Method, device and storage medium for measuring optical fiber temperature and / or strain

Abstract

The embodiments of the present application provide a method, device, and storage medium for measuring optical fiber temperature and / or strain, relating to the field of distributed optical fiber technology. The method comprises: obtaining a first high-frequency optical signal and a second low-frequency optical signal at any linear modulation frequency, and converting them into a first electrical signal and a second electrical signal; determining the average of the Brillouin attenuation and gain values ​​corresponding to the first electrical signal and the second electrical signal based on the central symmetry of BGS and BLS, and determining the measurement result of the temperature and / or strain of the optical fiber to be measured based on the Brillouin frequency shift determined from all the first average values. The present application utilizes the central symmetry of BGS and BLS to convert the high-frequency optical signal and the low-frequency optical signal obtained by the original SA-BOTDA into electrical signals and then average them, thereby suppressing the phase-to-intensity noise caused by the frequency shift of the high-frequency and low-frequency optical signals affected by the laser phase noise, and reconstructing the Brillouin gain spectrum, thereby reducing the impact of the laser linewidth on the signal-to-noise ratio.

Description

Technical Field

[0001] The present application relates to the field of distributed optical fiber technology, and in particular to a method, device, and storage medium for measuring optical fiber temperature and / or strain. Background Art

[0002] Brillouin Optical Time Domain Analysis (BOTDA), a new distributed sensing technology, has become a research hotspot in the field of fiber optic sensing applications, both domestically and internationally, due to its advantages such as high detection signal strength, high measurement accuracy, wide dynamic range, and long sensing distance. It is widely used in equipment fault detection and location, oil and gas pipeline safety monitoring, large-scale structural health monitoring, and geological disaster monitoring and early warning. Furthermore, a slope-assisted Brillouin Optical Time Domain Analysis (SA-BOTDA) technique has been proposed.

[0003] However, due to the high power and steep slope of the optical signal used in SA-BOTDA technology, the phase-to-intensity noise converted from laser phase noise via the slope of the Brillouin gain spectrum is also strong. This can lead to errors in determining changes in temperature and / or strain, significantly degrading the signal-to-noise ratio of SA-BOTDA measurements. Furthermore, SA-BOTDA technology typically employs high Brillouin gain (gain > 30%). In this case, the Brillouin gain information carried by the photocurrent signal in the low-frequency sideband is far greater than the Brillouin attenuation information carried by the photocurrent signal in the high-frequency sideband. Directly differentiating the low-frequency and high-frequency sideband photocurrent signals does not effectively compensate for the phase-to-intensity noise, effectively preventing its impact.

[0004] Therefore, in real application scenarios, under high Brillouin gain conditions, suppressing the phase-to-intensity noise in SA-BOTDA technology and reducing the impact of laser linewidth on the signal-to-noise ratio have become important issues that need to be urgently addressed in the industry. Summary of the Invention

[0005] In response to the problems existing in the prior art, embodiments of the present application provide a method, device, and storage medium for measuring optical fiber temperature and / or strain.

[0006] In a first aspect, an embodiment of the present application provides a method for measuring optical fiber temperature and / or strain, comprising:

[0007] At any linear modulation frequency, a first high-frequency optical signal and a second low-frequency optical signal are obtained; the first high-frequency optical signal is the high-frequency portion of the detection optical signal obtained by transferring energy to the pulsed optical signal; the second low-frequency optical signal is the low-frequency portion of the detection optical signal obtained by transferring energy from the pulsed optical signal; the detection optical signal and the pulsed optical signal are generated by a laser with a preset linewidth; the linear modulation frequency is determined by the linear region of the Brillouin gain spectrum (BGS) or the linear region of the Brillouin loss spectrum (BLS) determined based on the slope-assisted Brillouin optical time-domain analysis (SA-BOTDA) technique;

[0008] converting the first high-frequency optical signal into a first electrical signal and the second low-frequency optical signal into a second electrical signal;

[0009] Determining, based on the central symmetry of a Brillouin gain spectrum BGS and a Brillouin loss spectrum BLS, an average value of a Brillouin attenuation value corresponding to the first electrical signal and a Brillouin gain value corresponding to the second electrical signal as a first average value;

[0010] Based on the Brillouin frequency shifts determined from all the first average values, a measurement result of the temperature and / or strain of the optical fiber to be measured is determined.

[0011] Optionally, determining the average value of the Brillouin attenuation value corresponding to the first electrical signal and the Brillouin gain value corresponding to the second electrical signal based on the central symmetry of the Brillouin gain spectrum BGS and the Brillouin loss spectrum BLS includes:

[0012] extracting, based on logarithmic normalization, a first Brillouin attenuation value corresponding to the first electrical signal and a second Brillouin gain value corresponding to the second electrical signal;

[0013] The first average value is determined based on an average value of the first Brillouin attenuation value and the second Brillouin gain value.

[0014] Optionally, the linear modulation frequency is determined by a linear region of a Brillouin gain spectrum BGS or a linear region of a Brillouin loss spectrum BLS determined based on a slope-assisted Brillouin optical time-domain analysis SA-BOTDA technique, and the corresponding method includes:

[0015] Based on SA-BOTDA technology, the Brillouin gain spectrum BGS and Brillouin loss spectrum BLS corresponding to the optical fiber under test are obtained;

[0016] Determining, based on the linear region of the Brillouin gain spectrum BGS or the linear region of the Brillouin loss spectrum BLS, a range of modulation frequencies corresponding to the detection light signal as a first frequency range;

[0017] Any frequency within the first frequency range is selected as the linear modulation frequency.

[0018] Optionally, determining a range of the modulation frequency corresponding to the detection light signal based on the linear region of the Brillouin gain spectrum BGS or the linear region of the Brillouin loss spectrum BLS includes:

[0019] Based on the distribution of the Brillouin gain spectrum BGS, determining a region that best conforms to the linear distribution as the linear region of the Brillouin gain spectrum BGS;

[0020] Based on the distribution of the Brillouin loss spectrum BLS, determining a region that best conforms to the linear distribution as the linear region of the Brillouin loss spectrum BLS;

[0021] Based on the linear region of the Brillouin gain spectrum BGS or the linear region of the Brillouin loss spectrum BLS and the frequency corresponding to the pulsed light signal, a range of the modulation frequency corresponding to the detection light signal is determined.

[0022] Optionally, determining the measurement result of the temperature and / or strain of the optical fiber to be measured based on the Brillouin frequency shift determined based on all the first average values ​​includes:

[0023] reconstructing the Brillouin gain spectrum based on the first average values ​​determined at all the linear modulation frequencies;

[0024] Based on the Brillouin frequency shift determined from the reconstructed Brillouin gain spectrum, a measurement result of the temperature and / or strain of the optical fiber to be measured is determined.

[0025] In a second aspect, an embodiment of the present application further provides a device for measuring optical fiber temperature and / or strain, comprising:

[0026] An acquisition module, configured to acquire a first high-frequency optical signal and a second low-frequency optical signal at any linear modulation frequency; the first high-frequency optical signal being the high-frequency portion of a probe optical signal obtained by transferring energy to a pulsed optical signal; and the second low-frequency optical signal being the low-frequency portion of a probe optical signal obtained by transferring energy from the pulsed optical signal; the probe optical signal and the pulsed optical signal being generated by a laser with a preset linewidth; and the linear modulation frequency being determined by a linear region of a Brillouin gain spectrum (BGS) or a linear region of a Brillouin loss spectrum (BLS) determined based on a slope-assisted Brillouin optical time-domain analysis (SA-BOTDA) technique.

[0027] a conversion module, configured to convert the first high-frequency optical signal into a first electrical signal and the second low-frequency optical signal into a second electrical signal;

[0028] a first determining module, configured to determine, based on the central symmetry of a Brillouin gain spectrum BGS and a Brillouin loss spectrum BLS, an average value of a Brillouin attenuation value corresponding to the first electrical signal and a Brillouin gain value corresponding to the second electrical signal as a first average value;

[0029] The second determination module is configured to determine a measurement result of the temperature and / or strain of the optical fiber to be measured based on the Brillouin frequency shifts determined from all the first average values.

[0030] Optionally, the first determining module is specifically configured to:

[0031] extracting, based on logarithmic normalization, a first Brillouin attenuation value corresponding to the first electrical signal and a second Brillouin gain value corresponding to the second electrical signal;

[0032] The first average value is determined based on an average value of the first Brillouin attenuation value and the second Brillouin gain value.

[0033] Optionally, the second determining module is specifically configured to:

[0034] reconstructing the Brillouin gain spectrum based on the first average values ​​determined at all the linear modulation frequencies;

[0035] Based on the Brillouin frequency shift determined from the reconstructed Brillouin gain spectrum, a measurement result of the temperature and / or strain of the optical fiber to be measured is determined.

[0036] In a third aspect, an embodiment of the present application further provides an electronic device, including a memory, a transceiver, and a processor;

[0037] A memory for storing a computer program; a transceiver for transmitting and receiving data under the control of the processor; and a processor for reading the computer program in the memory and implementing the method for measuring optical fiber temperature and / or strain as described in the first aspect above.

[0038] In a fourth aspect, an embodiment of the present application further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method for measuring optical fiber temperature and / or strain as described in the first aspect above.

[0039] In a fifth aspect, an embodiment of the present application further provides a processor-readable storage medium, wherein the processor-readable storage medium stores a computer program, and the computer program is used to enable the processor to execute the method for measuring optical fiber temperature and / or strain as described in the first aspect above.

[0040] In a sixth aspect, an embodiment of the present application further provides a communication device-readable storage medium, wherein the communication device-readable storage medium stores a computer program, and the computer program is used to enable the communication device to execute the optical fiber temperature and / or strain measurement method described in the first aspect above.

[0041] In a seventh aspect, an embodiment of the present application further provides a chip product readable storage medium, wherein the chip product readable storage medium stores a computer program, and the computer program is used to enable the chip product to execute the method for measuring optical fiber temperature and / or strain as described in the first aspect above.

[0042] In an eighth aspect, an embodiment of the present application further provides a computer program product, comprising a computer program, which, when executed by a processor, implements the method for measuring optical fiber temperature and / or strain as described in the first aspect above.

[0043] The method, device, and storage medium for measuring optical fiber temperature and / or strain provided in the embodiments of the present application utilize the central symmetry of BGS and BLS to convert the first high-frequency optical signal and the first low-frequency optical signal obtained by the original SA-BOTDA technology into electrical signals and then perform averaging processing. This suppresses the phase-to-intensity noise caused by the frequency shift of the first high-frequency optical signal and the first low-frequency optical signal affected by laser phase noise, and reconstructs the Brillouin gain spectrum, thereby reducing the impact of the laser linewidth on the signal-to-noise ratio and improving the accuracy of optical fiber temperature and / or strain measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the present application or the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0045] Figure 1(a) is a schematic diagram of the principle of implementing BOTDA by a single laser;

[0046] Figure 1(b) is a schematic diagram of the distribution of laser phase noise along the optical fiber in the BOTDA technology;

[0047] Figure 2 Schematic diagram of the effect of laser phase noise on the measured Brillouin gain;

[0048] Figure 3 This is a schematic diagram of the change in Brillouin gain caused by the change in the detection light frequency when the detection light frequency is at different positions of the BGS;

[0049] Figure 4 This is a schematic diagram of the relationship between the detection light frequency and the laser phase transition intensity noise;

[0050] Figure 5 This is a schematic diagram of the basic principle of traditional SA-BOTDA measurement of dynamic strain;

[0051] Figure 61 is a flow chart of a method for measuring optical fiber temperature and / or strain provided in an embodiment of the present application;

[0052] Figure 7 1 is a schematic diagram of the corresponding results of the laser phase noise and the measured Brillouin gain and Brillouin attenuation values ​​provided in an embodiment of the present application;

[0053] Figure 8 This is a schematic diagram of the system structure for implementing the method for measuring optical fiber temperature and / or strain provided in an embodiment of the present application;

[0054] Figure 9 1 is a schematic structural diagram of an optical fiber temperature and / or strain measurement device provided in an embodiment of the present application;

[0055] Figure 10 This is a structural diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0056] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in 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.

[0057] In order to facilitate a clearer understanding of the various embodiments of the present application, some relevant background knowledge is first introduced as follows.

[0058] Traditional BOTDA technology uses a laser-generated pulsed light (pump pulse) and a probe light beam, which enter the fiber at opposite ends and propagate in opposite directions. At each location in the fiber, the pump pulse and the counter-propagating continuous probe light phase-match each other to excite local acoustic waves, resulting in stimulated Brillouin scattering (SBS). The intensity of SBS depends on the energy of the pulse light and the frequency difference between the pulse and probe light. To stabilize the jitter of the frequency difference between the two beams to within 1 MHz and improve measurement accuracy, a single laser is typically used for external modulation to generate the pulse light and probe light, as shown in Figure 1(a).

[0059] When the pulse and the probe light meet at different positions in the optical fiber, there will be a phase difference due to the difference in optical path, which will inevitably be affected by the laser phase noise. In BOTDA technology, the change of the laser phase is a stationary random process, and the phase noise is a function of the laser line width and the fiber position. The laser line width is used to indicate the fluctuation range of the laser frequency emitted by the laser. The fiber position indicates the point where the pulse light and the probe light meet in the optical fiber. Assuming that the optical path of the pulse and the probe light from the laser to the two ends of the optical fiber is the same, the optical path difference in the middle position of the optical fiber is 0, and the phase difference and the corresponding jitter are the smallest; gradually approaching the two ends of the optical fiber, the optical path difference increases, and the phase difference and the corresponding jitter also increase accordingly, as shown in Figure 1(b), where the horizontal axis represents the optical path difference, the vertical axis δφ in the upper half represents the phase difference, and the vertical axis in the lower half represents the phase difference. represents the variance of the phase difference. The different lines in the upper half represent the phase difference in multiple samplings. This distribution of phase differences means that at each fiber location, the phonons excited by the phase matching between the pulse and probe light in multiple samplings are different, resulting in jitter in the corresponding measured Brillouin gain.

[0060] This fluctuation of the Brillouin gain at each position in the fiber during multiple samplings, caused by laser phase noise, is called phase-to-intensity noise. The noise distribution is related to the fiber position, and the noise level still depends on the laser linewidth and the optical path difference between the pulse and the probe light. Under the condition that the laser linewidth and fiber position are known, the magnitude of the phase-to-intensity noise is related to the position of the probe light frequency on the BGS (Brillouin Gain Spectrum) and BLS (Brillouin Loss Spectrum). Taking BGS as an example, the analysis assumes that the pulse frequency v p remains unchanged, while the frequency ν of the detection light s =ν c -v sw Affected by the laser phase noise, v c and v sw represent the carrier frequency and modulation frequency of the detection light respectively. Figure 2 (a) is used to represent the Brillouin gain measured when the laser has no phase noise. Figure 2 (b) and (c) are used to represent the Brillouin gain measured when the laser has phase noise, v c Indicates the carrier frequency, v sw Indicates the modulation frequency. Figure 2 As shown in (a), when the laser has no phase noise, v c =v p , the frequency difference between the pulse and the probe light Δν=v sw , the detection light frequency is used as the reference frequency. Figure 2(b) and (c) represent the stimulated Brillouin scattering (SBS) between the probe light and the pulse light, that is, the energy transfer occurs. The frequency of the probe light v s The frequency shift δv is generated relative to the reference frequency due to the influence of laser phase noise, resulting in a frequency difference between the pulse and the probe light. This generates a change in Brillouin gain (g1→g2, g1→g3), which in turn generates phase-to-intensity noise.

[0061] Figure 3 This is a schematic diagram of the Brillouin gain change caused by the change in the detection light frequency when the detection light frequency is at different positions of the BGS, as shown in Figure 3 As shown, the detection light frequency v s The Brillouin gain change Δg caused by jitter is related to the position of the probe light frequency on the BGS. The part of the vertical stripe filled area represents the jitter v″′ of the probe light frequency. s The resulting Brillouin gain change Δg is minimal, and the area filled with slashes represents the frequency jitter v′ of the probe light. s The Brillouin gain change Δg caused by this is the smallest, and the grid-filled area represents the probe light frequency v s Jitter v″ s The resulting Brillouin gain change Δg is the largest.

[0062] Figure 4 This is a diagram showing the relationship between the detection light frequency and the laser phase transition intensity noise. Figure 4 The laser phase-to-intensity noise generated when the detection light frequency is at different positions of the BGS and the interval of frequency jitter of the detection light frequency is the same is shown. The magnitude of the laser phase-to-intensity noise is related to the slope of the Brillouin spectrum. Figure 3 The slope is the smallest and the phase-to-intensity noise is the smallest, while near the linear region (corresponding to the part of the vertical stripe filling area) Figure 3 The slope of the BGS linear region is the largest, and the phase-to-intensity noise is the largest. Furthermore, since the measured Brillouin gain spectrum is determined by the convolution of the pulse's power spectral density and the Brillouin eigenspectrum, the longer the pulse width, the greater the slope of the measured BGS linear region and the greater the phase-to-intensity noise.

[0063] The slope-assisted Brillouin optical time-domain analysis (SA-BOTDA) technique uses changes in the gain of the BGS linear region to determine changes in the Brillouin frequency shift (BFS), thereby demodulating temperature strain. In this technique, phase-to-intensity noise can affect BFS determination and lead to measurement errors.

[0064] The traditional direct detection SA-BOTDA technology fixes the frequency difference between the pump pulse light and the probe light in the quasi-linear region of the Brillouin gain spectrum, and uses the slope of this linear region to directly convert the change of Brillouin gain into the change of Brillouin frequency shift, thereby sensing dynamic strain. The basic principle of traditional SA-BOTDA for measuring dynamic strain is as follows: Figure 5 As shown in Figure 1. Assuming the fiber is stationary (reference state), the BGS corresponding to a given fiber position is represented by a dotted line. When the frequency difference v0 between the pump pulse and the probe light is at the center of the BGS slope, the corresponding Brillouin gain is g0, and the slope is K. When temperature or strain changes, the BGS shifts to the right, as represented by the solid line. The Brillouin gain corresponding to v0 is g1, and the difference from the reference Brillouin gain is Δg = g1 - g0. Simple mathematical relationships show that when the BGS shifts, the corresponding frequency shift is ΔBFS = Δg / K.

[0065] Ideally, the frequency difference between the pump pulse light and the probe light in SA-BOTDA is always a predefined fixed value, such as Figure 5 v0 in the optical fiber. However, in SA-BOTDA, the pump pulse light and the probe light are emitted by the same light source (laser), transmitted through different paths, and meet at various locations in the optical fiber. The optical path difference between the pump pulse light and the probe light at most locations in the optical fiber is not zero, and the laser phase noise causes the frequency difference between the pump pulse light and the probe light to be unstable. This phenomenon is equivalent to the probe light frequency being constant while the pump pulse light frequency fluctuates. In traditional direct detection SA-BOTDA technology, due to the high optical signal power and large slope, the signal intensity noise (i.e., phase-to-intensity noise) converted from the laser phase noise through the slope of the Brillouin gain spectrum is also strong. In addition, temperature and strain can cause the Brillouin gain spectrum to drift, and phase-to-intensity noise can also cause the Brillouin gain spectrum to drift. In this case, the strain or temperature change determined may be interfered by the phase-to-intensity noise, which will lead to errors in the calculation of strain or temperature changes.

[0066] In addition, SA-BOTDA technology usually adopts high Brillouin gain (>30%). In this case, the photocurrent signal of the low-frequency sideband (carrying Brillouin gain information) is much larger than the photocurrent signal of the high-frequency sideband (carrying Brillouin attenuation information). Directly differential processing the photocurrent signal of the high-frequency sideband and the photocurrent signal of the low-frequency sideband cannot effectively separate the actual Brillouin gain information and Brillouin attenuation information, and cannot effectively compensate for the phase-to-intensity noise.

[0067] Therefore, the present application improves the existing SA-BOTDA technology and proposes that the photocurrent signals of the high and low sidebands obtained in the existing SA-BOTDA technology are not directly differentiated, but are first photoelectrically converted separately. This is conducive to extracting the actual Brillouin gain information and Brillouin attenuation information, and can effectively suppress the phase-to-intensity noise in the SA-BOTDA technology, improve the signal-to-noise ratio, and thereby improve the accuracy of optical fiber temperature and / or strain measurement based on the improved SA-BOTDA technology.

[0068] Figure 6 FIG. 1 is a flow chart of a method for measuring optical fiber temperature and / or strain provided in an embodiment of the present application; FIG. Figure 6 As shown, the method includes:

[0069] Step 601: Acquire a first high-frequency optical signal and a second low-frequency optical signal at any linear modulation frequency; the first high-frequency optical signal is the high-frequency portion of a probe optical signal obtained by transferring energy to a pulsed optical signal; the second low-frequency optical signal is the low-frequency portion of the probe optical signal obtained by transferring energy from the pulsed optical signal; the probe optical signal and the pulsed optical signal are generated by a laser with a preset linewidth; the linear modulation frequency is determined by a linear region of a Brillouin gain spectrum (BGS) or a linear region of a Brillouin loss spectrum (BLS) determined based on a slope-assisted Brillouin optical time-domain analysis (SA-BOTDA) technique;

[0070] Step 602: Convert the first high-frequency optical signal into a first electrical signal, and convert the second low-frequency optical signal into a second electrical signal;

[0071] Step 603: Based on the central symmetry of the Brillouin gain spectrum BGS and the Brillouin loss spectrum BLS, determine an average value of the Brillouin attenuation value corresponding to the first electrical signal and the Brillouin gain value corresponding to the second electrical signal as a first average value;

[0072] Step 604: Determine the measurement result of the temperature and / or strain of the optical fiber to be measured based on the Brillouin frequency shifts determined from all the first average values.

[0073] Specifically, in most BOTDA systems, the probe light is generally double-sideband modulated. In order to suppress the non-local effect by performing double-sideband modulation of the probe light with suppressed carrier, two processes, Brillouin amplification (low-frequency sideband of the probe light) and Brillouin attenuation (high-frequency sideband of the probe light), occur simultaneously at each position in the sensing fiber. The frequency of the pulsed light signal is represented by v p The frequency of the high-frequency sideband of the detection optical signal is expressed as The frequency of the low-frequency sideband of the detection optical signal is expressed as Indicates that, v c Indicates the carrier frequency, v swIndicates the modulation frequency.

[0074] To simplify the analysis, assume that the frequency of the pulse light signal v p The frequency of the high-frequency sideband of the detected optical signal remains unchanged. and the frequency of the low-frequency sideband It will be affected by the phase noise of the laser. Assuming that the laser has no phase noise, such as Figure 7 As shown in (a), the frequency of the pulse light signal is v p , the frequency difference between the two sidebands of the pulse light signal and the detection light signal is equal (Δv L =Δv G =v sw ), the absolute values ​​of the measured Brillouin attenuation and Brillouin gain are the same At this time, the frequencies of the two sidebands of the detection light are used as reference frequencies.

[0075] When the high-frequency sideband of the detected light and low-frequency sidebands Affected by the laser phase noise, the frequencies are shifted to the right by δv relative to their respective reference frequencies, as shown in Figure 7 As shown in (b), the Brillouin attenuation and Brillouin gain values ​​change. At this time, the frequency differences between the high and low frequency sidebands of the pulse light signal and the detection light signal are and The average value of the two frequency differences is constant at v sw Since the Brillouin gain spectrum BGS and Brillouin loss spectrum BLS are Lorentz type and have central symmetry, the sum of the Brillouin attenuation value and the Brillouin gain value when the high and low frequency sidebands of the detection light interact with the pulse light signal through stimulated Brillouin scattering SBS remains constant, and its average value is Independent of phase-to-intensity noise.

[0076] When the high and low frequency sidebands of the detection light are shifted to the left by δv, as Figure 7 As shown in (c), the analysis process is the same as Figure 7 Same as (b), the average value of the Brillouin attenuation and Brillouin gain values ​​collected at the same time It is also independent of the phase-to-intensity noise. According to the above analysis, the frequency of the detection light signal at other positions on the Brillouin spectrum meets the above characteristics.

[0077] On this basis, the present application proposes a method for measuring optical fiber temperature and / or strain to effectively suppress phase-to-intensity noise and improve the signal-to-noise ratio of the SA-BOTDA technology.

[0078] The linear modulation frequency range is determined based on the linear region of the Brillouin gain spectrum BGS or the linear region of the Brillouin loss spectrum BLS determined based on the slope-assisted Brillouin optical time-domain analysis SA-BOTDA technology. Within the range, one of the linear modulation frequencies is selected in sequence to obtain a high-frequency portion of the detection optical signal obtained after energy is transferred to the pulsed optical signal as the first high-frequency optical signal, and a low-frequency portion of the detection optical signal obtained after energy is transferred from the pulsed optical signal as the second low-frequency optical signal.

[0079] The first high-frequency optical signal and the second low-frequency optical signal are converted into a first electrical signal and a second electrical signal respectively. Specifically, a photodiode (PD), also known as a photoelectric converter, can be used to convert the optical signal into the electrical signal.

[0080] The central symmetry of BGS and BLS is used to determine the Brillouin gain value carried by the first electrical signal and the Brillouin attenuation value carried by the second electrical signal, respectively. The two values ​​are averaged to obtain a first average value of the current sampling data. This effectively suppresses fluctuations in the laser's phase noise during multiple samplings of the Brillouin gain value, effectively suppressing phase-to-intensity noise.

[0081] Since full-frequency sweep measurement is required in SA-BOTDA to calibrate the Brillouin frequency shift (BFS) at each position of the optical fiber, the modulation frequency of the detection light signal needs to be changed and the above process repeated. The Brillouin gain values ​​at all linear modulation frequencies within the range of the linear modulation frequency are obtained, and then the corresponding Brillouin frequency shift is determined. The change in the temperature and / or strain of the optical fiber is linearly related to the change in the Brillouin frequency shift, and the temperature and / or strain measurement results of the optical fiber to be measured can be determined.

[0082] The method for measuring optical fiber temperature and / or strain provided in an embodiment of the present application utilizes the central symmetry of BGS and BLS to convert the first high-frequency optical signal and the first low-frequency optical signal obtained by the original SA-BOTDA technology into electrical signals and then perform averaging processing. This suppresses the phase-to-intensity noise caused by the frequency shift of the first high-frequency optical signal and the first low-frequency optical signal affected by the laser phase noise, and reconstructs the Brillouin gain spectrum, thereby reducing the impact of the laser linewidth on the signal-to-noise ratio and improving the accuracy of the temperature and / or strain measurement of the optical fiber.

[0083] Optionally, determining the average value of the Brillouin attenuation value corresponding to the first electrical signal and the Brillouin gain value corresponding to the second electrical signal based on the central symmetry of the Brillouin gain spectrum BGS and the Brillouin loss spectrum BLS includes:

[0084] extracting, based on logarithmic normalization, a first Brillouin attenuation value corresponding to the first electrical signal and a second Brillouin gain value corresponding to the second electrical signal;

[0085] The first average value is determined based on an average value of the first Brillouin attenuation value and the second Brillouin gain value.

[0086] Specifically, the Brillouin gain spectrum BGS and the Brillouin loss spectrum BLS are Lorentzian and have centrosymmetry.

[0087] For a given laser linewidth and a given probe light frequency position on the BGS, two identical photodiodes (PDs) are used to simultaneously acquire the photocurrent signals of the high and low frequency sidebands. The nth acquired signal can be expressed as:

[0088]

[0089] Among them, I G (z,v sw , n) represents the first electrical signal, I L (z,v sw , n) represents the second electrical signal, z represents any position of the optical fiber, and also represents the position where the detection light signal and the pulse signal meet in the optical fiber to be tested, v sw represents the modulation frequency of the detection light, n represents the number of sampling times, η1 and η2 are the responsivities of the photodiode PD1 and the photodiode PD2, assuming that they are approximately the same and satisfy η1≈η2≈1A / W; g represents the DC power of the detection light reaching the photodiode PD1 or photodiode PD2; G and g L They represent the Brillouin gain value corresponding to the low-frequency sideband of the detection light and the Brillouin attenuation value corresponding to the high-frequency sideband of the detection light, respectively, and exp[] represents an exponential function with the natural constant e as the base.

[0090] If the first electrical signal and the second electrical signal are directly differentiated and the Brillouin gain value carried therein is obtained, the Brillouin gain value or Brillouin attenuation value cannot be effectively obtained, and thus the influence of the phase-to-intensity noise cannot be effectively compensated.

[0091] The present application first applies logarithmic normalization to the first and second electrical signals, effectively extracting the Brillouin attenuation and gain values ​​carried therein. Furthermore, by averaging these extracted Brillouin attenuation and gain values, the application effectively suppresses phase-to-intensity noise, i.e., suppresses fluctuations in the Brillouin attenuation and gain values ​​over multiple measurements. This allows the ultimately determined first average value to more accurately reflect the distribution of the Brillouin gain spectrum, thereby facilitating the accurate determination of the Brillouin gain spectrum.

[0092] Optionally, the linear modulation frequency is determined by a linear region of a Brillouin gain spectrum BGS or a linear region of a Brillouin loss spectrum BLS determined based on a slope-assisted Brillouin optical time-domain analysis SA-BOTDA technique, and the corresponding method includes:

[0093] Based on SA-BOTDA technology, the Brillouin gain spectrum BGS and Brillouin loss spectrum BLS corresponding to the optical fiber under test are obtained;

[0094] Determining, based on the linear region of the Brillouin gain spectrum BGS or the linear region of the Brillouin loss spectrum BLS, a range of modulation frequencies corresponding to the detection light signal as a first frequency range;

[0095] Any frequency within the first frequency range is selected as the linear modulation frequency.

[0096] Specifically, based on the SA-BOTDA technique, after obtaining the Brillouin gain spectrum (BGS) and Brillouin loss spectrum (BLS) corresponding to the optical fiber under test, the linear region of the BGS or the linear region of the BLS is determined. Since the BGS and BLS are centrosymmetric, the linear regions of the BGS and BLS are usually also centrosymmetric.

[0097] The linear region of BGS is mainly used as an example for explanation. Based on the distribution of the Brillouin gain spectrum BGS, the region that best matches the linear distribution is determined as the linear region of the Brillouin gain spectrum BGS. The minimum and maximum frequencies corresponding to this linear region are determined, which is equivalent to determining the maximum and minimum frequencies of the detection light signal.

[0098] Since BGS and BLS are centrosymmetric, the frequency of the symmetry center is taken as the frequency of the pulse light signal. For the sake of simplicity of analysis, it is assumed that the frequency of the pulse light signal in BGS is v p remains unchanged, while the frequency v of the detection light signal s =v c -v sw Affected by the laser phase noise, the frequency v of the pulse light signal is changed. p is the carrier frequency v of the detection optical signal c , after determining the maximum and minimum values ​​of the detection light signal frequency, and formula v s =v c -v sw The first frequency range is determined, i.e., the modulation frequency range corresponding to the detection optical signal when in the linear region of the Brillouin gain spectrum (BGS). Within this first frequency range, a frequency value is sequentially selected as the linear modulation frequency to obtain a first high-frequency optical signal and a second low-frequency optical signal, thereby determining the temperature and / or strain measurement results of the optical fiber under test.

[0099] The linear region of the BLS can be implemented similarly to the linear region of the BGS. That is, the modulation frequency range corresponding to the detection light signal can be determined based on the linear region corresponding to the BGS, or the modulation frequency range corresponding to the detection light signal can be determined based on the linear region corresponding to the BLS. This implementation method is flexible and easy to implement.

[0100] Optionally, determining the measurement result of the temperature and / or strain of the optical fiber to be measured based on the Brillouin frequency shift determined based on all the first average values ​​includes:

[0101] reconstructing the Brillouin gain spectrum based on the first average values ​​determined at all the linear modulation frequencies;

[0102] Based on the Brillouin frequency shift determined from the reconstructed Brillouin gain spectrum, a measurement result of the temperature and / or strain of the optical fiber to be measured is determined.

[0103] Specifically, after determining the value range of the modulation frequency corresponding to the detection light signal that satisfies the linear region of the Brillouin gain spectrum in the above manner, the first average value is determined at any linear modulation frequency within the range in turn to reconstruct the Brillouin gain spectrum.

[0104] By using changes in the BGS linear region gain to determine changes in the Brillouin frequency shift (BFS), and since changes in fiber temperature and strain are linearly related to changes in the Brillouin frequency shift, the temperature and / or strain measurements of the fiber under test can be determined. This allows the user to determine where temperature or strain anomalies exist on the fiber under test, such as where along the fiber abruptly experiences a significant temperature fluctuation or where a significant impact has altered the fiber's stress. This allows for the detection and location of fiber faults, facilitating timely repair measures.

[0105] The method for measuring optical fiber temperature and / or strain provided in an embodiment of the present application utilizes the central symmetry of BGS and BLS to convert the first high-frequency optical signal and the first low-frequency optical signal obtained by the original SA-BOTDA technology into electrical signals and then perform averaging processing. This suppresses the phase-to-intensity noise caused by the frequency shift of the first high-frequency optical signal and the first low-frequency optical signal affected by the laser phase noise, and reconstructs the Brillouin gain spectrum, thereby reducing the impact of the laser linewidth on the signal-to-noise ratio and improving the accuracy of the temperature and / or strain measurement of the optical fiber.

[0106] The following describes the method for measuring optical fiber temperature and / or strain provided by the present application with reference to specific examples.

[0107] Figure 8 FIG. 1 is a schematic diagram of a system structure for implementing the method for measuring optical fiber temperature and / or strain provided in an embodiment of the present application. Figure 8As shown, the structure within the dashed box is the same as that of the existing SA-BOTDA system. The circulator 2, grating 1, circulator 3, grating 2, photodetector 1, photodetector 2, and signal acquisition outside the dashed box are the improved parts made by this application. This improved part receives the optical signal output from the circulator 1 and performs further processing by the improved part, specifically including:

[0108] At any modulation frequency ν sw Under the given laser linewidth and the given position of the probe light frequency on the BGS, the pulse light signal transmitted in the optical fiber to be tested and the double-sideband probe light signal after energy transfer from the probe light signal are output from circulator 1, including the high-frequency sideband light signal after energy transfer and the low-frequency sideband light signal after energy transfer. The high-frequency sideband light signal after energy transfer is the light signal after energy transfer from the original high-frequency probe light signal to the pulse light signal, and the low-frequency sideband light signal after energy transfer is the light signal after energy is obtained from the pulse light signal. The required light signals are filtered out by grating 1 and grating 2 respectively. For example, grating 1 filters out the high-frequency sideband light signal after energy transfer, reflects the high-frequency sideband light signal after energy transfer to the corresponding circulator 2, and transmits it to the photodetector 1. Then, grating 2 filters out the low-frequency sideband light signal after energy transfer, reflects the low-frequency sideband light signal after energy transfer to the corresponding circulator 3, and transmits it to the photodetector 2. Of course, the grating 2 can also be used to filter out the high-frequency sideband optical signal after the energy transfer, and the corresponding grating 1 can be used to filter out the low-frequency sideband optical signal after the energy transfer.

[0109] Among them, photodetector 1 and photodetector 2 are the same. The photocurrent signals of the high and low frequency sidebands of the detection light after n energy transfers are collected at the same time. Logarithmic normalization is used to extract the Brillouin gain value g of the high and low frequency sidebands of the detection light respectively. G (low-frequency sideband of the detection light) and attenuation value g L (detection light high-frequency sideband), and average the extracted Brillouin gain and attenuation values. This ensures that the final Brillouin gain value does not change with the number of sampling times, that is, the Brillouin gain value is only related to the modulation frequency of the detection light signal and is not affected by the laser phase noise. In order to obtain the BFS at each position of the optical fiber at different frequencies, it is necessary to adjust the modulation frequency of the detection light signal, fix the modulation frequency in the linear region of the Brillouin spectrum, and continue to repeat the above process. The entire measurement process does not require any changes to the system structure. Under the conditions of a given laser linewidth and high Brillouin gain, the above-mentioned balanced detection technology based on post-processing can reduce the impact of laser phase noise on the SA-BOTDA system, and is an effective means to achieve the optimal signal-to-noise ratio of the system.

[0110] Figure 9 FIG. 1 is a schematic diagram of a device for measuring optical fiber temperature and / or strain provided in an embodiment of the present application. Figure 9 As shown, the device includes:

[0111] Acquisition module 901 is configured to acquire a first high-frequency optical signal and a second low-frequency optical signal at any linear modulation frequency; the first high-frequency optical signal is the high-frequency portion of a probe optical signal obtained by transferring energy to a pulsed optical signal; the second low-frequency optical signal is the low-frequency portion of a probe optical signal obtained by transferring energy from the pulsed optical signal; the probe optical signal and the pulsed optical signal are generated by a laser with a preset linewidth; the linear modulation frequency is determined by a linear region of a Brillouin gain spectrum (BGS) or a linear region of a Brillouin loss spectrum (BLS) determined using a slope-assisted Brillouin optical time-domain analysis (SA-BOTDA) technique;

[0112] a conversion module 902, configured to convert the first high-frequency optical signal into a first electrical signal and the second low-frequency optical signal into a second electrical signal;

[0113] A first determining module 903 is configured to determine, based on the central symmetry of a Brillouin gain spectrum BGS and a Brillouin loss spectrum BLS, an average value of a Brillouin attenuation value corresponding to the first electrical signal and a Brillouin gain value corresponding to the second electrical signal as a first average value;

[0114] The second determining module 904 is configured to determine a measurement result of the temperature and / or strain of the optical fiber to be measured based on the Brillouin frequency shifts determined from all the first average values.

[0115] Optionally, the first determining module 903 is specifically configured to:

[0116] extracting, based on logarithmic normalization, a first Brillouin attenuation value corresponding to the first electrical signal and a second Brillouin gain value corresponding to the second electrical signal;

[0117] The first average value is determined based on an average value of the first Brillouin attenuation value and the second Brillouin gain value.

[0118] Optionally, the second determining module 904 is specifically configured to:

[0119] reconstructing the Brillouin gain spectrum based on the first average values ​​determined at all the linear modulation frequencies;

[0120] Based on the Brillouin frequency shift determined from the reconstructed Brillouin gain spectrum, a measurement result of the temperature and / or strain of the optical fiber to be measured is determined.

[0121] Specifically, the above-mentioned optical fiber temperature and / or strain measurement device provided in the embodiment of the present application can implement all the method steps implemented in the above-mentioned method embodiment and can achieve the same technical effect. The parts and beneficial effects of this embodiment that are the same as those in the method embodiment will not be described in detail here.

[0122] Figure 10 is a structural diagram of an electronic device provided in an embodiment of the present application; Figure 10 As shown, the electronic device includes a processor 1010, a communication interface 1020, a memory 1030, and a communication bus 1040, wherein the processor 1010, the communication interface 1020, and the memory 1030 communicate with each other via the communication bus 1040. The processor 1010 can call the logic instructions in the memory 1030 to execute any of the methods for measuring optical fiber temperature and / or strain provided in the above embodiments, for example:

[0123] At any linear modulation frequency, a first high-frequency optical signal and a second low-frequency optical signal are obtained; the first high-frequency optical signal is the high-frequency portion of the detection optical signal obtained by transferring energy to the pulsed optical signal; the second low-frequency optical signal is the low-frequency portion of the detection optical signal obtained by transferring energy from the pulsed optical signal; the detection optical signal and the pulsed optical signal are generated by a laser with a preset linewidth; the linear modulation frequency is determined by the linear region of the Brillouin gain spectrum (BGS) or the linear region of the Brillouin loss spectrum (BLS) determined based on the slope-assisted Brillouin optical time-domain analysis (SA-BOTDA) technique;

[0124] converting the first high-frequency optical signal into a first electrical signal and the second low-frequency optical signal into a second electrical signal;

[0125] Determining, based on the central symmetry of a Brillouin gain spectrum BGS and a Brillouin loss spectrum BLS, an average value of a Brillouin attenuation value corresponding to the first electrical signal and a Brillouin gain value corresponding to the second electrical signal as a first average value;

[0126] Based on the Brillouin frequency shifts determined from all the first average values, a measurement result of the temperature and / or strain of the optical fiber to be measured is determined.

[0127] In addition, the logic instructions in the above-mentioned memory 1030 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when sold or used as an independent product. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0128] It should be noted here that the above-mentioned electronic device provided in the embodiment of the present application can implement all the method steps implemented in the above-mentioned method embodiment and can achieve the same technical effect. The parts and beneficial effects of this embodiment that are the same as those in the method embodiment will not be described in detail here.

[0129] On the other hand, an embodiment of the present application further provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium, and the computer program includes program instructions. When the program instructions are executed by a computer, the computer can perform the optical fiber temperature and / or strain measurement methods provided in the above embodiments.

[0130] On the other hand, an embodiment of the present application further provides a processor-readable storage medium, wherein the processor-readable storage medium stores a computer program, and the computer program is used to enable the processor to execute the optical fiber temperature and / or strain measurement method provided by the above embodiments.

[0131] The processor-readable storage medium can be any available medium or data storage device that can be accessed by the processor, including but not limited to magnetic storage (such as floppy disks, hard disks, magnetic tapes, magneto-optical disks (MO)), optical storage (such as CDs, DVDs, BDs, HVDs, etc.), and semiconductor storage (such as ROMs, EPROMs, EEPROMs, non-volatile memories (NANDFLASH), solid-state drives (SSDs)), etc.

[0132] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in one location or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of the present embodiment. Persons of ordinary skill in the art will be able to understand and implement the present invention without inventive effort.

[0133] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, or of course, by hardware. Based on this understanding, the essence of the above technical solution or the part that contributes to the existing technology can be embodied in the form of a software product. The computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or certain parts of the embodiments.

[0134] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for measuring optical fiber temperature and / or strain, characterized in that: include: Under any linear modulation frequency, obtaining a first high-frequency optical signal and a second low-frequency optical signal; The first high-frequency optical signal is a high-frequency portion of a detection optical signal obtained by transferring energy to a pulsed optical signal; the second low-frequency optical signal is a low-frequency portion of a detection optical signal obtained by transferring energy from a pulsed optical signal; the detection optical signal and the pulsed optical signal are generated by a laser with a preset linewidth; the linear modulation frequency is determined by a linear region of a Brillouin gain spectrum (BGS) or a linear region of a Brillouin loss spectrum (BLS) determined based on a slope-assisted Brillouin optical time-domain analysis (SA-BOTDA) technique, and the corresponding method includes: Based on the slope-assisted Brillouin optical time-domain analysis (SA-BOTDA) technology, the Brillouin gain spectrum (BGS) and Brillouin loss spectrum (BLS) corresponding to the optical fiber under test are obtained; Determining a modulation frequency range corresponding to the detection light signal based on a linear region of the Brillouin gain spectrum BGS or a linear region of the Brillouin loss spectrum BLS as a first frequency range includes: Based on the distribution of the Brillouin gain spectrum BGS, determining a region that best conforms to the linear distribution as the linear region of the Brillouin gain spectrum BGS; Based on the distribution of the Brillouin loss spectrum BLS, determining a region that best conforms to the linear distribution as the linear region of the Brillouin loss spectrum BLS; Determining a range of a modulation frequency corresponding to the detection light signal based on a linear region of the Brillouin gain spectrum BGS or a linear region of the Brillouin loss spectrum BLS and a frequency corresponding to the pulsed light signal; Selecting any frequency within the first frequency range as the linear modulation frequency; converting the first high-frequency optical signal into a first electrical signal and the second low-frequency optical signal into a second electrical signal; Determining, based on the central symmetry of a Brillouin gain spectrum BGS and a Brillouin loss spectrum BLS, an average value of a Brillouin attenuation value corresponding to the first electrical signal and a Brillouin gain value corresponding to the second electrical signal as a first average value; Based on the Brillouin frequency shifts determined from all the first average values, a measurement result of the temperature and / or strain of the optical fiber to be measured is determined.

2. The method for measuring optical fiber temperature and / or strain according to claim 1, characterized in that: The determining, based on the central symmetry of the Brillouin gain spectrum BGS and the Brillouin loss spectrum BLS, an average value of the Brillouin attenuation value corresponding to the first electrical signal and the Brillouin gain value corresponding to the second electrical signal includes: extracting, based on logarithmic normalization, a first Brillouin attenuation value corresponding to the first electrical signal and a second Brillouin gain value corresponding to the second electrical signal; The first average value is determined based on an average value of the first Brillouin attenuation value and the second Brillouin gain value.

3. The method for measuring optical fiber temperature and / or strain according to claim 1, wherein: Determining the measurement result of the temperature and / or strain of the optical fiber to be measured based on the Brillouin frequency shift determined by all the first average values ​​includes: reconstructing the Brillouin gain spectrum based on the first average values ​​determined at all the linear modulation frequencies; Based on the Brillouin frequency shift determined from the reconstructed Brillouin gain spectrum, a measurement result of the temperature and / or strain of the optical fiber to be measured is determined.

4. An optical fiber temperature and / or strain measurement device, characterized in that: include: An acquisition module, configured to acquire a first high-frequency optical signal and a second low-frequency optical signal at any linear modulation frequency; The first high-frequency optical signal is a high-frequency portion of a detection optical signal obtained by transferring energy to a pulsed optical signal; the second low-frequency optical signal is a low-frequency portion of a detection optical signal obtained by transferring energy from a pulsed optical signal; the detection optical signal and the pulsed optical signal are generated by a laser with a preset linewidth; the linear modulation frequency is determined by a linear region of a Brillouin gain spectrum (BGS) or a linear region of a Brillouin loss spectrum (BLS) determined based on a slope-assisted Brillouin optical time-domain analysis (SA-BOTDA) technique, and the corresponding method includes: Based on the slope-assisted Brillouin optical time-domain analysis (SA-BOTDA) technology, the Brillouin gain spectrum (BGS) and Brillouin loss spectrum (BLS) corresponding to the optical fiber under test are obtained; Determining a modulation frequency range corresponding to the detection light signal based on a linear region of the Brillouin gain spectrum BGS or a linear region of the Brillouin loss spectrum BLS as a first frequency range includes: Based on the distribution of the Brillouin gain spectrum BGS, determining a region that best conforms to the linear distribution as the linear region of the Brillouin gain spectrum BGS; Based on the distribution of the Brillouin loss spectrum BLS, determining a region that best conforms to the linear distribution as the linear region of the Brillouin loss spectrum BLS; Determining a range of a modulation frequency corresponding to the detection light signal based on a linear region of the Brillouin gain spectrum BGS or a linear region of the Brillouin loss spectrum BLS and a frequency corresponding to the pulsed light signal; Selecting any frequency within the first frequency range as the linear modulation frequency; a conversion module, configured to convert the first high-frequency optical signal into a first electrical signal and the second low-frequency optical signal into a second electrical signal; a first determining module, configured to determine, based on the central symmetry of a Brillouin gain spectrum BGS and a Brillouin loss spectrum BLS, an average value of a Brillouin attenuation value corresponding to the first electrical signal and a Brillouin gain value corresponding to the second electrical signal as a first average value; The second determination module is configured to determine a measurement result of the temperature and / or strain of the optical fiber to be measured based on the Brillouin frequency shifts determined from all the first average values.

5. The optical fiber temperature and / or strain measurement device according to claim 4, characterized in that: The first determining module is specifically configured to: extracting, based on logarithmic normalization, a first Brillouin attenuation value corresponding to the first electrical signal and a second Brillouin gain value corresponding to the second electrical signal; The first average value is determined based on an average value of the first Brillouin attenuation value and the second Brillouin gain value.

6. The optical fiber temperature and / or strain measurement device according to claim 4, characterized in that: The second determining module is specifically configured to: reconstructing the Brillouin gain spectrum based on the first average values ​​determined at all the linear modulation frequencies; Based on the Brillouin frequency shift determined from the reconstructed Brillouin gain spectrum, a measurement result of the temperature and / or strain of the optical fiber to be measured is determined.

7. An electronic device, characterized in that: Including memory, transceiver, processor; Memory for storing computer programs; a transceiver, configured to transmit and receive data under the control of the processor; A processor, configured to read the computer program in the memory and execute the method for measuring optical fiber temperature and / or strain according to any one of claims 1 to 3.

8. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and the computer program is used to enable a computer to execute the method for measuring optical fiber temperature and / or strain according to any one of claims 1 to 3.

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