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CN-121994284-A - Multi-dimensional parameter sense fusion system based on multi-core optical fiber

CN121994284ACN 121994284 ACN121994284 ACN 121994284ACN-121994284-A

Abstract

The invention provides a multi-dimensional parameter general sense fusion system based on multi-core optical fibers, and relates to the technical field of optical fiber communication and optical fiber sensing. The system comprises a multi-core optical fiber, a first fan-in fan-out module, a second fan-out module and a multi-dimensional sensing signal acquisition device, wherein the multi-core optical fiber comprises two independent fiber cores, an input end and an output end of the first fan-in fan-out module respectively comprise two ports, the two ports of the input end are respectively connected with a communication signal sending unit and the multi-dimensional sensing signal acquisition device, the two ports of the output end are respectively connected with the two independent fiber cores of the multi-core optical fiber, the input end of the second fan-in fan-out module comprises two ports, the two ports are respectively connected with the two independent fiber cores of the multi-core optical fiber, and the output end is connected with a communication signal receiving unit. The invention realizes the integration of communication and sensing, and has high functional integration level and high resource utilization rate. The invention can be widely applied to various complex environments such as power communication networks, sea cables, comprehensive pipe racks, rail transit, oil and gas pipelines and the like.

Inventors

  • DONG YONGKANG
  • TANG XIAOHUI
  • Ba dexin
  • XIA MENG

Assignees

  • 哈尔滨工业大学

Dates

Publication Date
20260508
Application Date
20260123

Claims (10)

  1. 1. A multi-dimensional parameter through sensing fusion system based on multi-core optical fibers is characterized in that the system is used for simultaneously realizing sensing and communication in a single optical fiber, the system comprises the multi-core optical fiber (1), a first fan-in fan-out module (2), a second fan-in fan-out module (3) and a multi-dimensional sensing signal acquisition device (4), wherein the multi-core optical fiber (1) comprises at least two independent fiber cores, the input end of the first fan-in fan-out module (2) comprises at least two ports, the output end of the first fan-in fan-out module comprises at least two ports, one port of the input end of the first fan-in fan-out module (2) is connected with a communication signal sending unit (5), the other port of the input end of the first fan-in fan-out module (2) is connected with two independent fiber cores of the multi-core optical fiber (1), the two ports of the output end of the first fan-in fan-out module (2) are respectively connected with two independent fiber cores of the multi-core optical fiber (1), the input end of the second fan-in fan-out module (3) comprises at least two ports, the output end of the second fan-in fan-out module comprises at least one port, the two ports of the input end of the second fan-in fan-out module (3) are respectively connected with two independent fiber cores, and the two independent fiber cores of the multi-core (1) respectively, and the output end of the multi-in communication unit (6) is connected with the input end of the multi-core; The multidimensional sensing signal acquisition device (4) comprises a pulse modulation module (41), a first circulator (42), a data acquisition card (43), an OTDR detection module, a BOTDR detection module and a phi-OTDR detection module, wherein the pulse modulation module (41) is used for generating different types of light pulses, the light pulses are injected into an input port of a first fan-in fan-out module (2) through the first circulator (42), the OTDR detection module is used for measuring the intensity of a back Rayleigh scattering signal of an optical fiber, the BOTDR detection module is used for carrying out frequency shift detection on the Brillouin scattering signal of the optical fiber, the phi-OTDR detection module is used for carrying out coherent detection on the back Rayleigh scattering signal of the optical fiber, the OTDR detection module, the BOTDR detection module and the phi-OTDR detection module are respectively connected with the data acquisition card (43), and the data acquisition card (43) is used for acquiring the optical fiber sensing signal.
  2. 2. The multi-core fiber-based multi-dimensional parametric passband fusion system of claim 1, wherein the pulse modulation module (41) comprises a broadband light source (411), a first acousto-optic modulator (412), a wavelength division multiplexing beam combiner (413), a narrowband light source (414), a first optical coupler (415), a second acoustic light modulator (416), the OTDR detection module comprises an echo amplifier (441), a wavelength division multiplexing beam splitter (442), a detector (443), the BOTDR detection module comprises a second optical coupler (451), an electro-optic modulator (452), a polarization controller (453), a first four-port optical coupler (454), a first balanced detector (455), a first filtering detector (456), the Φ -OTDR detection module comprises a second four-port optical coupler (461), a second balanced detector (462), a second filtering detector (463), a fiber grating filter (464), and the multi-dimensional sensing signal acquisition device (4) further comprises a pulse amplifier (47) and a second circulator (48); The output end of the broadband light source (411) is connected with the input end of the first acousto-optic modulator (412), the output end of the first acousto-optic modulator (412) is connected with the input end of the wavelength division multiplexing beam combiner (413), the output end of the narrowband light source (414) is connected with the input end of the first optical coupler (415), the output end of the first optical coupler (415) is respectively connected with the input ends of the second optical modulator (416) and the second optical coupler (451), the output end of the second optical modulator (416) is connected with the input end of the wavelength division multiplexing beam combiner (413), the output end of the wavelength division multiplexing beam combiner (413) is connected with the input end of the pulse amplifier (47), the output end of the pulse amplifier (47) is connected with the first port of the first circulator (42), and the second port of the first circulator (42) is connected with the input end of the first fan-in module (2); The third port of the first circulator (42) is connected with the input end of the echo amplifier (441), the output end of the echo amplifier (441) is connected with the input end of the wavelength division multiplexing beam splitter (442), the output end of the wavelength division multiplexing beam splitter (442) is respectively connected with the input end of the detector (443) and the first port of the second circulator (48), and the output end of the detector (443) is connected with the data acquisition card (43); The output end of the electro-optical modulator (452) is connected with the input end of the polarization controller (453), the output end of the polarization controller (453) and the third port of the second circulator (48) are respectively connected with two ports of the input end of the first four-port optical coupler (454), the output end of the first four-port optical coupler (454) is connected with the input end of the first balance detector (455), the output end of the first balance detector (455) is connected with the input end of the first filter detector (456), and the output end of the first filter detector (456) is connected with the data acquisition card (43); The second port of the second circulator (48) is connected with the input end of a fiber bragg grating filter (464), the output end of the fiber bragg grating filter (464) is connected with the input end of a second four-port optical coupler (461), the output end of the second four-port optical coupler (461) is connected with the input end of a second balance detector (462), the output end of the second balance detector (462) is connected with the input end of a second filter detector (463), and the output end of the second filter detector (463) is connected with a data acquisition card (43).
  3. 3. The multi-core fiber-based multi-dimensional parametric fusion system according to claim 2, wherein the operation of the multi-dimensional sensing signal acquisition device (4) comprises: The broadband light source (411) sends out detection pulse light for optical time domain reflection measurement to the first acousto-optic modulator (412), the narrowband light source (414) sends out long pulse light for Brillouin distributed measurement and narrow pulse light for coherent Rayleigh distributed measurement to the first optical coupler (415), the first optical coupler (415) couples part of the light to the second acousto-optic modulator (416) and the other part of the light to the second optical coupler (451), the first acousto-optic modulator (412) and the second acousto-optic modulator (416) respectively modulate the pulse light, the modulated pulse light is input into the wavelength division multiplexing beam combiner (413) for beam combination, the pulse light after beam combination enters the pulse amplifier (47) for optical power amplification, and the amplified pulse light enters the first port of the first circulator (42) and is injected into the input port of the first fan-in fan-out module (2) through the second port of the first circulator (42); The back scattered light returned by the first fan-in fan-out module (2) enters an echo amplifier (441) through a third port of a first circulator (42) for echo amplification, then enters a wavelength division multiplexing beam splitter (442), a part of light separated by the wavelength division multiplexing beam splitter (442) enters a detector (443), the detector (443) is used for photoelectric conversion and intensity detection of the back Rayleigh scattered signal, and then enters a data acquisition card (43), the other part of light separated by the wavelength division multiplexing beam splitter (442) enters a first port of a second circulator (48), a second port and a third port of the second circulator (48) are respectively connected with a fiber grating filter (464) and a first four-port optical coupler (454), and the fiber grating filter (464) is used for wavelength selective filtering of the back scattered light; The second optical coupler (451) is used for coupling one part of light to the electro-optical modulator (452) and the other part of light to the input end of the second four-port optical coupler (461), wherein the electro-optical modulator (452) is used for modulating pulse light and then sending the pulse light to the polarization controller (453), and polarized light sent by the polarization controller (453) is sent to the input end of the first four-port optical coupler (454); The output end of the first four-port optical coupler (454) is connected with a first balance detector (455), the first balance detector 45 is used for photoelectric conversion, the output end of the first balance detector (455) is connected with a first filter detector (456), the first filter detector (456) is used for filtering and detecting, and the first filter detector (456) is connected with the data acquisition card (43); The output end of the second four-port optical coupler (461) is connected with a second filtering detector (463), the second filtering detector (463) is used for filtering and detecting, and the second filtering detector (463) is connected with the data acquisition card (43).
  4. 4. A multi-core fiber based multi-dimensional parametric fusion system according to claim 3, further comprising a signal fusion processing module connected to the data acquisition card (43) for processing the acquired signals, the signal fusion processing module comprising: the filtering and noise reduction unit is used for denoising and normalizing the collected optical fiber sensing signals; The signal characteristic extraction unit is used for extracting temperature, strain, vibration and attenuation characteristics corresponding to the optical fiber sensing signals; And the multi-parameter joint judging unit is used for comprehensively judging the state of the multi-core optical fiber (1) according to the characteristics of temperature, strain, vibration and attenuation.
  5. 5. The multi-fiber based multi-dimensional parametric fusion system of claim 1, wherein the first fan-in and fan-out module (2) and the second fan-in and fan-out module (3) are fiber splitters.
  6. 6. The multi-dimensional parametric passband fusion system based on multi-core optical fibers according to claim 2, wherein the broadband light source (411) is a super-radiation light emitting diode or a wide-spectrum ASE light source, the central wavelength range is 1525-1565 nm, the spectral bandwidth is not less than 30nm, the output light power range is 5-20 dBm, the narrow-band light source (414) is a narrow-line-width continuous laser, the central wavelength range is 1528-1565 nm, the line width is less than 100 kHz, and the output light power range is 10-20 dBm.
  7. 7. The multi-core fiber-based multi-dimensional parametric fusion system of claim 2, wherein the first optical coupler (415) has a split ratio of 4:1 and the second optical coupler (451) has a split ratio of 1:1.
  8. 8. The multi-core fiber based multi-dimensional parametric fusion system of claim 2, wherein the modulation bandwidth of the first acousto-optic modulator (412) and the second acousto-optic modulator (416) is not less than 80 MHz, the extinction ratio is not less than 40 dB, and the rise time is less than 10 ns.
  9. 9. The multi-core fiber-based multi-dimensional parametric fusion system according to claim 2, wherein the first four-port optical coupler (454) and the second four-port optical coupler (461) are 90 ° optical mixers or 2×4 optical couplers, the isolation degree of the first circulator (42) and the second circulator (48) is not less than 40 dB, and the insertion loss is less than 1 dB.
  10. 10. The multi-fiber based multi-dimensional parametric fusion system according to claim 2, wherein the pulse amplifier (47) and the echo amplifier (441) are erbium-doped fiber amplifiers, and the first filter detector (456) and the second filter detector (463) are bandpass or lowpass filters.

Description

Multi-dimensional parameter sense fusion system based on multi-core optical fiber Technical Field The invention relates to the technical field of optical fiber communication and optical fiber sensing, in particular to a multi-dimensional parameter sense fusion system based on multi-core optical fibers. Background Optical fibers are widely used as a core carrier for modern communication in power communication networks, submarine communication, data centers and urban communication systems. Most of the existing communication optical fibers adopt single-mode optical fibers, the main functions of the communication optical fibers are concentrated on information transmission, and the multi-parameter monitoring requirements of temperature, strain, vibration and the like are difficult to meet. When communication and state monitoring are required, it is usually necessary to additionally arrange independent sensing fibers, use other fiber cores or install additional sensors, which not only occupies fiber resources, but also increases system construction and operation and maintenance costs. Multicore fibers are a type of optical fiber that contains multiple individual cores in a common cladding. The design of the optical fiber enables a single optical fiber to have higher functional integration level, not only can the communication capacity in unit sectional area be improved through parallel fiber cores, but also a novel transmission mode can be realized by utilizing the optical wave coupling effect between adjacent fiber cores under certain conditions. The multi-core optical fiber can simultaneously transmit a plurality of signals, effectively reduces the number of optical cables and the wiring complexity, reduces the construction cost, and has the characteristics of high bandwidth, high speed and certain fault tolerance. At present, the multi-core optical fiber is mainly applied to short-distance high-capacity data transmission scenes, such as local area networks and data centers, and is also widely applied to the fields of medical fields (such as endoscopic diagnosis), aerospace (such as intelligent skins), building health monitoring, optical fiber gyro rings and the like. These applications fully represent the advantages of high integration, flexibility and multi-fiber fusion. In the field of distributed optical fiber sensing, brillouin scattering can be used for long-distance temperature and strain monitoring, rayleigh scattering can be used for high-resolution vibration and impact monitoring, and optical power attenuation monitoring can be used for line loss and breakpoint positioning. However, most of the prior art relies on a single scattering mechanism to provide only part of the parametric information. Under complex scenes such as comprehensive pipe racks, subway tunnels, suspended sea cables, oil and gas pipeline leakage or rail traffic safety, the running state is difficult to accurately judge by means of a single monitoring means, and the joint perception of multidimensional parameters is needed. Most of the existing multidimensional sensing schemes need to additionally arrange independent optical fibers, so that the resource utilization rate is low, the operation and maintenance cost is high, and the large-scale popularization is difficult. On the premise of not influencing communication performance, the multi-core optical fiber is utilized to realize the fusion of communication and multi-dimensional scattering mechanisms such as Brillouin scattering, rayleigh scattering, attenuation scattering and the like, and the joint monitoring of temperature, strain, vibration and optical fiber health state is a key problem to be solved in the prior art. However, even if the multi-core optical fiber is adopted in the prior art, a plurality of fiber cores are still required to be occupied, and the integration level is not maximized. It is desirable to achieve both high speed communication and multi-dimensional sensing within a single core. This faces significant challenges such as noise crosstalk between the communication light and the high power sensing pulse light, contradictory requirements of different sensing mechanisms (e.g. brillouin scattering and rayleigh scattering) on the light source parameters (line width, power, pulse width), and rational arrangement of the up/down signals. At present, no mature scheme can stably and efficiently complete the communication and the sensing functions of all dimensions in one fiber core. Disclosure of Invention In order to solve or alleviate one or more of the above-mentioned problems, the present invention proposes a multi-dimensional parametric sense fusion system based on multi-core optical fibers. The multi-dimensional parameter general sensing fusion system based on the multi-core optical fiber is used for simultaneously realizing sensing and communication in a single optical fiber and comprises the multi-core optical fiber, a first fan-in fan-out module, a second fan-