CN111982170B - Track description method applied to optical fiber sensing system - Google Patents
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- CN111982170B CN111982170B CN202010877494.7A CN202010877494A CN111982170B CN 111982170 B CN111982170 B CN 111982170B CN 202010877494 A CN202010877494 A CN 202010877494A CN 111982170 B CN111982170 B CN 111982170B
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- G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
- G01D5/26—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
- G01D5/32—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light
- G01D5/34—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells
- G01D5/353—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells influencing the transmission properties of an optical fibre
- G01D5/35338—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells influencing the transmission properties of an optical fibre using other arrangements than interferometer arrangements
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Abstract
The application discloses a track description method applied to an optical fiber sensing system, which adopts an intensity-time algorithm to realize the track positioning of a disturbance source, and calculates the light intensity difference set in each time interval by obtaining Rayleigh backward scattering light emitted by the sensing optical fiber and obtaining corresponding Rayleigh backward scattering signals, and comparing each light intensity difference value in the light intensity difference value set with a preset disturbance difference threshold value, thereby determining the disturbance defense area, respectively drawing circles in a plane by taking the center points of the disturbance defense area and the adjacent front and rear disturbance defense areas as the center of the circle to obtain the common point of the three circles as a disturbance source, repeating the operation, and sequentially obtaining the position of the disturbance source in each time interval, and connecting the disturbance points in all the time intervals according to the acquisition time sequence to obtain the motion trail of the disturbance source, so that the motion trail of the disturbance source is accurately and quickly positioned.
Description
Technical Field
The application relates to the technical field of motion track description, in particular to a track description method applied to an optical fiber sensing system.
Background
With the increasing demand for security in smart cities, monitoring and protection of public facilities are becoming more important. In the traditional video monitoring, personnel watch a monitoring screen by naked eyes and judge an intrusion event through self experience. In the face of huge monitoring networks and massive data, detection personnel are easy to fatigue, and intrusion is caused to miss reports.
In addition, the intelligent video monitoring technology analyzes and monitors videos through a computer, and the problem of fatigue of personnel is solved. However, the intelligent video monitoring technology has the problem of difficult cross-camera identification, and is difficult to apply to scenes with high real-time requirements.
At present, the phi-OTDR distributed optical fiber sensing technology generates scattering coherent light intensity change through interference to obtain a disturbance position, the detection distance is long, the detection strain sensitivity can reach 5n epsilon, and multi-point detection can be realized. However, in the existing phase, the distributed optical fiber sensing technology of the phi-OTDR only locates the disturbance defense area, and lacks research on disturbance source location and trajectory description, so that the monitoring real-time performance is poor, and a supervisor can easily capture the disturbance source and miss the optimal opportunity.
Disclosure of Invention
The application provides a track description method applied to an optical fiber sensing system, which is used for solving the technical problems that the disturbance source is lack of positioning and track description in the existing optical fiber sensing system, and the monitoring instantaneity is poor.
In view of the above, the first aspect of the present application provides a trajectory description method applied to an optical fiber sensing system, where the applied optical fiber sensing system includes a laser, an acousto-optic modulator, an erbium-doped fiber amplifier, a data acquisition card, a photodetector, a circulator, a sensing fiber, a conducting fiber, and a computer; after the laser generates laser beams, the laser beams are modulated into optical pulses through the acousto-optic modulator, the optical pulses are subjected to power amplification through the erbium-doped fiber amplifier, the optical pulses are transmitted to the sensing fiber through the conducting fiber, Rayleigh backscattered light generated by the sensing fiber is received by the circulator and correspondingly Rayleigh backscattered light signals are output, the Rayleigh backscattered light signals are converted into Rayleigh backscattered electrical signals through the photoelectric detector, and the Rayleigh backscattered electrical signals are transmitted to the data acquisition card for analog-to-digital conversion and then transmitted to the computer for signal processing;
the signal processing comprises the following steps:
s1: reading the rayleigh backscatter signal;
s2: dividing the sensing optical fiber with the total length L into N equidistant intrusion prevention areas, wherein the length d of the intrusion prevention areas is [2nL/cTP]+1, where n is the refractive index of the optical fiber group, c is the vacuum speed of light, T is the duration of light pulse, L is the total length of the sensing optical fiber, p is the pulse width, and the intrusion prevention area is represented by D ═ D1，d2，……dN]；
S3: equally dividing the obtained Rayleigh backscattering signals into a plurality of time interval signal sets according to the acquisition time sequence of the data acquisition card, and expressing as F ═ F [ [ F [ ]1，F2，……FN]Wherein each of the time interval signal sets comprisesThe method comprises the steps that M frames of Rayleigh backscattering signals are obtained, each frame of Rayleigh backscattering signals is equally divided into N defense area Rayleigh backscattering signals corresponding to the intrusion defense area, the total light intensity value of the M frames of Rayleigh backscattering signals in each time period signal set is calculated, and the average light intensity value of each frame of Rayleigh backscattering signals in the time period signal set is calculated according to the total light intensity value of the M frames of Rayleigh backscattering signals in the time period signal set;
s4: subtracting the light intensity value of each defense area Rayleigh backscattering signal in the time interval signal set from the average light intensity value of each frame of the Rayleigh backscattering signal in the corresponding time interval signal set to obtain a light intensity difference, wherein the light intensity difference is represented as E1 ═ E1，e2，……ex]Repeating the steps to obtain the light intensity difference value set E ═ E in the period1，E2，……Ex]Repeating the operation to obtain light intensity difference value sets of N time periods;
s5: comparing each light intensity difference value in the light intensity difference value set of each time interval with a preset disturbance difference threshold value one by one, and judging that the intrusion prevention area corresponding to the light intensity difference value set of the time interval is a disturbance prevention area N with disturbance when the light intensity difference value exceeds the preset disturbance difference threshold valuexAnd executing steps S6-S7;
s6: obtaining the disturbance defense area NxCorresponding disturbance time and light intensity difference ExAnd obtaining adjacent disturbance defense areas N in front of and behind the disturbance defense areax-1And disturbance prevention area Nx+1Respectively corresponding light intensity difference Ex-1And Ex+1Obtaining the disturbance defense area N according to the negative correlation relationship between the light intensity difference at the disturbance source and the light intensity difference at the central point of the disturbance defense areaxThe disturbance prevention area Nx-1And the disturbance prevention area Nx+1Respectively corresponding radial distances r of optical fiber disturbance pointsx、rx-1And rx+1；
S7: on the same radial horizontal plane of the sensing optical fiber to disturb the defense area Nx、Nx-1And Nx+1Is taken as the center of a circleAnd respectively corresponding to the radial distance r of the disturbance point of the optical fiberx、rx-1And rx+1Drawing a circle for the radius, wherein the intersection point of the three circles which are intersected together is the disturbance source position HxAnd repeating the operation, sequentially obtaining the position of the disturbance source in each time interval according to the acquisition time sequence of the data acquisition card, and connecting the disturbance points in all the time intervals according to the acquisition time sequence to obtain the motion trail of the disturbance source.
Preferably, the step S5 specifically further includes:
and when the light intensity difference value is lower than the preset disturbance difference threshold value, judging that no disturbance action exists, and executing the steps S1-S5.
Preferably, the step S7 is followed by:
and establishing an electronic map corresponding to the intrusion prevention area, marking the intrusion prevention area in the electronic map, and correspondingly marking the motion trail of the disturbance source in the electronic map.
Preferably, the step S7 is followed by:
and judging the motion trend of the disturbance source according to the motion track of the disturbance source, and informing a monitoring person to start a preset video monitoring device in the disturbance defense area.
Preferably, the step S7 is followed by:
and judging the motion trend of the disturbance source according to the motion trail of the disturbance source, and sequentially starting water flowing lamps preset in the disturbance prevention area according to the judged motion trend of the disturbance source in a time sequence.
According to the technical scheme, the embodiment of the application has the following advantages:
the embodiment of the application provides a track description method applied to an optical fiber sensing system, which adopts an intensity-time algorithm to realize the track positioning of a disturbance source, and calculates the light intensity difference set in each time interval by obtaining Rayleigh backward scattering light emitted by the sensing optical fiber and obtaining corresponding Rayleigh backward scattering signals, and comparing each light intensity difference value in the light intensity difference value set with a preset disturbance difference threshold value, thereby determining the disturbance defense area, respectively drawing circles in a plane by taking the center points of the disturbance defense area and the adjacent front and rear disturbance defense areas as the center of the circle to obtain the common point of the three circles as a disturbance source, repeating the operation, and sequentially obtaining the position of the disturbance source in each time interval, and connecting the disturbance points in all the time intervals according to the acquisition time sequence to obtain the motion trail of the disturbance source, so that the motion trail of the disturbance source is accurately and quickly positioned.
Drawings
Fig. 1 is a schematic structural diagram of an optical fiber sensing system applied in a trajectory description method applied to the optical fiber sensing system according to an embodiment of the present application;
fig. 2 is a flowchart of a trajectory description method applied to an optical fiber sensing system according to an embodiment of the present application;
fig. 3 is a two-dimensional plane line graph in a trajectory description method applied to an optical fiber sensing system according to an embodiment of the present disclosure;
fig. 4 is a radial horizontal plane diagram of a sensing optical fiber in a trajectory description method applied to an optical fiber sensing system according to an embodiment of the present disclosure.
Detailed Description
In order to make the technical solutions of the present application better understood, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
Referring to fig. 1, the applied optical fiber sensing system includes a laser 1, an acousto-optic modulator 2, an erbium-doped fiber amplifier 3, a data acquisition card 7, a photodetector 9, a circulator 5, a sensing fiber 6, a conducting fiber 4, and a computer 8;
it is understood that the laser 1 may be a narrow linewidth laser, which can generate laser light with high coherence; the acousto-optic modulator 2 can modulate the laser into pulsed light; the erbium-doped fiber amplifier 3 is used for amplifying the power of the laser pulse so as to improve the Rayleigh backward scattering light intensity emitted by the sensing fiber 6, and the circulator 5 is used for receiving the Rayleigh backward scattering light emitted by the sensing fiber 6 and transmitting the Rayleigh backward scattering light to the data acquisition card 7; the specific working process is that after the laser 1 generates laser beams, the laser beams are modulated into optical pulses through the acoustic-optical modulator 2, the optical pulses are subjected to power amplification through the erbium-doped fiber amplifier 3, the optical pulses are transmitted to the sensing fiber 6 through the conducting fiber 4, Rayleigh backscattered light generated by the sensing fiber 6 is received by the circulator 5 and corresponding Rayleigh backscattered light signals are output, the Rayleigh backscattered light signals are converted into Rayleigh backscattered electrical signals through the photoelectric detector 9, and the Rayleigh backscattered electrical signals are transmitted to the data acquisition card 7 for analog-to-digital conversion and then transmitted to the computer 8 for signal processing.
Referring to fig. 2, in a trajectory description method applied to an optical fiber sensing system, the performing signal processing includes the following steps:
s1: reading a Rayleigh backscattering signal;
s2: dividing the sensing optical fiber with the total length L into N equidistant intrusion prevention areas, wherein the length d of the intrusion prevention areas is [2nL/cTP]+1, where n is the refractive index of the fiber group, c is the vacuum light velocity, T is the duration of the light pulse, L is the total length of the sensing fiber, p is the pulse width, and the intrusion prevention area is represented by D ═ D1，d2，……dN]；
It should be noted that the total length of the sensing fiber can be set according to actual conditions, and the length d of the intrusion prevention area is determined by the pulse width of the laser.
S3: equally dividing the acquired Rayleigh backscattering signals into a plurality of time interval signal sets according to the acquisition time sequence of the data acquisition card, and expressing as F ═ F [ [ F [ ]1，F2，……FN]Wherein, each time interval signal set comprises M frames of Rayleigh backscattering signals, each frame of Rayleigh backscattering signals are equally divided into N defense areas corresponding to the invasion defense areasCalculating the total light intensity value of the M frames of Rayleigh backscattering signals in each time period signal set according to the scattered signals, and calculating the average light intensity value of each frame of Rayleigh backscattering signals in the time period signal set according to the total light intensity value of the M frames of Rayleigh backscattering signals in the time period signal set;
it should be noted that, referring to fig. 3, a two-dimensional plane line graph may be established, where a horizontal axis x is an intrusion prevention area, a vertical axis y is a rayleigh backscattering light intensity value, and the obtained rayleigh backscattering signal is correspondingly calibrated on the two-dimensional plane line graph according to the collection time sequence, so that the signal intensity change can be observed more intuitively, and in addition, in order to make the observation more intuitive, each frame of rayleigh backscattering signal value in each time period may be described by a gradient color.
S4: subtracting the light intensity value of each defense area Rayleigh backscattering signal belonging to the time interval signal set from the average light intensity value of each frame Rayleigh backscattering signal in the corresponding time interval signal set to obtain a light intensity difference, wherein the light intensity difference is represented as E1 ═ E1，e2，……ex]Repeating the steps to obtain the light intensity difference value set E ═ E in the period1，E2，……Ex]Repeating the operation to obtain light intensity difference value sets of N time periods;
s5: comparing each light intensity difference value in the light intensity difference value set of each time period with a preset disturbance difference threshold value one by one, and judging the intrusion defense area corresponding to the light intensity difference value set of the time period as a disturbance defense area N with disturbance when the light intensity difference value exceeds the preset disturbance difference threshold valuexAnd executing steps S6-S7;
it should be noted that the preset disturbance difference threshold is set according to the actual requirement of the worker, and in general, the preset disturbance difference threshold is 0.
S6: obtaining disturbance defense area NxCorresponding disturbance time and light intensity difference ExAnd obtaining adjacent disturbance defense areas N in front of and behind the disturbance defense areax-1And disturbance prevention area Nx+1Respectively corresponding light intensity difference Ex-1And Ex+1Obtaining the disturbance according to the negative correlation between the light intensity difference at the disturbance source and the light intensity difference at the central point of the disturbance prevention areaDynamic defense area NxAnd disturbance prevention area Nx-1And disturbance prevention area Nx+1Respectively corresponding radial distances r of optical fiber disturbance pointsx、rx-1And rx+1；
It should be noted that the disturbance defense area N is acquiredxThe corresponding disturbance time can be obtained by a timer preset in the computer, and can be used for marking the occurrence starting time, the duration time and the ending time of the disturbance source;
in addition, the negative correlation formula of the light intensity difference at the disturbance source and the light intensity difference at the central point of the disturbance prevention area is E ═ K1E0r-KWhere E is the difference in light intensity at the source of the disturbance, E0Difference in light intensity, K, for the central point of the disturbance zone1The radial distance r of the disturbance prevention area can be estimated according to the light intensity difference coefficient and the comprehensive attenuation coefficient Kx、rx-1And rx+1Can be according to the formula
Obtaining, wherein the light intensity difference coefficient and the comprehensive attenuation coefficient can be manually set in advance according to the actual environment or obtained by calibrating an intrusion prevention area on the optical fiber, specifically, knocking at the central point of the intrusion prevention area and knocking at preset distances r1 and r2 from the central point of the intrusion prevention area respectively to obtain light intensity differences E0, E1 and E2 respectively, and then utilizing a formula
Parameters K1 and K are obtained.
S7: referring to FIG. 4, the optical fiber is arranged on the same radial horizontal plane of the sensing fiber to disturb the defense area Nx、Nx-1And Nx+1Is taken as the center of a circle and respectively corresponds to the radial distance r of the optical fiber disturbance pointx、rx-1And rx+1Drawing a circle for the radius, wherein the intersection point of the three circles which are intersected together is the disturbance source position HxAnd repeating the operation, sequentially obtaining the position of the disturbance source in each time interval according to the acquisition time sequence of the data acquisition card, and connecting the disturbance points in all the time intervals according to the acquisition time sequence to obtain the motion trail of the disturbance source.
It should be noted that the negative correlation between the light intensity difference at the disturbance source and the light intensity difference at the center point of the disturbance prevention area is E-K1E0r-KThe radial distance r of the disturbance zone can be estimatedx、rx-1And rx+1Can be obtained from the following formula,
It will be appreciated that three circles to determine the source of disturbance may improve the accuracy of the positioning.
The embodiment, based on the optical fiber sensing system, can realize the track positioning of the disturbance source by adopting the intensity-time algorithm without additionally adding other hardware equipment, and calculates the light intensity difference set in each time interval by obtaining Rayleigh backward scattering light emitted by the sensing optical fiber and obtaining corresponding Rayleigh backward scattering signals, and comparing each light intensity difference value in the light intensity difference value set with a preset disturbance difference threshold value, thereby determining the disturbance defense area, respectively drawing circles in a plane by taking the center points of the disturbance defense area and the adjacent front and rear disturbance defense areas as the center of the circle to obtain the common point of the three circles as a disturbance source, repeating the operation, and sequentially obtaining the position of the disturbance source in each time interval, and connecting the disturbance points in all the time intervals according to the acquisition time sequence to obtain the motion trail of the disturbance source, so that the motion trail of the disturbance source is accurately and quickly positioned.
Further, step S5 specifically includes: and when the light intensity difference value is lower than the preset disturbance difference threshold value, judging that no disturbance action exists, and executing steps S1-S5.
It can be understood that the rayleigh backscattering signal acquisition and real-time signal processing can be continued when no perturbation action exists.
Further, step S7 is followed by: and establishing an electronic map corresponding to the intrusion prevention area, marking the intrusion prevention area in the electronic map, and correspondingly marking the motion trail of the disturbance source in the electronic map.
It can be understood that the movement track of the disturbance source is correspondingly calibrated in the electronic map, so that the movement track is displayed by combining the electronic map, and monitoring personnel can more conveniently, quickly and accurately predict the trend of the disturbance source.
Further, step S7 is followed by: and judging the motion trend of the disturbance source according to the motion track of the disturbance source, and informing a monitoring person to start a preset video monitoring device in the disturbance defense area.
It can be understood that whether to start the corresponding video monitoring device is judged according to the motion track of the disturbance source, so that the peripheral safety of the video monitoring device can be protected in real time, resources are saved, and the service life of the video monitoring device is prolonged.
Further, step S7 is followed by: and judging the motion trend of the disturbance source according to the motion trail of the disturbance source, and sequentially starting water flowing lamps preset in the disturbance prevention area according to the judged motion trend of the disturbance source and the time sequence.
It can be understood that the running water lamps preset in the disturbance defense area are sequentially turned on according to the judged movement trend of the disturbance source and the time sequence, so that the trend of the disturbance source is easier to judge by the staff on duty at night, and the fatigue of the staff on duty is reduced.
In the several embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.
The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.
The above embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions in the embodiments of the present application.
Claims (5)
1. A track description method applied to an optical fiber sensing system comprises a laser, an acousto-optic modulator, an erbium-doped optical fiber amplifier, a data acquisition card, a photoelectric detector, a circulator, a sensing optical fiber, a conducting optical fiber and a computer; after the laser generates laser beams, the laser beams are modulated into optical pulses through the acousto-optic modulator, the optical pulses are subjected to power amplification through the erbium-doped fiber amplifier, the optical pulses are transmitted to the sensing fiber through the conducting fiber, Rayleigh backscattered light generated by the sensing fiber is received by the circulator and correspondingly Rayleigh backscattered light signals are output, the Rayleigh backscattered light signals are converted into Rayleigh backscattered electrical signals through the photoelectric detector, and the Rayleigh backscattered electrical signals are transmitted to the data acquisition card for analog-to-digital conversion and then transmitted to the computer for signal processing; it is characterized in that the preparation method is characterized in that,
the signal processing comprises the following steps:
s1: reading the rayleigh backscatter signal;
s2: dividing the sensing optical fiber with the total length L into N equidistant intrusion prevention areas, wherein the length d of the intrusion prevention areas is [2nL/cTP]+1, where n is the refractive index of the optical fiber group, c is the vacuum speed of light, T is the duration of light pulse, L is the total length of the sensing optical fiber, p is the pulse width, and the intrusion prevention area is represented by D ═ D1，d2，……dN]；
S3: equally dividing the obtained Rayleigh backscattering signals into a plurality of time interval signal sets according to the acquisition time sequence of the data acquisition card, and expressing as F ═ F [ [ F [ ]1，F2，……FN]Wherein each time-interval signal set comprises M frames of the Rayleigh backscattering signals, each frame of the Rayleigh backscattering signals is equally divided into N defense area Rayleigh backscattering signals corresponding to the intrusion defense area, the total light intensity value of the M frames of the Rayleigh backscattering signals in each time-interval signal set is calculated, and the average light intensity value of each frame of the Rayleigh backscattering signals in the time-interval signal set is calculated according to the total light intensity value of the M frames of the Rayleigh backscattering signals in the time-interval signal set;
s4: subtracting the light intensity value of each defense area Rayleigh backscattering signal in the time interval signal set from the average light intensity value of each frame of the Rayleigh backscattering signal in the corresponding time interval signal set to obtain a light intensity difference, wherein the light intensity difference is represented as E1 ═ E1，e2，……ex]Repeating the steps to obtain the light intensity difference value set E ═ E in the period1，E2，……Ex]Repeating the operation to obtain the light intensity difference value sets of N time periods；
S5: comparing each light intensity difference value in the light intensity difference value set of each time interval with a preset disturbance difference threshold value one by one, and judging that the intrusion prevention area corresponding to the light intensity difference value set of the time interval is a disturbance prevention area N with disturbance when the light intensity difference value exceeds the preset disturbance difference threshold valuexAnd executing steps S6-S7;
s6: obtaining the disturbance defense area NxCorresponding disturbance time and light intensity difference ExAnd obtaining adjacent disturbance defense areas N in front of and behind the disturbance defense areax-1And disturbance prevention area Nx+1Respectively corresponding light intensity difference Ex-1And Ex+1Obtaining the disturbance defense area N according to the negative correlation relationship between the light intensity difference at the disturbance source and the light intensity difference at the central point of the disturbance defense areaxThe disturbance prevention area Nx-1And the disturbance prevention area Nx+1Respectively corresponding radial distances r of optical fiber disturbance pointsx、rx-1And rx+1Radial distance rx、rx-1And rx+1According to the formula
Calculated, wherein R is the radial distance, K is the comprehensive attenuation coefficient, E is the light intensity difference at the disturbance source, K1Is the light intensity difference coefficient, E0The light intensity difference value of the central point of the disturbance prevention area is obtained;
s7: on the same radial horizontal plane of the sensing optical fiber to disturb the defense area Nx、Nx-1And Nx+1Is taken as the center of a circle and respectively corresponds to the radial distance r of the optical fiber disturbance pointx、rx-1And rx+1Drawing a circle for the radius, wherein the intersection point of the three circles which are intersected together is the disturbance source position HxAnd repeating the operation, sequentially obtaining the position of the disturbance source in each time interval according to the acquisition time sequence of the data acquisition card, and connecting the disturbance points in all the time intervals according to the acquisition time sequence to obtain the motion trail of the disturbance source.
2. The trajectory description method applied to the optical fiber sensing system according to claim 1, wherein the step S5 further includes:
and when the light intensity difference value is lower than the preset disturbance difference threshold value, judging that no disturbance action exists, and executing the steps S1-S5.
3. The trajectory description method applied to the optical fiber sensing system according to claim 1, wherein the step S7 is followed by further comprising:
and establishing an electronic map corresponding to the intrusion prevention area, marking the intrusion prevention area in the electronic map, and correspondingly marking the motion trail of the disturbance source in the electronic map.
4. The trajectory description method applied to the optical fiber sensing system according to claim 1 or 3, wherein the step S7 is followed by further comprising:
and judging the motion trend of the disturbance source according to the motion track of the disturbance source, and informing a monitoring person to start a preset video monitoring device in the disturbance defense area.
5. The trajectory description method applied to the optical fiber sensing system according to claim 4, wherein the step S7 is followed by further comprising:
and judging the motion trend of the disturbance source according to the motion trail of the disturbance source, and sequentially starting water flowing lamps preset in the disturbance prevention area according to the judged motion trend of the disturbance source in a time sequence.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010877494.7A CN111982170B (en) | 2020-08-27 | 2020-08-27 | Track description method applied to optical fiber sensing system |
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| CN202010877494.7A CN111982170B (en) | 2020-08-27 | 2020-08-27 | Track description method applied to optical fiber sensing system |
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