CN109375534A - A kind of synchronisation control means and system of the acquisition of Rayleigh brillouin scattering signal and detection - Google Patents
A kind of synchronisation control means and system of the acquisition of Rayleigh brillouin scattering signal and detection Download PDFInfo
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- CN109375534A CN109375534A CN201811114433.4A CN201811114433A CN109375534A CN 109375534 A CN109375534 A CN 109375534A CN 201811114433 A CN201811114433 A CN 201811114433A CN 109375534 A CN109375534 A CN 109375534A
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/04—Programme control other than numerical control, i.e. in sequence controllers or logic controllers
- G05B19/042—Programme control other than numerical control, i.e. in sequence controllers or logic controllers using digital processors
- G05B19/0423—Input/output
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
- G05B2219/20—Pc systems
- G05B2219/24—Pc safety
- G05B2219/24215—Scada supervisory control and data acquisition
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- Optical Modulation, Optical Deflection, Nonlinear Optics, Optical Demodulation, Optical Logic Elements (AREA)
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Abstract
The present invention discloses the synchronisation control means of a kind of Rayleigh brillouin scattering signal acquisition and detection, the following steps are included: step S1, the acquisition control command from host computer, parsing control command obtains the control information of voltage of F-P scanning interferometer, and control information of voltage includes synchronization time；Step S2, frequency-selecting is acquired to Rayleigh brillouin scattering signal according to control information of voltage control F-P scanning interferometer, meanwhile, control PMT single photon counter carries out detection counting to Rayleigh brillouin scattering signal；Step S3, timing is carried out to the gate time of the frequency-selecting time of F-P scanning interferometer and PMT single photon technique device, and judge whether frequency-selecting time and gate time reach synchronization time, if it is, it then controls F-P scanning interferometer and stops frequency-selecting, and control PMT single photon counter and stop counting, otherwise continue frequency-selecting and counting.The complete spectrum figure of the available Rayleigh brillouin scattering signal of the present invention.
Description
Technical field
The present invention relates to laser radar technique fields, and in particular to a kind of acquisition of Rayleigh brillouin scattering signal and detection
Synchronisation control means and system.
Background technique
Rayleigh Brillouin scattering needs to convert optical signal into electric signal, Cai Nengjin after F-P scanning interferometer frequency-selecting
The subsequent data processing of row.Since scattering light is more faint, need using photoelectron detector, the sub- detector of conventional photo can only
Duration is needed when detection light time spectrum for the energy of detection moment, thus is dissipated to obtain complete Rayleigh Brillouin
Spectral information is penetrated, it is extremely important for designing the isochronous controller of F-P cavity and PMT single photon counter.
Summary of the invention
It is an object of the invention to overcome above-mentioned technical deficiency, a kind of acquisition of Rayleigh brillouin scattering signal and detection are provided
Synchronisation control means and system, solve in the prior art F-P scanning interferometer it is asynchronous with PMT single photon counter, cause
The technical issues of spectral information is imperfect, spectrographic detection low efficiency.
To reach above-mentioned technical purpose, technical solution of the present invention provides a kind of Rayleigh brillouin scattering signal acquisition and inspection
The synchronisation control means of survey, comprising the following steps:
Step S1, control command is obtained from host computer, is parsed the control command and is obtained the control of F-P scanning interferometer
Information of voltage, the control information of voltage includes synchronization time；
Step S2, the F-P scanning interferometer is controlled to Rayleigh brillouin scattering signal according to the control information of voltage
It is acquired frequency-selecting, meanwhile, control PMT single photon counter carries out detection counting to the Rayleigh brillouin scattering signal；
Step S3, the gate time of the frequency-selecting time to the F-P scanning interferometer and the PMT single photon technique device
Timing is carried out, and judges whether the frequency-selecting time and the gate time reach the synchronization time, if it is, control
The F-P scanning interferometer stops frequency-selecting, and controls the PMT single photon counter and stop counting, and otherwise continues frequency-selecting
And it counts.
The present invention also provides a kind of Rayleigh brillouin scattering signals to acquire the synchronous control system with detection, including upper
Machine, control circuit, F-P scanning interferometer and PMT single photon counter, the control circuit include fpga chip and crystal oscillator
Circuit；
The fpga chip and the upper mechatronics, and for obtaining control command, parsing from the host computer
The control command obtains the control information of voltage of F-P scanning interferometer, and the control information of voltage includes synchronization time；
The fpga chip is electrically connected with the F-P scanning interferometer and PMT single photon counter respectively, and is used for,
The F-P scanning interferometer is controlled according to the control information of voltage, and the same of frequency-selecting is acquired to Rayleigh brillouin scattering signal
When, control PMT single photon counter carries out detection counting to the Rayleigh brillouin scattering signal；
The crystal oscillating circuit is electrically connected with the fpga chip, and for the frequency-selecting time to the F-P scanning interferometer
And the gate time of the PMT single photon technique device carries out timing；
When the fpga chip is also used to judge whether the frequency-selecting time and the gate time reach described synchronous
Between, if it is, controlling the F-P scanning interferometer stops frequency-selecting, and controls the PMT single photon counter and stops counting,
Otherwise continue frequency-selecting and counting.
Compared with prior art, the beneficial effect comprise that the present invention passes through to F-P scanning interferometer and PMT
The synchronously control of single photon counter realizes the complete acquisition of Rayleigh Brillouin scattering spectral information；Pass through setting PMT simultaneously
Single photon counter, improves the gain and sensitivity of spectrographic detection, and can keep preferable signal-to-noise ratio.
Detailed description of the invention
Fig. 1 is the flow chart of Rayleigh brillouin scattering signal acquisition and the synchronisation control means of detection provided by the invention；
Fig. 2 is the structural representation of Rayleigh brillouin scattering signal acquisition and the synchronous control system of detection provided by the invention
Figure.
In attached drawing: 1, host computer, 2, control circuit, 21, fpga chip, 22, crystal oscillating circuit, 23, digital analog converter, 24,
Memory, 3, F-P scanning interferometer, 4, PMT single photon counter.
Specific embodiment
In order to make the objectives, technical solutions, and advantages of the present invention clearer, with reference to the accompanying drawings and embodiments, right
The present invention is further elaborated.It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, and
It is not used in the restriction present invention.
Embodiment 1:
As shown in Figure 1, to provide a kind of acquisition of Rayleigh brillouin scattering signal synchronous with what is detected for the embodiment of the present invention 1
Control method, comprising the following steps:
Step S1, control command is obtained from host computer, is parsed the control command and is obtained the control of F-P scanning interferometer
Information of voltage, the control information of voltage includes synchronization time；
Step S2, the F-P scanning interferometer is controlled to Rayleigh brillouin scattering signal according to the control information of voltage
It is acquired frequency-selecting, meanwhile, control PMT single photon counter carries out detection counting to the Rayleigh brillouin scattering signal；
Step S3, the gate time of the frequency-selecting time to the F-P scanning interferometer and the PMT single photon technique device
Timing is carried out, and judges whether the frequency-selecting time and the gate time reach the synchronization time, if it is, control
The F-P scanning interferometer stops frequency-selecting, and controls the PMT single photon counter and stop counting, and otherwise continues frequency-selecting
And it counts.
The present invention is PMT single photon meter by the synchronously control to F-P scanning interferometer and PMT single photon counter
Number device provides lasting gate time section, thus available complete Rayleigh Brillouin scattering spectral information；Pass through simultaneously
PMT single photon counter is set, improves the gain and sensitivity of spectrographic detection, and preferable signal-to-noise ratio can be kept.This
Invention uses PMT single photon counter, compared with the photon counter based on avalanche photodide (APD), PMT single photon meter
Number device gain is higher, and multiplication factor can still keep fairly good signal-to-noise ratio up to 103-107 times while high-gain, and
And PMT single photon counter can detect very faint optical signal, identical photosurface size, detectivity is higher.
Preferably, the F-P scanning interferometer is controlled to Rayleigh cloth according to the control information of voltage in the step S2
In deep scattered signal be acquired frequency-selecting and specifically include:
Step S21, control voltage is generated according to the control information of voltage；
Step S22, the F-P scanning interferometer receive the control voltage and to the Rayleigh brillouin scattering signal into
Row frequency-selecting.
Parse control information of voltage from control command, control information of voltage includes the output area for controlling voltage, same
Walk the information such as time, interval time and falling waveform；Meet control information of voltage requirement according to control information of voltage output
Voltage is controlled, F-P scanning interferometer carries out frequency-selecting under control of a control voltage, and control information of voltage includes synchronization time, because
This, when the frequency-selecting time reaching synchronization time, F-P scanning interferometer stops frequency-selecting；While frequency-selecting, to PMT single photon counting
The pulse signal of device input is counted, until synchronization time terminates, realizes F-P scanning interferometer and PMT single photon meter
The synchronously control of number device, ensure that the complete acquisition of spectral information
Preferably, synchronisation control means further includes step S4, obtains spectral information according to frequency-selecting result and count results,
And real-time display and storage are carried out to the spectral information.
Spectral information is shown and is stored, checks and obtains convenient for user.
Embodiment 2
The embodiment of the present invention 2 provides the synchronous control system of a kind of Rayleigh brillouin scattering signal acquisition and detection,
Including host computer 1, control circuit 2, F-P scanning interferometer 3 and PMT single photon counter 4, the control circuit 2 includes
Fpga chip 21 and crystal oscillating circuit 22；
The fpga chip 21 is electrically connected with the host computer 1, and for obtaining control command from the host computer 1,
It parses the control command and obtains the control information of voltage of F-P scanning interferometer 3, when the control information of voltage includes synchronous
Between；
The fpga chip 21 is electrically connected with the F-P scanning interferometer 3 and PMT single photon counter 4 respectively, is used in combination
In controlling the F-P scanning interferometer 3 according to the control information of voltage and be acquired frequency-selecting to Rayleigh brillouin scattering signal
While, control PMT single photon counter 4 carries out detection counting to the Rayleigh brillouin scattering signal；
The crystal oscillating circuit 22 is electrically connected with the fpga chip 21, and for the frequency-selecting to the F-P scanning interferometer 3
The gate time of time and the PMT single photon technique device 4 carries out timing；
The fpga chip 21 is also used to judge whether the frequency-selecting time and the gate time reach the synchronization
Time if it is, controlling the F-P scanning interferometer 3 stops frequency-selecting, and controls the PMT single photon counter 4 and stops meter
Number, otherwise continues frequency-selecting and counting.
Specifically, PC computer or tablet computer can be used in host computer 1, can pass through between host computer 1 and control circuit 2
RS232 interface realizes electrical connection.
The synchronous control system of Rayleigh brillouin scattering signal acquisition provided by the invention and detection is based on above-mentioned Rayleigh cloth
In deep scattered signal acquisition and detection synchronisation control means, therefore, above-mentioned Rayleigh brillouin scattering signal acquisition and detection
The technical effect that synchronisation control means has, the acquisition of Rayleigh brillouin scattering signal is same as the synchronous control system of detection to be had
It is standby, it repeats no more again.
Specifically, fpga chip 21 selects the EP4CE15C8 of altera corp；From the serial ports of 21 input and output of fpga chip
Signal is divided into two-way, and all the way by ADM3101E chip drives RS232 interface, another way switchs to USB by FT232R chip and believes
Number driving USB interface.
Preferably, the control circuit 2 further includes digital analog converter 23, and the F-P scanning interferometer 3 passes through the digital-to-analogue
Converter 23 is electrically connected with the fpga chip 21；
The digital analog converter 23 is used to generate control voltage according to the control information of voltage；The F-P scanning interferometer
Instrument 3 receives the control voltage and carries out frequency-selecting to the Rayleigh brillouin scattering signal.
Specifically, digital analog converter 23 is used to generate the control voltage of F-P scanning interferometer 3, digital analog converter 23 is by DAC
Chip, voltage-reference and high voltage operational amplifier composition, wherein DAC chip model selects AD5721, voltage-reference type
Number select MAX6126, high voltage operational amplifier model select ADA4522.Control of the digital analog converter 23 to F-P scanning interferometer 3
Voltage processed is exported using bnc interface, exports 0~50V voltage.
Host computer 1 sends control command to fpga chip 21；Fpga chip 21 parses control voltage from control command
Information, control information of voltage include the information such as output area, synchronization time, interval time and the falling waveform for controlling voltage；
Fpga chip 21 meets the control voltage of control information of voltage requirement, F- according to control information of voltage control digital analog converter output
P scanning interferometer 3 carries out frequency-selecting under control of a control voltage, and control information of voltage includes synchronization time, therefore, in frequency-selecting
Between reach synchronization time when, fpga chip 21 control F-P scanning interferometer 3 stop frequency-selecting；Fpga chip 21 is to PMT single photon meter
The pulse signal that number device 4 inputs is counted, until synchronization time terminates, realizes F-P scanning interferometer 3 and single photon meter
The synchronously control of number device 4, ensure that the complete acquisition of spectral information.
Preferably, the host computer 1 is also used to obtain spectral information according to frequency-selecting result and count results, and to described
Spectral information carries out real-time display and storage.
Spectral information is shown and is stored, checks and obtains convenient for user.
Preferably, the control circuit 2 further includes memory 24, and the memory 24 is electrically connected with the fpga chip 21
It connects, the memory 24 is for caching the frequency-selecting result and count results.
Frequency-selecting result and count results are cached, data is avoided surprisingly to lose.
The above described specific embodiments of the present invention are not intended to limit the scope of the present invention..Any basis
Any other various changes and modifications that technical concept of the invention is made should be included in the guarantor of the claims in the present invention
It protects in range.
Claims (7)
1. a kind of synchronisation control means of Rayleigh brillouin scattering signal acquisition and detection, which comprises the following steps:
Step S1, control command is obtained from host computer, is parsed the control command and is obtained the control voltage of F-P scanning interferometer
Information, the control information of voltage includes synchronization time；
Step S2, the F-P scanning interferometer is controlled according to the control information of voltage to carry out Rayleigh brillouin scattering signal
Frequency-selecting is acquired, meanwhile, control PMT single photon counter carries out detection counting to the Rayleigh brillouin scattering signal；
Step S3, the gate time of the frequency-selecting time to the F-P scanning interferometer and the PMT single photon technique device carries out
Timing, and judge whether the frequency-selecting time and the gate time reach the synchronization time, if it is, described in control
F-P scanning interferometer stops frequency-selecting, and controls the PMT single photon counter and stop counting, otherwise continue frequency-selecting and
It counts.
2. the synchronisation control means of Rayleigh brillouin scattering signal acquisition and detection according to claim 1, feature exist
According to the control information of voltage control F-P scanning interferometer to Rayleigh brillouin scattering signal in the step S2
Frequency-selecting is acquired to specifically include:
Step S21, control voltage is generated according to the control information of voltage；
Step S22, the described F-P scanning interferometer receives the control voltage and selects the Rayleigh brillouin scattering signal
Frequently.
3. the synchronisation control means of Rayleigh brillouin scattering signal acquisition and detection according to claim 1, feature exist
In further including step S4, obtain spectral information according to frequency-selecting result and count results, and carry out to the spectral information real-time
Display and storage.
4. a kind of synchronous control system of Rayleigh brillouin scattering signal acquisition and detection, which is characterized in that including host computer, control
Circuit, F-P scanning interferometer and PMT single photon counter processed, the control circuit include fpga chip and crystal oscillating circuit；
The fpga chip and the upper mechatronics, and it is used to obtain control command from the host computer, described in parsing
Control command obtains the control information of voltage of F-P scanning interferometer, and the control information of voltage includes synchronization time；
The fpga chip is electrically connected with the F-P scanning interferometer and PMT single photon counter respectively, and is used for, according to
While the control information of voltage control F-P scanning interferometer is acquired frequency-selecting to Rayleigh brillouin scattering signal,
Control PMT single photon counter carries out detection counting to the Rayleigh brillouin scattering signal；
The crystal oscillating circuit is electrically connected with the fpga chip, and for frequency-selecting time of the F-P scanning interferometer and
The gate time of the PMT single photon technique device carries out timing；
The fpga chip is also used to judge whether the frequency-selecting time and the gate time reach the synchronization time, such as
Fruit is then to control the F-P scanning interferometer to stop frequency-selecting, and control the PMT single photon counter and stop counting, otherwise after
It is continuous to carry out frequency-selecting and counting.
5. the synchronous control system of Rayleigh brillouin scattering signal acquisition and detection according to claim 4, feature exist
In the control circuit further includes digital analog converter, and the F-P scanning interferometer passes through the digital analog converter and the FPGA
Chip electrical connection；
The digital analog converter is used to generate control voltage according to the control information of voltage；The F-P scanning interferometer receives
The control voltage simultaneously carries out frequency-selecting to the Rayleigh brillouin scattering signal.
6. the synchronous control system of Rayleigh brillouin scattering signal acquisition and detection according to claim 4, feature exist
In the host computer is also used to obtain spectral information according to frequency-selecting result and count results, and carries out to the spectral information
Real-time display and storage.
7. the synchronous control system of Rayleigh brillouin scattering signal acquisition and detection according to claim 4, feature exist
In the control circuit further includes memory, and the memory is electrically connected with the fpga chip, and the memory is used for institute
It states frequency-selecting result and count results is cached.
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