Summary of the invention
It is an object of the invention to overcome the deficiency of the prior art, provides a kind of single-ended detection Brillouin's dynamic raster sensing
Method and device thereof.
The present invention solves the first technical solution used by its technical problem:
A kind of method of single-ended detection Brillouin's dynamic raster sensing comprising following steps:
A: the optical signal that a laser exports is divided into two-way and is modulated into two-way pulsed optical signals respectively as pumping pulse
Signal, the two-way pumping pulse signal frequency differ Brillouin shift;
B: the two-way pumping pulse signal timesharing enters sensor fibre, wherein pumping pulse signal reflex returns to biography all the way
Photosensitive fine and another way pumping pulse signal, which transmits to meet in sensor fibre in opposite directions, generates stimulated Brillouin scattering formation dynamic
Grating;
C: the optical signal modulation that another laser is exported is moved at sensor fibre is entered after direct impulse light to by Brillouin
Direct impulse light after state optical grating reflection carries out signal conversion and acquisition;
D: step C is repeated to reconstruct Brillouin's dynamic raster reflectance spectrum letter after adjusting the frequency of another laser output signal
Number, Brillouin's dynamic raster reflectance spectrum centre frequency is calculated, is used for the sensing of temperature and strain on sensor fibre;
E: according to Brillouin's dynamic raster reflectance spectrum centre frequency vBDGWith the relationship of strain stress: vBDG=νBDG0+Cvεε is completed
The measurement of strain stress on sensor fibre, according to Brillouin's dynamic raster reflectance spectrum centre frequency vBDGWith the relationship of temperature T: νBDG=
vBDG0+CvTT completes the measurement of temperature T on sensor fibre, wherein vBDG0For initial Brillouin's dynamic raster reflectance spectrum center frequency
Rate, CvεIt is the coefficient of strain, CvTIt is temperature coefficient.
In a further preferred embodiment, in the step B, the pulse width of pulse signal is pumped by controlling the two-way
Control the length that the Brillouin scattering forms dynamic raster.
In a further preferred embodiment, in the step B, the delays time to control of pulse signal is pumped by adjusting the two-way
The Brillouin scattering forms the position of dynamic raster.
The present invention solves second of technical solution used by its technical problem:
A kind of device of single-ended detection Brillouin's dynamic raster sensing comprising pulse signal source, first laser device, optical fiber
Beam splitter, the first electrooptic modulator, microwave signal source, filter, the first EDFA Erbium-Doped Fiber Amplifier, the second electrooptic modulator, height
Fast photoswitch, third electrooptic modulator, the second EDFA Erbium-Doped Fiber Amplifier, polarization-maintaining isolator, the first fibre optic polarizer, polarization beam splitting
Bundling device, sensor fibre, the second fibre optic polarizer, polarization-maintaining retroeflector, second laser, the 4th electrooptic modulator, third
EDFA Erbium-Doped Fiber Amplifier, polarization-maintaining circulator, third fibre optic polarizer, photodetector and data acquisition module;Described first swashs
Light device output end is connected with fiber optic splitter input terminal, the input of the first output end and the first electrooptic modulator of fiber optic splitter
End is connected, and microwave signal source output terminal is connected with the microwave input port of the first electrooptic modulator of electric light, and the first electrooptic modulator is defeated
Outlet is connected with filter input end, and filter output is connected with the first EDFA Erbium-Doped Fiber Amplifier input terminal, and first mixes bait light
Fiber amplifier output end is connected with the second electrooptic modulator input terminal, the first output end and the second Electro-optical Modulation of pulse signal source
Device bias input is connected, and the second electrooptic modulator output end is connected with high-speed optical switch input terminal;The second of fiber optic splitter
Output end is connected with third electrooptic modulator input terminal, and the second output terminal and third electrooptic modulator bias of pulse signal source are defeated
Enter end to be connected, third electrooptic modulator output end is connected with the second input terminal of high-speed optical switch;High-speed optical switch output end with
Second EDFA Erbium-Doped Fiber Amplifier input terminal is connected, and the second EDFA Erbium-Doped Fiber Amplifier output end is connected with polarization-maintaining isolator input terminal,
Polarization-maintaining isolator output end is connected with the first fibre optic polarizer input terminal, and the first fibre optic polarizer output end and polarization beam splitting close beam
Device slow axis input terminal is connected, and polarization beam splitter/combiner output end is connected with sensor fibre one end, the sensor fibre other end and second
Fibre optic polarizer input terminal is connected, and the second fibre optic polarizer output end is connected with polarization-maintaining retroeflector input terminal;Described second
Laser output is connected with the 4th electrooptic modulator input terminal, and pulse signal source third output end and the 4th electrooptic modulator are inclined
Input terminal is pressed to be connected, the 4th electrooptic modulator output end is connected with third EDFA Erbium-Doped Fiber Amplifier input terminal, third erbium-doped fiber
Amplifier out is connected with 1 end of polarization-maintaining circulator, and 2 end of polarization-maintaining circulator is connected with third fibre optic polarizer input terminal, third
Fibre optic polarizer output end is connected with polarization beam splitter/combiner fast axle input terminal;3 end of polarization-maintaining circulator and photodetector input
End is connected, and photodetector output end is connected with data acquisition module input terminal, data acquisition module synchronous output end and pulse
Signal source synchronous input end is connected.
In a further preferred embodiment, the pulse signal that second electrooptic modulator and third electrooptic modulator export
The time is exported there are the time difference, the time difference is by the pulse signal source for second electrooptic modulator and third electricity
The different driving time of optical modulator is adjusted.
In a further preferred embodiment, the pulse letter of second electrooptic modulator and third electrooptic modulator output
Number passing through the high-speed optical switch timesharing exports, wherein the pulse signal of second electrooptic modulator output is than the third
The pulse signal of electrooptic modulator output first passes through the high-speed optical switch output.
In a further preferred embodiment, what the pulse signal source generated is used to that the pulse of the 4th electrooptic modulator to be driven to believe
Number rising edge time point immediately following the pulse signal source generate for driving the pulse signal of third electrooptic modulator
Failing edge.
In a further preferred embodiment, the second laser uses the adjustable narrow linewidth laser of frequency.
The beneficial effects of the present invention are:
1, single-ended detection is belonged to using Brillouin's dynamic raster sensing device structure, the case where not reducing distance sensing
Under, it is routed sensor fibre in practical projects more flexible efficient, has further expanded the usage range of the sensor-based system.
2, the length of dynamic raster is formed by the pulse width control Brillouin scattering that control two-way pumps pulse signal,
The delays time to control Brillouin scattering that pulse signal is pumped by adjusting two-way forms the position of dynamic raster, realizes random length
Brillouin's grating appears in any position on optical fiber.
3, pumping pulse all the way is made to be reflected back sensor fibre and another way pumping pulse by using polarization-maintaining retroeflector
It meets and stimulated Brillouin scattering formation Brillouin's dynamic raster occurs;By using fibre optic polarizer can prevent direct impulse light
Signal reflex returns sensor fibre and then influences the detection of transducing signal.
3, by using the detection light of the adjustable narrow linewidth second laser injection different frequency of frequency, Brillouin is reconstructed
Dynamic raster reflects spectrum signal, and Brillouin's dynamic raster reflectance spectrum centre frequency is calculated, and is used on sensor fibre warm
The sensing of degree and strain.
Invention is further described in detail with reference to the accompanying drawings and embodiments;But a kind of single-ended detection cloth of the invention
In the method and device thereof of deep dynamic raster sensing be not limited to the embodiment.
Embodiment, shown in Figure 1, the device of the single-ended detection Brillouin's dynamic raster sensing of one kind of the invention, including
Pulse signal source 1, first laser device 2, fiber optic splitter 3, the first electrooptic modulator 4, microwave signal source 5, filter 6, first
EDFA Erbium-Doped Fiber Amplifier 7, the second electrooptic modulator 8, high-speed optical switch 9, third electrooptic modulator 10, the amplification of the second erbium-doped fiber
Device 11, polarization-maintaining isolator 12, the first fibre optic polarizer 13, polarization beam splitter/combiner 14, sensor fibre 15, the second fibre optic polarizer
16, the adjustable narrow linewidth second laser 18 of polarization-maintaining retroeflector 17, frequency, the 4th electrooptic modulator 19, third mix bait
Fiber amplifier 20, polarization-maintaining circulator 21, third fibre optic polarizer 22, photodetector 23 and data acquisition module 24;It is described
2 output end of first laser device is connected with 3 input terminal of fiber optic splitter, the first output end of fiber optic splitter 3 and the first electric light tune
The input terminal of device 4 processed is connected, and 5 output end of microwave signal source is connected with the microwave input port of the first electrooptic modulator of electric light, and first
4 output end of electrooptic modulator is connected with 6 input terminal of filter, 7 input terminal of 6 output end of filter and the first EDFA Erbium-Doped Fiber Amplifier
It is connected, 7 output end of the first EDFA Erbium-Doped Fiber Amplifier is connected with 8 input terminal of the second electrooptic modulator, and the first of pulse signal source 1 is defeated
Outlet is connected with 8 bias input of the second electrooptic modulator, 8 output end of the second electrooptic modulator and 9 input terminal of high-speed optical switch
It is connected;The second output terminal of fiber optic splitter 3 is connected with 10 input terminal of third electrooptic modulator, and the second of pulse signal source 1 is defeated
Outlet is connected with 10 bias input of third electrooptic modulator, and the of 10 output end of third electrooptic modulator and high-speed optical switch 9
Two input terminals are connected;9 output end of high-speed optical switch is connected with 11 input terminal of the second EDFA Erbium-Doped Fiber Amplifier, and the second erbium-doped fiber is put
Big 11 output end of device is connected with 12 input terminal of polarization-maintaining isolator, and 12 output end of polarization-maintaining isolator and the first fibre optic polarizer 13 input
End is connected, and 13 output end of the first fibre optic polarizer is connected with 14 slow axis input terminal of polarization beam splitter/combiner, polarization beam splitter/combiner
14 output ends are connected with 15 one end of sensor fibre, and 15 other end of sensor fibre is connected with 16 input terminal of the second fibre optic polarizer, the
Two fibre optic polarizers, 16 output end is connected with 17 input terminal of polarization-maintaining retroeflector;18 output end of second laser and the 4th
19 input terminal of electrooptic modulator is connected, and 1 third output end of pulse signal source is connected with 19 bias input of the 4th electrooptic modulator,
4th electrooptic modulator, 19 output end is connected with 20 input terminal of third EDFA Erbium-Doped Fiber Amplifier, and third EDFA Erbium-Doped Fiber Amplifier 20 is defeated
Outlet is connected with 211 end of polarization-maintaining circulator, and 212 end of polarization-maintaining circulator is connected with 22 input terminal of third fibre optic polarizer, third light
Fine 22 output end of polarizer is connected with 14 fast axle input terminal of polarization beam splitter/combiner;213 end of polarization-maintaining circulator and photodetector
23 input terminals are connected, and 23 output end of photodetector is connected with 24 input terminal of data acquisition module, and data acquisition module 24 is synchronous
Output end is connected with 1 synchronous input end of pulse signal source.
The present embodiment realization sensing method the following steps are included:
Step A: 2 output optical signal of first laser device is divided into two-way through fiber optic splitter 3 and respectively enters the first electric light tune
Device 4 and third electrooptic modulator 10 processed adjust microwave signal source 5, it is made to export the Brillouin of microwave signal sensor fibre 15
Frequency displacement, the first electrooptic modulator 4 of driving generate double-sideband signal and export to filter 6, adjust 6 passband of filter, export high frequency
Sideband signals enter the first EDFA Erbium-Doped Fiber Amplifier 7 and amplify and input the second electrooptic modulator 8, the second electrooptic modulator 8
Under the driving of pulse signal source 1, pulsed optical signals are exported as the first pumping pulse signal;Third electrooptic modulator 10 is in pulse
The lower pulsed optical signals that generate of the driving of signal source 1 are as the second pumping pulse signal, the first pumping pulse signal and the second pumping arteries and veins
Rush signal frequency difference Brillouin shift;
Step B: setting light opens the light switching cycle, and the first pumping pulse first passes through high-speed optical switch 9, and the second erbium-doped fiber is put
Through 14 slow axis end of polarization-maintaining isolator 12 and 13 input polarization beam splitter/combiner of the first fibre optic polarizer after the big amplification of device 11, sensing
It is transmitted to end in optical fiber 15 and is reflected back the biography of sensor fibre 15 into the second fibre optic polarizer 16 and through polarization-maintaining retroeflector 17
It is defeated;Second pumping pulse passes through photoswitch after the amplification of the second EDFA Erbium-Doped Fiber Amplifier 11 through polarization-maintaining isolator 12 and the first light again
Fine 13 input polarization beam splitter/combiner of polarizer, 14 slow axis input terminal pumps arteries and veins with reflected first in sensor fibre 15
The opposite transmission of punching adjusts pulse signal source 1 for the driving time of the second electrooptic modulator 8, may make the first pumping pulse and
Second pumping pulse is met in 15 any position of sensor fibre occurs stimulated Brillouin scattering formation Brillouin's dynamic raster, passes through
The pulse width control Brillouin scattering for controlling the first pumping pulse signal and the second pumping pulse signal forms dynamic raster
Length;
Step C: second laser 18 is that narrow linewidth laser is adjusted in frequency, outputs signal to the 4th electrooptic modulator
19, the 4th electrooptic modulator 19 under the driving of pulse signal source 1, put through third EDFA Erbium-Doped Fiber Amplifier 20 by output direct impulse light
Through polarization-maintaining circulator 21 and the fast shaft end of 22 input polarization beam splitter/combiner of third fibre optic polarizer 14 after big, into sensor fibre
15, the time for entering sensor fibre 15 can be adjusted by pulse signal source 1, make direct impulse rising edge immediately following the second pumping arteries and veins
Failing edge is rushed, signal is reflected back at Brillouin's dynamic raster through polarization beam splitter/combiner 14, third fibre optic polarizer 22 and is protected
Inclined circulator 21 enters photodetector 23 and carries out photoelectric conversion, and the electric signal after conversion is sent into data acquisition module 24 and is converted
At digital signal and save;
Step D: adjusting 18 frequency of second laser, repeats step C, and reconstruct Brillouin's dynamic raster reflects spectrum signal, meter
Calculation obtains Brillouin's dynamic raster reflectance spectrum centre frequency, is used for the sensing of temperature and strain on sensor fibre 15;
Step E: according to Brillouin's dynamic raster reflectance spectrum centre frequency vBDGWith the relationship of strain stress:
vBDD=νBDG0+Cvεε completes the measurement of strain stress on sensor fibre 15, according in Brillouin's dynamic raster reflectance spectrum
Frequency of heart νBDGWith the relationship of temperature T: vBDG=vBDG0+CvTT completes the measurement of temperature T on sensor fibre 15, wherein νBDG0For
Initial Brillouin's dynamic raster reflectance spectrum centre frequency, CvεIt is the coefficient of strain, CvTIt is temperature coefficient.
The present embodiment belongs to single-ended detection using Brillouin's dynamic raster sensing device structure, is not reducing distance sensing
In the case of, it is routed sensor fibre in practical projects more flexible efficient, has further expanded the usage range of the sensor-based system.
Above-described embodiment is only used to further illustrate the side of the single-ended detection Brillouin's dynamic raster sensing of one kind of the invention
Method and its device, but the invention is not limited to embodiments, are made according to the technical essence of the invention to above embodiments
Any simple modification, equivalent change and modification, fall within the scope of protection of technical solution of the present invention.