Optical fiber along-line temperature measurement method, device, equipment and medium

Abstract

This application discloses a method, apparatus, device, and medium for measuring temperature along an optical fiber. The method includes: acquiring the actual optical power of the anti-Stokes light in the optical fiber loop and the difference function of the actual optical fiber transmission loss coefficient of the anti-Stokes light at each scattering point in the optical fiber; for any scattering point in the optical fiber, determining the actual ambient temperature of the scattering point based on the difference function of the actual optical power of the anti-Stokes light in the optical fiber loop and the actual optical fiber transmission loss coefficient of the anti-Stokes light; and determining the actual ambient temperature of the optical fiber based on the actual ambient temperatures of each scattering point in the optical fiber. In this application, the actual optical power of the anti-Stokes light in the optical fiber loop at the scattering point is obtained by filtering the optical power of Rayleigh scattered light included in the optical power measurement data of the anti-Stokes light at the scattering point, thereby improving the signal-to-noise ratio of the anti-Stokes light signal and thus improving the accuracy of temperature measurement along the optical fiber.

Description

Technical Field

[0001] This application belongs to the field of fiber optic temperature measurement, specifically relating to a method, device, equipment, and medium for measuring temperature along a fiber optic cable. Background Technology

[0002] The core advantage of distributed fiber optic sensing (DTS) based on Raman scattering lies in its ability to transform an entire optical fiber into a continuous, distributed temperature sensor, enabling real-time monitoring of the temperature field over a spatial range of tens of kilometers with spatial resolution at the meter or even centimeter level. This technology utilizes the temperature sensitivity of backscattering generated by pulsed lasers in the optical fiber to demodulate temperature. It possesses outstanding advantages such as resistance to electromagnetic interference, intrinsic safety, corrosion resistance, and good long-term stability, playing an irreplaceable role in fields such as oil and gas pipeline leak monitoring, high-voltage cable overheating early warning, tunnel fire alarms, and structural health monitoring of large infrastructure.

[0003] In the specific implementation of temperature demodulation, single-path temperature demodulation technology is used. Single-path temperature demodulation technology utilizes the influence of the ambient temperature of the backscattered anti-Stokes optical signal on the optical fiber, and demodulates the temperature change along the optical fiber by measuring the backscattered anti-Stokes optical signal.

[0004] However, since the intensity of Rayleigh scattered light is usually 3 to 5 orders of magnitude higher than that of Raman scattered light, it is difficult to completely filter out Rayleigh scattered light in practice using only spectral filters. The residual Rayleigh scattering noise will seriously interfere with the anti-Stokes signal, resulting in significant errors in the temperature demodulation results, which in turn leads to the technical problem of inaccurate temperature measurement along the optical fiber. Summary of the Invention

[0005] The purpose of this application is to provide a method, apparatus, device, and medium for measuring temperature along optical fibers, which can solve the problem of inaccurate temperature measurement along optical fibers.

[0006] To solve the above-mentioned technical problems, this application is implemented as follows: In a first aspect, embodiments of this application provide a method for measuring temperature along an optical fiber, the method comprising: The difference function between the actual optical power of the anti-Stokes light in the fiber loop and the actual fiber transmission loss coefficient of the anti-Stokes light at each scattering point in the optical fiber is obtained. The actual optical power of the anti-Stokes light in the fiber loop at each scattering point is obtained by filtering out the Rayleigh scattered light power from the optical power measurement data of the anti-Stokes light at the scattering point. The actual optical power of the anti-Stokes light in the fiber loop at each scattering point includes the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under a first preset constant ambient temperature and the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under the actual ambient temperature to be measured. For any of the scattering points in the optical fiber, the actual ambient temperature of the scattering point is determined based on the difference function between the actual optical power of the anti-Stokes light in the optical fiber loop at the scattering point and the actual optical fiber transmission loss coefficient of the anti-Stokes light. The actual ambient temperature of the optical fiber is determined based on the actual ambient temperature of each scattering point in the optical fiber.

[0007] Optionally, the optical power measurement data of the anti-Stokes light at the scattering point includes the optical power measurement data of the front-end anti-Stokes light and the optical power measurement data of the rear-end anti-Stokes light at the scattering point; The actual optical power of the anti-Stokes light in the fiber loop at each scattering point in the fiber includes: For any scattering point in the optical fiber, acquire the optical power measurement data of the front-end anti-Stokes light, the optical power measurement data of the rear-end anti-Stokes light, and the optical power of the Rayleigh scattered light at the scattering point; The actual optical power of the anti-Stokes light at the front end of the scattering point is determined based on the optical power measurement data of the anti-Stokes light at the scattering point and the optical power of the Rayleigh scattered light. Based on the optical power measurement data of the back-end anti-Stokes light at the scattering point and the optical power of the Rayleigh scattered light, determine the actual optical power of the back-end anti-Stokes light at the scattering point; The actual optical power of the anti-Stokes light in the fiber optic loop at the scattering point is determined based on the actual optical power of the anti-Stokes light at the front end of the scattering point and the actual optical power of the anti-Stokes light at the rear end of the scattering point.

[0008] Optionally, the method for obtaining the actual fiber transmission loss coefficient difference function of the anti-Stokes light includes: For the midpoint of any two adjacent scattering points in the optical fiber, obtain the difference in the actual optical fiber transmission loss coefficient between the midpoints of the two adjacent scattering points. The actual fiber transmission loss coefficient difference function of the anti-Stokes light is determined based on the difference in the actual fiber transmission loss coefficient at the midpoint of the two adjacent scattering points.

[0009] Optionally, obtaining the actual fiber transmission loss coefficient difference between the midpoints of the two adjacent scattering points includes: The actual optical power of the anti-Stokes light at the front end of two adjacent scattering points is obtained at the ambient temperature to be measured, and the actual optical power of the anti-Stokes light at the front end of two adjacent scattering points is obtained at a first preset constant ambient temperature. The difference in the actual optical fiber transmission loss coefficient at the midpoint of the two adjacent scattering points is determined based on the actual optical power of the anti-Stokes light at the front end of the two adjacent scattering points under the measured ambient temperature and the actual optical power of the anti-Stokes light at the front end of the two adjacent scattering points under the first preset constant ambient temperature.

[0010] Optionally, determining the difference in the actual fiber transmission loss coefficient at the midpoint of the two adjacent scattering points based on the actual optical power of the anti-Stokes light at the front end of the two adjacent scattering points under the ambient temperature to be measured and the actual optical power of the anti-Stokes light at the front end of the two adjacent scattering points under a first preset constant ambient temperature includes:

[0011] in, The difference in the actual fiber transmission loss coefficient between the midpoints of the two adjacent scattering points. , These are two adjacent scattering points at the ambient temperature to be measured. , The actual optical power of the front-end anti-Stokes light, , The two adjacent scattering points are respectively under the first preset constant ambient temperature. , The actual optical power of the front-end anti-Stokes light.

[0012] Optionally, determining the actual ambient temperature of the scattering point based on the difference function between the actual optical power of the anti-Stokes light in the fiber loop at the scattering point and the actual fiber transmission loss coefficient of the anti-Stokes light includes:

[0013] in, The actual ambient temperature at the scattering point. The coefficients are related to the scattering cross section and wavelength / frequency of the anti-Stokes light. is Planck's constant. The frequency of the fiber molecules in the optical fiber is the vibration frequency. The first preset constant ambient temperature, The actual optical power of the anti-Stokes light in the fiber optic loop at the scattering point is given by the first preset constant ambient temperature. The actual optical power of the anti-Stokes light in the fiber optic loop at the scattering point is given at the actual ambient temperature to be measured. The difference function is the actual fiber transmission loss coefficient of the anti-Stokes light. The distance from the scattering point to the fiber optic tip is [distance]. This represents the maximum distance from the back end of the optical fiber to the front end.

[0014] Optionally, before the step of obtaining the difference function between the actual optical power of the anti-Stokes light in the fiber loop and the actual fiber transmission loss coefficient of the anti-Stokes light at each scattering point in the fiber, the method further includes: Obtain the optical power of the Rayleigh scattered light at the scattering point.

[0015] Optionally, the step of obtaining the optical power of the Rayleigh scattered light at the scattering point includes: Obtain a function related to a second preset constant ambient temperature, wherein the first preset constant ambient temperature is less than the second preset constant ambient temperature; The optical power of the Rayleigh scattered light at the scattering point is determined based on the function related to the second preset constant ambient temperature.

[0016] Optionally, the function for obtaining the second preset constant ambient temperature includes: The actual optical power of the anti-Stokes light in the fiber loop at the scattering point and the actual fiber transmission loss coefficient difference function of the first anti-Stokes light are obtained under the second preset constant ambient temperature. The actual fiber transmission loss coefficient difference function of the first anti-Stokes light is obtained based on the fiber transmission loss coefficient difference between the fiber transmission loss coefficient of the anti-Stokes light at the midpoint of the two adjacent scattering points under the first preset constant ambient temperature and the fiber transmission loss coefficient of the anti-Stokes light at the midpoint of the two adjacent scattering points under the second preset constant ambient temperature. Based on the second preset constant ambient temperature, the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under the first preset constant ambient temperature, the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under the second preset constant ambient temperature, and the difference function of the actual fiber transmission loss coefficient of the first anti-Stokes light, a function related to the second preset constant ambient temperature is determined.

[0017] Optionally, determining the function related to the second preset constant ambient temperature based on the second preset constant ambient temperature, the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under the first preset constant ambient temperature, the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under the second preset constant ambient temperature, and the difference function of the actual fiber transmission loss coefficient of the first anti-Stokes light includes:

[0018] in, The second preset constant ambient temperature, The coefficients are related to the scattering cross section and wavelength / frequency of the anti-Stokes light. is Planck's constant. The frequency of the fiber molecules in the optical fiber is the vibration frequency. The first preset constant ambient temperature, To determine the actual optical power of the anti-Stokes light in the fiber optic loop at the scattering point under a first preset constant ambient temperature, The actual optical power of the anti-Stokes light in the fiber optic loop at the scattering point is given by the second preset constant ambient temperature. The difference function is the actual optical fiber transmission loss coefficient of the first anti-Stokes light.

[0019] Optionally, determining the Rayleigh scattered light power at the scattering point based on the function related to the second preset constant ambient temperature includes: The function related to the second preset constant ambient temperature is transformed to obtain a first parameter and a second parameter. The first parameter is determined based on the optical power measurement data of the front anti-Stokes light of any two adjacent scattering points under the first preset constant ambient temperature, the optical power measurement data of the front anti-Stokes light of any two adjacent scattering points under the second preset constant ambient temperature, and the optical power of the Rayleigh scattered light of any two adjacent scattering points. The second parameter is determined based on the optical power measurement data of the front anti-Stokes light and the rear anti-Stokes light of the scattering point under the first preset constant ambient temperature, the optical power measurement data of the front anti-Stokes light and the rear anti-Stokes light of the scattering point under the second preset constant ambient temperature, and the optical power of the Rayleigh scattered light of the scattering point. Determine the error function based on the first parameter and the second parameter; The optical power of the Rayleigh scattered light at the scattering point is determined based on the error function.

[0020] Secondly, embodiments of this application provide an optical fiber along-line temperature measuring device, the optical fiber along-line temperature measuring device comprising: The data acquisition module is used to acquire the actual optical power of the anti-Stokes light in the fiber loop at each scattering point in the optical fiber and the difference function of the actual fiber transmission loss coefficient of the anti-Stokes light; wherein, the actual optical power of the anti-Stokes light in the fiber loop at the scattering point is obtained by filtering out the optical power of the Rayleigh scattered light at the scattering point from the optical power measurement data of the anti-Stokes light at the scattering point, and the actual optical power of the anti-Stokes light in the fiber loop at the scattering point includes the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under a first preset constant ambient temperature and the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under the actual ambient temperature to be measured; The module for determining the actual ambient temperature of a scattering point is used to determine the actual ambient temperature of any scattering point in the optical fiber based on the difference function between the actual optical power of the anti-Stokes light in the optical fiber loop and the actual optical fiber transmission loss coefficient of the anti-Stokes light. The module for acquiring the actual ambient temperature along the optical fiber is used to determine the actual ambient temperature of the optical fiber based on the actual ambient temperature of each scattering point in the optical fiber.

[0021] Thirdly, embodiments of this application provide an electronic device including a processor, a memory, and a program or instructions stored in the memory and executable on the processor, wherein the program or instructions, when executed by the processor, implement the steps of the method described in the first aspect.

[0022] Fourthly, embodiments of this application provide a readable storage medium on which a program or instructions are stored, which, when executed by a processor, implement the steps of the method described in the first aspect.

[0023] Fifthly, embodiments of this application provide a chip, the chip including a processor and a communication interface, the communication interface being coupled to the processor, the processor being used to run programs or instructions to implement the method as described in the first aspect.

[0024] In this embodiment, the actual optical power of the anti-Stokes light in the fiber loop and the difference function of the actual fiber transmission loss coefficient of the anti-Stokes light at each scattering point in the optical fiber are obtained. The actual optical power of the anti-Stokes light in the fiber loop at the scattering point is obtained by filtering out the Rayleigh scattered light power from the optical power measurement data of the anti-Stokes light at the scattering point. The actual optical power of the anti-Stokes light in the fiber loop at the scattering point includes the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under a first preset constant ambient temperature and the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under the actual ambient temperature to be measured. For any scattering point in the optical fiber, the actual ambient temperature of the scattering point is determined based on the difference function of the actual optical power of the anti-Stokes light in the fiber loop and the actual fiber transmission loss coefficient of the anti-Stokes light. The actual ambient temperature of the optical fiber is determined based on the actual ambient temperature of each scattering point in the optical fiber. In this application, the actual optical power of the anti-Stokes light in the fiber optic loop at the scattering point is obtained by filtering the Rayleigh scattering light power contained in the optical power measurement data of the anti-Stokes light at the scattering point. This improves the signal-to-noise ratio of the anti-Stokes light signal, thereby making the actual ambient temperature at the scattering point calculated based on the actual optical power of the anti-Stokes light in the fiber optic loop more accurate. Furthermore, this improves the accuracy of temperature measurement along the fiber optic line. In addition, this application achieves high-precision temperature measurement without relying on extremely high-performance, high-cost optical filters during fiber optic line temperature measurement, significantly reducing hardware complexity and manufacturing costs, and enhancing the reliability of temperature measurement. Attached Figure Description

[0025] Figure 1 This is a flowchart illustrating the steps of a method for measuring temperature along an optical fiber according to an embodiment of this application. Figure 2 This is a block diagram of an optical fiber temperature measurement device provided in an embodiment of this application; Figure 3 This is a structural diagram of an electronic device provided in an embodiment of this application. Detailed Implementation

[0026] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0027] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0028] The following description, in conjunction with the accompanying drawings, details a method, apparatus, device, and medium for measuring temperature along an optical fiber provided in this application, through specific embodiments and application scenarios.

[0029] Figure 1 This is a flowchart illustrating the steps of a method for measuring temperature along an optical fiber according to an embodiment of this application. Figure 1 As shown, the method includes: Step 101: Obtain the difference function between the actual optical power of the anti-Stokes light in the fiber loop and the actual fiber transmission loss coefficient of the anti-Stokes light at each scattering point in the fiber; wherein, the actual optical power of the anti-Stokes light in the fiber loop at the scattering point is obtained by filtering out the optical power of the Rayleigh scattered light from the optical power measurement data of the anti-Stokes light at the scattering point, and the actual optical power of the anti-Stokes light in the fiber loop at the scattering point includes the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under the first preset constant ambient temperature and the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under the actual ambient temperature to be measured.

[0030] Step 102: For any scattering point in the optical fiber, determine the actual ambient temperature of the scattering point based on the difference function between the actual optical power of the anti-Stokes light in the optical fiber loop and the actual optical fiber transmission loss coefficient of the anti-Stokes light.

[0031] Step 103: Determine the actual ambient temperature of the optical fiber based on the actual ambient temperature of each scattering point in the optical fiber.

[0032] In some embodiments of this application, in the dual-loop demodulation scheme, the optical fiber is configured as a loop. A pulsed laser emits a pulsed laser beam, which is incident into the optical fiber. When the laser pulse propagates in the optical fiber, it undergoes inelastic collisions with the fiber molecules, generating Raman scattered light. The Raman scattered light includes anti-Stokes light.

[0033] We can define one end of an optical fiber as the fiber front end and the other end as the fiber back end. The transmission direction of a pulsed laser can be controlled by an optical switch; that is, the optical switch can control whether the pulsed laser is incident from the fiber front end and transmitted to the fiber back end, or from the fiber back end and transmitted to the fiber front end.

[0034] The optical fiber can be divided into several scattering points according to its spatial resolution. For example, if the spatial resolution of the optical fiber is 1m, then there will be a scattering point every 1m. The number of scattering points is related to the spatial resolution and length of the optical fiber.

[0035] To obtain the actual ambient temperature of the scattering point, the actual optical power of the anti-Stokes light in the fiber loop and the difference function of the actual fiber transmission loss coefficient of the anti-Stokes light in each of the several scattering points in the fiber can be obtained in advance. The actual optical power of the anti-Stokes light in the fiber loop of the scattering point is obtained by filtering out the optical power of the Rayleigh scattered light from the optical power measurement data of the anti-Stokes light in the scattering point. The actual optical power of the anti-Stokes light in the fiber loop of the scattering point includes the actual optical power of the anti-Stokes light in the fiber loop of the scattering point at the first preset constant ambient temperature and the actual optical power of the anti-Stokes light in the fiber loop of the scattering point at the actual ambient temperature to be measured.

[0036] For any scattering point in an optical fiber, the actual ambient temperature of the scattering point is determined based on the difference function between the actual optical power of the anti-Stokes light in the optical fiber loop and the actual optical fiber transmission loss coefficient of the anti-Stokes light. Specifically, the calculation formula for the actual ambient temperature of the scattering point can be derived in advance, and the actual ambient temperature of the scattering point can be calculated based on the calculation formula.

[0037] The specific implementation process for deriving the formula for calculating the actual ambient temperature of the scattering point is as follows: Considering that the optical fiber transmission loss of anti-Stokes light varies with the temperature and distance along the optical fiber, the optical power of anti-Stokes light at the front end of the optical fiber can be expressed as formula (1), and the optical power of anti-Stokes light at the back end of the optical fiber can be expressed as formula (2).

[0038] Formula (1) Formula (2) Formula (3) in, This indicates the optical power of the anti-Stokes light at the fiber optic head end. The optical power of the anti-Stokes light at the back end of the optical fiber. The distance from the light emitting end to the scattering point. , This is the maximum distance from the back end of the optical fiber to the optical transmitter. This indicates the ambient temperature (Kelvin) of the optical fiber, starting from the fiber tip. This indicates the ambient temperature (Kelvin temperature) of the optical fiber starting from the back end of the optical fiber. Indicates distance from the fiber front end The ambient temperature where the optical fiber is located Indicates distance from the back end of the optical fiber The ambient temperature where the optical fiber is located Boltzmann constant, representing a coefficient related to the scattering cross section and wavelength / frequency of the anti-Stokes light. The fiber transmission loss coefficient of pulsed laser light is represented by... The fiber transmission loss coefficient representing the anti-Stokes light at the fiber front end. The fiber transmission loss coefficient represents the anti-Stokes light at the back end of the optical fiber, where, and Besides being related to the inherent material properties of the optical fiber (intrinsic loss), it is also related to the distance between the scattering point and the light emitter. and [0, The ambient temperature along the fiber optic path within the range of fiber optic scattering. and Regarding (temperature-related losses) It is only related to the material properties of the optical fiber itself. This coefficient represents the population of the molecular energy levels in the optical fiber and is related to the ambient temperature of the optical fiber. is Planck's constant. The frequency of the fiber molecules in the optical fiber is the vibrational frequency. and This is an integral dummy variable. Due to the fiber transmission loss coefficient of anti-Stokes light... and The distance between the scattering point and the light emitter varies with the ambient temperature along the fiber optic scattering path; therefore, the distance between the fiber's front and back ends and the light emitter varies. The fiber transmission loss coefficient of the anti-Stokes light at the scattering point is expressed by the functional as follows: The corresponding optical power is subscript represent (Fiber optic front end) or (Fiber optic back end).

[0039] Since formula (1) is the formula for calculating the optical power of the anti-Stokes light at the fiber front end based on the fiber front-end zero point (i.e., the optical transmitter), and formula (2) is the formula for calculating the optical power of the anti-Stokes light at the fiber back end based on the fiber back end, and since both are now based on the fiber front-end zero point, the distance from the fiber front end... The anti-Stokes power at the front end of the optical fiber is calculated according to formula (1), and the distance between this point and the back end of the optical fiber is... The formula for calculating the back-end anti-Stokes power at this point needs to be transformed from formula (2) to obtain formula (4).

[0040] Formula (4) in, For the back end of the optical fiber The back-end anti-Stokes power at the scattering point For the back end of the optical fiber The fiber transmission loss coefficient of the anti-Stokes light at the scattering point is given by formula (4), and the meanings of the other letters in formula (4) are as described above.

[0041] Because of [0, Any point within the range There is always , Then, by transforming formula (4), we get formula (5).

[0042] Formula (5) in, For the distance fiber front end The fiber transmission loss coefficient of the anti-Stokes light at the scattering point. For the integral dummy variable, the meanings of the other letters in formula (5) are as described above.

[0043] Substituting the optical power of the front-end anti-Stokes light and the optical power of the back-end anti-Stokes light at any scattering point on the optical fiber into formula (6), the optical power of the anti-Stokes light in the optical fiber loop at the scattering point can be calculated. Formula (6) is the formula for calculating the optical power of the anti-Stokes light in the optical fiber loop based on the zero point at the front end of the optical fiber.

[0044] Formula (6) in, The optical power of the anti-Stokes light in the fiber optic loop at the scattering point under the ambient temperature to be measured. The value is the anti-Stokes power at the front end of the scattering point at the ambient temperature to be measured. The meanings of the other letters in formula (6) are as described above.

[0045] In formula (1) and in formula (5) Substituting into formula (6), we can obtain formula (7).

[0046] Formula (7) The meanings of the letters in formula (7) are as described above.

[0047] Under constant temperature (first preset constant ambient temperature) Under the condition of ), the optical power of the anti-Stokes light in the fiber loop at the scattering point is shown in formula (8).

[0048] Formula (8) in, To the first preset constant ambient temperature Optical power of the anti-Stokes light in the fiber loop at the lower scattering point. To the first preset constant ambient temperature The fiber transmission loss coefficient of the anti-Stokes light at the front end of the lower scattering point, and the meaning of the letters in formula (8) are as described above.

[0049] According to formulas (7) and (8), the optical power ratio of the anti-Stokes light in the fiber loop at the scattering point under the above two ambient temperatures can be calculated, as shown in formulas (9) and (10).

[0050] Formula (9) Formula (10) The meanings of the letters in formulas (9) and (10) are as described above.

[0051] By transforming formula (9), we can obtain the expression for the ambient temperature of the scattering point to be measured, as shown in formula (11).

[0052] Formula (11) in, The ambient temperature to be measured is the scattering point. The meanings of the other letters in formula (11) are as described above. Additionally, in formula (11), the ambient temperature to be measured is the scattering point. and parameters Difference function of fiber transmission loss coefficient of anti-Stokes light All parameters except those mentioned above can be measured.

[0053] Get parameters Difference function of optical fiber transmission loss coefficient for anti-Stokes light The specific implementation process is as follows: At a certain moment, the fiber transmission loss coefficient of anti-Stokes light The optical power measured by the monitoring system can be used for calculation. According to the definition of optical fiber transmission loss coefficient, the transmission loss coefficient of each segment of optical fiber is considered to be the optical fiber transmission loss coefficient of the midpoint of each segment of optical fiber. The optical fiber transmission loss coefficient of the anti-Stokes light at the midpoint of any segment of optical fiber under the ambient temperature to be measured is shown in formula (12). Wherein, any segment of optical fiber refers to the distance between any two adjacent scattering points in the optical fiber, and the midpoint of the optical fiber is the midpoint of any two adjacent scattering points.

[0054] Formula (12) in, Let be the fiber transmission loss coefficient of the anti-Stokes light at the midpoint of any fiber segment under the ambient temperature to be measured. , These are two adjacent scattering points at the ambient temperature to be measured. , The optical power of the front-end anti-Stokes light, , These are the distance coordinates between two adjacent scattering points in the optical fiber. For two adjacent scattering points , The distance coordinates from the midpoint.

[0055] Therefore, Substituting into formula (12) yields the first preset constant ambient temperature. Optical fiber transmission loss coefficient of anti-Stokes light The expression will Substituting the expression and formula (12) into formula (13), we can obtain the difference in fiber transmission loss coefficient at any point in the fiber, that is, the difference between the fiber transmission loss coefficient of the anti-Stokes light at the point in the fiber under the ambient temperature to be measured and the difference between the fiber transmission loss coefficient at the point in the fiber under the first preset constant ambient temperature. The difference between the fiber transmission loss coefficients of the anti-Stokes light and the fiber transmission loss coefficients is shown in formula (13).

[0056] Formula (13) in, The fiber transmission loss coefficient of the anti-Stokes light at the ambient temperature to be measured is compared with the first preset constant ambient temperature. The difference in fiber transmission loss coefficient between the anti-Stokes light and the fiber transmission loss coefficient. , and These are the distance coordinates between two adjacent scattering points in the optical fiber. For two adjacent scattering points and Distance coordinates of the midpoint , These are two adjacent scattering points at the ambient temperature to be measured. and The corresponding front-end anti-Stokes light power, , They are respectively at the first preset constant ambient temperature The two adjacent scattering points and The optical power of the corresponding front-end anti-Stokes light.

[0057] This allows us to obtain the difference in fiber transmission loss coefficient at the midpoints of each fiber segment. By fitting the curve of this difference in fiber transmission loss coefficient at the midpoints of each fiber segment, we can obtain the fiber transmission loss coefficient difference function along the fiber optic line. .

[0058] The difference function of optical fiber transmission loss coefficient along the optical fiber line Substituting these values ​​into formula (10), we can obtain the parameters. The calculated parameters Substituting into formula (11), we can obtain the ambient temperature of the optical fiber at this scattering point.

[0059] Considering the Rayleigh scattering light contained in the anti-Stokes light of Raman scattering, the distance from the fiber front end (i.e., the light emitting end) measured by the monitoring system is... The optical power of the anti-Stokes light at the front end can be expressed by formula (14), and the distance from the fiber front end zero point The optical power of the back-end anti-Stokes light can be expressed as formula (15).

[0060] Formula (14) Formula (15) For any scattering point in the optical fiber, This represents the actual optical power of the anti-Stokes light at the front end of the scattering point. This represents the actual optical power of the anti-Stokes light at the rear end of the scattering point. The optical power of the Rayleigh scattered light is included in the actual optical power of the anti-Stokes light at the front end of the scattering point. The optical power of the Rayleigh scattered light is included in the actual optical power of the anti-Stokes light at the rear of the scattering point. The optical power measurement data for the anti-Stokes light at the front end of the scattering point is a measured value. The optical power measurement data for the back-end Stokes light at the scattering point is a single measurement value. Furthermore, = The optical power of Rayleigh scattered light is not affected by the ambient temperature of the optical fiber, therefore the optical power of subsequent Rayleigh scattered light is used. express.

[0061] Will Substituting into formula (6), we can obtain the result at the first preset constant ambient temperature. Optical power of anti-Stokes light in fiber loop at the lower scattering point , equal .

[0062] According to formula (14), the following can be derived: The calculation formula can be derived from formula (15). The calculation formula.

[0063] Will Substitute to The calculation formula can be obtained. The calculation formula, The calculation formula is .Will Substitute to The calculation formula can be obtained. The calculation formula, The calculation formula is .

[0064] The derived The calculation formula and Replace the formula in formula (6) with the formula for calculation. and Thus, the updated formula (6) is obtained.

[0065] Will The calculation formula and Substituting the calculation formula into From the calculation formula, we can obtain the updated... The calculation formula.

[0066] The updated formula (6) and the updated formula (6) Substituting the calculation formula into formula (11), we can obtain formula (16).

[0067] Formula (16) in, The actual ambient temperature at the scattering point. The coefficients are related to the scattering cross section and wavelength / frequency of the anti-Stokes light. is Planck's constant. The frequency of the fiber molecules in the optical fiber is the vibrational frequency. The first preset constant ambient temperature, The actual optical power of the anti-Stokes light in the fiber optic loop at the scattering point under the first preset constant ambient temperature. This represents the actual optical power of the anti-Stokes light in the fiber optic loop at the scattering point under the actual ambient temperature to be measured. The difference in transmission loss coefficient between anti-Stokes light and actual optical fiber is a function of this difference. This represents the distance from the scattering point to the fiber optic tip. This represents the maximum distance from the back end of the optical fiber to the front end.

[0068] For any scattering point in the optical fiber, the actual ambient temperature of the scattering point can be obtained by substituting the difference function between the actual optical power of the anti-Stokes light in the optical fiber loop and the actual optical fiber transmission loss coefficient of the anti-Stokes light into formula (16).

[0069] The actual ambient temperature of several scattering points in an optical fiber together constitutes the actual ambient temperature along the optical fiber.

[0070] In this application, the actual optical power of the anti-Stokes light in the fiber optic loop at the scattering point is obtained by filtering the Rayleigh scattering light power contained in the optical power measurement data of the anti-Stokes light at the scattering point. This improves the signal-to-noise ratio of the anti-Stokes light signal, thereby making the actual ambient temperature at the scattering point calculated based on the actual optical power of the anti-Stokes light in the fiber optic loop more accurate. Furthermore, this improves the accuracy of temperature measurement along the fiber optic line. In addition, this application achieves high-precision temperature measurement without relying on extremely high-performance, high-cost optical filters during fiber optic line temperature measurement, significantly reducing hardware complexity and manufacturing costs, and enhancing the reliability of temperature measurement.

[0071] Furthermore, in some embodiments of this application, step 101 may also include the following steps: Step 1011: For any scattering point in the optical fiber, acquire the optical power measurement data of the front-end anti-Stokes light, the optical power measurement data of the rear-end anti-Stokes light, and the optical power of the Rayleigh scattered light at the scattering point.

[0072] Step 1012: Determine the actual optical power of the anti-Stokes light at the front end of the scattering point based on the measured optical power data of the anti-Stokes light at the front end of the scattering point and the optical power of the Rayleigh scattered light.

[0073] Step 1013: Determine the actual optical power of the back-end anti-Stokes light at the scattering point based on the measured optical power data of the back-end anti-Stokes light and the optical power of the Rayleigh scattered light.

[0074] Step 1014: Determine the actual optical power of the anti-Stokes light in the fiber loop at the scattering point based on the actual optical power of the anti-Stokes light at the front end of the scattering point and the actual optical power of the anti-Stokes light at the rear end of the scattering point.

[0075] In some embodiments of this application, for any scattering point in the optical fiber, the optical power measurement data of the front-end anti-Stokes light, the optical power measurement data of the back-end anti-Stokes light, and the optical power of Rayleigh scattered light included in the actual optical power of the front-end anti-Stokes light are obtained. The optical power of Rayleigh scattered light included in the actual optical power of the front-end anti-Stokes light is noise power and needs to be filtered out.

[0076] By substituting the measured optical power data of the anti-Stokes light at the front end of the scattering point and the optical power of the Rayleigh scattered light included in the actual optical power of the anti-Stokes light at the front end of the scattering point into formula (14), the actual optical power of the anti-Stokes light at the front end of the scattering point can be calculated.

[0077] By substituting the measured optical power data of the anti-Stokes light at the rear end of the scattering point and the optical power of the Rayleigh scattered light included in the actual optical power of the anti-Stokes light at the front end of the scattering point into formula (15), the actual optical power of the anti-Stokes light at the rear end of the scattering point can be calculated.

[0078] The actual optical power of the anti-Stokes light in the fiber loop at the scattering point can be obtained by geometrically averaging the actual optical power of the anti-Stokes light at the front end of the scattering point and the actual optical power of the anti-Stokes light at the rear end of the scattering point.

[0079] Furthermore, in some embodiments of this application, step 101 may also include the following steps: Step 1015: For the midpoint of any two adjacent scattering points in the optical fiber, obtain the difference in the actual optical fiber transmission loss coefficient between the midpoints of the two adjacent scattering points.

[0080] Step 1016: Determine the actual fiber transmission loss coefficient difference function of the anti-Stokes light based on the actual fiber transmission loss coefficient difference between the midpoints of two adjacent scattering points.

[0081] In some embodiments of this application, the difference in the actual fiber transmission loss coefficient between the midpoints of any two adjacent scattering points in the optical fiber is obtained.

[0082] By fitting a curve to the difference in the actual fiber transmission loss coefficient between the midpoints of all two adjacent scattering points in the fiber, the actual fiber transmission loss coefficient difference function of anti-Stokes light can be obtained.

[0083] Furthermore, in some embodiments of this application, step 1015 may also include the following steps: Sub-step 11: Obtain the actual optical power of the front-end anti-Stokes light at two adjacent scattering points under the ambient temperature to be measured, and the actual optical power of the front-end anti-Stokes light at two adjacent scattering points under the first preset constant ambient temperature.

[0084] Sub-step 12: Based on the actual optical power of the front-end anti-Stokes light of two adjacent scattering points at the ambient temperature to be measured and the actual optical power of the front-end anti-Stokes light of two adjacent scattering points at the first preset constant ambient temperature, determine the difference in the actual optical fiber transmission loss coefficient at the midpoint of two adjacent scattering points.

[0085] In some embodiments of this application, the actual optical power of the front-end anti-Stokes light corresponding to each of two adjacent scattering points at the ambient temperature to be measured and the actual optical power of the front-end anti-Stokes light corresponding to each of two adjacent scattering points at a first preset constant ambient temperature are obtained.

[0086] By substituting the actual optical power of the front-end anti-Stokes light corresponding to each of the two adjacent scattering points under the ambient temperature to be measured and the actual optical power of the front-end anti-Stokes light corresponding to each of the two adjacent scattering points under the first preset constant ambient temperature into formula (17), the difference in the actual optical fiber transmission loss coefficient at the midpoint of the two adjacent scattering points can be calculated.

[0087] Formula (17) in, This represents the difference in the actual fiber transmission loss coefficient at the midpoint between two adjacent scattering points. , These are two adjacent scattering points at the ambient temperature to be measured. , The actual optical power of the corresponding front-end anti-Stokes beam, , These are two adjacent scattering points under the first preset constant ambient temperature. , The actual optical power of the corresponding front-end anti-Stokes beam.

[0088] Furthermore, in some embodiments of this application, the method may further include the following steps: Step 104: Obtain the optical power of the Rayleigh scattered light at the scattering point.

[0089] In some embodiments of this application, in order to filter out the optical power of Rayleigh scattered light, the optical power of Rayleigh scattered light included in the actual optical power of the anti-Stokes light at the front end of the scattering point can be calculated in advance.

[0090] Furthermore, in some embodiments of this application, step 104 may also include the following steps: Step 1041: Obtain a function related to the second preset constant ambient temperature, wherein the first preset constant ambient temperature is less than the second preset constant ambient temperature.

[0091] Step 1042: Determine the optical power of the Rayleigh scattered light at the scattering point based on a function related to the second preset constant ambient temperature.

[0092] In some embodiments of this application, a function related to a second preset constant ambient temperature is obtained, wherein the first preset constant ambient temperature is less than the second preset constant ambient temperature, and the second preset constant ambient temperature can be used... This indicates that the temperature difference between the first preset constant ambient temperature and the second preset constant ambient temperature must be greater than 30℃ or 30K.

[0093] The Rayleigh scattering power is included in the actual optical power of the anti-Stokes light at the front end of the scattering point, which is determined by a function related to the second preset constant ambient temperature.

[0094] Furthermore, in some embodiments of this application, step 1041 may also include the following steps: Sub-step 21: Obtain the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under the second preset constant ambient temperature and the actual fiber transmission loss coefficient difference function of the first anti-Stokes light. The actual fiber transmission loss coefficient difference function of the first anti-Stokes light is obtained based on the fiber transmission loss coefficient difference between the fiber transmission loss coefficient of the anti-Stokes light at the midpoint of two adjacent scattering points under the first preset constant ambient temperature and the fiber transmission loss coefficient of the anti-Stokes light at the midpoint of two adjacent scattering points under the second preset constant ambient temperature.

[0095] Sub-step 22: Based on the second preset constant ambient temperature, the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under the first preset constant ambient temperature, the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under the second preset constant ambient temperature, and the difference function of the actual fiber transmission loss coefficient of the first anti-Stokes light, determine the function related to the second preset constant ambient temperature.

[0096] In some embodiments of this application, the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under a second preset constant ambient temperature and the difference function of the actual fiber transmission loss coefficient of the first anti-Stokes light are obtained.

[0097] Based on the second preset constant ambient temperature, the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under the first preset constant ambient temperature, the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under the second preset constant ambient temperature, and the difference function of the actual fiber transmission loss coefficient of the first anti-Stokes light, a function related to the second preset constant ambient temperature can be obtained, as shown in formula (18).

[0098] Formula (18) in, The second preset constant ambient temperature, The coefficients are related to the scattering cross section and wavelength / frequency of the anti-Stokes light. is Planck's constant. The frequency of the fiber molecules in the optical fiber is the vibrational frequency. The first preset constant ambient temperature, To determine the actual optical power of the anti-Stokes light in the fiber optic loop at the scattering point under the first preset constant ambient temperature, The actual optical power of the anti-Stokes light in the fiber optic loop at the scattering point under the second preset constant ambient temperature. The difference function is the actual optical fiber transmission loss coefficient of the first anti-Stokes light.

[0099] The actual fiber transmission loss coefficient difference function of the first anti-Stokes light is calculated based on the difference between the fiber transmission loss coefficients of the anti-Stokes light at the midpoint of two adjacent scattering points under a first preset constant ambient temperature and the anti-Stokes light at the midpoint of two adjacent scattering points under a second preset constant ambient temperature. Specifically, for any midpoint of two adjacent scattering points in the fiber, the difference between the fiber transmission loss coefficients of the anti-Stokes light at the midpoint of two adjacent scattering points under the first preset constant ambient temperature and the anti-Stokes light at the midpoint of two adjacent scattering points under the second preset constant ambient temperature is calculated. From this, the fiber transmission loss coefficient difference between the midpoints of each pair of adjacent scattering points in the fiber can be obtained. By curve fitting the fiber transmission loss coefficient difference between the midpoints of each pair of adjacent scattering points, the actual fiber transmission loss coefficient difference function of the first anti-Stokes light can be obtained.

[0100] Among them, for the midpoint of any two adjacent scattering points in the optical fiber, the difference between the optical fiber transmission loss coefficient of the anti-Stokes light at the midpoint of the two adjacent scattering points under the first preset constant ambient temperature and the optical fiber transmission loss coefficient of the anti-Stokes light at the midpoint of the two adjacent scattering points under the second preset constant ambient temperature can be expressed as formula (19).

[0101] Formula (19) in, The fiber transmission loss coefficient is the difference between the fiber transmission loss coefficient of the anti-Stokes light at the midpoint of two adjacent scattering points under a first preset constant ambient temperature and the fiber transmission loss coefficient of the anti-Stokes light at the midpoint of two adjacent scattering points under a second preset constant ambient temperature. and They are respectively at the first preset constant ambient temperature The two adjacent scattering points below and The optical power measurement data of the front-end anti-Stokes light, and They are respectively at the second preset constant ambient temperature The two adjacent scattering points below and The optical power measurement data of the front-end anti-Stokes light, and These are two adjacent scattering points. and The optical power of Rayleigh scattered light, .

[0102] Furthermore, in some embodiments of this application, step 1042 may also include the following steps: Sub-step 31 involves transforming the function related to the second preset constant ambient temperature to obtain a first parameter and a second parameter. The first parameter is determined based on the optical power measurement data of the front-end anti-Stokes light of any two adjacent scattering points under the first preset constant ambient temperature, the optical power measurement data of the front-end anti-Stokes light of any two adjacent scattering points under the second preset constant ambient temperature, and the optical power of the Rayleigh scattered light of any two adjacent scattering points. The second parameter is determined based on the optical power measurement data of the front-end and rear-end anti-Stokes light of the scattering points under the first preset constant ambient temperature, the optical power measurement data of the front-end and rear-end anti-Stokes light of the scattering points under the second preset constant ambient temperature, and the optical power of the Rayleigh scattered light of the scattering points.

[0103] Sub-step 32: Determine the error function based on the first parameter and the second parameter.

[0104] Sub-step 33: Determine the optical power of the Rayleigh scattered light at the scattering point based on the error function.

[0105] In some embodiments of this application, the function formula (18) related to the second preset constant ambient temperature is transformed to obtain formula (20) and formula (21).

[0106] Formula (20) Formula (21) in, The letter is a constant, and the meanings of the other letters in formulas (20) and (21) are as described above.

[0107] The problem is discretized, and the nonlinear equations are solved numerically. The solution steps are as follows: Step 1: Divide the interval Divided into Sub-intervals, scattering points Define an unknown vector, which represents the Rayleigh scattered light power contained in the anti-Stokes light power measurement data at each scattering point. ,in, .

[0108] Step 2: Discretize the integral and define the parameters. The left side of equation (20) is transformed into equations (22) and (23).

[0109] Formula (22) Formula (23) The right side of formula (20) for each There is formula (24).

[0110] Formula (24) Step 3: Based on formulas (22) and (24), the error equation is determined as formula (25).

[0111] Formula (25) The objective is to solve .have A system of equations and There are several unknowns, and the solution to the equations is unique. Due to the nonlinearity of the system of equations, the numerical method Newton's iteration method is used to solve it.

[0112] Solve for all unknowns Then, by substituting into formula (16), the actual ambient temperature of each scattering point can be obtained after filtering out the optical power of the Rayleigh scattered light contained in the optical power measurement data of the anti-Stokes light of the scattering point.

[0113] Corresponding to the method provided in the above-described embodiment of the optical fiber temperature measurement method of this application, see [link to relevant documentation]. Figure 2 This application also provides a device block diagram for a fiber optic temperature measurement device. In this embodiment, the device includes: The data acquisition module 201 is used to acquire the actual optical power of the anti-Stokes light in the fiber loop at each scattering point in the optical fiber and the difference function of the actual fiber transmission loss coefficient of the anti-Stokes light; wherein, the actual optical power of the anti-Stokes light in the fiber loop at the scattering point is obtained by filtering out the optical power of the Rayleigh scattered light at the scattering point from the optical power measurement data of the anti-Stokes light at the scattering point, and the actual optical power of the anti-Stokes light in the fiber loop at the scattering point includes the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under a first preset constant ambient temperature and the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under the actual ambient temperature to be measured; The actual ambient temperature determination module 202 for scattering point is used to determine the actual ambient temperature of any scattering point in the optical fiber based on the difference function between the actual optical power of the anti-Stokes light in the optical fiber loop and the actual optical fiber transmission loss coefficient of the anti-Stokes light. The actual ambient temperature acquisition module 203 along the optical fiber is used to determine the actual ambient temperature of the optical fiber based on the actual ambient temperature of each scattering point in the optical fiber.

[0114] Optionally, the optical power measurement data of the anti-Stokes light at the scattering point includes the optical power measurement data of the front-end anti-Stokes light and the optical power measurement data of the rear-end anti-Stokes light at the scattering point; Data acquisition module 201 includes: The data acquisition submodule is used to acquire the optical power measurement data of the front-end anti-Stokes light, the back-end anti-Stokes light, and the Rayleigh scattered light for any scattering point in the optical fiber. The first actual optical power determination submodule is used to determine the actual optical power of the anti-Stokes light at the front end of the scattering point based on the optical power measurement data of the anti-Stokes light at the front end of the scattering point and the optical power of the Rayleigh scattering light. The second actual optical power determination submodule is used to determine the actual optical power of the back-end anti-Stokes light at the scattering point based on the optical power measurement data of the back-end anti-Stokes light and the optical power of the Rayleigh scattering light. The third actual optical power determination submodule is used to determine the actual optical power of the anti-Stokes light in the fiber loop at the scattering point based on the actual optical power of the anti-Stokes light at the front end of the scattering point and the actual optical power of the anti-Stokes light at the rear end of the scattering point.

[0115] Optionally, the data acquisition module 201 includes: The actual fiber transmission loss coefficient difference acquisition submodule is used to obtain the actual fiber transmission loss coefficient difference between the midpoints of any two adjacent scattering points in the fiber. The actual fiber transmission loss coefficient difference function determination submodule is used to determine the actual fiber transmission loss coefficient difference function of the anti-Stokes light based on the difference in actual fiber transmission loss coefficients at the midpoints of two adjacent scattering points.

[0116] Optionally, the submodule for obtaining the actual fiber transmission loss coefficient difference includes: The actual optical power acquisition unit is used to acquire the actual optical power of the front-end anti-Stokes light at two adjacent scattering points under the ambient temperature to be measured, and the actual optical power of the front-end anti-Stokes light at two adjacent scattering points under a first preset constant ambient temperature. The actual fiber transmission loss coefficient difference determination unit is used to determine the actual fiber transmission loss coefficient difference between the midpoints of two adjacent scattering points based on the actual optical power of the front-end anti-Stokes light of two adjacent scattering points under the ambient temperature to be measured and the actual optical power of the front-end anti-Stokes light of two adjacent scattering points under the first preset constant ambient temperature.

[0117] Optionally, the actual fiber transmission loss coefficient difference determination unit includes:

[0118] in, This represents the difference in the actual fiber transmission loss coefficient at the midpoint between two adjacent scattering points. , These are two adjacent scattering points at the ambient temperature to be measured. , The actual optical power of the front-end anti-Stokes light, , These are two adjacent scattering points under the first preset constant ambient temperature. , The actual optical power of the front-end anti-Stokes light.

[0119] Optionally, the module 202 for determining the actual ambient temperature of the scattering point includes:

[0120] in, The actual ambient temperature at the scattering point. The coefficients are related to the scattering cross section and wavelength / frequency of the anti-Stokes light. is Planck's constant. The frequency of the fiber molecules in the optical fiber is the vibrational frequency. The first preset constant ambient temperature, The actual optical power of the anti-Stokes light in the fiber optic loop at the scattering point under the first preset constant ambient temperature. This represents the actual optical power of the anti-Stokes light in the fiber optic loop at the scattering point under the actual ambient temperature to be measured. The difference in transmission loss coefficient between anti-Stokes light and actual optical fiber is a function of this difference. This represents the distance from the scattering point to the fiber optic tip. This represents the maximum distance from the back end of the optical fiber to the front end.

[0121] Optionally, the device further includes: The optical power acquisition module for Rayleigh scattered light to be filtered out is used to acquire the optical power of Rayleigh scattered light at the scattering point.

[0122] Optionally, the optical power acquisition module for the Rayleigh scattered light to be filtered out includes: The temperature function acquisition submodule is used to acquire functions related to the second preset constant ambient temperature, where the first preset constant ambient temperature is less than the second preset constant ambient temperature; The submodule for determining the optical power of the Rayleigh scattered light to be filtered out is used to determine the optical power of the Rayleigh scattered light at the scattering point based on a function related to a second preset constant ambient temperature.

[0123] Optionally, the temperature function acquisition submodule includes: The relevant data acquisition unit at the second preset temperature is used to acquire the actual optical power of the anti-Stokes light in the optical fiber loop at the scattering point at the second preset constant ambient temperature and the actual optical fiber transmission loss coefficient difference function of the first anti-Stokes light. The actual optical fiber transmission loss coefficient difference function of the first anti-Stokes light is obtained based on the difference in optical fiber transmission loss coefficient between the optical fiber transmission loss coefficient of the anti-Stokes light at the midpoint of two adjacent scattering points at the first preset constant ambient temperature and the optical fiber transmission loss coefficient of the anti-Stokes light at the midpoint of two adjacent scattering points at the second preset constant ambient temperature. The temperature function determination unit is used to determine a function related to the second preset constant ambient temperature based on the second preset constant ambient temperature, the actual optical power of the anti-Stokes light in the fiber loop at the scattering point at the first preset constant ambient temperature, the actual optical power of the anti-Stokes light in the fiber loop at the scattering point at the second preset constant ambient temperature, and the difference function of the actual fiber transmission loss coefficient of the first anti-Stokes light.

[0124] Optionally, the temperature function determination unit includes:

[0125] in, The second preset constant ambient temperature, The coefficients are related to the scattering cross section and wavelength / frequency of the anti-Stokes light. is Planck's constant. The frequency of the fiber molecules in the optical fiber is the vibrational frequency. The first preset constant ambient temperature, To determine the actual optical power of the anti-Stokes light in the fiber optic loop at the scattering point under the first preset constant ambient temperature, The actual optical power of the anti-Stokes light in the fiber optic loop at the scattering point under the second preset constant ambient temperature. The difference function is the actual optical fiber transmission loss coefficient of the first anti-Stokes light.

[0126] Optionally, the optical power determination submodule for the Rayleigh scattered light to be filtered out includes: The function conversion unit is used to convert the function related to the second preset constant ambient temperature to obtain a first parameter and a second parameter. The first parameter is determined based on the optical power measurement data of the front anti-Stokes light of any two adjacent scattering points under the first preset constant ambient temperature, the optical power measurement data of the front anti-Stokes light of any two adjacent scattering points under the second preset constant ambient temperature, and the optical power of the Rayleigh scattered light of any two adjacent scattering points. The second parameter is determined based on the optical power measurement data of the front anti-Stokes light and the rear anti-Stokes light of the scattering points under the first preset constant ambient temperature, the optical power measurement data of the front anti-Stokes light and the rear anti-Stokes light of the scattering points under the second preset constant ambient temperature, and the optical power of the Rayleigh scattered light of the scattering points. The error function determination unit is used to determine the error function based on the first parameter and the second parameter. The Rayleigh scattering light power determination unit is used to determine the Rayleigh scattering light power at the scattering point based on the error function.

[0127] Figure 3 This is a structural diagram of an electronic device M00 provided in an embodiment of this application. In the diagram, the electronic device M00 includes a processor M01 and a memory M02. The memory M02 stores a program or instructions that can run on the processor M01. When the program or instructions are executed by the processor M01, they implement the various steps of the above-described embodiment of the fiber optic temperature measurement method and achieve the same technical effect. To avoid repetition, they will not be described again here.

[0128] In embodiments of this application, the memory M02 can be used to store software programs and various data. The memory M02 may primarily include a first storage area for storing programs or instructions and a second storage area for storing data. The first storage area may store the operating system, applications or instructions required for at least one function (such as sound playback, image playback, etc.). Furthermore, the memory M02 may include volatile memory or non-volatile memory, or both. The non-volatile memory may be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. Volatile memory can be random access memory (RAM), static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDRSDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM), and direct memory bus RAM (DRRAM). The memory M02 in the embodiments of this application includes, but is not limited to, these and any other suitable types of memory.

[0129] The processor M01 may include one or more processing units; optionally, the processor M01 integrates an application processor and a modem processor, wherein the application processor mainly handles operations involving the operating system, user interface, and applications, and the modem processor mainly handles wireless communication signals, such as a baseband processor. It is understood that the aforementioned modem processor may also not be integrated into the processor M01.

[0130] This application also provides a readable storage medium storing a program or instructions. When the program or instructions are executed by a processor, they implement the various processes of the above-described optical fiber temperature measurement method embodiments and achieve the same technical effect. To avoid repetition, they will not be described again here.

[0131] The processor is the processor in the electronic device described in the above embodiments. The readable storage medium includes computer-readable storage media, such as computer read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk.

[0132] This application embodiment also provides a chip, which includes a processor and a communication interface. The communication interface is coupled to the processor. The processor is used to run programs or instructions to implement the various processes of the above-described fiber optic temperature measurement method embodiment, and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0133] It should be understood that the chip mentioned in the embodiments of this application may also be referred to as a system-on-a-chip, system chip, chip system, or system-on-a-chip, etc.

[0134] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0135] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, 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 is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0136] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A method for measuring temperature along an optical fiber, characterized in that, The method includes: The difference function between the actual optical power of the anti-Stokes light in the fiber loop and the actual fiber transmission loss coefficient of the anti-Stokes light at each scattering point in the optical fiber is obtained. The actual optical power of the anti-Stokes light in the fiber loop at each scattering point is obtained by filtering out the Rayleigh scattered light power from the optical power measurement data of the anti-Stokes light at the scattering point. The actual optical power of the anti-Stokes light in the fiber loop at each scattering point includes the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under a first preset constant ambient temperature and the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under the actual ambient temperature to be measured. For any of the scattering points in the optical fiber, the actual ambient temperature of the scattering point is determined based on the difference function between the actual optical power of the anti-Stokes light in the optical fiber loop at the scattering point and the actual optical fiber transmission loss coefficient of the anti-Stokes light. The actual ambient temperature of the optical fiber is determined based on the actual ambient temperature of each scattering point in the optical fiber.

2. The method according to claim 1, characterized in that, The optical power measurement data of the anti-Stokes light at the scattering point includes the optical power measurement data of the front-end anti-Stokes light and the optical power measurement data of the rear-end anti-Stokes light at the scattering point; The actual optical power of the anti-Stokes light in the fiber loop at each scattering point in the fiber includes: For any scattering point in the optical fiber, acquire the optical power measurement data of the front-end anti-Stokes light, the optical power measurement data of the rear-end anti-Stokes light, and the optical power of the Rayleigh scattered light at the scattering point; The actual optical power of the anti-Stokes light at the front end of the scattering point is determined based on the optical power measurement data of the anti-Stokes light at the scattering point and the optical power of the Rayleigh scattered light. Based on the optical power measurement data of the back-end anti-Stokes light at the scattering point and the optical power of the Rayleigh scattered light, determine the actual optical power of the back-end anti-Stokes light at the scattering point; The actual optical power of the anti-Stokes light in the fiber optic loop at the scattering point is determined based on the actual optical power of the anti-Stokes light at the front end of the scattering point and the actual optical power of the anti-Stokes light at the rear end of the scattering point.

3. The method according to claim 1, characterized in that, The actual fiber transmission loss coefficient difference function for obtaining anti-Stokes light includes: For the midpoint of any two adjacent scattering points in the optical fiber, obtain the difference in the actual optical fiber transmission loss coefficient between the midpoints of the two adjacent scattering points. The actual fiber transmission loss coefficient difference function of the anti-Stokes light is determined based on the difference in the actual fiber transmission loss coefficient at the midpoint of the two adjacent scattering points.

4. The method according to claim 3, characterized in that, The step of obtaining the actual fiber transmission loss coefficient difference between the midpoints of the two adjacent scattering points includes: The actual optical power of the anti-Stokes light at the front end of two adjacent scattering points is obtained at the ambient temperature to be measured, and the actual optical power of the anti-Stokes light at the front end of two adjacent scattering points is obtained at a first preset constant ambient temperature. The difference in the actual optical fiber transmission loss coefficient at the midpoint of the two adjacent scattering points is determined based on the actual optical power of the anti-Stokes light at the front end of the two adjacent scattering points under the measured ambient temperature and the actual optical power of the anti-Stokes light at the front end of the two adjacent scattering points under the first preset constant ambient temperature.

5. The method according to claim 4, characterized in that, The step of determining the difference in the actual fiber transmission loss coefficient at the midpoint of the two adjacent scattering points based on the actual optical power of the anti-Stokes light at the front end of the two adjacent scattering points under the ambient temperature to be measured and the actual optical power of the anti-Stokes light at the front end of the two adjacent scattering points under the first preset constant ambient temperature includes: in, The difference in the actual fiber transmission loss coefficient between the midpoints of the two adjacent scattering points. , These are two adjacent scattering points at the ambient temperature to be measured. , The actual optical power of the front-end anti-Stokes light, , The two adjacent scattering points are respectively under the first preset constant ambient temperature. , The actual optical power of the front-end anti-Stokes light.

6. The method according to claim 1, characterized in that, The step of determining the actual ambient temperature of the scattering point based on the difference function between the actual optical power of the anti-Stokes light in the fiber loop at the scattering point and the actual fiber transmission loss coefficient of the anti-Stokes light includes: in, The actual ambient temperature at the scattering point. The coefficients are related to the scattering cross section and wavelength / frequency of the anti-Stokes light. is Planck's constant. The frequency of the fiber molecules in the optical fiber is the vibration frequency. The first preset constant ambient temperature, The actual optical power of the anti-Stokes light in the fiber optic loop at the scattering point is given by the first preset constant ambient temperature. The actual optical power of the anti-Stokes light in the fiber optic loop at the scattering point is given at the actual ambient temperature to be measured. The difference function is the actual fiber transmission loss coefficient of the anti-Stokes light. The distance from the scattering point to the fiber optic tip is [distance]. This represents the maximum distance from the back end of the optical fiber to the front end.

7. The method according to claim 1, characterized in that, Before the step of obtaining the difference function between the actual optical power of the anti-Stokes light in the fiber loop and the actual fiber transmission loss coefficient of the anti-Stokes light at each scattering point in the fiber, the method further includes: Obtain the optical power of the Rayleigh scattered light at the scattering point.

8. The method according to claim 7, characterized in that, The optical power of the Rayleigh scattered light at the scattering point includes: Obtain a function related to a second preset constant ambient temperature, wherein the first preset constant ambient temperature is less than the second preset constant ambient temperature; The optical power of the Rayleigh scattered light at the scattering point is determined based on the function related to the second preset constant ambient temperature.

9. The method according to claim 8, characterized in that, The function for obtaining the second preset constant ambient temperature includes: The actual optical power of the anti-Stokes light in the fiber loop at the scattering point and the actual fiber transmission loss coefficient difference function of the first anti-Stokes light are obtained under the second preset constant ambient temperature. The actual fiber transmission loss coefficient difference function of the first anti-Stokes light is obtained based on the fiber transmission loss coefficient difference between the fiber transmission loss coefficient of the anti-Stokes light at the midpoint of the two adjacent scattering points under the first preset constant ambient temperature and the fiber transmission loss coefficient of the anti-Stokes light at the midpoint of the two adjacent scattering points under the second preset constant ambient temperature. Based on the second preset constant ambient temperature, the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under the first preset constant ambient temperature, the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under the second preset constant ambient temperature, and the difference function of the actual fiber transmission loss coefficient of the first anti-Stokes light, a function related to the second preset constant ambient temperature is determined.

10. The method according to claim 9, characterized in that, The function determined based on the second preset constant ambient temperature, the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under the first preset constant ambient temperature, the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under the second preset constant ambient temperature, and the difference function of the actual fiber transmission loss coefficient of the first anti-Stokes light, includes: in, The second preset constant ambient temperature, The coefficients are related to the scattering cross section and wavelength / frequency of the anti-Stokes light. is Planck's constant. The frequency of the fiber molecules in the optical fiber is the vibration frequency. The first preset constant ambient temperature, To determine the actual optical power of the anti-Stokes light in the fiber optic loop at the scattering point under a first preset constant ambient temperature, The actual optical power of the anti-Stokes light in the fiber optic loop at the scattering point is given by the second preset constant ambient temperature. The difference function is the actual optical fiber transmission loss coefficient of the first anti-Stokes light.

11. The method according to claim 8, characterized in that, The determination of the Rayleigh scattered light power at the scattering point based on the function related to the second preset constant ambient temperature includes: The function related to the second preset constant ambient temperature is transformed to obtain a first parameter and a second parameter. The first parameter is determined based on the optical power measurement data of the front anti-Stokes light of any two adjacent scattering points under the first preset constant ambient temperature, the optical power measurement data of the front anti-Stokes light of any two adjacent scattering points under the second preset constant ambient temperature, and the optical power of the Rayleigh scattered light of any two adjacent scattering points. The second parameter is determined based on the optical power measurement data of the front anti-Stokes light and the rear anti-Stokes light of the scattering point under the first preset constant ambient temperature, the optical power measurement data of the front anti-Stokes light and the rear anti-Stokes light of the scattering point under the second preset constant ambient temperature, and the optical power of the Rayleigh scattered light of the scattering point. Determine the error function based on the first parameter and the second parameter; The optical power of the Rayleigh scattered light at the scattering point is determined based on the error function.

12. A fiber optic temperature measurement device, characterized in that, The fiber optic temperature measurement device includes: The data acquisition module is used to acquire the actual optical power of the anti-Stokes light in the fiber loop at each scattering point in the optical fiber and the difference function of the actual fiber transmission loss coefficient of the anti-Stokes light; wherein, the actual optical power of the anti-Stokes light in the fiber loop at the scattering point is obtained by filtering out the optical power of the Rayleigh scattered light at the scattering point from the optical power measurement data of the anti-Stokes light at the scattering point, and the actual optical power of the anti-Stokes light in the fiber loop at the scattering point includes the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under a first preset constant ambient temperature and the actual optical power of the anti-Stokes light in the fiber loop at the scattering point under the actual ambient temperature to be measured; The module for determining the actual ambient temperature of a scattering point is used to determine the actual ambient temperature of any scattering point in the optical fiber based on the difference function between the actual optical power of the anti-Stokes light in the optical fiber loop and the actual optical fiber transmission loss coefficient of the anti-Stokes light. The module for acquiring the actual ambient temperature along the optical fiber is used to determine the actual ambient temperature of the optical fiber based on the actual ambient temperature of each scattering point in the optical fiber.

13. An electronic device, characterized in that, It includes a processor, a memory, and a program or instructions stored in the memory and executable on the processor, wherein the program or instructions, when executed by the processor, implement the steps of the fiber optic temperature measurement method as described in any one of claims 1-11.

14. A readable storage medium, characterized in that, The readable storage medium stores a program or instructions that, when executed by a processor, implement the steps of the fiber optic temperature measurement method as described in any one of claims 1-11.

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