator 6 after polarization optimization. The fiber optic grating monitoring channel uses a wavelength scanning narrow linewidth light source, and constructs a unidirectional optical path transmission system through a circulator. The three independently modulated optical signals are input into dedicated wavelength division multiplexers, and converged to a single main sensing fiber 13 via an optical fiber coupler 11. This fiber has a wavelength-selective grating array, i.e., an FBG array 14, etched inside, which can achieve directional reflection of the monitoring band and maintain high transmittance of the transmission band.

[0066] The optical signal separation process employs a physical layer decoupling design: the fiber optic grating reflected signal is transmitted in reverse along the incident optical path, and spatial isolation between the reflected and incident light is achieved by switching at the circulator port; the backscattered Rayleigh light generated by the main sensing fiber 13 is separated into wavelengths by the wavelength separation device 16, where the 1550nm band scattered light characterizes temperature distribution information, and the 1650nm band scattered light carries vibration modulation characteristics. Each wavelength channel is equipped with an independent detector for photoelectric conversion. The temperature channel, i.e., the DTS channel, uses a temperature-optimized detector to suppress thermal drift, and the vibration channel, i.e., the DVS channel, is equipped with a low-noise amplification link to improve the sensitivity of perturbation detection.

[0067] Signal collaborative processing achieves time-space dual-dimensional synchronization through edge demodulation device 19: time synchronization mechanism 20 integrates satellite time synchronization and network time synchronization as dual references, and completes timestamp alignment through programmable logic devices; data processing stream 21 implements multi-channel parallel analysis, temperature analysis module 28 analyzes the attenuation characteristics of scattering intensity with fiber length, vibration analysis module 29 demodulates the temporal perturbation mode of phase signal, and strain analysis module 30 tracks characteristic wavelength drift. Three-channel characteristic parameters are input into multi-parameter fusion model 22, and a joint decision is made on the three-channel characteristic parameters through an adaptive weighting algorithm. Anomaly decision engine 31 implements a hierarchical judgment strategy, combined with dynamic threshold adjustment and spatiotemporal correlation analysis, and then triggers multi-mode alarm output module 32 based on the fusion result. Multi-mode alarm output module 32 drives the on-site audible and visual alarm device through relay control 33, uploads equipment status data through industrial communication interface 34, and transmits positioning information to the central monitoring platform in real time through high-speed network channel 35.

[0068] Optical stability is achieved through a multi-layered protection mechanism: each laser is equipped with a precision temperature control module to suppress wavelength drift, the transmission optical path adopts a stress-relief packaging structure to reduce micro-bending loss, and optical isolators are set at key nodes to avoid reverse interference. The entire optical system achieves physical layer channel isolation through a wavelength allocation scheme, combined with optical component parameter matching design, to maintain the signal integrity of each channel under long-distance transmission conditions, providing basic optical protection for high-precision synchronous monitoring of multiple parameters.

[0069] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications and substitutions based on the technical solutions and inventive concepts provided by the present invention should be covered within the scope of protection of the present invention.

Claims

1. A fiber optic composite sensor array and edge demodulation device for multi-parameter monitoring of long-distance infrastructure, characterized in that, The fiber optic composite sensing array includes: A distributed temperature sensing channel is provided with a laser (1), an acousto-optic modulator (2) and a detection module (3). The acousto-optic modulator (2) generates controllable light pulses, and the detection module (3) performs pulse power monitoring and feedback adjustment. The laser (1) is connected to the acousto-optic modulator (2) through a polarization-maintaining fiber. The distributed vibration sensing channel is equipped with a laser (5), a phase modulator (6) and a detection module (7). The phase modulator (6) loads a highly complex encoding sequence, the detection module (7) verifies the integrity of the modulation signal, and the laser (5) enters the phase modulator (6) after polarization optimization. The fiber optic grating sensing channel is equipped with a laser (9), a tunable filter (10), and a circulator. The tunable filter (10) generates a wavelength scanning beam, and the circulator enables directional transmission of optical signals. The main sensing fiber (13) has an FBG array (14) inside, which selectively reflects specific wavelengths and maintains transmission of the transmission wavelength. The grating reflection signal returns to the circulator along the original transmission path, is input to the circulator port 2 and output to the circulator port 3, and is guided to the FBG detector (15). The wavelength division multiplexing component includes three independent wavelength division multiplexers: WDM1 port (4), WDM2 port (8) and WDM3 port (12) respectively receive three channel optical signals and are fed into a single main sensing fiber (13) through an optical fiber coupler (11). Wavelength separation device (16) demultiplexes the back Rayleigh scattered light and directs the different wavelength signals to DTS detector (17) and DVS detector (18) respectively. The digital system collects and processes all signals after photoelectric conversion; The edge demodulation device (19) includes: The time synchronization mechanism (20) includes a GPS receiver unit (23), a PTP precision clock protocol unit (24), and an FPGA timestamp alignment circuit (25). The data processing stream (21) is equipped with a signal acquisition unit (26) and a feature extraction unit (27) that work in parallel. The feature extraction unit (27) executes the temperature analysis module (28), the vibration analysis module (29) and the strain analysis module (30) in parallel. The multi-parameter fusion model (22) integrates temperature, vibration, and strain multi-dimensional information for joint processing and analysis and outputs decision instructions.

2. The fiber optic composite sensor array and edge demodulation device for multi-parameter monitoring of long-distance infrastructure according to claim 1, characterized in that: The multi-parameter fusion model (22) also includes an anomaly decision engine (31) and a multi-mode alarm output module (32). The anomaly decision engine (31) implements a hierarchical judgment strategy, combined with dynamic threshold adjustment and spatiotemporal correlation analysis. The multi-mode alarm output module (32) drives the on-site sound and light alarm device through relay control (33), uploads equipment status data through the industrial communication interface (34), and transmits positioning information to the central monitoring platform in real time through the high-speed network channel (35).

3. The fiber optic composite sensor array and edge demodulation device for multi-parameter monitoring of long-distance infrastructure according to claim 1, characterized in that: The FBG array (14) inside the main sensing fiber (13) is arranged in a regular pattern, and a set of grating units with characteristic reflection spectra is set at certain intervals.

4. The fiber optic composite sensor array and edge demodulation device for multi-parameter monitoring of long-distance infrastructure according to claim 1, characterized in that: The time synchronization mechanism (20) adopts a dual-path redundancy design architecture.

5. The fiber optic composite sensor array and edge demodulation device for multi-parameter monitoring of long-distance infrastructure according to claim 1, characterized in that: The GPS receiving unit (23) is used to obtain the absolute time reference provided by satellite positioning, the PTP precision clock protocol unit (24) is used to realize high-precision time synchronization in the network environment, and the FPGA timestamp alignment circuit (25) performs intelligent calibration and compensation on the two input time signals.

6. The fiber optic composite sensor array and edge demodulation device for multi-parameter monitoring of long-distance infrastructure according to claim 1, characterized in that: The temperature analysis module (28) is used to identify spatial temperature anomalies, the vibration analysis module (29) calculates energy distribution through frequency domain transformation, and the strain analysis module (30) performs window detection for dynamic baseline calibration.

7. The fiber optic composite sensor array and edge demodulation device for multi-parameter monitoring of long-distance infrastructure according to claim 1, characterized in that: The laser (1) is a distributed feedback laser with a wavelength of 1550nm.

8. The fiber optic composite sensor array and edge demodulation device for multi-parameter monitoring of long-distance infrastructure according to claim 1, characterized in that: The laser 2 (5) provides a 1650nm light source.

9. The fiber optic composite sensor array and edge demodulation device for multi-parameter monitoring of long-distance infrastructure according to claim 1, characterized in that: The entire optical transmission line employs a multi-stabilization design, ensuring wavelength characteristics stability through thermal management and mechanical protection.

Images