Signal processing device fusing DAS and BOTDR

Abstract

The utility model relates to the technical field of optical fiber sensing, in particular to a signal processing device integrating DAS and BOTDR, which comprises a signal transmitting module, a signal frequency shift module, a signal transmission module, a BOTDR optical signal processing module, a DAS optical signal processing module and a signal processing module. The signal emission module respectively emits continuous optical signals to the signal frequency shift module, the BOTDR and the DAS optical signal processing module through three output ends; the signal frequency shift module converts the continuous optical signal into linear frequency sweep pulse light; the signal transmission module outputs linear frequency sweeping pulse light to the optical fiber to be measured and collects scattered light, the scattered light is transmitted to the two optical signal processing modules to be processed, and processed signals are transmitted to the signal processing module to be analyzed. Compared with the prior art, the continuous light emitted to the optical fiber to be measured is converted into the linear sweep frequency pulse light, so that returned scattered light can be effectively separated, and vibration, temperature and stress can be monitored at the same time.

Description

Technical Field

[0001] This utility model relates to the field of fiber optic sensing technology, and more specifically, to a signal processing device that integrates DAS and BOTDR. Background Technology

[0002] Existing DAS (Distributed Acoustic Sensing) and BOTDR (Brillouin Optical Time Domain Reflectometry) devices can only perform individual functions. For example, DAS devices can only support vibration and sound monitoring, while BOTDR devices can only support temperature and stress measurement. This means that in scenarios where vibration, temperature, and stress need to be measured simultaneously, two devices need to be deployed at the same time, and the two devices need to work alternately and cannot be connected to the same fiber core to achieve simultaneous monitoring. Utility Model Content

[0003] The present invention aims to overcome at least one of the defects (deficiencies) of the prior art and provide a signal processing device that integrates DAS and BOTDR, and simultaneously monitors vibration, temperature and stress through a single optical fiber.

[0004] The technical solution adopted by this utility model is as follows:

[0005] This utility model provides a signal processing device that integrates DAS and BOTDR. The device includes a signal transmission module, a signal frequency shifting module, a signal transmission module, a BOTDR optical signal processing module, a DAS optical signal processing module, and a signal processing module.

[0006] The first output terminal of the signal transmitting module is connected to the first input terminal of the signal frequency shifting module, the second output terminal of the signal transmitting module is connected to the first input terminal of the BOTDR optical signal processing module, and the third output terminal of the signal transmitting module is connected to the first input terminal of the DAS optical signal processing module; the signal transmitting module transmits continuous optical signals through the first output terminal, the second output terminal, and the third output terminal respectively.

[0007] The output terminal of the signal frequency shifting module is connected to the input terminal of the signal transmission module, and the second input terminal of the signal frequency shifting module is connected to the output terminal of the signal processing module. The signal frequency shifting module is used to receive continuous optical signals and convert them into linear sweeping pulse light for output.

[0008] The first output terminal of the signal transmission module is used to connect to the optical fiber under test, the second output terminal of the signal transmission module is connected to the second input terminal of the BOTDR optical signal processing module, and the third output terminal of the signal transmission module is connected to the second input terminal of the DAS optical signal processing module; the signal transmission module is used to output linearly swept frequency pulse light to the optical fiber under test, and to acquire and output the scattered light returned by the optical fiber under test.

[0009] The output terminal of the BOTDR optical signal processing module is connected to the first input terminal of the signal processing module, and the output terminal of the DAS optical signal processing module is connected to the second input terminal of the signal processing module.

[0010] Optionally, the signal frequency shifting module includes an acousto-optic frequency shifter, a power amplifier, and a direct digital synthesizer;

[0011] The first input terminal of the acousto-optic frequency shifter is connected to the first output terminal of the signal transmitting module, and the output terminal of the acousto-optic frequency shifter is connected to the input terminal of the signal transmitting module.

[0012] The output terminal of the power amplifier is connected to the second input terminal of the acousto-optic frequency shifter, and the input terminal of the power amplifier is connected to the output terminal of the direct digital synthesizer; the input terminal of the direct digital synthesizer is connected to the output terminal of the signal processing module.

[0013] Optionally, the microwave amplification assembly includes a microwave low-noise amplifier, a microwave bandpass filter, a microwave downconversion circuit, an intermediate frequency bandpass filter, an intermediate frequency amplifier, and a first variable gain amplifier connected in sequence.

[0014] The input terminal of the microwave low-noise amplifier is connected to the output terminal of the microwave balun, and the output terminal of the first variable gain amplifier is connected to the first input terminal of the signal processing module.

[0015] Optionally, the DAS optical signal processing module includes a second balanced detector, an RF balun, and an RF amplification assembly;

[0016] The first input terminal of the second balanced detector is connected to the third output terminal of the signal transmitting module, and the second input terminal of the second balanced detector is connected to the third output terminal of the signal transmitting module;

[0017] The first input terminal of the radio frequency balun is connected to the first output terminal of the second balanced detector, the second input terminal of the radio frequency balun is connected to the second output terminal of the second balanced detector, and the output terminal of the radio frequency balun is connected to the input terminal of the radio frequency amplification component.

[0018] The output terminal of the radio frequency amplification component is connected to the second input terminal of the signal processing module.

[0019] Optionally, the radio frequency amplification assembly includes a radio frequency low noise amplifier, a radio frequency bandpass filter, and a second variable gain amplifier connected in sequence.

[0020] The input terminal of the RF low-noise amplifier is connected to the output terminal of the RF balun, and the output terminal of the second variable gain amplifier is connected to the second input terminal of the signal processing module.

[0021] Optionally, the signal processing module includes an analog-to-digital converter and a signal processing unit;

[0022] The first input terminal of the analog-to-digital converter is connected to the output terminal of the BOTDR optical signal processing module, the second input terminal of the analog-to-digital converter is connected to the output terminal of the DAS optical signal processing module, the output terminal of the analog-to-digital converter is connected to the input terminal of the signal processing unit, and the output terminal of the signal processing unit is connected to the second input terminal of the signal frequency shifting module.

[0023] Optionally, the signal transmitting module includes a laser transmitting unit and a first coupler;

[0024] The laser emitting unit is used to emit continuous optical signals. The output end of the laser emitting unit is connected to the input end of the first coupler. The first output end of the first coupler is connected to the first input end of the signal frequency shifting module. The second output end of the first coupler is connected to the first input end of the BOTDR optical signal processing module. The third output end of the first coupler is connected to the first input end of the DAS optical signal processing module.

[0025] Optionally, the signal transmission module includes a circulator, a first optical amplification component, and a second optical amplification component;

[0026] The input terminal of the first optical amplification component is connected to the output terminal of the signal frequency shifting module, the output terminal of the first optical amplification component is connected to the first transmission terminal of the circulator, the second transmission terminal of the circulator is used to connect to the optical fiber under test, the third transmission terminal of the circulator is connected to the input terminal of the second optical amplification component, the first output terminal of the second optical amplification component is connected to the second input terminal of the BOTDR optical signal processing module, and the second output terminal of the second optical amplification component is connected to the second input terminal of the DAS optical signal processing module.

[0027] Optionally, the first optical amplification component includes a first erbium-doped fiber amplifier and a first optical filter connected in sequence. The input end of the first erbium-doped fiber amplifier is connected to the output end of the signal frequency shifting module, and the output end of the first optical filter is connected to the first transmission end of the circulator.

[0028] The second optical amplification component includes a second erbium-doped fiber amplifier, a second optical filter, and a second coupler connected in sequence; the input end of the second erbium-doped fiber amplifier is connected to the third transmission end of the circulator, the first output end of the second coupler is connected to the second input end of the BOTDR optical signal processing module, and the second output end of the second coupler is connected to the second input end of the DAS optical signal processing module.

[0029] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0030] This invention utilizes a signal frequency shifting module to shift the frequency of a continuous optical signal emitted by a signal transmitting module. The frequency-shifted optical signal is then transmitted to the optical fiber under test via a signal transmission module. The optical signal propagates in the optical fiber and returns as scattered light. Because the incident optical signal has undergone frequency shifting, the different returned scattered light exhibits different frequency shift misalignments. This allows the BOTDR optical signal processing module and the DAS optical signal processing module to capture the corresponding Brillouin and Rayleigh scattered light for different frequency shift misalignments and continuous optical signals, effectively achieving the separation and processing of scattered light. This enables the signal processing module to simultaneously monitor vibration, temperature, and stress based on the separated Brillouin and Rayleigh scattered light, achieving the effect of simultaneously monitoring vibration, temperature, and stress using a single optical fiber. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the structure of the present invention. Figure 1 .

[0032] Figure 2 This is a schematic diagram of the structure of the present invention. Figure 2 .

[0033] The attached diagram is labeled as follows: Signal transmission module 100, signal frequency shifting module 200, signal transmission module 300, BOTDR optical signal processing module 400, DAS optical signal processing module 500, signal processing module 600, fiber under test 700, acousto-optic frequency shifter 210, power amplifier 220, direct digital synthesizer 230, first balanced detector 410, microwave balun 420, microwave low-noise amplifier 430, microwave bandpass filter 440, microwave downconverter circuit 450, intermediate frequency bandpass filter 460. Intermediate frequency amplifier 470, first variable gain amplifier 480, second balanced detector 510, RF balun 520, RF low noise amplifier 530, RF bandpass filter 540, second variable gain amplifier 550, analog-to-digital converter 610, signal processing unit 620, laser emitting unit 110, first coupler 120, circulator 310, first erbium-doped fiber amplifier 321, first optical filter 322, second erbium-doped fiber amplifier 331, second optical filter 332, second coupler 333. Detailed Implementation

[0034] The accompanying drawings are for illustrative purposes only and should not be construed as limiting the scope of this invention. To better illustrate the following embodiments, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0035] Example 1

[0036] Fiber optic sensing technology, as an emerging sensing technology, has been widely applied in recent years with the continuous development of fiber optic technology. Among them, DAS (Distributed Acoustic Sensing) analyzes Rayleigh scattered light returning from optical fibers, supporting vibration and sound measurements, while BOTDR (Brillouin Optical Time Domain Reflectometry) analyzes Brillouin scattered light returning from optical fibers, supporting temperature and stress measurements. To simultaneously monitor vibration, sound, temperature, and stress in optical fibers, current technologies integrate these two techniques into a single device. This involves emitting a laser into the optical fiber, separating the Rayleigh and Brillouin scattered light from the reflected light returning from the fiber, and then using the separated Rayleigh and Brillouin scattered light for vibration, sound, temperature, and stress monitoring.

[0037] However, in existing technologies, photodetectors are usually used to directly separate the two types of scattered light. However, there are certain differences in properties between the two types of scattered light, which makes it impossible to achieve good separation.

[0038] Solutions to the technical problems in the prior art mentioned above, such as Figure 1 As shown, this embodiment provides a signal processing device that integrates DAS and BOTDR. The device may include a signal transmission module 100, a signal frequency shifting module 200, a signal transmission module 300, a BOTDR optical signal processing module 400, a DAS optical signal processing module 500, and a signal processing module 600.

[0039] The first output terminal of the signal transmitting module 100 is connected to the first input terminal of the signal frequency shifting module 200, the second output terminal of the signal transmitting module 100 is connected to the first input terminal of the BOTDR optical signal processing module 400, and the third output terminal of the signal transmitting module 100 is connected to the first input terminal of the DAS optical signal processing module 500; the signal transmitting module 100 transmits continuous optical signals through the first output terminal, the second output terminal, and the third output terminal, respectively.

[0040] The output terminal of the signal frequency shifting module 200 is connected to the input terminal of the signal transmission module 300, and the second input terminal of the signal frequency shifting module 200 is connected to the output terminal of the signal processing module 600. The signal frequency shifting module 200 is used to receive continuous optical signals and convert them into linear sweep pulse light for output.

[0041] The first output terminal of the signal transmission module 300 is used to connect to the optical fiber under test 700, the second output terminal of the signal transmission module 300 is connected to the second input terminal of the BOTDR optical signal processing module 400, and the third output terminal of the signal transmission module 300 is connected to the second input terminal of the DAS optical signal processing module 500; the signal transmission module 300 is used to output linearly swept frequency pulse light to the optical fiber under test 700, and to acquire and output the scattered light returned by the optical fiber under test 700;

[0042] The output terminal of the BOTDR optical signal processing module 400 is connected to the first input terminal of the signal processing module 600, and the output terminal of the DAS optical signal processing module 500 is connected to the second input terminal of the signal processing module 600.

[0043] Understandably, in this embodiment, the signal transmitting module 100 transmits continuous optical signals to the signal frequency shifting module 200, the BOTDR optical signal processing module 400, and the DAS optical signal processing module 500 through its first output terminal, second output terminal, and third output terminal, respectively. After receiving the continuous optical signal, the signal frequency shifting module 200 performs frequency shifting processing on the continuous optical signal and transmits the frequency-shifted continuous optical signal to the signal transmission module 300. The signal transmission module 300 processes the frequency-shifted continuous optical signal and transmits it to the optical fiber under test 700. The optical fiber under test 700 returns various scattered light beams to the signal transmission module 300 for processing. The signal transmission module 300 divides the returned scattered light into two parts, which are respectively input to the BOTDR optical signal processing module 400 and the DAS optical signal processing module 500. In the AS optical signal processing module 500, the BOTDR optical signal processing module 400 and the DAS optical signal processing module 500 respectively use the input continuous optical signal as the local oscillator light, and separate the Brillouin scattered light and Rayleigh scattered light from the scattered light based on the local oscillator light. The Rayleigh scattered light has the same frequency as the continuous optical signal incident on the fiber under test 700, while the Brillouin scattered light has a certain frequency shift difference with the continuous optical signal incident on the fiber under test 700. The continuous optical signal incident on the fiber under test 700 is frequency shifted by the signal frequency shifting module 200, which causes a large frequency shift misalignment between the Brillouin scattered light and the Rayleigh scattered light, thereby enabling better separation of the Brillouin scattered light and Rayleigh scattered light in the BOTDR optical signal processing module 400 and the DAS optical signal processing module 500.

[0044] In one embodiment, the signal frequency shifting module 200 may include an acousto-optic frequency shifter 210, a power amplifier 220, and a direct digital synthesizer 230;

[0045] The first input terminal of the acoustic-optic frequency shifter 210 is connected to the first output terminal of the signal transmitting module 100, and the output terminal of the acoustic-optic frequency shifter 210 is connected to the input terminal of the signal transmission module 300.

[0046] The output terminal of the power amplifier 220 is connected to the second input terminal of the acousto-optic frequency shifter 210, and the input terminal of the power amplifier 220 is connected to the output terminal of the direct digital synthesizer 230; the input terminal of the direct digital synthesizer 230 is connected to the output terminal of the signal processing module 600.

[0047] Understandably, the direct digital synthesizer 230 receives the control signal from the signal processing module 600, causing the direct digital synthesizer to transmit a swept frequency pulse electrical signal to the power amplifier 220. The power amplifier 220 amplifies the swept frequency pulse electrical signal and sends it to the acousto-optic frequency shifter 210, causing the acousto-optic frequency shifter 210 to perform frequency shifting processing on the incident continuous light signal to obtain the linear swept frequency pulse light.

[0048] In one embodiment, the BOTDR optical signal processing module 400 may include a first balanced detector 410, a microwave balun 420, and a microwave amplification component.

[0049] The first input terminal of the first balanced detector 410 is connected to the second output terminal of the signal transmitting module 100, and the second input terminal of the first balanced detector 410 is connected to the second output terminal of the signal transmitting module 300.

[0050] The first input terminal of the microwave balun 420 is connected to the first output terminal of the first balanced detector 410, the second input terminal of the microwave balun 420 is connected to the second output terminal of the first balanced detector 410, and the output terminal of the microwave balun 420 is connected to the input terminal of the microwave amplification component.

[0051] The output terminal of the microwave amplification component is connected to the first input terminal of the signal processing module 600.

[0052] In this embodiment, the first balanced detector 410 is configured with a corresponding bandwidth response, enabling the first balanced detector 410 to separate the Brillouin scattered light of the corresponding frequency from the scattered light based on the continuous light signal, and then input the Brillouin scattered light into the microwave balun 420 for processing, converting the Brillouin scattered light into an unbalanced microwave signal, and then using the microwave amplification component to amplify and filter the microwave signal.

[0053] In one optional embodiment, the microwave amplification assembly may include a microwave low-noise amplifier 430, a microwave bandpass filter 440, a microwave downconversion circuit 450, an intermediate frequency bandpass filter 460, an intermediate frequency amplifier 470, and a first variable gain amplifier 480.

[0054] The microwave low-noise amplifier 430, microwave bandpass filter 440, microwave downconverter circuit 450, intermediate frequency bandpass filter 460, intermediate frequency amplifier 470 and first variable gain amplifier 480 are connected in sequence.

[0055] This can be understood as follows: the input terminal of the microwave low-noise amplifier 430 is connected to the output terminal of the microwave balun 420; the output terminal of the microwave low-noise amplifier 430 is connected to the input terminal of the microwave bandpass filter 440; the output terminal of the microwave bandpass filter 440 is connected to the input terminal of the microwave downconverter circuit 450; the output terminal of the microwave downconverter circuit 450 is connected to the input terminal of the intermediate frequency bandpass filter 460; the output terminal of the intermediate frequency bandpass filter 460 is connected to the input terminal of the intermediate frequency amplifier 470; and the output terminal of the intermediate frequency amplifier 470 is connected to the input terminal of the first variable gain amplifier 480.

[0056] The input terminal of the microwave low-noise amplifier 430 is connected to the output terminal of the microwave balun 420, and the output terminal of the first variable gain amplifier 480 is connected to the first input terminal of the signal processing module 600.

[0057] In one embodiment, the DAS optical signal processing module 500 may include a second balanced detector 510, an RF balun 520, and an RF amplification assembly.

[0058] The first input terminal of the second balance detector 510 is connected to the third output terminal of the signal transmitting module 100, and the second input terminal of the second balance detector 510 is connected to the third output terminal of the signal transmission module 300.

[0059] The first input terminal of the RF balun 520 is connected to the first output terminal of the second balanced detector 510, the second input terminal of the RF balun 520 is connected to the second output terminal of the second balanced detector 510, and the output terminal of the RF balun 520 is connected to the input terminal of the RF amplifier assembly.

[0060] The output terminal of the radio frequency amplification component is connected to the second input terminal of the signal processing module 600.

[0061] In this embodiment, the second balanced detector 510 is configured with a corresponding bandwidth response, enabling the second balanced detector 510 to separate Rayleigh scattered light of the corresponding frequency from the scattered light based on the continuous light signal, and then input the Rayleigh scattered light into the radio frequency balun 520 for processing, converting the Rayleigh scattered light into an unbalanced radio frequency signal, and then using the radio frequency amplification component to amplify and filter the radio frequency signal.

[0062] In one embodiment, the radio frequency amplification assembly may include a radio frequency low noise amplifier 530, a radio frequency bandpass filter 540, and a second variable gain amplifier 550.

[0063] The radio frequency low noise amplifier 530, the radio frequency bandpass filter 540, and the second variable gain amplifier 550 are connected in sequence.

[0064] This can be understood as follows: the output terminal of the RF low-noise amplifier 530 is connected to the input terminal of the RF bandpass filter 540, and the output terminal of the RF bandpass filter 540 is connected to the input terminal of the second variable gain amplifier 550.

[0065] The input terminal of the RF low-noise amplifier 530 is connected to the output terminal of the RF balun 520, and the output terminal of the second variable gain amplifier is connected to the second input terminal of the signal processing module 600.

[0066] In one alternative embodiment, the signal processing module 600 may include an analog-to-digital converter 610 and a signal processing unit 620;

[0067] The first input terminal of the analog-to-digital converter 610 is connected to the output terminal of the BOTDR optical signal processing module 400, the second input terminal of the analog-to-digital converter 610 is connected to the output terminal of the DAS optical signal processing module 500, and the output terminal of the analog-to-digital converter 610 is connected to the input terminal of the signal processing unit 620; the output terminal of the signal processing unit 620 is connected to the second output terminal of the signal frequency shifting module 200. Preferably, the signal processing unit 620 can be configured as an FPGA (Field-Programmable Gate Array).

[0068] In this embodiment, the analog-to-digital converter 610 performs analog-to-digital conversion on the microwave signal and the radio frequency signal processed by the BOTDR optical signal processing module 400 and the DAS optical signal processing module 500, respectively, to obtain digital signals of the corresponding Brillouin scattering light and Rayleigh scattering light. These digital signals are then sent to the signal processing unit 620, simultaneously enabling the monitoring of sound waves, vibrations, temperature, and stress. The signal processing unit 620 can also send control signals to the signal frequency shifting module 200.

[0069] In one optional implementation, the signal transmitting module 100 may include a laser transmitting unit 110 and a first coupler 120;

[0070] The laser emitting unit 110 is used to emit continuous optical signals. Preferably, the laser emitting unit 110 can be configured as a narrow linewidth laser. The output terminal of the laser emitting unit 110 is connected to the input terminal of the first coupler 120. The first output terminal of the first coupler 120 is connected to the first input terminal of the signal frequency shifting module 200. The second output terminal of the first coupler 120 is connected to the first input terminal of the BOTDR optical signal processing module 400. The third output terminal of the first coupler 120 is connected to the first input terminal of the DAS optical signal processing module 500.

[0071] Understandably, the laser emitting unit 110 is used to emit continuous optical signals. After the continuous optical signals enter the first coupler 120, three identical continuous optical signals are obtained through the first coupler 120, and then emitted to the signal frequency shifting module 200, the BOTDR optical signal processing module 400 and the DAS optical signal processing module 500 respectively through the first output port, the second output port and the third output port of the first coupler 120.

[0072] In one optional implementation, the signal transmission module 300 may include a circulator 310, a first optical amplification component, and a second optical amplification component;

[0073] The input terminal of the first optical amplification component is connected to the output terminal of the signal frequency shifting module, the output terminal of the first optical amplification component is connected to the first transmission terminal of the circulator 310, the second transmission terminal of the circulator 310 is used to connect to the optical fiber under test 700, the third transmission terminal of the circulator 310 is connected to the input terminal of the second optical amplification component, the first output terminal of the second optical amplification component is connected to the second input terminal of the BOTDR optical signal processing module 400, and the second output terminal of the second optical amplification component is connected to the second input terminal of the DAS optical signal processing module 500.

[0074] The first optical amplification component may include a first erbium-doped fiber amplifier 321 and a first optical filter 322 connected in sequence. The input end of the first erbium-doped fiber amplifier 321 is connected to the output end of the signal frequency shift module 200, and the output end of the first optical filter 322 is connected to the first transmission end of the circulator 310.

[0075] The second optical amplification component may include a second erbium-doped fiber amplifier 331, a second optical filter 332, and a second coupler 333 connected in sequence; the input end of the second erbium-doped fiber amplifier 331 is connected to the third transmission end of the circulator 310, the first output end of the second coupler 333 is connected to the second input end of the BOTDR optical signal processing module 400, and the second output end of the second coupler 333 is connected to the second input end of the DAS optical signal processing module 500.

[0076] In one alternative implementation, such as Figure 2 As shown, the device includes a signal transmitting module 100, a signal frequency shifting module 200, a signal transmission module 300, a BOTDR optical signal processing module 400, a DAS optical signal processing module 500, and a signal processing module 600.

[0077] The signal frequency shifting module 200 includes an acousto-optic frequency shifter 210, a power amplifier 220, and a direct digital synthesizer 230.

[0078] The BOTDR optical signal processing module 400 includes a first balanced detector 410, a microwave balun 420, and a microwave amplification component; the microwave amplification component includes a microwave low-noise amplifier 430, a microwave bandpass filter 440, a microwave downconversion circuit 450, an intermediate frequency bandpass filter 460, an intermediate frequency amplifier 470, and a first variable gain amplifier 480 connected in sequence.

[0079] The DAS optical signal processing module 500 includes a second balanced detector 510, an RF balun 520, and an RF amplification component; the RF amplification component includes an RF low-noise amplifier 530, an RF bandpass filter 540, and a second variable gain amplifier 550 connected in sequence.

[0080] The signal processing module 600 includes an analog-to-digital converter 610 and a signal processing unit 620; the signal transmitting module 100 includes a laser transmitting unit 110 and a first coupler 120.

[0081] The signal transmission module 300 includes a circulator 310, a first optical amplification component, and a second optical amplification component. The first optical amplification component includes a first erbium-doped fiber amplifier 321 and a first optical filter 322 connected in sequence. The second optical amplification component includes a second erbium-doped fiber amplifier 331, a second optical filter 332, and a second coupler 333 connected in sequence. The first transmission end of the circulator 310 is connected to the output end of the first optical filter 322, the second transmission end of the circulator 310 is used to connect to the fiber under test 700, and the third transmission end of the circulator 310 is connected to the input end of the second erbium-doped fiber amplifier 331.

[0082] In this embodiment, the output terminal of the laser emitting unit 110 is connected to the input terminal of the first coupler 120, the first output terminal of the first coupler 120 is connected to the first input terminal of the acousto-optic frequency shifter 210, the second output terminal of the first coupler 120 is connected to the first input terminal of the first balanced detector 410, and the third output terminal of the first coupler 120 is connected to the first input terminal of the second balanced detector 510.

[0083] The first input unit of the acousto-optic frequency shifter 210 is connected to the first output terminal of the first coupler 120, the output terminal of the acousto-optic frequency shifter 210 is connected to the first erbium-doped fiber amplifier 321, the input terminal of the direct digital synthesizer 230 is connected to the output terminal of the signal processing unit 620, the first output terminal of the second coupler 333 is connected to the second input terminal of the first balanced detector 410, and the second output terminal of the second coupler 333 is connected to the second input terminal of the first balanced detector 410.

[0084] The output of the microwave balun 420 is connected to the input of the microwave low-noise amplifier 430, the output of the radio frequency balun 520 is connected to the input of the radio frequency low-noise amplifier 530, the output of the first variable gain amplifier 480 is connected to the first input of the analog-to-digital converter 610, and the output of the second variable gain amplifier 550 is connected to the second input of the analog-to-digital converter 610.

[0085] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the technical solution of this utility model, and are not intended to limit the specific implementation of this utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the claims of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A signal processing device integrating DAS and BOTDR, characterized in that, The device includes a signal transmitting module, a signal frequency shifting module, a signal transmission module, a BOTDR optical signal processing module, a DAS optical signal processing module, and a signal processing module. The first output terminal of the signal transmitting module is connected to the first input terminal of the signal frequency shifting module, the second output terminal of the signal transmitting module is connected to the first input terminal of the BOTDR optical signal processing module, and the third output terminal of the signal transmitting module is connected to the first input terminal of the DAS optical signal processing module. The signal transmitting module transmits continuous optical signals through the first output terminal, the second output terminal, and the third output terminal, respectively. The output terminal of the signal frequency shifting module is connected to the input terminal of the signal transmission module, and the second input terminal of the signal frequency shifting module is connected to the output terminal of the signal processing module. The signal frequency shifting module is used to receive continuous optical signals and convert them into linear sweeping pulse light for output. The first output terminal of the signal transmission module is used to connect to the optical fiber under test, the second output terminal of the signal transmission module is connected to the second input terminal of the BOTDR optical signal processing module, and the third output terminal of the signal transmission module is connected to the second input terminal of the DAS optical signal processing module; the signal transmission module is used to output linearly swept frequency pulse light to the optical fiber under test, and to acquire and output the scattered light returned by the optical fiber under test. The output terminal of the BOTDR optical signal processing module is connected to the first input terminal of the signal processing module, and the output terminal of the DAS optical signal processing module is connected to the second input terminal of the signal processing module.

2. The signal processing apparatus integrating DAS and BOTDR according to claim 1, characterized in that, The signal frequency shifting module includes an acousto-optic frequency shifter, a power amplifier, and a direct digital synthesizer; The first input terminal of the acousto-optic frequency shifter is connected to the first output terminal of the signal transmitting module, and the output terminal of the acousto-optic frequency shifter is connected to the input terminal of the signal transmitting module. The output terminal of the power amplifier is connected to the second input terminal of the acousto-optic frequency shifter, and the input terminal of the power amplifier is connected to the output terminal of the direct digital synthesizer; the input terminal of the direct digital synthesizer is connected to the output terminal of the signal processing module.

3. The signal processing apparatus integrating DAS and BOTDR according to claim 1, characterized in that, The BOTDR optical signal processing module includes a first balanced detector, a microwave balun, and a microwave amplification assembly. The first input terminal of the first balanced detector is connected to the second output terminal of the signal transmitting module, and the second input terminal of the first balanced detector is connected to the second output terminal of the signal transmitting module. The first input terminal of the microwave balun is connected to the first output terminal of the first balanced detector, the second input terminal of the microwave balun is connected to the second output terminal of the first balanced detector, and the output terminal of the microwave balun is connected to the input terminal of the microwave amplification component. The output terminal of the microwave amplification component is connected to the first input terminal of the signal processing module.

4. The signal processing apparatus integrating DAS and BOTDR according to claim 3, characterized in that, The microwave amplification assembly includes a microwave low-noise amplifier, a microwave bandpass filter, a microwave downconversion circuit, an intermediate frequency bandpass filter, an intermediate frequency amplifier, and a first variable gain amplifier connected in sequence. The input terminal of the microwave low-noise amplifier is connected to the output terminal of the microwave balun, and the output terminal of the first variable gain amplifier is connected to the first input terminal of the signal processing module.

5. The signal processing apparatus integrating DAS and BOTDR according to claim 1, characterized in that, The DAS optical signal processing module includes a second balanced detector, an RF balun, and an RF amplification component. The first input terminal of the second balanced detector is connected to the third output terminal of the signal transmitting module, and the second input terminal of the second balanced detector is connected to the third output terminal of the signal transmitting module; The first input terminal of the radio frequency balun is connected to the first output terminal of the second balanced detector, the second input terminal of the radio frequency balun is connected to the second output terminal of the second balanced detector, and the output terminal of the radio frequency balun is connected to the input terminal of the radio frequency amplification component. The output terminal of the radio frequency amplification component is connected to the second input terminal of the signal processing module.

6. The signal processing apparatus integrating DAS and BOTDR according to claim 5, characterized in that, The radio frequency amplification assembly includes a radio frequency low noise amplifier, a radio frequency bandpass filter, and a second variable gain amplifier connected in sequence. The input terminal of the RF low-noise amplifier is connected to the output terminal of the RF balun, and the output terminal of the second variable gain amplifier is connected to the second input terminal of the signal processing module.

7. The signal processing apparatus for integrating DAS and BOTDR according to any one of claims 1-6, characterized in that, The signal processing module includes an analog-to-digital converter and a signal processing unit; The first input terminal of the analog-to-digital converter is connected to the output terminal of the BOTDR optical signal processing module, the second input terminal of the analog-to-digital converter is connected to the output terminal of the DAS optical signal processing module, the output terminal of the analog-to-digital converter is connected to the input terminal of the signal processing unit, and the output terminal of the signal processing unit is connected to the second input terminal of the signal frequency shifting module.

8. The signal processing apparatus for integrating DAS and BOTDR according to any one of claims 1-6, characterized in that, The signal transmitting module includes a laser transmitting unit and a first coupler; The laser emitting unit is used to emit continuous optical signals. The output end of the laser emitting unit is connected to the input end of the first coupler. The first output end of the first coupler is connected to the first input end of the signal frequency shifting module. The second output end of the first coupler is connected to the first input end of the BOTDR optical signal processing module. The third output end of the first coupler is connected to the first input end of the DAS optical signal processing module.

9. The signal processing apparatus for integrating DAS and BOTDR according to any one of claims 1-6, characterized in that, The signal transmission module includes a circulator, a first optical amplification component, and a second optical amplification component; The input terminal of the first optical amplification component is connected to the output terminal of the signal frequency shifting module, the output terminal of the first optical amplification component is connected to the first transmission terminal of the circulator, the second transmission terminal of the circulator is used to connect to the optical fiber under test, the third transmission terminal of the circulator is connected to the input terminal of the second optical amplification component, the first output terminal of the second optical amplification component is connected to the second input terminal of the BOTDR optical signal processing module, and the second output terminal of the second optical amplification component is connected to the second input terminal of the DAS optical signal processing module.

10. The signal processing apparatus integrating DAS and BOTDR according to claim 9, characterized in that, The first optical amplification component includes a first erbium-doped fiber amplifier and a first optical filter connected in sequence. The input end of the first erbium-doped fiber amplifier is connected to the output end of the signal frequency shift module, and the output end of the first optical filter is connected to the first transmission end of the circulator. The second optical amplification component includes a second erbium-doped fiber amplifier, a second optical filter, and a second coupler connected in sequence; the input end of the second erbium-doped fiber amplifier is connected to the third transmission end of the circulator, the first output end of the second coupler is connected to the second input end of the BOTDR optical signal processing module, and the second output end of the second coupler is connected to the second input end of the DAS optical signal processing module.

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