WO2018045965A1 - Device and method for detecting optical fiber event point - Google Patents

Abstract

A device and method for detecting an optical fiber event point. The device comprises: a wavelet calculation module configured as to perform a wavelet calculation on signal data of a backscattered light and a reflected light of a detecting light pulse in an optical fiber and then to produce signal squared data by squaring; a window division module configured as to divide the signal squared data into a preset number of detection windows; and an event point detection module configured as to search for an event point in the multiple detection windows.

Description

Device and method for detecting fiber event points Technical field

The present disclosure relates to the field of fiber optic inspection, for example, to an apparatus and method for detecting fiber event points.

Background technique

The Optical Time Domain Reflectometer (OTDR) can detect the event points by using the principle of reflection and scattering of light. It can be used to test the attenuation of the entire fiber link and provide length-dependent attenuation details. Detecting, locating, and measuring events anywhere on the fiber link (incidents are defects due to splices, connectors, bends, etc. in the fiber link, and changes in the optical transmission characteristics of the event can be measured). The non-destructive, one-end access and intuitive speed of OTDR testing make OTDR an indispensable instrument in the production, construction and maintenance of fiber optic cable.

Light will be lost during transmission, and the loss will be very large in the long distance. Therefore, the OTDR cannot detect or miss the detection of the event point when performing long-distance fiber inspection.

Summary of the invention

The present disclosure provides an apparatus and method for detecting an optical fiber event point, which can solve the problem that an OTDR cannot detect or leak an event point when performing long-distance fiber inspection.

A device for detecting a fiber event point, comprising:

The wavelet calculation module is configured to perform wavelet operation on the signal data of the backscattered light and the reflected light of the detected optical pulse in the optical fiber, and then squared to obtain the squared data of the signal;

a window dividing module is configured to divide the square data of the signal into n segments, and each segment corresponds to a detection window; wherein n is a natural number greater than 1;

The event point detection module is configured to search for event points in a plurality of the detection windows, respectively.

Optionally, the event point detection module includes multiple sub-detection modules; one of the sub-detections The module corresponds to one of the detection windows;

Each of the sub-detection modules is configured to search for the relationship between the check threshold of the detection window corresponding to the sub-detection module and the squared data of the signal in the detection window corresponding to the sub-detection module. The event points in the window are detected; wherein the check thresholds of the plurality of detection windows are different from each other.

Optionally, each of the sub-detection modules is configured to sort the squared data of the signals in the detection window corresponding to the sub-detection module from large to small, and start from the maximum signal squared data, according to the sorting selection. Setting a quantity of the signal squared data for an average calculation;

Using the calculated average value as the inspection threshold;

The signal squared data in the detection window that is larger than the set threshold of the inspection threshold is used as the event point.

Optionally, the device further includes:

An optical pulse generation module configured to generate the detection light pulse using a Gray complementary sequence and incident on the optical fiber;

a data sampling module configured to receive the backscattered light and the reflected light of the detection light pulse, and convert the received backscattered light and the reflected light optical signal into an electrical signal;

a voltage loss conversion module configured to convert the electrical signal into a loss;

And an operation module configured to calculate the loss of the conversion and the Gray complementary sequence to obtain signal data of the backscattered light and the reflected light.

Optionally, the optical pulse generating module is further configured to set the number of bits of the Gray complementary sequence according to the detection distance of the optical fiber.

Optionally, the wavelet calculation module is configured to perform wavelet operation on signal data of the backscattered light and the reflected light to obtain high frequency partial data after wavelet operation;

The high frequency portion data is squared to obtain signal squared data.

A method of detecting an optical fiber event point, comprising:

Performing a wavelet operation on the signal data of the backscattered light and the reflected light of the detected optical pulse in the optical fiber, and performing squared to obtain the squared data of the signal;

Dividing the signal squared data into n segments, each segment correspondingly setting a detection window; wherein n is a natural number greater than 1;

Find event points in a plurality of said detection windows, respectively.

Optionally, the searching for event points in the plurality of the detection windows respectively includes:

In each of the detection windows, searching for an event point in the detection window according to a relationship between a check threshold of the detection window and the squared data of the signal in the detection window; wherein, the plurality of The check thresholds of the detection windows are different from each other.

Optionally, searching for the event point in the detection window according to the relationship between the check threshold of the detection window and the squared data of the signal in the detection window includes:

Aligning the squared data of the signals in the detection window according to the largest to the smallest, and starting from the maximum signal squared data, selecting a set number of signal squared data according to the sorting to perform an average calculation;

Using the calculated average value as the inspection threshold;

The signal squared data in the detection window that is larger than the set threshold of the inspection threshold is used as the event point.

Optionally, before performing the wavelet operation on the signal data of the backscattered light and the reflected light for detecting the optical pulse in the optical fiber, the method further includes:

Generating the detection light pulse using a Gray complementary sequence and incident on the optical fiber;

Receiving the backscattered light and the reflected light of the detecting light pulse, and converting the received backscattered light and the reflected light optical signal into an electrical signal;

The electrical signal is converted into a loss, and the loss is computed with the Gray complementary sequence to obtain signal data of the backscattered light and the reflected light.

Optionally, the method further includes:

The number of bits of the Gray complementary sequence is set according to the detection distance of the optical fiber.

Optionally, performing wavelet processing on the signal data of the backscattered light and the reflected light of the detected optical pulse in the optical fiber, and performing squared to obtain the squared data of the signal, including:

The backscattered light of the detection light pulse and the signal data of the reflected light in the optical fiber Perform wavelet operation to obtain high frequency part data after wavelet operation;

The high frequency portion data is squared to obtain signal squared data.

The embodiment further provides a computer readable storage medium storing computer executable instructions for performing the above method for detecting a fiber event point.

The embodiment also provides an electronic device including one or more processors, a memory, and one or more programs, the one or more programs being stored in the memory when executed by one or more processors The above method of detecting the fiber event point is performed.

The embodiment further provides a computer program product comprising a computer program stored on a non-transitory computer readable storage medium, the computer program comprising program instructions, when the program instructions are executed by a computer And causing the computer to perform any of the above methods of detecting an optical fiber event point.

The apparatus and method of the present disclosure can highlight the event points in discrete data points by wavelet operation and square calculation, and then reduce the detection time by detecting in multiple detection windows respectively, thereby solving the problem that the OTDR cannot be inspected for long-distance optical fibers. The problem of detecting or leaking the detection event point achieves the purpose of detecting the remote event point and effectively improves the detection accuracy.

DRAWINGS

1 is a schematic structural diagram of an apparatus for detecting an event point of an optical fiber in this embodiment;

2 is a data diagram of the device in the embodiment using wavelet calculation;

Figure 3 is a partial enlarged view of the distal end window of the wavelet after the embodiment;

4 is a flow chart of a method for detecting an optical fiber event point in this embodiment;

FIG. 5 is a schematic structural diagram of hardware of an electronic device according to this embodiment.

detailed description

In order to solve the problem that the OTDR cannot detect or miss the detection event point when performing inspection of the long-distance optical fiber, the present disclosure provides an apparatus and method for detecting an optical fiber event point, which are described below with reference to the drawings and implementation. For example, the present disclosure will be described. As shown in FIG. 1, an apparatus for detecting an optical fiber event point in this embodiment includes the following modules.

The wavelet calculation module 10 is configured to perform wavelet processing on the signal data of the backscattered light and the reflected light for detecting the optical pulse in the optical fiber, and then squared to obtain the squared data of the signal.

The window dividing module 20 is configured to divide the square data of the signal into n segments, and each segment corresponds to a detection window; wherein n is a natural number greater than 1.

The event point detection module 30 is configured to look up event points in a plurality of detection windows, respectively.

The detection principle of OTDR is to transmit narrow pulsed light with a certain repetition period and width into the fiber under test. When light is transmitted in the fiber, scattering phenomenon occurs, that is, scattered light in multiple directions is generated in the fiber. At the event point (geometric defect or fracture surface) of the fiber, the refractive index abrupt changes, and a part of the backward scattered light and reflected light can be transmitted back to the incident end along the fiber. By detecting the backscattered light and the reflected light of the optical fiber, the parameter characteristic distribution of the north side optical fiber line can be obtained according to the amplitude curve of the backward optical signal along the time axis.

Because the distance of the test fiber is far, the detection device receives the reflection of the remote event point, the scattering signal is very weak, and the problem of the detection or the leak detection is not caused. In this embodiment, the wavelet calculation module 10 performs the wavelet operation and the square calculation, and the discrete data is performed. The abnormal point (event point) is highlighted in the point, and then the window (detection window) detection is performed by the event point detecting module, which shortens the detection time and solves the problem that the OTDR cannot detect or miss the detection event point when performing long-distance fiber inspection. The purpose of detecting the remote event point is achieved, and the detection precision is effectively improved.

On the basis of the above-described embodiments, the modified embodiments of the above-described embodiments can be proposed, and only the differences from the above-described embodiments will be described in the following modified embodiments.

Wherein the number of n is determined by the detection distance of the optical fiber. By setting the number of detection windows according to the detection distance, near and far window processing can be realized, and the detection precision can be improved.

In an embodiment of the embodiment, the event point detection module includes a plurality of sub-detection modules; wherein one of the sub-detection modules corresponds to one detection window.

Each sub-detection module is set to check threshold according to the corresponding detection window of the sub-detection module and the The relationship between the squared data of the signals in the detection window corresponding to the sub-detection module is used to find an event point in the detection window; wherein the check thresholds of the multiple detection windows are different from each other.

Because the detection distance is different, the loss of the backscattered light and the reflected light is also different. Therefore, in this embodiment, one sub-detection module is set for each detection window, and the check threshold in each detection module can be set according to the detection distance to improve Detection accuracy.

Optionally, each of the sub-detection modules may be configured to sort the square data of the signals in the detection window corresponding to the sub-detection module according to the largest to the smallest, and start from the maximum signal squared data, and select according to the ranking. A predetermined number of the squared data of the signal is averaged; the calculated average value is used as a check threshold; and the square of the signal in the detection window that is larger than the set threshold of the check threshold is used as the event point.

For example, in the present embodiment, wavelet operation and square operation are used, and after the feature points are enlarged, the window method can be used to solve problems such as undetectable or leak detection. The window size can be adjusted as required. The squared data is divided into multiple time windows (ie, detection windows), and its own processing is performed in the time window. Look for the "event point" in the window, the event point is satisfied: take the 10 largest data in the window to average, and use this average as the threshold of the window. If the data in the window is twice the average value, then It is the event point.

Optionally, the wavelet calculation module is configured to perform wavelet operation on the signal data of the backscattered light and the reflected light to obtain high frequency partial data after wavelet operation; and square the high frequency partial data Get the squared data of the signal.

In the present embodiment, the wavelet operation performs signal processing by convolution at the time of event point search, and determines the position of the event point by judging the abnormal point of the high frequency portion. In the present embodiment, high-frequency data is obtained from the wavelet operation result, and the high-frequency data is squared. Since only the wavelet high-frequency portion data is acquired, the calculation amount of the square operation is reduced, and thus the square operation of the high-frequency partial data is performed. The time consuming can be half of the wavelet full square operation.

In another embodiment of this embodiment, the apparatus further includes the following modules.

An optical pulse generation module configured to generate the detection light pulse using a Gray complementary sequence and to be incident Into the fiber. And a data sampling module configured to receive the backscattered light and the reflected light of the detected light pulse, and convert the received backscattered light and the reflected light optical signal into an electrical signal.

A voltage loss conversion module configured to convert the electrical signal into a loss.

And an operation module configured to calculate the loss of the conversion and the Gray complementary sequence to obtain signal data of the backscattered light and the reflected light.

Optionally, the optical pulse generating module is further configured to set the number of bits of the Gray complementary sequence according to the detection distance of the optical fiber.

The use of high-power light-emitting devices in the related art can also achieve the purpose of detecting remote event points of long-distance fibers, but high-power light-emitting devices are expensive. The present embodiment can achieve the same effect of using a high-power light-emitting device based on the Gray complementary sequence and the low-power light-emitting device, and thus can save cost.

Alternatively, a flexible variable Gray complementary sequence number of bits is used. The number of bits in the Gray complementary sequence is set based on the estimated length of the test fiber distance. For long-distance detection, the use of the Gray complementary sequence with a large number of bits can increase the accuracy of the distal test; for short-distance detection, the use of the Gray complementary sequence with a small number of bits can shorten the test time.

The detection flow of this embodiment will be briefly described below through an application example.

The device for detecting an optical fiber event point in this application example includes the following modules.

Optical pulse generation module, data sampling module, voltage loss conversion module, correlation operation module, wavelet calculation module, window division module and event point detection module.

The testing process includes the following steps.

In step 1, the pulse generator (ie, the optical pulse generation module) emits a narrow-pulse drive laser diode (LD) with adjustable width to generate a pulse of light of a desired width, which is incident on the fiber under test after passing through the directional coupler. .

和WK、

送入光纤，格雷互补序列生成如下。Wherein, OTDR using Golay complementary sequences, _K by the A, B _K generated four unipolar pulses U _K,

And WK,

Feed into the fiber, the Gray complementary sequence is generated as follows.

A _K =[a ₀ , a ₁ , ..., a _n-1 ];

B _k =[b ₀ , b ₁ , . . . , b _n-1 ];

A _K and B _K are a pair of Gray complementary sequences, and S1 and S2 are pairs of Gray complementary sequences after synthesis.

S1=A _K B _k =a ₀ , a ₁ , . . . , a _n-1 , b ₀ , b ₁ , . . . , b _n-1 ;

表示b_i的取补，即0变成1，1变成0。In the formula,

Represents the complement of b _i , that is, 0 becomes 1, and 1 becomes 0.

和W_k、

Where A _K and B _k respectively generate U _k ,

And W _k ,

U _k =β(1+A _k ), W _k =β(1+B _k );

In the formula, β is a bias constant, and different numbers can be taken according to actual conditions. If β=1/2 is set, then:

among them,

In step 2, the backscattered light and the Fresnel reflected light in the optical fiber enter the photodetector through the coupler, and the photodetector converts the received scattered light and the reflected optical signal into an electrical signal, which is amplified by the amplifier and sent to Sampling device (data sampling module).

In step 3, the sampling device converts the acquired sampled data into a loss.

In step 4, the arithmetic module performs arithmetic processing on the data.

即偶数次发生U_k，奇数次发生

第二次奇偶单次序列发送W_k和

即偶数次发送W_k，奇数次发送

In the Field Programmable Gata Array (FPGA), two parity single-sequence tests are performed respectively to test the Gray complementary sequence. For example, the first parity single sequence sends U _k and

That is, U _k occurs even times, and odd times occur.

The second parity single sequence sends W _k and

Even sending W _k even times, sending odd times

After the test, four sets of data are obtained, that is, the first set of unipolar pulses of the backscattered light and the reflected light signal and the second set of unipolar pulsed backscattered light are obtained by the first parity single sequence test. The reflected light signal, the second odd-even sequence test results in a third set of unipolar pulsed backscattered light and reflected light signals and a fourth set of unipolar pulsed backscattered and reflected light signals.

The backscattered light and the reflected light signal of the first and second sets of unipolar pulses are then subtracted to obtain detected data a _n . The backscattered light and the reflected light signal of the third and fourth sets of unipolar pulses are subtracted to obtain detected data _bn .

Correlate the first code of the detection data a _n and the Gray complementary sequence g1 _n+j to obtain c _j ; and perform a correlation operation on the second code of the detection data b _n and the Gray complementary sequence g2 _n+j to obtain d _j ; The correlation operation is as follows.

Where c _j and d _j represent correlation operation results, a _n and b _n represent detection data, and g1 _n+j and g2 _n+j represent Gray complementary sequences, respectively. N is the number of data, 0 ≤ n ≤ (N-1), 0 ≤ (n + j) ≤ Gray complementary sequence number, (-N + 1) ≤ j ≤ (N-1).

The two correlation operation results c _j and d _j are added to obtain correlated backscattered light and signal data of the reflected light.

In step 5, wavelet operation is performed on the data after the correlation operation, wherein FIG. 2 is a data map calculated by using wavelet; FIG. 3 is a partial enlarged view of the far-end window after wavelet calculation; the following is a remote event point found. the result of.

The noise is 0.005282 and the event point is 0.007231 (the noise is relatively large and very close to the event point).

Use only the wavelet threshold to find the event point and use the window to find the following event point.

The first event point, location: 20050, reflection intensity: 2.896377, loss: 0.024590, remarks: reflection event!

The second event point, location: 40097, reflection intensity: 5.021379, loss: 0.005900, remarks: reflection event!

The third event point, location: 60246, reflection intensity: 2.617850, loss: 0.012000, remarks: fiber optic remote!

It can be seen from the results of the remote event points found above that after small and wave processing, An abnormal point.

In step 6, the square is calculated by window to obtain event point information.

Optionally, the squared result is windowed, and the threshold in each window is averaged according to the 10 largest data in the window, and the value is used as a threshold in the window.

The threshold is calculated. If it is greater than 2 times the threshold in this window, it is considered as the event point.

The device of the embodiment can achieve the purpose of detecting the remote event point while shortening the detection time. Therefore, the solution provided by the embodiment can shorten the detection time and effectively reduce the problem of missed detection of the event caused by testing the long-distance fiber.

The use of high-power light-emitting devices can also achieve the purpose of detecting remote event points of long-distance fibers, but the high-power light-emitting devices are expensive, so the light pulse generating module of the present device uses low-power illumination under the premise of cost saving. The device can achieve the same effect with high power illuminators.

As shown in FIG. 4, a method for detecting an optical fiber event point in this embodiment is used for an optical time domain reflectometer, and the method includes the following steps.

In step 410, the signal data of the backscattered light and the reflected light of the detected optical pulse in the optical fiber are subjected to wavelet operation, and then squared to obtain signal squared data.

In step 420, the signal squared data is divided into n segments, and each segment corresponds to a detection window; wherein n is a natural number greater than 1.

In step 430, event points are looked up in a plurality of said detection windows, respectively.

Optionally, the searching for an event point in the plurality of the detection windows respectively includes the following steps.

In each of the detection windows, searching for an event point in the detection window according to a relationship between an inspection threshold of the detection window and a squared data of the signal in the detection window; wherein, the detection thresholds of the plurality of detection windows are not mutually the same.

Optionally, searching for the event point in the detection window according to the relationship between the check threshold of the detection window and the square data of the signal in the detection window includes the following steps.

The squared data of the signals in the detection window are sorted from largest to smallest, and the maximum signal squared data is used, and the set number of signal squared data is selected according to the sorting to perform an average calculation.

The calculated average value is taken as the inspection threshold.

The signal squared data in the detection window that is larger than the set threshold of the inspection threshold is used as the event point.

Optionally, before performing the wavelet operation on the signal data of the backscattered light and the reflected light for detecting the optical pulse in the optical fiber, the following steps are further included.

The detection light pulse is generated using a Golay complementary sequence and incident on the fiber.

Receiving the backscattered light and the reflected light of the detection light pulse, and converting the received backscattered light and the reflected light optical signal into an electrical signal.

The electrical signal is converted into a loss, and the loss is computed with the Gray complementary sequence to obtain signal data of the backscattered light and the reflected light.

Optionally, the method further comprises the following steps.

The number of bits of the Gray complementary sequence is set according to the detection distance of the optical fiber.

Optionally, after performing wavelet processing on the signal data of the backscattered light and the reflected light of the detected optical pulse in the optical fiber, performing squared to obtain the squared data of the signal, including the following steps.

Performing a wavelet operation on the backscattered light of the detection light pulse and the signal data of the reflected light in the optical fiber to obtain high frequency partial data after wavelet operation;

The high frequency portion data is squared to obtain signal squared data.

In the implementation of the method embodiment, reference may be made to the device embodiment described above. The method embodiment provides a method for detecting a long-distance fiber event point in an OTDR design, where the calculated data is a discrete point, and the discrete The data points are wavelet processed to highlight the abnormal points. Then use the window method to process the window from near to far. It is effective to solve the long-distance fiber detection for OTDR. Because the distance of the test fiber is far, the reflection and scattering signals received by the detection device at the far-end event point are very weak, which makes it impossible to detect. Or leak detection and other issues.

The embodiment further provides a computer readable storage medium storing computer executable instructions for performing the above method.

FIG. 5 is a schematic structural diagram of hardware of an electronic device according to the embodiment, as shown in FIG. 5, The electronic device includes one or more processors 510 and a memory 520. One processor 510 is taken as an example in FIG.

The electronic device may further include: an input device 530 and an output device 540.

The processor 510, the memory 520, the input device 530, and the output device 540 in the electronic device may be connected by a bus or other means, and the bus connection is taken as an example in FIG.

The input device 530 can receive input numeric or character information, and the output device 540 can include a display device such as a display screen.

The memory 520 is a computer readable storage medium that can be used to store software programs, computer executable programs, and modules. The processor 510 executes various functional applications and data processing by executing software programs, instructions, and modules stored in the memory 520 to implement any of the above embodiments.

The memory 520 may include a storage program area and an storage data area, wherein the storage program area may store an operating system, an application required for at least one function; the storage data area may store data created according to usage of the electronic device, and the like. In addition, the memory may include volatile memory such as random access memory (RAM), and may also include non-volatile memory such as at least one magnetic disk storage device, flash memory device, or other non-transitory solid state storage device.

Memory 520 can be a non-transitory computer storage medium or a transitory computer storage medium. The non-transitory computer storage medium, such as at least one magnetic disk storage device, flash memory device, or other non-volatile solid state storage device. In some embodiments, memory 520 can optionally include memory remotely located relative to processor 510, which can be connected to the electronic device over a network. Examples of the above networks may include the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

Input device 530 can be configured to receive input numeric or character information and to generate key signal inputs related to user settings and function control of the electronic device. The output device 540 can include a display device such as a display screen.

The electronic device of the present embodiment may further include a communication device 550 that transmits and/or receives information over a communication network.

A person skilled in the art can understand that all or part of the process of implementing the above embodiment method can be completed by executing related hardware by a computer program, and the program can be stored in a non-transitory computer readable storage medium. The program, when executed, may include the flow of an embodiment of the method as described above, wherein the non-transitory computer readable storage medium may be a magnetic disk, an optical disk, a read only memory (ROM), or a random access memory (RAM). Wait.

Industrial applicability

The apparatus and method for detecting an optical fiber event point provided by the present disclosure highlights an event point in discrete data points by wavelet operation and square calculation, and then respectively reduces detection time by detecting in multiple detection windows, thereby solving the problem that the OTDR is long. When the optical fiber is inspected, the problem of detecting the event point cannot be detected or leaked, and the purpose of detecting the remote event point is achieved, and the detection precision is effectively improved.

Claims (13)

A device for detecting a fiber event point, comprising: The wavelet calculation module is configured to perform wavelet operation on the signal data of the backscattered light and the reflected light of the detected optical pulse in the optical fiber, and then squared to obtain the squared data of the signal; a window dividing module, configured to divide the square data of the signal into n segments, each segment corresponding to setting a detection window; wherein n is a natural number greater than 1; The event point detection module is configured to search for event points in a plurality of the detection windows, respectively. The device of claim 1 , wherein the event point detection module comprises a plurality of sub-detection modules, wherein one of the sub-detection modules corresponds to one of the detection windows; Each of the sub-detection modules is configured to search for the relationship between the check threshold of the detection window corresponding to the sub-detection module and the squared data of the signal in the detection window corresponding to the sub-detection module. The event point; wherein the check thresholds of the plurality of detection windows are different from each other. The apparatus according to claim 2, wherein each of said sub-detection modules is arranged to sort the squared data of signals in the detection window corresponding to said sub-detection module from largest to smallest, and from the largest signal squared data. Starting, selecting a set number of the signal squared data according to the sorting to perform an average calculation; Using the calculated average value as the check threshold of the detection window corresponding to the sub-detection module; The signal squared data in the detection window corresponding to the sub-detection module that is larger than the set threshold of the check threshold is used as the event point. The apparatus of any one of claims 1 to 3, further comprising: An optical pulse generation module configured to generate the detection light pulse using a Gray complementary sequence and incident on the optical fiber; a data sampling module configured to receive the backscattered light and the reflected light of the detection light pulse, and convert the received backscattered light and the reflected light optical signal into an electrical signal; a voltage loss conversion module configured to convert the electrical signal into a loss; An arithmetic module configured to calculate the loss and the Gray complementary sequence to obtain the The signal data of the scattered light and the reflected light. The apparatus of claim 4 wherein said optical pulse generating module is further configured to set a number of bits of said Golay complementary sequence based on a detected distance of said optical fiber. The apparatus according to any one of claims 1 to 3, wherein the wavelet calculation module is configured to perform wavelet operation on signal data of the backscattered light and the reflected light to obtain a wavelet operation High frequency part data; The high frequency portion data is squared to obtain signal squared data. A method of detecting an optical fiber event point, comprising: Performing a wavelet operation on the signal data of the backscattered light and the reflected light of the detected optical pulse in the optical fiber, and performing squared to obtain the squared data of the signal; Dividing the signal squared data into n segments, each segment correspondingly setting a detection window; wherein n is a natural number greater than 1; Find event points in a plurality of said detection windows, respectively. The method of claim 7, wherein the finding the event points in the plurality of the detection windows respectively comprises: In each of the detection windows, searching for an event point in the detection window according to a relationship between a check threshold of the detection window and the squared data of the signal in the detection window; wherein, the plurality of The check thresholds of the detection windows are different from each other. The method of claim 8, wherein the finding an event point in the detection window according to a relationship between an inspection threshold of the detection window and the squared data of the signal in the detection window comprises: Aligning the squared data of the signals in the detection window according to the largest to the smallest, and starting from the maximum signal squared data, selecting a set number of signal squared data according to the sorting to perform an average calculation; Using the calculated average value as the inspection threshold; The signal squared data in the detection window that is larger than the set threshold of the inspection threshold is used as the event point. The method according to any one of claims 7-9, wherein before the wavelet operation of the signal data of the backscattered light and the reflected light for detecting the optical pulse in the optical fiber, the method further comprises: Generating the detection light pulse using a Gray complementary sequence and incident on the optical fiber; Receiving the backscattered light and the reflected light of the detecting light pulse, and converting the received backscattered light and the reflected light optical signal into an electrical signal; The electrical signal is converted into a loss, and the loss is computed with the Gray complementary sequence to obtain signal data of the backscattered light and the reflected light. The method of claim 10 further comprising: The number of bits of the Gray complementary sequence is set according to the detection distance of the optical fiber. The method according to any one of claims 7 to 9, wherein the wavelet data of the backscattered light and the reflected light of the detected optical pulse in the optical fiber are subjected to wavelet operation, and squared to obtain signal squared data, including: Performing a wavelet operation on the backscattered light of the detection light pulse and the signal data of the reflected light in the optical fiber to obtain high frequency partial data after wavelet operation; The high frequency portion data is squared to obtain signal squared data. A computer readable storage medium storing computer executable instructions for performing the method of any of claims 7-12.

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