CN1844951A - Apparatus and method for distance measurement using chaos laser of optical fiber laser device - Google Patents
Apparatus and method for distance measurement using chaos laser of optical fiber laser device Download PDFInfo
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- CN1844951A CN1844951A CN 200610012676 CN200610012676A CN1844951A CN 1844951 A CN1844951 A CN 1844951A CN 200610012676 CN200610012676 CN 200610012676 CN 200610012676 A CN200610012676 A CN 200610012676A CN 1844951 A CN1844951 A CN 1844951A
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Abstract
The invention relates to an optical fiber laser chaos laser ranging device and relative method. It is characterized in that: the chaos optical fiber laser uses the optical fiber laser to generate chaos laser signal, and via the optical fiber coupler II to divide the chaos laser signal into the detecting light I and the reference light II; the detecting light I via the optical fiber amplified is amplified to irradiate the object via the laser collimate system; the reflective wave signal of object is collected by the telescope and transformed into electric signal via the optical electric detector I; then via A/D converter, the analogue signal is transformed into digital signal to be input into computer; the reference light II directly irradiates the optical electric detector II whose properties are same to the optical fiber amplifier, to transform the optical signal into electric signal, then via the A/D converter, to be transmitted to the adjustable electric delay wire to be input into the computer; then attaining the detected distance. The invention uses the chaos laser signal generated by the optical fiber laser to range, uses the cross-correlation character of chaos laser to extract the laser fly time, with high anti-disturb ability, high noise tolerance, high accuracy and wider detecting range.
Description
Technical field
The invention belongs to laser distance measurement method and device field.Particularly utilize fiber laser to produce method and device thereof that the chaotic laser light signal is realized precision ranging, can be applicable to fields such as industrial and agricultural production, military affairs, communication, remote sensing.
Background technology
Laser ranging is one of preferred option of measuring distance, and it is a kind of method that the characteristics such as monochromaticity, coherence and high directivity of utilizing laser realize the high precision range observation.That laser ranging is at present extensively adopted is time-of-flight method (The Flight-time Measurement Methods).Its principle be by the measuring light signal on the survey line from the stadimeter to the object between the required time Δ t of shuttle flight, calculate testing distance D according to D=c Δ t/2 then, wherein c is the light velocity.From technological approaches, mainly can be divided into pulse type laser range finding and the laser ranging of continuous wave phase type.
The pulse type laser range finding is to utilize stadimeter to send a laser pulse to target, reflected back on the optical sensor components of stadimeter by object again, and by Δ t two-way time of pulsed light under the timer record, thus a kind of method of acquisition testing distance.Its major defect is that distance accuracy is relatively poor, and representative value is several meters, exists simultaneously and measures the blind area, and promptly minimum measuring distance is generally tens meters, and for improving the timekeeping system that precision needs high performance laser instrument emission ultrashort pulse and can respond fast.
The laser ranging of continuous wave phase type is to come the indirect determination distance-finding method of two-way time by measuring the phase change that produces after modulated laser comes and goes.Light source in the stadimeter sends continuous light, by becoming light modulated directive target after the modulators modulate, the light intensity of the light modulated cycle of intercropping at any time changes, by measuring modulation signal complete cycle issue n and the not enough one-period phase value ' in the light wave two-way process, calculate Δ t two-way time by Δ t=(2n π+ ')/(2 π f).Thereby obtain testing distance D.Though use this method can obtain to be generally several millimeters than high measurement accuracy, its measuring distance is shorter, be generally tens meters, and when this method range finding of utilization,, require the period T of modulation signal as far as possible little, but the reduction in modulation signal cycle has reduced its measuring distance again for improving measuring accuracy.In addition, use this method to need accurate Sine Modulated circuit.
Summary of the invention
The object of the present invention is to provide a kind of Apparatus and method for distance measurement using chaos laser of optical fiber laser device, when solving in the prior art directly pulsed laser ranging precision lower, have the range observation blind area, measuring distance is less and need the problem of accurate Sine Modulated circuit during the laser ranging of continuous wave phase type.
Distance measurement using chaos laser of optical fiber laser device device of the present invention comprises chaos fiber laser, fiber coupler, fiber amplifier, laser collimation system, target to be measured, telescope, photodetector, A/D converter, adjustable electric lag line and computing machine, it is characterized in that the chaos fiber laser is to add modulation or utilize two monocycle fiber lasers to form the dicyclo fiber laser by the monocycle fiber laser to produce the chaotic laser light signal, is divided into the chaotic laser light signal by fiber coupler II and surveys light I and reference light II; Surveying light I is shone on the target to be measured through the fiber amplifier amplification again by laser collimation system, the reflection echo signal of target to be measured is collected by telescope and is converted into electric signal by photodetector I, through A/D converter I analog signal conversion is become digital signal input computing machine; Reference light II shines directly on the performance parameter photodetector II identical with fiber amplifier, and light signal is converted into electric signal, is transferred to through A/D converter II to be input to Computer Processing on the adjustable electric lag line and promptly to get testing distance again.
The method that is used for the distance measurement using chaos laser of optical fiber laser device device of the present invention is to utilize the chaos fiber laser to produce the higher-dimension chaotic signal, by fiber coupler I the chaotic laser light signal is divided into detection light I and reference light II, survey light I as distance measuring signal, transmitting mirror by laser collimation system after the process fiber amplifier amplifies is transmitted into target to be measured, utilize telescope to collect target reflection echo chaotic signal to be measured, I converts electric signal to photodetector, converts digital signal input computing machine to by A/D converter I again; Reference light II shines directly into photodetector II, is converted to digital signal input computing machine by A/D converter II again through an adjustable electric lag line; Computing machine carries out simple crosscorrelation relatively to this two paths of signals, calculates Δ t two-way time that surveys light target reflection to be measured, promptly gets testing distance.
The present invention proposes utilize the fiber laser chaotic laser light realize distance measuring equipment and method and formerly technology relatively have following advantage and good effect:
(1) the present invention utilizes chaotic laser light signal that fiber laser produces as distance measuring signal, utilizes the their cross correlation of chaotic laser light to extract the laser flying time, and antijamming capability is strong, and the noise tolerance is big.
(2) compare with technology formerly, the present invention has saved high performance pulsed laser and high-precision Sine Modulated Circuits System, has simplified device, has saved cost.
(3) measuring accuracy height.Adopt the monocycle fiber laser to add modulation or utilize two monocycle fiber lasers to form the dicyclo fiber laser and can produce chaotic signal, this chaotic laser light signal has smooth continuous frequency spectrum, its bandwidth can reach tens GHz, thereby have farsighted distance and a speed resolution characteristic, be applied to range finding, only adopt measurement mechanism simple in structure just can reach cm-level accuracy.
(4) the measuring distance scope is wide.This method does not exist short distance to measure blind spot in theory, and I measures the distance less than 10cm, utilizes the fiber amplifier of higher gain and is adding on the target to be measured under the mated condition of reverberator, and maximum measuring distance can reach thousands of rice.
(5) be beneficial to integrated and systematization.Owing to the flexibility of fiber laser operation material, can make the stadimeter of compact conformation easily; Owing to adopt computing machine to carry out data processing, a plurality of instruments can be formed the range finding network, utilize a computing machine can carry out multimetering.
Description of drawings
Fig. 1 is a monocycle distance measurement using chaos laser of optical fiber laser device apparatus structure synoptic diagram of the present invention
Among the figure: 1: laser pulse driving power 2: semiconductor laser 3: wavelength division multiplexer 4: optoisolator 5: doped fiber 6: fiber coupler I 7: fiber coupler II 8: fiber amplifier 9: laser collimation system 10: target 11 to be measured: telescope 12: photodetector I 13:A/D converter I 14: photodetector II 15:A/D converter II16: adjustable electric lag line 17: computing machine
Embodiment
In fiber laser, produce the chaotic laser light signal that is used to find range, can add modulation or utilize two monocycle fiber lasers to form the generation of dicyclo fiber laser by the monocycle fiber laser.Adding modulation below in conjunction with accompanying drawing with the monocycle fiber laser, to produce that chaotic laser light finds range be that example is described further:
The chaotic laser light signal generation device comprises laser pulse driving power 1, semiconductor laser 2 and the fiber optic loop of being made up of wavelength division multiplexer 3, optoisolator 4, doped fiber 5, fiber coupler I6.Laser pulse driving power 1 provides direct current biasing and modulating current pulse for laser instrument; Semiconductor laser 2 is used for pumping doped fiber 5, and different doped fibers can be selected the semiconductor laser of different wave length for use, as can select the quantum-well laser of 980nm for use for Er-doped fiber; Wavelength division multiplexer 3 is with pumping light coupled into optical fibres ring; The effect of optoisolator 4 is to make laser signal unidirectional operation in ring; Fiber coupler I6 is as output coupler.When regulating laser pulse driving power 1, when making the modulation pumping light of semiconductor laser 2 suitable power of output and repetition frequency, fiber laser can outgoing higher-dimension chaotic laser light signal.Utilize fiber coupler II7 that the chaotic laser light signal is divided into I light and II light.I light is mapped on the target 10 to be measured as surveying illumination after fiber amplifier 8 amplifies again by laser collimation system 9, echoed signal through target 10 reflections to be measured is collected by telescope 11, be converted into electric signal by high sensitivity low noise photodetector I12 again, after A/D converter I13 becomes digital signal with analog signal conversion, be input to computing machine 17; II light shines directly on the identical photodetector II14 of performance parameter and fiber amplifier 8 as reference light, and light signal is converted into electric signal, be transferred to adjustable electric lag line 16 through A/D converter II15 again after, be input to computing machine 17.If the detection light of photodetector I is τ through target reflection to be measured two-way time
0, the functional relation that reference light II satisfies is f (t), then surveying the satisfied functional relation of light I is f (t-τ
0), its cross correlation function then
Have only as τ=τ
0The time, there is unique peak value in cross correlation function.Based on this principle, handle τ two-way time that just can obtain to survey light process target reflection to be measured by computer software
0Thereby, obtain testing distance.The effect of adjustable electric lag line mainly is to be used for demarcating and calibration instrument, with the error that the circuit difference is brought between photodetector I12 and photodetector II14 parameter difference and detection light and the reference light in the elimination practical application.To shine a known gauged distance be on the object of L by surveying light I, and conversion enters computing machine and carries out cross correlation process through A/D respectively with returning the detection light I that comes and reference light II signal.Make the peak value of simple crosscorrelation curve appear at t the time delay of regulating variable delay line 16
0(generally get t
0=0) constantly, keep lag line constant time delay, in the time of will surveying illumination again and be mapped on the target 10 to be measured, the peak value of the autocorrelator trace of acquisition appears at t
1The place then surveys the two-way time τ of light through target 10 reflections to be measured
0=t
1-t
0+ 2L/c.Again according to D=c τ
0/ 2, obtain testing distance.
When measuring the short distance target, can in reference light II, add optical delay line, reference light II directly is coupled into a light simple crosscorrelation instrument with the detection light I that returns carries out simple crosscorrelation, obtain surveying the two-way time τ of light through target reflection to be measured according to cross-correlogram
0Thereby, obtain testing distance.So just save circuit arrangement, realized full photo measure, measuring accuracy can have been brought up to a millimeter magnitude simultaneously, accelerated measuring speed.
Claims (2)
1. distance measurement using chaos laser of optical fiber laser device device, it includes chaos fiber laser, fiber coupler, fiber amplifier, laser collimation system, target to be measured, telescope, photodetector, A/D converter, adjustable electric lag line and computing machine, it is characterized in that the chaos fiber laser is to add modulation or utilize two monocycle fiber lasers to form the dicyclo fiber laser by the monocycle fiber laser to produce the chaotic laser light signal, is divided into the chaotic laser light signal by fiber coupler II (7) and surveys light I and reference light II; Surveying light I is shone on the target to be measured (10) by laser collimation system (9) through fiber amplifier (8) amplification again, the reflection echo signal of target to be measured (10) is collected by telescope (11) and is converted into electric signal by photodetector I (12), through A/D converter I (13) analog signal conversion is become digital signal input computing machine (17); Reference light II shines directly on the performance parameter photodetector II (14) identical with fiber amplifier (8), light signal is converted into electric signal, passes through A/D converter II (15) again and be transferred to and be input to computing machine (17) on the adjustable electric lag line (16) and handle and promptly to get testing distance.
2. the method that is used for the distance measurement using chaos laser of optical fiber laser device device, be characterised in that and utilize the chaos fiber laser to produce the higher-dimension chaotic signal, by fiber coupler I (6) the chaotic laser light signal is divided into detection light I and reference light II, survey light I as distance measuring signal, transmitting mirror by laser collimation system (9) after process fiber amplifier (8) amplifies is transmitted into target to be measured (10), utilize telescope (11) to collect the echo chaotic signal of target to be measured (10) reflection, convert electric signal to photodetector I (12), convert digital signal input computing machine (17) to by A/D converter I (13) again; Reference light II shines directly into photodetector II (14), is converted to digital signal input computing machine (17) by A/D converter II (15) again through an adjustable electric lag line (16); Computing machine (17) carries out simple crosscorrelation relatively to this two paths of signals, calculates Δ t two-way time that surveys light target to be measured (10) reflection, promptly gets testing distance.
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| WO2009097736A1 (en) * | 2008-01-31 | 2009-08-13 | Taiyuan University Of Technology | Chaotic optical time domain reflectometer and measuring method thereof |
| CN101520509B (en) * | 2009-02-13 | 2011-05-04 | 上海大学 | Method for comparatively measuring range of interframe of chaotic light time domain waveform |
| CN102176020A (en) * | 2010-12-30 | 2011-09-07 | 太原理工大学 | Chaos Laser ranging device based on liquid crystal |
| CN102176004A (en) * | 2011-02-22 | 2011-09-07 | 南京理工大学 | Laser time-of-flight measurement device based on multi-channel time delay estimation and method thereof |
| CN102506917A (en) * | 2011-12-03 | 2012-06-20 | 太原理工大学 | Optical fiber sensing device for optical fiber chaos laser device and method thereof |
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| CN106249249A (en) * | 2015-06-11 | 2016-12-21 | 东芝泰格有限公司 | Distance-measuring device |
| CN108254062A (en) * | 2018-01-05 | 2018-07-06 | 太原理工大学 | A kind of phase sensitive optical time domain reflection vibration detection device based on chaotic modulation |
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| CN113534178A (en) * | 2021-07-13 | 2021-10-22 | 西南大学 | Rapid correlation calculation method for ultra-wideband optical chaotic ranging |
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| US8502964B2 (en) | 2008-01-31 | 2013-08-06 | Taiyuan University Of Technology | Chaotic optical time domain reflectometer method and apparatus |
| WO2009097736A1 (en) * | 2008-01-31 | 2009-08-13 | Taiyuan University Of Technology | Chaotic optical time domain reflectometer and measuring method thereof |
| CN101520509B (en) * | 2009-02-13 | 2011-05-04 | 上海大学 | Method for comparatively measuring range of interframe of chaotic light time domain waveform |
| CN102176020A (en) * | 2010-12-30 | 2011-09-07 | 太原理工大学 | Chaos Laser ranging device based on liquid crystal |
| CN102176004A (en) * | 2011-02-22 | 2011-09-07 | 南京理工大学 | Laser time-of-flight measurement device based on multi-channel time delay estimation and method thereof |
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| CN102506917A (en) * | 2011-12-03 | 2012-06-20 | 太原理工大学 | Optical fiber sensing device for optical fiber chaos laser device and method thereof |
| CN102842845B (en) * | 2012-09-11 | 2014-02-05 | 哈尔滨工程大学 | Chaotic laser controller |
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| CN103424344B (en) * | 2013-08-25 | 2015-05-06 | 浙江大学 | Method and device for detecting nano particle sizes based on dual-wavelength optical fiber interference method |
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| CN104749579A (en) * | 2015-04-02 | 2015-07-01 | 太原理工大学 | Channel depth measuring method based on chaotic laser device and correlative method thereof |
| CN106249249A (en) * | 2015-06-11 | 2016-12-21 | 东芝泰格有限公司 | Distance-measuring device |
| CN106249249B (en) * | 2015-06-11 | 2018-11-09 | 东芝泰格有限公司 | Distance-measuring device |
| CN108254062A (en) * | 2018-01-05 | 2018-07-06 | 太原理工大学 | A kind of phase sensitive optical time domain reflection vibration detection device based on chaotic modulation |
| CN111699411A (en) * | 2018-01-31 | 2020-09-22 | 罗伯特·博世有限公司 | Lidar time-of-flight and intensity detection signal path based on phase-encoded multi-pulse transmission and single-bit oversampling matched filter detection |
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| CN115396027A (en) * | 2022-10-31 | 2022-11-25 | 长春理工大学 | Inter-aircraft distance measurement and communication integrated device and method |
| CN115396027B (en) * | 2022-10-31 | 2023-04-11 | 长春理工大学 | Inter-aircraft distance measurement and communication integrated device and method |
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Assignee: SHANXI CHANG CHENG MICROLIGHT EQUIPMENT CO., LTD. Assignor: Taiyuan University of Technology Contract fulfillment period: 2008.2.8 to 2013.2.7 contract change Contract record no.: 2009990001183 Denomination of invention: Apparatus and method for distance measurement using chaos laser of optical fiber laser device Granted publication date: 20080116 License type: Exclusive license Record date: 20091023 |
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