CN109029246A - Dynamic frequency scanning interfeerometry ranging system and distance measuring method based on optics frequency dividing locking phase gamma correction - Google Patents
Dynamic frequency scanning interfeerometry ranging system and distance measuring method based on optics frequency dividing locking phase gamma correction Download PDFInfo
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- G—PHYSICS
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- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B9/00—Measuring instruments characterised by the use of optical techniques
- G01B9/02—Interferometers
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
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Abstract
Based on the dynamic frequency scanning interfeerometry ranging system and distance measuring method of optics frequency dividing locking phase gamma correction, the present invention relates to dynamic frequency scanning interfeerometry ranging system and distance measuring methods.The purpose of the present invention is to solve in existing method by auxiliary interferometer provide nonlinear sampling clock correction frequency sweep interferometry signal it is nonlinear and meanwhile can cause vibration measuring signal generate it is non-linear, motion measurement signal spectrum is caused to broaden, signal-to-noise ratio decline, the problem of seriously affecting motion phase measurement accuracy, then influencing range accuracy.System includes frequency sweep interfeerometry ranging optical path, motion measurement optical path, phaselocked loop, No. 1 auxiliary interferometer, No. 2 auxiliary interferometers, external cavity laser, visible laser, single-frequency laser, No. 1 fiber coupler, data collecting card, No. 1 detector, No. 3 detectors.The present invention is for technical fields such as frequency sweep interferometry, FMCW laser radars.
Description
Technical field
The present invention relates to dynamic frequency scanning interfeerometry ranging system and distance measuring methods.
Background technique
Frequency sweep interferometry is low with transmission power, nothing obscures ranging, without guide rail and cooperative target, achievable high-resolution
Outstanding advantages of rate, thus be widely used in terms of high-precision absolute distance measurement, such as CW with frequency modulation laser thunder
It reaches, the fields such as optimal frequency domain meter, optical coherence tomography.The basic principle is that utilizing the measurement frequency sweep optical signal and quilt of transmitting
The difference on the frequency that generates by the time difference is surveyed between the sweep measurement optical signal of target reflection to determine target range, by being easier to
The signal frequency domain feature of processing reflects the distance parameter of target.The broadband sweep measurement light of High Linear it is available it is very high away from
High Resolution and range accuracy, but this measurement method is extremely sensitive to the movement of target, and displacement caused by being moved by target exists
Under the action of Doppler effect, causes finally to measure the error that distance generates several hundred to thousands of times, seriously affect range measurement essence
Degree, it is necessary to which it is compensated.Existing main method is using two frequency swept lasers along different directions frequency sweep or using one
Platform laser carries out triangular wave swept frequency.It is double that the former will result directly in expensive frequency swept laser cost, and the latter will be unable to pair
The too fast target of movement velocity is effectively compensated for, and therefore, studies a kind of frequency sweep interfering movement compensation method one of low cost
It is directly the research emphasis of this kind of measurement method.
It is existing to move synchronously measurement and compensation technique (Fig. 1) can be a kind of effective solution method based on superhet；
It is existing based on it is superhet move synchronously measurement and compensation technique include external cavity laser, No. 1 fiber coupler,
Auxiliary interferometer, No. 1 detector, data collecting card, No. 2 fiber couplers, No. 1 coupler, No. 2 couplers, No. 3 couplers,
Polarization keep beam splitter PBS, wavelength division multiplexer WDM, fiber end face, focus optical subsystem, quarter wave plate, balanced detector, can
Light-exposed laser, single-frequency laser, No. 3 fiber couplers, 1 bugle call optical modulator, 2 bugle call optical modulators, No. 4 fiber couplings
Device, No. 5 couplers, No. 4 couplers, No. 2 detectors；
Phase of the superheterodyne interferometer for utilizing single-frequency laser to be formed with alliteration optical modulator module in this method to target
On-line checking is carried out to motion information, amplification caused by Doppler effect in measurement result synchroballistic frequency sweep interferometry signal
Error term.The nonlinear sampling clock provided in this method by auxiliary interferometer is nonlinear in correction frequency sweep interferometry signal
Vibration measuring signal can be caused to generate simultaneously non-linear, motion measurement signal spectrum is caused to broaden, signal-to-noise ratio decline seriously affects movement
Phase measurement accuracy then influences range accuracy.
Summary of the invention
The purpose of the present invention is to solve the nonlinear sampling clocks provided in existing method by auxiliary interferometer in school
Positive frequency sweep interferometry signal is nonlinear while the generation of vibration measuring signal can be caused non-linear, causes motion measurement signal spectrum exhibition
The problem of width, signal-to-noise ratio decline, seriously affects motion phase measurement accuracy, then influences range accuracy, and propose to be based on optics
Divide the dynamic frequency scanning interfeerometry ranging system and distance measuring method of locking phase gamma correction.
Based on optics frequency dividing locking phase gamma correction dynamic frequency scanning interfeerometry ranging system include frequency sweep interfeerometry ranging optical path,
Motion measurement optical path, phase-locked loop module, No. 1 auxiliary interferometer, No. 2 auxiliary interferometers, external cavity laser, visible laser,
Single-frequency laser, No. 1 fiber coupler, data collecting card, No. 1 detector, No. 3 detectors；
Described No. 2 fiber couplers of frequency sweep interfeerometry ranging optical routing, No. 6 fiber couplers, No. 7 fiber couplers, No. 8 light
Fine coupler, polarization keep beam splitter PBS, wavelength division multiplexer WDM, focus optical subsystem, quarter wave plate and balanced detector
Composition；
No. 3 fiber couplers of the motion measurement optical routing, 1 bugle call optical modulator, 2 bugle call optical modulators, No. 4 optical fiber couplings
Clutch, No. 5 fiber couplers, No. 9 fiber couplers and No. 2 photodetectors are constituted；
The laser light incident of external cavity laser output to No. 1 fiber coupler carries out branch；
1 road light of No. 1 fiber coupler output is incident to No. 1 detector after No. 1 auxiliary interferometer, through No. 1 detector
Output signal is input to data collecting card afterwards；
External clock input signal of No. 1 auxiliary interferometer signal as data collecting card controls data collecting card to No. 1
Detector, No. 2 photodetectors, balanced detector signal sampled；
1 road light of No. 1 fiber coupler output is successively through No. 2 auxiliary interferometers and No. 3 detectors, after No. 3 detectors
Output signal be input to phase-locked loop module；
No. 2 auxiliary interferometers provide pll reference signal for phase-locked loop module；
98 road light of No. 1 fiber coupler output are incident to No. 2 fiber couplers and carry out branch；
The laser light incident of single-frequency laser output to No. 3 fiber couplers carry out branches, and the 99 of the output of No. 3 fiber couplers
1 bugle call optical modulator of Lu Guangjing is incident to No. 4 fiber couplers and carries out branch, and 1 road light of No. 3 fiber couplers output is through No. 2
Acousto-optic modulator is incident to No. 5 fiber couplers and carries out branch；
99 road light of 99 road light and the output of No. 4 fiber couplers that No. 2 fiber couplers export are closed through No. 6 fiber couplers
Be incident to after beam polarization keep beam splitter PBS the port A, through polarization keep beam splitter PBS the port B output light with can
The laser of laser output is seen after wavelength division multiplexer WDM multiplexing, successively through fiber end face, focusing optical subsystem and 1/4 wave
It is incident to measured target after piece, wavelength division multiplexer WDM is back to after measured target reflects, is demultiplexed through wavelength division multiplexer WDM
Light afterwards is incident to the port B that polarization keeps beam splitter PBS, then keeps the port C of beam splitter PBS to be emitted in polarization；
The 50 road light that the 1 road light and No. 5 fiber couplers of No. 2 fiber couplers output export through No. 7 fiber couplers into
Row closes beam, and the light and polarization after No. 7 fiber couplers conjunction beams keep the light of the port the C outgoing of beam splitter PBS through No. 8 optical fiber couplings
Clutch is incident to balanced detector after closing beam, and the signal of balanced detector output is incident to data collecting card；
50 road light of 1 road light and the output of No. 5 fiber couplers that No. 4 fiber couplers export are closed through No. 9 fiber couplers
No. 2 photodetectors are incident to after beam, the signal of No. 2 photodetectors output is incident to data collecting card and locking phase ring moulds respectively
Block；
The signal phase exported through phase-locked loop module, which synchronizes, is incident to 2 bugle call optical modulators, by changing 2 bugle call light modulations
The shift frequency amount of device, the signal for exporting No. 2 photodetectors are identical as phase-locked loop module reference signal phase.
The method detailed process of dynamic frequency scanning interfeerometry ranging system based on optics frequency dividing locking phase gamma correction are as follows:
Step 1: being detected through frequency sweep interfeerometry ranging optical-circuit balance detector defeated when measured target is dynamic object
Signal is i outm(k)；
What balanced detector detection arrived is i through motion measurement optical output signal1(t)；
The 1 bugle call optical modulator and 2 bugle call optical modulator difference frequency signals that No. 2 photodetectors detect are i2(t)；
Step 2: using No. 2 auxiliary interferometer output signals as pll reference signal Δ fPoint(t), by i1(t)、i2(t)
PGC demodulation is in pll reference signal Δ fPoint(t), then the motion measurement optical output signal that balanced detector detection arrives after locking phase
For i '1(t)；
The 1 bugle call optical modulator and 2 bugle call optical modulator difference frequency signals that No. 2 photodetectors detect after locking phase are i '2
(t)；
Step 3: the motion measurement optical output signal that balanced detector detection after locking phase is arrived is i '1(t) and after locking phase
The 1 bugle call optical modulator and 2 bugle call optical modulator difference frequency signals that No. 2 photodetectors detect are i '2(t) through external cavity type laser
After device exports optical frequency f (t) synchronized sampling, the motion measurement optical output signal and No. 2 photoelectricity that balanced detector detection arrives are visited
The 1 bugle call optical modulator and 2 bugle call optical modulator difference frequency signals that survey device detects are respectively i1(k) and i2(k)；
Step 4: signal i in extraction step onem(k), signal i in step 31(k)、i2(k) the phase changing capacity Δ in
Φm(k)、ΔΦ1(k)、ΔΦ2(k), by ΔΦ1(k)、ΔΦ2(k) the group delay time difference variation delta of corresponding measured target is obtained
τm(k), by Δ τm(k) ΔΦ is brought intom(k) the group delay time difference τ that corresponding measured target generates is obtained afterm0, according to Δ τm(k) and τm0
Obtain the distance R (k) of dynamic measured target；
In the step 1 when measured target is dynamic object, detected through frequency sweep interfeerometry ranging optical-circuit balance detector
Output signal im(k) are as follows:
Wherein, AmAmplitude for the signal detected through frequency sweep interfeerometry ranging optical-circuit balance detector, τ0For auxiliary interferometer
The delay inequality that 1 arm length difference generates, k is sampled point, τm0Indicate the group delay time difference that corresponding measured target generates；f0Indicate external cavity type
Laser starting output light frequency；Δτm(k) indicate that each sampled point corresponds to the group delay time difference variable quantity of measured target；
Balanced detector detection arrive through motion measurement optical output signal i1(t) are as follows:
The 1 bugle call optical modulator and 2 bugle call optical modulator difference frequency signal i that No. 2 photodetectors detect2(t) are as follows:
i2(t)=A2cos[2π(fAOM1-fAOM2) t]=A2cos[2πΔfAOMt] (3)
Wherein, A1Indicate the motion measurement optical output signal i that balanced detector detection arrives1(t) amplitude, A2Indicate No. 2
The 1 bugle call optical modulator and 2 bugle call optical modulator difference frequency signal i that photodetector detects2(t) amplitude, t are sampled point,
fAOM1Indicate the shift frequency amount of 1 bugle call optical modulator, fAOM2Indicate the shift frequency amount of 2 bugle call optical modulators, Δ fAOMIndicate 1 bugle call light tune
Device processed and 2 bugle call optical modulator shift frequencies are poor, f0The output light frequency of ' expression single-frequency laser；τm(t) corresponding tested mesh is indicated
Mark the group delay time difference generated；Δτm(t) the group delay time difference variable quantity of corresponding measured target is indicated；
Using No. 2 auxiliary interferometer output signals as pll reference signal Δ f in the step 2Point(t), by i1(t)、i2
(t) PGC demodulation is in pll reference signal Δ fPoint(t), then the motion measurement optical output that balanced detector detection arrives after locking phase
Signal is i '1(t)；
The 1 bugle call optical modulator and 2 bugle call optical modulator difference frequency signals that No. 2 photodetectors detect after locking phase are i '2
(t)；
Detailed process are as follows:
No. 2 auxiliary interferometer output signals are as pll reference signal Δ fPoint(t), then have:
Wherein, Δ f (t) is the equal optical frequency intervals of No. 1 auxiliary interferometer output；M is that No. 2 auxiliary interferometers are auxiliary compared to No. 1
The frequency dividing multiple for helping interferometer, by the frequency shift amount f for changing 2 bugle call optical modulatorsAOM2, by formula (2), the 2 π Δ of phase of (3)
fAOMT is locked in pll reference signal Δ fPoint(t), i.e.,
Wherein ΔΦlockFor i ' after locking phase1(t) fixed skew part, the then fortune that balanced detector detection arrives after locking phase
Dynamic optical path output signal are as follows:
The 1 bugle call optical modulator and 2 bugle call optical modulator difference frequency signal i ' that No. 2 photodetectors detect after locking phase2(t)
Are as follows:
The invention has the benefit that
The present invention proposes that this method is in original based on the dynamic frequency scanning interfeerometry ranging method of optics frequency dividing locking phase gamma correction
On the basis of having auxiliary interferometer, by another auxiliary interferometer and phase-locked loop module by the non-linear previously-introduced vibration measuring of frequency sweep
Signal realizes the active chirp of vibration measuring signal, enables vibration measuring signal have identical with frequency sweep interfeerometry ranging signal non-linear, thus through
After former auxiliary interferometer sampling, realizes distance measuring signal and the non-linear synchronous correction of vibration measuring signal, solve vibration measuring in existing method
Signal because distance measuring signal gamma correction leads to not accurately extract vibration phase information, signal-to-noise ratio decline the problem of, it can be achieved that
Remote noncooperative target measurement.
Realize that actively introducing is identical with frequency sweep interfeerometry ranging signal non-linear in advance in motion measurement signal, then through auxiliary
After helping the optical frequencies Time-Domain Nonlinear such as interferometer 1 to sample, realization gamma correction synchronous with frequency sweep interfeerometry ranging signal, to avoid
It is non-linear that existing method motion measurement signal introduces frequency sweep after the sampling of the optical frequencies Time-Domain Nonlinear such as auxiliary interferometer 1, causes
Motion measurement signal spectrum broadening, signal-to-noise ratio decline, seriously affects motion phase measurement accuracy, then influences range accuracy.
It, can caused by the present invention moves in eliminating frequency sweep interfeerometry ranging signal because of measured target while Doppler effect
Vibration measuring optical path signal signal-to-noise ratio, better signal waveform are effectively improved, lesser metamorphopsic distortion, stronger backward energy can be real
Incumbent meaning noncooperative target measurement.Meanwhile having many advantages, such as that structure is simple, measuring speed is fast, on line emendation, it is at low cost.
Fig. 3 is the simple harmonic oscillation of 5 μm of frequency 10Hz amplitude, the at the uniform velocity vibration that Fig. 4 is 100mm/ seconds.As it can be seen that non-linear school
Because optical frequency sampling introducing is non-linear before just, motion measurement signal spectrum is broadened, and it is non-linear serious with optical frequency to broaden degree
Degree is related, and when it is 3% that optical frequency is non-linear, motion measurement signal has been lower than -40dB, after active chirp gamma correction,
Motion measurement signal boost is -13dB and 0dB or so (without spectral line spectral line), and Signal-to-Noise is promoted obviously, demonstrated
The method of the present invention correction optical frequency synchronizes nonlinear validity, so as to ensure the method for the present invention to the phase of non-cooperative moving targets
Position measurement accuracy.
Detailed description of the invention
Fig. 1 is existing method light path schematic diagram；
Fig. 2 is the method for the present invention light path schematic diagram.
Fig. 3 is comparison diagram, vibration before and after the synchronous gamma correction of measured target simple harmonic motion measuring signal optical frequency at 10m distance
Dynamic amplitude is 5 μm, frequency 10Hz；
Fig. 4 is the synchronous gamma correction front and back comparison diagram of measured target uniform motion measuring signal optical frequency at 10m distance, even
Speed movement: 100mm/ seconds.
Specific embodiment
It is surveyed specific embodiment 1: the dynamic frequency scanning based on optics frequency dividing locking phase gamma correction of present embodiment is interfered
Away from system, as shown in Fig. 2, the dynamic frequency scanning interfeerometry ranging system based on optics frequency dividing locking phase gamma correction, it is characterised in that:
The system comprises frequency sweep interfeerometry ranging optical path, motion measurement optical path, the auxiliary interferometer 2,2 of phase-locked loop module 24,1 auxiliary
Interferometer 26, external cavity laser 1, visible laser 5,16, No. 1 fiber couplers 15 of single-frequency laser, data collecting card 4,1
Number 3, No. 3 detectors 25 of detector；
The fiber coupler 7,7 of No. 2 fiber couplers of frequency sweep interfeerometry ranging optical routing 6,6 fiber coupler 8,8
Number fiber coupler 10, polarization keep beam splitter PBS9, wavelength division multiplexer WDM11, focus optical subsystem 12 (camera lens,
Represented on figure with convex lens), the Mach-Zehnder interferometer that forms of quarter wave plate 13 and balanced detector 14；
No. 3 fiber couplers 17 of the motion measurement optical routing, 1 bugle call optical modulator 18,2 bugle call optical modulator 19,4
The superhet that fiber coupler 20, No. 5 fiber couplers, 21, No. 9 fiber couplers 22 and No. 2 photodetectors 23 are constituted is dry
Interferometer；
The laser light incident that external cavity laser 1 exports to No. 1 fiber coupler 15 carries out branch；
1 road light of No. 1 fiber coupler 15 output is incident to No. 1 detector 3 after No. 1 auxiliary interferometer 2, visits through No. 1
Output signal is input to data collecting card 4 after surveying device 3；
The phase-locked loop module is made of phase discriminator, loop filter and the equivalent voltage controlled oscillator of superheterodyne interferometer；
Phase-locked loop module uses existing chip, chip model HMC1031；
External clock input signal of No. 12 signal of auxiliary interferometer as data collecting card 4, control data collecting card 4 are right
3, No. 2 photodetectors 23 of No. 1 detector, balanced detector 14 signal sampled；
1 road light of No. 1 fiber coupler 15 output successively through No. 2 auxiliary interferometer 26 and No. 3 detectors 25, is visited through No. 3
Output signal after surveying device 25 is input to phase-locked loop module 24；
No. 2 auxiliary interferometers 26 are that phase-locked loop module 24 provides pll reference signal；
98 road light of No. 1 fiber coupler 15 output are incident to No. 2 fiber couplers 6 and carry out branch；
The laser light incident that single-frequency laser 16 exports to No. 3 fiber couplers 17 carry out branch, and No. 3 fiber couplers 17 are defeated
99 road light of Chu is incident to No. 4 fiber couplers 20 through 1 bugle call optical modulator 18 and carries out branch, and No. 3 fiber couplers 17 export
1 road light be incident to No. 5 fiber couplers 21 through 2 bugle call optical modulators 19 and carry out branches；
99 road light of 99 road light and the output of No. 4 fiber couplers 20 that No. 2 fiber couplers 6 export are through No. 6 fiber couplings
Device 7 is incident to the port A that polarization keeps beam splitter PBS9 after closing beam, keeps the port B of beam splitter PBS9 to export through polarization
Light and visible laser 5 export laser through wavelength division multiplexer WDM11 multiplexing after, successively through fiber end face, focus optics
It is incident to measured target after system 12 and quarter wave plate 13, wavelength division multiplexer WDM11 is back to after measured target reflects, through wave
Light after division multiplexer WDM11 demultiplexing is incident to the port B that polarization keeps beam splitter PBS9, then keeps beam splitter in polarization
The port C of PBS9 is emitted；
50 road light of 1 road light and the output of No. 5 fiber couplers 21 that No. 2 fiber couplers 6 export are through No. 7 fiber couplers
8 carry out conjunction beam, and the light and polarization after No. 7 conjunction beams of fiber couplers 8 keep the light of the port the C outgoing of beam splitter PBS9 through No. 8
Fiber coupler 10 is incident to balanced detector 14 after closing beam, and the signal that balanced detector 14 exports is incident to data collecting card 4；
50 road light of 1 road light and the output of No. 5 fiber couplers 21 that No. 4 fiber couplers 20 export are through No. 9 fiber couplings
The signal that the output of 23, No. 2 photodetectors 23 of No. 2 photodetectors is incident to after the conjunction beam of device 22 is incident to data collecting card respectively
4 and phase-locked loop module 24；
The signal phase exported through phase-locked loop module 24, which synchronizes, is incident to 2 bugle call optical modulators 19, by changing 2 bugle call light
The shift frequency amount of modulator 19, the signal for exporting No. 2 photodetectors 23 are identical as 24 reference signal phase of phase-locked loop module.
Realize that actively introducing is identical with frequency sweep interfeerometry ranging signal non-linear in advance in motion measurement signal, then through auxiliary
After helping the optical frequencies Time-Domain Nonlinear such as interferometer 1 to sample, realization gamma correction synchronous with frequency sweep interfeerometry ranging signal, to avoid
It is non-linear that existing method motion measurement signal introduces frequency sweep after the sampling of the optical frequencies Time-Domain Nonlinear such as auxiliary interferometer 1, causes
Motion measurement signal spectrum broadening, signal-to-noise ratio decline, seriously affects motion phase measurement accuracy, then influences range accuracy.
Frequency sweep interfeerometry ranging optical path realizes that the absolute distance measurement of whole device, motion measurement optical path synchro measure are tested mesh
Target motion phase, compensates distance measuring signal, to eliminate influence of the target movement to measurement result；
Sampling clock of the auxiliary interferometer 1 as entire measuring system provides the Time-Domain Nonlinear sampling of equal optical frequency intervals,
Auxiliary interferometer 2 provides pll reference signal for phase-locked loop module, by changing the shift frequency amount of 2 bugle call optical modulators, will move
Two acousto-optic modulator phase differences of optical path are locked in reference signal phase, realize the active in advance in motion measurement signal
It introduces identical with frequency sweep interfeerometry ranging signal non-linear, then after the optical frequencies Time-Domain Nonlinear such as auxiliary interferometer 1 samples, and sweeps
Frequency interfeerometry ranging signal is synchronous to realize gamma correction, so as to avoid existing method motion measurement signal through auxiliary interferometer 1
Etc. optical frequencies Time-Domain Nonlinear sampling after introduce frequency sweep it is non-linear, cause motion measurement signal spectrum broaden, signal-to-noise ratio decline, seriously
Motion phase measurement accuracy is influenced, range accuracy is then influenced.
It, can caused by the present invention moves in eliminating frequency sweep interfeerometry ranging signal because of measured target while Doppler effect
Vibration measuring optical path signal signal-to-noise ratio, better signal waveform are effectively improved, lesser metamorphopsic distortion, stronger backward energy can be real
Incumbent meaning noncooperative target measurement.Meanwhile having many advantages, such as that structure is simple, measuring speed is fast, on line emendation, it is at low cost.
Acousto-optic modulator can generate acousto-optic frequency translation effect, which is a kind of laser diffraction effect, when having longitudinal wave characteristic
Sound wave when propagating in the medium, the refractive index of medium can generating period variation, the cyclically-varying of refractive index enables medium can
To be equivalent to an acoustic grating.By the acoustic grating optical diffraction phenomenon will occur for laser, the frequency of diffraction light, intensity,
The relating to parameters in direction and equivalent acoustic grating.According to the difference of incident light glancing angle, which shows as Raman-Nai Si
(Raman-Nath) diffraction and Prague (Bragg) diffraction.The offset of light frequency, benefit are realized in the present invention using acousto-optic modulator
It is Bragg diffraction type acousto-optic modulation principle, when incidence angle is Bragg angle, diffracted light intensity reaches maximum, is spreading out
The offset of laser frequency is realized during penetrating, the frequency of offset is identical as the frequency of ultrasonic wave.In general acousto-optic modulation
In device, the frequency of ultrasonic wave is determined by acoustooptic modulator driver signal frequency, therefore, by adjust driving signal frequency and
Intensity can carry out accurate control to the light intensity of optical frequency offset and shift frequency diffraction light.
In order to which the Doppler effect for overcoming measured target relative motion to introduce influences, the Doppler based on alliteration optical modulator
Effect correction method structure such as Fig. 1, frequency sweep interfeerometry ranging and the vibration measuring of alliteration optical modulator are using line structure altogether, it can be achieved that same pacing
Measure measured target.
Specific embodiment 2: the present embodiment is different from the first embodiment in that: No. 5 fiber couplers
21, No. 6 10, No. 9 fiber couplers 22 of fiber coupler of fiber coupler 8,8 of fiber coupler 7,7 are 3dB coupling
Device.Three-dB coupler is exactly 50:50 shunting coupler.
Other steps and parameter are same as the specific embodiment one.
Specific embodiment 3: the present embodiment is different from the first and the second embodiment in that: No. 1 fiber coupling
Device 15 is 1:98:1 branch fiber coupler.
Other steps and parameter are the same as one or two specific embodiments.
Specific embodiment 4: unlike one of present embodiment and specific embodiment one to three: No. 2 optical fiber
The fiber coupler 20 of fiber coupler 17,4 of coupler 6,3 is 99:1 branch fiber coupler.
Other steps and parameter are identical as one of specific embodiment one to three.
It is surveyed specific embodiment 5: the dynamic frequency scanning based on optics frequency dividing locking phase gamma correction of present embodiment is interfered
Distance measuring method detailed process away from system are as follows:
Step 1: being detected when measured target is dynamic object through frequency sweep interfeerometry ranging optical-circuit balance detector 14
Output signal is im(k)；
What balanced detector 14 detected is i through motion measurement optical output signal1(t)；
1 bugle call of bugle call optical modulator 18 and 2 optical modulator, 19 difference frequency signal that No. 2 photodetectors 23 detect is i2
(t)；
Step 2: using No. 2 26 output signals of auxiliary interferometer as pll reference signal Δ fPoint(t), by i1(t)、i2(t)
PGC demodulation in pll reference signal Δ fPoint(t), then the motion measurement optical output that balanced detector 14 detects after locking phase
Signal is i '1(t)；
1 bugle call of bugle call optical modulator 18 and 2 optical modulator, 19 difference frequency signal that No. 2 photodetectors 23 detect after locking phase
For i '2(t)；
Step 3: the motion measurement optical output signal that balanced detector 14 after locking phase is detected is i '1(t) and locking phase
1 bugle call of bugle call optical modulator 18 and 2 optical modulator, 19 difference frequency signal that No. 2 photodetectors 23 detect afterwards is i '2(t) through outer
After cavate laser 1 exports optical frequency f (t) synchronized sampling, motion measurement optical output signal that balanced detector 14 detects with
And 1 bugle call of bugle call optical modulator 18 and 2 optical modulator, 19 difference frequency signal that No. 2 photodetectors 23 detect is respectively i1(k)
And i2(k)；
Step 4: signal i in extraction step onem(k), signal i in step 31(k)、i2(k) the phase changing capacity Δ in
Φm(k)、ΔΦ1(k)、ΔΦ2(k), by ΔΦ1(k)、ΔΦ2(k) the group delay time difference variation delta of corresponding measured target is obtained
τm(k), by Δ τm(k) ΔΦ is brought intom(k) the group delay time difference τ that corresponding measured target generates is obtained afterm0, according to Δ τm(k) and τm0
Obtain the distance R (k) of dynamic measured target；
It is by formula (1) it is found that flat through frequency sweep interfeerometry ranging optical path in the step 1 when measured target is dynamic object
The output signal that weighing apparatus detector 14 detects are as follows:
Wherein, AmAmplitude for the signal detected through frequency sweep interfeerometry ranging optical-circuit balance detector 14, τ0For auxiliary interference
The delay inequality that 1 arm length difference of instrument generates, k is sampled point, τm0It indicates the group delay time difference that corresponding measured target generates, contains tested mesh
It is marked on the static absolute distance information of measurement initial time；f0Indicate starting output light when external cavity laser 1 is tuned
Frequency；Δτm(k) the group delay time difference variable quantity for indicating corresponding measured target, is the function of sampled point k, is sweeping containing measured target
In the frequency interferometry period, distance change amount information of any time with respect to initial time；
Formula (1) phase first itemInclude measured target absolute distance information, 2 π f of Section 20Δτm(k)
And Section 3Include measured target motion information, referred to as motion phase item, 2 π f of Section 40τm0For constant term.
As it can be seen that measuring signal is no longer more than the ideal about optical frequency sampled point index value k due to the presence of motion phase item
String signal can not obtain the narrow band spectrum comprising ranging information, and due to the frequency f of laser0It is very high, it is much higher than laser frequency
Variation delta f (k)=k/ τ0Even if the change in optical path length for causing measured target only small in measurement process, measuring signal
It is influenced to also bring along serious video stretching by phase Section 2, i.e., so-called Doppler effect, the frequency sweep interference thus introduced
Laser ranging error is hundreds and thousands of times of this change in optical path length amount.
Mach-Zehnder interferometer is cried in this way from structure, and auxiliary interferometer 1 and 2 is all Mach-pool Deccan from structure
Interferometer；
Balanced detector 14 detect through motion measurement optical output signal i1(t) are as follows:
1 bugle call of bugle call optical modulator 18 and 2 optical modulator, the 19 difference frequency signal i that No. 2 photodetectors 23 detect2(t)
Are as follows:
i2(t)=A2cos[2π(fAOM1-fAOM2) t]=A2cos[2πΔfAOMt] (3)
Wherein, A1Indicate the motion measurement optical output signal i that balanced detector 14 detects1(t) amplitude, A2Indicate 2
1 bugle call of bugle call optical modulator 18 and 2 optical modulator, the 19 difference frequency signal i that number photodetector 23 detects2(t) amplitude, t are
Sampled point, fAOM1Indicate the shift frequency amount of 1 bugle call optical modulator 18, fAOM2Indicate the shift frequency amount of 2 bugle call optical modulators 19, Δ fAOMTable
Show that 1 bugle call of bugle call optical modulator 18 and 2 19 shift frequencies of optical modulator are poor, f0The output light frequency of ' expression single-frequency laser 16；τm(t)
Indicate the group delay time difference that corresponding measured target generates, the static absolute distance containing measured target in measurement initial time is believed
Breath；Δτm(t) the group delay time difference variable quantity for indicating corresponding measured target, is the function of sampled point t, containing measured target in frequency sweep
In the interferometry period, distance change amount information of any time with respect to initial time；
It is the time in the physical meaning of t, but actual experiment clock capture card can not all adopt the data of institute's having time, only
Can the discrete number of accepting and believing of Fixed Time Interval, so and sampled point；
Existing method is by i1(t) and i2(t) after external cavity laser exports optical frequency f (t) synchronized sampling, balanced detector
The 14 motion measurement optical output signals detected are i1(k), the 1 bugle call optical modulator 18 that No. 2 photodetectors 23 detect
It is i with 2 bugle call optical modulator, 19 difference frequency signal2(k) it is respectively as follows:
i1(k)=A1cos[2πΔfAOMt(k)+2π(f0′+fAOM1)τm0+2π(f0′+fAOM1)Δτm(k)] (4)
i2(k)=A2cos[2π(fAOM1-fAOM2) t (k)]=A2cos[2πΔfAOMt(k)] (5)
Wherein, t (k) indicates that sampled point t and optical frequency f (t) (are equal to unknown non-thread between optical frequency sampled point index value k)
Property functional relation；Contain non-linear, signal spectrum broadening, signal-to-noise ratio decline.K expression sampled point draws value；
The physical meaning of k is equal optical frequency intervals as sampled point, and k-th sampled point is exactly to be spaced K to wait optical frequency intervals,
Also draw value as sampled point.
The optical frequency f (t) is changed over time by what external cavity laser 1 exported, f (t)=f0+ Δ f (t), every change
Change an equal frequency interval Δ f (t), sampling is primary, this τ of equal frequency interval Δ f (t)=1/0, so, k-th
Sampled point is exactly Δ f (k)=k/ τ0, all become to be illustrated with k；
Δ f (t) is the equal optical frequency intervals that No. 1 auxiliary interferometer 2 exports；The signal of all formula can be made with optical frequency f (t)
It is sampled for light clock；
Due to tunable laser output optical frequency contain Time-Domain Nonlinear, to containing identical nonlinear distance measuring signal into
While row correction, the motion measurement signal for being free of the Time-Domain Nonlinear originally is but caused to produce non-linear.As formula (4),
(5) shown in, because of the nonlinear function between time t and optical frequency f (t), signal i2It is the ideal cosine function of time t,
It but is not the ideal cosine function of optical frequency f (t).Therefore motion measurement signal i is caused with optical frequency f (t) synchronized sampling1(k) go out
Existing video stretching, signal-to-noise ratio decline, then influences phase delta Φ1(k) extraction accuracy cannot achieve accurate compensation.
Using No. 2 26 output signals of auxiliary interferometer as pll reference signal Δ f in the step 2Point(t), by i1(t)、
i2(t) PGC demodulation is in pll reference signal Δ fPoint(t), then the motion measurement optical path that balanced detector 14 detects after locking phase
Output signal is i '1(t)；
1 bugle call of bugle call optical modulator 18 and 2 optical modulator, 19 difference frequency signal that No. 2 photodetectors 23 detect after locking phase
For i '2(t)；
Detailed process are as follows:
To overcome the problems, such as this, auxiliary interferometer 2 is exported and is believed by the frequency shift amount of 2 bugle call optical modulators of change by the present invention
Number locking phase is carried out with two acousto-optic modulator difference frequency signals, as shown in phantom in Figure 2, introduces motion measurement signal actively in advance same
The frequency sweep Time-Domain Nonlinear of sample causes motion measurement signal active chirp, then through tunable laser output optical frequency f (t) sampling
It can get the motion measurement signal with ideal cosine function form afterwards, surveyed to eliminate because optical frequency synchronized sampling bring moves
It is non-linear to measure signal, avoids it that the broadening of motion measurement signal spectrum is caused then signal-to-noise ratio to be caused to decline, it is ensured that motion phase is real
Existing extracted with high accuracy and compensation.This method cardinal principle is described below:
No. 2 26 output signals of auxiliary interferometer are as pll reference signal Δ fPoint(t), then have:
Wherein, Δ f (t) is the equal optical frequency intervals that No. 1 auxiliary interferometer 2 exports；M is that No. 2 auxiliary interferometers 26 compare No. 1
The frequency dividing multiple of auxiliary interferometer 2, by the frequency shift amount f for changing 2 bugle call optical modulators 19AOM2, by formula (2), the phase of (3)
2πΔfAOMT is locked in pll reference signal Δ fPoint(t), i.e.,
Wherein ΔΦlockFor i ' after locking phase1(t) fixed skew part, then balanced detector 14 detects after locking phase
Motion measurement optical output signal are as follows:
1 bugle call of bugle call optical modulator 18 and 2 optical modulator, 19 difference frequency signal that No. 2 photodetectors 23 detect after locking phase
i′2(t) are as follows:
Specific embodiment 6: present embodiment is unlike specific embodiment five: by locking phase in the step 3
The motion measurement optical output signal that balanced detector 14 detects afterwards is i '1(t) and after locking phase No. 2 photodetectors 23 detect
1 bugle call of bugle call optical modulator 18 and 2 optical modulator, 19 difference frequency signal arrived is i '2(t) optical frequency f is exported through external cavity laser 1
(t) after synchronized sampling, the motion measurement optical output signal and No. 2 photodetectors 23 that balanced detector 14 detects are detected
To 1 bugle call of bugle call optical modulator 18 and 2 optical modulator, 19 difference frequency signal be respectively i1(k) and i2(k)；Detailed process are as follows:
I ' in formula (8)1(t) and formula (9) in i '2(t) it synchronizes and adopts through the output of external cavity laser 1 optical frequency f (t)
After sample, motion measurement optical output signal i that balanced detector 14 detects1(k) and No. 2 photodetectors 23 detect
1 bugle call of bugle call optical modulator 18 and 2 optical modulator, 19 difference frequency signal i2(k) it is respectively as follows:
Compared with not using the optical frequency before the synchronous gamma correction of active chirp optical frequency to move synchronously measuring signal, time t
Nonlinear terms between optical frequency f (t) become the linear term using k as variable, so as to avoid motion measurement signal i1(k) frequency spectrum
It broadens, signal-to-noise ratio decline can provide effective guarantee for the motion phase compensation precision of dynamic frequency scanning ranging.
Originally such as the vibration measuring signal of formula (4) (5), become the vibration measuring signal such as formula (10) (11), without at any time
Non-linear effects, signal spectrum do not broaden, and signal-to-noise ratio improves；Originally the expression formula of formula (4) (5) has been described that: t
(k) indicate that time t and optical frequency f (t) (are equal to nonlinear function unknown between optical frequency sampled point index value k)；Contain
It is non-linear, signal spectrum broadening, signal-to-noise ratio decline.
Other steps and parameter are identical as specific embodiment five.
Specific embodiment 7: present embodiment is unlike specific embodiment five or six: being mentioned in the step 4
Take signal i in step 1m(k), signal i in step 31(k)、i2(k) the phase changing capacity ΔΦ inm(k)、ΔΦ1(k)、Δ
Φ2(k), by ΔΦ1(k)、ΔΦ2(k) the group delay time difference variation delta τ of corresponding measured target is obtainedm(k), by Δ τm(k) it brings into
ΔΦm(k) the group delay time difference τ that corresponding measured target generates is obtained afterm0, according to Δ τm(k) and τm0Obtain dynamic measured target
Distance R (k)；Detailed process are as follows:
Extract formula (1), (10), the phase changing capacity ΔΦ in (11) signalm(k)、ΔΦ1(k)、ΔΦ2(k), respectively
Are as follows:
It can be obtained by formula (13), (14) simultaneous:
It is obtained after bringing formula (15) into formula (12):
The then distance of dynamic measured target are as follows:
N in formulaairFor air refraction, c is the light velocity.
As it can be seen that after this method is by being separated the error phase that target movement introduces in frequency sweep interfeerometry ranging signal,
Motion measurement optical path is introduced on the basis of static sweep frequency interfeerometry ranging optical path, it is non-based on the synchronous frequency sweep for carrying out distance measuring signal of optical frequency
Linearity correction and dynamic error compensation eliminate dynamic measurement error source, it can be achieved that based on single tunable sharp from measurement mechanism
Light device can be used for the dynamic frequency scanning interference laser absolute distance measurement of noncooperative target.
Other steps and parameter are identical as specific embodiment five or six.
Beneficial effects of the present invention are verified using following embodiment:
Embodiment one:
The present embodiment is specifically to be prepared according to the following steps:
To show influence of the optical frequency synchronized sampling to target motion phase measuring signal, while verifying the quasi- proposition of the present invention
It is real to have carried out emulation to this method for the feasibility of the synchronous non-linear correction method of target motion measurement signal active chirp optical frequency
It tests.The sweep rate of laser is 100nm/s, and auxiliary interferometer optical path difference is 220m, uses points for 2 × 106It (is equivalent to sharp
Light device swept frequency range is 2.73THz), measured target motion phase optical frequency synchro measure signal such as Fig. 3, Fig. 4 institute at 10m distance
Show.
Fig. 3 is the simple harmonic oscillation of 5 μm of frequency 10Hz amplitude, the at the uniform velocity vibration that Fig. 4 is 100mm/ seconds.As it can be seen that non-linear school
Because optical frequency sampling introducing is non-linear before just, motion measurement signal spectrum is broadened, and it is non-linear serious with optical frequency to broaden degree
Degree is related, and when it is 3% that optical frequency is non-linear, motion measurement signal has been lower than -40dB, after active chirp gamma correction,
Motion measurement signal boost is -13dB and 0dB or so (without spectral line spectral line), and Signal-to-Noise is promoted obviously, demonstrated
The method of the present invention correction optical frequency synchronizes nonlinear validity, so as to ensure the method for the present invention to the phase of non-cooperative moving targets
Position measurement accuracy.
The present invention can also have other various embodiments, without deviating from the spirit and substance of the present invention, this field
Technical staff makes various corresponding changes and modifications in accordance with the present invention, but these corresponding changes and modifications all should belong to
The protection scope of the appended claims of the present invention.
Claims (7)
1. the dynamic frequency scanning interfeerometry ranging system based on optics frequency dividing locking phase gamma correction, it is characterised in that: the system packet
Include frequency sweep interfeerometry ranging optical path, motion measurement optical path, phase-locked loop module (24), No. 1 auxiliary interferometer (2), No. 2 auxiliary interferometers
(26), external cavity laser (1), visible laser (5), single-frequency laser (16), No. 1 fiber coupler (15), data acquisition
Block (4), No. 1 detector (3), No. 3 detectors (25)；
No. 2 fiber couplers (6) of the frequency sweep interfeerometry ranging optical routing, No. 6 fiber couplers (7), No. 7 fiber couplers (8),
No. 8 fiber couplers (10), polarization keep beam splitter PBS (9), wavelength division multiplexer WDM (11), focus optical subsystem (12),
Quarter wave plate (13) and balanced detector (14) composition；
No. 3 fiber couplers (17) of the motion measurement optical routing, 1 bugle call optical modulator (18), 2 bugle call optical modulators (19), 4
Number fiber coupler (20), No. 5 fiber couplers (21), No. 9 fiber couplers (22) and No. 2 photodetector (23) structures
At；
The laser light incident of external cavity laser (1) output to No. 1 fiber coupler (15) carries out branch；
1 road light of No. 1 fiber coupler (15) output is incident to No. 1 detector (3) after No. 1 auxiliary interferometer (2), through No. 1
Output signal is input to data collecting card (4) to detector (3) afterwards；
External clock input signal of No. 1 auxiliary interferometer (2) signal as data collecting card (4) controls data collecting card (4)
The signal of No. 1 detector (3), No. 2 photodetectors (23), balanced detector (14) is sampled；
1 road light of No. 1 fiber coupler (15) output is successively through No. 2 auxiliary interferometers (26) and No. 3 detectors (25), through No. 3
Output signal after detector (25) is input to phase-locked loop module (24)；
No. 2 auxiliary interferometers (26) are that phase-locked loop module (24) provide pll reference signal；
98 road light of No. 1 fiber coupler (15) output are incident to No. 2 fiber couplers (6) and carry out branch；
The laser light incident of single-frequency laser (16) output to No. 3 fiber couplers (17) carry out branch, No. 3 fiber couplers (17)
99 road light of output are incident to No. 4 fiber couplers (20) through 1 bugle call optical modulator (18) and carry out branch, No. 3 fiber couplers
(17) the 1 road light exported is incident to No. 5 fiber couplers (21) through 2 bugle call optical modulators (19) and carries out branch；
99 road light of 99 road light and the output of No. 4 fiber couplers (20) that No. 2 fiber couplers (6) export are through No. 6 fiber couplings
Device (7) is incident to the port A that polarization keeps beam splitter PBS (9) after closing beam, and No. B end of beam splitter PBS (9) is kept through polarization
Mouthful output light and visible laser (5) output laser through wavelength division multiplexer WDM (11) multiplexing after, successively through fiber end face,
It is incident to measured target after focusing optical subsystem (12) and quarter wave plate (13), it is multiple that wavelength-division is back to after measured target reflects
With device WDM (11), the light after wavelength division multiplexer WDM (11) demultiplexing is incident to No. B end that polarization keeps beam splitter PBS (9)
Mouthful, then keep the port C of beam splitter PBS (9) to be emitted in polarization；
50 road light of 1 road light and the output of No. 5 fiber couplers (21) that No. 2 fiber couplers (6) export are through No. 7 fiber couplers
(8) conjunction beam is carried out, No. 7 fiber couplers (8) close the light and the light of the port the C outgoing of polarization holding beam splitter PBS (9) after beam
It is incident to balanced detector (14) after No. 8 fiber couplers (10) close beam, the signal of balanced detector (14) output is incident to
Data collecting card (4)；
50 road light of 1 road light and the output of No. 5 fiber couplers (21) that No. 4 fiber couplers (20) export are through No. 9 fiber couplings
Device (22) is incident to No. 2 photodetectors (23) after closing beam, and the signal of No. 2 photodetectors (23) output is incident to data respectively
Capture card (4) and phase-locked loop module (24)；
The signal phase exported through phase-locked loop module (24), which synchronizes, is incident to 2 bugle call optical modulators (19), by changing 2 bugle call light
The shift frequency amount of modulator (19), the signal for exporting No. 2 photodetectors (23) and phase-locked loop module (24) reference signal phase
It is identical.
2. the dynamic frequency scanning interfeerometry ranging system according to claim 1 based on optics frequency dividing locking phase gamma correction, special
Sign is: No. 5 fiber couplers (21), No. 6 fiber couplers (7), No. 7 fiber couplers (8), No. 8 fiber couplers
(10), No. 9 fiber couplers (22) are three-dB coupler.
3. the dynamic frequency scanning interfeerometry ranging system according to claim 2 based on optics frequency dividing locking phase gamma correction, special
Sign is: No. 1 fiber coupler (15) is 1:98:1 branch fiber coupler.
4. the dynamic frequency scanning interfeerometry ranging system according to claim 3 based on optics frequency dividing locking phase gamma correction, special
Sign is: No. 2 fiber couplers (6), No. 3 fiber couplers (17), No. 4 fiber couplers (20) are 99:1 branch light
Fine coupler.
5. the side based on the dynamic frequency scanning interfeerometry ranging system based on optics frequency dividing locking phase gamma correction described in claim 1
Method, it is characterised in that: the method detailed process are as follows:
Step 1: being detected through frequency sweep interfeerometry ranging optical-circuit balance detector (14) defeated when measured target is dynamic object
Signal is i outm(k)；
What balanced detector (14) detected is i through motion measurement optical output signal1(t)；
The 1 bugle call optical modulator (18) and 2 bugle call optical modulator (19) difference frequency signals that No. 2 photodetectors (23) are detected are i2
(t)；
Step 2: using No. 2 auxiliary interferometer (26) output signals as pll reference signal Δ fPoint(t), by i1(t)、i2(t)
PGC demodulation is in pll reference signal Δ fPoint(t), then the motion measurement optical output that balanced detector (14) detects after locking phase
Signal is i '1(t)；
The 1 bugle call optical modulator (18) and 2 bugle call optical modulator (19) difference frequencies letter that No. 2 photodetectors (23) are detected after locking phase
Number be i '2(t)；
Step 3: the motion measurement optical output signal that balanced detector after locking phase (14) is detected is i '1(t) and 2 after locking phase
The 1 bugle call optical modulator (18) and 2 bugle call optical modulator (19) difference frequency signals that number photodetector (23) detects are i '2(t)
After external cavity laser (1) exports optical frequency f (t) synchronized sampling, the motion measurement optical path that balanced detector (14) detects is defeated
The 1 bugle call optical modulator (18) and 2 bugle call optical modulator (19) difference frequencies letter that signal and No. 2 photodetectors (23) are detected out
Number be respectively i1(k) and i2(k)；
Step 4: signal i in extraction step onem(k), signal i in step 31(k)、i2(k) the phase changing capacity ΔΦ inm(k)、
ΔΦ1(k)、ΔΦ2(k), by ΔΦ1(k)、ΔΦ2(k) the group delay time difference variation delta τ of corresponding measured target is obtainedm(k), will
Δτm(k) ΔΦ is brought intom(k) the group delay time difference τ that corresponding measured target generates is obtained afterm0, according to Δ τm(k) and τm0Obtain dynamic
The distance R (k) of measured target；
In the step 1 when measured target is dynamic object, detected through frequency sweep interfeerometry ranging optical-circuit balance detector (14)
Output signal im(k) are as follows:
Wherein, AmAmplitude for the signal detected through frequency sweep interfeerometry ranging optical-circuit balance detector (14), τ0For auxiliary interferometer
The delay inequality that 1 arm length difference generates, k is sampled point, τm0Indicate the group delay time difference that corresponding measured target generates；f0Indicate external cavity type
Laser (1) starting output light frequency；Δτm(k) indicate that each sampled point corresponds to the group delay time difference variable quantity of measured target；
Balanced detector (14) detect through motion measurement optical output signal i1(t) are as follows:
The 1 bugle call optical modulator (18) and 2 bugle call optical modulator (19) difference frequency signal i that No. 2 photodetectors (23) are detected2(t)
Are as follows:
i2(t)=A2cos[2π(fAOM1-fAOM2) t]=A2cos[2πΔfAOMt] (3)
Wherein, A1Indicate the motion measurement optical output signal i that balanced detector (14) are detected1(t) amplitude, A2Indicate No. 2
The 1 bugle call optical modulator (18) and 2 bugle call optical modulator (19) difference frequency signal i that photodetector (23) detects2(t) vibration
Width, t are sampled point, fAOM1Indicate the shift frequency amount of 1 bugle call optical modulator (18), fAOM2Indicate the shift frequency of 2 bugle call optical modulators (19)
Amount, Δ fAOMIndicate that 1 bugle call optical modulator (18) and 2 bugle call optical modulator (19) shift frequencies are poor, f '0It indicates single-frequency laser (16)
Output light frequency；τm(t) the group delay time difference that corresponding measured target generates is indicated；Δτm(t) group of corresponding measured target is indicated
Delay inequality variable quantity；
Using No. 2 auxiliary interferometer (26) output signals as pll reference signal Δ f in the step 2Point(t), by i1(t)、i2
(t) PGC demodulation is in pll reference signal Δ fPoint(t), then the motion measurement optical path that balanced detector (14) detects after locking phase
Output signal is i '1(t)；
The 1 bugle call optical modulator (18) and 2 bugle call optical modulator (19) difference frequencies letter that No. 2 photodetectors (23) are detected after locking phase
Number be i '2(t)；
Detailed process are as follows:
No. 2 auxiliary interferometer (26) output signals are as pll reference signal Δ fPoint(t), then have:
Wherein, Δ f (t) is the equal optical frequency intervals of No. 1 auxiliary interferometer (2) output；M is that No. 2 auxiliary interferometers (26) compare No. 1
The frequency dividing multiple of auxiliary interferometer (2), by the frequency shift amount f for changing 2 bugle call optical modulators (19)AOM2, by formula (2), (3)
2 π Δ f of phaseAOMT is locked in pll reference signal Δ fPoint(t), i.e.,
Wherein ΔΦlockFor i ' after locking phase1(t) fixed skew part, the then fortune that balanced detector (14) detects after locking phase
Dynamic optical path output signal are as follows:
The 1 bugle call optical modulator (18) and 2 bugle call optical modulator (19) difference frequencies letter that No. 2 photodetectors (23) are detected after locking phase
Number i '2(t) are as follows:
6. the dynamic frequency scanning interfeerometry ranging method according to claim 5 based on optics frequency dividing locking phase gamma correction, special
Sign is: the motion measurement optical output signal for detecting balanced detector after locking phase (14) in the step 3 is i '1(t)
The 1 bugle call optical modulator (18) and 2 bugle call optical modulator (19) difference frequency signals detected with No. 2 detectors after locking phase is i '2(t)
After external cavity laser (1) exports optical frequency f (t) synchronized sampling, the motion measurement optical path that balanced detector (14) detects is defeated
The 1 bugle call optical modulator (18) and 2 bugle call optical modulator (19) difference frequencies letter that signal and No. 2 photodetectors (23) are detected out
Number be respectively i1(k) and i2(k)；Detailed process are as follows:
I ' in formula (8)1(t) and formula (9) in i '2(t) optical frequency f (t) synchronized sampling is exported through external cavity laser (1)
Afterwards, the motion measurement optical output signal i that balanced detector (14) detects1(k) and No. 2 photodetectors (23) are detected
1 bugle call optical modulator (18) and 2 bugle call optical modulator (19) difference frequency signal i2(k) it is respectively as follows:
7. the dynamic frequency scanning interfeerometry ranging method according to claim 6 based on optics frequency dividing locking phase gamma correction, special
Sign is: signal i in extraction step one in the step 4m(k), signal i in step 31(k)、i2(k) phase changing capacity in
ΔΦm(k)、ΔΦ1(k)、ΔΦ2(k), by ΔΦ1(k)、ΔΦ2(k) the group delay time difference variable quantity of corresponding measured target is obtained
Δτm(k), by Δ τm(k) ΔΦ is brought intom(k) the group delay time difference τ that corresponding measured target generates is obtained afterm0, according to Δ τm(k) and
τm0Obtain the distance R (k) of dynamic measured target；Detailed process are as follows:
Extract formula (1), (10), the phase changing capacity ΔΦ in (11) signalm(k)、ΔΦ1(k)、ΔΦ2(k), it is respectively as follows:
It can be obtained by formula (13), (14) simultaneous:
It is obtained after bringing formula (15) into formula (12):
The then distance of dynamic measured target are as follows:
N in formulaairFor air refraction, c is the light velocity.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08292262A (en) * | 1995-04-24 | 1996-11-05 | Opt:Kk | Electronic distance meter |
| WO2002004925A1 (en) * | 2000-07-05 | 2002-01-17 | The University Of Western Australia | Method and apparatus for determining one or more properties of a sample in optical coherence tomography |
| CN105136021A (en) * | 2015-07-24 | 2015-12-09 | 哈尔滨工业大学 | Laser frequency scanning interferometer dispersion phase compensation method based on focusing definition evaluation function |
| CN106226775A (en) * | 2016-07-15 | 2016-12-14 | 哈尔滨工业大学 | A kind of absolute distance dynamic measurement system based on swept frequency interferometer and measuring method thereof |
| CN107728134A (en) * | 2017-11-02 | 2018-02-23 | 杭州电子科技大学 | The FM-CW laser ranging device of integrated reference path systems stabilisation |
-
2018
- 2018-09-11 CN CN201811057540.8A patent/CN109029246A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08292262A (en) * | 1995-04-24 | 1996-11-05 | Opt:Kk | Electronic distance meter |
| WO2002004925A1 (en) * | 2000-07-05 | 2002-01-17 | The University Of Western Australia | Method and apparatus for determining one or more properties of a sample in optical coherence tomography |
| CN105136021A (en) * | 2015-07-24 | 2015-12-09 | 哈尔滨工业大学 | Laser frequency scanning interferometer dispersion phase compensation method based on focusing definition evaluation function |
| CN106226775A (en) * | 2016-07-15 | 2016-12-14 | 哈尔滨工业大学 | A kind of absolute distance dynamic measurement system based on swept frequency interferometer and measuring method thereof |
| CN107728134A (en) * | 2017-11-02 | 2018-02-23 | 杭州电子科技大学 | The FM-CW laser ranging device of integrated reference path systems stabilisation |
Non-Patent Citations (1)
| Title |
|---|
| 路程: "基于宽带扫描干涉的高精度绝对距离测量方法研究", 《中国博士学位论文全文数据库工程科技II辑》 * |
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