An optical fiber positioning perimeter alarm system and method for air-ground joint multi-dimensional judgment

Abstract

The present invention discloses an optical fiber positioning type perimeter alarm system and method for joint multi-dimensional judgment of air and ground. The system includes an optical cable and a laser generating monitoring device laid along the perimeter. The laid optical cables are divided into guardrail sensing optical cables and ground sensing optical cables. The method includes: step 1: synchronously acquiring dual-cable vibration signal data respectively and effectively confirming the dual-cable vibration signals; step 2: extracting characteristic values ​​of the confirmed effective dual-cable vibration signals respectively; step 3: classifying and identifying the dual-cable vibration signals according to the extracted characteristic values; step 4: performing complementary detection and judgment according to the classification and recognition results of the dual-cable vibration signals. The present invention adopts a dual-cable complementary detection method to form multi-dimensional monitoring of air and ground, increase the protection area, and at the same time combine the dual-cable detection response judgment of intrusion events to improve the alarm accuracy, enhance the ability to resist emergencies, improve work efficiency, and achieve the purpose of safety protection.

Description

Technical Field

[0001] The present invention relates to the technical field of optical fiber sensing and perimeter security, and in particular to an optical fiber positioning perimeter alarm system and method for air-ground joint multi-dimensional judgment. Background Art

[0002] In recent years, fiber optic sensing technology has received more and more attention in the field of perimeter security due to its advantages such as being passive, anti-interference, and distributed long-distance real-time monitoring. Most of the equipment based on fiber optic sensing technology is based on the fiber grating principle, sagnic principle, scattering principle, etc., while the monitoring distance of fiber optic grating equipment is short and it is not easy to carry out long-distance monitoring; the positioning accuracy of sagnic principle equipment is poor, and the construction method is complicated and cumbersome; the technical equipment based on the scattering principle is widely used due to its high sensitivity, accurate positioning, easy construction, and can be used for long-distance monitoring. At present, most fiber optic perimeter systems are based on single-wavelength single-cable signal collection for analysis and judgment of alarms, which have problems such as difficult to eliminate complex interference signals, easy to generate false alarms, low accuracy, and poor ability to resist emergencies. Summary of the invention

[0003] The purpose of the present invention is to provide an optical fiber positioning perimeter alarm system and method for air-ground joint multi-dimensional judgment to solve the above technical problems.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] The present invention proposes an optical fiber positioning type perimeter alarm system for air-ground joint multi-dimensional judgment, comprising an optical cable laid along the perimeter and a laser generating monitoring device, characterized in that the laid optical cable is divided into two paths, one path is laid on the guardrail net arranged around the perimeter and is called the guardrail sensing optical cable, and the other path is laid under the ground of the guardrail net and is called the ground sensing optical cable, and the laser generating monitoring device comprises two lasers arranged in parallel, the two lasers emit lasers of different wavelengths, and the two lasers are sequentially connected to a first wavelength division multiplexer, a semiconductor laser amplifier, a first erbium-doped fiber amplifier, and a first dense A wavelength division multiplexer and two parallel circulators are integrated; the first outlets of the two circulators are respectively connected to the guardrail sensing optical cable and the ground sensing optical cable, the second outlets of the two circulators are sequentially connected to the second wavelength division multiplexer, the second erbium-doped fiber amplifier and the second dense wavelength division multiplexer, and two parallel detectors are connected after the second dense wavelength division multiplexer, and the outputs of the two detectors are connected to a signal processing server, the signal processing server includes a signal acquisition card, and the system also includes a waveform generator, which is respectively connected to the semiconductor laser amplifier and the signal acquisition card;

[0006] The first wavelength division multiplexer is used to superimpose two optical signals to form one optical signal; the first dense wavelength division multiplexer is used to restore the amplified optical signal to two optical signals and send them to two circulators respectively; the waveform generator is used as a standard signal source for the semiconductor laser amplifier to modulate and output the optical signal according to the waveform generator signal, and is also used as a sampling clock for the signal acquisition card;

[0007] The second wavelength division multiplexer is used to superimpose the guardrail sensing optical cable vibration light signal and the ground sensing optical cable vibration light signal received from the second outlets of the two circulators to form a beam of light signal, the second dense wavelength division multiplexer is used to restore the amplified light signal to the guardrail sensing optical cable vibration light signal and the ground sensing optical cable vibration light signal, the two parallel detectors are used to convert the respectively received guardrail sensing optical cable vibration light signal and the ground sensing optical cable vibration light signal into electrical signals, and the signal processing server is used to collect the electrical signals and analyze and process them to output the alarm processing results.

[0008] Furthermore, the laser is a narrow linewidth laser.

[0009] Furthermore, the binding spacing of the guardrail sensing optical cable is 35cm to 50cm.

[0010] Furthermore, the ground induction optical cable is laid close to the guardrail net or within 50 cm from the guardrail net, and the burial depth is 10 cm to 20 cm.

[0011] Furthermore, the guardrail sensing optical cable and the ground sensing optical cable are laid in a straight line, S-shaped or U-shaped manner.

[0012] Furthermore, the bending radius of the guardrail sensing optical cable and the ground sensing optical cable is not less than 15 cm.

[0013] The present invention also proposes an optical fiber positioning type perimeter alarm method for air-ground joint multi-dimensional judgment, the method comprising the following steps:

[0014] Step 1: synchronously obtain the vibration signal data of the guardrail sensing optical cable and the ground sensing optical cable respectively, and effectively confirm the vibration signals of the dual cables;

[0015] Step 2: Extract characteristic values ​​of the confirmed effective dual-cable vibration signals respectively;

[0016] Step 3: Classify and identify the dual-cable vibration signals according to the extracted characteristic values;

[0017] Step 4: Perform complementary detection and judgment based on the classification and recognition results of the dual-cable vibration signals: First, determine whether the dual cables are broken, and process the dual-cable recognition results as follows based on the judgment results:

[0018] 1) If there is no optical cable disconnection accident on site, the dual cable identification results are taken and operated;

[0019] 2) If any one of the two optical cables is broken, then the area after the break will be processed with or, and the area before the break will be processed with and.

[0020] Furthermore, the specific process of effectively confirming the dual-cable vibration signal in step 1 is as follows:

[0021] 1) The collected dual-cable vibration signals are divided into frames respectively, and the signal sequence obtained after the guardrail sensing optical cable vibration signal is divided into frames is recorded as x i (n), the signal sequence obtained after the ground induction cable vibration signal is framed is recorded as y i (n);

[0022] 2) Calculate the signal x i (n), y i The short-term energy value of (n):

[0023]

[0024] Where: a is a constant; or

[0025] 3) Set x i (n), y i (n) The high and low thresholds of the signal, and the number of times the signal exceeds the high and low thresholds is counted as A1 and A2 respectively;

[0026] 4) Statistics x i (n), y i (n) The number of vibration frames in the signal, for x i (n), y i (n) signal, taking its subsequent continuous multiple frame signals to form a vibration array, the number of vibration arrays containing vibration information is recorded as B1 and B2;

[0027] 5) Calculate the signal ratio difference coefficients C1 and C2:

[0028]

[0029] Where: Q k is the ratio of the kth vibration frame in the vibration array; is the average value of the kth vibration frame in the vibration array;

[0030] 6) Set the screening thresholds of short-time energy values ​​A1, A2, B1, B2, C1, and C2 respectively. When the short-time energy values ​​A1, A2, B1, B2, C1, and C2 are all greater than the respective set screening thresholds, it is confirmed that the vibration signal of the dual cables is valid.

[0031] Furthermore, the specific process of extracting the characteristic values ​​of the confirmed effective dual-cable vibration signals in step 2 is as follows:

[0032] 1) Define the collected and confirmed valid dual-cable vibration signal sequence as D i =x(t), i=1, 2, 3...;

[0033] 2) The maximum and minimum sequences obtained in the dual-cable vibration signal are defined as K i With M i , where K i With M i The value in is D i The horizontal coordinate value of the maximum or minimum point;

[0034] 3) Construct an order statistical filter and set the input to {X a}, the output is {Y a}, then the window size is: L = 2ω + 1, where ω is the minimum distance between adjacent extreme points, and the order statistical filter is used to calculate K i With M i The minimum distance between extreme points in K is obtained with a step size of 2ω+1. i 、M i The envelope of B 、M B ;

[0035] 4) Obtain the envelope mean line: S i =(K B +M B ) / 2; use mean smoothing filter to filter S i The curve is smoothed to make it continuous, and the smoothed mean curve is expressed as: where z t is the envelope with a wide mouth length of ω;

[0036] 5) Calculate the intrinsic mode function: F i =D i -S i ; i=i+1; D i =S i-1 , when the filter window size > D i 1 / 3 of the length or D i The process is terminated when the number of extreme value points is less than 3, otherwise, steps 2) to 5) are repeated;

[0037] 6) After reaching the cutoff condition, the original signal is decomposed into N intrinsic mode components and a residue R, which can be expressed as:

[0038]

[0039] 7) Calculate the kurtosis of each modal component using the following formula:

[0040]

[0041] Where: μ represents the signal average; σ represents the signal standard deviation; the kurtosis of the modal component is the eigenvalue.

[0042] Furthermore, the process of classifying and identifying the dual-cable vibration signals for alarm respectively in step 3 is as follows: classifying and identifying the eigenvalues ​​extracted from the dual-cable signals respectively, constructing a multi-kernel function by convex combination of linear kernel functions, polynomial kernel functions and Gaussian kernel functions, classifying the extracted eigenvalues ​​after constructing a multi-kernel SVM, outputting the alarm classification and identification results, giving an alarm to the intrusion signal according to the classification results, and displaying the corresponding location information according to the system monitoring results.

[0043] The beneficial effects of the present invention are as follows: the optical fiber positioning perimeter alarm system and method for joint multi-dimensional judgment of air and ground proposed by the present invention uses dual cables to collect vibration signals of two different dimensions in real time, extracts characteristic values ​​for classification and identification, and then combines the dual cable identification results for complementary detection and judgment. The present invention forms multi-dimensional monitoring of air and ground through dual-cable complementary detection, increases the protection area, and combines dual cables for intrusion event detection response judgment to improve the alarm accuracy. In addition, when one optical cable is disconnected, the cable break complementary mode is turned on and the system can still work, thereby enhancing the system's ability to resist emergencies, improving work efficiency, and achieving the purpose of safety protection.

[0044] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 This is a schematic diagram of the structure of the optical fiber positioning perimeter alarm system;

[0046] Figure 2 Schematic diagram of the optical cable laying structure;

[0047] Figure 3 This is a flow chart of the optical fiber positioning perimeter alarm method;

[0048] Figure 4 It is a waterfall diagram of the background noise signal of the guardrail sensing optical cable in windy and rainy weather;

[0049] Figure 5 It is a waterfall diagram of the knock response signal of the wind and rain weather guardrail sensing optical cable;

[0050] Figure 6 This is the waterfall diagram of the background noise signal of the ground sensing optical cable in windy and rainy weather;

[0051] Figure 7 This is a waterfall diagram of the ground induction optical cable walking signal in windy and rainy weather. DETAILED DESCRIPTION

[0052] The present invention proposes a fiber optic positioning type perimeter alarm system and method for air-ground joint multi-dimensional judgment, such as Figure 1 , Figure 2 As shown, the system includes an optical cable laid along the perimeter and a laser generation monitoring device. The laid optical cables are divided into two paths. One path is laid on the guardrail net set around the perimeter and is called the guardrail sensing optical cable. The other path is laid under the ground of the guardrail net and is called the ground sensing optical cable. The two optical cables are connected to the laser generation monitoring device through a guide optical cable. The laser generation monitoring device includes two lasers arranged in parallel, a first laser and a second laser. The two lasers emit lasers of different wavelengths. When one of the wavelength optical signals fails, the other wavelength optical signal can also work alone; the two lasers are then sequentially connected to a first wavelength division multiplexer, a semiconductor laser amplifier, a first erbium-doped fiber amplifier, a first dense wavelength division multiplexer and two circulators arranged in parallel. The first circulator A shaper and a second circulator, the first outlets of the two circulators are respectively connected to the guardrail sensing optical cable and the ground sensing optical cable, the second outlets of the two circulators are sequentially connected to the second wavelength division multiplexer, the second erbium-doped fiber amplifier and the second dense wavelength division multiplexer, the optical signal undergoes Rayleigh scattering during the optical fiber transmission process, and the backward Rayleigh scattered light enters the second wavelength division multiplexer through the first circulator and the second outlet of the second circulator respectively; two parallel detectors are connected after the second dense wavelength division multiplexer, the first detector and the second detector, the outputs of the two detectors are connected to the signal processing server, the signal processing server includes a signal acquisition card, and the system also includes a waveform generator, and the waveform generator is respectively connected to the semiconductor laser amplifier and the signal acquisition card.

[0053] The first wavelength division multiplexer is used to superimpose two optical signals to form one optical signal; the first dense wavelength division multiplexer is used to restore the amplified optical signal into two optical signals and send them into two circulators respectively; the waveform generator is used as a standard signal source, and is used for the semiconductor laser amplifier to modulate and output the optical signal according to the waveform generator signal, and is also used as the sampling clock of the signal acquisition card to ensure the synchronization of the front and rear signals.

[0054] The second wavelength division multiplexer is used to superimpose the guardrail sensing optical cable vibration light signal and the ground sensing optical cable vibration light signal received from the second outlets of the two circulators to form a beam of light signal, the second dense wavelength division multiplexer is used to restore the amplified light signal to the guardrail sensing optical cable vibration light signal and the ground sensing optical cable vibration light signal, the two parallel detectors are used to convert the respectively received guardrail sensing optical cable vibration light signal and the ground sensing optical cable vibration light signal into electrical signals, the signal processing server collects the electrical signals through the signal acquisition card and analyzes and processes them to output the alarm processing results.

[0055] Specifically, the laser used is a narrow linewidth laser. For the guardrail sensing optical cable and the ground sensing optical cable, the ground sensing optical cable is laid close to the guardrail net or within 50cm of the guardrail net, and the burial depth is 10cm to 20cm; the binding spacing of the guardrail sensing optical cable is 35cm to 50cm; the laying method of the optical cable can be straight, S-shaped or U-shaped; its bending radius is not less than 15cm to ensure that the optical cable does not have a large bend. In the actual process, a section of cable will be left at the fusion point of the optical cable (generally 10 to 30m is sufficient), and the cable needs to be fully fixed and firmly fixed. Cable winding or optical cable looping is not allowed at other positions of the guardrail, and the guardrail sensing optical cable should be in full contact with the guardrail as much as possible and fixed firmly to avoid increasing interference caused by looseness.

[0056] The optical fiber positioning perimeter alarm method disclosed in the present invention is as follows: Figure 3 As shown, the following steps are included:

[0057] Step 1: synchronously obtain the vibration signal data of the guardrail sensing optical cable and the ground sensing optical cable, and effectively confirm the dual-cable vibration signal; the specific process is as follows:

[0058] 1) The collected dual-cable vibration signals are divided into frames respectively, and the signal sequence obtained after the guardrail sensing optical cable vibration signal is divided into frames is recorded as x i (n), the signal sequence obtained after the ground induction cable vibration signal is framed is recorded as y i (n);

[0059] 2) Calculate the signal x i (n), y i The short-term energy value of (n):

[0060]

[0061] Where: a is a constant; or

[0062] 3) Set x i (n), y i(n) high and low threshold values ​​of the signal, and count the number of times the signal exceeds the high and low threshold values, which are A1 and A2 respectively; the high and low threshold values ​​are set based on multiple sets of signal amplitude values ​​obtained from the previous sample signal analysis, and a value that satisfies most samples is selected;

[0063] 4) Statistics x i (n), y i (n) The number of vibration frames in the signal, for x i (n), y i (n) signal, taking the subsequent continuous multi-frame signal, the number of frames of the signal is determined according to different application occasions, in this embodiment, 9 frames are taken to form a vibration array, and the number of vibration information contained in the vibration array is recorded as B1 and B2;

[0064] 5) Calculate the signal ratio difference coefficients C1 and C2:

[0065]

[0066] Where: Q k is the ratio of the kth vibration frame in the vibration array; is the average value of the kth vibration frame in the vibration array;

[0067] 6) Set the screening thresholds of the short-time energy values, A1, A2, B1, B2, C1, C2 respectively. When the short-time energy values, A1, A2, B1, B2, C1, C2 are all greater than the set screening thresholds, it is confirmed that the vibration signal of the dual cables is valid; wherein the screening thresholds of the short-time energy values, A1, A2, B1, B2, C1, C2 are set by selecting a value that satisfies most samples based on multiple groups of values ​​of the short-time energy values, A1, A2, B1, B2, C1, C2 obtained by analyzing the previous sample signals.

[0068] Step 2: Extract the characteristic values ​​of the confirmed effective dual-cable vibration signals respectively; the specific process is as follows:

[0069] 1) Define the collected and confirmed valid dual-cable vibration signal sequence as D i =x(t), i=1, 2, 3...;

[0070] 2) The maximum and minimum sequences obtained in the dual-cable vibration signal are defined as K i With M i , where K i With M i The value in is D i The horizontal coordinate value of the maximum or minimum point;

[0071] 3) Construct an order statistical filter and set the input to {X a}, the output is {Ya}, then the window size is: L = 2ω + 1, where ω is the minimum distance between adjacent extreme points, and the order statistical filter is used to calculate K i With M i The minimum distance between extreme points in K is obtained with a step size of 2ω+1. i 、M i The envelope of B 、M B ;

[0072] 4) Obtain the envelope mean line: S i =(K B +M B ) / 2; use mean smoothing filter to filter S i The curve is smoothed to make it continuous, and the smoothed mean curve is expressed as: where z t is the envelope with a wide mouth length of ω;

[0073] 5) Calculate the intrinsic mode function: F i =D i -S i ; i=i+1; D i =S i-1 , when the filter window size > D i 1 / 3 of the length or D i The process is terminated when the number of extreme value points is less than 3, otherwise, steps 2) to 5) are repeated;

[0074] 6) After reaching the cutoff condition, the original signal is decomposed into N intrinsic mode components and a residue R, which can be expressed as:

[0075]

[0076] 7) Calculate the kurtosis of each modal component using the following formula:

[0077]

[0078] Where: μ represents the signal average; σ represents the signal standard deviation; the kurtosis of the modal component is the eigenvalue.

[0079] Step 3: Classify and identify the dual-cable vibration signals according to the extracted eigenvalues; the specific process is: classify and identify the eigenvalues ​​extracted from the dual-cable signals, construct a multi-kernel function by convex combination of linear kernel function, polynomial kernel function and Gaussian kernel function, construct a multi-kernel SVM, classify the extracted eigenvalues, output the alarm classification and identification results, alarm the intrusion signal according to the classification results, and display the corresponding location information according to the system monitoring results.

[0080] Step 4: Perform complementary detection and judgment based on the classification and recognition results of the dual-cable vibration signals: First, determine whether the dual cables are broken, and process the dual-cable recognition results as follows based on the results of determining whether the dual cables are broken:

[0081] 1) If there is no optical cable disconnection accident on site, the dual cable identification results are taken and operated;

[0082] 2) If any one of the two optical cables is broken, then the area after the break will be processed by either or, and the area before the break will still be processed by either or.

[0083] The fiber optic positioning perimeter alarm system described in this embodiment uses the guardrail sensing optical cable and the ground sensing optical cable as front-end distributed sensors to sense the surrounding vibration signals. Figure 4 , Figure 5 As shown, the signal collected by the ground sensing optical cable in wind and rain weather is as follows Figure 6 , Figure 7 As shown in the figure, by comparing the signals collected by the dual cables, it can be seen that the background noise of the ground sensing optical cable is much lower than that of the guardrail sensing optical cable, and is almost unaffected by wind and rain. Therefore, combining the dual cables to detect and respond to intrusion events can form multi-dimensional monitoring of the air and ground, and improve the accuracy of the alarm.

[0084] Finally, it should be noted that the above is only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred arrangement scheme, a person skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. A fiber optic positioning perimeter alarm method for joint multi-dimensional judgment of air and ground, characterized in that: The method comprises the following steps: Step 1: synchronously obtain the vibration signal data of the guardrail sensing optical cable and the ground sensing optical cable respectively, and effectively confirm the vibration signals of the dual cables; The specific process of effectively confirming the dual-cable vibration signal is as follows: 1) The collected dual-cable vibration signals are divided into frames respectively, and the signal sequence obtained after the guardrail sensing optical cable vibration signal is divided into frames is recorded as x i (n), the signal sequence obtained after the ground induction cable vibration signal is framed is recorded as y i (n); 2) Calculate the signal x i (n), y i The short-term energy value of (n): Where: a is a constant; or 3) Set x i (n), y i (n) The high and low thresholds of the signal, and the number of times the signal exceeds the high and low thresholds is counted as A1 and A2 respectively; 4) Statistics x i (n), y i (n) The number of vibration frames in the signal, for x i (n), y i (n) signal, taking its subsequent continuous multiple frame signals to form a vibration array, the number of vibration arrays containing vibration information is recorded as B1 and B2; 5) Calculate the signal ratio difference coefficients C1 and C2: Where: Q k is the ratio of the kth vibration frame in the vibration array; is the average value of the kth vibration frame in the vibration array; 6) Set the screening thresholds of short-time energy values ​​A1, A2, B1, B2, C1, and C2 respectively. When the short-time energy values ​​A1, A2, B1, B2, C1, and C2 are all greater than the respective set screening thresholds, it is confirmed that the vibration signal of the dual cables is valid; Step 2: Extract characteristic values ​​of the confirmed effective dual-cable vibration signals respectively; The specific process of extracting the characteristic values ​​of the confirmed effective dual-cable vibration signals is as follows: 1) Define the collected and confirmed valid dual-cable vibration signal sequence as D i =x(t), i=1, 2, 3...; 2) The maximum and minimum sequences obtained in the dual-cable vibration signal are defined as K i With M i , where K i With M i The value in is D i The horizontal coordinate value of the maximum or minimum point; 3) Construct an order statistical filter and set the input to {X a }, the output is {Y a }, the window size is: L = 2ω + 1, where ω is the minimum distance between adjacent extreme points, and the order statistical filter is used to calculate k i With M i The minimum distance between extreme points in K is obtained with a step size of 2ω+1. i 、M i The envelope of B 、M B ; 4) Obtain the envelope mean line: S i =(K B +M B ) / 2; use mean smoothing filter to filter S i The curve is smoothed to make it continuous, and the smoothed mean curve is expressed as: where z t is the envelope with a wide mouth length of ω; 5) Calculate the intrinsic mode function: F i =D i -S i ; i=i+1; D i =S i-1 , when the filter window size > D i 1 / 3 of the length or D i The process is terminated when the number of extreme value points is less than 3, otherwise, steps 2) to 5) are repeated; 6) After reaching the cutoff condition, the original signal is decomposed into N intrinsic mode components and a residue R, which can be expressed as: 7) Calculate the kurtosis of each modal component using the following formula: Where: μ represents the signal average; σ represents the signal standard deviation; the kurtosis of the modal component is the eigenvalue; Step 3: Classify and identify the dual-cable vibration signals according to the extracted characteristic values; Step 4: Perform complementary detection and judgment based on the classification and recognition results of the dual-cable vibration signals: First, determine whether the dual cables are broken, and process the dual-cable recognition results as follows based on the judgment results: 1) If there is no optical cable disconnection accident on site, the dual cable identification results are taken and operated; 2) If any one of the two optical cables is broken, then the area after the break will be processed with or, and the area before the break will be processed with and.

2. The optical fiber positioning type perimeter alarm method of air-ground joint multi-dimensional judgment according to claim 1 is characterized in that: The process of classifying and identifying the dual-cable vibration signals for alarms described in step 3 is as follows: classifying and identifying the eigenvalues ​​extracted from the dual-cable signals, constructing a multi-kernel function by convex combination of linear kernel functions, polynomial kernel functions and Gaussian kernel functions, classifying the extracted eigenvalues ​​after constructing a multi-kernel SVM, outputting the alarm classification and identification results, giving an alarm to the intrusion signal according to the classification results, and displaying the corresponding location information according to the system monitoring results.

3. An optical fiber positioning type perimeter alarm system for air-ground joint multi-dimensional judgment using the method of claim 1, comprising an optical cable laid along the perimeter and a laser generating monitoring device, characterized in that: The laid optical cable is divided into two routes, one route is laid on the guardrail net arranged around the perimeter and is called the guardrail sensing optical cable, and the other route is laid under the ground of the guardrail net and is called the ground sensing optical cable. The laser generation monitoring device includes two lasers arranged in parallel, and the two lasers emit lasers of different wavelengths. The two lasers are sequentially connected to a first wavelength division multiplexer, a semiconductor laser amplifier, a first erbium-doped fiber amplifier, a first dense wavelength division multiplexer and two circulators arranged in parallel; the first outlets of the two circulators are respectively connected to the guardrail sensing optical cable and the ground sensing optical cable, and the second outlets of the two circulators are sequentially connected to a second wavelength division multiplexer, a second erbium-doped fiber amplifier and a second dense wavelength division multiplexer, and two detectors arranged in parallel are connected after the second dense wavelength division multiplexer, and the outputs of the two detectors are connected to a signal processing server, and the signal processing server includes a signal acquisition card. The system also includes a waveform generator, and the waveform generator is respectively connected to the semiconductor laser amplifier and the signal acquisition card; The first wavelength division multiplexer is used to superimpose two optical signals to form one optical signal; the first dense wavelength division multiplexer is used to restore the amplified optical signal to two optical signals and send them to two circulators respectively; the waveform generator is used as a standard signal source for the semiconductor laser amplifier to modulate and output the optical signal according to the waveform generator signal, and is also used as a sampling clock for the signal acquisition card; The second wavelength division multiplexer is used to superimpose the guardrail sensing optical cable vibration light signal and the ground sensing optical cable vibration light signal received from the second outlets of the two circulators to form a beam of light signal, the second dense wavelength division multiplexer is used to restore the amplified light signal to the guardrail sensing optical cable vibration light signal and the ground sensing optical cable vibration light signal, the two parallel detectors are used to convert the respectively received guardrail sensing optical cable vibration light signal and the ground sensing optical cable vibration light signal into electrical signals, and the signal processing server is used to collect the electrical signals and analyze and process them to output the alarm processing results.

4. The optical fiber positioning type perimeter alarm system for air-ground joint multi-dimensional judgment according to claim 3 is characterized in that: The laser is a narrow line width laser.

5. The optical fiber positioning type perimeter alarm system with air-ground joint multi-dimensional judgment according to claim 3 is characterized in that: The binding spacing of the guardrail sensing optical cable is 35cm to 50cm.

6. The optical fiber positioning type perimeter alarm system for air-ground joint multi-dimensional judgment according to claim 3 is characterized in that: The ground induction optical cable is laid close to the guardrail net or within 50 cm from the guardrail net, and the burial depth is 10 cm to 20 cm.

7. The optical fiber positioning type perimeter alarm system for air-ground joint multi-dimensional judgment according to claim 3 is characterized in that: The guardrail induction optical cable and the ground induction optical cable are laid in a straight line, S-shaped or U-shaped manner.

8. The optical fiber positioning type perimeter alarm system for air-ground joint multi-dimensional judgment according to claim 3 is characterized in that: The bending radius of the guardrail sensing optical cable and the ground sensing optical cable is not less than 15 cm.

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