KR20050074053A - Otdr system and method for detecting positions of multiple landslides - Google Patents

Abstract

The present invention relates to an OTR measurement system for detecting a landslide occurrence position that can effectively detect signs occurring during landslide occurrence and slope collapse using an optical fiber cable. For this purpose, a landslide occurrence position OTR measurement system according to the present invention comprises: pulse generating means for generating an electric pulse signal having a predetermined pulse period and pulse width; A laser diode for outputting pulsed light according to the electrical pulse signal generated by the pulse generating means; Coupling means for coupling strong pulsed light to the optical fiber at the pulse period in the laser diode and outputting pulsed light scattered backward by the characteristics of the optical fiber; A photo detector for measuring the optical power of pulsed light from the coupling means and converting the measured optical power into an electrical signal; An amplifier for amplifying the electrical signal output from the photo detector; An AD converter having two input / output channels and converting the electrical signal amplified by the amplifier into a digital signal within a sampling rate of up to 300 MHz; While storing the digital signals received through the two input and output channels of the AD converter, averaging the digital signals and analyzing the signals to output the analysis data to an external display, the pulse width and the pulse period in accordance with the analysis data And a signal processor for outputting a control signal for adjusting and a setting signal for adjusting the sampling rate.

Description

OTDR system and method for detecting the occurrence of landslides OTDR system and method for detecting the location of landslides

The present invention relates to an OTR measurement system for detecting a landslide occurrence position. In particular, a landslide occurrence position detection OTRD system capable of minimizing a natural disaster by detecting the occurrence of landslides in advance quickly and accurately by using an advanced fiber optic sensor. It relates to a measurement system.

Techniques for measuring landslides using fiber optics are still in the early stages of technological development worldwide. There are several optical fiber sensors currently used, and representative examples include fiber bragg grating (FRB) sensors, distributed fiber optic sensors, and macro distortion monitor (MDM) systems. The distributed optical fiber sensors include Rayleigh scattering OTDR (common OTDR), Brillouin scattering OTDR (BOTDR), and Raman scattering OTDR (ROTDR).

In general, this optical time domain reflectometry (OTR) method has been widely applied in the field of structural measurement since it was first reported in 1976. The main application of this OTR system is to find defects in the fiber optic communication network or to monitor the attenuation of the propagation light. The ODT method uses backscattering of light incident from the pulsed light source into the optical fiber. Light propagating through the fiber causes Rayleigh scattering due to the slight variation in the fiber core refractive index. In addition, light reflection occurs at discontinuous points, connections, and breaks in the optical fiber. The output P (z) of the backscattered light in the OTR system is described as in Equation 1 below with respect to the position z at which the scattering occurs in the optical fiber.

[Equation 1]

In Equation 1, S (z) is the ratio of backscattered scattered light, and α _s (z) is the attenuation coefficient of the optical fiber. In addition, V _g is the group velocity of light and α _f and α _b are the attenuation coefficients in the front and rear directions of the optical fiber, respectively, and have the same value (α _f = α _b = α). The reflection position z of light has a relationship of z = tV _g when the arrival time after the start of the signal is 2t.

On the other hand, the output of the backscattered light detected when the attenuation coefficient and the backscattering ratio are constant is expressed in the form of an exponential function with time as shown in Equation 2 below.

[Equation 2]

Here, when the state of the optical fiber is constant, A ₁ and B ₁ are constant values.

This OTR system can detect a change in the attenuation coefficient α when the scattering coefficient α _s and the backscattering ratio s are constant. The output of backscattered light detected under these conditions is as shown in Equation 3 below.

[Equation 3]

In Equation 3 above, A ₂ is a constant.

Meanwhile, the rate of change of the detection signal is proportional to the attenuation coefficient. Alternatively, when α and S are constant, the change in α _s may be confirmed as in Equation 4.

[Equation 4]

Strictly, the value of α generally changes with respect to α _s . If the integral value inside the exponential function in Equation 4 is small, the error is reduced.

Incremental optical fiber bending of several centimeters results in less light attenuation, but microscopic bending, such as bending or bending in very small areas, produces significant light loss in both single-mode and multi-mode fiber. The micro bending loss in single mode fiber is theoretically solved by calculating the energy loss in the main mode. Therefore, simply measuring the light attenuation amount of the single mode optical fiber can quantitatively determine the bending deformation shape. On the other hand, multimode fiber is difficult to know its bending loss behavior.

Until now, most of the slopes have no special safety measures, or even if there are safety measures, drainage, retaining walls, or rockfalls are prevented on artificial incisions, embankments, or slopes of landslides where there is a high risk of landslides. Only small scale safety measures such as wire mesh are used.

However, such safeguards against landslides or rocks are not appropriate safeguards in Korea, where 70% of the land is mountainous and large landslides occur annually due to heavy rainfall such as the rainy season. In addition, even with the above safety measures, the optimal installation location or installation method is not defined in consideration of the characteristics or cracks of the inclined ground or underground rock on the inclined ground, and is determined appropriately by the practical experience of the contractor. Due to the improper or arbitrary installation of the installation location, the human and material damage still occurs because of this, and even the safety measures, once constructed, cannot respond to changes in time or the surrounding environment. There is a problem in that safety measures should be taken according to the characteristics of the second and third slopes. On the other hand, since the crack of the rock is started at very fine intervals and the speed of its progress is slow, it is difficult to predict the degree of crack and the speed of its growth during construction and to establish safety measures accordingly.

In order to solve the above problems, the present invention is installed in a place where there is a high risk of landslides, and in order to minimize natural disasters caused by heavy rains or earthquakes, a specific landslide occurrence sign or a collapse sign of a slope, a large scale It is an object of the present invention to provide an OTR measurement system for landslide occurrence position detection that can accurately detect a landslide occurrence position as well as its occurrence position in advance.

In order to achieve the above object, the landslide occurrence position OTR measurement system according to the present invention comprises: pulse generating means for generating an electric pulse signal having a predetermined pulse period and pulse width in accordance with a control signal; A laser diode for outputting high output pulsed light according to the electrical pulse signal generated by the pulse generating means; Coupling means for coupling the strong pulsed light output from the laser diode in the pulse period to an optical fiber, and outputting pulsed light scattered backward by the characteristics of the optical fiber; A photo detector for measuring the optical power of the backscattered pulsed light input from the coupling means and converting the measured optical power into an electrical signal; An amplifier for amplifying the electrical signal output from the photo detector; An AD converter having two input / output channels and converting the electrical signal amplified by the amplifier into a digital signal at a sampling rate of up to 300 MHz according to a predetermined set signal; While storing the digital signal received through the two input and output channels of the AD converter, and performing the averaging of the digital signal from the channel and the analysis of the signal to output the analysis data to the external display, the pulse width in accordance with the analysis data And a signal processor for outputting a control signal for adjusting a pulse period to the pulse generator and outputting a setting signal for adjusting a sampling rate to the AD converter.

By including the above configuration, the present invention can provide an effect of improving the sampling rate of the digital signal to accurately identify the occurrence of landslides in advance. In addition, the present invention can measure the displacement of several points at the same time by using an advanced optical fiber, it is possible to grasp the signs of landslides more widely. Even in the absence of landslides, long-term assessments of the behavior of landslides in a particular region can be made, as well as the geological characteristics of the area, and can be recorded and stored in real time for future geological surveys.

Further, according to the present invention, the optical fiber is formed in a plurality of spiral shapes to more accurately detect the landslide occurrence position in a region where landslides are likely to occur.

By further including the above configuration, by making the shape of the optical fiber into a plurality of spiral shapes, the displacement state of the inclined surface can be detected more precisely.

Meanwhile, in the configuration of the present invention, the present invention further includes an interleaver for interleaving the digital electrical signal in a signal processing unit, and the interleaver may provide the same resolution as that corresponding to sampling of up to 2 GHz in real time.

In the configuration of the present invention, the system further comprises a plurality of speakers connected to the output of the signal processing unit for receiving an alarm signal from the signal processing unit to generate an alarm sound for notifying that a landslide occurs, and the signal If the processing unit determines that a slight landslide will occur according to the digital signal processing result, the processing unit outputs an alarm signal indicating the occurrence of a minor landslide to the manager's display and simultaneously generates an alarm sound to the speaker of the manager. In addition, if it is determined that the optical fiber is cut based on the processing result of the digital signal, an alarm signal is displayed on the manager's display and the alarm sound is displayed on the manager's speaker to promptly notify the manager and the surrounding area where the fiber is buried. At the same time It also generates alarm sound for multiple speakers in the area where the fiber is buried.

According to this configuration, the present invention can effectively enforce traffic hazard warning, prohibition of resident traffic, control of road traffic, or evacuation of local residents to the area based on the signs of landslides in real time. Alarms can be triggered through loudspeakers buried around the landslides, enabling prompt response to property and casualty damages, as well as effective warning of landslides to neighboring passers-by.

A method for detecting the occurrence position of a landslide according to the present invention comprises the steps of: generating an electrical pulse signal having a predetermined pulse period and pulse width according to a control signal; Outputting high power pulsed light according to the electric pulse signal generated in the electric pulse signal generating step; Coupling strong pulsed light output in the pulse period in the pulsed light output step to an optical fiber, and outputting pulsed light scattered backward by the characteristics of the optical fiber; Measuring the optical power of the backscattered pulsed light input from the optical fiber and converting the measured optical power into an electrical signal; Amplifying the AD converted electrical signal; Converting the amplified electrical signal into a digital signal in a range of up to 300 MHz according to a set signal through two input / output channels; While storing the digital signals received through the two input and output channels, averaging the digital signals from the channels and analyzing the signals to output the analysis data to an external display, the pulse width and the pulse period in accordance with the analysis data And a signal processing step of outputting a control signal for adjusting the signal to the pulse generating means, and outputting a setting signal for adjusting the sampling rate to the AD converter, by which the configuration can provide the same effects as in claim 1. have.

In the signal processing step in the configuration of the present invention, if it is determined that a slight landslide, such as the runoff of soil, will occur according to the processing result of the digital signal, the manager may notify an administrator of an alarm signal indicating the occurrence of a slight landslide. When a graph is output to the display 180 and an alarm sound is generated to the manager speaker 190 and it is determined that the optical fiber has been cut based on the processing result of the digital signal, the risk of a large landslide such as falling of a rock can be quickly obtained. In order to notify not only the manager but also the surrounding area where the optical fiber is buried, an alarm signal indicating that a large landslide occurs is displayed on the manager's display 180 and outputs an alarm sound to the manager speaker 190 while installing the nearby optical fiber. Generating an alarm sound to the plurality of speakers 192 as well. It said, whereby it is possible to provide a fourth term effect.

(Example)

Hereinafter, the most preferred embodiments of the present invention will be described with reference to the accompanying drawings so that those skilled in the art can easily implement the technical idea of the present invention. .

1 is a block diagram showing an OTR measurement system for detecting a landslide occurrence position according to an embodiment of the present invention. The ODT measurement system measures the physical state of the optical fiber by outputting light pulses having a predetermined period and width, and then measuring the time and intensity at which the light pulses return. The OTR measurement system for landslide occurrence position detection according to the present invention includes a pulse generating means (110), a laser diode (120), a coupling means (130), a photodetector (140), and an amplifier. 150, an analog-to-digital converter 160, and a signal processor 170.

Here, the pulse generating means 110 generates an electric pulse signal having a predetermined pulse period and pulse width according to the control signal from the signal processing unit 170 and outputs it to the laser diode 120. The pulse generating means 110 produces a pulse waveform necessary for outputting pulsed light from the pump-LD of the laser diode 120. In addition, the pulse generator 110 may provide a function of controlling the output electric pulse signal to have an appropriate pulse period and pulse width according to the environment of the length of the optical fiber to be measured, the amount of attenuation of the bending of the optical fiber, and the bending occurrence position. do. Pulse generating means having this function is shown in FIG.

Referring to FIG. 2, a block diagram schematically showing a pulse generating means 110 mounted in an OTR measurement system for detecting a landslide occurrence position according to an embodiment of the present invention is a first deep switch 202. , The second dips 204 and the controller 206.

The first dips 202 mounted in the pulse generating means 110 adjust the pulse width according to the position input in response to the control signal of the signal processing unit 170. Here, the first dips 202 preferably have an input value of 16 bits (0 to 215).

The second dips 204 mounted in the pulse generating means 110 adjust the pulse period according to the position input in response to the control signal of the signal processing unit 170. Here, the second dips 204 preferably have an input value of 16 bits (0 to 215).

The control unit 206 mounted in the pulse generating means 110 is designed by applying a field programmable gate array (FPGA), for example, implemented as an Altera EPF 10K40RC208-4 chip and used as a CPU of the pulse generating means. In response to the control signal of the signal processor 170, the electric pulse signal having a predetermined pulse width and pulse period and a trigger signal for synchronizing to inform the timing point of generating the pulsed light are output.

The pulse period and pulse width of the output pulse signal are determined by the input values of these dips 202 and 204 and the operating speed of the clock. For example, the pulse period is about 20 ms to 1.6 ms and the pulse width is about 10 ms. It has a range of ~ 20㎲. In one embodiment, the FPGA may be programmed as shown in Table 1 below using a VHSIC hardware description language (VHDL) programming language.

TABLE 1

According to the above program, the output waveform according to the input period and pulse width is shown in Table 2 as an example.

TABLE 2

On the other hand, the laser diode 120 receiving the pulse signal from the pulse generating means 110 is strong pulsed light to the coupling means 130 in accordance with the electrical pulse signal in accordance with the trigger signal output from the pulse generating means 110. Function to generate Here, in the ODT device of the present invention, preferably, a pump type laser diode (Pump-LD) having a large optical power may be used as a light source of the laser diode 120, and the center wavelength of the pulsed light generated by the pump type laser diode Has a line width of about 15 nm at 1464 nm and -10 Hz. Table 3 shows an example of the measurement results when the signal is not modulated with a pulse signal.

TABLE 3

Meanwhile, the coupling means 130 couples the strong pulsed light periodically output from the laser diode 120 from the optical coupling part 1232 to the optical fiber, and splicing and bending the optical fiber while the pulsed light proceeds. It outputs the pulsed light scattered back according to the characteristics of the optical fiber, such as cutting, tension, compression, etc. to the photo detector 140. This coupling means 130 is coupled with the optical fiber 136 via the optical connector 134.

On the other hand, the optical fiber 136 connected to the coupling means 130 is buried in an area where there is a risk of landslides, so that the slopes of the buried areas are collapsed, large-scale landslides occur, rockfall or soil loss. Subject to bending, cutting, tensioning, or compression. At this time, the pulsed light propagating through the optical fiber 136 causes Rayleigh scattering in the region, partly lost and partly reflected. According to one embodiment, when the optical fiber 136 is buried so as to have a curved shape having a curvature of diameter phi as shown in FIG. 3, since the amount of light lost to the optical fiber outside of the pulsed light that is traveling inside occurs largely, By detecting the change in the amount of light, it is possible to accurately detect the minute displacement of the inclined surface. The relationship between the diameter phi and the amount of light attenuation that appears at this time is shown in FIG. 4. Therefore, as can be seen in Figure 4, by measuring the amount of light attenuation it is possible to accurately measure the degree of displacement with respect to the fiber-shaped optical fiber.

Referring now to FIG. 1, the attenuated pulsed light scattered back from the optical fiber 136 as described above is input to the photo detector 140 via the optical coupling means 130. Here, the photo detector 140 measures the optical power of the optical signal input from the coupling means 130, converts the measured optical power into an electrical signal and outputs it to the amplifier 150.

Meanwhile, the amplifier 150 amplifies the analog electric signal input from the photo detector 140 and outputs the amplified analog signal to the analog to digital (AD) converter 160.

In addition, the AD converter 160 converts the analog electrical signal input from the amplifier 150 into a digital signal according to the set signal of the signal processor 170 and outputs the digital signal to the signal processor 170. Here, the AD converter 160 may be designed using NI5911 PCI of National Instrument. The NI5911 board provides different quantization bits depending on the sampling rate, as shown in Table 4 below.

TABLE 4

In the exemplary embodiment of the present invention, the AD converter 160 has two input / output channels capable of sampling up to 300 MHz, and thus provides a resolution improved by three times the detection resolution of the measured real-time displacement compared to the conventional case, thereby providing finer displacement. In addition to effective detection, two input / output channels can be used to simultaneously detect multiple displacements at multiple points.

In general, the sampling rate is inversely proportional to the distance resolution. As the sampling rate is improved, the distance resolution is excellent. For example, at a 100 MHz sampling rate, the distance resolution is 1 m, at 300 MHz the distance resolution is 30 cm, and at 2 GHz the distance resolution is 5 cm. The amount of displacement of the optical fiber can also be detected more finely.

In addition, the present invention may include an interleaver 176 for interleaving the digital electrical signal in the signal processing unit 170, which provides the same resolution as that corresponding to 2 GB of sampling using an interleaving technique in the interleaver. can do.

In addition, the AD converter takes the form of a PCI card to enable smooth data communication with a PC computer, that is, the signal processor 170.

On the other hand, the signal processing unit 170, the signal processing unit 170, includes a data acquisition unit 171 and the operation processing unit 172, at the same time to store the digital data received from the AD converter 160 The digital processing unit 172 converts the digital data into a function of averaging the digital data, a trigger function, and a voltage scale in the form of voltage, and as a result, outputs the data to the external display 180 and generates the pulse. It serves to output the control signal to the means (110).

In addition, the signal processor 170 acquires data from the AD converter 160 using a graphical programming language (GPL), and initializes the AD converter, an input voltage range, a sampling rate, and a record length. Outputs a setting signal for setting?) To the ADC 160.

The signal processor 170 preferably outputs an analysis result as a graph, and may display the result value in the form of a voltage with respect to the received optical signal in a dB scale. For this purpose, the signal processor 170 may be implemented using LabVIEW 6i of National Instrument. For example, an example of the result is shown in Table 5 below.

TABLE 5

Looking at Table 5 above, it can be seen that the voltage ㏈ scale of the back scattered pulsed light according to the distance of the optical fiber. Here, the part that forms a positive peak is a lot of backscattering, and is typically an optical connector part, an optical fiber splicing part, a crack generating part, and an optical fiber end part, and a part where the shock scale of pulsed light is greatly reduced is a part where a transmission loss occurs. Representatively, it appears in the bending part, the crack part, the cutting part, etc. of an optical fiber. Here, the backscattering occurring at the optical connector portion, the optical fiber splicing portion, or the optical fiber end can be easily identified in Table 5 by the detected time and distance. In Table 5, the variation of the backscattered optical beam scale generated in the optical fiber embedded in a specific area can be accurately detected to detect the physical change in the optical fiber.

For example, if an embedded fiber is subjected to physical changes such as bending, cracking, or cutting due to landslides or displacement of slopes, it will cause a large drop in the voltage ㏈ scale of the new backscattered pulsed light. Where the fiber is buried, soil runoff or some rock falls can cause the fiber to bend, with large drops in the voltage scale. On the other hand, in the case where the massive rock falls or a large landslide occurs in the place where the optical fiber is buried, the embedded optical fiber may be cut. In this case, since the pulsed light is mostly lost through the cut portion, the voltage drop of the detected light may be reduced. Will appear very large. An example is shown in Table 6 below.

TABLE 6

In the above case, when a load of about 3kg is applied to the optical fiber cable, it can be seen that the cut. In the abnormal region where the detected voltage drop is large, it may be determined that the optical fiber has been cut, and in this case, it is determined that the rock falls or a large landslide occurs. Therefore, if the alarm is triggered before the fiber cable is cut, the disaster can be prevented in advance.

Specifically, when such a landslide occurs, the system 100 is connected to the output of the signal processing section to receive an alarm signal of the signal processing section to alert the manager and to promptly notify the administrator that a landslide is occurring. The apparatus may further include a plurality of speakers 190 and 192 for generating sound. More specifically, the signal processing unit 170, in Table 5 and Table 6, when it is determined that a slight landslide, such as the runoff of soil in accordance with the processing result of the digital signal, an alarm signal indicating the occurrence of a slight landslide In order to notify the manager of the graph display on the manager's display 180 and at the same time can generate an alarm sound to the manager speaker 190, and if it is determined that the optical fiber is cut based on the processing result of the digital signal, The alarm signal is displayed on the manager's display 180 to promptly notify the manager as well as the manager of the large landslides, such as a fall, in the surrounding area where the fiber is buried. It also performs a function of generating an alarm sound to the plurality of speakers 192 installed in the vicinity.

The operation of the ODT measurement system for detecting a landslide occurrence position of the present invention described above is as follows.

First, when the pulse generating means 110 outputs a pulse signal to the laser diode 120, the laser diode 120 outputs pulsed light to the optical fiber in the coupling means 130. At this time, when the optical fiber is physically disturbed due to the occurrence of landslides or the like due to external factors, each mode of light transitions to another mode, and the distribution of optical power between the modes is changed. In addition, the physically disturbed light is reflected back or transmitted forward, and the back scattered pulsed light is returned along the optical fiber. At this time, the coupling means 130 outputs the returned optical power to the photo detector 140. The back scattered and output optical power is converted into an electrical signal by the photo detector 140 and the amplifier 150, amplified, and input to the AD converter 160. Thereafter, the AD converter 160 converts the signal amplified through the two input / output channels into a digital signal at a sampling rate of up to 300 MHz, and then the signal processor 170 converts the converted digital data into the display 180. For example, when the output is displayed as a graph or an urgent landslide such as an optical fiber is cut, an alarm signal directly indicating that the landslide has occurred is transmitted to the plurality of speakers 190 and 192, wherein the plurality of speakers 192 are managers. And alarms to people who pass around the landslide occurrence.

As a result, the present invention can effectively carry out warning of traffic hazards to the area, prohibition of resident traffic, control of road traffic, or evacuation of local residents based on the signs of landslides occurring in real time. Alerts can be issued through local loudspeakers to quickly respond to property disasters and casualties, and can effectively warn neighboring pedestrians of the risk of landslides.

As described above, the OTR measurement system for landslide occurrence detection has been described as an example according to the present invention, but the present invention is within the scope not departing from the technical idea of the present invention for those skilled in the art. Since various substitutions, modifications, and changes may be made within the scope of the present invention, it is not limited to the above-described embodiments and the accompanying drawings.

As described above, the present invention uses an advanced optical fiber and by using two input and output channels at 300MHz sampling, it is possible to improve the sampling rate of the digital signal to accurately identify the occurrence of landslides in advance, and at various points. Since the displacement of can be measured simultaneously, signs of landslides can be identified more extensively. The present invention can detect the displacement state of the inclined surface more precisely by making the shape of the optical fiber in the area of the risk of landslides, and in case of emergency, landslides in real time by making alarm sound through a plurality of speakers. According to the signs of occurrence, warning of traffic hazards in this area, prohibition of pedestrian traffic, control of road traffic, or evacuation of local residents can be implemented selectively, which can minimize the damage to property and life. At the same time, there is an advantage that the user can conveniently use the automated analysis in real time using a PCI card.

1 is a block diagram showing an OTR measurement system for detecting a landslide occurrence position according to an embodiment of the present invention;

FIG. 2 is a block diagram showing pulse generating means mounted to an OTR measurement system for detecting a landslide occurrence position according to an embodiment of the present invention; FIG.

FIG. 3 is a diagram illustrating a spiral optical fiber embedded in an inclined surface, which is used in conjunction with an OTR measurement system for detecting a landslide occurrence position according to an embodiment of the present invention. FIG.

FIG. 4 is a graph showing the backscattered light amount attenuation rate with respect to the diameter of the logical optical fiber shown in FIG. 3; FIG.

<Description of the reference numerals for the main parts of the drawings>

110: pulse generating means 120: laser diode

130 coupling means 140 light detector

150: amplifier 160: AD converter

170: signal processing unit

Claims (8)

A system for detecting a location of occurrence of a landslide, Pulse generating means (110) for generating an electrical pulse signal having a predetermined pulse period and pulse width in accordance with the control signal; A laser diode (120) for outputting high output pulsed light according to the electrical pulse signal generated by the pulse generating means (110); Coupling means (130) for coupling the strong pulsed light output from the laser diode (120) in the pulse period to an optical fiber and outputting pulsed light scattered backward by the characteristics of the optical fiber; A photo detector (140) for measuring the optical power of the backscattered pulsed light input from the coupling means (130) and converting the measured optical power into an electrical signal; An amplifier (150) for amplifying the electrical signal output from the photo detector (140); An AD converter (160) having two input / output channels and converting the electric signal amplified by the amplifier (150) into a digital signal at a sampling rate of up to 300 MHz according to a predetermined set signal; While storing the digital signal received through the two input and output channels of the AD converter 160, and averaging the digital signal from the channel and analyzing the signal to output the analysis data to the external display 180, And a signal processor for outputting a control signal for adjusting a pulse width and a pulse period to the pulse generating means 110 and for outputting a setting signal for adjusting a sampling rate to the AD converter 160 according to analysis data. Characterized by System for detecting location of landslides. 2. The system of claim 1, wherein the optical fiber (132) is formed of a plurality of tree shapes (300) to detect the landslide occurrence position more precisely. 3. The system according to claim 1 or 2, further comprising an interleaver (176) for interleaving the electrical signal in the signal processor (170). According to claim 3, The system 100 is connected to the output of the signal processing unit of the plurality of speakers 190, which generates an alarm sound to notify that the landslide occurs by receiving the alarm signal of the signal processing unit 170, And 192). According to claim 4, wherein the signal processing unit 170, if it is determined that a slight landslide, such as runoff of the soil according to the processing result value of the digital signal, an alarm signal indicating the occurrence of a minor landslide, the display of the manager When outputting a graph to the 180 and generating an alarm sound to the speaker 190 of the manager and determining that the optical fiber has been cut based on the processing result of the digital signal, the risk of a large-scale landslide, such as a rock fall, can be quickly obtained. In order to notify not only the manager but also the surrounding area where the optical fiber is buried, an alarm signal indicating a large landslide occurs on the manager's display 180 and at the same time generates an alarm sound to the manager speaker 190, and also the surrounding area where the optical fiber is buried. The occurrence of an avalanche, characterized by generating an alarm sound to the plurality of speakers 192 provided. A system for detecting value. In the method for detecting the occurrence position of landslides, Generating an electrical pulse signal having a predetermined pulse period and a pulse width according to the control signal; Outputting high power pulsed light according to the electric pulse signal generated in the electric pulse signal generating step; Coupling strong pulsed light output in the pulse period in the pulsed light output step to an optical fiber, and outputting pulsed light scattered backward by the characteristics of the optical fiber; Measuring the optical power of the backscattered pulsed light input from the optical fiber and converting the measured optical power into an electrical signal; Amplifying the AD converted electrical signal; Converting the amplified electrical signal into a digital signal in a range of up to 300 MHz according to a set signal through two input / output channels; While storing the digital signals received through the two input and output channels, averaging the digital signals from the channels and analyzing the signals to output the analysis data to the external display 180, the pulse width in accordance with the analysis data And a signal processing step of outputting a control signal for adjusting a pulse period to the pulse generating means 110 and outputting a setting signal for adjusting a sampling rate to the AD converter. Method for detecting the location of a landslide. According to claim 6, The system 100 is connected to the output of the signal processing unit of the plurality of speakers 190, which generates an alarm sound to notify that the landslide occurs by receiving the alarm signal of the signal processing unit 170, And 192). 8. The method of claim 7, wherein in the signal processing step, when it is determined that a slight landslide, such as a runoff of soil, is generated according to the processing result of the digital signal, the manager is to notify the manager of an alarm signal indicating the occurrence of a slight landslide. In addition to outputting a graph on the display 180 and generating an alarm sound in the manager speaker 190 and determining that the optical fiber has been cut based on the processing result of the digital signal, the risk of a large landslide, such as a rock fall, is determined. In order to quickly notify not only the manager but also the surroundings of the optical fiber, an alarm signal indicating that a large landslide occurs is displayed on the manager's display 180 and an alarm sound is output to the manager speaker 190 while the optical fiber is buried nearby. It also generates an alarm sound to a plurality of speakers 192 installed It is a method for detecting the location of occurrence of a landslide.