Optical signal processing equipment integrating BOTDR (Brillouin Optical Time Domain Reflectometer) and phi-OTDR functions

Abstract

The utility model relates to the technical field of optical fiber sensing, and discloses optical signal processing equipment integrating functions of a BOTDR (Brillouin Optical Time Domain Reflectometer) and a phi-OTDR (Phi-Optical Time Domain Reflectometer), which is used for simultaneously measuring vibration, temperature and stress by using one kind of equipment. The optical signal processing equipment integrating the BOTDR and phi-OTDR functions comprises a laser generator, a first coupler, an optical signal processing module and a second coupler which are connected in sequence, and the optical signal processing module is further used for being connected with an optical fiber to be tested, transmitting pulse light to the optical fiber to be tested and receiving scattered light which is returned by the optical fiber to be tested and contains test information. The second coupler is respectively connected with the first optical filter and the second optical filter, the first optical filter and the second optical filter are respectively used for receiving a first path of scattered light and a second path of scattered light sent by the second coupler, the first path of scattered light is used for vibration testing, and the second path of scattered light is used for temperature and stress testing; and the first optical filter and the second optical filter are respectively connected with the photoelectric conversion module.

Description

Technical Field

[0001] This utility model relates to the field of fiber optic sensing technology, and in particular to an optical signal processing device that integrates BOTDR and φ-OTDR functions. Background Technology

[0002] Existing phase-sensitive optical time-domain reflectometry (φ-OTDR) and Brillouin optical time-domain reflectometry (BOTDR) have limited functions. φ-OTDR is limited to vibration monitoring, while BOTDR is limited to temperature and stress measurement. This means that in scenarios where these parameters need to be measured simultaneously, two devices need to be deployed, which not only increases costs and occupies more fiber optic resources, but also increases the difficulty of data processing. Utility Model Content

[0003] The main purpose of this invention is to solve the technical problem that existing technologies cannot simultaneously measure vibration, temperature and stress using a single device.

[0004] The first aspect of this utility model provides an optical signal processing device integrating BOTDR and φ-OTDR functions, comprising: a laser generator; a first coupler, the input end of which is connected to the output end of the laser generator; an optical signal processing module, the input end of which is connected to the first output end of the first coupler; a first transmission end of the optical signal processing module for connecting to an optical fiber under test, transmitting pulsed light to the optical fiber under test, and receiving scattered light containing test information returned by the optical fiber under test; a second coupler, the input end of which is connected to the output end of the optical signal processing module; a first optical filter, the input end of which is connected to the first output end of the second coupler, for receiving a first path of scattered light sent by the second coupler, the first path of scattered light being used for vibration testing; a second optical filter, the input end of which is connected to the second output end of the second coupler, for receiving a second path of scattered light sent by the second coupler, the second path of scattered light being used for temperature and stress testing; and a photoelectric conversion module, the first photoelectric conversion input end of which is connected to the second output end of the first coupler, the second photoelectric conversion input end of which is connected to the output end of the first optical filter, the third photoelectric conversion input end of which is connected to the third output end of the first coupler, and the fourth photoelectric conversion input end of which is connected to the output end of the second optical filter.

[0005] In one feasible implementation, the laser generator is a narrow linewidth laser or a wavelength tunable laser.

[0006] In one feasible implementation, the optical signal processing module includes an optical signal processing unit and a circulator. The input terminal of the optical signal processing unit is connected to the first output terminal of the first coupler, the output terminal of the optical signal processing unit is connected to the input terminal of the circulator, the circulator is connected to the optical fiber under test through the first transmission terminal, and the output terminal of the circulator is connected to the input terminal of the second coupler.

[0007] In one feasible implementation, the optical signal processing unit includes a semiconductor optical amplifier, a first amplifier, and a third optical filter, wherein the semiconductor optical amplifier, the first amplifier, and the third optical filter are connected in sequence, the first input terminal of the semiconductor optical amplifier is connected to the first output terminal of the first coupler, and the output terminal of the third optical filter is connected to the input terminal of the circulator.

[0008] In one feasible implementation, the optical signal processing module further includes a second amplifier, the input of which is connected to the output of the circulator, and the output of which is connected to the input of the second coupler.

[0009] In one feasible implementation, the photoelectric conversion module includes a first photoelectric converter and a second photoelectric converter. The first photoelectric converter is connected to the second output terminal of the first coupler through the first photoelectric conversion input terminal and to the output terminal of the first optical filter through the second photoelectric conversion input terminal. The second photoelectric converter is connected to the third output terminal of the first coupler through the third photoelectric conversion input terminal and to the output terminal of the second optical filter through the fourth photoelectric conversion input terminal.

[0010] In one feasible implementation, the device further includes a signal acquisition and processing module, wherein a first input terminal of the signal acquisition and processing module is connected to the first photoelectric converter via a first photoelectric conversion output terminal, and a second input terminal is connected to the second photoelectric converter via a second photoelectric conversion output terminal.

[0011] In one feasible implementation, the output terminal of the signal acquisition and processing module is connected to the second input terminal of the semiconductor optical amplifier.

[0012] In one feasible implementation, the device further includes a polarization controller, the input of which is connected to the output of the laser generator, and the output of which is connected to the input of the first coupler.

[0013] In one feasible implementation, the first amplifier is an erbium-doped fiber amplifier.

[0014] The technical solution provided by this utility model includes an optical signal processing device integrating BOTDR and φ-OTDR functions, comprising: a laser generator; a first coupler, the input of which is connected to the output of the laser generator; an optical signal processing module, the input of which is connected to the first output of the first coupler; a first transmission end of the optical signal processing module for connecting to the optical fiber under test, transmitting pulsed light to the optical fiber under test, and receiving scattered light containing test information returned by the optical fiber under test; a second coupler, the input of which is connected to the output of the optical signal processing module; a first optical filter, the input of which is connected to the first output of the second coupler, for receiving a first path of scattered light sent by the second coupler, the first path of scattered light being used for vibration testing; a second optical filter, the input of which is connected to the second output of the second coupler, for receiving a second path of scattered light sent by the second coupler, the second path of scattered light being used for temperature and stress testing; and a photoelectric conversion module, the first photoelectric conversion input of which is connected to the second output of the first coupler, the second photoelectric conversion input of which is connected to the output of the first optical filter, the third photoelectric conversion input of which is connected to the third output of the first coupler, and the fourth photoelectric conversion input of which is connected to the output of the second optical filter. In this embodiment of the invention, the optical signal processing device integrates a laser generator, a coupler, an optical signal processing module, an optical filter, and a photoelectric conversion module, enabling simultaneous measurement of vibration, temperature, and stress. This significantly reduces testing costs, simplifies equipment deployment and maintenance, effectively saves fiber optic resources, and provides efficient data integration and analysis capabilities, thereby improving overall testing efficiency and accuracy. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of an embodiment of an optical signal processing device integrating BOTDR and φ-OTDR functions according to the present invention;

[0016] Figure 2 This is a schematic diagram of another embodiment of the optical signal processing device that integrates BOTDR and φ-OTDR functions in this utility model. Detailed Implementation

[0017] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0018] In this application, unless otherwise specified or limited, the terms "connection" and "fixation" should be understood in a broad sense. For example, "fixation" can mean fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. For those skilled in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0019] In addition, the descriptions of "first", "second", etc. in this application are for descriptive purposes only and should not be understood as indicating or implying their relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0020] This invention proposes an optical signal processing device that integrates BOTDR and φ-OTDR functions. Please refer to [link / reference]. Figure 1 The optical signal processing device 100, which integrates BOTDR and φ-OTDR functions, includes a laser generator 10, a first coupler 20, an optical signal processing module 30, a second coupler 40, a first optical filter 50, a second optical filter 60, and a photoelectric conversion module 70.

[0021] The output of laser generator 10 is connected to the input of first coupler 20. The first output of first coupler 20 is connected to the input of optical signal processing module 30, the second output is connected to the first photoelectric conversion input of photoelectric conversion module 70, and the third output is connected to the third photoelectric conversion input of photoelectric conversion module 70. The output of optical signal processing module 30 is connected to the input of second coupler 40. Optical signal processing module 30 also includes a first transmission end, which is connected to the optical fiber under test (ODT) to transmit pulsed light to the ODT and receive scattered light containing test information returned by the ODT. The second coupler... The first output terminal of the device 40 is connected to the input terminal of the first optical filter 50, and the second output terminal is connected to the input terminal of the second optical filter 60. The first optical filter 50 is used to receive the first path of scattered light sent by the second coupler 40. The first path of scattered light is used for vibration testing. The second optical filter 60 is used to receive the second path of scattered light sent by the second coupler 40. The second path of scattered light is used for temperature and stress testing. The output terminal of the first optical filter 50 is connected to the second photoelectric conversion input terminal of the photoelectric conversion module 70, and the output terminal of the second optical filter 60 is connected to the fourth photoelectric conversion input terminal of the photoelectric conversion module 70.

[0022] The laser generator 10 serves as a light source, providing the necessary laser light for the entire optical signal processing device 100. After passing through components such as couplers and optical signal processing modules, these lasers are used for applications such as vibration testing, temperature and stress testing.

[0023] The first coupler 20 receives the laser output from the laser generator 10 and splits it into three paths. One path is transmitted to the optical signal processing module 30, and the other two paths are transmitted to the photoelectric conversion module 70, so that the original signal and the processed signal can be monitored simultaneously.

[0024] The optical signal processing module 30 receives a laser beam transmitted from the first coupler 20, transmits the laser beam to the optical fiber under test, receives the scattered light returned by the optical fiber under test, and sends the scattered light to the second coupler 40.

[0025] The second coupler 40 receives the scattered light transmitted by the optical signal processing module 30 and splits it into two paths, which are sent to the first optical filter 50 and the second optical filter 60 respectively.

[0026] The first optical filter 50 includes a first filtering channel, which filters out scattered light suitable for vibration measurement according to a first specific frequency or wavelength range. The second optical filter 60 includes a second filtering channel, which filters out scattered light suitable for temperature and stress changes according to a second specific frequency or wavelength, thereby realizing simultaneous monitoring of multiple parameters.

[0027] The photoelectric conversion module 70 receives two additional laser beams from the first coupler 20, as well as two scattered beams from the first optical filter 50 and the second optical filter 60.

[0028] During operation, the laser emitted by the laser generator 10 is split into three paths by the first coupler 20. Two of these paths are directly input to the photoelectric conversion module 70 as reference signals, while the other path enters the optical signal processing module 30 for preprocessing. The processed pulsed light is then sent to the optical fiber under test and the scattered light containing test information returned by the optical fiber under test is received. This scattered light is split into two paths again by the second coupler 40 and filtered through different channels of the first optical filter 50 and the second optical filter 60, respectively. Finally, it is converted into an electrical signal by the photoelectric conversion module 70. These electrical signals can be further acquired, amplified, and digitized to extract information on parameters such as vibration, temperature, and stress.

[0029] In this embodiment of the invention, the optical signal processing device integrating BOTDR and φ-OTDR functions achieves simultaneous measurement of vibration, temperature and stress by integrating a laser generator, coupler, optical signal processing module, optical filter and photoelectric conversion module. This not only reduces costs and simplifies installation, but also saves fiber optic resources and provides convenience for data integration and analysis.

[0030] Please see Figure 2 Another embodiment of the optical signal processing device integrating BOTDR and φ-OTDR functions in this utility model includes:

[0031] The optical signal processing device 100 integrating BOTDR and φ-OTDR functions includes a laser generator 10, a first coupler 20, an optical signal processing module 30, a second coupler 40, a first optical filter 50, a second optical filter 60, a photoelectric conversion module 70, a polarization controller 80, and a signal acquisition and processing module 90.

[0032] The output of laser generator 10 is connected to the input of polarization controller 80. The output of polarization controller 80 is connected to the input of first coupler 20. The first output of first coupler 20 is connected to the input of optical signal processing module 30. The second and third outputs are connected to the first and third photoelectric conversion inputs of photoelectric conversion module 70, respectively. The output of optical signal processing module 30 is connected to the input of second coupler 40. Optical signal processing module 30 is also connected to the optical fiber under test (ODT) via a first transmission terminal, transmitting pulsed light to the ODT and receiving scattered light containing test information returned by the ODT. The first output of second coupler 40 is connected to the input of first optical filter 50. The second output terminal of the second coupler 40 is connected to the input terminal of the second optical filter 60, which is used to receive the first scattered light transmitted by the second coupler 40. The second scattered light is used for vibration testing. The second output terminal of the second coupler 40 is connected to the input terminal of the second optical filter 60, which is used to receive the second scattered light transmitted by the second coupler 40. The second scattered light is used for temperature and stress testing. The output terminal of the first optical filter 50 is connected to the second photoelectric conversion input terminal of the photoelectric conversion module 70. The output terminal of the second optical filter 60 is connected to the fourth photoelectric conversion input terminal of the photoelectric conversion module 70. The first photoelectric conversion output terminal of the photoelectric conversion module 70 is connected to the first input terminal of the signal acquisition and processing module 90, and the second photoelectric conversion output terminal is connected to the second input terminal of the signal acquisition and processing module 90.

[0033] The laser generator 10 can be a narrow linewidth laser or a wavelength tunable laser. Narrow linewidth lasers help reduce the spectral width of the optical signal and improve measurement accuracy, while wavelength tunable lasers can flexibly adjust the output wavelength to meet the needs of various application scenarios and improve the flexibility and adaptability of the equipment.

[0034] The optical signal processing module 30 includes an optical signal processing unit 301 and a circulator 302. The input end of the optical signal processing unit 301 is connected to the first output end of the first coupler 20, and the output end is connected to the input end of the circulator 302. The circulator 302 is connected to the optical fiber under test through the first transmission end, and the output end of the circulator 302 is connected to the input end of the second coupler 40.

[0035] The optical signal processing module 30 also includes a second amplifier 303, the input of which is connected to the output of the circulator 302, and the output of which is connected to the input of the second coupler 40.

[0036] The optical signal processing module 30 also includes an optical isolator 304. The input terminal of the optical isolator 304 is connected to the output terminal of the second amplifier 303, and the output terminal of the optical isolator 304 is connected to the input terminal of the second coupler 40. This is used to prevent reflected light generated during the transmission of the optical signal from interfering with the system and to ensure stable transmission of the optical signal.

[0037] The optical signal processing unit 301 includes a semiconductor optical amplifier (SOA) 3011, a first amplifier 3012, and a third optical filter 3013. The first input terminal of the semiconductor optical amplifier 3011 is connected to the first output terminal of the first coupler 20, and the second input terminal is connected to the output terminal of the signal acquisition and processing module 90. The output terminal of the semiconductor optical amplifier 3011 is connected to the input terminal of the first amplifier 3012, the output terminal of the first amplifier 3012 is connected to the input terminal of the third optical filter 3013, and the output terminal of the third optical filter 3013 is connected to the input terminal of the circulator 302. The first amplifier 3012 can be an erbium-doped fiber amplifier or a ytterbium-doped fiber amplifier.

[0038] The optical signal processing unit 301 also includes a tunable attenuator 3014. The input terminal of the tunable attenuator 3014 is connected to the output terminal of the semiconductor optical amplifier 3011, and the output terminal of the tunable attenuator 3014 is connected to the input terminal of the first amplifier 3012. It is used to adjust the optical signal intensity, thereby optimizing the amplification effect of the optical signal.

[0039] Both the first optical filter 50 and the second optical filter 60 are tunable filters with tunable center wavelength and bandwidth, allowing users to select the optimal filtering parameters according to the wavelength range of the optical signal under test, thereby improving the flexibility and applicability of the optical signal processing equipment. Both the first optical filter 501 and the second optical filter 502 adopt high-performance interference filter structures with high transmittance, low loss and high stability, to ensure that the optical signal received from the second coupler 40 can pass through the filter efficiently and reduce the loss of the optical signal during the filtering process. The first optical filter 50 and the second optical filter 60 also each include a temperature control circuit, which is used to monitor and control the operating temperature of the filter to compensate for the influence of temperature changes on the filter performance, thereby ensuring the measurement accuracy of the optical signal processing equipment under different temperature environments.

[0040] The photoelectric conversion module 70 includes a first photoelectric converter 701 and a second photoelectric converter 702. The first photoelectric converter 701 is connected to the second output terminal of the first coupler 20 through a first photoelectric conversion input terminal and to the output terminal of the first optical filter 50 through a second photoelectric conversion input terminal. The second photoelectric converter 702 is connected to the third output terminal of the first coupler 20 through a third photoelectric conversion input terminal and to the output terminal of the second optical filter 60 through a fourth photoelectric conversion input terminal. Both the first photoelectric converter 701 and the second photoelectric converter 702 include a high-sensitivity photodiode. The high-sensitivity photodiode has the characteristics of low dark current and high quantum efficiency to improve the conversion efficiency of the optical signal received from the first optical filter 50 and the second optical filter 60, thereby ensuring the measurement accuracy of the optical signal processing equipment under low light intensity conditions. The first photoelectric converter 701 and the second photoelectric converter 702 also each include a temperature compensation circuit. The temperature compensation circuit is used to monitor the operating temperature of the photoelectric converter and adjust its operating parameters according to temperature changes to compensate for the impact of temperature changes on photoelectric conversion efficiency and signal stability, thereby ensuring the measurement accuracy of the optical signal processing equipment under different temperature environments.

[0041] The first input terminal of the signal acquisition and processing module 90 is connected to the first photoelectric converter 701 through the first photoelectric conversion output terminal, and the second input terminal is connected to the second photoelectric converter 702 through the second photoelectric conversion output terminal, so as to acquire the electrical signal converted by the photoelectric conversion module 70 and process and analyze it. At the same time, the output terminal of the signal acquisition and processing module 90 is connected to the second input terminal of the semiconductor optical amplifier 3011 to monitor the output signal of the semiconductor optical amplifier 3011 in real time, detect its changes in a timely manner, and calibrate the equipment as needed to ensure the accuracy and stability of the measurement results.

[0042] During operation, the laser emitted by the laser generator 10 undergoes polarization state adjustment by the polarization controller 70, and then enters the first coupler 20 where it is split into three beams. The first beam is transmitted to the SOA 3011, the second beam is transmitted to the first photoelectric converter 701 as its local oscillator, and the third beam is transmitted to the second photoelectric converter 702 as its local oscillator. The SOA 3011 converts the continuous light into pulsed light. The pulsed light is then adjusted by the tunable attenuator 3014 and amplified by the first amplifier 3012. After being filtered by the third optical filter 3013, it enters the circulator 302 and is then output to the fiber under test. The scattered light from the fiber under test returns to the circulator 302, and the scattered light from the circulator 302 is then amplified by the second amplifier 303. After amplification, the light is transmitted by optical isolator 304 to the second coupler 40 and split into two scattered beams. The first scattered beam is transmitted to the first optical filter 50 and is used to test vibration, thus forming a φ-OTDR device. The second scattered beam is transmitted to the second optical filter 60 and is used to measure temperature and stress, thus forming a BOTDR device. The first optical filter 50 transmits the first scattered beam to the first photoelectric converter 701, and the second optical filter 60 transmits the second scattered beam to the second photoelectric converter 702. The second laser beam and the first scattered beam are transmitted to the signal acquisition and processing module 90 for processing after passing through the first photoelectric converter 701. The third laser beam and the second scattered beam are transmitted to the signal acquisition and processing module 90 for processing after passing through the second photoelectric converter 702.

[0043] In this embodiment of the invention, the optical signal processing device integrating BOTDR and φ-OTDR functions integrates a laser generator, a multi-stage coupler, an optical signal processing module, an optical filter, a photoelectric conversion module, and a signal acquisition and processing module, and can be optionally equipped with a polarization controller. This enables simultaneous high-precision measurement of vibration, temperature, and stress, which not only optimizes the optical path design and improves the flexibility and accuracy of signal processing, but also significantly enhances the overall performance of the device.

[0044] The above-described embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. An optical signal processing device integrating BOTDR and φ-OTDR functions, characterized in that, The device includes: Laser generator; A first coupler, the input of which is connected to the output of the laser generator; An optical signal processing module has its input end connected to the first output end of the first coupler; the first transmission end of the optical signal processing module is used to connect to the optical fiber under test, transmit pulse light to the optical fiber under test, and receive scattered light containing test information returned by the optical fiber under test. The second coupler has its input end connected to the output end of the optical signal processing module; The first optical filter has its input end connected to the first output end of the second coupler and is used to receive the first path of scattered light sent by the second coupler. The first path of scattered light is used for vibration testing. The second optical filter has its input end connected to the second output end of the second coupler and is used to receive the second path of scattered light sent by the second coupler. The second path of scattered light is used for temperature and stress testing. The photoelectric conversion module has a first photoelectric conversion input terminal connected to the second output terminal of the first coupler, a second photoelectric conversion input terminal connected to the output terminal of the first optical filter, a third photoelectric conversion input terminal connected to the third output terminal of the first coupler, and a fourth photoelectric conversion input terminal connected to the output terminal of the second optical filter.

2. The optical signal processing device integrating BOTDR and φ-OTDR functions according to claim 1, characterized in that, The laser generator is a narrow linewidth laser or a wavelength tunable laser.

3. The optical signal processing device integrating BOTDR and φ-OTDR functions according to claim 1, characterized in that, The optical signal processing module includes an optical signal processing unit and a circulator. The input end of the optical signal processing unit is connected to the first output end of the first coupler, the output end of the optical signal processing unit is connected to the input end of the circulator, the circulator is connected to the optical fiber under test through the first transmission end, and the output end of the circulator is connected to the input end of the second coupler.

4. The optical signal processing device integrating BOTDR and φ-OTDR functions according to claim 3, characterized in that, The optical signal processing unit includes a semiconductor optical amplifier, a first amplifier, and a third optical filter. The semiconductor optical amplifier, the first amplifier, and the third optical filter are connected in sequence. The first input terminal of the semiconductor optical amplifier is connected to the first output terminal of the first coupler, and the output terminal of the third optical filter is connected to the input terminal of the circulator.

5. The optical signal processing device integrating BOTDR and φ-OTDR functions according to claim 4, characterized in that, The optical signal processing module further includes a second amplifier, the input of which is connected to the output of the circulator, and the output of which is connected to the input of the second coupler.

6. The optical signal processing device integrating BOTDR and φ-OTDR functions according to claim 5, characterized in that, The photoelectric conversion module includes a first photoelectric converter and a second photoelectric converter. The first photoelectric converter is connected to the second output terminal of the first coupler through the first photoelectric conversion input terminal and to the output terminal of the first optical filter through the second photoelectric conversion input terminal. The second photoelectric converter is connected to the third output terminal of the first coupler through the third photoelectric conversion input terminal and to the output terminal of the second optical filter through the fourth photoelectric conversion input terminal.

7. The optical signal processing device integrating BOTDR and φ-OTDR functions according to claim 6, characterized in that, The device further includes a signal acquisition and processing module, wherein the first input terminal of the signal acquisition and processing module is connected to the first photoelectric converter through a first photoelectric conversion output terminal, and the second input terminal is connected to the second photoelectric converter through a second photoelectric conversion output terminal.

8. The optical signal processing device integrating BOTDR and φ-OTDR functions according to claim 7, characterized in that, The output terminal of the signal acquisition and processing module is connected to the second input terminal of the semiconductor optical amplifier.

9. The optical signal processing device integrating BOTDR and φ-OTDR functions according to any one of claims 1-8, characterized in that, The device also includes a polarization controller, the input of which is connected to the output of the laser generator, and the output of which is connected to the input of the first coupler.

10. The optical signal processing device integrating BOTDR and φ-OTDR functions according to any one of claims 4-8, characterized in that, The first amplifier is an erbium-doped fiber amplifier.

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