Temperature measurement method and device based on optical fiber distributed sensing and storage medium

Abstract

The application provides a signal recovery method and device based on optical fiber distributed sensing and a storage medium, and belongs to the technical field of optical fiber sensing. The method comprises the following steps: determining the energy of a processed encoded anti-Stokes signal based on the energy of a spontaneous Stokes signal and the energy of a spontaneous anti-Stokes signal; and determining a temperature value based on the energy of the processed encoded anti-Stokes signal. The application solves the problem of stimulated Raman distortion caused by a long code bit number by demodulating a stimulated Raman scattering signal and constructing an algorithm containing only the processed encoded anti-Stokes signal, thereby improving the signal-to-noise ratio of the Raman scattering signal, reducing the error of the measured temperature, and making the measured temperature value more accurate.

Description

Technical Field

[0001] This invention relates to the field of fiber optic sensing technology, and in particular to a temperature measurement method, device, and storage medium based on fiber optic distributed sensing. Background Technology

[0002] Distributed fiber optic sensors use optical fiber as the transmission medium and offer advantages such as small size, light weight, flexibility, low loss, resistance to electromagnetic interference, and good radiation resistance. Their applications are wide-ranging, including oil and gas pipelines, fire alarm systems, reservoir and power cable monitoring, etc. Fiber optic distributed sensing technology primarily utilizes Rayleigh scattering, Brillouin scattering, or Raman scattering of pulses in optical fibers to carry spatially distributed information, thereby achieving distributed sensing. Among these, Raman scattering-based distributed sensors, with their ability to measure temperature and insensitivity to stress, have consistently been a research hotspot in the field of fiber optic sensing.

[0003] In existing technologies, the four key performance indicators of Raman distributed fiber optic sensing technology are sensing distance, spatial resolution, temperature resolution, and measurement time. Their performance all depends on the signal-to-noise ratio (SNR) of the measured Raman signal. SNR is primarily related to the pulse width and power. In a single-pulse Raman optical time-domain reflectometry (ROTDR) system, given a spatial resolution, the pulse power cannot be increased indefinitely due to nonlinear effects. Optical pulse coding technology can be used to improve the system's SNR. The core idea of ​​optical pulse coding technology is to use a specific, intensity-modulated sequence of light pulses of length L, composed of "1" and "0" symbols, to replace the single pump pulse in the sensing scheme. The detected response curve is then decoded using the corresponding decoding method, thereby improving the system's SNR without changing the measurement time.

[0004] In existing technologies, the longer the codeword, the higher the SNR of the system. However, when the code length increases, the spontaneous Raman scattering (SpRS) generated by a certain codeword will be stimulated and amplified by more other codewords entering the fiber later. This results in the measured signal containing both SpRS and stimulated Raman scattering (SRS) signals. Since the ROTDR system uses the linear relationship between temperature and the anti-Stokes (AS) signal in SpRS to demodulate the temperature, the SRS signal is superimposed on the measured signal, making the signals generated by each pulse non-independent. This violates the linear time-invariant condition of the code, causing distortion in the decoded response and affecting the accuracy of the measured temperature, resulting in errors in the demodulated temperature. Summary of the Invention

[0005] This invention provides a temperature measurement method, device, and storage medium based on fiber optic distributed sensing to solve the problem of large temperature measurement errors in the prior art.

[0006] This invention provides a temperature measurement method based on fiber optic distributed sensing, comprising:

[0007] The energy of the processed encoded anti-Stokes signal is determined based on the energy of the spontaneous Stokes signal and the energy of the spontaneous anti-Stokes signal.

[0008] The temperature value is determined based on the energy of the processed coded anti-Stokes signal.

[0009] Optionally, the energy of the processed encoded anti-Stokes signal is determined based on the energy of the spontaneous Stokes signal and the energy of the spontaneous anti-Stokes signal, including:

[0010] The energy of the encoded anti-Stokes signal is determined based on the energy of the spontaneous anti-Stokes signal, and the first stimulated Raman gain is determined based on the energy of the spontaneous Stokes signal; the first stimulated Raman gain is the stimulated Raman gain of the anti-Stokes scattered light as it varies along the optical fiber.

[0011] The energy of the encoded anti-Stokes signal is determined based on the energy of the encoded anti-Stokes signal and the energy of the encoded anti-Stokes signal after processing by the first stimulated Raman gain.

[0012] Optionally, the energy of the encoded anti-Stokes signal is determined based on the energy of the spontaneous anti-Stokes signal, including:

[0013] Determine the fiber length;

[0014] The third stimulated Raman gain is determined based on the fiber length; the third stimulated Raman gain is a Raman gain related to the fiber length.

[0015] The energy of the encoded anti-Stokes signal is determined based on the energy of the spontaneous anti-Stokes signal, the third stimulated Raman gain, and the number of 1s in the encoded sequence.

[0016] Optionally, the first stimulated Raman gain is determined based on the energy of the spontaneous Stokes signal, including:

[0017] The second stimulated Raman gain is determined based on the energy of the spontaneous Stokes signal; the second stimulated Raman gain is the stimulated Raman gain of the Stokes scattered light as it varies along the optical fiber.

[0018] The first stimulated Raman gain is determined based on the second stimulated Raman gain.

[0019] Optionally, the second stimulated Raman gain is determined based on the energy of the spontaneous Stokes signal, including:

[0020] The energy of the encoded Stokes signal is determined based on the energy of the spontaneous Stokes signal, and the energy of the reference Stokes signal is determined based on the energy of the spontaneous Stokes signal.

[0021] The second stimulated Raman gain is determined based on the energy of the coded Stokes signal and the energy of the reference Stokes signal.

[0022] Optionally, the energy of the encoded Stokes signal is determined based on the energy of the spontaneous Stokes signal, including:

[0023] Determine the fiber length;

[0024] The third stimulated Raman gain is determined based on the fiber length; the third stimulated Raman gain is a Raman gain related to the fiber length.

[0025] The energy of the encoded Stokes signal is determined based on the energy of the spontaneous Stokes signal, the third stimulated Raman gain, and the number of 1s in the encoded sequence.

[0026] Optionally, determining the energy of the reference Stokes signal based on the energy of the spontaneous Stokes signal includes:

[0027] Determining the energy of a single-pulse Stokes signal based on the energy of a spontaneous Stokes signal;

[0028] The energy of the reference Stokes signal is determined by convolving the energy of the single-pulse Stokes signal with the coded sequence.

[0029] Optionally, the energy of the single-pulse Stokes signal is determined based on the energy of the spontaneous Stokes signal, including:

[0030] Determine the fiber length;

[0031] The third stimulated Raman gain is determined based on the fiber length; the third stimulated Raman gain is a Raman gain related to the fiber length.

[0032] The energy of a single-pulse Stokes signal is determined based on the energy of the spontaneous Stokes signal and the third stimulated Raman gain.

[0033] The present invention also provides a temperature measurement device based on fiber optic distributed sensing, comprising:

[0034] The first determining module is used to determine the energy of the processed encoded anti-Stokes signal based on the energy of the spontaneous Stokes signal and the energy of the spontaneous anti-Stokes signal;

[0035] The second determining module is used to determine the temperature value based on the energy of the processed and encoded anti-Stokes signal.

[0036] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the temperature measurement method based on fiber optic distributed sensing as described above.

[0037] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the temperature measurement method based on fiber optic distributed sensing as described above.

[0038] The present invention also provides a computer program product, including a computer program that, when executed by a processor, implements any of the above-described temperature measurement methods based on fiber optic distributed sensing.

[0039] The temperature measurement method, device, and storage medium based on fiber optic distributed sensing provided by this invention constructs an algorithm that contains only the processed encoded anti-Stokes signal by descrambling the stimulated Raman scattering signal. This reduces the stimulated Raman distortion problem caused by long encoding bits, improves the signal-to-noise ratio of the Raman scattering signal, and reduces the error in temperature measurement, thereby making the measured temperature value more accurate. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0041] Figure 1This is a schematic flowchart of the temperature measurement method based on fiber optic distributed sensing provided by the present invention.

[0042] Figure 2 This is a diagram illustrating the steps of descrambling the encoded ROTDR stimulated signal provided by the present invention.

[0043] Figure 3 This is a comparison chart of the direct decoding of the time-domain signal of the 768-bit encoded AS scattered light provided by this invention, the decoding after algorithm compensation, and the single pulse.

[0044] Figure 4 This is a comparison chart of direct temperature demodulation and temperature demodulation after algorithm compensation using the 768-bit encoding provided by this invention.

[0045] Figure 5 This is a schematic diagram of the temperature measurement device based on fiber optic distributed sensing provided by the present invention.

[0046] Figure 6 This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0047] Currently, the most widely used technique based on the principle of spontaneous Raman scattering (SpRS) is Raman optical time-domain reflectometry. The principle of this technique is that the incident light interacts with the molecules moving in the optical fiber to produce Stokes (S) scattered light with a lower frequency and anti-Stokes (AS) scattered light with a higher frequency. The S-scattered light or Rayleigh scattered light and AS scattered light are then filtered out by a wavelength division multiplexing system.

[0048] Optical pulse coding techniques typically include Simplex coding, complementary Gray coding, cyclic codes, and genetic optimization algorithm coding. Generally, the longer the codeword, the greater the improvement in SNR, i.e., the improvement in SNR is...

[0049] The temperature measurement method, device, and storage medium based on fiber optic distributed sensing provided by this invention constructs an algorithm that contains only the processed encoded anti-Stokes signal by descrambling the stimulated Raman scattering signal. This reduces the stimulated Raman distortion problem caused by long encoding bits, improves the signal-to-noise ratio of the Raman scattering signal, and reduces the error in temperature measurement, thereby making the measured temperature value more accurate.

[0050] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0051] Figure 1 This is a flowchart illustrating the temperature measurement method based on fiber optic distributed sensing provided by the present invention, as shown below. Figure 1 As shown, the temperature measurement method based on fiber optic distributed sensing provided by the present invention may include:

[0052] Step 101: Determine the energy of the processed encoded anti-Stokes signal based on the energy of the spontaneous Stokes signal and the energy of the spontaneous anti-Stokes signal.

[0053] Specifically, this invention employs a classic Raman optical time-domain reflectometry (RTD) system structure. The laser emits continuous light, and the pulse source generates an electrical pulse signal to drive a semiconductor optical amplifier, which demodulates the continuous light into an optical pulse signal. The pump pulse then amplifies the power through an erbium-doped fiber amplifier. Because Raman scattering occurs during propagation in the fiber, Stokes light and anti-Stokes light are generated. Using a wavelength division multiplexing (WDM) system, the pump pulse enters the sensing fiber through the WDM system port. The Avalanche photodetector at the WDM system port converts the AS-scattered light and S-scattered light into electrical signals, which are then collected by a data acquisition card and stored in the central processing unit (CPU).

[0054] In some embodiments, a classic Raman optical time-domain reflectometry (OTDR) system structure is adopted. A wide-linewidth fiber laser outputs continuous light with a wavelength of 1550 nm. A pulse source generates a 768-bit electrical pulse signal with a pulse width of 20 ns to drive a semiconductor optical amplifier, which modulates the continuous light into a 768-bit, 20 ns optical pulse signal. The pump pulse is then amplified to a power of 1 W by an erbium-doped fiber amplifier. The pump pulse enters an 8 km sensing fiber through the 1550 nm port of the wavelength division multiplexing system. Then, the backscattered AS light and S-scattered light are converted into electrical signals by avalanche photodetectors at the 1450 nm and 1650 nm ports and collected by a data acquisition card.

[0055] Figure 2 This is a diagram illustrating the steps of descrambling the encoded ROTDR stimulated signal provided by the present invention, as shown below. Figure 2 As shown, the descrambling algorithm for stimulated Raman scattering signals is derived from... Figure 2As shown, this invention first uses a classic Raman optical time-domain reflectometry (RTD) system structure. A single pump pulse is first transmitted into the optical fiber. To improve the signal-to-noise ratio (SNR), the energy of the single-pulse Stokes scattering signal is measured multiple times at the receiving end, and the average value is taken to reduce noise interference. Then, the single-pulse ROTDR system is switched to an coded ROTDR system. The measured energy of the single-pulse Stokes scattering signal is convolved with the coded sequence of the input fiber to obtain the energy of the reference Stokes scattering signal. Then, according to a given number of acquisitions, the energy of the coded Stokes scattering signal is acquired multiple times, and the average value is taken. The stimulated Raman gain of the Stokes scattering light along the fiber is calculated based on the energy of the coded Stokes scattering signal and the energy of the reference Stokes scattering signal. Finally, the energy of the coded anti-Stokes signal after processing is calculated based on the stimulated Raman gain of the Stokes scattering light along the fiber and the energy of the coded anti-Stokes scattering signal. The energy of the coded anti-Stokes scattering signal is also obtained through multiple acquisitions according to a given number of acquisitions.

[0056] Step 102: Determine the temperature value based on the energy of the processed and encoded anti-Stokes signal.

[0057] Specifically, spontaneous anti-Stokes signals exhibit a linear relationship with changes in ambient temperature, thus sensing temperature. Since spontaneous Stokes signals are insensitive to temperature, they can be used as reference light to eliminate the effects of fiber optic bending. Therefore, temperature can be measured based on spontaneous anti-Stokes signals, using anti-Stokes scattered light as the signal channel and Stokes scattered light as the reference channel. The energy of the processed and encoded anti-Stokes signal is decoded to demodulate the temperature.

[0058] Figure 3 This is a comparison image of the direct decoding of the time-domain signal of 768-bit encoded AS scattered light provided by this invention, the decoding after algorithm compensation, and a single pulse. Figure 3 As shown, the relationship between the fiber transmission distance and voltage of the decoded anti-Stokes scattered light after algorithm compensation is closer to a linear change, where the voltage on the vertical axis refers to the voltage output by the avalanche photodetector when it converts the optical signal into an electrical signal.

[0059] Figure 4 This is a comparison chart of direct temperature demodulation and temperature demodulation after algorithm compensation using the 768-bit encoding provided by this invention, as shown in the image. Figure 4 As shown, direct temperature demodulation is affected by stimulated Raman scattering, which interferes with temperature measurement and leads to inaccurate results with large errors. However, by using an algorithm to compensate before temperature demodulation, the interference caused by stimulated Raman scattering can be eliminated, resulting in a more accurate temperature measurement. It can be seen that the measured temperature is around 25 degrees Celsius.

[0060] The temperature measurement method based on fiber optic distributed sensing provided by this invention constructs an algorithm that contains only the processed and encoded anti-Stokes signal by descrambling the stimulated Raman scattering signal. This reduces the stimulated Raman distortion problem caused by long encoding bits, improves the signal-to-noise ratio of the Raman scattering signal, and reduces the error in temperature measurement, thereby making the measured temperature value more accurate.

[0061] Optionally, the energy of the processed encoded anti-Stokes signal is determined based on the energy of the spontaneous Stokes signal and the energy of the spontaneous anti-Stokes signal, including:

[0062] The energy of the encoded anti-Stokes signal is determined based on the energy of the spontaneous anti-Stokes signal, and the first stimulated Raman gain is determined based on the energy of the spontaneous Stokes signal; the first stimulated Raman gain is the stimulated Raman gain of the anti-Stokes scattered light as it varies along the optical fiber.

[0063] The energy of the encoded anti-Stokes signal is determined based on the energy of the encoded anti-Stokes signal and the energy of the encoded anti-Stokes signal after processing by the first stimulated Raman gain.

[0064] Specifically, the energy of the processed encoded anti-Stokes signal containing only the anti-Stokes signal can be obtained from the energy of the encoded anti-Stokes signal and the first stimulated Raman gain, and this energy is used for decoding. The energy of the encoded anti-Stokes signal can be obtained from the energy of the spontaneous anti-Stokes signal, and the first stimulated Raman gain can be obtained from the energy of the spontaneous Stokes signal.

[0065] The first stimulated Raman gain refers to the stimulated Raman gain of the anti-Stokes scattered light as it changes along the fiber, and is related to the fiber length and the number of 1 symbols in the encoding.

[0066] In some embodiments, the energy of the processed and encoded anti-Stokes scattering signal is expressed as follows:

[0067]

[0068] in, The energy of the processed encoded anti-Stokes scattering signal is represented by z, where z represents the fiber length, T represents the temperature, and n represents the number of 1s in the encoding. This represents the energy of the encoded anti-Stokes scattering signal. This represents the stimulated Raman gain as the anti-Stokes scattered light changes along the optical fiber.

[0069] The temperature measurement method based on fiber optic distributed sensing provided by this invention constructs an algorithm that contains only the processed and encoded anti-Stokes signal by descrambling the stimulated Raman scattering signal. This reduces the stimulated Raman distortion problem caused by long encoding bits, improves the signal-to-noise ratio of the Raman scattering signal, and reduces the error in temperature measurement, thereby making the measured temperature value more accurate.

[0070] Optionally, the energy of the encoded anti-Stokes signal is determined based on the energy of the spontaneous anti-Stokes signal, including:

[0071] Determine the fiber length;

[0072] The third stimulated Raman gain is determined based on the fiber length; the third stimulated Raman gain is a Raman gain related to the fiber length.

[0073] The energy of the encoded anti-Stokes signal is determined based on the energy of the spontaneous anti-Stokes signal, the third stimulated Raman gain, and the number of 1s in the encoded sequence.

[0074] Specifically, the energy of the encoded anti-Stokes can be obtained from the energy of the spontaneous anti-Stokes, the third stimulated Raman gain, and the number of 1s in the encoded sequence. The third stimulated Raman gain can be obtained from the fiber length.

[0075] The third stimulated Raman gain refers to the Raman gain that is related to the fiber length.

[0076] In some embodiments, the energy of the encoded anti-Stokes spread signal is expressed as follows:

[0077]

[0078]

[0079] in, Let represent the energy of the encoded anti-Stokes scattering signal, z represent the fiber length, T represent the temperature, and n represent the number of 1s in the code. Let represent the energy of the spontaneous anti-Stokes scattering signal, K represent an empirical value and are a dimensionless constant, and g(z) represent the Raman gain related to the fiber length.

[0080] The temperature measurement method based on fiber optic distributed sensing provided by this invention constructs an algorithm that contains only the processed and encoded anti-Stokes signal by descrambling the stimulated Raman scattering signal. This reduces the stimulated Raman distortion problem caused by long encoding bits, improves the signal-to-noise ratio of the Raman scattering signal, and reduces the error in temperature measurement, thereby making the measured temperature value more accurate.

[0081] Optionally, the first stimulated Raman gain is determined based on the energy of the spontaneous Stokes signal, including:

[0082] The second stimulated Raman gain is determined based on the energy of the spontaneous Stokes signal; the second stimulated Raman gain is the stimulated Raman gain of the Stokes scattered light as it varies along the optical fiber.

[0083] The first stimulated Raman gain is determined based on the second stimulated Raman gain.

[0084] Specifically, the first stimulated Raman gain can be obtained from the second stimulated Raman gain, wherein the second stimulated Raman gain can be obtained from the energy of the spontaneous Stokes signal.

[0085] The second stimulated Raman gain refers to the stimulated Raman gain of the Stokes scattered light as it changes along the optical fiber, and is related to the fiber length and the number of 1 symbols in the encoding.

[0086] In some embodiments, the expression for the first stimulated Raman gain is as follows:

[0087]

[0088]

[0089] in, Let represent the stimulated Raman gain as the anti-Stokes scattered light varies along the fiber, z represent the fiber length, n represent the number of 1s in the encoding, K represent an empirical value and is a dimensionless constant, and g(z) represent the Raman gain related to the fiber length. This represents the stimulated Raman gain that varies along the fiber with the Stokes scattered light.

[0090] The temperature measurement method based on fiber optic distributed sensing provided by this invention constructs an algorithm that contains only the processed and encoded anti-Stokes signal by descrambling the stimulated Raman scattering signal. This reduces the stimulated Raman distortion problem caused by long encoding bits, improves the signal-to-noise ratio of the Raman scattering signal, and reduces the error in temperature measurement, thereby making the measured temperature value more accurate.

[0091] Optionally, the second stimulated Raman gain is determined based on the energy of the spontaneous Stokes signal, including:

[0092] The energy of the encoded Stokes signal is determined based on the energy of the spontaneous Stokes signal, and the energy of the reference Stokes signal is determined based on the energy of the spontaneous Stokes signal.

[0093] The second stimulated Raman gain is determined based on the energy of the coded Stokes signal and the energy of the reference Stokes signal.

[0094] Specifically, the second stimulated Raman gain can be obtained from the energy of the encoded Stokes signal and the energy of the reference Stokes signal, wherein the energy of the encoded Stokes signal and the energy of the reference Stokes signal can both be obtained from the energy of the spontaneous Stokes signal.

[0095] In some embodiments, the expression for the second stimulated Raman gain is as follows:

[0096]

[0097]

[0098] in, The stimulated Raman gain represents the variation of Stokes scattered light along the fiber, where z represents the fiber length, T represents the temperature, and n represents the number of 1s in the encoding. This represents the energy of the encoded Stokes signal. Let g(z) represent the energy of the reference Stokes signal, and g(z) represent the Raman gain related to the fiber length.

[0099] The temperature measurement method based on fiber optic distributed sensing provided by this invention constructs an algorithm that contains only the processed and encoded anti-Stokes signal by descrambling the stimulated Raman scattering signal. This reduces the stimulated Raman distortion problem caused by long encoding bits, improves the signal-to-noise ratio of the Raman scattering signal, and reduces the error in temperature measurement, thereby making the measured temperature value more accurate.

[0100] Optionally, the energy of the encoded Stokes signal is determined based on the energy of the spontaneous Stokes signal, including:

[0101] Determine the fiber length;

[0102] The third stimulated Raman gain is determined based on the fiber length; the third stimulated Raman gain is a Raman gain related to the fiber length.

[0103] The energy of the encoded Stokes signal is determined based on the energy of the spontaneous Stokes signal, the third stimulated Raman gain, and the number of 1s in the encoded sequence.

[0104] Specifically, the energy of the encoded Stokes signal can be obtained from the energy of the spontaneous Stokes signal, the third stimulated Raman gain, and the number of 1s in the encoded sequence. The third stimulated Raman gain can be obtained from the fiber length.

[0105] In some embodiments, the energy of the encoded Stokes signal is expressed as follows:

[0106]

[0107]

[0108] in, The energy of the encoded Stokes signal is represented by z, the fiber length is represented by T, the temperature is represented by n, and the number of 1s in the code is represented by n. denoted by , g(z) represents the energy of the spontaneous Stokes signal, and g(z) represents the Raman gain related to the fiber length.

[0109] The temperature measurement method based on fiber optic distributed sensing provided by this invention constructs an algorithm that contains only the processed and encoded anti-Stokes signal by descrambling the stimulated Raman scattering signal. This reduces the stimulated Raman distortion problem caused by long encoding bits, improves the signal-to-noise ratio of the Raman scattering signal, and reduces the error in temperature measurement, thereby making the measured temperature value more accurate.

[0110] Optionally, determining the energy of the reference Stokes signal based on the energy of the spontaneous Stokes signal includes:

[0111] Determining the energy of a single-pulse Stokes signal based on the energy of a spontaneous Stokes signal;

[0112] The energy of the reference Stokes signal is determined by convolving the energy of the single-pulse Stokes signal with the coded sequence.

[0113] Specifically, the energy of the reference Stokes signal can be obtained by convolving the energy of the single-pulse Stokes signal with the coded sequence. The energy of the single-pulse Stokes signal can be obtained from the energy of the spontaneous Stokes signal.

[0114] In some embodiments, the energy of the reference Stokes signal is expressed as follows:

[0115]

[0116] in, Let z represent the energy of the reference Stokes signal, z represent the fiber length, T represent the temperature, and n represent the number of 1s in the code. The energy of the single-pulse Stokes signal is represented by code(n), and the encoded sequence is represented by code(n).

[0117] The temperature measurement method based on fiber optic distributed sensing provided by this invention constructs an algorithm that contains only the processed and encoded anti-Stokes signal by descrambling the stimulated Raman scattering signal. This reduces the stimulated Raman distortion problem caused by long encoding bits, improves the signal-to-noise ratio of the Raman scattering signal, and reduces the error in temperature measurement, thereby making the measured temperature value more accurate.

[0118] Optionally, the energy of the single-pulse Stokes signal is determined based on the energy of the spontaneous Stokes signal, including:

[0119] Determine the fiber length;

[0120] The third stimulated Raman gain is determined based on the fiber length; the third stimulated Raman gain is a Raman gain related to the fiber length.

[0121] The energy of a single-pulse Stokes signal is determined based on the energy of the spontaneous Stokes signal and the third stimulated Raman gain.

[0122] Specifically, the energy of a single-pulse Stokes signal can be determined based on the energy of the spontaneous Stokes signal and the third stimulated Raman gain, where the third stimulated Raman gain can be obtained from the fiber length.

[0123] The energy of a single-pulse Stokes signal is expressed as follows:

[0124]

[0125]

[0126] in, The energy of the single-pulse Stokes signal is represented by z, the fiber length is represented by z, and the temperature is represented by T. Let represent the energy of the spontaneous Stokes signal, exp represent the exponential function with the natural constant e as the base, and g(z) represent the Raman gain related to the fiber length.

[0127] Since the gain of the stimulated Raman scattering signal of a single pulse is very low, g(z) can be considered as a small signal.

[0128] The temperature measurement method based on fiber optic distributed sensing provided by this invention constructs an algorithm that contains only the processed and encoded anti-Stokes signal by descrambling the stimulated Raman scattering signal. This reduces the stimulated Raman distortion problem caused by long encoding bits, improves the signal-to-noise ratio of the Raman scattering signal, and reduces the error in temperature measurement, thereby making the measured temperature value more accurate.

[0129] Figure 5 This is a schematic diagram of the temperature measurement device based on fiber optic distributed sensing provided by the present invention, as shown below. Figure 5 As shown, the device includes:

[0130] The first determining module 510 is used to determine the energy of the processed encoded anti-Stokes signal based on the energy of the spontaneous Stokes signal and the energy of the spontaneous anti-Stokes signal.

[0131] The second determining module 520 is used to determine the temperature value based on the energy of the processed encoded anti-Stokes signal.

[0132] Optionally, the first determining module includes an energy determining module for the encoded anti-Stokes signal and a first stimulated Raman gain determining module, as well as an energy determining module for the processed encoded anti-Stokes signal.

[0133] The module for determining the energy of the encoded anti-Stokes signal and the first stimulated Raman gain is used to determine the energy of the encoded anti-Stokes signal based on the energy of the spontaneous anti-Stokes signal, and to determine the first stimulated Raman gain based on the energy of the spontaneous Stokes signal; the first stimulated Raman gain is the stimulated Raman gain of the anti-Stokes scattered light as it changes along the optical fiber.

[0134] The energy determination module of the processed encoded anti-Stokes signal is used to determine the energy of the processed encoded anti-Stokes signal based on the energy of the encoded anti-Stokes signal and the first stimulated Raman gain.

[0135] Optionally, the energy determination module for the encoded anti-Stokes signal and the first stimulated Raman gain includes an optical fiber length determination module, a third stimulated Raman gain determination module, and an energy determination module for the encoded anti-Stokes signal.

[0136] The fiber length determination module is used to determine the fiber length;

[0137] The third stimulated Raman gain determination module is used to determine the third stimulated Raman gain based on the fiber length; the third stimulated Raman gain is a Raman gain related to the fiber length.

[0138] The energy determination module for the encoded anti-Stokes signal is used to determine the energy of the encoded anti-Stokes signal based on the energy of the spontaneous anti-Stokes signal, the third stimulated Raman gain, and the number of 1s in the encoded sequence.

[0139] Optionally, the energy of the encoded anti-Stokes signal and the first stimulated Raman gain determination module include a second stimulated Raman gain determination module and a first stimulated Raman gain determination module;

[0140] The second stimulated Raman gain first determination module is used to determine the second stimulated Raman gain based on the energy of the spontaneous Stokes signal; the second stimulated Raman gain is the stimulated Raman gain of the Stokes scattered light as it changes along the optical fiber;

[0141] The first stimulated Raman gain determination module is used to determine the first stimulated Raman gain based on the second stimulated Raman gain.

[0142] Optionally, the second stimulated Raman gain determination module includes a module for determining the energy of the encoded Stokes signal and the energy of the reference Stokes signal, as well as a second stimulated Raman gain determination module.

[0143] The module for determining the energy of the encoded Stokes signal and the energy of the reference Stokes signal is used to determine the energy of the encoded Stokes signal based on the energy of the spontaneous Stokes signal, and to determine the energy of the reference Stokes signal based on the energy of the spontaneous Stokes signal.

[0144] The second stimulated Raman gain second determination module is used to determine the second stimulated Raman gain based on the energy of the encoded Stokes signal and the energy of the reference Stokes signal.

[0145] Optionally, the module for determining the energy of the encoded Stokes signal and the energy of the reference Stokes signal includes the fiber length determination module, the third stimulated Raman gain determination module, and the module for determining the energy of the encoded Stokes signal.

[0146] The fiber length determination module is used to determine the fiber length;

[0147] The third stimulated Raman gain determination module is used to determine the third stimulated Raman gain based on the fiber length; the third stimulated Raman gain is a Raman gain related to the fiber length.

[0148] The energy determination module for the encoded Stokes signal is used to determine the energy of the encoded Stokes signal based on the energy of the spontaneous Stokes signal, the third stimulated Raman gain, and the number of 1s in the encoded sequence.

[0149] Optionally, the module for determining the energy of the encoded Stokes signal and the energy of the reference Stokes signal includes a first module for determining the energy of the single-pulse Stokes signal and a module for determining the energy of the reference Stokes signal;

[0150] The first energy determination module of the single-pulse Stokes signal is used to determine the energy of the single-pulse Stokes signal based on the energy of the spontaneous Stokes signal.

[0151] The reference Stokes signal energy determination module is used to convolve the energy of the single-pulse Stokes signal with the coded sequence to determine the energy of the reference Stokes signal.

[0152] Optionally, the first energy determination module of the single-pulse Stokes signal includes the fiber length determination module, the third stimulated Raman gain determination module, and the second energy determination module of the single-pulse Stokes signal;

[0153] The fiber length determination module is used to determine the fiber length;

[0154] The third stimulated Raman gain determination module is used to determine the third stimulated Raman gain based on the fiber length; the third stimulated Raman gain is a Raman gain related to the fiber length.

[0155] The second energy determination module of the single-pulse Stokes signal is used to determine the energy of the single-pulse Stokes signal based on the energy of the spontaneous Stokes signal and the third stimulated Raman gain.

[0156] Specifically, the temperature measurement device based on fiber optic distributed sensing provided in this application embodiment can realize all the method steps implemented in the above-mentioned temperature measurement method embodiment based on fiber optic distributed sensing, and can achieve the same technical effect. Here, the parts that are the same as those in the method embodiment and the beneficial effects will not be described in detail.

[0157] Figure 6 This is a schematic diagram of the structure of the electronic device provided by the present invention, such as... Figure 6 As shown, the electronic device may include: a processor 610, a communication interface 620, a memory 630, and a communication bus 640, wherein the processor 610, the communication interface 620, and the memory 630 communicate with each other through the communication bus 640. The processor 610 can call logical instructions in the memory 630 to execute a temperature measurement method based on fiber optic distributed sensing, the method including:

[0158] The energy of the processed encoded anti-Stokes signal is determined based on the energy of the spontaneous Stokes signal and the energy of the spontaneous anti-Stokes signal.

[0159] The temperature value is determined based on the energy of the processed, encoded anti-Stokes signal.

[0160] Furthermore, the logical instructions in the aforementioned memory 630 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, essentially, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0161] On the other hand, the present invention also provides a computer program product, the computer program product comprising a computer program that can be stored on a non-transitory computer-readable storage medium, wherein when the computer program is executed by a processor, the computer is able to execute the temperature measurement method based on fiber optic distributed sensing provided by the above methods, the method comprising:

[0162] The energy of the processed encoded anti-Stokes signal is determined based on the energy of the spontaneous Stokes signal and the energy of the spontaneous anti-Stokes signal.

[0163] The temperature value is determined based on the energy of the processed, encoded anti-Stokes signal.

[0164] In another aspect, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to perform the temperature measurement method based on fiber optic distributed sensing provided by the methods described above, the method comprising:

[0165] The energy of the processed encoded anti-Stokes signal is determined based on the energy of the spontaneous Stokes signal and the energy of the spontaneous anti-Stokes signal.

[0166] The temperature value is determined based on the energy of the processed, encoded anti-Stokes signal.

[0167] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0168] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0169] It should also be noted that the terms "first," "second," etc., used in the embodiments of this application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first" and "second" are generally of the same class, and the number of objects is not limited. For example, the first object can be one or more.

[0170] In this application's embodiments, "determine B based on A" means that factor A must be considered when determining B. It is not limited to "B can be determined based solely on A," but should also include: "determine B based on A and C," "determine B based on A, C, and E," "determine C based on A, and further determine B based on C," etc. Additionally, it can include using A as a condition for determining B, for example, "when A meets the first condition, determine B using the first method"; another example, "when A meets the second condition, determine B," etc.; another example, "when A meets the third condition, determine B based on the first parameter," etc. Of course, it can also be a condition where A is a factor in determining B, for example, "when A meets the first condition, determine C using the first method, and further determine B based on C," etc.

[0171] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A temperature measurement method based on fiber optic distributed sensing, characterized in that, include: The energy of the processed, encoded anti-Stokes signal is determined based on the energy of the spontaneous Stokes signal and the energy of the spontaneous anti-Stokes signal, including: The energy of the encoded anti-Stokes signal is determined based on the energy of the spontaneous anti-Stokes signal, and the first stimulated Raman gain is determined based on the energy of the spontaneous Stokes signal; the first stimulated Raman gain is the stimulated Raman gain of the anti-Stokes scattered light as it varies along the optical fiber. The energy of the encoded anti-Stokes signal is determined based on the energy of the encoded anti-Stokes signal and the first stimulated Raman gain. The temperature value is determined based on the energy of the processed coded anti-Stokes signal.

2. The temperature measurement method based on fiber optic distributed sensing according to claim 1, characterized in that, The energy of the encoded anti-Stokes signal is determined based on the energy of the spontaneous anti-Stokes signal, including: Determine the fiber length; The third stimulated Raman gain is determined based on the fiber length; the third stimulated Raman gain is a Raman gain related to the fiber length. The energy of the encoded anti-Stokes signal is determined based on the energy of the spontaneous anti-Stokes signal, the third stimulated Raman gain, and the number of 1s in the encoded sequence.

3. The temperature measurement method based on fiber optic distributed sensing according to claim 1, characterized in that, The first stimulated Raman gain is determined based on the energy of the spontaneous Stokes signal, including: The second stimulated Raman gain is determined based on the energy of the spontaneous Stokes signal; the second stimulated Raman gain is the stimulated Raman gain of the Stokes scattered light as it varies along the optical fiber. The first stimulated Raman gain is determined based on the second stimulated Raman gain.

4. The temperature measurement method based on fiber optic distributed sensing according to claim 3, characterized in that, Determining the second stimulated Raman gain based on the energy of the spontaneous Stokes signal includes: The energy of the encoded Stokes signal is determined based on the energy of the spontaneous Stokes signal, and the energy of the reference Stokes signal is determined based on the energy of the spontaneous Stokes signal. The second stimulated Raman gain is determined based on the energy of the coded Stokes signal and the energy of the reference Stokes signal.

5. The temperature measurement method based on fiber optic distributed sensing according to claim 4, characterized in that, The energy of the encoded Stokes signal is determined based on the energy of the spontaneous Stokes signal, including: Determine the fiber length; The third stimulated Raman gain is determined based on the fiber length; the third stimulated Raman gain is a Raman gain related to the fiber length. The energy of the encoded Stokes signal is determined based on the energy of the spontaneous Stokes signal, the third stimulated Raman gain, and the number of 1s in the encoded sequence.

6. The temperature measurement method based on fiber optic distributed sensing according to claim 4, characterized in that, Determining the energy of the reference Stokes signal based on the energy of the spontaneous Stokes signal includes: Determining the energy of a single-pulse Stokes signal based on the energy of a spontaneous Stokes signal; The energy of the reference Stokes signal is determined by convolving the energy of the single-pulse Stokes signal with the coded sequence.

7. The temperature measurement method based on fiber optic distributed sensing according to claim 6, characterized in that, Determining the energy of a single-pulse Stokes signal based on the energy of a spontaneous Stokes signal includes: Determine the fiber length; The third stimulated Raman gain is determined based on the fiber length; the third stimulated Raman gain is a Raman gain related to the fiber length. The energy of a single-pulse Stokes signal is determined based on the energy of the spontaneous Stokes signal and the third stimulated Raman gain.

8. A temperature measurement device based on fiber optic distributed sensing, characterized in that, include: The first determining module is used to determine the energy of the processed encoded anti-Stokes signal based on the energy of the spontaneous Stokes signal and the energy of the spontaneous anti-Stokes signal, including: The energy of the encoded anti-Stokes signal is determined based on the energy of the spontaneous anti-Stokes signal, and the first stimulated Raman gain is determined based on the energy of the spontaneous Stokes signal; the first stimulated Raman gain is the stimulated Raman gain of the anti-Stokes scattered light as it varies along the optical fiber. The energy of the encoded anti-Stokes signal is determined based on the energy of the encoded anti-Stokes signal and the first stimulated Raman gain. The second determining module is used to determine the temperature value based on the energy of the processed and encoded anti-Stokes signal.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the temperature measurement method based on fiber optic distributed sensing as described in any one of claims 1 to 7.

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