CN111123286A - Self-calibration-based all-fiber Doppler cable length testing method and device - Google Patents
Self-calibration-based all-fiber Doppler cable length testing method and device Download PDFInfo
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
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- G01S17/06—Systems determining position data of a target
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- G—PHYSICS
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- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
- G01S17/02—Systems using the reflection of electromagnetic waves other than radio waves
- G01S17/50—Systems of measurement based on relative movement of target
- G01S17/58—Velocity or trajectory determination systems; Sense-of-movement determination systems
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
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Abstract
The invention relates to a self-calibration-based all-fiber Doppler cable length testing method and device. The measuring method of the invention comprises the steps that two lasers with the same frequency simultaneously irradiate different positions of a cable to generate diffuse reflection, the diffuse reflection is received by two photoelectric detectors with the same type and number, then, the two signals are subjected to pre-processing and then transmitted to a signal processing module; the signal processing module performs sampling integral processing and fast Fourier transform to extract Doppler frequency, and optimizes the frequency spectrums of the two Doppler frequencies by adopting frequency spectrum refinement and frequency spectrum correction to obtain two speed values; comparing the two values, judging whether the two values are within an error range, and if not, performing frequency stabilization on the laser 1 so as to optimize a light source; and finally, obtaining a group of data values through multiple measurements, taking the optimal speed solution, and integrating the optimal speed solution to obtain the length of the tested cable. The method solves the problem of low precision of the traditional method for measuring the length of the cable, and improves the stability and precision of the system.
Description
Technical Field
The invention relates to the technical field of laser Doppler velocity measurement, in particular to a self-calibration-based all-fiber Doppler cable length testing method and device.
Background
The laser Doppler velocity measurement technology has the advantages of high measurement precision, capability of measuring the velocity of a plurality of objects in real time on line, very wide velocity measurement range, very clear spatial resolution, strong external interference resistance, difficult influence of various severe environments and the like. Therefore, the laser Doppler velocity measurement technology can be applied to many fields, such as aerospace industry, hydromechanics, medicine, military industry, civil use and the like. The laser Doppler velocity measurement technology is carried out according to Doppler effect and photoelectric heterodyne detection, and the principle is that a laser emits a beam of laser, the laser irradiates an object to be measured through a light path, at the moment, diffuse reflection is generated, light reflected by the object can be received and transmitted to a photoelectric detector through optical elements such as a focusing lens or a collimator, then an optical signal is converted into an electric signal by the photoelectric detector, the electric signal is transmitted to a signal processing module to carry out Doppler frequency extraction, and finally the velocity value of the object to be measured is obtained.
In the laser doppler velocity measurement technology, how to process the measured doppler signals is the final key technology of the system, which is very important, and the quality of the doppler signal processing directly affects whether the accuracy of the measured velocity value is high enough. This is because the doppler velocity measurement signal mainly originates from the scattered light of the particles, and the intensity of the scattered light is relatively weak, so that the processing of the signal becomes particularly difficult in this respect; in practice, a large amount of noise signals and other interference signals, such as ambient light current noise, light source intensity noise, dark current noise, signal current noise, and phase noise caused by thermal noise and multi-particle superposition, are also doped in the measured doppler velocity measurement signal, which results in that in actual measurement, the signal-to-noise ratio of the doppler velocity measurement signal is relatively low, and the low signal-to-noise ratio has a great influence on subsequent signal processing and precision value, so that it is an important part to improve the signal-to-noise ratio in signal processing, and the laser doppler velocity measurement signal is also affected by signal drop, spectrum broadening, and the like. In order to accurately extract useful speed information under the conditions of low signal-to-noise ratio and weak signals and meet the requirements of high measurement precision, wide measurement range and high response speed, the method provides more strict technical requirements for post-processing of laser Doppler velocity measurement signals. The method is not optimized for the stability of laser frequency and the adaptability of the whole system device, so that the judgment of a measured value and an error range is influenced due to the unstable laser frequency or external interference, and integration and packaging are difficult to realize. Currently, as the application of the laser doppler velocity measurement technology is more and more widespread, the processing level requirement for the doppler velocity measurement signal is higher and higher. For example, the advent of instantaneous sampling techniques, the popularity of fast fourier transforms, and the application of short-time fourier transforms. Due to the emergence of the new signal processing technologies, the processing of the speed measurement signal is improved in the aspects of measurement precision and response speed. Currently, the commonly used doppler velocity measurement signal processing methods can be classified into the following five categories according to their working principles: spectrum analysis, filter bank, frequency tracking, counting, and fast fourier transform.
According to investigation, the application of the cable in daily life is very wide, the production of the cable is an important process, at present, cable production enterprises with large and small sizes in China have about ten thousand families, but because the laser Doppler velocity measurement technology is not mature in China, most of the cable production enterprises still use the traditional cable measurement mode, and in the traditional cable measurement, because the cable materials are different, the friction coefficients are different, the slipping phenomenon which cannot be avoided when the pulley rotates is caused, so that a great error is brought to the cable measurement precision, the cost and the profit of the enterprises are influenced, and the requirement on the cable measurement precision is difficult to achieve. Compared with the traditional cable measuring method, the method has the advantages that the frequency stabilization processing automatic calibration technology is adopted, the stability of the speed measuring system is improved, the measuring precision is obviously enhanced, and the optical devices are connected by the full optical fibers, so that the adaptability and the anti-interference capability are better.
Disclosure of Invention
The invention provides a self-calibration-based all-fiber Doppler cable length testing method and a self-calibration-based all-fiber Doppler cable length testing device, and aims to solve the problems that when the length of a cable is measured by using a traditional method, the transmission pulley slipping phenomenon occurs and the measurement accuracy of the length of the cable is low due to different surface friction coefficients caused by different cable materials.
In order to achieve the purpose, the invention adopts the following technical scheme:
a self-calibration-based all-fiber Doppler cable length testing method is characterized by comprising the following steps:
(1) two lasers with the same frequency are simultaneously irradiated on different positions of a cable to generate diffuse reflection which is received by two photoelectric detectors with the same type and number, and then the two converted electric signals are subjected to pre-processing;
(2) then transmitting the signals to a signal processing module, firstly carrying out sampling integral processing, then carrying out fast Fourier transform to extract Doppler frequency, and optimizing the frequency spectrums of the two Doppler frequencies by adopting frequency spectrum refinement and frequency spectrum correction to finally obtain two speed values;
(3) and recording and comparing the two numerical values, judging whether the speed value is within an error range, if not, performing frequency stabilization treatment on the laser 1(1) so as to optimize the light source, finally performing multiple measurements to obtain a group of data values, taking an optimal speed solution, and integrating the optimal speed solution to obtain the length of the measured cable.
Specifically, the step (1) is as follows: according to the Doppler effect, a light source emits a beam of light which is irradiated on an object to be measured and scattered on the surface of the object to be measured, the frequency of the light received by the object to be measured and the frequency of the light emitted by the light source are different, so that a frequency difference is generated between the light received by the object to be measured and the light emitted by the light source, the frequency is received and converted by a photoelectric detector, and an output signal carries information of the movement speed of the object.
Specifically, the step (2) is as follows: the method comprises the steps of converting optical signals and electric signals of a photoelectric detector, amplifying and filtering the converted electric signals, sampling and integrating the transmitted signals to obtain an average value, then carrying out fast Fourier transform to extract Doppler frequency, further carrying out frequency spectrum refinement because frequency points after fast Fourier transform operation are discrete points, regarding the frequency points as continuous, further correcting to obtain a better frequency spectrum, and improving the accuracy of a speed value.
Specifically, the step (3) is as follows: when the measured speed value is not ideal, the laser 1(1) is returned again to perform stable laser frequency regulation, the frequency discriminator sends out a corresponding frequency discrimination signal (7-1-3) after the input signal (7-1-2) passes through the frequency discriminator (7-1), the frequency discriminator transmits the signal to the controller (7-4), and the controller (7-4) performs frequency regulation on the laser 1(1) according to the transmitted frequency discrimination signal (7-1-3), so that the output frequency is more stable, and the accuracy of speed solution is improved through self-calibration for a plurality of times.
In order to achieve the above object, the present invention further provides an all-fiber doppler cable length testing device based on self-calibration, comprising: the device comprises a laser 1(1), a laser 2(2), a photoelectric detector 1(3), a photoelectric detector 2(4), a pre-processing module (5), a signal processing module (6), a frequency stabilization processing module (7) and a tested cable (8), wherein the laser 1(1), the laser 2(2), the photoelectric detector 1(3), the photoelectric detector 2(4) and the frequency stabilization processing module (7) are all connected by optical fibers.
Specifically, the laser 1(1), the laser 2(2) are semiconductor lasers, and are used for emitting laser to irradiate the cable (8) to be tested.
Specifically, the photodetectors 1(3) and 2(4) are used for receiving reflected light generated by the laser beam irradiating on the cable, then converting the optical signal into an electrical signal, and transmitting the electrical signal to the preprocessing module (5) for amplifying and filtering the received electrical signal.
Specifically, the signal processing module (6) performs sampling integration noise reduction on the processed electric signal, extracts Doppler frequency through fast Fourier transform, and performs spectrum refinement and correction.
Specifically, after the frequency stabilization processing module (7) performs frequency stabilization processing on the laser 1(2), the measurement work is continued, and the frequency stabilization processing module is compared with the measurement value of the laser 2(2), and finally, an optimal speed value is obtained, so that the automatic calibration function is achieved.
Compared with the prior art, the invention has the beneficial effects that: in the scheme, because the frequency stabilization processing automatic calibration technology is adopted, the stability of the speed measuring device is improved, the measuring precision is obviously enhanced, and the flexibility is more free; all optical devices are connected by optical fibers, so that the optical path is more stable, the transmission effect is better, the adaptability and the anti-interference capability are stronger, and an ideal accurate result for measuring the length of the cable is achieved.
Drawings
FIG. 1 is a flow chart of a cable length testing method according to an embodiment of the present invention;
FIG. 2 is a flow chart of signal processing according to an embodiment of the present invention;
FIG. 3 is a flowchart illustrating a spectrum refinement method according to an embodiment of the present invention;
fig. 4 is a structural diagram of a frequency stabilization processing module according to an embodiment of the present invention.
Detailed Description
The invention will be further illustrated by the following examples in conjunction with the drawings in which:
the utility model provides a based on self calibration all-fiber Doppler cable length testing arrangement which characterized in that: the device comprises a laser 1(1), a laser 2(2), a photoelectric detector 1(3), a photoelectric detector 2(4), a pre-processing module (5), a signal processing module (6), a frequency stabilization processing module (7) and a tested cable (8), wherein the laser 1(1), the laser 2(2), the photoelectric detector 1(3), the photoelectric detector 2(4) and the frequency stabilization processing module (7) are all connected by optical fibers.
The laser 1(1) and the laser 2(2) are semiconductor lasers and are used for emitting laser to irradiate the cable (8) to be tested.
The photoelectric detectors 1 and 2 and 4 are used for receiving reflected light generated by the laser beam irradiating on the cable, then converting the optical signal into an electrical signal, and transmitting the electrical signal to the preprocessing module (5) for amplifying and filtering the received electrical signal.
And the signal processing module (6) is used for sampling, integrating and denoising the processed electric signals, extracting Doppler frequency through fast Fourier transform, and refining and correcting frequency spectrum.
The frequency stabilization processing module (7) performs frequency stabilization processing on the laser 1(2), continues to perform measurement work, compares the frequency stabilization processing with the measurement value of the laser 2(2), and finally obtains an optimal speed value to play a role in automatic calibration.
As shown in fig. 1, the working steps are as follows:
(1) two lasers with the same frequency are simultaneously irradiated on different positions of a cable to generate diffuse reflection which is received by two photoelectric detectors with the same type and number, and then the two converted electric signals are subjected to pre-processing;
(2) then transmitting the signals to a signal processing module, firstly carrying out sampling integral processing, then carrying out fast Fourier transform to extract Doppler frequency, and optimizing the frequency spectrums of the two Doppler frequencies by adopting frequency spectrum refinement and frequency spectrum correction to finally obtain two speed values;
(3) and recording and comparing the two numerical values, judging whether the speed value is within an error range, if not, performing frequency stabilization treatment on the laser 1(1) so as to optimize the light source, finally performing multiple measurements to obtain a group of data values, taking an optimal speed solution, and integrating the optimal speed solution to obtain the length of the measured cable.
As shown in fig. 2, the working steps are as follows:
the noise reduction is carried out through sampling integration (6-1), because the noise interference on each signal is not much the same, the noise interference does not contain a periodic rule, therefore, the first step of the time adopts a sampling integration technology, the working principle is that in the period of each signal, the same part of signals can be selected, integration processing is carried out firstly, and an average value is obtained, and under the general condition, the noise doped in the signals can be removed well as long as the sampling integration times are sufficient. And then, extracting Doppler frequency through fast Fourier transform (FFT-1) (6-2), then, thinning the spectrum of the extracted Doppler signal (6-3), and further performing spectrum ratio correction (6-4) after the spectrum is thinned (6-3).
Although it is easier to process signals in the time domain, it has a serious drawback that the reliability is greatly reduced when the signal-to-noise ratio is low. Therefore, currently, the laser doppler velocimetry signal processing is generally performed in the frequency domain, i.e. the doppler signal obtained by detection is converted into its own spectrogram, then fast fourier transform (FFT-1) (6-2) is performed, and the maximum value of its frequency spectrum is obtained, and finally the doppler frequency shift frequency is obtained by resolving the maximum value of the frequency spectrum. FFT-1(6-2) mainly divides the N-point Discrete Fourier Transform (DFT) into several smaller DFTs, which both increases its speed and significantly reduces its computation compared to the original overall DFT, and the computation results between the two are the same. For example, an N-point data sequence may be decomposed into two N/2 point sequences by a base-2 time domain decimation method, so that the calculation speed is reduced by half, and in the same way, the two N/2 point sequences may be decomposed into four N/4 point sequences, and the four N/4 point sequences may be subjected to separate DFT, so that the calculation speed may be further increased. This decomposition process may be continued until a 2-point DFT is broken.
If the length of the signal data is L, the DFT expression of N points is:
wherein N is the DFT conversion point number and satisfies N is more than or equal to L,
the expression of the inverse discrete fourier transform of N points is:
as can be seen from the above expression, the finite sequence x (k) is x (N) the N-point spectrum distribution function obtained by DFT, and when N is different, the calculation results obtained by DFT are also different. And the value of N is not too small, because when N is too small, the obtained frequency distribution function can not show the frequency characteristic of the original function. The frequency resolution is actually the interval between two adjacent spectral lines in the spectrogram, and in practical application, the frequency characteristic of the original waveform must be reflected, so that the distance 2 pi/N between two adjacent spectral lines should satisfy the following formula:
from the above formula, it can be seen that: to make x (N) perform the corresponding operation on each value of the N-point dftx (k), N is required to be performed in each step2The sub-product is summed with N (N-1) times. Due to N2Proportional to the number of multiplication and the number of operation, so that when the value of N rises, the calculation amount of DFT is N2This greatly increases the amount of DFT computation.
Therefore, the FFT-1(6-2) and the DFT are the same in the aspect of operation results, the working principle of the FFT-1(6-2) is similar to that of the DFT, and the difference is that the FFT-1(6-2) optimizes the DFT, so that the operation speed is improved, and the calculation amount in the operation process is reduced. And FFT-1(6-2) can efficiently extract useful doppler signals from low signal-to-noise, so the technique of FFT-1(6-2) is cited.
The spectral ratio correction (6-4) is mainly performed by using two spectral lines in the spectral main lobe, and assuming that the two spectral lines have sequences x and x +1, respectively, and their corresponding amplitudes are ykAnd yk+1Is provided with
The spectral modification value expression is:
Δk＝-g(r)
then ak is the spectral correction value and g (r) is a function related to the window function, so the above equation continues to be:
therefore, by using the formula, the corrected value of the frequency spectrum can be obtained, and more accurate Doppler frequency can be obtained.
As shown in fig. 3, the working steps are as follows:
FFT-2(6-3-2) is carried out on the sampling frequency processed by the sampling integration (6-1) to obtain the center frequency (6-3-3) of the refined frequency band, the other end of the sampling frequency is operated in a complex multiplier (6-3-6) through a random access memory (6-3-5) and the center frequency (6-3-3) processed by a digital oscilloscope (6-3-4), and the digital oscilloscope (6-3-4) has the function that when the analog signal passes through the digital oscilloscope (6-3-4), the digital oscilloscope (6-3-4) can automatically complete A/D conversion according to the set sampling frequency, convert the analog signal into the digital signal and directly display the waveform of the digital signal through a screen. Finally, the frequency spectrum after operation is subjected to frequency spectrum analysis (6-3-7), the divided frequency spectrum is subjected to frequency spectrum refinement (6-3-8), as FFT-2(6-3-2) is a frequency spectrum value expressed as each discrete frequency, and the purpose of refinement is to convert the conversion into a continuous frequency spectrum value, a refinement evaluation expression is as follows:
by the expression, the resolution ratio of the frequency can be solved, and the optimal thinning multiple is determined by the value of the resolution ratio, so that the thinned frequency spectrum is clearer, and the measuring effect is better.
As shown in fig. 4, the working steps are as follows:
if the measured speed value is not ideal, the laser 1(1) is returned again to perform stable laser frequency regulation, a frequency stabilizing processing module is needed in the period, the laser is influenced by external environment interference and the like, so that the output frequency of the laser deviates from the reference frequency when the length of the cable is measured, therefore, after the input signal (7-1-2) passes through the frequency discriminator (7-1), the frequency discriminator can send a corresponding frequency discrimination signal (7-1-3) to be transmitted to the controller (7-4), and the controller (7-4) can perform frequency regulation on the laser 1(1) according to the transmitted frequency discrimination signal (7-1-3), so that the output frequency of the laser is more stable, and the accuracy of speed regulation is greatly improved after a plurality of times of self-calibration.
Claims (9)
1. A self-calibration-based all-fiber Doppler cable length testing method is characterized by comprising the following steps:
(1) two lasers with the same frequency are simultaneously irradiated on different positions of a cable to generate diffuse reflection which is received by two photoelectric detectors with the same type and number, and then the two converted electric signals are subjected to pre-processing;
(2) then transmitting the signals to a signal processing module, firstly carrying out sampling integral processing, then carrying out fast Fourier transform to extract Doppler frequency, and optimizing the frequency spectrums of the two Doppler frequencies by adopting frequency spectrum refinement and frequency spectrum correction to finally obtain two speed values;
(3) and recording and comparing the two numerical values, judging whether the speed value is within an error range, if not, performing frequency stabilization treatment on the laser 1(1) so as to optimize the light source, finally performing multiple measurements to obtain a group of data values, taking an optimal speed solution, and integrating the optimal speed solution to obtain the length of the measured cable.
2. The self-calibration-based all-fiber Doppler cable length testing method as claimed in claim 1, wherein: the step (1) is as follows: according to the Doppler effect, a light source emits a beam of light which is irradiated on an object to be measured and scattered on the surface of the object to be measured, the frequency of the light received by the object to be measured and the frequency of the light emitted by the light source are different, so that a frequency difference is generated between the light received by the object to be measured and the light emitted by the light source, the frequency is received and converted by a photoelectric detector, and an output signal carries information of the movement speed of the object.
3. The self-calibration-based all-fiber Doppler cable length testing method as claimed in claim 1, wherein: the step (2) is as follows: the method comprises the steps of converting optical signals and electric signals of a photoelectric detector, amplifying and filtering the converted electric signals, sampling and integrating the transmitted signals to obtain an average value, then carrying out fast Fourier transform to extract Doppler frequency, further carrying out frequency spectrum refinement because frequency points after fast Fourier transform operation are discrete points, regarding the frequency points as continuous, further correcting to obtain a better frequency spectrum, and improving the accuracy of a speed value.
4. The self-calibration-based all-fiber Doppler cable length testing method as claimed in claim 1, wherein: the step (3) is as follows: when the measured speed value is not ideal, the laser 1(1) is returned again to perform stable laser frequency regulation, the frequency discriminator sends out a corresponding frequency discrimination signal (7-1-3) after the input signal (7-1-2) passes through the frequency discriminator (7-1), the frequency discriminator transmits the signal to the controller (7-4), and the controller (7-4) performs frequency regulation on the laser 1(1) according to the transmitted frequency discrimination signal (7-1-3), so that the output frequency is more stable, and the accuracy of speed solution is improved through self-calibration for a plurality of times.
5. The utility model provides a based on self calibration all-fiber Doppler cable length testing arrangement which characterized in that: the device comprises a laser 1(1), a laser 2(2), a photoelectric detector 1(3), a photoelectric detector 2(4), a pre-processing module (5), a signal processing module (6), a frequency stabilization processing module (7) and a tested cable (8), wherein the laser 1(1), the laser 2(2), the photoelectric detector 1(3), the photoelectric detector 2(4) and the frequency stabilization processing module (7) are all connected by optical fibers.
6. The self-calibration-based all-fiber Doppler cable length testing device according to claim 5, wherein: the laser 1(1) and the laser 2(2) are semiconductor lasers and are used for emitting laser to irradiate the cable (8) to be tested.
7. The self-calibration-based all-fiber Doppler cable length testing device according to claim 5, wherein: the photoelectric detectors 1 and 2 and 4 are used for receiving reflected light generated by the laser beam irradiating on the cable, then converting the optical signal into an electrical signal, and transmitting the electrical signal to the preprocessing module (5) for amplifying and filtering the received electrical signal.
8. The self-calibration-based all-fiber Doppler cable length testing device according to claim 5, wherein: and the signal processing module (6) is used for sampling, integrating and denoising the processed electric signals, extracting Doppler frequency through fast Fourier transform, and refining and correcting frequency spectrum.
9. The self-calibration-based all-fiber Doppler cable length testing device according to claim 5, wherein: the frequency stabilization processing module (7) performs frequency stabilization processing on the laser 1(2), continues to perform measurement work, compares the frequency stabilization processing with the measurement value of the laser 2(2), and finally obtains an optimal speed value to play a role in automatic calibration.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111766597A (en) * | 2020-07-08 | 2020-10-13 | 哈尔滨理工大学 | Frequency measurement method and device for frequency modulation continuous wave laser ranging beat signal |
| CN115015942A (en) * | 2022-08-09 | 2022-09-06 | 中国人民解放军军事科学院国防科技创新研究院 | Self-adaptive underwater target acoustic speed measurement device and method |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104198057A (en) * | 2014-09-23 | 2014-12-10 | 南京中科神光科技有限公司 | Method and device for measuring frequency stability of single-frequency pulse laser |
| CN106707292A (en) * | 2017-01-03 | 2017-05-24 | 濮阳光电产业技术研究院 | Doppler velocity measurement system based on optoelectronic oscillation |
| CN107437722A (en) * | 2016-10-25 | 2017-12-05 | 中国科学院福建物质结构研究所 | A kind of modulation free frequency stabilization method and apparatus of semiconductor laser |
| CN108549086A (en) * | 2018-03-20 | 2018-09-18 | 天津大学 | Laser Doppler signal cake resistancet is adaptively selected and test method |
| CN109374914A (en) * | 2018-09-18 | 2019-02-22 | 西安工业大学 | Larger Dynamic measurement range all -fiber Doppler speed measuring device |
| CN110411552A (en) * | 2019-07-22 | 2019-11-05 | 中国科学院电子学研究所 | Photo-acoustic sound working sensor point deviates judgment method and its device |
-
2020
- 2020-01-12 CN CN202010030059.0A patent/CN111123286A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104198057A (en) * | 2014-09-23 | 2014-12-10 | 南京中科神光科技有限公司 | Method and device for measuring frequency stability of single-frequency pulse laser |
| CN107437722A (en) * | 2016-10-25 | 2017-12-05 | 中国科学院福建物质结构研究所 | A kind of modulation free frequency stabilization method and apparatus of semiconductor laser |
| CN106707292A (en) * | 2017-01-03 | 2017-05-24 | 濮阳光电产业技术研究院 | Doppler velocity measurement system based on optoelectronic oscillation |
| CN108549086A (en) * | 2018-03-20 | 2018-09-18 | 天津大学 | Laser Doppler signal cake resistancet is adaptively selected and test method |
| CN109374914A (en) * | 2018-09-18 | 2019-02-22 | 西安工业大学 | Larger Dynamic measurement range all -fiber Doppler speed measuring device |
| CN110411552A (en) * | 2019-07-22 | 2019-11-05 | 中国科学院电子学研究所 | Photo-acoustic sound working sensor point deviates judgment method and its device |
Non-Patent Citations (4)
| Title |
|---|
| 刘亚俊: "线缆计米器非接触式在线校准", 《上海计量测试》 * |
| 安居 等: "利用激光多普勒效应进行电缆动态定长的研究", 《计量测试与检定》 * |
| 白金成: "电缆激光多普勒在线计米***", 《中国优秀博硕士学位论文全文数据库（硕士） 工程科技II辑》 * |
| 韩顺利 等: "半导体激光器稳频技术", 《红外与激光工程》 * |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN111766597A (en) * | 2020-07-08 | 2020-10-13 | 哈尔滨理工大学 | Frequency measurement method and device for frequency modulation continuous wave laser ranging beat signal |
| CN111766597B (en) * | 2020-07-08 | 2022-05-13 | 哈尔滨理工大学 | Frequency measuring method and device for frequency-modulated continuous wave laser ranging beat signal |
| CN115015942A (en) * | 2022-08-09 | 2022-09-06 | 中国人民解放军军事科学院国防科技创新研究院 | Self-adaptive underwater target acoustic speed measurement device and method |
| CN115015942B (en) * | 2022-08-09 | 2022-11-01 | 中国人民解放军军事科学院国防科技创新研究院 | Self-adaptive underwater target acoustic speed measurement device and method |
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