BOTDR equipment
By introducing light source, light separation, light transmission, light signal processing, and power adjustment modules into the BOTDR device, the optical signal power can be monitored and adjusted in real time, solving the problem of unstable optical signal power affecting measurement results and improving measurement accuracy.
Patent Information
- Application Number
- CN202422996649.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-04
- Publication Date
- 2025-10-21
- Estimated Expiration
- 2034-12-04
AI Technical Summary
Existing BOTDR equipment cannot achieve stable control of the output power of optical signals, which affects subsequent measurement results.
By introducing a light source module, an optical separation module, an optical transmission module, an optical signal processing module, and a power adjustment module into the BOTDR device, the optical signal power output by the light source module is monitored in real time, and the output of the light source module is adjusted through feedback by the power adjustment module to ensure the stability of the optical signal power.
This achieves stable output of optical signal power, improves the accuracy of subsequent measurements, and reduces the impact of optical signal power variations on measurement results.
Smart Images
Figure CN223461046U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the field of optical sensing devices, and in particular to a BOTDR device. BACKGROUND
[0002] With the development of optical sensing technology, it has gradually been popularized in various dangerous operation scenes, and in particular, optical sensing devices such as BOTDR (Brillouin Optical Time Domain Reflectometry) devices are used to detect parameters such as temperature and stress at various positions in the scene.
[0003] The current BOTDR device mainly includes a light source, an optical fiber transmission line, a photoelectric detector, and a signal processing unit and other modules. However, in order to improve the transmission efficiency of the optical signal and the stability of the system, it is often necessary to introduce additional functional modules in the system, such as merging and separating of optical signals, amplification of optical signals, etc. Although the addition of functional modules can meet the needs to some extent, when the power of the optical signal changes, it will still affect the detection results. CONTENT OF THE UTILITY MODEL
[0004] In view of this, the present application proposes a BOTDR device to solve the problem that the existing BOTDR device cannot realize stable control of the output power of the optical signal, thereby affecting the subsequent measurement results.
[0005] The first aspect of the present application provides a BOTDR device, comprising: a light source module, an optical separation module, an optical transmission module, an optical signal processing module, and a power adjustment module;
[0006] The output end of the light source module is connected with the input end of the optical separation module, and the input end of the light source module is connected with the first output end of the power adjustment module;
[0007] The first output end of the optical separation module is connected with the first input end of the optical transmission module, the second output end of the optical separation module is connected with the first input end of the optical signal processing module, and the third output end of the optical separation module is connected with the first input end of the power adjustment module;
[0008] The first transmission end of the optical transmission module is used to be connected with a to-be-measured optical fiber, the second transmission end of the optical transmission module is connected with the third input end of the optical signal processing module, and the second input end of the optical transmission module is connected with the second output end of the optical signal processing module;
[0009] The second output end of the power adjustment module is connected with the second input end of the optical signal processing module, and the second input end of the power adjustment module is connected with the output end of the optical signal processing module.
[0010] In an implementation, the light separation module comprises a first coupler and a second coupler;
[0011] The input end of the first coupler is connected with the output end of the light source module, for separating the light signal of preset power and narrow line width output by the light source module into a first light signal and a second light signal according to a first proportion, wherein the first light signal is output to the second coupler, and the second light signal is output to the power adjustment module.
[0012] The input end of the second coupler is connected with the first coupler, for separating the first light signal into a sensing light signal and a local oscillator light signal according to a second proportion, wherein the sensing light signal is output to the light transmission module, and the local oscillator light signal is output to the light signal processing module.
[0013] In an implementation, the power adjustment module comprises a power collection unit and a laser current control circuit.
[0014] The input end of the power collection unit is connected with the first coupler, and the output end of the power collection unit is connected with the light signal processing module, for collecting the power of the second light signal and outputting to the light signal processing module.
[0015] The input end of the laser current control circuit is connected with the first output end of the light signal processing module, and the output end of the laser current control circuit is connected with the input end of the light source module, for receiving the current output by the light signal processing module to adjust the power of the light signal provided by the light source module.
[0016] In an implementation, the power collection unit comprises a photodiode and a first collection circuit connected in series.
[0017] The input end of the photodiode is connected with the first coupler, for converting the second light signal into an analog electric signal and outputting to the first collection circuit.
[0018] The input end of the first collection circuit is connected with the output end of the photodiode, and the output end of the first collection circuit is connected with the second input end of the light signal processing module, for receiving the analog electric signal and converting it into a digital signal and outputting to the light signal processing module.
[0019] In an implementation, the first collection circuit comprises an analog-to-digital converter and a signal processing chip.
[0020] After the analog-to-digital converter and the signal processing chip are connected in series, the input end of the analog-to-digital converter is connected with the output end of the photodiode, and the output end of the signal processing chip is connected with the second input end of the light signal processing module.
[0021] In a feasible embodiment, the optical transmission module includes: an optical signal amplifying circuit and a circulator;
[0022] The first input end of the optical signal amplifying circuit is connected to the first output end of the optical separation module, the second input end of the optical signal amplifying circuit is connected to the second output end of the optical signal processing module, and the output end of the optical signal amplifying circuit is connected to the input end of the circulator, so as to amplify the sensing light signal separated from the first light signal and output it to the optical fiber to be tested through the circulator.
[0023] In a feasible implementation manner, the optical signal amplification circuit includes a first erbium-doped fiber amplifier and a semiconductor optical amplifier;
[0024] The input end of the first erbium-doped fiber amplifier is connected to the output end of the semiconductor optical amplifier, the input end of the semiconductor optical amplifier is connected to the first output end of the optical separation module, the output end of the first erbium-doped fiber amplifier is connected to the input end of the circulator, and the semiconductor optical amplifier is connected to the optical separation module.
[0025] In a feasible implementation manner, the optical signal processing module includes a third coupler, an optical signal receiving circuit and a signal processing circuit;
[0026] The input end of the optical signal receiving circuit is connected to the output end of the circulator, and is used to receive the optical signal returned by the circulator, and output it to the third coupler after amplification;
[0027] The third coupler is connected to the optical signal receiving circuit, the signal processing circuit and the optical separation module respectively, and is used to combine the local oscillator optical signal separated from the first optical signal and the optical signal returned by the circulator into a coupled optical signal, and output the combined signal to the signal processing circuit;
[0028] The signal processing circuit is connected to the optical transmission module, the third coupler and the power adjustment module respectively, and is used to output a current signal to the power adjustment module.
[0029] In a feasible implementation manner, the signal processing circuit includes an analog-to-digital conversion processing circuit and a microcontroller;
[0030] The input end of the analog-to-digital conversion processing circuit is connected to the second output end of the power adjustment module, the output end of the analog-to-digital conversion processing circuit is connected to the microcontroller, and the controller is respectively connected to the third coupler, the second input end of the optical transmission module and the second input end of the power adjustment module.
[0031] In an embodiment, the optical signal receiving circuit comprises an optical filter and a second erbium-doped fiber amplifier.
[0032] The input end of the optical filter is connected with the output end of the second erbium-doped fiber amplifier, the output end of the optical filter is connected with the third coupler, and the input end of the second erbium-doped fiber amplifier is connected with the first output end of the circulator.
[0033] In the technical scheme provided in the application, the BOTDR device comprises an optical source module, an optical separation module, an optical transmission module, an optical signal processing module and a power adjustment module; the output end of the optical source module is connected with the input end of the optical separation module, the input end of the optical source module is connected with the first output end of the power adjustment module; the first output end of the optical separation module is connected with the first input end of the optical transmission module, the second output end of the optical separation module is connected with the first input end of the optical signal processing module, and the third output end of the optical separation module is connected with the first input end of the power adjustment module; the first transmission end of the optical transmission module is connected with a fiber to be measured, and the second transmission end of the optical transmission module is connected with the third input end of the optical signal processing module; the second output end of the power adjustment module is connected with the second input end of the optical signal processing module, and the second input end of the power adjustment module is connected with the first output end of the optical signal processing module. The power of the optical signal output by the optical source module is monitored in real time by the optical signal processing module, and the power monitored by the power adjustment module is returned to adjust the power of the optical signal output by the optical source module, so as to ensure the stability of the power of the output optical signal and improve the accuracy of subsequent measurement. BRIEF DESCRIPTION OF DRAWINGS
[0034] Figure 1 The first schematic diagram of the BOTDR device provided in the embodiment of the application;
[0035] Figure 2 The second schematic diagram of the BOTDR device provided in the embodiment of the application;
[0036] Figure 3 The third schematic diagram of the BOTDR device provided in the embodiment of the application. DETAILED DESCRIPTION
[0037] The terms "first", "second", "third", "fourth" and the like in the description and in the claims of the present application, if any, are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the use of these terms herein is to be construed as interchangeable in order to comfort with the context of the description and the claims. Furthermore, the terms "comprise", "comprising", "include", "including", and the like, if any, are used synonymously to comprise and / or having. It is to be understood that, where the description, the claims, or the figures disclose or suggest that something can be comprised, included, combined, joined, attached or the like of something else, it can also be possible for the described or suggested thing to be stand-alone, without the other thing being present.
[0038] As Figure 1 shown, the BOTDR device provided by the embodiments of the present application comprises:
[0039] an optical source module 110, an optical splitting module 120, an optical transmission module 130, an optical signal processing module 140 and a power adjustment module 150;
[0040] The output end of the optical source module 110 is connected with the input end of the optical splitting module 120, and the input end of the optical source module 110 is connected with the first output end of the power adjustment module 150;
[0041] The first output end of the optical splitting module 120 is connected with the first input end of the optical transmission module 130, the second output end of the optical splitting module 120 is connected with the first input end of the optical signal processing module 140, and the third output end of the optical splitting module 120 is connected with the first input end of the power adjustment module 150;
[0042] The first transmission end of the optical transmission module 130 is connected with the optical fiber to be measured, the second transmission end of the optical transmission module 130 is connected with the third input end of the optical signal processing module 140, and the second input end of the optical transmission module 130 is connected with the second output end of the optical signal processing module 140;
[0043] The second output end of the power adjustment module 150 is connected with the second input end of the optical signal processing module 140, and the second input end of the power adjustment module 150 is connected with the first output end of the optical signal processing module 140.
[0044] In the embodiment, the light source module 110 is a narrow line width laser, which is used to generate a preset power, narrow line width optical signal and output to the light separation module 120. The light separation module 120 separates the optical signal output by the light source module 110 into at least two beams of light and outputs to the optical transmission module 130, the optical signal processing module 140 and the power adjustment module 150 respectively.
[0045] The optical transmission module 130 is used to amplify and process the optical signal separated by the light separation module 120 and output to the optical fiber to be tested for subsequent monitoring. The optical transmission module 130 is also used to receive the returned optical signal in the optical fiber to be tested and output to the optical signal processing module 140 for analysis.
[0046] The power adjustment module 150 is used to convert the optical signal separated by the light separation module 120 and output to the optical signal processing module 140, and receive the current adjustment optical signal output by the light source module 110.
[0047] The circuit structure realizes real-time monitoring of the optical signal power, and feeds back the power adjustment module based on the monitoring result to adjust the power of the optical signal output by the light source module, so as to ensure the stable output of the optical signal power and avoid affecting the monitoring and measurement results when the optical signal is used for monitoring and measurement.
[0048] In a feasible implementation manner, as shown in Figure 2 The light separation module 120 includes a first coupler 121 and a second coupler 122.
[0049] The input end of the first coupler 121 is connected with the light source module 110, which is used to divide the preset power, narrow line width optical signal output by the light source module 110 into a first optical signal and a second optical signal according to a first proportion. The first optical signal is output to the second coupler 122, and the second optical signal is output to the power adjustment module 150.
[0050] The input end of the second coupler 122 is connected with the first coupler 121, which is used to divide the first optical signal into a sensing optical signal and a local oscillator optical signal according to a second proportion. The sensing optical signal is output to the optical transmission module 130, and the local oscillator optical signal is output to the optical signal processing module 140.
[0051] It should be noted that the first optical signal and the second optical signal divided by the first coupler 121 according to the first proportion have a proportion of the first optical signal greater than that of the second optical signal, but the parameters of the two optical signals are completely same. Similarly, the proportion of the sensing optical signal separated by the second coupler 122 is greater than that of the local oscillator optical signal, and the two are also same signals.
[0052] The first coupler 121 and the second coupler 122 are composed of a plurality of optical elements (such as beam splitters, mirrors, etc.) and circuits (such as control circuits, driving circuits, etc.) to realize the separation of optical signals.
[0053] In the embodiment, the power adjustment module 150 comprises a power collection unit 151 and a laser current control circuit 152.
[0054] The input end of the power collection unit 151 is connected with the first coupler 121, and the output end of the power collection unit 151 is connected with the optical signal processing module 140, for collecting the power of the second optical signal and outputting to the optical signal processing module 140.
[0055] The input end of the laser current control circuit 152 is connected with the first output end of the optical signal processing module 140, and the output end of the laser current control circuit 152 is connected with the input end of the light source module 110, for receiving the current output by the optical signal processing module 140 to adjust the power of the optical signal provided by the light source module 110. That is, the laser current control circuit 152 adjusts the current of the light source module 110 to ensure the stable operation of the light source module 110 and generate the required output power.
[0056] It should be noted that the power collection unit 151 converts the second optical signal output by the first coupler 121 into a digital signal after analog-to-digital conversion, and outputs the digital signal to the optical signal processing module 140 for power analysis and to obtain the result of the adjustment current.
[0057] Specifically, the power collection unit 151 comprises a photodiode 1511 and a first collection circuit 1512 connected in series; wherein the photodiode 1511 is a small-bandwidth photodiode, and in addition, a preamplifier, a filter, or other circuit elements can be used instead, for converting the second optical signal into an electrical signal and performing preliminary processing.
[0058] The input end of the photodiode 1511 is connected with the first coupler 121, for converting the second optical signal into an analog electrical signal and outputting to the first collection circuit 1512.
[0059] The input end of the first collection circuit 1512 is connected with the output end of the photodiode 1511, and the output end of the first collection circuit 1512 is connected with the second input end of the optical signal processing module 140, for receiving the analog electrical signal and converting it into a digital signal and outputting to the optical signal processing module 140.
[0060] In practical application, the first acquisition circuit 1512 includes an analog-to-digital converter and a signal processing chip; the input end of the analog-to-digital converter is connected with the output end of the photodiode 1511 in series after the analog-to-digital converter and the signal processing chip are connected in series, and the output end of the signal processing chip is connected with the second input end of the optical signal processing module 140.
[0061] In a feasible embodiment, the optical transmission module 130 includes an optical signal amplification circuit 131 and a circulator 132.
[0062] The first input end of the optical signal amplification circuit 131 is connected with the first output end of the optical separation module 120, the second input end of the optical signal amplification circuit 131 is connected with the second output end of the optical signal processing module 140, and the output end of the optical signal amplification circuit 131 is connected with the input end of the circulator 132, so as to amplify the sensing optical signal separated from the first optical signal and output to the optical fiber to be measured through the circulator 132. The circulator 132 can internally include optical elements and circuits to realize reflection and transmission of light.
[0063] It should be noted that the optical signal amplification circuit 131 is composed of a SOA (Semi-conductor Optical Amplifier) and a first EDFA (Erbium Doped Fiber Amplifier), the input end of the first EDFA is connected with the output end of the SOA, the input end of the SOA is connected with the first output end of the optical separation module 120, the output end of the first EDFA is connected with the input end of the circulator 132, and the SOA is connected with the optical separation module 120. After the first EDFA and the SOA, the first EDFA is connected with the circulator 132, and the SOA is connected with the optical separation module 120 (i.e. connected with the second coupler 122 in the optical separation module 120), as shown in Figure 3 .
[0064] In another embodiment, the optical signal processing module 140 includes a third coupler 141, an optical signal receiving circuit 142 and a signal processing circuit 143.
[0065] The input end of the optical signal receiving circuit 142 is connected with the circulator 152, so as to receive the optical signal returned by the circulator 152, amplify and output to the third coupler 141.
[0066] The third coupler 141 is connected with the optical signal receiving circuit 142, the signal processing circuit 143 and the optical separation module 120 respectively, for synthesizing the local oscillator optical signal separated from the first optical signal and the optical signal returned by the circulator 152 into a coupled optical signal, and outputting to the signal processing circuit 143;
[0067] The signal processing circuit 143 is connected with the optical transmission module 130, the third coupler 141 and the power adjustment module 150 respectively, for outputting the current signal to the power adjustment module 150.
[0068] It should be noted that the third coupler 141 is a synthesizer, for coupling the returned optical signal received by the circulator 152 and the optical signal separated by the second coupler 122, completing the local oscillator control, and outputting to the signal processing circuit 143.
[0069] It can be understood that the signal processing circuit 143 includes an analog-to-digital conversion processing circuit and a microcontroller;
[0070] The input end of the analog-to-digital conversion processing circuit is connected with the second output end of the power adjustment module 150, the output end of the analog-to-digital conversion processing circuit is connected with the microcontroller, and the microcontroller is connected with the third coupler 141, the second input end of the optical transmission module 130 and the second input end of the power adjustment module 150 respectively.
[0071] In the embodiment, the optical signal receiving circuit 142 includes an optical filter and a second erbium-doped fiber amplifier, the input end of the optical filter is connected with the output end of the second erbium-doped fiber amplifier, the output end of the optical filter is connected with the third coupler 141, and the input end of the second erbium-doped fiber amplifier is connected with the first output end of the circulator 132. The optical filter is composed of interference filter, grating and other optical elements, without additional circuit structure.
[0072] In actual application, the optical signal processing circuit 143 further includes an optical diode PD and a collection unit, wherein the optical diode PD is a large broadband optical diode, and the collection unit is composed of an ADC digital-to-analog converter and an FPGA, as shown in Figure 3
[0073] In summary, the BOTDR device provided by the embodiment adds a first coupler, a photodiode, a first acquisition circuit and a laser current control circuit in the circuit structure. The first coupler, the photodiode and the first acquisition circuit acquire the power of the optical signal output by the light source module in real time and provide the optical signal processing module, so as to realize real-time monitoring of the power of the optical signal output by the light source module. When the power changes, the laser current control circuit is adjusted to keep the power of the optical signal output by the light source module stable, so that the BOTDR measurement result is not affected by the power change of the optical signal, and the BOTDR result is more accurate.
[0074] Finally, it should be noted that the above embodiments are only specific implementations of the present application, which are used to illustrate the technical solutions of the present application, but not to limit them. The protection scope of the present application is not limited to this. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can modify or easily think of changes to the technical solutions recorded in the foregoing embodiments, or make equivalent replacements to some technical features, within the technical scope disclosed by the present application. These modifications, changes or replacements do not make the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.
Claims
1. A BOTDR device, characterized in that: The application relates to an optical fiber sensing system. The optical fiber sensing system comprises a light source module, a light separation module, a light transmission module, a light signal processing module and a power adjustment module. The output end of the light source module is connected with the input end of the light separation module, and the input end of the light source module is connected with the first output end of the power adjustment module. The first output end of the light separation module is connected with the first input end of the light transmission module, the second output end of the light separation module is connected with the first input end of the light signal processing module, and the third output end of the light separation module is connected with the first input end of the power adjustment module. The first transmission end of the light transmission module is used for being connected with a to-be-detected optical fiber, the second transmission end of the light transmission module is connected with the third input end of the light signal processing module, the second input end of the light transmission module is connected with the second output end of the light signal processing module, the second output end of the power adjustment module is connected with the second input end of the light signal processing module, and the second input end of the power adjustment module is connected with the first output end of the light signal processing module. The light separation module comprises a first coupler and a second coupler.
2. The BOTDR apparatus according to claim 1, characterized by The input end of the first coupler is connected with the output end of the light source module, and the first coupler is used for dividing the light signal of a preset power and a narrow line width output by the light source module into a first light signal and a second light signal according to a first proportion, wherein the first light signal is output to the second coupler, and the second light signal is output to the power adjustment module. The input end of the second coupler is connected with the first coupler, and the second coupler is used for dividing the first light signal into a sensing light signal and a local oscillation light signal according to a second proportion, wherein the sensing light signal is output to the light transmission module, and the local oscillation light signal is output to the light signal processing module. The power adjustment module comprises a power collection unit and a laser current control circuit.
3. The BOTDR apparatus according to claim 2, characterized by The input end of the power collection unit is connected with the first coupler, and the output end of the power collection unit is connected with the light signal processing module, and the power collection unit is used for collecting the power of the second light signal and outputting the power to the light signal processing module. The input end of the laser current control circuit is connected with the first output end of the light signal processing module, and the output end of the laser current control circuit is connected with the input end of the light source module, and the laser current control circuit is used for receiving the current output by the light signal processing module to adjust the power of the light signal provided by the light source module. The power collection unit comprises a photodiode and a first collection circuit in series.
4. The BOTDR apparatus according to claim 3, characterized by The input end of the photodiode is connected with the first coupler, and the photodiode is used for converting the second light signal into an analog electric signal and outputting the analog electric signal to the first collection circuit. The input end of the first collection circuit is connected with the output end of the photodiode, the output end of the first collection circuit is connected with the second input end of the light signal processing module, and the first collection circuit is used for receiving the analog electric signal and converting the analog electric signal into a digital signal and outputting the digital signal to the light signal processing module. The first collection circuit comprises an analog-to-digital converter and a signal processing chip.
5. The BOTDR apparatus according to claim 4, wherein The input end of the analog-digital converter is connected with the output end of the photoelectric diode after the analog-digital converter is connected in series with the signal processing chip, and the output end of the signal processing chip is connected with the second input end of the optical signal processing module.
6. The BOTDR apparatus according to any one of claims 1 to 5, characterized by The optical transmission module comprises an optical signal amplification circuit and a circulator. The first input end of the optical signal amplification circuit is connected with the first output end of the optical separation module, the second input end of the optical signal amplification circuit is connected with the second output end of the optical signal processing module, and the output end of the optical signal amplification circuit is connected with the input end of the circulator, so as to amplify the sensing optical signal separated from the first optical signal and output the amplified sensing optical signal to the optical fiber to be measured through the circulator.
7. The BOTDR apparatus according to claim 6, wherein The optical signal amplification circuit comprises a first erbium-doped fiber amplifier and a semiconductor optical amplifier. The input end of the first erbium-doped fiber amplifier is connected with the output end of the semiconductor optical amplifier, the input end of the semiconductor optical amplifier is connected with the first output end of the optical separation module, the output end of the first erbium-doped fiber amplifier is connected with the input end of the circulator, and the semiconductor optical amplifier is connected with the optical separation module.
8. The BOTDR apparatus according to claim 6, wherein The optical signal processing module comprises a third coupler, an optical signal receiving circuit and a signal processing circuit. The input end of the optical signal receiving circuit is connected with the circulator, so as to receive the optical signal returned by the circulator, amplify the received optical signal and output the amplified optical signal to the third coupler. The third coupler is connected with the optical signal receiving circuit, the signal processing circuit and the optical separation module respectively, so as to synthesize the local oscillator optical signal separated from the first optical signal and the optical signal returned by the circulator into a coupled optical signal and output the coupled optical signal to the signal processing circuit. The signal processing circuit is connected with the optical transmission module, the third coupler and the power adjustment module respectively, so as to output a current signal to the power adjustment module.
9. The BOTDR apparatus according to claim 8, characterized by The signal processing circuit comprises an analog-digital conversion processing circuit and a microcontroller. The input end of the analog-digital conversion processing circuit is connected with the second output end of the power adjustment module, the output end of the analog-digital conversion processing circuit is connected with the microcontroller, and the microcontroller is connected with the third coupler, the second input end of the optical transmission module and the second input end of the power adjustment module respectively.
10. The BOTDR apparatus according to claim 9, wherein The optical signal receiving circuit comprises an optical filter and a second erbium-doped fiber amplifier. The input end of the optical filter is connected with the output end of the second erbium-doped fiber amplifier, the output end of the optical filter is connected with the third coupler, and the input end of the second erbium-doped fiber amplifier is connected with the first output end of the circulator.